A time domain geoacoustic inversion method using ship noise received on a towed horizontal array is presented. The received signal, containing ship noise as a source of opportunity, is time-reversed and then back-propagated to the vicinity of the ship. The back-propagated signal is correlated with the modeled signal which is expected to peak at the ship's location in case of a good match for th...

In this paper, we establish a theorem on Möbius inversion over power set lattices which strongly generalizes an early result of Whitney on graph colouring.

A gravity inversion method based on the Nettleton-Parasnis technique is used to estimate near surface density in an area without exposed outcrop or where outcrop occurrences do not adequately represent the subsurface rock densities. Its accuracy, however, strongly depends on how efficiently the regional trends and very local (terrain) effects are removed from the gravity anomalies processed. Ne...

First attempts for the estimation of above ground forest biomass (AGB) by means of SAR, have used allometric equations to calculate biomass from the estimated PolInSAR forest height. However, changes in forest density or structure bias the known allometric relations. Today, remote sensing systems like SAR are able to measure additional parameters like vertical forest structure [1] [2]. In this ...

Aims Data assimilation is a useful tool to extract information from large datasets of the net ecosystem exchange (NEE) of CO2 obtained by eddy-flux measurements. However, the number of parameters in ecosystem models that can be constrained by eddy-flux data is limited by conventional inverse analysis that estimates parameter values based on one-time inversion. This study aimed to improve data a...

this paper proposes a method for the prediction of pore size values in hydrocarbon reservoirs using 3d seismic data. to this end, an actual carbonate oil field in the south-western part ofiranwas selected. taking real geological conditions into account, different models of reservoir were constructed for a range of viable pore size values.  seismic surveying was performed next on these models. f...

air pollution is one of the most important problems in urban areas that always threaten citizen's health. photochemical smog is one of the main factors of air pollution in large cities like tehran. usually smog is not only a part of nature, but is being analyzed as an independent matter, which highly affects on the nature. it has been used as relationship between atmospheric elements such as te...

helicopter-borne electromagnetic (hem) is a fast and high resolution airborne electromagnetic (aem) method that is frequently used for imaging of the subsurface resistivity structures. this is a versatile and cost effective method, frequently has used in mineral and groundwater exploration and various environmental problems. modern frequency-domain hem systems utilize small electromagnetic, mag...

The possibility of spectrum inversion has been debated since it was raised by and is still discussed because of its implications for functionalist theories of conscious experience (e.g., Palmer, 1999). This paper provides a mathematical formulation of the question of spectrum inversion and proves that such inversions, and indeed bijective scramblings of color in general, are logically possible....