Method of Predicting Water Content in Crude Oil Based on Measuring Range Automatic Switching

Water content in output crude oil is hard to measure precisely because of wide range of dielectric coefficient of crude oil caused by injected dehydrating and demulsifying agents.The method to reduce measurement error of water content in crude oil proposed in this paper is based on switching measuring ranges of on-line water content analyzer automatically.Measuring precision on data collected from oil field and analyzed by in-field operators can be impressively improved by using back propogation （BP） neural network to predict water content in output crude oil.Application results show that the difficulty in accurately measuring water-oil content ratio can be solved effectively through this combination of on-line measuring range automatic switching and real time prediction,as this method has been tested repeatedly on-site in oil fields with satisfactory prediction results.

A novel wide-range precision instrument for measuring three-dimensional surface topography

We developed a measuring instrument that had wide range, high precision, small measuring touch force. The instrument for three-dimensional (3D) surface topography measurement was composed of a high precision displacement sensor based on the Michelson interference principle, a 3D platform based on vertical scanning, a measuring and control circuit, and an industrial control computer. It was a closed loop control system, which changed the traditional moving stylus scanning style into a moving platform scanning style. When the workpiece was measured, the lever of the displacement sensor returned to the balanced position in every sample interval according to the zero offset of the displacement sensor. The non-linear error caused by the rotation of the lever was, therefore, very small even if the measuring range was wide. The instrument can measure the roughness and the profile size of a curved surface.

STUDY ON THE SCANNING PROBE MICROSCOPE WITH WIDE MEASURING RANGE

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Advancement in Wide Area Monitoring Protection and Control Using PMU’s Model in MATLAB/SIMULINK

A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station.

Recent Development of Dielectric Elastomer Transducers and Potential Applications

Power generation using dielectric elastomer transducers is cheap, light, stackable, easy to install, and highly efficient. Also, since the dielectric elastomer transducer is an actuator developed into an artificial muscle, if the DE motor is further developed, it might be possibly be able to drive a vehicle. Efficient robot driving, various industrial machines and the use of dielectric elastomer sensors to optimize the driving may also help solve the above problems from the perspective of eco-driving. This paper describes the latest level of development of dielectric elastomers, their main problems and solutions to these problems, and their potential applications. The possibilities and concrete plans for building local global smart cities (including local generation power for local consumption), efficient transportation, and environmental monitoring systems utilizing dielectric elastomers are also discussed.

宽基线立体视觉远距离目标位姿测量

立体视觉测量作为被动探测技术的一种,广泛应用于位姿测量领域。针对传统立体视觉在远距离环境下目标位姿测量受限的问题,提出一种宽基线立体视觉远距离目标位姿测量方法。基于三点定面测量原理,构建位姿测量数学模型,采用相机参数解耦策略,对测量系统所需参数进行标定。设计远距离场景下易于识别的合作目标,利用两台相机对目标进行成像,通过计算合作目标中心点的三维空间坐标,完成远距离环境下目标位姿的解算。实验结果表明,在75~85 m距离下,该方法对目标间相对位姿测量精度优于0.5%,X和Y方向均方根误差优于7.3 mm,Z方向均方根误差优于22.6 mm,可有效适用于远距离下的目标位姿测量应用。

高速铁路牵引变电所智能化建设方案研究

智能牵引变电所是智能牵引供电系统的核心,由智能化一次系统、广域保护测控系统和智能辅助系统构成。为提高目前在建高铁牵引供电系统智能化水平,探讨并提出了针对其牵引变电所的智能化改造方案。

用于智能量测开关的超宽输入DC-DC模块研究

为了解决智能量测开关内部自取电电流互感器输出电压变化大的问题,需要在后级级联具有超宽输入电压范围的DC-DC模块来产生稳定的系统供电电压。研究了一种基于恒定开通时间控制和断续模式非同步Buck电路的超宽输入DC-DC模块。根据输入电压和输出电压的差距大小,采用变频和准定频分段控制方式。实现大压差功率变换的同时,该DC-DC模块还具有极快的动态响应。利用PSIM软件对DC-DC模块电路的特性进行仿真分析和验证。研制了一台功率为5 W的硬件样机进行测试,给出了部分关键实验波形。实验结果表明,该DC-DC模块具有输入范围超宽、动态响应极快和稳定性高的特点。

Wide measurement range and high sensitivity spongy MWCNT/polydimethylsiloxane pressure sensor based on a single-electrode enhanced triboelectric nanogenerator

Flexible pressure sensors have broad application prospects,such as human motion monitoring and personalized recognition.However,their applicability is limited by complex structures,low output performance,low sensitivity,and narrow measurement range.In this study,we report a single-electrode spongy triboelectric sensor(SSTS)mainly composed of spongy composite multi-walled carbon nanotubes/polydimethylsiloxane(MWCNT/PDMS)film and conductive fabric,which can simultaneously generate contact electrification and electrostatic induction coupling in a single-electrode contact-separation mode.The SSTS combines the triboelectric effect,properties of doping material,and spongy porous structure(soft sugar as a sacrificial template).An SSTS with an MWCNT content of 10 wt%and a porosity of 64%exhibits high sensitivity,a wide measurement range,and excellent linearity.It also displays two sensitivity regions(slopes):1.324 V/kPa from 1.5 to 28 kPa in the low-pressure range and 0.096 V/kPa from 28 to 316.5 kPa in the high-pressure range,with linearities of 0.980 and 0.979,respectively.Furthermore,the SSTS delivers a high-performance output and high stability,thus enhancing the monitoring of hand pressure changes,human movement,personalized spatial recognition,and other detection tasks.This new strategy for human motion monitoring shows great potential in the healthcare fields,sports rehabilitation,and human-computer interactions.

