Abstract: An underwater vibrator apparatus for generating a shear wave into the consolidated seabed has a housing, a horizontally mounted mass attached to said housing for movement along an axis substantially parallel to the surface of the earth and hydraulic apparatus for oscillating the mass along the axis. Substantially all of the vibrator housing comprises a sidewall and a bottom. The sidewalls and bottom form a wedge-shaped surface means with an angled surface of the wedge-shaped surface transverse to the movement of the mass, such that as the mass oscillates the underwater vibrator against the consolidated bottom, the vibrator will settle into the bottom. The vibrator will, however, maintain contact with the bottom even when the consolidated bottom is yieldable under vibrated weight.

Abstract: A machine process for identification and extraction of magnitude and direction of edges and lines in noisy multidimensional imagery data. A digital picture function is viewed as a sampling of the underlying reflectance function of the objects in the scene or pattern with noise added to the true function values. The edges or lines relate to those places in the image where there are jumps in the values of the reflectance function or its derivatives. By expressing the function in some parametric form in the local neighborhood of the pixel under consideration, the edges or lines and the types of edges (left to right or right to left) or lines (peak to trough) may be inferred from the values of the parameters. Assuming the noise is Gaussian, significant edges or lines are detected by performing the statistical hypothesis tests on the parameters of the function. Recursive relations are used for efficiently estimating the parameters of the function.

Abstract: An apparatus for incremental cylinder length control in a hydraulic vibrator of the type having a reaction mass with a cylinder bore disposed therein, first and second end sleeves disposed in sealed movable position in the ends of the cylinder, a piston rod sealed and slidably disposed through the first and second sleeves with a piston attached to the piston rods where the improvement comprises threading the ends of the cylinder bore and forming mating threads on the first and second sleeves with means for rotating the sleeves with respect to the cylinder so that the sleeves move toward or away from the piston thereby reducing the volume of hydraulic oil between the end of the piston and the end sleeves.

Abstract: An apparatus includes a logging tool having electrodes for introducing a current into a downhole formation and for detecting a voltage produced in the formation by the current. The current is provided by a transmitter circuit, and the voltage is received and processed by a receiver circuit including a computer programmed to provide induced polarization and resistivity measurements based on the detected voltage. The electrodes are equidistantly spaced but are adjustable (either on a single logging tool or as between different logging tools) so that various logging runs can be made to obtain different measurements whereby the intrinsic complex resistivity (induced polarization) of formation layers can be suitably resolved. The apparatus also includes a contact resistance measurement circuit for making measurements used by another computer means to determine the contact resistance of each of the electrodes.

Abstract: A method for developing a novel seismic data attribute enables improvements in seismic data processing and interpretation. Seismic signals or trace data are first rectified and then Hilbert transformed and processed with the arc tangent function to develop a new instantaneous phase parameter referred to as phase of rectified trace (PORT). Output data may be further enhanced with tri-modal, interactive color display.

Abstract: A computer implemented method for representation and recognition of waveforms uses information derived from several groups of such waveforms of general similarity. Each signal is considered as an additive combination of the common signal of the respective group and a noise term. The common signals of the groups of waveforms are extracted using a set of data-derived orthonormal basis waveforms, and a criterion is developed to evaluate the combination of individual basis waveforms used for the common signal extraction. The estimated common signals then represent a template pattern of the waveform or signal groups that can be used in waveform recognition.

Abstract: Method for automated hydro-blast de-coking of delayed coke drums wherein programmed central control receives input of drill stem tension, drill bit elevation and drill stem rotation along with indications as to hydraulic hoist power and air pressure input to the drill stem rotary motor, and functions to provide control outputs to automatically control the pilot and main bed cutting procedures attendant an entire drum de-coking operation.

