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地震采集中检波器自然频率的试验分析 总被引:9,自引:1,他引:8
王增明 《石油地球物理勘探》2003,38(3):308-316
为了达到提高分辨率的目的,对不同自然频率的检波器进行了多次试验。通过试验分析认为,检波器在自然频率方面有所差别,在单炮记录上表现为对低、高频干扰压制情况有所不同,但是资料通过处理后,几种检波器的频谱和能量均无明显的差别。高分辨率勘探不等于高频勘探,而是一种宽频带的勘探,所以选择自然频率低的检波器有利于高分辨率勘探。 相似文献
13.
C. Llopis F. Revents L. Batet C. Pretel I. Sol 《Nuclear Engineering and Design》2007,237(18):2014-2023
The Technical University of Catalonia (UPC) has been jointly working with the Asociación Nuclear Ascó-Vandellòs (ANAV) for a number of years in order to establish, qualify and use best estimate (BE) models for the reactors under the control of ANAV. ANAV is the consortium that is responsible for operation of the Ascó and Vandellòs-II reactors. The reactors are Westinghouse-design three-loop PWRs with an approximate electrical power of 1000 MW. The existing integral plant models for each plant are currently used for many different purposes among which are support of plant operation and control. Quite a number of studies have been done in order to improve both safety and plant competitiveness. Most of these dynamic analyses were carried out in relation to transients starting at nominal full power or at least, very close to full power. This paper develops a specific use of the Vandellòs-II plant model for operation and control support at low power involving new ranges of system actuation parameters. It also examines scenarios that are somewhat different from those typically analysed. The study starts showing the results of an assessment case, which is a start-up test and provides some additional qualification, and subsequently attempts to establish calculations to support both an improvement in feed water controls and to set up operating recommendations for low-load manual operation of feed water turbo-pump. Both results hopefully, will produce an outcome, which leads to an improvement in safety and reduces reactor trip probability. 相似文献
14.
M.M.M. El Telbany M.R. Mokhtarzadeh-Dehghan A.J. Reynolds 《Building and Environment》1985,20(1):25-32
This paper extends an earlier report of measurements and computer predictions of flows in a cubical cavity exposed on one side to the scavenging effect of an external stream. Further measurements and photographs are presented; they are consistent with each other and with the predictions of the computational model. Specifically, comparisons are made between measured and predicted mean velocities and turbulent shear stresses, and photographs are used to elucidate features of the shear layers generated by accelerating and decelerating external flows. The computer model is used to deduce approximate relations between internal turbulent activity (measured by mean velocity, turbulence energy and shear stress) and external velocity, percentage ‘window’ opening and relative position of the plane walls upstream and downstream of the cavity. 相似文献
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通过对福建省内高中信息技术相关课程及福建省内外《大学信息技术基础》课程设置的调研,针对当前《大学信息技术基础》教学过程中存在的一些问题,结合自己的工作实际,提出改革教学方式、方法,更新教学内容等,提高计算机基础教学质量和教学效果,以适应创新型、应用型人才培养的社会迫切需要。 相似文献
16.
实验室安全管理是理工类高等院校安全工作的重点内容.针对理工类高校实验室安全管理问题。对理工类高校实验室安全管理的特点和影响实验室安全管理的主要因素进行详细的研究和分析,并以此为基础从实验室安全管理组织体系、监督体系和保障体系三个方面提出建设理工类高等院校实验室安全管理体系的具体措施。 相似文献
17.
Cagdas Hakan Aladag Ufuk Yolcu Erol Egrioglu Ali Z. Dalar 《Applied Soft Computing》2012,12(10):3291-3299
In the analysis of time invariant fuzzy time series, fuzzy logic group relationships tables have been generally preferred for determination of fuzzy logic relationships. The reason of this is that it is not need to perform complex matrix operations when these tables are used. On the other hand, when fuzzy logic group relationships tables are exploited, membership values of fuzzy sets are ignored. Thus, in defiance of fuzzy set theory, fuzzy sets’ elements with the highest membership value are only considered. This situation causes information loss and decrease in the explanation power of the model. To deal with these problems, a novel time invariant fuzzy time series forecasting approach is proposed in this study. In the proposed method, membership values in the fuzzy relationship matrix are computed by using particle swarm optimization technique. The method suggested in this study is the first method proposed in the literature in which particle swarm optimization algorithm is used to determine fuzzy relations. In addition, in order to increase forecasting accuracy and make the proposed approach more systematic, the fuzzy c-means clustering method is used for fuzzification of time series in the proposed method. The proposed method is applied to well-known time series to show the forecasting performance of the method. These time series are also analyzed by using some other forecasting methods available in the literature. Then, the results obtained from the proposed method are compared to those produced by the other methods. It is observed that the proposed method gives the most accurate forecasts. 相似文献
18.
高校多媒体教室有效性管理探究 总被引:1,自引:0,他引:1
何宇华 《计算机光盘软件与应用》2012,(3):135+139
随着多媒体技术的不断发展及多媒体教学的普及,高校的多媒体教室日益增多,加大了管理的难度。在人力资源有限的情况下,怎样有效管理多媒体教室是亟待解决的问题。本文笔者通过分析管理中出现的问题,测试了多种管理方式,并分析了它们的优缺点,最后确定使用多媒体教室管理系统软件方式来有效管理多媒体教室。 相似文献
19.
γ—TiAl增压涡轮熔模铸造过程数值模拟研究 总被引:9,自引:0,他引:9
根据熔模型壳离心浇注的铸造工艺特点,建立了γ-TiAl增压涡轮凝固传热过程的数值模型,推导了离心压力下γ-TiAl金属间化合物的凝固收缩和补缩过程数学模型,模拟计算了γ-TiAl增压涡轮铸件的温度场和收缩缺陷,结果表明,模型能可靠计算γ-TiAl增压涡轮铸件凝固过程的温度分布和准确预测铸件的收缩缺陷,数值模拟结果与实验结果吻合良好,数值模拟结果证实了前期工作所提出的进一步减少及消除收缩缺陷的优化工艺措施的合理性。 相似文献
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