Numerical Methods for Solving Fractional Differential Equations

Department of Mathematical SciencesIn this thesis, several efficient numerical methods are proposed to solve initial value problems and boundary value problems of fractional di???erential equations. For fractional initial value problems, we propose a new type of the predictorevaluate-corrector-evaluate method based on the Caputo fractional derivative operator. Furthermore, we propose a new type of the Caputo fractional derivative operator that does not have a di???erential form of a solution. However, with some fractional orders, there are problems that a solution blows up and the scheme has a low convergence. Thus, we identify new treatments for these values. Then, we can expect a significant improvement for all fractional orders. The advantages and improvements are shown by testing various numerical examples. For fractional BVPs, we propose an explicit method that dramatically reduces the computational time for solving a dense matrix system. Moreover, by adopting high-order predictor-corrector methods which have uniform convergence rates O(h2) or O(h3) for all fractional orders [8], we propose a second-order method and a third-order method by using the Newton???s method and the Halley method, respectively. We show its advantage by testing various numerical examples.clos

The dividend policy of U.S. owned foreign subsidiaries.

ManagementDoctor of Philosophy (Ph.D.

Effective management of EFL(Executive Floor): An Investigation into quality-management on service

In a recent days the hotel industries, coping with the change of management environment swiftly, are turning to pursue the quality-management of service. The merchandises of hotel are fundamentally rooms, food and beverage, and subsidiary facilities. The hotel in modern times, laying stress on service radically, have being endeavored to minimize the difference between the actual service offered and the expectation of customers on it. Especially because of the essential qualities in hotel, the need of quality-management is demanded to increase. The EFL in hotel is not only the place where the difficulty of producing the merchandise focused on quality is reflected but also the department in which the endeavor of keeping up the service quality and the effective quality-management is demanded. The study on the quality-management, however, is not enough to satisfy the customers and the men engaging in hotels as well as the scholars. The purpose of this study are follows ; 1 . To disclose the signification of EFL in hotel management through the investigation into the conception, the importance and the character of EFL. 2. To know how to control the human resources to realize the improvement the quality service for customers and the quality-management of EFL in hotel. 3. To search the management and problem of EFL in hotel. Therefore, this study is being concentrating on the effective management of EFL and quality service to visualize the long-term profit in hotel business. Recently the environment around the hotel business is rapidly changing, especially in EFL market plan, and so the quality-management of EFL in hotel is regarded as the strategic enterprise to achieve the abiding improvement and development in hotel industries. Thus, the alternative proposal of EFL in hotel is as follows ; First, the EFL in hotel must be focused on offering the individual and differentiated service to induce the positive direction in perceived benefit of the customers psychologically. Second, the EFL in hotel should be aimed to maximize the VAT of hotel in a long-term rather than the statistical profit in a provisional period. Third, to succeed in improving EFL business, it should be necessary for the men engaging in hotel to take the special education, specially in quality service, for the proper education is essential to satisfy the customer\u27s expectation. Fourth, to satisfy EFL, it is very important for all men engaging in hotel to accept the conception of EFL at the unified mind, it is becoming the center of hotel business. Furthermore, the competition in hotel business is focused not only on quantification but also on qualification. I hope that the various studies on the theme will be continued to develop the hotel industries, focusing on customer\u27s satisfaction

Multiphysics Modeling of Surface Diffusion Coupled with Large Deformation in 3D Solids

We present a comprehensive theoretical and computational model that explores the behavior of a thin hydrated film bonded to a non-hydrated / impermeable soft substrate in the context of surface and bulk elasticity coupled with surface diffusion kinetics. This type of coupling can manifests as an integral aspect in diverse engineering processes encountered in optical interference coatings, tissue engineering, soft electronics, and can prove important in design process for the next generation of sensors and actuators, especially as the focus is shifted to systems in smaller lengthscales. The intricate interplay between solvent diffusion and deformation of the film is governed by surface poroelasticity, and the viscoelastic deformation of the substrate. While existing methodologies offer tools for studying coupled poroelasticity involving solvent diffusion and network deformation, there exists a gap in understanding how coupled poroelastic processes occurring in a film attached to the boundary of a highly deformable solid can influence its response. In this study, we introduce a non-equilibrium thermodynamics formulation encompassing the multiphysical processes of surface poroelasticity and bulk viscoelasticity, complemented by a corresponding finite element implementation. Our approach captures the complex dynamics between the finite deformation of the substrate and solvent diffusion on the surface. This work contributes valuable insights, particularly in scenarios where the coupling of surface diffusion kinetics and substrate elasticity is an important design factor.Comment: 20 pages, 8 figues. arXiv admin note: text overlap with arXiv:2305.0880

Ricochet of Spheres on Sand of Various Temperature

The debris generated by the explosion of a building or ammunition is flown far away through the ricochet phenomenon. The debris contains a very large amount of energy, and a risk factor surrounding it may be applied. The safety distance from debris is set from experiments or FEM analysis. The ricochet of debris is affected not only by the initial conditions of the debris, but also by the conditions of the medium. In this paper, the effect of sand temperature on the ricochet of sphere projectiles was investigated through experiments and FEM, by measuring the shear stress and internal friction angle when the sand temperature increases. As the temperature of the sand increases, the shear stress and the internal friction angle decrease, and the penetration depth of the projectile increases. As the depth of penetration becomes longer, the kinetic energy is lost more by the friction force with the sand and, the sphere projectile speed decreases more. This is mainly caused by the energy loss of the projectile, so the kinetic energy of the ricocheted projectile is reduced. Therefore, when setting the optimized inhabited building distance (IBD), the conditions of the medium should be taken into account

DailyTalk: Spoken Dialogue Dataset for Conversational Text-to-Speech

The majority of current Text-to-Speech (TTS) datasets, which are collections of individual utterances, contain few conversational aspects. In this paper, we introduce DailyTalk, a high-quality conversational speech dataset designed for conversational TTS. We sampled, modified, and recorded 2,541 dialogues from the open-domain dialogue dataset DailyDialog inheriting its annotated attributes. On top of our dataset, we extend prior work as our baseline, where a non-autoregressive TTS is conditioned on historical information in a dialogue. From the baseline experiment with both general and our novel metrics, we show that DailyTalk can be used as a general TTS dataset, and more than that, our baseline can represent contextual information from DailyTalk. The DailyTalk dataset and baseline code are freely available for academic use with CC-BY-SA 4.0 license.Comment: 5 pages, 1 figures, 4 tables. Accepted to ICASSP 202