Abstract: A system is disclosed that includes a detector and a combination of lenses and mirrors as imaging optics configured to provide for block by block compressive sensing of an imaged scene with the block by block determined by a plurality of shift-invariant masks to produce an image of the scene of the detector. A resolution of the image through the combination of lenses and mirrors is provided at the detector greater than a resolution capability of the detector at the detector. Another system and a method are also disclosed.

Abstract: An optical system is provided. The optical system includes a corrector lens that is configured to reduce aberrations in electromagnetic radiation (EMR) received from a window having a window axis of symmetry. A rotation mechanism is coupled to the corrector lens, and is configured to selectively rotate the corrector lens about an optical axis of the corrector lens to maintain a Y-axis of the corrector lens in a same plane as the window axis of symmetry of the window.

Abstract: An optical system is provided. The optical system includes a corrector lens that is configured to reduce aberrations in electromagnetic radiation (EMR) received from a window having a window axis of symmetry. A rotation mechanism is coupled to the corrector lens, and is configured to selectively rotate the corrector lens about an optical axis of the corrector lens to maintain a Y-axis of the corrector lens in a same plane as the window axis of symmetry of the window.

Abstract: A method is provided for characterizing emulsion stability to evaluate suitability of the emulsion for use as a drilling fluid in drilling subterranean boreholes. The method provides a supplement or alternative to the standard method of determining Electrical Stability of the emulsion. In the method of the invention, Breakdown Energy is calculated. Breakdown Energy can be measured at the same test point as Electrical Stability. A digital storage oscilloscope and a computer are used in addition to an electrical stability meter.

Abstract: A bias supply circuit and a method of operating a bias supply circuit for use with a switching power supply employing a main switch and an auxiliary switch and having an input voltage and a voltage across a clamp capacitor coupled to a transformer. In one embodiment, the bias supply circuit includes a bias supply winding associated with the transformer and configured to provide a first voltage dependent on at least one of the input voltage and the voltage across the clamp capacitor during a conduction period of the main switch or the auxiliary switch. Additionally, the bias supply circuit further includes a bias supply storage capacitor coupled to the bias supply winding and configured to provide a second voltage dependent on at least another of the input voltage and the voltage across the clamp capacitor during a conduction period of another of the main switch or the auxiliary switch. A sum of the first voltage and the second voltage provides a bias supply voltage.

Abstract: An apparatus and method for determining the crystallization point of high pressure fluids comprising brine are disclosed. The apparatus comprises a temperature probe and an optical fiber probe to determine the temperature of formation and dissolution of crystals during cooling and warming cycles. The apparatus further comprises a pressurization source, preferably a positive displacement pump or connection to a positive displacement pump for pressurizing the sample. The apparatus further preferably includes a jacket for circulating coolant or heat transfer fluid to facilitate cooling of the sample. The method of the invention uses the apparatus of the invention to determine crystallization point of fluid samples.

Abstract: An apparatus and method are disclosed for measuring or analyzing dynamic and static sag caused by settling of weighting materials in drilling fluids or other solids bearing fluid. The apparatus comprises a tube and shear shaft assembly that allows for a controlled rate of shear to be applied to a sample of the fluid for testing. During a test, the assembly is placed on a pivotal holder at an angle. The assembly has pistons at the pivot center of the assembly which accommodate expansion and contraction of the test fluid due to changes in temperature and pressure, thereby allowing the test fluid to be heated, cooled and pressurized to simulate subterranean wellbore conditions without changing the center of mass of the test fluid. When weight material settles down the inclined assembly, the center of mass of the assembly changes resulting in changing torque or moment about the pivotal holder. The resultant moment is measured by energizing external coils arranged to provide a uniform magnetic field.

Abstract: A method and apparatus for determining the effectiveness and reaction time of a breaker fluid in breaking a filter cake on the wall of a wellbore penetrating a subterranean formation is disclosed. The method comprises employing an apparatus, such as for example the apparatus of the invention with a filter medium and the capability of applying differential pressure or dynamic conditions to form a filter cake on the filter medium with drilling mud. Breaker fluid is then substituted for the drilling mud, preferably without damage to the filter cake. The quantity of breaker fluid passing across the filter medium under static conditions is monitored over time. An increase in the rate of fluid passing across or through the medium indicates break-up of the filter cake.

