Consideration of fine-scale coastal oceanography and 3-D acoustics effects for the ESME sound exposure model     

Lynch  J.F. Colosi  J.A. Gawarkiewicz  G.G. Duda  T.F. Pierce  A.D. Badiey  M. Katsnelson  B.G. Miller  J.E. Siegmann  W. Ching-Sang Chiu Newhall  A. 《Oceanic Engineering, IEEE Journal of》2006,31(1):33-48

Results and recommendations for evaluating the effects of fine-scale oceanographic scattering and three-dimensional (3-D) acoustic propagation variability on the Effects of Sound on the Marine Environment (ESME) acoustic exposure model are presented. Pertinent acoustic scattering theory is briefly reviewed and ocean sound-speed fluctuation models are discussed. Particular attention is given to the nonlinear and linear components of the ocean internal wave field as a source of sound-speed inhomogeneities. Sound scattering through the mainly isotropic linear internal wave field is presented and new results relating to acoustic scattering by the nonlinear internal wave field in both along and across internal wave wavefront orientations are examined. In many cases, there are noteworthy fine-scale induced intensity biases and fluctuations of order 5-20 dB.  相似文献   

Real‐time recurrent learning neural network for stream‐flow forecasting     

F.‐John Chang  Li‐Chiu Chang  Hau‐Lung Huang 《水文研究》2002,16(13):2577-2588

Various types of neural networks have been proposed in previous papers for applications in hydrological events. However, most of these applied neural networks are classified as static neural networks, which are based on batch processes that update action only after the whole training data set has been presented. The time variate characteristics in hydrological processes have not been modelled well. In this paper, we present an alternative approach using an artificial neural network, termed real‐time recurrent learning (RTRL) for stream‐flow forecasting. To define the properties of the RTRL algorithm, we first compare the predictive ability of RTRL with least‐square estimated autoregressive integrated moving average models on several synthetic time‐series. Our results demonstrate that the RTRL network has a learning capacity with high efficiency and is an adequate model for time‐series prediction. We also investigated the RTRL network by using the rainfall–runoff data of the Da‐Chia River in Taiwan. The results show that RTRL can be applied with high accuracy to the study of real‐time stream‐flow forecasting networks. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

The shelf-edge frontal structure in the central East China Sea and its impact on low-frequency acoustic propagation     

Ramp  S.R. Ching-Sang Chiu Bahr  F.L. Yiquan Qi Dahl  P.H. Miller  J. Lynch  J.F. Renhe Zhang Jixun Zhou 《Oceanic Engineering, IEEE Journal of》2004,29(4):1011-1031

  相似文献   

A time series of mercury accumulation and improvement of dietary feed in net caged Atlantic salmon (Salmo salar)     

Chou CL 《Marine pollution bulletin》2007,54(6):720-725

The study was undertaken to investigate the uptake of mercury in salmon throughout the entire farming period at the net cage. Mercury concentrations in muscle, liver, kidney, and gill and responses to the various dietary mercury concentrations were determined. The accumulation of mercury is in the order of kidney>gill=liver>muscle. The highest mercury peak concentrations were observed for both kidney and gill at the parr-smolt period, while liver and muscle mercury peaked one month later after caging at the grow-out site. High dietary sodium and calcium fed to the salmon contributed to the elevation of mercury in kidney and gill during the smolting process. The mercury burden over the grow-out period increased sharply with a linear relationship of mercury uptake. The tissue mercury burden per gram of growth was calculated using the slope of mercury burden and the slope of growth over the period of each stage. The results showed dietary mercury loadings on marketable salmon were within tolerance limits of FDA and US EPA. Rapid growth of salmon and low dietary mercury progressively reduces the uptake of mercury in salmon. The time series of mercury monitoring showed that mercury concentrations in salmon were greater at the parr stage in freshwater than at the grow-out stage in salt water.  相似文献   

