On the homomorphisms of power-set <Emphasis Type="Italic">Q</Emphasis>-algebras

We continue the study of homomorphisms between power-set Q-algebras. First, by means of decomposed ul-Q-relations between ordered semigroups we give a general characterization for the homomorphisms between power-set Q-algebras. Also, we consider a new category OSGRP whose objects are ordered semigroups and whose morphisms are decomposed ul-Q-relations, and discuss the relationship between the category OSGRP and the category Q-Alg of Q-algebras.     

TV‐like regularization for backward parabolic problems

This paper investigates an inverse problem for parabolic equations backward in time, which is solved by total‐variation‐like (TV‐like, in abbreviation) regularization method with cost function ∥u_x∥². The existence, uniqueness and stability estimate for the regularization problem are deduced in the linear case. For numerical illustration, the variational adjoint method, which presents a simple method to derive the gradient of the optimization functional, is introduced to reconstruct the unknown initial condition for both linear and nonlinear parabolic equations. The conjugate gradient method is used to iteratively search for the optimal approximation. Numerical results validate the feasibility and effectiveness of the proposed algorithm. Copyright © 2016 John Wiley & Sons, Ltd.     

The double-light-beam method in three-dimensional scattered-light photoelasticity

This paper presents a new scattered-light photoelasticity technique which may be called the double-light-beam measurement method. Principal-stress directions and relative retardations related to the principal-stress differences can be measured at any point within an ordinary three-dimensional photoelastic model by this method. This method does not need double loading and the quantities to be measured depend only on the relative light intensity. Moreover, the output signals alternate, providing improved accuracy and stability. If supported by an appropriate program-control and digital processing system, the double-light-beam method can be used to quickly determine the internal stress distribution in ordinary three-dimensional photoelastic models.     

SYNTHESIS AND CHARACTERIZATION OF SURFACE-HYPERBRANCHED MAGNETITE NANOPARTICLE FOR BOVINE SERUM ALBUMIN IMMOBILIZATION

A hyperbranched polyamidoamine polymer was synthesized on the surface of magnetite nanoparticles to enhance bovine serum albumin (BSA) immobilization efficiency. The amount of immobilized bovine serum albumin (BSA) on the surface-hyperbranched magnetite nanoparticle was up to 2.5 times as much as that of magnetite nanoparticle modified with only amino silane.     

Relationship between bearing capacity and depth of soft layer of paddy fields in South China

The bearing capacity of paddy field in South China was measured with a kind of penetrometer. A straight line relationship is valuable in summarizing the dependence of bearing capacity on depth of soft soil layer.     

An investigation on the lift force of a wing pitching in dynamic stall for a comfort control vessel

On the basis of a comfort control system for ocean vessels, the control forces and moments in the form of lift forces from active wings are of important interest. In an ocean vessel comfort control system, active wings or fins are commonly used and constantly adjust their angles of attack to produce optimal sea-keeping conditions. The unsteady nature of the flow field around a wing, and the behaviour of the generated lift force must be understood in order to optimize the comfort control system. This paper presents experimental data on the flow past a pitching wing, paying particular attention to the lagging effects between the fluid dynamic lift force and the motion of the wing at large angles of attack as a function of peak angle of attack and reduced frequency of oscillation. The range of motion investigated has been chosen according to the applicability of a comfort control wing surface. Numerical data is also included to aid explanation on some of the witnessed phenomena.     

Nonlocal interaction of a dislocation with a crack

Summary Based on the classical stress analysis, the stress field of a screw dislocation near a semi-infinite crack is investigated by a conformal mapping method. The classical image force on the dislocation due to the crack is presented by the obtained classical image stress. To eliminate the singularity of the stress field at the crack tip, the nonlocal elasticity theory is adopted. A maximum of the image stress is found near the crack tip and the nonlocal image force is then acquired by the obtained nonlocal stress field. Both the stress and the image force show much difference from the classical ones and seem to be more reasonable physically.

---

Nichtlokale Wechselwirkung zwischen einer Versetzung und einem Riß

Übersicht Basierend auf der klassischen Spannungsanalyse einer Schraubenversetzung neben einem halb-unendlichen Riß mittels einer konformen Abbildung wird die klassische Bildkraft auf die Schraubenversetzung als Folge des Risses vorgestellt. Um die Spannungssingularitäten neben der Rißspitze zu beseitigen, wird die nichtlokale Elastizitätstheorie herangezogen, mittels ihrer wird das Maximum der Spannung neben dem Riß gefunden und die nichtlokale Bildkraft ermittelt. Die Spannungen und die Bildkraft der nichtlokalen Elastizitätstheorie zeigen große Unterschiede gegenüber der klassischen Analyse und sind physikalisch vernünftiger.

     

含孔洞粘塑性材料剪切带的正交性条件

本文通过对粘塑性材料剪切带中含孔洞的代表体元的细观力学分析，得到了剪切带的宏观本构热和本构关系。采用上限方法，给出了多孔粘塑性材料正交流动法则存在的条件。     

线性时滞系统的离散最优控制

介绍了对线性时滞系统进行最优控制的设计，将具有时滞控制的线性系统离散后引入增广状态向量。获得不显含时滞的差分方程，根据时滞量的两种分类情况采用连续和离散形式的性能指标函数导出了最优控制律。控制律包含当前状态和此前若干步状态向量的叠加，最优控制律直接从时滞方程中得到，可保证系统的稳定性，此方法亦适用于大时滞的情况。数值算例验证了控制策略的有效性。     

双路激光混沌复用系统的混沌同步及安全性能研究

针对一种新型的双路激光混沌复用系统, 建立相应的速率方程模型, 详细分析了两个主激光器的单个参数失配、多个参数同时失配、反馈强度差异以及频率失谐对混沌同步性能的影响, 并对此复用系统的安全性能和频谱性能进行了研究. 研究结果表明: 采用参数失配方案, 通过合理选择两个主激光器的参数, 可以保证两个主激光器之间的同步性能较差而两对主从激光器间实现高品质的混沌同步, 因此满足双路激光混沌复用的条件; 两个主激光器之间的参数失配对它们之间的同步性能影响较大, 然而对配对主从激光器间同步性能的影响并不明显, 进一步说明参数失配方案的有效性和可行性. 另外, 通过自相关函数和频谱分别分析混沌复用信号的时域和频域特征, 发现双路激光混沌复用系统可提供更高的安全性.