基于单片机的温度采集和无线传输系统设计

单片机属于一种微控制器,在很多领域都有广泛的应用。根据地震前兆水温观测的实际工作需要,设计了一种基于单片机的温度采集与无线传输系统,系统控制内核为STC89C52,结合DS18B20单线数字温度传感器,对温度数据进行采集和传输,并通过LLED数码管实时显示。无线传输系统方面,选择ZigBee无线通讯模块,能够实现单片机和上位机PC端数据的有效传输。     

无线通信在均化库取料机的应用研究

设计了应用于均化库取料机的无线通信模块,采用STC89C52RC单片机与nRF24L01无线模块作为主要构件。利用单片机程序控制单片机对自身特定端口状态进行采样后,控制nRF24L01无线模块将采样的结果通过无线方式传送给信息接收方,随后进入接收状态接收对方回馈的信息,循环工作就可以进行半双工无线通信。     

基于单片机的无线温度数据传输系统设计

基于STC89C52单片机,提出一种采用温度传感器DS18820和射频芯片nRF905的无线数据采集系统方案,利用LCD1602显示实时所测温度。完成了采集现场与监控装置的分离,实现了距离50m到100m的无线传输,且每10s定时发送所测温度,测量精度为0．5℃。     

基于nRF905的无线温度采集系统的设计

采用nRF905无线收发模块、DS18B20温度传感器,以AT89S52单片机为主控核心,设计了一种无线温度检测系统,采集到的温度数据通过电平转换芯片MAX232传到PC机。经测试表明:在同等条件下,系统误码率大小与传输距离有关,最大有效传输半径可达200 m;系统的温度测量范围为20~80℃,误差小于±0.2℃,满足预期要求。     

基于MSP430单片机的温度采集系统设计

随着现代科学技术的飞速发展,温度数据的采集与传输已经成为工农业生产中必不可缺的重要组成部分。本文设计了一个简易的温度数据采集及无线传输系统,本设计以MSP430单片机作为中央控制单元,采用DS18B20芯片采集温度数据,用NRF905无线射频控制芯片收发数据。     

基于nRF24L01的无线智能温度监测系统

提出了一种以无线传输模块nRF24L01和数字温度传感器DS18B20相结合的无线智能温度监测系统的设计方案.给出了系统的软硬件设计与实现.通过上位机管理软件的设计完成了对多点温度的采集和管理.以超低功耗和高性价比的设计方式解决了目前温度监测系统在有线方式下布线复杂、维护困难与数据传输不稳定的问题.通过实践表明该系统可应用于多种温度测量领域.     

基于单片机和nRF905SE的无线射频收发模块的系统设计

应用STC89C52RC单片机和nRF905SE无线射频器,设计了一种无线数据传输系统,该系统由发射模块和接收模块组成。实验表明,根据系统所设计的发射模块能够将上位机传输过来的数据经单片机处理后,通过nRF905SE发送出去。在接收模块中,nRF905SE则将数据正确接收后通过数码管显示出来,从而实现无线通信。     

基于DS18B20温度传感器的无线报警系统

本系统选用DS18B20温度传感器采集温度信息,采用STC89C52单片机做为主控芯片,处理并显示实时温度值。当温度超出预设范围便无线报警,可实现远程监控。该系统具有硬件结构简单、成本低廉、灵敏度高等优点。     

基于MCU和nRF24L01的图像无线传输设计

提出了基于STC89C54RD+微控制器和nRF24L01无线通信模块的近距离无线图像传输设计方案。详细介绍了系统硬件和软件的设计过程,实现了对图像的提取、无线传输和显示功能。最后通过实验测试了系统的可靠性和正确性,达到了设计目的。     

1-wire总线多点温度检测显示系统在Proteus中的仿真实现

本文利用Proteus软件设计了4通道环境温度检测显示系统,温度传感器采用Dallas公司的数字温度传感器DS18B20检测各通道温度数据,4通道温度数据经由1-wire总线传送至单片机STC89C52,温度数据经单片机处理后传送至液晶显示器LM032L显示。采用Keil软件和C51语言设计、编写单片机和多个DS18B20的通信程序流程以及显示程序流程。并通过Proteus软件仿真。     

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...     

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.     

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。     

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...     

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。     

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。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

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.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

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...