cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum-inspired Complex Convolutional Neural Networks
Creators: name: Shi, Shangshang
name: Wang, Zhimin
name: Cui, Guolong
name: Wang, Shengbin
name: Shang, Ruimin
name: Li, Wendong
name: Wei, Zhiqiang
name: Gu, Yongjian
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum-inspired neural network is one of the interesting researches at the junction of the two fields of quantum computing and deep learning. Several models of quantum-inspired neurons with real parameters have been proposed, which are mainly used for three-layer feedforward neural networks. In this work, we improve the quantum-inspired neurons by exploiting the complex-valued weights which have richer representational capacity and better non-linearity. We then extend the method of implementing the quantum-inspired neurons to the convolutional operations, and naturally draw the models of quantum-inspired convolutional neural networks (QICNNs) capable of processing high-dimensional data. Five specific structures of QICNNs are discussed which are different in the way of implementing the convolutional and fully connected layers. The performance of classification accuracy of the five QICNNs are tested on the MNIST and CIFAR-10 datasets. The results show that the QICNNs can perform better in classification accuracy on MNIST dataset than the classical CNN. More learning tasks that our QICNN can outperform the classical counterparts will be found.
description: 12pages, 6 figures
Turismo Rural – Perspetivas e Desafios
Creators: name: Kastenholz, Elisabeth
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2013

description: Este artigo reflete sobre a situação atual do turismo rural, sobretudo em Portugal, mas com referência também ao fenómeno e à sua investigação numa escala internacional. Após uma breve conceitualização deste tipo de turismo e enquadramento ao nível das transformações do mundo rural, analisamos mais detalhadamente o perfil e a possível evolução do mercado, oportunidades aparentes e constrangimentos a ultrapassar para permitir a realização de um turismo em meio rural, benéfica para todos os envolvidos e com potencial para contribuir para um desenvolvimento sustentável dos respetivos territórios rurais. A pesquisa sobre esta temática tem contribuído significativamente para uma melhor compreensão do fenómeno e dinâmicas do turismo rural bem como para o desenvolvimento de estratégias que visem tanto o maior sucesso de mercado como a sustentabilidade de negócios e destinos rurais.
description: Revista Turismo & Desenvolvimento, n.º 20 (2013)
Low Temperature Nanoscale Electronic Transport on the MoS_2 surface
Creators: name: Thamankar, R.
name: Yap, T. L.
name: Goh, K. E. J.
name: Troadec, C.
name: Joachim, C.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Two-probe electronic transport measurements on a Molybdenum Disulphide (MoS_2) surface were performed at low temperature (30K) under ultra-high vacuum conditions. Two scanning tunneling microscope tips were precisely positioned in tunneling contact to measure the surface current-voltage characteristics. The separation between the tips is controllably varied and measured using a high resolution scanning electron microscope. The MoS_2 surface shows a surface electronic gap (E_S) of 1.4eV measured at a probe separation of 50nm. Furthermore, the two- probe resistance measured outside the electronic gap shows 2D-like behavior with the two-probe separation.
description: 16 pages, 3 figures
Drazin-Inverse and heat capacity for driven random walks on the ring
Creators: name: Khodabandehlou, Faezeh
name: Maes, Irene
Publisher: name: arXiv
Year: 2022
Subjects: subject: Probability (math.PR)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We apply single and double tree-like representations of Markov jump processes on $\mathbb{Z}_N$ for obtaining their nonequilibrium heat capacity and for taking the diffusion limit $N\uparrow \infty$. The main tool is a graphical representation of the Drazin-inverse of the backward generator. In that way, the combination of algebraic and graph-theoretical approaches enables an exact computation of an important nonequilibrium quantity (excess heat) for Markov jump processes.
Toward a numerical deshaker for PFS
Creators: name: Schmidt, F.
name: Shatalina, I.
name: Kowalski, M.
name: Gac, N.
name: Saggin, B.
name: Giuranna, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The Planetary Fourier Spectrometer (PFS) onboard Mars Express (MEx) is the instrument with the highest spectral resolution observing Mars from orbit since January 2004. It permits studying the atmospheric structure, major and minor compounds. The present time version of the calibration is limited by the effects of mechanical vibration, currently not corrected. We proposed here a new approach to correct for the vibrations based on semi-blind deconvolution of the measurements. This new approach shows that a correction can be done efficiently with 85% reduction of the artefacts, in a equivalent manner to the stacking of 10 spectra. Our strategy is not fully automatic due to the dependence on some regularisation parameters. It may be applied on the complete PFS dataset, correcting the large-scale perturbation due to microvibrations for each spectrum independently. This approach is validated on actual PFS data of Short Wavelength Channel (SWC), perturbed by microvibrations. A coherence check can be performed and also validate our approach. Unfortunately, the coherence check can be done only on the first 310 orbits of MEx only, until the laser line has been switch off. More generally, this work may apply to numerically "deshake" Fourier Transform Spectrometer (FTS), widely used in space experiments or in the laboratory.
description: 18 pages, 8 figures, submitted to Planetary and Space Science
O Turismo internacional chinês e Portugal
Creators: name: Queirós, António Dos Santos
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2013

