Stress-deformable state of isotropic double curved shell with internal cracks and a circular hole

This work is devoted to the stress–strain state of isotropic double curved shell with defect system. The construction is weakened by two non-through thickness (internal) cracks of different length and by a circular hole located between cracks. In this study we use the line-spring model. Within the framework of this model cracks are modeled as mathematical cuts of shell’s middle surface. This leads to a two-dimensional problem. The problem is reduced to a system of eight boundary integral equations. To ensure the uniqueness of solution an additional equation is added. In the numerical solution of the problem special quadrature formulas for singular integrals of Cauchy type and the finite difference method are applied. The influence of defects on each other for double curved shell has been investigated. The given theoretical results can be used for the calculation of structural elements with holes, cracks on the strength and fracture toughness in various branches of engineering.     

Design and validation of robotic bionic eye with multiple flexible ropes parallel mechanism inspired by oculomotor law

Producing a stable and agile bionic eye for visual image acquisition in robotics is a challenging task. In this paper, we design a bionic eye with mirror-symmetric distribution and cross-connection of flexible ropes. This mechanism is based on oculomotor law and the physiological structure of the extraocular muscles (EOMs). Specifically, the basic structural parameters are determined by Listing’s law, and the unique connection of the flexible ropes can realize the functions of the recti and oblique muscles. Furthermore, to mimic the trochlea structure, a pulley mechanism is constructed to permit the free movement of the flexible ropes. Through simulation and physical experiments, it is demonstrated that the bionic eye mechanism can move with agility under the structural parameters. The experimental results indicate that the proposed bionic eye mechanism has a superior motion accuracy of 2.798 mm, which is 6.7% of the maximum motion distance, and the repeatable accuracy of the mechanism can up to 0.210 mm.     

Research on Circular Area Search algorithm of multi-robot service based on SOA cloud platform

Considering autonomous mobile robots with a variety of specific functions as a kind of service, when there are many types and quantities of services and the density of regional services is large, proposing an algorithm of Circular Area Search (CAS) because of the problem of multi-robot service scheduling in various areas. Firstly, Django is used as the web framework to build the Service-Oriented Architecture (SOA) multi-robot service cloud platform, which is the basic platform for multi-service combination. Then, the service type, the latitude and longitude and the scoring parameters of the service are selected as the service search metrics to design the CAS algorithm that based on the existing service information registered in MySQL and the Gaode Map for screening optimal service, and then providing the service applicant with the best service. Finally, the service applicant applies for the self-driving tour service as an example to perform performance simulation test on the proposed CAS algorithm. The results show that the CAS algorithm of the multi-robot service cloud platform proposed in this paper is practical compared to the global search. And compared with the Greedy Algorithm experiment, the service search time is reduced about 58% compared with the Greedy Algorithm, which verifies the efficiency of CAS algorithm.     

一种用于微波射频识别卡的圆极化微带天线

本文设计了一种用于微波非接触式射频识别卡的圆极化微带天线 ,采用AnsoftEnsemble7.0和Optimetrics模块分别进行仿真和优化 ,使输入、输出端口驻波比 ,左、右旋圆极化隔离度等参数满足系统性能要求。对加工的样品进行测试 ,结果显示 ,天线中心谐振频率为 5 .8GHz,左、右旋圆极化隔离度约 2 0dB ,天线有效方向角6 0° ,天线增益为 5dBi,达到实用化要求     

A New Comb Circular Polarizer Suitable for Millimeter‐Band Application

This letter presents a new polarizer which has a simple comb structure inside a circular waveguide. The electrical performance of the proposed comb polarizer is optimized by a circular waveguide radius and by the physical parameters of the comb plates. This polarizer is suitable for providing good performance in millimeter‐band application because of its simple structure and low fabrication cost. In our experiments the dual‐band comb polarizer designed in band 1(K) and band 2(Ka) showed good electrical performance without any tuning elements.     

结构振动试验转接器的设计及安装问题

一些产品及其相关部件在作振动试验时，由于产品的外形或特殊要求不能直接安装在振动台面上，需要通过特别设计的转接器（夹具）来进行连接，这种夹具实际上是一种附加结构，它作为台面与试件之间的中介，如设置不当将影响振动试验结果的可靠性。本文通过对某事例的分析与研究，从试验频带、允许误差、跟随条件以及安装共振频率等方面阐明与讨论了相关夹具的特性、设计原则与安装等问题。     

新型低压抽屉式开关柜在冶金系统的应用

介绍新型低压抽屉式开关柜的结构性能和特点，并与早期低压柜作了比较。阐述了新型低压抽屉式开关柜在冶金系统应用中的几点改进情况。     

Optimal H∞ general distance problem with degree constraint

In this paper the optimal H_∞, general distance problem, for continuous-time systems, with a prescribed degree on the solution is studied. The approach is based on designing the Hankel singular values using an imbedding idea. The problem is first imbedded into another problem with desirable characteristics on the Hankel singular values, then the solution to the original problem is retracted via a compression. The result is applicable to both the one-block and the four-block problems. A special case is given for illustration.     

2Mbit/s高速信令链路在移动通信七号信令网中的应用

通过对2Mbit/s高速信令链路原理、特点的介绍，阐明了该技术在现阶段使用的实际意义，并给出了2Mbit/s高速信令链路在移动通信七号信令网中的应用。