Modeling of steady and time-dependent responses in filled, uncured, and crosslinked rubbers

Filled polymer systems have been a subject of interest for rheologists for several decades. Their applications range from paints and pigments to high performance composite materials. Presently, there is a lack of complete understanding of the behavior of these materials under varying kinematic and dynamic conditions. Moreover, there is a lack of a comprehensive theory, which can simultaneously describe the rheology of filled rubbers, their chemorheology, and their behavior in the final fully cured state. The present work is aimed at capturing a wide range of rheological (viscoelastic and kinetic) properties of filled rubbers with one set of constitutive/kinetic equations and a flexible relaxation spectrum. The various experiments covered are yield-flow transition in creep, shear start up responses, dynamic behavior in the melt state, and the changes during the cure stage. In the post cure state, the manifestations in Mullins stress softening-hysteresis and recovery, large strain stress relaxations, and dynamic behavior are also demonstrated. Finally, the non-linearities during large strain dynamic deformations, accompanied by non-isothermal, viscoelastic, and structure effects are exemplified. Received: 24 July 2000 Accepted: 13 November 2000     

SLP-IOR: An interactive model management system for stochastic linear programs

In this paper stochastic linear programming (SLP) is considered from the model management point of view. General model management issues specific to SLP are discussed in connection with their implementation in SLP-IOR. The central topic of the paper is SLP-IOR itself which is a model management system for SLP being under development by the authors. The presentation is concentrated on single and two stage models these being the model classes incorporated into the present version of SLP-IOR.     

High pressure solid–liquid equilibria of fatty acids

The solid–liquid phase diagrams of two binary mixtures of saturated fatty acids, formed by caprylic acid (C_8:0) + myristic acid (C_14:0) and lauric acid (C_12:0) + myristic acid (C_14:0), were measured using high pressure microscopy in the range of 0.1–90 MPa. It is shown that unlike for other long chain alkyl compounds such as alkanes the phase diagrams are only slightly affected by the pressure, even in very large pressure ranges such as studied in this work.     

高职院校技能竞赛与课程群建设的探讨与实践

针对高职教育技能竞赛和课程群建设间普遍存在着相互独立运行、沟通渠道不畅、缺乏促进机制等问题,提出了在技能竞赛与课程群建设间建立良性互动机制的构想,设计了互动机制的循环反馈调节模型,分析了互动要素的驱动关系,给出了互动机制在课程群建设中的实现思路和操作方法.     

Growth Modeling of Fiber Gratings: A Numerical Investigation

We have developed a simple method to analyze the growth process of fiber gratings (FGs) in the core of photorefractive optical fibers. It is based on the exponential saturation model and it takes into account the type of photosensitive fiber used, the exposure times, and the incident optical power. The photorefractive fiber has been characterized by two parameters: the saturation photoinduced refractive index change and the saturation energy, which can be obtained experimentally. We carry out a numerical investigation for the growth process of a uniform FG. The experimentally observed phenomena of shifting the Bragg optical frequency with exposure times and the appearance of higher-order Bragg resonances are predicted and discussed.     

一类半导体方程整体弱解的存在性

考虑激光照射的半导体方程，在初值n0,po∈L ^2(Ω）的条件下，证明了其混合初边值问题整体弱解的存在性。     

Multipurpose Professional Growth Sequence: The catwalk problem as a paradigmatic example

An important concern in mathematics teacher education is how to create learning opportunities for prospective and practicing teachers that make a difference in their professional growth as educators. The first purpose of this article is to describe one way of working with prospective and practicing teachers in a graduate mathematics education course that holds promise for positively influencing the way teachers think about mathematics, about student learning, and about mathematics teaching. Specifically, I use the “catwalk” task as an example of how a single problem can serve as the basis for a coherent sequence of professional learning experiences. A second purpose of this article is to provide background information that contextualizes the subsequent two articles, each of which details the positive influence of the catwalk task sequence on the authors’ professional growth.     

基于ObjectARX的机械零件三维实体造型

介绍了利用AutoCAD的二次开发工具ObjectARX开发机械零件三维实体造型的实现机制和关键技术，通过实例阐述了在ARX应用程序中三维实体造型的设计方法。     

数学模型的建立和应用

本文简要介绍了数学模型的产生过程,阐述了建立数学模型的步骤数学模型的类型以及数模的应用。