description: O emergir da China como o principal destino turístico mundial, mas também a sua liderança enquanto país emissor, são inseparáveis do crescimento da sua classe média e da mudança na motivação e gosto das viagens turísticas. Este artigo fornece informação estatística sobre os destinos mais procurados pelos turistas chineses e analisa o seu perfil, considerando que são sobretudo consumidores do turismo cultural. Apresenta, ainda, uma análise sobre as principais disfunções da oferta turística em Portugal face às características da procura que identifica os novos turistas chineses e propõe uma estratégia ibérica que supere essas disfunções e consiga promover o intercâmbio turístico com a China.
description: Revista Turismo & Desenvolvimento, n.º 20 (2013)
Kirche der Reformation unter dem südlichen Kreuz — Die Evangelische Kirche Lutherischen Bekenntnisses in Brasilien
Creators: name: Weingärtner, Lindolfo
Publisher: name: Lutherische Kirche in der Welt
Year: 1970

description: Lutherische Kirche in der Welt, Bd. 11 (1963): Jahrbuch des Martin-Luther-Bundes, Band 11
On the maximum energy of shock-accelerated cosmic rays at ultra-relativistic shocks
Creators: name: Reville, B.
name: Bell, A. R.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The maximum energy to which cosmic rays can be accelerated at weakly-magnetised ultra-relativistic shocks is investigated. We demonstrate that for such shocks, in which the scattering of energetic particles is mediated exclusively by ion skin-depth scale structures, as might be expected for a Weibel-mediated shock, there is an intrinsic limit on the maximum energy to which particles can be accelerated. This maximum energy is determined from the requirement that particles must be isotropised in the downstream plasma frame before the mean field transports them far downstream, and falls considerably short of what is required to produce ultra-high-energy cosmic rays. To circumvent this limit, a highly disorganised field is required on larger scales. The growth of cosmic-ray induced instabilities on wavelengths much longer than the ion-plasma skin depth, both upstream and downstream of the shock, is considered. While these instabilities may play an important role in magnetic field amplification at relativistic shocks, on scales comparable to the gyroradius of the most energetic particles, the calculated growth-rates have insufficient time to modify the scattering. Since strong modification is a necessary condition for particles in the downstream region to re-cross the shock, in the absence of an alternative scattering mechanism, these results imply that acceleration to higher energies is ruled out. If weakly-magnetised ultra-relativistic shocks are disfavoured as high energy particle accelerators in general, the search for potential sources of ultra-high-energy cosmic rays can be narrowed.
description: Revised version, highlighting references to previous work
Spatial regionalization based on optimal information compression
Creators: name: Kirkley, Alec
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Regionalization, spatially contiguous clustering, provides a means to reduce the effect of noise in sampled data and identify homogeneous areas for policy development among many other applications. Existing regionalization methods require user input such as the number of regions or a similarity measure between regions, which does not allow for the extraction of the natural regions defined solely by the data itself. Here we view the problem of regionalization as one of data compression and develop an efficient, parameter-free regionalization algorithm based on the minimum description length principle. We demonstrate that our method is capable of recovering planted spatial clusters in noisy synthetic data, and that it can meaningfully coarse-grain real demographic data. Using our description length formulation, we find that spatial ethnoracial data in U.S. metropolitan areas has become less compressible over the period from 1980 to 2010, reflecting the rising complexity of urban segregation patterns in these metros.
Turismo, Cultura e Regeneração Urbana. O renascimento das pequenas e médias cidades
Creators: name: Ferreira, Ana Maria
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2013

