Abstract: Organocatalysts can be engineered to mimic biological enzymes for use in a variety of industrially relevant chemical reactions. The organocatalyst comprises a chemical catalyst that is made by imidation of an amine-containing compound to form an N-substituted maleimide and appending the N-substituted maleimide on a furan-containing compound by Diels-Alder reaction and hydrogenation. The N-substituted maleimide may also be made by reacting a protected maleimide and compound containing a primary alkyl halide moiety. The organocatalysts are engineered to append chemical functionalities of amino acids such as glutamic acid for catalyzing hydrolysis of lactose. The organocatalyst further comprises a support to immobilize the chemical catalyst which plays the role of a scaffold to stabilize catalytic active sites and bind the reactants nearby the active sites, similar to a protein scaffold in biological catalysts.

Abstract: A system comprises a computer including a processor and a memory. The memory includes instructions such that the processor is programmed to: execute an autonomous vehicle algorithm simulating vehicle operations within a simulated environment. The simulated environment represents a plurality of driving situations. The memory also includes instructions such that the processor is programmed to: determine a challenge rating for the driving situation, determine an autonomous vehicle performance assessment score corresponding to the simulated environment, compare the autonomous vehicle performance assessment score with a human driving score corresponding to the simulated environment, and generate a performance profile based on the comparison. In some implementations, a vehicle computer can determine a challenge rating and generate at least one of a driver takeover recommendation or an alert indicating a presence of a fault based on a comparison of vehicle performance with the challenge rating.

Abstract: A system comprises a computer including a processor and a memory. The memory includes instructions such that the processor is programmed to: receive sensor data representing a perceived driving environment, select a reinforcement learning agent from a plurality of reinforcement learning agents based on a challenge score calculated using the sensor data and a desired driving style, and generate, via the selected reinforcement learning agent, a driving action based on the sensor data.

Abstract: Apparatuses and methods train a model and then use the trained model to determine a global three dimensional (3D) position and orientation of a fiduciary marker. In the context of an apparatus for training a model, a wider field-of-view sensor is configured to acquire a static image of a space in which the fiducial marker is disposed and a narrower field-of-view sensor is configured to acquire a plurality of images of at least a portion of the fiducial marker. The apparatus also includes a pan-tilt unit configured to controllably alter pan and tilt angles of the narrower field-of-view sensor during image acquisition. The apparatus further includes a control system configured to determine a transformation of position and orientation information determined from the images acquired by the narrower field-of-view sensor to a coordinate system for the space for which the static image is acquired by the wider field-of-view sensor.

Abstract: A switching digital-to-analog converter (DAC) includes a logic gate for receiving a digital input signal having rising and falling edges defining an input pulse width, and outputting an offset input signal having rising and falling edges defining a mismatched pulse width different from the input pulse width due to relative movement of the rising and falling edges in response to a voltage offset introduced by the logic gate. A DC voltage source provides a direct current (DC) calibration signal, and a summer adds the DC calibration signal and the offset input signal to compensate for the voltage offset introduced by the logic gate, and to provide a corrected input signal. A unit DAC receives the corrected input signal, and selectively switches current to an output of the switching DAC in response to voltage values of the corrected input signal to provide an analog output.

Abstract: A tip-weighted drumstick with a cushioned sleeve that absorbs shock and protects a drummer's hands and other joints while playing. The cushioned sleeve covers a reduced-diameter portion of the drumstick and can be customized with various surface textures, shapes, and other features. The reduced-diameter portion may result in the center of gravity of the drumstick shifting towards the striking end of the drumstick to improve the efficiency and effectiveness of the drumstick.

Abstract: The present disclosure provides a control system for a machine having a transmission. The control system includes an open gate shift pattern having a plurality of defined positions disposed within an outer perimeter. Each of the defined positions corresponds to one of a plurality of forward and reverse ranges of the transmission. A control lever is movably disposed within the shift pattern. A first set of defined positions is aligned in the shift pattern corresponding to the plurality of forward ranges and a second set of defined positions is aligned in the shift pattern corresponding to the plurality of reverse ranges. The control lever is moveable in a single movement to any of the plurality of defined positions for selecting between a forward range and reverse range.

Abstract: A tip-weighted drumstick with a cushioned sleeve that absorbs shock and protects a drummer's hands and other joints while playing. The cushioned sleeve covers a reduced-diameter portion of the drumstick and can be customized with various surface textures, shapes, and other features. The reduced-diameter portion may result in the center of gravity of the drumstick shifting towards the striking end of the drumstick to improve the efficiency and effectiveness of the drumstick.

Abstract: A mud pulser tool to be positioned into a downhole environment is disclosed. The mud pulser tool includes a control valve that is selectively opened to allow fluid to flow through the mud pulser tool or selectively closed to restrict the fluid flow, wherein the control valve is selectively opened or closed to produce a mud pulse signal transmitted through the fluid. The mud pulser tool also includes a sensor system to measure a pressure drop across the control valve. In one example, the mud pulser tool includes a control system to selectively open or close the control valve to adjust the pressure drop to produce a selected pressure drop across the control valve.

