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基于S7-300PLC的水库测流监控系统的设计 被引量:4
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作者 邢珂 黄民改 《华北水利水电学院学报》 2011年第5期89-91,共3页
为实现水库监控自动化,采用西门子S7-300PLC和画面组态技术设计了一种新型水库水流测速监控系统,给出了系统部分的程序设计,并详细介绍了测速监控系统的硬件构成和PLC的配置,以供相似设计参考.
关键词 S7300 水库 水流测流
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Calculation of wave and current loads on launching offshore jacket 被引量:6
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作者 ZHANG Guang-fa JI Zhuo-shang LI Tie-li LIN Yan 《Journal of Marine Science and Application》 2006年第4期1-7,共7页
It’s very complicated to calculate and analyze the wave and current loads on naval architectures since the sea condition is uncertain and complicated and the determinants vary from different form types and dimensions... It’s very complicated to calculate and analyze the wave and current loads on naval architectures since the sea condition is uncertain and complicated and the determinants vary from different form types and dimensions. For calculating the wave and current loads on upright small-long-size pipe, the Morrison equation is practical and applied. Jacket platform is a kind of offshore space frame structure comprised of lots of poles that are circular cylinders with small diameter and in the oblique status relative to seabed. In this paper, based on Morrison equation, the specific method and procedure calculating the wave and current loads on launching jacket are given and applied on a typical launching jacket. The instance shows that the method and procedure are convenient and make the calculation and analysis in good agreement with actual launching. 展开更多
关键词 LAUNCHING hydrodynamic force morrison equation jacket platform
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Application of empirical mode decomposition based energy ratio to vortex flowmeter state diagnosis 被引量:4
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作者 孙志强 张宏建 《Journal of Central South University》 SCIE EI CAS 2009年第1期154-159,共6页
To improve the measurement performance, a method for diagnosing the state of vortex flowmeter under various flow conditions was presented. The raw sensor signal of the vortex flowmeter was adaptively decomposed into i... To improve the measurement performance, a method for diagnosing the state of vortex flowmeter under various flow conditions was presented. The raw sensor signal of the vortex flowmeter was adaptively decomposed into intrinsic mode functions using the empirical mode decomposition approach. Based on the empirical mode decomposition results, the energy of each intrinsic mode function was extracted, and the vortex energy ratio was proposed to analyze how the perturbation in the flow affected the measurement performance of the vortex flowmeter. The relationship between the vortex energy ratio of the signal and the flow condition was established. The results show that the vortex energy ratio is sensitive to the flow condition and ideal for the characterization of the vortex flowmeter signal. Moreover, the vortex energy ratio under normal flow condition is greater than 80%, which can be adopted as an indicator to diagnose the state of a vortex flowmeter. 展开更多
关键词 flow state diagnosis energy ratio vortex flowmeter empirical mode decomposition
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Impact of Climate Change on Regional Hydroclimate Projection in Peninsular Malaysia
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作者 Mohd Ekhwan Toriman Mazlin Bin Mokhtar +3 位作者 Rahmah E1-fithri NorAzlina Abdul Aziz Md.Pauzi Abdullah Muhamad Barzani Gasim 《Journal of Environmental Science and Engineering(A)》 2012年第1期41-45,共5页
For the assessment of the impact of future climate change on the hydrologic regime and water resources of Peninsular Malaysia, it is necessary to downscale the climate change simulations of a coarse scale General Circ... For the assessment of the impact of future climate change on the hydrologic regime and water resources of Peninsular Malaysia, it is necessary to downscale the climate change simulations of a coarse scale General Circulation Model to the region of Peninsular Malaysia at fine grid resolution. This paper presents a desktop review of the state of climate change parameters, namely rainfall and river flow over the Peninsular Malaysia for the 2041-2050 projection period. Analysis of the results from the models shows there will be a substantial increase in mean monthly precipitation over the North East Coastal region from historical 259.5 mm to 281.5 mm, from 289.0 mm to 299.0 mm and 221.8 mm to 239.5 mm over Terengganu and Kelantan, respectively. Meanwhile, for river flow projection, it will be an expected increase in interannual and intraseasonal variability with increased hydrologic extremes (higher high flows, and lower low flows) at Kelantan, Pahang, Terengganu, and Kedah watersheds in the future. 展开更多
关键词 Climate change peninsular Malaysia RAINFALL river flow.