description: Pearce no seu artigo de 2001 afirmava que uma das linhas de investigação mais bem-sucedida na área do turismo urbano se relacionava o papel do turismo e da cultura na regeneração das cidades. Recentemente, Ashworth e Page (2011), no seguimento da análise desta temática, davam grande relevo ao “crescimento dos bairros culturais” (p.3). Dado que os bairros culturais são instrumentos de política urbana para o incremento da produção cultural e criativa e para o desenvolvimento do turismo e que se mantêm um tema de grande interesse a nível académico, decidiu-se enfocar este artigo no seu surgimento, desenvolvimento e evolução atual. Demonstra-se, através dos estudos de caso mencionados, que o sucesso destas políticas urbanas não é privilégio das cidades mundo, como defendem alguns investigadores. O que acontece é que a investigação teórica, incluindo a realizada na área do turismo urbano, tem sido dominada pelos estudos dedicados às grandes cidades e às cidades globais, esquecendo as pequenas e médias.
description: Revista Turismo & Desenvolvimento, n.º 20 (2013)
Concatenated Coding Using Linear Schemes for Gaussian Broadcast Channels with Noisy Channel Output Feedback
Creators: name: Ahmad, Ziad
name: Chance, Zachary
name: Love, David J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Linear coding schemes have been the main choice of coding for the additive white Gaussian noise broadcast channel (AWGN-BC) with noiseless feedback in the literature. The achievable rate regions of these schemes go well beyond the capacity region of the AWGN-BC without feedback. In this paper, a concatenating coding design for the $K$-user AWGN-BC with noisy feedback is proposed that relies on linear feedback schemes to achieve rate tuples outside the no-feedback capacity region. Specifically, a linear feedback code for the AWGN-BC with noisy feedback is used as an inner code that creates an effective single-user channel from the transmitter to each of the receivers, and then open-loop coding is used for coding over these single-user channels. An achievable rate region of linear feedback schemes for noiseless feedback is shown to be achievable by the concatenated coding scheme for sufficiently small feedback noise level. Then, a linear feedback coding scheme for the $K$-user symmetric AWGN-BC with noisy feedback is presented and optimized for use in the concatenated coding scheme. Lastly, we apply the concatenated coding design to the two-user AWGN-BC with a single noisy feedback link from one of the receivers.
description: submitted to IEEE Transactions on Information Theory
Electrical Conductances and association constants in dilute aqueous NdCl\textsubscript{3} solutions from 298 to 523 K along an isobar of 25 MPa
Creators: name: Yoon, Tae Jun
name: Craddok, Erica P.
name: Maerzke, Katie A.
name: Currier, Robert P.
name: Findikoglu, Alp T.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Electrical measurements were performed in dilute aqueous NdCl3 solutions from 298 to 523 K along the 25 MPa isobar to obtain limiting conductances and association constants. The specific conductance data were estimated using a continuous flow cell and a Markov Chain Monte Carlo (MCMC) correction algorithm. The limiting conductances for the salts in water were derived by regressing the mean spherical approximation (MSA) conductance model and speciation analyses based on the MCMC algorithm and the Deep Earth Water (DEW) model. The limiting conductances derived from the experimental data agree well with a predictive correlation proposed by Smolyakov, Anderko, and Lencka. Only the first association constant between neodymium and chloride could be derived at low temperatures (< 373 K) due to the apparent large statistical uncertainty of the second association constant. Above 373 K, both association constants could be derived and show a reasonable agreement with Migdisov and Williams-Jones and Gammons et al.
description: 34 pages, 8 figures, to be submitted as an article
Investigação em Turismo: A experiência da Revista Turismo & Desenvolvimento
Creators: name: Costa, Carlos
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2013

description: Investigação rigorosa, generalizável e preferencialmente feita em parceria com as empresas e organizações do turismo, constitui um vetor estratégico para a criação de um sector, e de produtores do conhecimento, mais fortes, articulados e com sentido de responsabilidade social. Este artigo revisita alguns daqueles que se constituem como sendo elementos críticos da investigação em turismo, e discute a desarticulação, e afastamento, entre produtores e consumidores de conhecimento. Tendo par base 10 anos de publicação da RT&D, apresentam-se indicadores sobre o contributo dado pela Revista Turismo & Desenvolvimento à academia e ao sector empresarial do turismo.
description: Revista Turismo & Desenvolvimento, n.º 20 (2013)
Compression of a confined semiflexible polymer under direct and oscillating fields
Creators: name: Radhakrishnan, Keerthi
name: Singh, Sunil P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The folding transition of biopolymers from the coil to compact structures has attracted wide research interest in the past and is well studied in polymer physics. Recent seminal works on DNA in confined devices have shown that these long biopolymers tend to collapse under an external field, contrary to the previously reported stretching. These long folded structures have a tendency to form knots that has profound implications in gene regulation and various other biological functions. These knots have been mechanically induced via optical tweezers, nanochannel confinement, etc., until recently, where uniform field driven compression lead to self entanglement of DNA. In this work, we capture the compression of a confined semiflexible polymer under direct and oscillating fields, using a coarse-grained computer simulation model in the presence of long-range hydrodynamics. Within this framework, we show that subjected to direct field, chains in stronger confinements exhibit substantial compaction, contrary to the one in moderate confinements or bulk, where such compaction is absent. Interestingly, an alternating field within an optimum frequency can effectuate this compression even in moderate or no confinement. Additionally, we show that the bending rigidity has a profound influence on the chains folding favourability under direct and alternating fields. This field induced collapse is a quintessential hydrodynamic phenomenon, resulting in intertwined knotted structures, even for shorter chains, unlike DNA knotting experiments, where it happens exclusively for longer chains.
Quantum chaos in 2D gravity
Creators: name: Altland, Alexander
name: Post, Boris
name: Sonner, Julian
name: van der Heijden, Jeremy
name: Verlinde, Erik
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We present a quantitative and fully non-perturbative description of the ergodic phase of quantum chaos in the setting of two-dimensional gravity. To this end we describe the doubly non-perturbative completion of semiclassical 2D gravity in terms of its associated universe field theory. The guiding principle of our analysis is a flavor-matrix theory (fMT) description of the ergodic phase of holographic gravity, which exhibits $\mathrm{U}(n|n)$ causal symmetry breaking and restoration. JT gravity and its 2D-gravity cousins alone do not realize an action principle with causal symmetry, however we demonstrate that their {\it universe field theory}, the Kodaira-Spencer (KS) theory of gravity, does. After directly deriving the fMT from brane-antibrane correlators in KS theory, we show that causal symmetry breaking and restoration can be understood geometrically in terms of different (topological) D-brane vacua. We interpret our results in terms of an open-closed string duality between holomorphic Chern-Simons theory and its closed-string equivalent, the KS theory of gravity. Emphasis will be put on relating these geometric principles to the characteristic spectral correlations of the quantum ergodic phase.
description: 49 pages, 2 appendices, 9 figures; v3: rewrote introduction, simplified Fig. 1
Tourism and Regional Growth: A Panel Data Approach
Creators: name: Vaz, Margarida
name: Manso, José
name: Silva, Jorge
name: Baltazar, Emília
name: Reis, Tiago
Publisher: name: Journal of Tourism & Development
Year: 2012

