The use of Current Data in Ocean Outfall Design

1986 ◽  
Vol 18 (11) ◽  
pp. 111-120 ◽  
Author(s):  
Philip J. W. Roberts
Keyword(s):  
Time Series ◽  
San Francisco ◽  
Coastal Waters ◽  
Puget Sound ◽  
Current Data ◽  
Far Field ◽  
Initial Dilution ◽  
Visitation Frequency ◽  
Time Series Analyses ◽  
Ocean Outfall

Some of the ways in which current meter data can aid in the design of ocean outfalls are discussed. Examples are given, which include time series analyses of currents obtained in Puget Sound, near Alki Point, the prediction of initial dilution of San Francisco, the prediction of far field dilution and transport in Southern California coastal waters, and prediction of the visitation frequency, or transport probability, off Alki Point.

Far field modeling of the Mamala Bay outfalls

1998 ◽  
Vol 38 (10) ◽  
pp. 323-330
Author(s):  
Philip J. W. Roberts
Keyword(s):  
Field Model ◽  
Near Field ◽  
Far Field ◽  
Field Modeling ◽  
Visitation Frequency ◽  
Statistical Variation ◽  
Long Time ◽  
Harmonic Average ◽  
Ocean Outfall ◽  
Acoustic Doppler Current Profilers

The results of far field modeling of the wastefield formed by the Sand Island, Honolulu, ocean outfall are presented. A far field model, FRFIELD, was coupled to a near field model, NRFIELD. The input data for the models were long time series of oceanographic observations over the whole water column including currents measured by Acoustic Doppler Current Profilers and density stratification measured by thermistor strings. Thousands of simulations were made to predict the statistical variation of wastefield properties around the diffuser. It was shown that the visitation frequency of the wastefield decreases rapidly with distance from the diffuser. The spatial variation of minimum and harmonic average dilutions was also predicted. Average dilution increases rapidly with distance. It is concluded that any impact of the discharge will be confined to a relatively small area around the diffuser and beach impacts are not likely to be significant.

Dilution and Transport Predictions for Ocean Outfalls

1989 ◽  
Vol 21 (8-9) ◽  
pp. 969-979 ◽  
Author(s):  
Philip J. W. Roberts
Keyword(s):  
Travel Time ◽  
Rio De Janeiro ◽  
Stratified Flows ◽  
Far Field ◽  
Ocean Bottom ◽  
Bacterial Mortality ◽  
Visitation Frequency ◽  
Ocean Outfall

Dilution and transport predictions for an ocean outfall proposed for the Barra da Tijuca, Rio de Janeiro are summarized. The initial characteristics of the wastefield are predicted using the results of recent experiments on submerged wastefield characteristics in stratified flows. Using measured currents and stratifications, it is predicted that the proposed design will result in a wastefield which is always submerged, whose thickness varies from 8.5 to 23.1 m and whose dilution varies from about 200 to well over 2000. The wastefield will often stay near the ocean bottom. Far field transport due to currents is calculated and expressed in terms of spatial “visitation frequency,” the probability of the wastefield visiting any location. It is shown that no effluent reaches shore with a travel time less than 5.5 hours, and computations including oceanic diffusion and bacterial mortality suggest maximum shoreline coliform concentrations of 500 per 100 mℓ, and 98% of the time they will be less than this. For reasons discussed these estimates of shoreline bacteria are conservatively high, and much lower than computed by methods assuming steady onshore currents.

Modeling of Ocean Outfall Discharges

1992 ◽  
Vol 25 (9) ◽  
pp. 155-164 ◽  
Author(s):  
P. J. W. Roberts ◽  
N. Williams
Keyword(s):  
San Francisco ◽  
Current Speed ◽  
Decay Rates ◽  
Spatial And Temporal Variation ◽  
Spatial And Temporal Variability ◽  
Mixing Processes ◽  
Initial Dilution ◽  
Oceanic Turbulence ◽  
Field Diffusion ◽  
Ocean Outfall

Bacterial modeling techniques for the San Francisco ocean outfall are reviewed. Extensive oceanographic measurements, and field and laboratory experiments were done. The oceanographic data are briefly reviewed and it is shown that all parameters are subject to considerable spatial and temporal variability. A “wandering puff” model is used to compute the frequency distribution of shoreline bacteria. The model accounts for varying initial dilution due to variation in stratification, current speed and direction, and effluent flowrate, far field diffusion due to oceanic turbulence, spatial and temporal variation in current speed and direction, and diurnal variation in bacterial decay rates. It is predicted that bacterial concentration standards will be met at all shoreline locations without effluent chlorination. Areas of uncertainties in our present knowledge of mixing processes are briefly reviewed, and likely future trends discussed.

scholarly journals Time series analyses reveal transient relationships between abundance of larval anchovy and environmental variables in the coastal waters southwest of Taiwan

2009 ◽  
Vol 18 (2) ◽  
pp. 102-117 ◽  
Author(s):  
CHIH-HAO HSIEH ◽  
CHIH-SHIN CHEN ◽  
TAI-SHENG CHIU ◽  
KUO-TIEN LEE ◽  
FENG-JEN SHIEH ◽  
...  
Keyword(s):  
Time Series ◽  
Coastal Waters ◽  
Environmental Variables ◽  
Time Series Analyses

Time‐series analyses of firearm‐related Google searches and U.S. suicide rates 2004–2016

2021 ◽  
Author(s):  
Daniel W. Capron ◽  
Rita Andel ◽  
Martin Voracek ◽  
Benedikt Till ◽  
Thomas Niederkrotenthaler ◽  
...  
Keyword(s):  
Time Series ◽  
Suicide Rates ◽  
Time Series Analyses

scholarly journals Comparative Time Series Analysis of Perceptual Responses to Electroacoustic Music

2012 ◽  
Vol 29 (4) ◽  
pp. 359-375 ◽  
Author(s):  
Freya Bailes ◽  
Roger T. Dean
Keyword(s):  
Time Series ◽  
Sound Intensity ◽  
Electroacoustic Music ◽  
Affective Content ◽  
Musical Expertise ◽  
Perceived Change ◽  
Time Series Analyses ◽  
Time Perceptions ◽  
The Relationship ◽  
Acoustic Measure

this study investigates the relationship between acoustic patterns in contemporary electroacoustic compositions, and listeners' real-time perceptions of their structure and affective content. Thirty-two participants varying in musical expertise (nonmusicians, classical musicians, expert computer musicians) continuously rated the affect (arousal and valence) and structure (change in sound) they perceived in four compositions of approximately three minutes duration. Time series analyses tested the hypotheses that sound intensity influences listener perceptions of structure and arousal, and spectral flatness influences perceptions of structure and valence. Results suggest that intensity strongly influences perceived change in sound, and to a lesser extent listener perceptions of arousal. Spectral flatness measures were only weakly related to listener perceptions, and valence was not strongly shaped by either acoustic measure. Differences in response by composition and musical expertise suggest that, particularly with respect to the perception of valence, individual experience (familiarity and liking), and meaningful sound associations mediate perception.

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