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In-situ Auto-analysis System of Seawater Nutrients

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In-situ Auto-analysis System of Seawater Nutrients

第三届国际仪器科学技术学术研讨会

作者： WANG Yan WANG Zhi-li HAN Yong-hui state key {2. of precision measuring technology & instruments tianjin university tianjin 300072 china

For prediction of red tide and knowledge of the nutrients’ concentrations and their change trend, based on the principle of absorbance, an auto analysis system of seawater nutrients is designed, which

关键词： PROFIBUS-DP bus MCGS seawater nutrients in-situ monitor

measuring System for Micro Force Based on Electrostatic Theory

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Measuring System for Micro Force Based on Electrostatic Theo...

2.09 9th International Conference on Electronic Measurement & instruments（ICEMI’2.09）

作者： Yongyue Qi Haitao Wang Yuchi Lin Meirong Zhao (state key {2. of precision measuring technology and instruments, tianjin university, 300072 tianjin, china )

The micro force measuring technology is widely used in the area of micro friction test, liquid surface tension analysis, organism micro-structure force test, measurement and calibration of MEMS and NEMS, etc. In view of measurement and realization approach of micro force value, a micro measuring system is proposed. A control electrostatic force generator is adopted to reproduce micro force. The basic working principle is an exact designed cylindrical capacitor with the characteristics of long measurement range, fine linearity and faint border effect. A linear axletree with high precision and linearity is used to ensure concentricity of movement. In order to eliminate the interference from parasitical capacitance a hermetical shield is designed. By means of measuring the voltage between electrodes and capacitance change gradient, the micro force test at NN degree could be realized.

关键词： micro force value capacitance change gradient electrostatic force capacitive sensor

Mining subsidence control by solid backfilling under buildings

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中国有色金属学会会刊：英文版 2011年第S3期21卷 670-674页

作者： ZHA Jian-feng1, 2. 3, GUO Guang-li1, 2. FENG Wen-kai3, WANG Qiang1, 2.1. key laboratory for Land Environment and Disaster Monitoring of the {2. Bureau of Surveying and Mapping, china university of Mining and technology, Xuzhou 2.1116, china 2. Jiangsu key laboratory of Resources and Environmental Information Engineering, china university of Mining and technology, Xuzhou 2.1116, china 3. {2. key laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of technology, Chengdu 610059, china key laboratory for Land Environment and Disaster Monitoring of the {2. Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu key laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China state key {2. of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

关键词： solid backfilling mining subsidence control mining under buildings

Research on Measurement of Lens Centering Errors Based on Image Processing

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Research on Measurement of Lens Centering Errors Based on Im...

2.07亚洲光电子会议光学设计与测试分会场

作者： Yuchi Lin Guimei Dong* Yinguo Huang Yijie Niu state key {2. of precision measuring technology and instruments tianjin university tianjin 300072 china

To combine modern sensor technology with digital image processing, a real-time measurement system of lens centering errors is designed based on CCD sensor. Following transmission principle as well as reflection principle, a scheme that applies two orthogonal light sources to the measurement system is put forward with the combination of cross and double slit reticles. The experimental result shows that the standard deviation of centering errors is up to 0.0019mm, the limit errors is ±0.0057mm. It is proved that the measurement system is of good reliability and practicability for measurement of centering errors. In addition, the designed system is suitable for multi-parameter measurement, including focal length, intercept and curvature radius, etc.

关键词： centering errors transmission measurement reflection measurement collimator digital image processing

基于动态压力信号的管道泄漏特征提取方法研究

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石油学报 2010年第2期31卷 338-342页

作者：张宇靳世久何静菁陈世利李健天津大学精密测试技术与仪器国家重点试验室天津300072

动态压力变送器能直接测量管道压力的动态变化,因而比基于普通压力变送器的管道泄漏检测具有更高的灵敏度。研制了一种应用于长输油气管道泄漏检测的动态压力变送器,并介绍了其结构组成和工作原理。用动态压力变送器获取了管道的动态压... 详细信息

动态压力变送器能直接测量管道压力的动态变化,因而比基于普通压力变送器的管道泄漏检测具有更高的灵敏度。研制了一种应用于长输油气管道泄漏检测的动态压力变送器,并介绍了其结构组成和工作原理。用动态压力变送器获取了管道的动态压力信号,利用经验模态分解的方法将信号分解为多个固有模态函数(IMF)之和,选择主要的IMF分量进行归一化峭度分析,从而提取信号的特征向量。现场应用实例表明,该方法能够有效地对管道泄漏和调泵调阀等事件进行特征信号提取。