description: Given the relevance of tourism to the Portuguese regional economies, the main aim of this paper is to study whether the investments made in related-tourism facilities contributed to the regional growth of all the Portuguese regions included in the NUTS II Norte and Alentejo, with special emphasis on the NUTS III Alto-Trás-os-Montes and Alentejo Central. These two regions have different usage patterns of the infrastructure and different levels of tourism development. A panel data approach was used to assess the contribution of several related tourism variables to the growth of GDP per capita of those regions.
description: Journal of Tourism & Development, vol. 3 n.º 17/18 (2012)
Cluster Functional Renormalization Group
Creators: name: Reuther, Johannes
name: Thomale, Ronny
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Functional renormalization group (FRG) has become a diverse and powerful tool to derive effective low-energy scattering vertices of interacting many-body systems. Starting from a non-interacting expansion point of the action, the flow of the RG parameter Lambda allows to trace the evolution of the effective one-particle and two-particle vertices towards low energies by taking into account the vertex corrections between all parquet channels in an unbiased fashion. In this work, we generalize the expansion point at which the diagrammatic resummation procedure is initiated from a free UV limit to a cluster product state. We formulate a cluster FRG scheme where the non-interacting building blocks (i.e., decoupled spin clusters) are treated exactly, and the inter-cluster couplings are addressed via RG. As a benchmark study, we apply our cluster FRG scheme to the spin-1/2 bilayer Heisenberg model (BHM) on a square lattice where the neighboring sites in the two layers form the individual 2-site clusters. Comparing with existing numerical evidence for the BHM, we obtain reasonable findings for the spin susceptibility, magnon dispersion, and magnon quasiparticle weight even in coupling regimes close to antiferromagnetic order. The concept of cluster FRG promises applications to a large class of interacting electron systems.
description: 17 pages, 13 figures
Noise-Tolerant Object Detection and Ranging Using Quantum Correlations
Creators: name: Kuniyil, Hashir
name: Ozel, Helin
name: Yılmaz, Hasan
name: Durak, Kadir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Imaging, detection and ranging of objects in the presence of significant background noise is a fundamental challenge in optical sensing. Overcoming the limitations imposed in conventional methods, quantum light sources show higher resistance against noise in a time-correlation-based quantum illumination. Here, we introduce the advantage of using not only time correlations but also polarization correlations in photon pairs in the detection of an object that is embedded in a noisy background. In this direction, a time- and polarization-correlated photon pair source using the spontaneous parametric down-conversion process is exploited. We found that the joint measurement of correlated pairs allows distinguishing the signal from the noise photons and that leads to an improved signal-to-noise ratio. Our comparative study revealed that using polarization correlations in addition to time correlations provides improved noise rejection. Furthermore, we show that polarization correlation allows undoing the detector limitation where high background often leads to detector saturation.
description: The file is 7 pages of double columns data and contains 6 figures
Force-free field modeling of twist and braiding-induced magnetic energy in an active-region corona
Creators: name: Thalmann, J. K.
name: Tiwari, S. K.
name: Wiegelmann, T.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The theoretical concept that braided magnetic field lines in the solar corona may dissipate a sufficient amount of energy to account for the brightening observed in the active-region corona, has been substantiated by high-resolution observations only recently. From the analysis of coronal images obtained with the High Resolution Coronal Imager, first observational evidence of the braiding of magnetic field lines was reported by Cirtain et al. 2013 (hereafter CG13). We present nonlinear force-free reconstructions of the associated coronal magnetic field based on vector SDO/HMI magnetograms. We deliver estimates of the free magnetic energy associated to a braided coronal structure. Our model results suggest (~100 times) more free energy at the braiding site than analytically estimated by CG13, strengthening the possibility of the active-region corona being heated by field line braiding. We were able to assess the coronal free energy appropriately by using vector field measurements and attribute the lower energy estimate of CG13 to the underestimated (by a factor of 10) azimuthal field strength. We also quantify the increase of the overall twist of a flare-related flux rope which had been claimed by CG13. From our models we find that the overall twist of the flux rope increased by about half a turn within twelve minutes. Unlike another method, to which we compare our results to, we evaluate the winding of the flux rope's constituent field lines around each other purely based on their modeled coronal 3D field line geometry -- to our knowledge for the first time.
description: Accepted for publication in ApJ (8 pages, 5 figures)
Constructing the space of quasisymmetric stellarators
Creators: name: Rodriguez, Eduardo
name: Sengupta, Wrick
name: Bhattacharjee, Amitava
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: A simplified view of the space of optimised stellarators has the potential to guide and aid the design efforts of magnetic confinement configurations suitable for future fusion reactors. We present one such view for the class of quasisymmetric stellarators based on their approximate description near their centre (magnetic axis). The result is a space that captures existing designs and presents new ones, providing a common framework to study them. Such a simplified construction offers a basic topological approach, guided by certain theoretical and physical choices, which this paper presents in detail.
Planorbidae
Creators: name: Cremonte, Florencia
name: Drago, Fabiana B.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Hygrophila
Planorbidae

