结合有人和无人驾驶船观测以及长期定点观测计算寒潮过境引起的海水输运     

WEEKS Eddie  ROBINSON Mark E  李春雁 《海洋学报(英文版)》2018,37(11):1-7

高分辨率的数据对于理解近海的复杂过程以及制定有效的管理措施日益重要,特别是考虑到恶劣气象的长期效应。这种长期效应的积累可以与潮汐的长期效应一样重要。本文讨论的即是一个大气锋面过境的过程对于Vermilion Bay水输运的影响。我们的研究采用了有人船和自制的无人船作为载具来测量流速剖面。这种自制无人船造价低廉、简单实用、可控性好,可以做比有人船更精确的测量。我们采用安装在这些观测载具上的多普勒流速剖面仪在一个潮周期内反复对流速的横向和垂向断面的水通量做高分辨率的精准测量,然后与一个定点的多普勒流速剖面仪的流速做相关分析得出相关系数。利用所求相关系数把水通量的计算扩展到总共717天的定点观测时间段,以此讨论在这个期间最强的一次大气寒潮过境时产生的水输运并阐述此类过程的重要性。  相似文献   

Exploring fishing dependence in gulf coast communities     

Steve Jacob  Priscilla Weeks  Benjamin G. Blount  Michael Jepson 《Marine Policy》2010

Two unrelated data sources (quantitative secondary data and qualitative primary data) and mixed methodologies (statistical analysis and ethnography) are used to define the concept of, and develop indicators for, fishing dependence. Techniques for integrating differing data sources are developed. Comparisons of the qualitative rankings with the quantitative rankings were, overall, positive and statistically significant. The process used thus confirmed that the indicators were reliable measures for fishing dependence. In terms of external validity and triangulation, the process used was more rigorous than using ethnography “after-the-fact” to ground-truth the quantitative indicators.  相似文献   

Grain size, areal thickness distribution and controls on sedimentation of the 1991 Mount Pinatubo tephra layer in the South China Sea     

Martin G. Wiesner  Andreas Wetzel  Sandra G. Catane  Eddie L. Listanco  Hannah T. Mirabueno 《Bulletin of Volcanology》2005,67(5):490-495

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Evaluation of a digital echo sounder system for detection of submersed aquatic vegetation   总被引：1，自引：0，他引：1  

Bruce M. Sabol  R. Eddie Melton  Robert Chamberlain  Peter Doering  Kathy Haunert 《Estuaries and Coasts》2002,25(1):133-141

A technique is presented for rapid detection of submersed aquatic vegetation (SAV) using a high-frequency, high-resolution digital echo sounder linked with global positioning system equipment. The acoustic reflectivity of SAV allows for detection and explicit meaqsurement of canopy geometry using a digital signal processing algorithm described here. Comparing output data from this system with physical measurements shows good detection and measurement performance over a wide range of conditions for freshwater tape grass (Vallisneria americana) and seagrasses (Thalassia testudinum, Halodule wrightii, andSyringodium filiforme) in a sandy-bottom, south Florida estuary. The range of environmental conditions for which the system can be used is defined. Based on these measured performance data and a review of existing literature, this system appears to fill a gap in the inventory of established methods for measuring the distribution and abundance of submersed macrophytes.  相似文献   

Book review     

Peter Molnar  John D. Weeks  Claude J. Allegre  Yehuda Bock  Stephen K. Dobos  Leszek Czechowski  Kacper R. Rybicki  Krzysztof Haman 《Pure and Applied Geophysics》1987,125(4):679-698

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Mapping of settlements in high-resolution satellite imagery using high performance computing     

Anil Cheriyadat  Eddie Bright  David Potere  Budhendra Bhaduri 《GeoJournal》2007,69(1-2):119-129

