基于1-wire总线的温度数据采集与硬件设计

目的是要实现采用1-wire的数字式温度传感器DS18B20和单片机组成温度的数据采集与控制系统。介绍了该系统的工作原理和设计方法,并设计了使用DS18B20和AT89S51单片机的温度测量控制系统的硬件电路和软件编程,包括温度的采集、显示及报警控制等功能。系统结构简单、精度高、传输距离远、抗干扰能力强、可扩展性好,应用前景广阔。     

数字温度传感器DS18B20的应用

介绍了一种新型数字式温度传感器DS18B20，并用DS18B20和AT89C2051单片机开发研制了一种自动温度测控系统，该系统具有实用性强、测量精度高、可靠性高等特点。     

智能温度传感器DS18B20及其应用

针对目前采用的热敏电阻测量方法,提出了采用单总线数字式温度传感器DS18B20和单片机组成的新型智能温度测量仪。介绍了DS18B20的结构和工作原理,以及单总线工作原理,给出了由51单片机和DS18B20构成的单总线温度测量仪的硬件电路及程序设计。经试验基于单总线器件DS18B20的温度测量仪,具有测量准确、测温范围宽、体积小、控制方便等优点。     

DS18B20高精度多点温度检测显示系统

介绍一种基于DS18B20的多路温度检测显示系统。该系统以SPCE061A单片机作为主控芯片,采用一线温度传感器DS18B20实现多路温度的检测,测量精度可以达到0.1℃。该系统采用了128×64点阵式液晶显示模块SPLC501作为显示器,形象直观的显示各路设备名称及温度值。     

简易水温控制系统

本文设计了一个基于AT89S52单片机控制的水温控制系统,由下位机、上位机、和通讯网络三部分组成。下位机是基于单片机AT89S52和温度传感器DS18B20的高精度数据采集系统,功能是对温度的检测与输出控制。上位机采用计算机,与下位机进行数据信息的交互,并显示各路温度值及其曲线、控制参数、设定值等。其中,温度检测单元和可控硅调功控温单元是本文的设计重点。     

嵌入式液压油温控制系统的开发与应用

基于单片机的液压油温控制系统,用户可设置系统要保持的温度,数字温度传感器DS 18B20进行温度采集,数码管实时显示温度,程序对热交换器进行控制,达到自动控制油温稳定的目的.系统可单独作为液压油温控制系统、车载式液压油温控制系统使用,结构简单、成本低.     

由DS18B20构成的单线多点滑油温度监测系统设计

介绍了数字式温度传感器DS18B20的工作特点与工作原理,利用DS18B20的单线总线数字输出的特点和单片机技术,给出了一种基于DS18B20构成的单线多点滑油温度监测系统的硬件结构和软件流程,测试结果表明该系统能够有效地监测滑油温度,具有操作方便、接口简单、成本低、性能可靠等优点.     

基于DS18B20&DS12C887的热水器智能控制器的设计

该系统是在现有太阳能热水器的基础上开发的.以AT89C52单片机为控制核心,采用智能温度传感器DS18B20和DS12C887高精度实时时钟,设计了一种太阳能热水器智能控制器.阐述了系统的工作原理,并给出了硬件电路的原理图和软件的流程图.     

GPS共视接收机恒温系统的研制

温度变化对于利用GPS共视技术进行高精度远程时间比对的影响是不容忽视的.结合GPS共视接收机的工作特点,研制了与之相适应的温度控制系统.该系统使用数字式温度传感器DS1624为测温器件,选用自适应PID控制算法为系统温度控制算法,电路设计上采用基于I2C总线设计和防电磁干扰设计;因此系统具有电磁干扰小、实时性好、可靠性高和控温精度高等特点.测试结果表明该系统控温精度可达5℃,可满足GPS共视接收机的工作需求.     

基于STC89C52单片机的超声波测距设计

超声波测距由于使用方便、可靠性强,广泛应用于各行各业中。详细介绍了超声波测距原理和基于STC89C52单片机控制的超声波测距系统,超声波模块选用HC-SR04,考虑到温度对超声波传播速度的影响,采用DS18B20温度传感器实现温度补偿,实验数据表明,采用温度补偿后提高了测量的精度和稳定性。     

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...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

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...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.