description: Family Ancylidae   Gundlachia concentrica (d'Orbigny)
 Posthodiplostomum nanum Dubois, 1937
description: Published as part of Cremonte, Florencia & Drago, Fabiana B., 2007, Checklist of digenean parasites of birds from Argentina, pp. 1-36 in Zootaxa 1403 on page 28, DOI: 10.5281/zenodo.273687
Quantum Conductivity for Metal-Insulator-Metal Nanostructures
Creators: name: Haus, Joseph W.
name: de Ceglia, Domenico
name: Vincenti, Maria Antonietta
name: Scalora, Michael
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a methodology based on quantum mechanics for assigning quantum conductivity when an ac field is applied across a variable gap between two plasmonic nanoparticles with an insulator sandwiched between them. The quantum tunneling effect is portrayed by a set of quantum conductivity coefficients describing the linear ac conductivity responding at the frequency of the applied field and nonlinear coefficients that modulate the field amplitude at the fundamental frequency and its harmonics. The quantum conductivity, determined with no fit parameters, has both frequency and gap dependence that can be applied to determine the nonlinear quantum effects of strong applied electromagnetic fields even when the system is composed of dissimilar metal nanostructures. Our methodology compares well to results on quantum tunneling effects reported in the literature and it is simple to extend it to a number of systems with different metals and different insulators between them.
Generalized Fermat's principle and action for light rays in a curved spacetime
Creators: name: Frolov, Valeri P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We start with formulation of the generalized Fermat's principle for light propagation in a curved spacetime. We apply Pontryagin's minimum principle of the optimal control theory and obtain an effective Hamiltonian for null geodesics in a curved spacetime. We explicitly demonstrate that dynamical equations for this Hamiltonian correctly reproduce null geodesic equations. Other forms of the action for light rays in a curved spacetime are also discussed.
description: 7 pages 1 figure
Ich habe zwar seiner Zeit keine Reaktion gesehen, aber nach meiner jetztigen Anschauungsweise, die gegen der frühere eine ganz andere ist, sehe ich eine furchbare Reaktion. Lachen Sie nur meine Herren, aber schauen Sie die Sache nach meiner Stellung an, so werden Sie die Reaction auch sehen.; [1848]
Creators: name: Stern, S.
Publisher: name: Universitätsbibliothek der Ludwig-Maximilians-Universität München
Year: 2018

description: No. XVI
Uma proposta metodológica de identificação e localização de clusters: aplicação empírica ao sector do turismo
Creators: name: Estevão, Cristina
name: Ferreira, João
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2012

description: O setor do turismo, sendo de extrema importância para a economia mundial, constitui igualmente, um motor de crescimento económico. Os clusters e a sua aplicação têm sido alvo de várias abordagens no estudo teórico e prático do desenvolvimento económico regional, durante a última década, em todo o mundo. A concentração geográfica deste tipo de atividades ocasiona, muitas vezes, um uso excessivo do termo cluster para designar essas mesmas concentrações regionais. Muitos têm sido os estudos de identificação de clusters em diversos contextos, porém baseados, fundamentalmente, em análises qualitativas e/ou quantitativas que tendem a negligenciar aspetos metodológicos fundamentais inerentes à identificação e operacionalização de clusters. O objetivo desta investigação visa contribuir para a redução dessa lacuna metodológica da investigação empírica, mediante a proposta e aplicação de uma metodologia quantitativa capaz de evidenciar, empiricamente e de forma robusta, a identificação e localização de clusters na indústria do turismo em Portugal. Com base na metodologia adotada foram identificados 555 clusters distribuídos por 10 atividades relacionados com o alojamento, a restauração e a animação.
description: Revista Turismo & Desenvolvimento, vol. 3 n.º 17/18 (2012)
Chilinidae
Creators: name: Cremonte, Florencia
name: Drago, Fabiana B.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Hygrophila
Chilinidae