Barotropic tide in the northeast South China Sea   总被引：2，自引：0，他引：2  

Beardsley  R.C. Duda  T.F. Lynch  J.F. Irish  J.D. Ramp  S.R. Ching-Sang Chiu Tswen Yung Tang Yang  Y.-J. Guohong Fang 《Oceanic Engineering, IEEE Journal of》2004,29(4):1075-1086

A moored array deployed across the shelf break in the northeast South China Sea during April-May 2001 collected sufficient current and pressure data to allow estimation of the barotropic tidal currents and energy fluxes at five sites ranging in depth from 350 to 71 m. The tidal currents in this area were mixed, with the diurnal O1 and K1 currents dominant over the upper slope and the semidiurnal M2 current dominant over the shelf. The semidiurnal S2 current also increased onshelf (northward), but was always weaker than O1 and K1. The tidal currents were elliptical at all sites, with clockwise turning with time. The O1 and K1 transports decreased monotonically northward by a factor of 2 onto the shelf, with energy fluxes directed roughly westward over the slope and eastward over the shelf. The M2 and S2 current ellipses turned clockwise and increased in amplitude northward onto the shelf. The M2 and S2 transport ellipses also exhibited clockwise veering but little change in amplitude, suggesting roughly nondivergent flow in the direction of major axis orientation. The M2 energy flux was generally aligned with the transport major axis with little phase lag between high water and maximum transport. These barotropic energy fluxes are compared with the locally generated diurnal internal tide and high-frequency internal solitary-type waves generated by the M2 flow through the Luzon Strait.  相似文献   

Crustal heterogeneity and subduction processes: 3-D Vp, Vp/Vs and Q in the southern North Island, New Zealand     

Donna Eberhart-Phillips  Martin Reyners  Mark Chadwick  Jer-Ming Chiu 《Geophysical Journal International》2005,162(1):270-288

  相似文献   

Anisotropic seismic ground responses identified from the Hualien vertical array     

Cheng-Hsing Chen  Hwang-Chieh Chiu 《Soil Dynamics and Earthquake Engineering》1998,17(6):371-395

This paper presents the results of ground response analyses using the free-field motions of six earthquakes recorded at the site of the Hualien Large Scale Seismic Test. From the phase spectra of transfer functions between the ground motions recorded at the surface and various depths, the predominant frequencies of soil layers are identified and used to estimate the shear wave velocities of soil layers. Results show that the soils at the Hualien LSST site are anisotropic, such that the earthquake responses exhibit different characteristics in two horizontal principal directions.  相似文献   

Transfer function between wave height and wave pressure for progressive waves: reply to the comments of A. Baquerizo and M.A. Losada     

Yi-Yu Kuo  Jung-Fang Chiu 《Coastal Engineering》1995,24(3-4)

  相似文献   

The Tully–Fisher relation of galaxies at z∼ 0.85 in the DEEP2 survey     

Kuenley Chiu  Steven P. Bamford  Andrew Bunker 《Monthly notices of the Royal Astronomical Society》2007,377(2):806-814

  相似文献   

Intelligent control for modelling of real‐time reservoir operation     

Li‐Chiu Chang  Fi‐John Chang 《水文研究》2001,15(9):1621-1634

This paper presents a new approach to improving real‐time reservoir operation. The approach combines two major procedures: the genetic algorithm (GA) and the adaptive network‐based fuzzy inference system (ANFIS). The GA is used to search the optimal reservoir operating histogram based on a given inflow series, which can be recognized as the base of input–output training patterns in the next step. The ANFIS is then built to create the fuzzy inference system, to construct the suitable structure and parameters, and to estimate the optimal water release according to the reservoir depth and inflow situation. The practicability and effectiveness of the approach proposed is tested on the operation of the Shihmen reservoir in Taiwan. The current M‐5 operating rule curves of the Shihmen reservoir are also evaluated. The simulation results demonstrate that this new approach, in comparison with the M‐5 rule curves, has superior performance with regard to the prediction of total water deficit and generalized shortage index (GSI). Copyright © 2001 John Wiley & Sons, Ltd.  相似文献