基于双目近景图像的车体相对车位方位视觉检测方法

为了提高自动泊车领域单一应用机器视觉技术对目标空车位方位检测的适应性,研究了一种基于双鱼眼镜头近景图像的车体相对车位方位机器视觉检测方法.采用双鱼眼镜头采集车位近景图像,通过对图像校正、图像拼接、逆透视变换和图像二值化等图像处理,提取俯视平面上目标空车位线轮廓边缘和双鱼眼镜头位置点.建立车体相对目标空车位的坐标系,通过视觉识别和像素点坐标计算确定双鱼眼镜头在车位二维坐标系下的坐标.基于已知车位和车体尺寸、鱼眼镜头在车体上安放位置等信息,运用几何方法建立车体相对车位方位角与距离的计算关系模型.结果表明:方位角检测最大相对误差为9.16%,距离检测最大相对误差为3.89%,提高了目标空车位检测的适应性.

曝光一定时单相机辐射测温范围的影响因素分析

针对单相机单波长测温和比色测温过程中测温范围较窄的问题,以单波长测温过程为基础,推导了相机传感器动态范围和工作波长对单相机测温范围影响的理论公式,并对波段选取过程中的影响因素进行了分析。理论分析结果表明:相机动态范围和波长的选取限制了一次曝光时测温范围的最大跨度值,在相机传感器唯一确定时,相机动态范围一定,根据波段选取原则选定工作波段,选定估计温度范围下限之后,由公式即可确定待测温度上限,再根据实际测温范围调整波段和估计测温下限;配合调节曝光及光圈,充分利用相机传感器的全动态范围,可实现单相机辐射测温法中宽温度范围的测量。此外,通过涡流加热实验和熔池温度场测量实验对上述影响因素进行验证,选取更优波长和更优曝光时间,可提高单次测温跨度至少40%,为单相机测温技术的具体实施提供技术参考。

超高真空计微弱离子流检测技术研究

在超高真空环境下,Bayard-Alpert型电离真空计通过电离气体分子得到的离子流信号十分微弱,且极易受到干扰。介绍了一种用于超高真空测量的微弱信号检测系统,包括测量电路、调零电路与处理模块。该系统采用高精度放大器与高绝缘继电器,可以实现微弱信号的精密放大,满足mA级至亚pA级范围的宽量程电流信号检测;能够自动完成测量档位的切换、系统调零、数据处理与真空全压力值计算,测量下限可达10-13A量级,可用于超高真空计离子流的精确测量,具有良好的线性及稳定性。

MC-LRF based pose measurement system for shipborne aircraft automatic landing

Due to the portability and anti-interference ability,vision-based shipborne aircraft automatic landing systems have attracted the attention of researchers.In this paper,a Monocular Camera and Laser Range Finder(MC-LRF)-based pose measurement system is designed for shipborne aircraft automatic landing.First,the system represents the target ship using a set of sparse landmarks,and a two-stage model is adopted to detect landmarks on the target ship.The rough 6D pose is measured by solving a Perspective-n-Point problem.Then,once the rough pose is measured,a region-based pose refinement is used to continuously track the 6D pose in the subsequent image sequences.To address the low accuracy of monocular pose measurement in the depth direction,the designed system adopts a laser range finder to obtain an accurate range value.The measured rough pose is iteratively optimized using the accurate range measurement.Experimental results on synthetic and real images show that the system achieves robust and precise pose measurement of the target ship during automatic landing.The measurement means error is within 0.4in rotation,and 0.2%in translation,meeting the requirements for automatic fixed-wing aircraft landing.

宽量程比差压流量计的研究

标准差压流量计一般存在量程比不够宽的缺点,为弥补不足,采用更换孔板法、多套流量计测量法、多台差压式流量计切换使用法、数字通信传输法等方法来扩大量程比。讨论了量程过范围对差压变送器性能的影响和过范围试验方法,以及计量检定和流量测量准确度现场验证问题。分析表明,差压式流量计的安装方式也是保证测量准确度和量程比的重要环节,必须严格执行相应的规程,避免引起差压信号的传递失真,进而引起误差。