description: Family Chilinidae   Chilina dombeiana (Bruiguiere)
 Catatropis chilinae Flores & Brugni, 2003
description: Published as part of Cremonte, Florencia & Drago, Fabiana B., 2007, Checklist of digenean parasites of birds from Argentina, pp. 1-36 in Zootaxa 1403 on page 28, DOI: 10.5281/zenodo.273687
Tourism as a long-run economic growth factor in Portugal: Evidence from causality analysis
Creators: name: Bento, João Paulo Cerdeira
name: Santos, Madalena
Publisher: name: Journal of Tourism & Development
Year: 2012

description: This paper investigates empirically the role of tourism in the Portuguese long-run economic output growth on quarterly data (1997:1 to 2010:4). The augmented Granger causality test approach developed by Toda and Yamamoto (1995) is employed to ascertain the direction of causality between variables in a bi-variate vector autoregressions (VAR) system using the Seemingly Unrelated Regression (SUR) method. The results provide evidence of a strong one-way directional causality between tourism and economic growth and the necessary argument to support the tourism led growth hypothesis. This result has important policy implications for where government investments should be targeted giving a further catalyst to economic growth.
description: Journal of Tourism & Development, vol. 3 n.º 17/18 (2012)
Active Noise Control with Sampled-Data Filtered-x Adaptive Algorithm
Creators: name: Nagahara, Masaaki
name: Hamaguchi, Ken-ichi
name: Yamamoto, Yutaka
Publisher: name: arXiv
Year: 2013
Subjects: subject: Information Theory (cs.IT)
subject: Systems and Control (eess.SY)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics

description: Analysis and design of filtered-x adaptive algorithms are conventionally done by assuming that the transfer function in the secondary path is a discrete-time system. However, in real systems such as active noise control, the secondary path is a continuous-time system. Therefore, such a system should be analyzed and designed as a hybrid system including discrete- and continuous- time systems and AD/DA devices. In this article, we propose a hybrid design taking account of continuous-time behavior of the secondary path via lifting (continuous-time polyphase decomposition) technique in sampled-data control theory.
Taxa sobre as dormidas: Uma alternativa para o financiamento do turismo sustentável em Cabo Verde1
Creators: name: Monteiro, João Evangelista Dias
Publisher: name: Revista Turismo & Desenvolvimento
Year: 2012

description: Alguns países têm utilizado impostos e taxas sobre a atividade turística no intuito de arrecadar recursos para financiar o seu processo de crescimento e o desenvolvimento. A literatura sobre a análise de benefícios e malefícios da taxação da atividade turística sobre o bem-estar das comunidades receptoras é composta por uma série de estudos com resultados bastante controversos. Nesta perspetiva, este artigo tem como objetivo justificar a importância da criação de uma taxa sobre as dormidas dos turistas internacionais, para o financiamento do crescimento e desenvolvimento do turismo sustentável na República de Cabo Verde. Do ponto de vista da gestão pública do turismo, a eficácia e a eficiência desta taxa estão associadas ao destino dos recursos arrecadados através dela. Sendo assim, esta taxa é justificável caso os recursos sejam utilizados no aumento da competitividade turística de Cabo Verde, por meio de investimentos em infraestrutura geral e capacitação profissional, além do estímulo a pequenos negócios no setor do turismo. Desta forma, os benefícios económicos e sociais substanciais superam o seu impacte irrelevante na competitividade de preços do país como destino turístico internacional.
description: Revista Turismo & Desenvolvimento, vol. 3 n.º 17/18 (2012)
Passport: Improving Automated Formal Verification Using Identifiers
Creators: name: Sanchez-Stern, Alex
name: First, Emily
name: Zhou, Timothy
name: Kaufman, Zhanna
name: Brun, Yuriy
name: Ringer, Talia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences

description: Formally verifying system properties is one of the most effective ways of improving system quality, but its high manual effort requirements often render it prohibitively expensive. Tools that automate formal verification, by learning from proof corpora to suggest proofs, have just begun to show their promise. These tools are effective because of the richness of the data the proof corpora contain. This richness comes from the stylistic conventions followed by communities of proof developers, together with the logical systems beneath proof assistants. However, this richness remains underexploited, with most work thus far focusing on architecture rather than making the most of the proof data. In this paper, we develop Passport, a fully-automated proof-synthesis tool that systematically explores how to most effectively exploit one aspect of that proof data: identifiers. Passport enriches a predictive Coq model with three new encoding mechanisms for identifiers: category vocabulary indexing, subword sequence modeling, and path elaboration. We compare Passport to three existing base tools which Passport can enhance: ASTactic, Tac, and Tok. In head-to-head comparisons, Passport automatically proves 29% more theorems than the best-performing of these base tools. Combining the three Passport-enhanced tools automatically proves 38% more theorems than the three base tools together, without Passport's enhancements. Finally, together, these base tools and Passport-enhanced tools prove 45% more theorems than the combined base tools without Passport's enhancements. Overall, our findings suggest that modeling identifiers can play a significant role in improving proof synthesis, leading to higher-quality software.
Cochliopidae
Creators: name: Cremonte, Florencia
name: Drago, Fabiana B.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Cochliopidae