Abstract: In an embodiment, a correlation SONAR system is adapted for use in shallow water. A pulse generator transmits an initial burst of pulses towards a bottom of a body of water. Echoes of the initial burst of pulses are received on a hydrophone array. After the receiving the echoes of the initial burst of pulses, a second burst of pulses is transmitted towards the bottom of the body of water. The echoes of the second burst of pulses are received on the hydrophone array, and a SONAR processor correlates a pulse from the initial burst of pulses and a pulse from the second burst of pulses to calculate a velocity estimate.

Abstract: In an embodiment, a process measures a velocity of a vessel using a spatial correlation sonar hydrophone array. The process includes the step of selecting a correlation time such that a correlation occurs between an early pulse and a later pulse on a first hydrophone and a second hydrophone respectively, wherein the first hydrophone and the second hydrophone are maximally separated in the spatial correlation sonar hydrophone array. The process further includes the step of selecting a time spacing between a first pulse and a second pulse such that the spacing is a function of the correlation time and a constant, wherein the constant is proportional to a size of the spatial correlation sonar hydrophone array, and wherein the correlation time is an approximate multiple of a sum of a time between the first pulse and the second pulse and a time between the second pulse and a next first pulse.

Abstract: In an embodiment, a correlation SONAR system is adapted for use in shallow water. A pulse generator transmits an initial burst of pulses towards a bottom of a body of water. Echoes of the initial burst of pulses are received on a hydrophone array. After the receiving the echoes of the initial burst of pulses, a second burst of pulses is transmitted towards the bottom of the body of water. The echoes of the second burst of pulses are received on the hydrophone array, and a SONAR processor correlates a pulse from the initial burst of pulses and a pulse from the second burst of pulses to calculate a velocity estimate.

Abstract: A mud pulser tool to be positioned into a downhole environment is disclosed. The mud pulser tool includes a control valve that is selectively opened to allow fluid to flow through the mud pulser tool or selectively closed to restrict the fluid flow, wherein the control valve is selectively opened or closed to produce a mud pulse signal transmitted through the fluid. The mud pulser tool also includes a sensor system to measure a pressure drop across the control valve. In one example, the mud pulser tool includes a control system to selectively open or close the control valve to adjust the pressure drop to produce a selected pressure drop across the control valve.

Abstract: In an embodiment, a process measures a velocity of a vessel using a spatial correlation sonar hydrophone array. The process includes the step of selecting a correlation time such that a correlation occurs between an early pulse and a later pulse on a first hydrophone and a second hydrophone respectively, wherein the first hydrophone and the second hydrophone are maximally separated in the spatial correlation sonar hydrophone array. The process further includes the step of selecting a time spacing between a first pulse and a second pulse such that the spacing is a function of the correlation time and a constant, wherein the constant is proportional to a size of the spatial correlation sonar hydrophone array, and wherein the correlation time is an approximate multiple of a sum of a time between the first pulse and the second pulse and a time between the second pulse and a next first pulse.

Abstract: A method of estimating velocity with a correlation SONAR that provides an improved velocity estimate due to a reduction in random and bias errors is disclosed. The method generates a velocity estimate based on a weighted average of pulse-pairs that includes processing of those pulse-pairs based on an optimal correlation time as well as pulse-pairs based on sub-optimal correlation times.

Abstract: A correlation SONAR that provides improved velocity estimates due to a reduction in random and bias errors is disclosed. Rather than basing the velocity estimate on a single set of primary receiver pairs, one or more additional velocity estimates are generated based on one or more available receiver pair sets having the same velocity vectors as the primary receiver pairs set. Additional velocity estimates also provide a reliability and accuracy improvement by enabling identification and subsequent elimination of erroneous velocity estimates.

Abstract: A sonar system comprises a transmitter adapted to provide pulse sequences, wherein each of the pulse sequences includes pulses that reflect off an object, a receiver adapted to receive the reflected pulses, and a processor. The processor is configured to transmit a first pulse sequence via the transmitter to obtain a first distance to the object in a first distance range and to transmit a second pulse sequence via the transmitter to obtain a second distance to the object in a second distance range. The processor is configured to transmit the second pulse sequence in response to being unable to obtain the first distance to the object in the first distance range.

Abstract: A method and apparatus for achieving etch rate uniformity in a reactive ion etcher. The reactive ion etcher generates a plasma within a vacuum chamber for etching a substrate disposed at a cathode of a reactor can within the chamber wherein the plasma emanates from a top plate of the reactor can, and is influenced by localized magnetic fields for locally controlling etch rates across the cathode to produce a uniform etch rate distribution across the cathode as a result of the localized magnetic field. The magnet array may be disposed between the top plate and the vacuum chamber for providing the localized magnetic fields. The magnet array includes a plurality of individual magnets and a grid plate for holding the individual magnets in position.