STEADY SOLUTIONS OF THE OPTICAL SOLITON EQUATION WITH A NONLINEAR RESPONSE DELAY TERM

The exact solution of the optical soliton equation with a nonlinear response delay term has been obtained by using the method of separating variables. The new type of optical solitary wave solution, which is quite different from the bright and dark soliton solutions, has been found for a special case.     

蜀葵花紫色素的提取及其稳定性研究

从蜀葵花瓣中提取的紫色素是一种安全无害的天然染料,本文对蜀葵花中的紫色素的提取及稳定性的研究作了介绍。     

线性强化材料索网的振动分析

讨论了线性强化材料索网振动问题,用分离变量函数导出了具有矩形底面的索网结构的自振圆频率。     

Productivity of tillage loosening and separating machines in an aggregate with tractors of various capacities

Currently, chemical methods of weed control are increasingly being replaced by mechanical weeding. One of the promising mechanical devices for weed control is a rotary loosening and separating stratifier. This tillage machine can provide high quality tillage to a depth of up to 18 cm. Its performance is determined by the width of the grip of the gun and the speed of movement and is limited by the traction capabilities of the tractor. Using the Goryachkin formula for the traction resistance of a tillage machine, the authors obtained the dependence of productivity on the width of the grip and the speed of movement at different depths of tillage. The obtained dependencies on the example of tractors John Deere 8330, HTZ 16131-05 and MTZ 1523.3 showed the presence of a pronounced maximum, which led to the solution of the optimization problem. The article presents a method for calculating the optimal width of the grip and the speed of movement that ensure the maximum productivity of the tillage machine, depending on the depth of processing and the specific resistance of the soil. The use of optimal parameters of the tillage machine allows you to increase its productivity by 2–3 times.     

Turbulent separated reattached flow in a two-dimensional curved-wall diffuser

A turbulent separation-reattachment flow in a two-dimensional asymmetrical curved-wall diffuser is studied by a two-dimensional laser doppler velocimeter. The turbulent boundary layer separates on the lower curved wall under strong pressure gradient and then reattaches on a parallel channel. At the inlet of the diffuser, Reynolds number based on the diffuser height is 1.2×10⁵ and the velocity is 25.2m/s. The results of experiments are presented and analyzed in new defined streamline-aligned coordinates. The experiment shows that after Transitory Detachment Reynolds shear stress is negative in the near-wall backflow region. Their characteristics are approximately the same as in simple turbulent shear layers near the maximum Reynolds shear stress. A scale is formed using the maximum Reynolds shear stresses. It is found that a Reynolds shear stress similarity exists from separation to reattachment and the Schofield-Perry velocity law exists in the forward shear flow. Both profiles are used in the experimental work that leads to the design of a new eddy-viscosity model. The length scale is taken from that developed by Schofield and Perry. The composite velocity scale is formed by the maximum Reynolds shear stress and the Schofield-Perry velocity scale as well as the edge velocity of the boundary layer. The results of these experiments are presented in this paper.     

液固旋流器分离效率的研究

对分离效率与液相流速、油水比例和旋流器级数之间的关系进行了系统的实验研究. 通过受力分 析从理论上对细颗粒易受参数影响的原因进行了阐述，并根据量纲分析和实验数据得到了分 离效率与$Re$数和$St$数之间的函数关系. 在此基础上，对液固旋流器的现 场应用提出了有价值的建议.     

贴片光弹性应力分离的一种新方法

本文介绍了在贴片光弹测试中分离主应力的一种新方法.它是借助于一种电容传感器,通过测定主应变之和从而达到分离主应力的目的.     

Sur la séparation des racines des polynômes et une question de Sprindžuk

Résumé Nous établissons une nouvelle minoration de la distance entre deux racines d’un polynôme à coefficients entiers, que nous appliquons à une question de théorie métrique des nombres posée par Sprindžuk.We establish a new lower bound for the distance between two roots of an integer polynomial. We apply it to a question in metric number theory posed by Sprindžuk.2000 Mathematics Subject Classification: Primary—11C08     

证券投资基金管理人选择中的信号传递博弈

本文通过对证券投资基金这种资金运作方式的分析和研究,结合信号传递博弈模型,提出一种对资金管理人投资能力的评估方法.主要分析基金管理人的努力成本对最后投资能力评估结果的影响,为投资人选择基金管理人提供新的思路,也为基金管理人争取融资成功提供一定的帮助.     

基于分离指标的宽阻带低通滤波器设计

常见的开路短截线和阶跃阻抗结构在微带低通器设计中较为成熟,但是这些结构的低通滤波器受到寄生通带的影响,阻带不够宽。提出了一种基于分离指标的宽阻带低通滤波器设计方法,利用计算机仿真软件ADS,对常见的阶跃阻抗低通滤波器进行结构改进。该方法将低通滤波器设计指标重点分为滚降率和宽阻带抑制两部分,分别利用椭圆滤波器和巴特沃斯滤波器的本身特性实现设计目的,最后进行级联优化。此结构综合设计方法简单严谨,易于实现,改进的低通滤波器性能优越,实现了宽阻带的设计需求,通带0~3GHz,插入损耗<0.5dB,阻带4~12GHz,抑制>45dB。