热电偶标定实验的动态演示

提出采用微机数据采集系统改进实验装置,对热电偶标定实验进行动态演示,使学生对标定实验中的温升过程有直观地认识,对热电偶温度与热电势的单值函数关系有更深刻地理解。     

基于平衡点增量模糊控制的水温传感器测控平台设计

针对传统温度模糊控制在逼近稳态的调节过程中,需要经历较长的探寻调整时间这个缺点,提出了基于平衡点增量的温度模糊控制策略。开发了以DSP为核心的发动机水温传感器测控平台,实现了硬件设计、温度标定和基于平衡点增量的模糊控制策略。测试结果表明,温度传感器信号测量准确可靠,模拟温度工况控制快速平稳。该控制策略可适合惯性较大系统的动态控制。该测控平台为实验者进行温度传感器参数测量与标定、调理及驱动电路设计、控制策略验证、仪表技术研究等提供了良好的实验平台。     

热电偶定标实验误差研究

热电偶是一种常用的温度传感器。它是基于热电效应,将热信号转换成电信号进行传递,从而达到远距离测温。热电偶在使用前必须进行定标,确定温差电动势与温度之间的对应关系,确定温差电偶常数α。本文介绍了比较法对热电偶定标的原理及实验结果,并对实验可能产生的误差做出分析。     

测温电路中温度传感器性能的讨论

温度传感器的非统性特性是影响测温精度的主要因素之一，模似式测温仪表如曾大量使用的XCZ动圈仪表，就因非线性特性难以得到校正而影响了精度。采用微机控制测温过程时，必须首先了解温度传感器的工作原理及特性，用软件的方法对非线性进行补偿，才能发挥微机的优势，测量结果就更具有使用价值。下面作者简要就常用测温元件的特性加以讨论，以供设计时参考。1．热电偶热电偶是将两根不同的导体的一端焊接（或粘合）而成，这两根导体称作热电极，其焊接端为热电偶的热端即测量端，非焊接端为冷端或参考端。在进行温度测量时，热电偶的热端…     

用于研究害虫热致死动力学的加热板系统研制

设计了一种加热板系统,包括铝制保温盒、铝制上下底板、上下电加热膜、气体循环通道、T型热电偶温度传感器、PID控制器、变压器、固态继电器和计算机。并通过实验证明了该加热板系统可以用于研究害虫的热致死动力学。     

热电偶的测温误差分析及解决方案

热电偶是一种最简单、最普通的温度传感器。可是如果在使用中不注意,也会引起较大测量误差。针对当前存在的问题,文章详细探讨了影响测量误差的主要因素:装配误差、测量误差、响应响应误差、热辐射及热阻抗误差、劣化误差等,并指出相应的解决方案,对提高测量精度,延长热电偶寿命,有一定帮助。     

热电偶温度传感器冷端补偿和信号线性化

介绍各种热电偶温度传感器的基本工作原理及其信号特点,提出了几种冷端补偿办法,指出了热电偶温度信号线性化规律.     

自制温度传感器的标定与研究

通过加热自制热电偶温度传感器,在各个温度下测量对应的输出电压,从而建立一个关于温度/电压的一元线性数学模型。之后将热电偶放入发动机机油中测量机油温度,调整变量,读取在不同变量下输出的电压,利用先前建立的数学模型得出温度。     

一种新型的硅太阳电池负载特性实验装置的研究

设计制作了太阳电池负载特性测试系统,详细阐述了采用半导体致冷器、温度传感器（热敏电阻、热电偶）制成可调恒温样品台的原理及测试效果。     

热电偶传感器的温度测试

热电偶温度传感器是将被测温度转化为毫伏(mv)级热电动势信号输出.通过连接导线与显示仪表相连接组成测温系统,实现温度自动测量、显示或记录、报警及控制.     

远程校准系统通用环境的分析与设计

在深入计量校准机构进行调查和分析现有远程校准系统的基础上,设计了一种普遍通用的远程校准系统。该校准系统投入较少,适应能力强,能提高校准机构的工作效率,为各企事业单位的器具送检节省了大量的时间。     

工业热电偶自动检定系统

介绍一种热电偶自动检定系统的整体结构、硬件组成、软件设计和主要技术问题的解决方法。该装置满足工业热电偶检定的技术要求．系统测试精度高,软件功能丰富,操作简便,易于普及推广。     

Within and between person associations of calibration and achievement

Self-regulated learning (SRL), the ability to set goals and monitor and control progress toward these goals, is an important part of a positive mathematical disposition. Within SRL, accurate metacognitive monitoring is necessary to drive control processes. Students who display this accuracy are said to be calibrated, and although calibration is a growing area of research within Educational Psychology, unanswered questions remain about calibration's role as an aspect of metacognition, including the unique association between calibration and academic performance. In this study, calibration is characterized as part of a dynamic system that varies across tasks within the same person; variance in calibration is associated with variance in performance gain for the same student across tasks (quizzes within a year-long mathematics curriculum, ST Math). Both accurate determinations of certainty (Sensitivity) and uncertainty (Specificity) have unique small, yet statistically significant, associations with performance gains from pre to posttest in ST Math. For Specificity, there also remains a contextual association with performance at the Person level. Results are discussed in light of prior research on calibration and of theories of SRL; the data and analyses present a novel approach to studying calibration within a dynamic system and offer insights for future work.     