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A Different Light in Predicting Ungauged Basins: Regionalization Approach Based on Eastern USA Catchments 被引量:2
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作者 Syed Abu Shoaib Andras Bardossy +2 位作者 Thorsten Wagener Yingchun Huang Nahid Sultana 《Journal of Civil Engineering and Architecture》 2013年第3期364-378,共15页
This paper reviewed the existing methods in regionalization studies to predict ungauged catchments and considering all the aspects a different methodology is developed, which is named as RDS method. ROPE (robust para... This paper reviewed the existing methods in regionalization studies to predict ungauged catchments and considering all the aspects a different methodology is developed, which is named as RDS method. ROPE (robust parameter estimation)-D (data depth)-S (spatial proximity) together gets this name RDS. Catchment properties and hydrological model parameters are used consistently to predict ungauged basin. This study explores the potential of the regionalization process to predict ungauged basins using the data of the Eastern USA catchments. Two conceptual rainfall-runoff hydrological models: HYMOD and HBV are used in this study. Analysis shows 95% success in predicting ungauged basins with HBV and 90% success with HYMOD. It is undoubtedly perceptible that RDS method is very effective in predicting ungauged basin and regionalization is independent of the conceptual rainfall-runoff model. 展开更多
关键词 Ungauged basin rainfall-runoff modeling REGIONALIZATION robust parameter.
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With the Measuring Rod against the Floods: Ferdinand Verbiest and His Forgotten Introduction of Benedetto Castelli’s River Hydraulics to China
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作者 Albert KOENIG Sabine KINK 《Chinese Annals of History of Science and Technology》 2022年第2期49-119,共71页
The monumental Studies to Fathom Principles(Qiongli xue窮理學;1683)by Ferdinand Verbiest S.J.(Nan Huairen南懷仁,1623–1688)was never printed,and its exact content is not known.A section of the only extant,though incom... The monumental Studies to Fathom Principles(Qiongli xue窮理學;1683)by Ferdinand Verbiest S.J.(Nan Huairen南懷仁,1623–1688)was never printed,and its exact content is not known.A section of the only extant,though incomplete,manuscript deals with fluvial flood prevention and river control measures,a subject that until then had not cropped up in any Chinese-language work of the Jesuits.In this section,Verbiest not only described the already well-known Aristotelian theory of the origin of rivers,but also introduced to China new scientific propositions,concepts,and numerical examples originating from the seminal Renaissance work Della misura dell’acque correnti(Of the Mensuration of Running Waters;1628)by Benedetto Castelli(1578–1643).In addition,Verbiest presented to his readers some noteworthy examples of pertinent Western achievements such as the pound-lock with miter gate,and he provided them with a simple economic analysis of flood control options.The significance and possible influence of Verbiest’s text on further developments in Chinese approaches to water engineering are discussed,highlighting a hitherto largely disregarded facet of Western science and technology transfer in the field of river hydraulics and flood management. 展开更多
关键词 Ferdinand Verbiest Benedetto Castelli Qiongli xue Della misura dell’acque correnti HYDROLOGY river hydraulics flood prevention Kangxi period
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Mixture temperature prediction of waxy oil–water two-phase system flowing near wax appearance temperature
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作者 Ali Piroozian Muhammad A. Manan +4 位作者 Issham Ismail Rahmat Mohsin Ali Esfandyari Bayat Mac DarlingtonUche Onuoha Mahmoud Hemmati 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第6期795-802,共8页
Temperature sensitivity of waxy crude oils makes it difficult to study their flow behaviour in the presence of water especially near their wax appearance temperature (WAT). In this study a method was proposed and im... Temperature sensitivity of waxy crude oils makes it difficult to study their flow behaviour in the presence of water especially near their wax appearance temperature (WAT). In this study a method was proposed and implemented to mitigate such difficulties which was applied in predicting mixture temperatures (Tin) of a typical Malaysian waxy crude oil and water flow in a horizontal pipe. To this end, two analytical models were derived firstly from calorimetry equation which based on developed two correlations for defining crude oil heat capacity actualized from the existed specific heat capacities of crude oils. The models were then applied for a set of experiments to reach the defined three predetermined Tm (26 ℃, 28 ℃ and 30 ℃). The comparison between the predicted mixture temperatures (Tin,1 and Tin,2) from the two models and the experimental results displayed acceptable absolute average errors (0.80% 0.62%, 0.53% for model 1; 0,74%, 0.54%, 0.52% for model 2). Moreover, the average errors for both models are in the range of standard error limits (4-0,75Z) according to ASTM E230. Conclusively, the proposed model showed the ease of obtaining mixture temperatures close to WAT as predetermined with accuracy of ± 0.5 ℃approximately for over 84% of the examined cases. The method is seen as a practical reference point to further study the flow behaviour of waxy crudes in oil-water two-phase flow system near sensitive temperatures. 展开更多
关键词 Mixture temperature predictionAnalytical modelWaxy oil-water two-phase flowWax appearance temperature
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