Abstract: A cleaning robot may determine a three-dimensional model of a physical environment based on data collected from one or more sensors. The cleaning robot may then identify a surface within the physical environment to clean. Having identified that surface, the robot may autonomously navigate to a location proximate to the surface, position an ultraviolet light source in proximity to the surface, and activate the ultraviolet light source for a period of time.

Abstract: The invention provides for metering the pumping rate of BFS/mud mixtures pumped to the cementing head on a rig for sealing off the formation from the casing. Since BFS/mud mixtures require an activation agent, preferably sodium hydroxide is pumped into the flowline to the cementing head. Feedback from the BFS/mud slurry flowrate is fed to the activator injector pump drive system to regulate the addition rate of the activating agent in response to varying conditions, such as mud flowrate. The injection rate target can also be adjusted to compensate for any changes in downhole temperature. The risk of fouling surface equipment and the casing internal diameter is minimized because the activation agent is added very close in time to when the BFS/mud mixture enters the cementing head.

Abstract: A method for monitoring the location and set of a cement slurry within a support member of an offshore structure is disclosed. The location and setting properties of the cement are determined by monitoring the electrical resistivity of the fluid within the support member. Preferably, a plurality of electrical probes mounted along the length of the support member can be used to measure the electrical resistivity of fluid within the member. Normally, the presence of cement would be indicated by an abrupt change of resistivity as the cement displaces the original fluid (air or sea water) present in the support member. Resistivity of the cement slurry will also change gradually as the cement sets.

Abstract: The present invention is concerned with a ribbon for non-impact printing. The ribbon comprises a transfer coating and a substrate which is a polycarbonate resin containing from about 15% to about 40% by weight of electrically conductive carbon black.

Abstract: A cement composition suitable for cementing high temperature wells comprises dry cement grains coated with a tenacious film of a crosslinked hydroxyalkyl cellulose. The film resists high temperature hydrolysis and is effective to retard the setting of the cement in high temperature environments. The method of preparing the composition involves coating the dry cement grains, preferably by a microencapsulation process, with the crosslinked hydroxyalkyl cellulose film. The cement composition is particularly useful in cementing pipe strings in wells.

Abstract: A self regulating telephone apparatus wherein an individual's speech is converted to a representative electrical signal. This signal is represented by a product wave or waves of the form f(A)t x f(B)t where f(A)t represents the amplitude of the informational signal f(B)t. The signal is separated by demodulation of the cross product into its components. The relative amplitudes of the terms are changed as desired and the cross product re-established by remodulation. Since the term f(A)t represents the amplitude and its frequency range is removed from f(B)t, amplification can be provided at frequencies exhibiting low coupling between the receiver and transmitter transducer in a hand telephone set to permit increasing the signal volume output as required.

Abstract: A four-wire interface regulator for long distance trunk circuits is provided in which the interface regulator separates the components of a conventional local plant output signal to change the relative magnitude of the components to deliver any desired output with a minimum variability to drive long distance trunk circuits.