一种用于宽动态范围上的高精度散射测量的标准方法

The co-effect of transmitted power fluctuation and system nonlinearity produce deviations in scatterometer measurement results . An internal calibration method to deal with this problem is proposed. The method can result in more precise scatterometric measurements in a wide range. The basic principle of the method is combining real-transmitted-power detection with the calibration of system nonlinearity. A practical scheme to implement the method is also presented, which is developed based on a special designed mechanism of a microwave radiometer-scatterometer combined system.     

基于特征单应矩阵的双目摄像机系统贪婪标定方法(英文)

在贪婪及直觉的框架下,针对双目摄像机系统提出一种基于平面模板且未考虑光学畸变的线性标定方法.利用单应矩阵的特性及近距离的双目一致性约束进行标定.首先,为计算双摄像机内部几何特性,根据所有模板平面各自的单应矩阵具有特征线的属性,构造具有几何意义的成本函数;采用鲁棒的总误差最小二乘拟合策略,恢复精确的主点坐标.其次,引入像素单元纵横比的先验信息,求取精确的主轴长.然后,精确地获取所有平面模板关于各自相机的外部几何.最后,利用强加于三维几何空间中的一致性约束来计算双目摄像机之间的刚体变换关系.仿真及真实图像实验表明,所提算法能获得较可靠的标定结果,满足精度要求不是很高的应用需求,且对计算机视觉不是很内行的普通用户,能较容易地实现.     

Improvement of Camera Calibration Accuracy Based on Periodic Arrangement Characteristics of Calibration Target Pattern

Conventional camera calibration that employs calibration targets is a commonly used method to acquire a camera's intrinsic and/or extrinsic parameters. The calibration targets are usually designed as periodic arrays of simple high-contrast patterns that provide highly accurate world coordinate system points and the corresponding image pixel coordinate system points. The existing pixel coordinate extraction algorithms can reach a sub-pixel level; however, they treat each single pattern in one image as an independent individual, which makes it difficult to further improve extraction accuracy. In this paper, a novel method is proposed by utilizing the periodic arrangement characteristics of the calibration target pattern as a global constraint to improve the calibration accuracy. Based on a camera's pinhole model, the intersection point of two fitted curves is used as an optimized pixel point to replace the initial one. Following the pixel coordinate optimization procedures, experiments were performed using real data from a 3D laser line scanner and a dynamic precision calibration target. Our results show that the relative errors of camera homography matrix elements obtained by the proposed optimization method were reduced compared with the commonly used method. The average coordinate measurement accuracy can be improved by nearly 0.05 mm. It is shown that the proposed optimization method can enhance the camera calibration accuracy,especially when the extracted pixels are of poorer precision.     

A long-term in situ calibration system for chemistry analysis of seawater

An in situ calibration system is a versatile exploration instrument for electrochemical sensors investigating the biochemical properties of the marine environment. The purpose of this paper is to describe the design of an auto-calibrating system for electrochemical （pH） sensors, which permits two-point in situ calibration, suitable for long-term measurement in deep sea aqueous environments. Holding multiple sensors, the instrument is designed to perform long-term measurements and in situ calibrations at abyssal depth （up to 4000 m）. The instrument is composed of a compact fluid control system which is pressure-equilibrated and designed for deep-sea operation. In situ calibration capability plays a key role in the quality and reproducibility of the data. This paper focuses on methods for extending the lifetime of the instrument, considering the fluidics design, mechanical design, and low-power consumption of the electronics controller. The instrument can last 46 d under normal operating conditions, fulfilling the need for long-term operation. Data concerning pH measured during the KNOX18RR cruise （Mid-Atlantic Ridge, July-August, 2008） illustrate the desirable properties of the instrument. Combined with different electrodes （pH, H2, H2S, etc.）, it should be of great utility for the study of deep ocean environments, including water column and diffuse-flow hydrothermal fluids.     

Flexible Calibration Method for 3D Laser Scanner System简

In this paper, a flexible high-precision calibration method suitable for industrial field was proposed. The complexity of the coordinate transformation was simplified by choosing the camera coordinate system as the unified reference coordinate system. A flexible planar calibration pattern was introduced to the calibration process, which can be arbitrarily placed and from which the known feature points can be extracted to construct other unknown feature points. With the known intrinsic parameters, the laser projector plane equation was fitted by the multi-noncollinear points, which were acquired through the principle of triangulation and the projective invariance of cross ratio. With this method, the strict alignment and multiple times of coordinate transformation can be avoided. Experimental results showed that the arithmetic mean of the root mean square （RMS） error of distance was 0.000 7 mm.     

融合超声传感与视觉图像的智能小车避障设计

基于MATLAB 软件及Arduino 开发板等硬件,提出并设计了一种融合超声传感和视觉图像技术并能实现主动避障的智能小车。建立单目相机的数学模型,并使用MATLAB 的相机标定工具箱进行参数标定,根据标定结果对图像畸变进行校正并实现了障碍物目标的跟踪测距。而后通过MATLAB软件及Arduino 开发板调用超声波模块实现对前方障碍物的测距。根据系统结构方案选用合适的硬件搭建智能小车,测试表明,该车能满足不同场景下实现主动避障,为智能驾驶系统设计提供参考。     

自由曲面非接触测量技术的研究(英文)

提出了一种基于坐标测量机、测头回转体和激光三角法测头的非接触三维测量系统 ,并介绍了测量系统的工作原理 .同时给出了采用标准球对测量系统进行标定的方法 ,建立了测量系统的数学模型 ,还对白纸样板曲面进行了实际测量