arXiv subjects

D. J. Wang

Publications and source records attributed to D. J. Wang.

11 recordsLinked to original sources

arXiv2025

ManchuTTS: Towards High-Quality Manchu Speech Synthesis via Flow Matching and Hierarchical Text Representation

As an endangered language, Manchu presents unique challenges for speech synthesis, including severe data scarcity and strong phonological agglutination. This paper proposes ManchuTTS(Manchu Text to Speech), a novel approach tailored to Manchu's linguistic characteristics. To handle agglutination, this method designs a three-tier text representation (phoneme, syllable, prosodic) and a cross-modal hierarchical attention mechanism for multi-granular alignment. The synthesis model integrates deep convolutional networks with a flow-matching Transformer, enabling efficient, non-autoregressive generation. This method further introduce a hierarchical contrastive loss to guide structured acoustic-linguistic correspondence. To address low-resource constraints, This method construct the first Manchu TTS dataset and employ a data augmentation strategy. Experiments demonstrate that ManchuTTS attains a MOS of 4.52 using a 5.2-hour training subset derived from our full 6.24-hour annotated corpus, outperforming all baseline models by a notable margin. Ablations confirm hierarchical guidance improves agglutinative word pronunciation accuracy (AWPA) by 31% and prosodic naturalness by 27%.

cs.CL↗

arXiv2017

Quantitative Entropy Study of Language Complexity

We study the entropy of Chinese and English texts, based on characters in case of Chinese texts and based on words for both languages. Significant differences are found between the languages and between different personal styles of debating partners. The entropy analysis points in the direction of lower entropy, that is of higher complexity. Such a text analysis would be applied for individuals of different styles, a single individual at different age, as well as different groups of the population.

cs.CL↗

arXiv2016

$Λ$ polarization in peripheral collisions at moderate relativistic energies

The polarization of $Λ$ hyperons from relativistic flow vorticity is studied in peripheral heavy ion reactions at FAIR and NICA energies, just above the threshold of the transition to the Quark-Gluon Plasma. Previous calculations at higher energies with larger initial angular momentum, predicted significant $Λ$ polarization based on the classical vorticity term in the polarization, while relativistic modifications decreased the polarization and changed its structure in the momentum space. At the lower energies studied here, we see the same effect namely that the relativistic modifications decrease the polarization arising from the initial shear flow vorticity.

nucl-th↗

arXiv2015

Two particle correlation effects and Differential HBT for rotation in heavy ion collisions

Peripheral heavy ion reactions at ultra relativistic energies have large angular momentum that can be studied via two particle correlations using the Differential Hanbury Brown and Twiss method. We analyze the possibilities and sensitivity of the method in a rotating system. We also study an expanding solution of the fluid dynamical model of heavy ion reactions.

nucl-th↗

arXiv2014

Rotation in an exact hydro model

We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

hep-ph↗

arXiv2014

Differential HBT Applied to Relativistic Fluid Dynamics

The earlier introduced Differential HBT method aiming for detecting rotation is used to analyze the fluid dynamical model results of ultra-relativistic heavy ion reactions where the initial state has substantial angular momentum. The rotation effect and Kelvin Helmholtz Instability, lead to space-time momentum correlations, which can be detected by the method.

nucl-th↗

arXiv2013

Lambda Polarization in Peripheral Heavy Ion Collisions

We predict the polarization of Lambda and antiLambda hyperons in peripheral heavy ion collisions at ultrarelativistic energy, based on the assumption of local thermodynamical equilibrium at freeze-out. The polarization vector is proportional to the curl of the inverse temperature four-vector field and its length, of the order of percents, is maximal for particle with moderately high momentum lying on the reaction plane. A selective measurement of these particles could make Lambda polarization detectable.

nucl-th↗

arXiv2013

Flow Vorticity in Peripheral High Energy Heavy Ion Collisions

The vorticity development is studied in the reaction plane of peripheral relativistic heavy ion reactions where the initial state has substantial angular momentum. The earlier predicted rotation effect and Kelvin Helmholtz Instability, lead to significant initial vorticity and circulation. In low viscosity QGP this vorticity remains still significant at the time of freeze out of the system, even if damping due to the explosive expansion and the dissipation decreases the vorticity and circulation. In the reaction plane the vorticity arises from the initial angular momentum, and it is stronger than in the transverse plane where vorticity is caused by random fluctuations only.

nucl-th↗

arXiv2013

Viscous potential flow analysis of peripheral heavy ion collisions

The conditions for the development of a Kelvin-Helmholtz Instability (KHI) for the Quark-gluon Plasma (QGP) flow in a peripheral heavy-ion collision is investigated. The projectile and target side particles are separated by an energetically motivated hypothetical surface, characterized with a phenomenological surface tension. In such a view, a classical potential flow approximation is considered and the onset of the KHI is studied. The growth rate of the instability is computed as function of phenomenological parameters characteristic for the QGP fluid: viscosity, surface tension and flow layer thickness.

nucl-th↗

arXiv2012

QGP flow fluctuations and the characteristics of higher moments

The dynamical development of expanding Quark-gluon Plasma (QGP) flow is studied in a 3+1D fluid dynamical model with a globally symmetric, initial condition. We minimize fluctuations arising from complex dynamical processes at finite impact parameters and from fluctuating random initial conditions to have a conservative fluid dynamical background estimate for the statistical distributions of the thermodynamical parameters. We also avoid a phase transition in the equation of state, and we let the matter supercool during the expansion. Then central Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV are studied in an almost perfect fluid dynamical model, with azimuthally symmetric initial state generated in a dynamical flux-tube model. The general development of thermodynamical extensives are also shown for lower energies. We observe considerable deviations from a thermal equilibrium source as a consequence of the fluid dynamical expansion arising from a least fluctuating initial state.

nucl-th↗

arXiv2012

Quantum spin mixing in a binary mixture of spin-1 atomic condensates

We study quantum spin mixing in a binary mixture of spin-1 condensates including coherent interspecies mixing process, using the familiar spinor condensates of $^{87}$Rb and $^{23}$Na atoms in the ground lower hyperfine F=1 manifolds as prototype examples. Within the single spatial mode approximation for each of the two spinor condensates, the mixing dynamics reduce to that of three coupled nonlinear pendulums with clear physical interpretations. Using suitably prepared initial states, it is possible to determine the interspecies singlet-pairing as well as spin-exchange interactions from the subsequent mixing dynamics.

cond-mat.quant-gas↗