Abstract: A method and system for correcting seismic survey signals for separating and correcting for the effects of azimuthal anisotropy caused by the overburden, rather than the subsurface reflectivity, is disclosed. Following an initial estimate and normal moveout correction of the traces in a common midpoint gather, analytical traces are generated for coefficient series corresponding to zero-offset travel time response and to the azimuthal anisotropy, over the corrected gather. The quadrature-phase component of the azimuthal anisotropy coefficient series relative to the zero-offset travel time coefficient series indicates the effects of overburden azimuthal anisotropy, while the in-phase component indicates the effects of azimuthal anisotropy from subsurface reflective interfaces. Additional normal moveout correction to correct for the overburden azimuthal anisotropy may then be performed.

Abstract: Mechanically and thermally improved rechargeable batteries, modules and fluid-cooled battery pack systems. The battery is prismatic in shape with an optimized thickness to width to height aspect ratio which provides the battery with balanced optimal properties when compared with prismatic batteries lacking this optimized aspect ratio. The optimized thickness, width and height allow for maximum capacity and power output, while eliminating deleterious side affects. The battery case design allows for unidirectional expansion which is readily compensated for by applying external mechanical compression counter to that direction. In the module, the batteries are bound within a module bundling/compression means under external mechanical compression which is optimized to balance outward pressure due to expansion and provide additional inward compression to reduce the distance between the positive and negative electrodes, thereby increasing overall battery power.

Abstract: A high capacity long cycle life positive electrode which includes an electronically conductive substrate for conducting electricity through the electrode and an electrochemically active nickel hydroxide material in electrical contact with the electronically conductive substrate, the electrochemically active nickel hydroxide material is composed of at least two different solid solution nickel hydroxide materials each having differing compositions. The positioning of the at least two different solid solution nickel hydroxide materials and their relative compositions alter the local redox potential or porosity to force discharge of the electrode in a stepwise fashion from the nickel hydroxide material remote from said conductive network or substrate, through any intermediate nickel hydroxide materials, to the nickel hydroxide material adjacent the conductive network or substrate.

Abstract: Nickel-metal hydride batteries and electrodes are capable of increased power output and recharge rates. The electrodes and batteries produced therefrom exhibit increased internal conductance. The positive and negative electrodes may be formed by pressing powdered metal-hydride active materials into porous metal substrates. The porous metal substrates are formed from copper, copper-plated nickel, or a copper-nickel alloy, and may be additionally plated with a material which is electrically conductive and resistant to corrosion in the battery environment, such as nickel.

Abstract: A method and computer system for applying corrections to dual sensor ocean bottom cable marine seismic signals, for purposes of eliminating ghosts and reverberations, are disclosed. According to the disclosed method and system, both phase and amplitude corrections are derived in common receiver gathers, and applied to each geophone trace in the gather; preferably, the derivation of the corrections is performed on a limited offset common receiver gather. The phase correction is determined by minimizing a folded cross-correlation of the hydrophone and geophone signals over varying phase angles, with the appropriate phase correction corresponding to the angle at which the minimum is obtained; preferably, stacked cross-correlations are used in the phase correction determination to reduce the effects of random noise. The phase correction is then applied to the geophone traces in the gather, and an amplitude correction is derived by minimizing a cross-ghosting relationship.

Abstract: A method of separating the effects of the earth response on vibratory energy from individual ones of multiple vibrators to geophones, in generating a seismic survey, is disclosed. According to the disclosed method, measurements of the actual vibrations generated at the source are made, in addition to the geophone measurements of the refracted and reflected vibrations, both over a number of frequency sweeps. The source and geophone vibrations are first transformed into frequency domain representations, by way of Discrete Fourier Transforms. An inverse matrix of the recorded frequency-domain source vibrations is then generated for each frequency. When the number of sweeps equals the number of vibrators, the inverse matrix is merely the multiplicative inverse of the source measurements; if the number of sweeps exceeds the number of vibrators, the inverse matrix is the generalized inverse of the original matrix.

Abstract: A method of separating the effects of the earth response on vibratory energy from individual ones of multiple vibrators to geophones, in generating a seismic survey, is disclosed. According to the disclosed method, measurements of the actual vibrations generated at the source are made, in addition to the geophone measurements of the refracted and reflected vibrations, both over a number of frequency sweeps. The source and geophone vibrations are first transformed into frequency domain representations, by way of Discrete Fourier Transforms. An inverse matrix of the recorded frequency-domain source vibrations is then generated for each frequency. When the number of sweeps equals the number of vibrators, the inverse matrix is merely the multiplicative inverse of the source measurements; if the number of sweeps exceeds the number of vibrators, the inverse matrix is the generalized inverse of the original matrix.

