An ensemble forecast of the South China Sea monsoon     

T. N. Krishnamurti  Mukul Tewari  Ed Bensman  Wei Han  Zhan Zhang  William K. M. Lau 《大气科学进展》1999,16(2):159-182

1.IntroductionThispaperexploresanensembleforecaststrategyforthelarge--scaletropicalpredictionproblem.Thisisgeneralizedfromarecentstudyontheuseofempiricalorthogonalfunction(EOF)--basedperturbationsforhurricanetrackensembleforecasts,(ZhangandKrishnamur...  相似文献   

Scientific exploration of near‐Earth objects via the Orion Crew Exploration Vehicle     

Paul A. Abell  David J. Korsmeyer  Rob R. Landis  Thomas D. Jones  Daniel R. Adamo  David D. Morrison  Lawrence G. Lemke  Andrew A. Gonzales  Robert Gershman  Theodore H. Sweetser  Lindley L. Johnson  Ed Lu 《Meteoritics & planetary science》2009,44(12):1825-1836

Abstract— A study in late 2006 was sponsored by the Advanced Projects Office within NASA's Constellation Program to examine the feasibility of sending the Orion Crew Exploration Vehicle (CEV) to a near‐Earth object (NEO). The ideal mission profile would involve two or three astronauts on a 90 to 180 day flight, which would include a 7 to 14 day stay for proximity operations at the target NEO. This mission would be the first human expedition to an interplanetary body beyond the Earth‐Moon system and would prove useful for testing technologies required for human missions to Mars and other solar system destinations. Piloted missions to NEOs using the CEV would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while conducting in‐depth scientific investigations of these primitive objects. The main scientific advantage of sending piloted missions to NEOs would be the flexibility of the crew to perform tasks and to adapt to situations in real time. A crewed vehicle would be able to test several different sample collection techniques and target specific areas of interest via extra‐vehicular activities (EVAs) more efficiently than robotic spacecraft. Such capabilities greatly enhance the scientific return from these missions to NEOs, destinations vital to understanding the evolution and thermal histories of primitive bodies during the formation of the early solar system. Data collected from these missions would help constrain the suite of materials possibly delivered to the early Earth, and would identify potential source regions from which NEOs originate. In addition, the resulting scientific investigations would refine designs for future extraterrestrial resource extraction and utilization, and assist in the development of hazard mitigation techniques for planetary defense.  相似文献   

Sand beach ridges record 6000 year history of extreme tropical cyclone activity in northeastern Australia   总被引：1，自引：0，他引：1  

Jonathan Nott  Scott Smithers  Kevin Walsh  Ed Rhodes 《Quaternary Science Reviews》2009,28(15-16):1511-1520

Sand beach ridges are considered to be derived either from aeolian processes and/or waves but their deposition by individual or multiple storms has not been investigated in any detail. We use numerical meteorological and oceanographic models to determine the origin of a sequence of 29 shore parallel sand beach ridges in northeastern Australia. The results suggest that the ridges were constructed by waves and that the final form or height of the ridges is a function of high-energy tropical cyclone generated waves plus storm tides. Hence these landforms archive a nearly 6000 year long history of intense tropical cyclones. The record implies that these extreme tempests occur considerably more frequently than that suggested by the short historical record for this region. The genesis of this sand beach ridge plain has implications for the interpretation of similar sequences elsewhere along the northeast coast of Australia and in comparable environments globally. If other similar sand beach ridge plains have also been deposited by like processes it stands to reason that these long-term records of high intensity tropical cyclones can be used to ascertain a regional scale risk assessment from this hazard.  相似文献   

A dynamic prediction model for time-to-peak     

Mistaya Langridge  Ed McBean  Hossein Bonakdari  Bahram Gharabaghi 《水文研究》2021,35(1):e14032

A simplified empirical equation is developed for widespread prediction of dynamic catchment response time. This model allows for time-to-peak prediction to evolve from static, lumped models, thereby providing a single value for any storm within a given catchment, using a single set of input parameters, that can be applied to a dynamic model, thus accounting for the variability between storm sizes and catchment moisture conditions. These dynamic prediction methods are translated to North America for the first time. This allows the concepts and prediction methods for catchment response time prediction previously established for the United Kingdom (UK), to be translated to a simple empirical equation for use in North America, through the use of selected study areas in Canada and the United States. This reconfigured model is statistically successful in both the UK and North America and allows for a straightforward implementation of dynamic time-to-peak prediction. Further, the reconfigured model introduces the use of a runoff coefficient (R_c) to encompass historical catchment wetness, increasing the ease of incorporating antecedent moisture condition into predictions.  相似文献   

Statistical Study of Network Jets Observed in the Solar Transition Region: a Comparison Between Coronal Holes and Quiet-Sun Regions     

Nancy Narang  Rebecca T. Arbacher  Hui Tian  Dipankar Banerjee  Steven R. Cranmer  Ed E. DeLuca  Sean McKillop 《Solar physics》2016,291(4):1129-1142

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The 2dF Galaxy Redshift Survey: correlation functions, peculiar velocities and the matter density of the Universe   总被引：1，自引：0，他引：1  

Ed Hawkins  Steve Maddox  Shaun Cole  Ofer Lahav  Darren S. Madgwick  Peder Norberg  John A. Peacock  Ivan K. Baldry  Carlton M. Baugh  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Carole Jackson  Bryn Jones  Ian Lewis  Stuart Lumsden  Will Percival  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2003,346(1):78-96

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Settlement Prediction of Model Piles Embedded in Sandy Soil Using the Levenberg–Marquardt (LM) Training Algorithm     

Ameer A. Jebur  William Atherton  Rafid M. Al Khaddar  Ed Loffill 《Geotechnical and Geological Engineering》2018,36(5):2893-2906

This investigation aimed to examine the load carrying capacity of model piles embedded in sandy soil and to develop a predictive model to simulate pile settlement using a new artificial neural network (ANN) approach. A series of experimental pile load tests were carried out on model concrete piles, comprised of three piles with slenderness ratios of 12, 17 and 25. This was to provide an initial dataset to establish the ANN model, in attempt at making current, in situ pile-load test methods unnecessary. Evolutionary Levenberg–Marquardt (LM) MATLAB algorithms, enhanced by T-tests and F-tests, were developed and applied in this process. The model piles were embedded in a calibration chamber in three densities of sand; loose, medium and dense. According to the statistical analysis and the relative importance study, pile lengths, applied load, pile flexural rigidity, pile aspects ratio, and sand-pile friction angle were found to play a key role in pile settlement at different contribution levels, following the order: P?>?δ?>?lc/d?>?lc?>?EA. The results revealed that the optimum model of the LM training algorithm can be used to characterize pile settlement with good degree of accuracy. There was also close agreement between the experimental and predicted data with a root mean square error, (RMSE) and correlation coefficient (R) of 0.0025192 and 0.988, respectively.  相似文献   

Geostatistical Methods for Reservoir Geophysics by Azevedo,L. and Soares,A.     

Michael Ed. Hohn 《Mathematical Geosciences》2018,50(7):861-863

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An event-based approach to understanding decadal fluctuations in the Atlantic meridional overturning circulation     

Lesley Allison  Ed Hawkins  Tim Woollings 《Climate Dynamics》2015,44(1-2):163-190

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Global standard names for the Lowermost Cambrian Series and Stage     

Ed Landing Shanchi Peng Loren E. Babcock Gerd Geyer Malgorzata Moczydlowska- Vidal 《《幕》》2007,30(4):287-289

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