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基于SSM框架的大坝监测数据管理系统设计 总被引:1,自引:0,他引:1
针对目前大坝安全监测存在数据不能实时计算分析、展示,长期运行产生的大量数据主要靠人工整编且易出错等问题,结合现代信息化技术手段,以Java作为服务开发语言,设计了基于Spring+SpringMVC+Mybatis(SSM)框架的大坝安全监测数据管理平台,用于大坝监测数据的管理和分析,实现数据采集、存储、查询、计算分析、绘图、生成报表报告、实时监控及远程展示等功能,同时亦为监测仪器管理提供了可视化界面,方便仪器管理。结果表明,基于SSM框架的大坝安全监测数据管理系统实时反馈效果好,操作便捷,数据存取性能好、可视化程度高,便于大坝监测数据的管理与实时分析,为大坝安全运行与决策提供支撑。 相似文献
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设计了一种基于可调谐半导体激光吸收光谱技术的甲烷(CH4)气体监测装置,该装置具有温度监测范围大、监测精度高和实时监测的优点。监测装置的激光光源为波长1650 nm的反馈式激光器,应用波长调谐与锁相放大器技术,对周围环境进行温度补偿与背景扣除,可以较准确地测量周围环境中CH4的体积分数。实验表明,当CH4体积分数小于1%时,该装置的监测精度为±0.02%;当CH4体积分数大于1%时,装置监测误差小于±0.8%,实时监测的最长响应时间为10 s。装置的温度范围为0~40℃,可满足大多数工业生产中对CH4等气体体积分数的监测需求。 相似文献
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为了减少综放面工作人员劳动强度、增加采出率,研究了煤矿采煤机控制系统,分析了煤矿采煤机基本结构,主要包括电气系统、牵引传动部件、截割部件和其他辅助装置,提出了采煤机控制方案和流程,系统主要包括地面监控系统、巷道监控系统与采煤机机载监控系统,并研究了各系统的软件和硬件及关键技术。研究为煤矿采煤机的智能控制提供了参考。 相似文献
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Real‐time monitoring by proton relaxometry of radical polymerization reactions of acrylamide in aqueous solution 下载免费PDF全文
Elton Jorge da Rocha Rodrigues Roberto Pinto Cucinelli Neto Pedro José Oliveira Sebastião Maria Inês Bruno Tavares 《Polymer International》2018,67(6):675-683
The potential of time‐domain nuclear magnetic resonance (TD‐NMR) for the real‐time monitoring of solution radical polymerizations is demonstrated. A model system composed of a redox‐pair initiator system, acrylamide as monomer and water as solvent was investigated. A second‐generation continuous wave free precession technique was employed to measure the longitudinal relaxation time constant (T1) of the samples throughout the polymerization reactions. This parameter was shown to be sensitive to the reactant feed free‐radical enhancement of the water molecule relaxation time, making it a good probe to monitor monomer conversion in real time in an automated, non‐destructive fashion. It was found that the T1 value was better than the transverse relaxation time constant (T2) for describing the evolution of the polymerization reactions, due to its greater sensitivity to paramagnetic effects. The TD‐NMR signal variation observed was linked to the formation, propagation and termination steps of the radical polymerization kinetics scheme. These first results may contribute to the application of real‐time monitoring of radical polymerization reactions employing low‐cost and robust TD‐NMR spectrometers. © 2018 Society of Chemical Industry 相似文献
28.
This study presents a back-analysis of geotechnical parameters on prefabricated vertical drain improved ground at a site in the Mekong Delta. Various time?settlement behaviors that reflected different clay thicknesses and loading patterns were observed. The total surface settlement behavior at several monitoring locations was simulated using an updated exponential method that considered staged construction. The analyzed results were validated by substituting the values into a theoretical solution for radial consolidation. The estimated theoretical behaviors were comparable with the monitored behaviors. The geotechnical parameters were back-analyzed by applying the previously analyzed results to various theoretical and empirical formulas. However, the use of extensometer data that were installed at large intervals produced different values of the geotechnical properties. Furthermore, finite element analysis supported the back-analyzed total settlement behaviors and nearly disregarded the application of the geotechnical properties that were obtained using either surface or subsurface settlement data. However, settlements and excess pore pressures in the sublayers were not successfully predicted even when the geotechnical properties were adjusted. Thus, subsurface instruments that can be installed closely in thick clay deposits are required to reliably reevaluate the variations in geotechnical properties along a certain depth. 相似文献
29.
We propose an in-process height measurement system for a weld bead and feedback control system for wire-feeding speed for high-quality laser deposition. Metal additive manufacturing, especially laser metal-wire deposition, is effective for complex shape fabrication and repair processing. However, we must control the gap between a weld bead and a feed wire in an optimal range for high-quality deposition. Conventionally, the Z-stage pitch for multi-layer deposition must be precisely adjusted by each deposition shape. In this paper, we design an in-process height measurement system that is integrated in a laser processing head, which measures the weld bead height by a line section method. We decreased the influence of the intense thermal radiation generated from a melt pool by inserting the band-pass filter of the line beam's wavelength in the imaging system and optimizing its line laser power. Consequently, our system can measure the weld bead height near the melt pool, which is 4 mm in front of it. Next we show that our proposed system can measure the weld bead height during wire-laser metal deposition with 50-μm accuracy by comparing its value to the true value. Finally, we achieved a cylinder shape deposition of 50-mm height, regardless of the Z-stage pitch and the cylinder diameter of the multi-layer deposition, by controlling the wire-feeding speed based on the measured weld bead height. 相似文献
30.
针对煤矿发生事故后传统救援监控系统无法实时对井下人员进行动态定位,导致矿井救援盲目性大、救援效率差、救援难度大等技术难题,为了进一步提高煤矿救援效率,通过技术研究,设计了一套以通信基站为核心的智能化救援监控系统,分析了该系统结构组成、工作原理,通过在担水沟煤矿井下实际应用效果来看,智能化救援监控系统对人员定位精准度达95%,实现人员动态位置三维成像,救援效率提高至80%以上,有效缩短了煤矿事故救援时间,取得了显著应用成效。 相似文献