Classifying urban land cover from high-resolution satellite imagery is challenging, and those challenges are compounded when the imagery databases are very large. Accurate land cover data is a crucial component of the population distribution modeling efforts of the Oak Ridge National Laboratory’s (ORNL) LandScan Program. Currently, LandScan Program imagery analysts manually interpret high-resolution (1–5 m) imagery to augment existing satellite-derived medium (30 m) and coarse (1 km) resolution land cover datasets. For LandScan, the high-resolution image archives that require interpretation are on the order of terabytes. The goal of this research is to automate human settlement mapping by utilizing ORNL’s high performance computing capabilities. Our algorithm employs gray-level and local edge-pattern co-occurrence matrices to generate texture and edge patterns. Areas of urban land cover correlate with statistical features derived from these texture and edge patterns. We have parallelized our algorithms for implementation on a 64-node system using a single instruction multiple data programming model (SIMD) with Message Passing Interface (MPI) as the communication mode. Our parallel-configured classifier performs 30–40 times faster than stand-alone alternatives. We have tested our system on IKONOS imagery. The early results are promising, pointing towards future large-scale classification of human settlements at high-resolution.  相似文献   

Evaluation of Near‐Critical Overdamping Effects in Slug‐Test Response     

E.P. Weeks  A.C. Clark 《Ground water》2013,51(5):775-780

A slug test behaves as a harmonic oscillator, subject to both inertial effects and viscous damping. When viscous and inertial forces are closely balanced, the system is nearly critically damped, and water‐level recovery is affected by inertial effects, but does not exhibit oscillation. These effects were investigated by use of type curves, generated both by modification of Kipp's (1985) computer program and by use of the Butler‐Zhan (2004) model. Utility of the type curves was verified by re‐analysis of the Regina slug test previously analyzed by Kipp. These type curves indicate that near‐critical inertial effects result in early‐time delayed water‐level response followed by merger with, or more rapid recovery than, response for the fully damped case. Because of this early time response, slug tests in the moderately over‐damped range are best analyzed using log‐log type curves of (1 ? H/H₀) vs. Tt/. Failure to recognize inertial effects in slug test data could result in an over‐estimate of transmissivity, and a too‐small estimate of storage coefficient or too‐large estimate of well skin. However, application of the widely used but highly empirical Hvorslev (1951) method to analyze both the Regina slug test and type‐curve generated data indicate that such analyses provide T values within a factor of 2 of the true value.  相似文献   

The NTHMP Tsunameter Network     

Frank?I.?GonzálezEmail author  Eddie?N.?Bernard  Christian?Meinig  Marie?C.?Eble  Harold?O.?Mofjeld  Scott?Stalin 《Natural Hazards》2005,35(1):25-39

A tsunameter (soo-NAHM-etter) network has been established in the Pacific by the National Oceanic and Atmospheric Administration. Named by analogy with seismometers, the NOAA tsunameters provide early detection and real-time measurements of deep-ocean tsunamis as they propagate toward coastal communities, enabling the rapid assessment of their destructive potential. Development and maintenance of this network supports a State-driven, high-priority goal of the U.S. National Tsunami Hazard Mitigation Program to improve the speed and reliability of tsunami warnings. The network is now operational, with excellent reliability and data quality, and has proven its worth to warning center decision-makers during potentially tsunamigenic earthquake events; the data have helped avoid issuance of a tsunami warning or have led to cancellation of a tsunami warning, thus averting potentially costly and hazardous evacuations. Optimizing the operational value of the network requires implementation of real-time tsunami forecasting capabilities that integrate tsunameter data with numerical modeling technology. Expansion to a global tsunameter network is needed to accelerate advances in tsunami research and hazard mitigation, and will require a cooperative and coordinated international effort.  相似文献   

Well-proportioned universes suppress the cosmic microwave background quadrupole     

J. Weeks  J.-P. Luminet †  A. Riazuelo †  R. Lehoucq † 《Monthly notices of the Royal Astronomical Society》2004,352(1):258-262

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Radio continuum surveys     

Justin L. Jonas  Eddie E. Baart 《Astrophysics and Space Science》1995,230(1-2):351-358

The Rhodes University radio astronomy group has been involved in radio continuum mapping of southern extended radio sources since 1976. We describe the various mapping projects undertaken with the HartRAO telescope, particularly the Rhodes/HartRAO 2300 MHz all-sky survey, and speculate on future projects.  相似文献