Journal of Advances in Applied Mathematics

Number 1, 2018

13
Partitioned computation for fluid-structure interaction with rigid body motion

Authors: Asim Timalsina, Gene Hou, Jin Wang

Abstract

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We present a new computational framework for fluid-structure interaction problems that involve rigid body motion. Based on a partitioned strategy, the fluid and structural dynamics are computed separately, and the solutions communicate at the interface. The immersed boundary method is employed to handle the fluid-structure interaction, and the direct-forcing technique is utilized to calculate the interaction force. In particular, the rigid body motion is directly and explicitly incorporated into the formulation and computation of the structural dynamics. We demonstrate our methodology by numerically simulating the motion of single and multiple rigid circular discs interacting with nonlinear viscous flow.

14
The Degree of Approximation and Converse Theorems with Exponential-Type Weights

Authors: Ryozi SAKAI

Abstract

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Let R = (−∞, ∞), and let Q ∈ C1 (R) : R → [0, ∞) be an even function, which is an exponent. We deal with the exponential-type weights w(x) = e −Q(x) , x ∈ R. In this paper, we consider the approximation problem with the weight w(x), and then we give some converse theorems, and investigate the smoothness of functions. We will also study the connections of the degree of approximation of a function between different norms. To do them we need to give the Nikolskii-type inequalities.

14
Research on the “Internet + Traffic” Development Index under the Requirement of Urban Traffic based on the Multiple Regression Model

Authors: Mingwei LI

Abstract

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The widespread application of “Internet +” technology has enlightened the problemsolving of the increasingly heavy traffic in China. Thus the “Internet + traffic” has been pushed to the leading edge. The numerous researches in the “Internet + traffic” field mainly focus on the strategies of transformation and upgrading the existing traffic system to a more “internet” way, few have ever concerned about the demands on developing “Internet + traffic” of each cities, which was usually treated as for granted. However, as this paper finds out, different cities, based on their urban traffic development, have different levels of “Internet + traffic” development demand. Therefore, in this paper we discuss the development index and construction demand degree of the “Internet + traffic”. In addition, we build the multiple regression model and select data of 36 principal cities in China to make clear the construction level and key development areas of “Internet + traffic” under the requirements of urban traffic. Additionally, the prediction model is provided to evaluate the construction degree of separate cities when developing “Internet + traffic”. At last, suggestions would be put forward for a better development of the “Internet + traffic”.