基于单GM计数管的宽量程γ监测仪研究

以单GM计数管宽量程探测技术实用化为目的,介绍了单GM计数管宽量程探测技术原理,开发了宽量程探测模块,并基于该探测模块设计了宽量程γ监测仪硬件与软件。对所研制的工程样机进行了实验测试,包括剂量率测试、累积剂量测试及过载测试等。实验结果表明:基于国产J305低量程计数管研制的工程样机测量范围至少包括本底至10 Gy·h-1共8个量级,整个测量范围内固有相对偏差小于7%;当剂量率高于5μGy·h-1时,变异系数小于7%;累积剂量测量相对偏差仅为0.2%;采用大剂量率照射未出现过载现象。基于单GM计数管的宽量程γ监测仪符合剂量监测设备测量要求,可应用于从本底到核事故大范围的γ剂量率监测,在核电行业和辐照站等涉核单位有广阔的应用前景。

超大钢管桩非接触式圆周测量技术应用研究

文章介绍了一种超大钢管桩非接触式圆周自动测量技术及其设备的研制,该设备能够快速精确地测量超大钢管桩内壁周长及其长短轴、偏移角度等参数。其利用伺服电机带动激光测距仪旋转,测量到不同旋转角度下传感器到钢管桩内壁的距离后,通过最小二乘法对数据进行椭圆拟合,从而得到钢管桩内壁椭圆方程,达到快速计算圆周周长的目的。测试结果表明,该设备显著提高了超大钢管桩生产过程中圆周测量的精度、自动化程度,为钢管桩生产提供了可量化的质量标准,极大提高了产品质量与生产效率。

基于顺序注射技术的量程自动切换总磷在线监测方法

针对地表I~V类水总磷准确快速测定的需求及总磷水质自动分析仪的技术要求,文中结合顺序注射技术和钼酸铵分光光度法,基于地表水国家检测标准,以水质总磷参数为检测对象,设计一种小型微量原位水质检测仪。该系统主要通过自主设计的消解池结构来达到快速消解、检测的目的。由于在实际水样与行业标准中,总磷含量标准限值分别为0~2 mg·L^(-1)和0~50 mg·L^(-1),故自主设计检测程序,根据检测信号值进行判断,自动调整进液量,设计一种量程可自动切换的在线检测系统,实现30 min内针对不同量程范围的总磷自动检测。实验结果表明:总磷测定量程为0~2 mg·L^(-1)时,校正决定系数为R2=0.995 4;重复性的相对标准偏差RSD为1.32%~2.24%;实际水样相对误差为1.63%~3.31%;当量程为0~50 mg·L^(-1)时,系统重复性误差为3.61%,零点漂移为2.04%,量程漂移为3.39%,直线性为4.33%。所设计系统具有良好的稳定性和可靠性,成本低、功耗低、所需试剂少、体积小,更适用于目前总磷在线监测需求。

发电机冷却介质品质仪的开发

发电机冷却介质品质仪是一种实现了氢气纯度、氢中氧、压力、湿度在压换算、测量自动流量控制的多功能集成式实验室仪表。在当前的工业技术业态中,传统电厂的散热控制、测算控制还有着较大的提升空间,特别是在新能源、健康能源方面,有着巨大的改善需要。因此发电机冷却介质品质仪作为一种电力系统自动化所配套的设施有较大的实用空间,冷却介质系统兼具功效性与环保性,是我国“十四五”期间需要大力发展的工业科学技术。

动态下红外热释电传感器的目标定位方法

为了提高热释电传感器的探测灵敏度,拓宽其传统使用范围,提出了一种动态下热释电传感器发现人体目标并测向测距的新型使用方法。该方法大大扩展了热释电传感器的探测范围,根据波形能准确判定目标的方向,利用经验值推断出人体的目标距离。该系统采用热释电红外传感器作为探测器,创新运用红外透镜代替传统用法中的菲涅耳透镜,在步进电机的匀速带动下,单片机记录测量区域的原始红外波形(在环境基本不变且没有目标进入的情况下,波形具有一定规律且基本保持不变);目标进入测量区域内时将引起原始规律变化,单片机利用帧间差分法求出变化的波形,判断目标有无及方向、距离等结果。与热释电传感器的传统使用方法相比,该方法具有反应迅速、探测灵敏、探测范围大、可测向测距等新特点,大大拓宽了热释电传感器的使用范围,进一步提升了其在安防和智能家居系统中的应用。

基于巨磁阻效应的高性能电流传感器及其在智能电网的量测应用

智能电网需要先进传感测量技术的支持。为此,针对智能电网中的电流测量需求,介绍了基于巨磁阻效应的高性能电流传感器,包括传感器系统结构、磁环、巨磁阻传感芯片、信号处理电路等的设计,以及对温度稳定性、电磁兼容性的设计。实验结果表明,所设计的基于巨磁阻效应的高性能电流传感器在对电网中暂态电流、直流电流、泄漏电流、电晕电流的测量中表现出良好的性能,实现了对带宽直流到10 MHz、幅值1 m A至1.6 k A的电流的精确测量。相比其他电流测量装置,基于巨磁阻效应的高性能电流传感器具有体积小、灵敏度高、成本低、测量范围大、可集成度高等综合优势,适应了智能电网的测量需求。最后,提出了后续研究方向。