description: Family Cochliopidae   Heleobia australis (d'Orbigny)
 Psilochasmus oxyurus (Creplin, 1825) Lühe, 1910 Heleobia australis australis (d'Orbigny)
 Maritrema bonaerensis Etchegoin & Martorelli, 1997 Heleobia castellanosae (Gaillard)
 Ascocotyle (Ascocotyle) secunda Ostrowski de Núñez, 2001
 Ascocotyle (Ascocotyle) tertia Ostrowski de Núñez, 2001
 Ascocotyle (Phagicola) angeloi Travassos, 1928
 Ascocotyle (Phagicola) diminuta (Stunkard & Haviland, 1924)
 Echinochasmus talaensis Martorelli, 1985
 Pygidiopsis australis Ostrowski de Núñez, 1996 Heleobia conexa (Gaillard).
 Levinseniella cruzi Travassos, 1920
 Microphallus simillimus (Travassos, 1920) Martorelli, 1991
 Microphallus szidati Martorelli, 1986
 Heleobia hatcheri Pilsbry
 Catatropis hatcheri Flores & Brugni, 2006 Heleobia parchappei (d’Orbigny)
 Ascocotyle (Ascocotyle) secunda Ostrowski de Núñez, 2001
 Ascocotyle (Ascocotyle) tertia Ostrowski de Núñez, 2001
 Ascocotyle (Leighia) hadra Ostrowski de Núñez, 1992
 Ascocotyle (Phagicola) diminuta (Stunkard & Haviland, 1924)
 Cyclocoelum (Cyclocoelum) microstomum (Creplin, 1829)
 Hyptiasmus brumpti Dollfus, 1948
 Levinseniella cruzi Travassos, 1920
 Microphallus szidati Martorelli, 1986
 Pygidiopsis crassus Ostrowski de Núñez, 1995 Heleobia piscium (d'Orbigny)
 Ascocotyle (Ascocotyle) tenuicollis Price, 1935
 Pygidiopsis sp.
description: Published as part of Cremonte, Florencia & Drago, Fabiana B., 2007, Checklist of digenean parasites of birds from Argentina, pp. 1-36 in Zootaxa 1403 on page 28, DOI: 10.5281/zenodo.273687
Regimes in astrophysical lensing: refractive optics, diffractive optics, and the Fresnel scale
Creators: name: Jow, Dylan L.
name: Pen, Ue-Li
name: Feldbrugge, Job
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Astrophysical lensing has typically been studied in two regimes: diffractive optics and refractive optics. Diffractive optics is characterized by a perturbative expansion of the Kirchhoff-Fresnel diffraction integral, while refractive optics is characterized by the stationary phase approximation. Previously, it has been assumed that the Fresnel scale, $R_F$ , is the relevant physical scale that separates these two regimes. With the recent introduction of Picard-Lefschetz theory to the field of lensing, it has become possible to generalize the refractive description of discrete images to all wave parameters, and, in particular, exactly evaluate the diffraction integral at all frequencies. In this work, we assess the regimes of validity of refractive and diffractive approximations for a simple one-dimensional lens model through comparison with this exact evaluation. We find that, contrary to previous assumptions, the true separation scale between these regimes is given by $R_F / \sqrtκ$, where $κ$ is the convergence of the lens. Thus, when the lens is strong, refractive optics can hold for arbitrarily small scales. We also argue that intensity variations in diffractive optics are generically small, which has implications for the study of strong diffractive scintillation (DISS).
description: 15 pages, 8 figures
Collisionless microinstabilities in stellarators I - analytical theory of trapped-particle modes
Creators: name: Helander, P.
name: Proll, J. H. E.
name: Plunk, G. G.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: This is the first of two papers about collisionless, electrostatic micro-instabilities in stellarators, with an emphasis on trapped-particle modes. It is found that, in so-called maximum-$J$ configurations, trapped-particle instabilities are absent in large regions of parameter space. Quasi-isodynamic stellarators have this property (approximately), and the theory predicts that trapped electrons are stabilizing to all eigenmodes with frequencies below the electron bounce frequency. The physical reason is that the bounce-averaged curvature is favorable for all orbits, and that trapped electrons precess in the direction opposite to that in which drift waves propagate, thus precluding wave-particle resonance. These considerations only depend on the electrostatic energy balance, and are independent of all geometric properties of the magnetic field other than the maximum-$J$ condition. However, if the aspect ratio is large and the instability phase velocity differs greatly from the electron and ion thermal speeds, it is possible to derive a variational form for the frequency showing that stability prevails in a yet larger part of parameter space than what follows from the energy argument. Collisionless trapped-electron modes should therefore be more stable in quasi-isodynamic stellarators than in tokamaks.
description: 9 pages, 1 figure
Towards Domain-Independent and Real-Time Gesture Recognition Using mmWave Signal
Creators: name: Li, Yadong
name: Zhang, Dongheng
name: Chen, Jinbo
name: Wan, Jinwei
name: Zhang, Dong
name: Hu, Yang
name: Sun, Qibin
name: Chen, Yan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Human gesture recognition using millimeter-wave (mmWave) signals provides attractive applications including smart home and in-car interfaces. While existing works achieve promising performance under controlled settings, practical applications are still limited due to the need of intensive data collection, extra training efforts when adapting to new domains, and poor performance for real-time recognition. In this paper, we propose DI-Gesture, a domain-independent and real-time mmWave gesture recognition system. Specifically, we first derive signal variations corresponding to human gestures with spatial-temporal processing. To enhance the robustness of the system and reduce data collecting efforts, we design a data augmentation framework for mmWave signals based on correlations between signal patterns and gesture variations. Furthermore, a spatial-temporal gesture segmentation algorithm is employed for real-time recognition. Extensive experimental results show DI-Gesture achieves an average accuracy of 97.92\%, 99.18\%, and 98.76\% for new users, environments, and locations, respectively. We also evaluate DI-Gesture in challenging scenarios like real-time recognition and sensing at extreme angles, all of which demonstrate the superior robustness and effectiveness of our system.
description: This paper has been accepted by IEEE Transactions on Mobile Computing (2022)
Physidae
Creators: name: Cremonte, Florencia
name: Drago, Fabiana B.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Hygrophila
Physidae

