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为提高基坑开挖过程中变形监测实时预测的准确性与可靠性,文章结合灰色系统理论,考虑关于监测数据与基坑开挖深度之间的关系,建立离散灰色系统模型,利用该模型对原始沉降数据进行分析预测,并通过实验数据对比分析得出,利用离散灰色系统模型预测的结果与实测数据相吻合,预测精度可靠,且具有一定的参考价值。 相似文献
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《工程建设》2020,(2)
准确的深基坑变形预测和控制是当前地下工程监控测量研究领域的热点问题,尤其是深基坑变形的中长期预测,对保障现场人员和财产安全具有重要的预警作用。以某地铁盾构始发竖井深基坑为工程背景,采用滑动平均法(MA)对基坑变形现场实测的地表沉降原始数据进行去噪处理,增加监测数据的权重,然后引入灰色Verhulst模型对去噪后的数据进行中长期拟合预测,最后对比分析灰色GM(1,1)模型、灰色Verhulst模型、滑动平均-灰色Verhulst模型的预测精度。结果表明:滑动平均-灰色Verhulst模型的预测精度较高,适用于基坑中长期变形预测。该结果可为提高类似变形问题的预测精度提供启示作用。 相似文献
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基坑变形灰色预测预警系统 总被引:15,自引:0,他引:15
文章从分析基坑位移影响因素和位移特征入手 ,提出了根据现场位移观测值建立灰色预测预警模型的思路 ,并讨论了建模过程。实践证明基坑变形灰色预测系统有较好的精度 ,对指导基坑开挖和支护有积极意义 相似文献
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地铁基坑水平位移预测分析 总被引:1,自引:0,他引:1
以某地铁基坑的实测资料为基础,采用灰色系统理论对其水平位移进行了灰色预测.分析结果表明:模型预测值偏大,但其预测结果同样具有较好的精度,并有一定的安全余地.因模型前期预测时序数列是不断更新的,故该模型不能作中长期位移预测. 相似文献
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Bai Wenping 《中国稀土信息(英文版)》2014,(12)
<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH 相似文献
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《中国稀土信息(英文版)》2014,(9)
正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to 相似文献
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《中国稀土信息(英文版)》2014,(10)
<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why 相似文献
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《中国稀土信息(英文版)》2014,(8)
正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets. 相似文献
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<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel 相似文献
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《中国稀土信息(英文版)》2014,(12)
正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow. 相似文献
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分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求. 相似文献
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<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth 相似文献
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《中国稀土信息(英文版)》2014,(6)
正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products 相似文献
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