Abstract: A computer system and method for eliminating the effects of ghost reflections from marine seismic survey traces obtained via ocean bottom cables are disclosed. Dual sensors are used in the ocean bottom cables, to obtain both pressure and velocity traces. The disclosed method combines, in a common receiver gather, the corresponding pressure and velocity traces for each source-receiver path using several values of a scalar value that serves as a weighting factor. Conventional corrections and filtering, including spiking deconvolution, are applied to the combined traces, and the combined traces for each value of the scalar are stacked over a limited offset range. Autocorrelation and other spectral techniques may be applied to identify the residuals of the ghost reflections using each of the multiple scalar values; the optimal value may then be selected, for each common receiver gather, as that which has the minimum ghost reflection residuals.

Abstract: A method for correction of seismic data for taking into account azimuthal anisotropy in the subsurface is described. The data is corrected using an azimuthally anisotropic normal moveout equation, thereby yielding better signal to noise ratio as well as providing valuable information as to the degree and direction of azimuthal anisotropy in the subsurface.

Abstract: A positive electrode material for use in electrochemical cells. This material comprises particles of positive electrode material including at least one electrochemically active hydroxide and a substantially continuous, uniform, encapsulant layer surrounding the particles of positive electrode material. The encapsulant layer is formed from a material which, upon oxidation during processing or during charging of the electrode, is convertible to a highly conductive form, and which, upon subsequent discharge of the electrode, does not revert to its previous form. Preferably, the electrochemically active hydroxide includes at least nickel hydroxide. The encapsulant layer is preferably formed from at least cobalt hydroxide or cobalt oxyhydroxide. This layer is formed on the particles of positive electrode material by precipitation from a cobalt salt solution, which can be a cobalt sulfate solution. Also disclosed are positive electrodes including the material and a precipitation method of forming the material.

Abstract: A high capacity, long cycle life positive electrode for use in an alkaline rechargeable electrochemical cell comprising: a solid solution nickel hydroxide material having a multiphase structure that comprises at least one polycrystalline .gamma.-phase including a polycrystalline .gamma.-phase unit cell comprising spacedly disposed plates with at least one chemical modifier incorporated around the plates, the plates having a range of stable intersheet distances corresponding to a 2.sup.+ oxidation state and a 3.5.sup.+, or greater, oxidation state; and at least one compositional modifier incorporated into the solid solution nickel hydroxide material to promote the multiphase structure.

Abstract: A vertical gradient estimation technique is used to separate downgoing seismic ghost wavefields. The upgoing reflected seismic wavefield, allows the ghost wavefield to be attenuated to improve signal-to-noise ratio. The vertical gradient estimation technique is applicable to both marine seismic surveying using towed hydrophones, and to land seismic surveying using buried geophones. The technique allows the vertical signal gradient to be estimated from seismic signals measured at a single depth, and is based on a relationship between the measured seismic signals, and the source signature and the Green's function for the survey media. The technique involves determning (20) the source signature for the seismic source, and determining (21) the Green's function for the survey media. Seismic signals are then measured (22). These data are then processed to estimate (24) the vertical signal gradient as a function of source signature, Green's function and the measured seismic signals.

Abstract: An alkaline electrolytic hydrogen generator having an anode including a low oxygen overpotential catalyst comprising a composite hydrous oxide of nickel and iron in which the nickel content varies from about 0.6 to about 19 parts nickel per part iron. The catalyst will preferably comprise an electrochemically coprecipitated coating on a conductive substrate.

Abstract: An electrochromic device useful as a smart window comprises a pair of transparent doped tin oxide layers that serve as the terminal electrodes, and between which are sandwiched an electrochemical cell including a layer of electrochromic material and between the layer of electrochromic material and its proximate termial is inserted a layer of tin oxide whose normal resistance is large compared to the lateral resistance of the proximate doped tin oxide layer. This serves to improve the lateral uniformity of the potential applied to the electrochemical cell when a voltage is applied across the terminal electrodes with a resultant improvement in the uniformity of coloring and bleaching across the surface of the electrochromic layer.

Abstract: An improvement in a method of treating seismic data in which predictive noise, as measured along one of the axes is discriminated and subtracted from the total signal along another of the axes recorded by geophone recording the reflection from subterranean strata of energy input from a source at the surface.

Abstract: A nonsintered NiOOH electrode for an alkaline battery including a plastic-bonded NiOOH active mass pressed onto a metallic substrate which has been previously coated with a layer of nickel dendrites to enhance the surface area of the substrate and promote adhesion of the active mass to the substrate.