On the Green's matrices of strongly parabolic systems of second order

We establish existence and various estimates of fundamental matrices and Green's matrices for divergence form, second order strongly parabolic systems in arbitrary cylindrical domains under the assumption that solutions of the systems satisfy an interior H\"{o}lder continuity estimate. We present a unified approach valid for both the scalar and the vectorial cases.Comment: 33 page

An Analysis of Risk Management Practices and Legal Considerations in South Korean Club Sports

In light of the fact that club sport participation in South Korea is increasing in an unprecedented pace, the primary objective of the study was to establish the management status of sports clubs. Specifically, this study investigated a broad spectrum of issues concerning safety issues with regards to club sport participation, including the status of injury/accident and litigation, risk management practices, and legal considerations. Additionally, the study researched the association between the institutional demographic factors of sport clubs and various risk management variables. The study was conducted by using the self-developed 36-item survey that include demographic information, injury/accident and litigation status, and risk management practices/legal considerations. The questionnaire was primarily developed from the American literatures in the field of sport law and risk management, and was validated by several experts in the field of sport management. The distribution of questionnaire was accomplished by five assigned survey couriers who visited sport facilities in South Korea to collect data from the club sport managers. The findings of this study represented 304 sport clubs across South Korea. Descriptive statistics, Analysis of Variances (ANOVA), t-test, and Chi-square tests were utilized to answer the proposed research questions. Overall, the results of this study revealed that risk management practices were not conducted in a sufficient and consistent manner, even though many sport club managers experienced or observed a significant number of injuries/accidents during the course of club participation. However, a majority of injuries/accidents did not resulted in litigation. Furthermore, several relationships were reported between sport clubs institutional demographic factors and risk management practices. Some of the factors affecting higher responses of risk management practices were contact sports, infrequent club meetings, club with fewer members, club with younger age groups, shorter longevity of club, urbanized location of club, and academic ownership of club\u27s host facility. The study may contribute to assist building the basic framework for law and policy issues with regards to managing sport organizations in South Korea. Through the formulation of the relevant risk management practices for sport clubs, it is hoped that preventable injuries and possible litigation are avoided in the future

Origin of Non-axisymmetric Features of Virgo Cluster Early-type Dwarf Galaxies. I. Bar Formation and Recurrent Buckling

A fraction of early-type dwarf galaxies in the Virgo cluster have a disk component and even possess disk features such as bar, lens, and spiral arms. In this study, we construct 15 galaxy models that resemble VCC856, considered to be an infalling progenitor of disk dwarf galaxies, within observational error ranges, and use $N$-body simulations to study their long-term dynamical evolution in isolation as well as the formation of bar in them. We find that dwarf disk galaxies readily form bars unless they have an excessively concentrated halo or a hot disk. This suggests that infalling dwarf disk galaxies are intrinsically unstable to bar formation, even without any external perturbation, accounting for a population of barred dwarf galaxies in the outskirts of the Virgo cluster. The bars form earlier and stronger in galaxies with a lower fraction of counter-streaming motions, lower halo concentration, lower velocity anisotropy, and thinner disk. Similarly to normal disk galaxies, dwarf disk galaxies also undergo recurrent buckling instabilities. The first buckling instability tends to shorten the bar and to thicken the disk, and drives a dynamical transition in the bar pattern speed as well as mass inflow rate. In nine models, the bars regrow after the mild first buckling instability due to the efficient transfer of disk angular momentum to the halo, and are subject to recurrent buckling instabilities to turn into X-shaped bulges

FloWaveNet : A Generative Flow for Raw Audio

Most modern text-to-speech architectures use a WaveNet vocoder for synthesizing high-fidelity waveform audio, but there have been limitations, such as high inference time, in its practical application due to its ancestral sampling scheme. The recently suggested Parallel WaveNet and ClariNet have achieved real-time audio synthesis capability by incorporating inverse autoregressive flow for parallel sampling. However, these approaches require a two-stage training pipeline with a well-trained teacher network and can only produce natural sound by using probability distillation along with auxiliary loss terms. We propose FloWaveNet, a flow-based generative model for raw audio synthesis. FloWaveNet requires only a single-stage training procedure and a single maximum likelihood loss, without any additional auxiliary terms, and it is inherently parallel due to the characteristics of generative flow. The model can efficiently sample raw audio in real-time, with clarity comparable to previous two-stage parallel models. The code and samples for all models, including our FloWaveNet, are publicly available.Comment: 9 pages, ICML'201

A Schedulability Analysis Framework for Real-time Infrastructure Systems Managing Heterogeneous Resources

REACTION 2012. 1st International workshop on Real-time and distributed computing in emerging applications. December 4th, 2012, San Juan, Puerto Rico.Electricity generating systems, such as smart grid systems, and water management systems are infrastructure systems that manage resources critical to human life. In the systems, resources are produced and managed to supply them to various consumers, such as building, car, factory, and household, according to their needs and priorities. Reliable supply of resources depends not only on sufficient production of resources but also on reliable sharing of resource supply facilities. This paper presents a schedulability analysis framework. A prominent characteristic of the framework is that it considers at once the two types of resources, i.e. consumable resources, such as electricity, energy, and water, and sharable resources, such as pipelines, storages, and processors, are considered. To apply a formal approach to schedulability analysis of infrastructure system, this paper classifies the types of resources and real-time jobs for infrastructure systems. Then based on the classification , it presents an architectural model and a schedulability analysis framework.This research was supported by the KAIST High Risk High Return Project (HRHRP)