关键词：管道泄漏检测动态压力变送器动态压力信号特征向量提取经验模态分解

基于比例重复控制的MMC-SST子模块电容纹波电压抑制策略

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电力系统保护与控制 2024年第15期52卷 46-57页

作者：王要强贾显益赖锦木陈天锦吕忠涛梁军郑州大学电气与信息工程学院河南郑州450001 河南省电力电子与电力系统工程技术研究中心河南郑州450001 许继电源有限公司河南许昌461000 河南省智能充电技术重点实验室河南许昌461000 国网呼伦贝尔供电公司内蒙古呼伦贝尔021000 卡迪夫大学工程学院英国卡迪夫CF243AA

基于模块化多电平变换器的固态变压器(modular multilevel converter based solid state transformer,MMC-SST)是实现交直流混合配电网柔性互联及能量多向流动的关键装备。针对固态变压器输入级MMC子模块电容纹波电压过大,导致装置的体... 详细信息

基于模块化多电平变换器的固态变压器(modular multilevel converter based solid state transformer,MMC-SST)是实现交直流混合配电网柔性互联及能量多向流动的关键装备。针对固态变压器输入级MMC子模块电容纹波电压过大,导致装置的体积和成本增加的问题,提出一种基于比例重复控制的MMC-SST改进纹波电压抑制策略。首先利用基于比例重复控制的电容电压闭环得到调整后的功率移相角。然后,通过双有源桥变换器将子模块电容纹波功率传递到低压直流母线,从而有效抑制MMC子模块的各频次纹波电压,达到减小电容值的目的。最后,仿真结果表明在网侧电压对称或不对称工况下,基于比例重复控制的MMC-SST子模块电容纹波电压抑制策略均具有良好的纹波电压抑制能力。

关键词：固态变压器模块化多电平变换器电容纹波抑制波动功率传递比例重复控制桥臂电流控制

维普期刊数据库博看期刊

A simulation of citrus oil adsorption separation in the supercritical carbon dioxide

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化工进展 2011年第S2期30卷 36-40页

作者： HU Zhihui,ZHANG Donghui,WANG Jixiao (Chemical Engineering Research Center,state key {2. of chemical engineering,School of Chemical Engineering and technology,tianjin university,tianjin 300072,china)

Aspen Adsim was used to simulate the fractionation of citrus oil with extraction and adsorption combined method in supercritical carbon *** dynamic behavior in a isothemal and adiabatic bed could be described succesfully,and the simulation results agreed with the experimental *** effect of adsorption time,the flow rate of feed on the concentration of components in product and the recovery were *** amount of loading composition on the adsorbents changed with adsorption time and axial distance of bed was also investigated.

关键词： Supercritical fluid adsorption carbon dioxide citrus oil Aspen Adsim

Development of an integrated model system to simulate transport and fate of oil spills in seas

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Science china(Technological Sciences) 2010年第11期53卷 2423-2434页

作者： WANG JinHua & SHEN YongMing state key {2. of Coastal and Offshore Engineering,Dalian university of technology,Dalian 11602.,china state key {2. of Coastal and Offshore Engineering Dalian University of Technology Dalian China

A three-dimensional integrated model is developed for simulating transport and final fate of oil spills in *** model contains two main modules,flow and transport-fate *** flow module uses an unstructured finite-volume wave-ocean coupling *** unstructured meshes provides great flexibility for modeling the flow in complex geometries of tidal creeks,barriers and *** the transport-fate module the oil dispersion is solved using a particle-tracking *** diffusion is simulated using random walk techniques in a Monte Carlo framework,whereas the vertical diffusion process is solved on the basis of the Langeven *** model simulates the most significant processes that affect the motion of oil particles,such as advection,surface spreading,evaporation,dissolution,emulsification and turbulent diffusion as well as the interaction of the oil particles with the shoreline,sedimentation and the temporal variations of oil viscosity,density and surface *** model simulates either continuous or instantaneous oil spills,and also other toxic *** model has been applied to simulate the oil spill accident in the Bohai *** comparison with the observations,the numerical results indicate that the model is reasonably accurate.

关键词： oil-spill modeling finite-volume method oil particles 3-D unstructured grid

A Novel Method of Multi-range Models by Near-Infrared Spectral Analysis for Components of Organic Materials

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A Novel Method of Multi-range Models by Near-Infrared Spectr...

第三届国际仪器科学技术学术研讨会

作者： ZHANG Xue-dian CHANG Min XU Ke-xin state key {2. of precision measuring technology and instruments tianjin university tianjin 300072 china

Near-infrared (NIR) spectroscopy has gained wide spread acceptance in recent years as a powerful diagnostic tool, particularly for the concentrations of Components of Organic Materials. Frequently, a

关键词： Near-infrared (NIR) PLS non-linear model