Abstract: Method and apparatus for high accuracy simultaneous calibration of electrical measuring systems wherein a calibration signal which has frequency spectra which interleave but do not interfere with the data spectra is injected into the electrical system during data acquisition to simultaneously correct for the response of the particular detection system. In a particular geophysical application, a calibration signal at a source system or receiver system, or both, is injected into each individual system as the data and calibration signals are measured so that an overall system response can be applied to the data signals in order to remove system response effects therefrom.

Abstract: An encode-decoder system for generating highly accurate, coinciding synchronizing signals at each of plural separated locations; for example, a system generating start signals for a seismic data acquisition system. The system transmits psuedo random code data over selected communication link to a respective position decoder which samples the incoming code and compares it with a standard code. If there can be established a predetermined number of successive code matches, an output start signal is enabled when the code match count first peaks and then decreases.

Abstract: A source of linearly polarized light having a wavelength selected from the range of about 500 to 1100 nanometers provides light into one end of an optical fiber. A nonlinear crystal of the type that mixes the frequency of light passing therethrough is positioned adjacent the other end of the fiber. The fiber transmits light from the source to the crystal which increases its frequency up to 100%, dependent upon crystal selection, thereby providing light in the 250-550 nanometer wavelength range. Adjusting the radial orientation of the crystal with respect to the fiber optimizes conversion of light to the 250-550 nanometer range.

Abstract: A process for better defining first break seismic energy travel times for correlated seismic return signals that consists of constructing a minimum phase bandpass filter having bandwidth narrower than the vibrational seismic return signals and convolving the filter with the return signals to convert the seismic return signals to a causal wave form.

Abstract: A demodulation circuit comprising a high-frequency amplifier (2) and a subsequent demodulator (3) the output of which is fedback to a control input of the amplifier (2) via a keyed automatic gain control circuit (5). In addition, the output is fedback to a carrier input of the demodulator (3) via a phase control circuit (11) and a phase shifter (8) to which a reference carrier (CS) is applied. The phase control circuit (11) is supplied with a pulse-shaped signal (VBS) having periodic pulses. The pulses are directly conveyed to the phase shifter (8) and they further switch a gate circuit (19-23) by means of which the demodulator output is connected to an integrating differential amplifier (26) the output of which is coupled to the phase shifter (8).

Abstract: An FM-receiver having an FM-channel successively comprising an RF-input stage and mixer stage (B), an IF-circuit (A) and a ratio detector (R). The ratio detector incorporates silicon detector diodes and a smoothing capacitor conductively connected to the detector diodes for a dynamic amplitude limitation of the ratio detector output signal in dependence on the amplitude of the ratio detector input signal. A bias voltage is applied to the silicon diodes to prevent the silicon diodes from being blocked at signals lower than the threshold voltage of the diodes. The bias voltage comprises an average noise voltage that is generated by amplifying a noise component of the FM signal, the noise component being present in the IF bandwidth. The average noise voltage is predominantly obtained by amplifying the noise produced within the IF-passband of the IF-input stage.

Abstract: An interface for subscription television reception which restores the program selection function to the tuner of the television receiver. This is of particular importance to subscribers using remote control receivers. Subscription television signals are split into two substantially identical components, one of which is fed to the tuner of the television receiver and the other of which is passed through a band reject filter to an adder. The intermediate frequency output of the tuner is converted to a predetermined carrier frequency in the television broadcast band and, as so converted, fed to the other input of the adder. The output of the adder is, in turn, fed to a conventional subscription television converter/decoder, which is set to select the program on the predetermined carrier frequency and decode the same. The converter/decoder output is converted to the intermediate frequency carrier for amplification and further processing in the intermediate frequency circuitry of the television receiver.

Abstract: An FM broadcasting system comprises an FM transmitter for transmitting a multiplex signal which is frequency-modulated on a main carrier wave and an FM receiver for cooperation with said FM transmitter. The multiplex signal comprises: an audio-frequency first information signal and, in the case of a stereo transmission, a second information signal modulated on a suppressed stereo subcarrier, a stereo pilot signal whose frequency (f.sub.p) is situated between the frequency spectra of the two information signals, a first binary-code signal (f.sub.p -f.sub.c) which is phase-modulated on a first code subcarrier situated outside the frequency spectra, which code subcarrier is a harmonic of a subharmonic of the stereo pilot (f.sub.p) which harmonic does not coincide with a harmonic of said pilot (f.sub.p), the multiplex signal, in order to extend the transmission capacity, comprising a second binary-code signal which is phase-modulated on a second code subcarrier (f.sub.p +f.sub.c).

