1,603 research outputs found
Quark number scaling of hadronic spectra and constituent quark degree of freedom in -Pb collisions at TeV
We show that the experimental data of spectra of identified hadrons
released recently by ALICE collaboration for -Pb collisions at
TeV exhibit a distinct universal behavior --- the quark
number scaling. We further show that the scaling is a direct consequence of
quark (re-)combination mechanism of hadronization and can be regarded as a
strong indication of the existence of the underlying source with constituent
quark degree of freedom for the production of hadrons in -Pb collisions at
such high energies. We make also predictions for production of other hadrons.Comment: 5 pages, 3 figure
Effects of Marangoni numbers on thermocapillary drop migration: constant for quasi-steady state?
The overall {\it steady}-state energy balance with two phases in a flow
domain requires that the change in energy of the domain is equal to the
difference between the total energy entering the domain and that leaving the
domain. From the condition, the integral thermal flux across the surface is
studied for a {\it steady} thermocapillary drop migration in a flow field with
uniform temperature gradient at small and large Marangoni (Reynolds) numbers.
The drop is assumed to have only a slight axisymmetric deformation from a
sphere. It is identified that a conservative/nonconservative integral thermal
flux across the surface in the {\it steady} thermocapillary drop migration at
small/large Marangoni (Reynolds) numbers. The conservative flux confirms the
assumption of {\it quasi-steady} state in the thermocapillary drop migration at
small Marangoni (Reynolds) numbers. The nonconservative flux may well result
from the invalid assumption of {\it quasi-steady} state, which indicates that
the thermocapillary drop migration at large Marangoni (Reynolds) numbers cannot
reach {\it steady} state and is thus a {\it unsteady} process.Comment: 21 pages. arXiv admin note: text overlap with arXiv:1112.276
Habit Formation and Random Seating Assignment in Japanese Live-Concert Market
The Japanese concert market is distinct from live-concert markets in other countries because of its reliance on cheap tickets sold through the fan clubs and concert ticket lotteries. Most of the tickets of famous artists are sold through their fan clubs' pre-order lottery system at uniform prices instead of through third-party platforms at different prices. Such a strategy seems counterintuitive, as entertainment firms may explore additional profitability by making seats publicly available and varying ticket price with seat quality. By forming two theoretical models, we explore the pricing strategy of Japanese firms from two aspects: habit formation process and random seating assignment. From the first model, we conclude that, with habit formation, firms' overall optimal prices are lower than the first period optimal prices. From the second model, we find that random seating assignment with uniform price always yields less revenue than price differentiation. This result suggests that Japanese firms might use lotteries due to reasons other than profit maximization in the primary market.Bachelor of Art
Turbo-FLASH based arterial spin labeled perfusion MRI at 7 T.
Motivations of arterial spin labeling (ASL) at ultrahigh magnetic fields include prolonged blood T1 and greater signal-to-noise ratio (SNR). However, increased B0 and B1 inhomogeneities and increased specific absorption ratio (SAR) challenge practical ASL implementations. In this study, Turbo-FLASH (Fast Low Angle Shot) based pulsed and pseudo-continuous ASL sequences were performed at 7T, by taking advantage of the relatively low SAR and short TE of Turbo-FLASH that minimizes susceptibility artifacts. Consistent with theoretical predictions, the experimental data showed that Turbo-FLASH based ASL yielded approximately 4 times SNR gain at 7T compared to 3T. High quality perfusion images were obtained with an in-plane spatial resolution of 0.85×1.7 mm(2). A further functional MRI study of motor cortex activation precisely located the primary motor cortex to the precentral gyrus, with the same high spatial resolution. Finally, functional connectivity between left and right motor cortices as well as supplemental motor area were demonstrated using resting state perfusion images. Turbo-FLASH based ASL is a promising approach for perfusion imaging at 7T, which could provide novel approaches to high spatiotemporal resolution fMRI and to investigate the functional connectivity of brain networks at ultrahigh field
Dynamic optimal reinsurance and dividend-payout in finite time horizon
This paper studies a dynamic optimal reinsurance and dividend-payout problem
for an insurer in a finite time horizon. The goal of the insurer is to maximize
its expected cumulative discounted dividend payouts until bankruptcy or
maturity which comes earlier. The insurer is allowed to dynamically choose
reinsurance contracts over the whole time horizon. This is a mixed
singular-classical control problem and the corresponding
Hamilton-Jacobi-Bellman equation is a variational inequality with fully
nonlinear operator and with gradient constraint. The smoothness of
the value function and a comparison principle for its gradient function are
established by penalty approximation method. We find that the surplus-time
space can be divided into three non-overlapping regions by a
risk-magnitude-and-time-dependent reinsurance barrier and a time-dependent
dividend-payout barrier. The insurer should be exposed to higher risk as
surplus increases; exposed to all the risks once surplus upward crosses the
reinsurance barrier; and pay out all reserves in excess of the dividend-payout
barrier. The localities of these regions are explicitly estimated.Comment: 7 figure
Explicit Intensity Control for Accented Text-to-speech
Accented text-to-speech (TTS) synthesis seeks to generate speech with an
accent (L2) as a variant of the standard version (L1). How to control the
intensity of accent in the process of TTS is a very interesting research
direction, and has attracted more and more attention. Recent work design a
speaker-adversarial loss to disentangle the speaker and accent information, and
then adjust the loss weight to control the accent intensity. However, such a
control method lacks interpretability, and there is no direct correlation
between the controlling factor and natural accent intensity. To this end, this
paper propose a new intuitive and explicit accent intensity control scheme for
accented TTS. Specifically, we first extract the posterior probability, called
as ``goodness of pronunciation (GoP)'' from the L1 speech recognition model to
quantify the phoneme accent intensity for accented speech, then design a
FastSpeech2 based TTS model, named Ai-TTS, to take the accent intensity
expression into account during speech generation. Experiments show that the our
method outperforms the baseline model in terms of accent rendering and
intensity control.Comment: 5 pages, 3 figures. Submitted to ICASSP 2023. arXiv admin note: text
overlap with arXiv:2209.1080
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