description: Family Physidae   Stenophysa marmorata (Martens)
 Echinostoma parcespinosum Lutz, 1924
description: Published as part of Cremonte, Florencia & Drago, Fabiana B., 2007, Checklist of digenean parasites of birds from Argentina, pp. 1-36 in Zootaxa 1403 on page 28, DOI: 10.5281/zenodo.273687
Lorentz Transformation of Blackbody Radiation
Creators: name: Ford, G. W.
name: O'Connell, R. F.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We present a simple calculation of the Lorentz transformation of the spectral distribution of blackbody radiation at temperature T. Here we emphasize that T is the temperature in the blackbody rest frame and does not change. We thus avoid the confused and confusing question of how temperature transforms. We show by explicit calculation that at zero temperature the spectral distribution is invariant. At finite temperature we find the well known result familiar in discussions of the the 2.7! K cosmic radiation.
description: 6 pages
Hyriidae
Creators: name: Cremonte, Florencia
name: Drago, Fabiana B.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Bivalvia
Unionoida
Hyriidae

description: Family Hyriidae   Diplodon chilensis (Gray)
 Echinoparyphium megacirrus Semenas, Brugni & Ostrowski de Núñez, 1999
description: Published as part of Cremonte, Florencia & Drago, Fabiana B., 2007, Checklist of digenean parasites of birds from Argentina, pp. 1-36 in Zootaxa 1403 on page 29, DOI: 10.5281/zenodo.273687
Connecting Infrared Surface Brightness Fluctuation Distances to Type Ia Supernova Hosts: Testing the Top Rung of the Distance Ladder
Creators: name: Garnavich, Peter
name: Wood, Charlotte M.
name: Milne, Peter
name: Jensen, Joseph B.
name: Blakeslee, John P.
name: Brown, Peter J.
name: Scolnic, Daniel
name: Rose, Benjamin
name: Brout, Dillon
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We compare infrared surface brightness fluctuation (IR SBF) distances measured in galaxies that have hosted type Ia supernovae (SNIa) to distances estimated from SNIa light curve fits. We show that the properties of SNIa found in IR SBF hosts are very different from those exploding in Cepheid calibrators, therefore, this is a direct test of systematic uncertainties on estimation of the Hubble constant (Ho) using supernovae. The IR SBF results from Jensen et al. (2021; arXiv:2105.08299) provide a large and uniformly measured sample of IR SBF distances which we directly compare with distances to 25 SNIa host galaxies. We divide the Hubble flow SNIa into sub-samples that best match the divergent supernova properties seen in the IR SBF hosts and Cepheid hosts. We further divide the SNIa into a sample with light curve widths and host masses that are congruent to those found in the SBF-calibrated hosts. We refit the light curve stretch and color correlations with luminosity, and use these revised parameters to calibrate the Hubble flow supernovae with IR SBF calibrators. Relative to the Hubble flow, the average calibrator distance moduli vary by 0.03mag depending on the SNIa subsamples examined and this adds a 1.8% systematic uncertainty to our Hubble constant estimate. Based on the IR SBF calibrators, Ho=74.6$\pm$0.9(stat)$\pm$ 2.7(syst) km/s/Mpc, which is consistent with the Hubble constant derived from supernovae calibrated from Cepheid variables. We conclude that IR SBF provides reliable calibration of SNIa with a precision comparable to Cepheid calibrators, and with a significant saving in telescope time.
description: 18 pages, 10 figures, 4 tables, accepted for publication in the Astrophysical Journal