Abstract: A conventional fluid density balance beam measurement instrument used for measuring fluid density at atmospheric pressure is converted for use to measure fluid density at super-atmospheric pressure. The conversion is made without modifying the structure of the conventional instrument. A pressure lid, placed over the open mouth of the instrument's sample cup, is held in place by a removable retaining structure that wraps around the base of the cup. A screw ring at the top of the retainer applies a retaining pressure against the lid. Pressure is applied to the cup through a check valve stem extending through the lid. An adjustable flange on the rim of the lid permits the lid to advance into the cup to change the cup volume for sizing the cup to obtain a precisely known volume for measurement. A counterweight is removably connected to the balance beam to compensate for the weight added by the lid and retaining structure.

Abstract: A replaceable primary rupture disk placed in the main body of a cylindrical test chamber functions as a safety device and ruptures to relieve pressure from the chamber when the pressure exceeds a selected maximum value. A free piston that is moveable within the cylindrical to separate the chamber into two variable volume compartments is equipped with a replaceable secondary rupture disk that limits the pressure differential across the piston. The secondary disk ruptures at a pressure differential lower than that required to rupture the primary disk. The maximum pressure that can be contained in any chamber is a pressure equal to the sum of the secondary and primary rupture pressures. The maximum pressure that can be contained in one compartment, if the other is at atmospheric pressure, is the burst pressure of the secondary disk.

Abstract: A converter for enhancing power factor utilizes a line sense winding magnetically coupled to sense a voltage across a line inductor in the input of a high power factor power converter. This winding in the illustrative embodiment is typically a single turn. This winding provides a measurement of the derivative (with respect to time) of the line current, and a specially designed integrator connected to the winding provides the estimate of the line current. An integrator is operative to accurately estimate the current by using known properties of this current to prevent mismeasurement due to reconstructing the "constant of integration" and any small biases in the integrator which normally cause errors.

Abstract: The present invention is directed to an apparatus and method for holding one or more test electrodes of precisely known exposed surface area. The present invention is particularly useful in a device for determining the corrosion properties of the materials from which the test electrodes have been formed. The present invention relates to a device and method for holding the described electrodes wherein the exposed surface area of the electrodes is only infinitesimally decreased. Further, in the present invention the exposed, electrically conductive surface area of the contact devices is small relative to the test electrode surface area. The holder of the present invention conveniently comprises a device for contacting and engaging each test electrode at two point contacts infinitesimally small in relation to the exposed surface area of the electrodes.

Abstract: The present invention is directed to an apparatus and method for measuring the viscosity of a fluid. This apparatus and method is particularly useful for the measurement of the viscosity of a liquid in a harsh environment characterized by high temperature and the presence of corrosive or deleterious gases and vapors which adversely affect conventional ball or roller bearings. The apparatus and method of the present invention employ one or more flexural or torsional bearings to suspend a bob capable of limited angular motion within a rotatable sleeve suspended from a stationary frame.

Abstract: The present invention is directed to an apparatus and method for preventing diffusion of a gas under high pressure into the bulk of a liquid filling a substantially closed chamber. This apparatus and method is particularly useful in connection with test devices for testing fluid characteristics under harsh conditions of extremely high pressure and high temperature. These devices typically pressurize the liquid by placing the liquid in pressure and fluid communication with a high pressure inert gas. The apparatus and method of the present invention prevent diffusion of the pressurizing gas into the bulk of the test liquid by decreasing the chamber volume at a rate sufficient to maintain the bulk of the liquid free of absorbed or dissolved gas by expelling that portion of the liquid which is contaminated by the pressurizing gas.

Abstract: Concentric cylinder viscometer comprising means for rotating an outer sleeve which exerts a viscous drag on an inner cylinder, the torque of which is registered by spring means, and in which the outer sleeve is rotated at any of several pre-selected speeds by a direct current motor, the speed of which is controlled by a phase-locked feedback circuit in which the instantaneous speed of the motor is detected by an incremental encoder, the signal from which is fed to a digital display showing the rotational speed and is also fed back to the phase-locked comparator circuit which causes the application to the motor of the voltage required to drive it at the desired speed. The circuit includes an oscillator and frequency dividers which provide a plurality of precisely controlled frequencies, and also includes a variable oscillator which provides any desired hand-settable frequency over a wide range. The device is particularly adapted to the testing of drilling fluids.