Abstract: FM-receiver comprising an aerial input having connected thereto, in succession, an RF input stage, an IF portion, an FM-detector and a stereo decoder having a mono-stereo control circuit therein, also a control signal generating circuit being connected thereto, the control signal generating circuit comprising a multipath reception detector and being connected to the IF portion via a level detector, the multipath reception detector comprising an amplitude detector connected to the level detector via a bandpass filter. The FM-receiver also comprises a noise pulse suppression circuit arranged between the FM-detector and the stereo decoder for keeping the amplitude of the stereo multiplex signal constant during the occurrence of noise pulses.

Abstract: Signal comparison arrangement for comparing a first and a second analog signal with each other. For each of these signals the number of zero-crossings occurring within each measuring interval of a sequence of N consecutive measuring intervals T(1), T(2), . . . T(N) is counted. The N numbers x(1), x(2), . . . x(N) which represent the numbers of zero-crossings of the first analog signal in the consecutive measuring intervals T(1), T(2), . . . T(N) and the N numbers y(1), y(2), . . . y(N) which represent these numbers of zero-crossings of the second analog signal in the said measuring intervals, are applied to a programmable computer which determines the value of a statistical quantity by means of these 2N numbers and compares this value with a threshold value. This statistical quantity may be formed by the directional coefficient of a straight line which is closest to either the N numbers x(n), or the N numbers y(n), but may alternatively be formed by the correlation coefficient.

Abstract: FM-broadcasting system comprising a FM-transmitter (1-16, 32-34) and a receiver (14-31, 35, 36) cooperating therewith, the transmission signal of which comprises a multiplex signal which is frequency-modulated on a main carrier wave, which multiplex signal comprises an audio-frequency information signal (L+R) and, in the case of a stereo transmission, a stereo information signal (L-R) modulated on a (38 kC) suppressed stereo subcarrier wave, also comprising a (19 kC) stereo pilot which is situated between the frequency spectra of the two information signals and a binary, differentially coded code signal which is phase-modulated on a (16.625 kC) code subcarrier wave which is situated outside the frequency spectra, and does not coincide with the (19 kC) stereo pilot, the receiver (14-31, 35, 36) comprising a pilot regeneration circuit (22-25) for regenerating the (19 kC) stereo pilot, the code signal having a bit repetition period which is an integral number of times the period of the (19 kC) stereo pilot.

Abstract: A television camera in which an electronic view-finder is further used for adjusting an optimum focusing. The picture signal is then applied to the view-finder via a switching device, and that during the presence of an aperture correction signal. Outside the occurrence of this aperture correction signal the supply of a picture signal which has been made unsharp may be affected, or the supply thereof may be interrupted. Adjusting the optimum focusing on the basis of the picture on the viewer screen is then facilitated.

Abstract: NTSC-color television coding circuit comprising a series arrangement formed by a color difference signal matrix circuit, an I-signal and Q-signal matrix circuit, two low-pass filters, a modulator circuit and a superposition stage for supplying a quadrature-modulated chrominance signal. In order to obtain the chrominance sub-carrier burst in the chrominance signal, a burst-gate signal the pulse leading edge of which is produced before the beginning of the burst, is added to the -(B-Y) color difference signal. The chrominance signal in which the prolonged burst is distorted at the beginning by the filter is applied to a signal blanking circuit in which the distorted beginning is blanked and the burst in accordance with the standard is present in the chrominance signal obtained. Now, the burst amplitude can be adjusted, without a phase shift, by means of one potentiometer.