DTU模块在无线抄表系统中的开发与应用

由于利用公网实现无线抄表的需要,从而设计并且开发了基于 GPRS 网络的 DTU 模块,实现了 DTU 模块在抄表系统中的应用.介绍了 DTU 模块终端的技术要求、GPRS 模块及组网、DTU 的硬件电路设计方案,以及 PCB 板的抗干扰/可靠性设计、通讯模块软件设计,并探讨 DTU 模块 AT 指令交互功能及 DTU 模块在无线抄表中的开发应用     

GPRS DTU在工程机械远程监控系统中的应用研究

本文以宏电公司的H7118C GPRS DTU为例介绍了GPRS DTU的工作原理，并详细说明了GPRS技术在工程机械远程监控系统中的应用及实现方法。     

基于GPRS的无线水质自动监测系统的研究

该系统在传统工艺的基础上利用AT89C51单片机和基于GPRS的新型无线通讯模块相结合实现了水质自动监测系统的设计。下位机水质参数处理采用了信息融合技术,提高了检测精度;利用串口并通过DTU模块将数据传送至水质监控中心,快速准确地实现对水质状况的实时监测。系统功耗小、成本低、实时在线、不受地理位置限制等优点。     

GPRS/GSM自动切换技术在水情自动测报系统中的研究与应用

本文在介绍GPRS无线数据传输终端SaroGPRS DTU工作原理的基础上，对利用SaroGPRS DTU无线数据终端实现GPRS／GSM传输水情数据的自动切换关键技术进行了研究，并介绍了其推广应用情况。     

三菱PLC和四信DTU在供热控制系统中的应用

利用三菱PLC和GPRS无线通信技术,将热力公司和所有换热站现场的全部数据传送到监控中心,同时将中心的控制信号有效地发送给换热站。此外还介绍了GPRS IP MODEM(GPRS DTU)的工作流程,分析了三菱FX2N系列PLC与DTU通信的PLC程序设计。该控制方式已在怀来县热力公司投入使用,实现了远程控制与本地控制的有效结合。     

基于GR47通信模块的短信远程家电控制系统

针对很多GSM模块可以通过GSM/GPRS接入互联网这一特点,设计了一个以索尼爱立信公司的GR47无线模块作为接收模块,89C51作为主控制器的家电短信远程控制系统.介绍了该系统的硬件构成,详细描述了在PDU模式下用AT命令实现短信对家电的远程控制的过程,以及在VC 6.0环境下系统软件的设计流程.研究结果表明,该系统具有广阔的推广应用前景.     

MC39i在车载GPS终端的应用

通讯模块是车载GPS终端的重要组成部分,是终端与上端监控系统进行信息交流的唯一通道.ARM 7 CPU通过AT命令对GPRS模块进行控制,从而实现SOCKET通信.文章介绍了Siemens MC39i通信模块的AT命令设计、与SIM卡连接设计等.     

基于ARM的远程无线瓦斯监控系统

针对传统瓦斯监控系统的不足,系统基于ARM开发平台,结合GPRS DTU制作了一种新的远程无线瓦斯监控系统。根据系统设计的需要,制作了嵌入式Linux内核以及根文件系统。ARM与GPRS DTU通过串口进行数据传输,将瓦斯传感器采集到的数据传给GPRS DTU,利用TCP/IP进行无线传输,将数据及时传送到监控中心。该系统可以根据工作需要进行工作模式的设置,可以通过短信和电话进行控制,方便了管理和控制。实验证明,该系统可以对煤矿瓦斯浓度进行远程无线监控。     

一种新型GPRS分布式数据采集系统的研究和设计

传统GPKS分布式数据采集系统中GPRS DTU无法被动连接访问而必须永远在线,造成通讯资源浪费和数据中心网络端口拥挤.本文提出基于GPKS的分布式数据采集系统的新方案,该方案DTU硬件采用AKM7结合GTM900通讯模块,运用WAP PUSH技术,实现GPKS DTU的被动连接访问,并可以构建冗余数据中心.     

基于GPRS模块的嵌入式无线电话机

介绍基于GPRS模块、LPC2138微控制器构成的无线电话机,该无线电话机可以通过GPRS网络与移动电话、固定电话等完成实时语音通信。文章从硬件设计和软件编程两个方面介绍了系统的AT指令传输、拨号等过程。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...