Read and Answer: De-noising sea noise data....

1) De-noising sea noise data

This work presents De-noising sea noise data and also how data from a marine seismic survey, which is highly contaminated by noise, was de-noised through the use of a time-frequency filter. In addition to the present standard work flow designed to remove cavitation noise, strumming noise and swell-noise. We introduce a new approach to track seismic interference. This is done by applying time-frequency de-noising on the slowness that gathers. As a motivation and background for the processing we also explain some of the techniques behind the generation of the many different noise types.

The end story is that even in case low if there is a low quality input data then also it can be turned into high quality seismic sections. Even though the dataset used is only one, the results and its methodologies represented here are considered to be general, and should be definitely applicable to a large number of seismic surveys.

Questions:

a) Name the two components which seismic data consists of? 

b) What is the second problem in this dataset?

c) What is the frequency range of swell noise?

d) What is the frequency range of hydrostatic pressure variation noise?

Sol:

a) signal and a noise component

b) Swell-noise

c) (1-10(15)Hz)

d) (0-1(2)Hz)

Read and Answer: Passive acoustic techniques to study sound producing fish species...

1) Passive acoustic techniques to study sound producing fish species

A wide variety of taxa fish produce sound. The behavior of Sound production gives an opportunity to study and analyze various aspects of fish biology, such as habitat selection and spawning behavior, in a very non-invasive manner. Passive acoustics is an active area of research called ichthyologic research. However, fish bio-acousticians have not published their research details in the fisheries literature. Therefore, fisheries scientists may not be aware of progress being made in this field completely or the potential uses for acoustic techniques passively. The physiological, behavioral and evolutionary aspects of sound production by fishes generally investigate the patterns of research publication on sound production by the fish and also review the literature which is based on the passive acoustic methods application to the research of fisheries and finally predicts and tells different ways of passive acoustic surveys which is being designed to optimize the quality and quantity of information obtained. Passive acoustic methods can be definitely attractive as well as alternative or it may supplement to the other traditional fisheries based on assessment techniques since they are non-invasive, and also can be conducted at low cost, which covers a large study area at temporal resolution and high spatial.

Questions:

a) Name the fish which produces sound?

b) Which are the three aspects of sound production?

c) Which acoustic method can be attractive?

d) What can be the Passive acoustic methods?

Sol:

1. Taxa
2. Physiological, behavioral and evolutionary aspects.
3. Passive acoustic method.
4. non-invasive