Abstract: A diesel fuel and additive mixture is useful for reducing particulate matter emissions while improving or at least not aggravating oxidative stability during combustion. The additive includes at least one compound having a general formula selected from the group consisting of: and combinations thereof, wherein: R is a saturated or unsaturated hydrocarbon having from about 1 to about 6 carbons. The additive is effective in diesel at concentrations as low as from about 50 to about 1000 ppm by weight.

Abstract: A diesel fuel and additive mixture is useful for reducing particulate matter emissions while improving or at least not aggravating oxidative stability during combustion. The additive includes at least one compound having a general formula selected from the group consisting of: and combinations thereof, wherein: R is a saturated or unsaturated hydrocarbon having from about 1 to about 6 carbons. The additive is effective in diesel at concentrations as low as from about 50 to about 1000 ppm by weight.

Abstract: A method, which allows, in an acoustic pulse-echo ranging system, the direct use of a digitized raw echo signal for correlation-based echo distance estimation, where an acoustic pulse having a carrier frequency is transmitted, a digital expected echo shape is provided with a time resolution higher than the carrier frequency, an echo is received from the acoustic pulse, the received echo is sampled and digitized at a sampling frequency higher than the carrier frequency, correlation values are created from the digitized received echo and the digital expected echo shape, the correlation values are weighted by emphasizing stronger correlation values, and the echo distance is determined from the center of mass of the weighted values.

Abstract: A method, which allows, in an acoustic pulse-echo ranging system, the direct use of a digitized raw echo signal for correlation-based echo distance estimation, where an acoustic pulse having a carrier frequency is transmitted, a digital expected echo shape is provided with a time resolution higher than the carrier frequency, an echo is received from the acoustic pulse, the received echo is sampled and digitized at a sampling frequency higher than the carrier frequency, correlation values are created from the digitized received echo and the digital expected echo shape, the correlation values are weighted by emphasizing stronger correlation values, and the echo distance is determined from the center of mass of the weighted values.

Abstract: A level measurement or time of flight ranging apparatus for determining a distance measurement to the surface of a material. The apparatus comprises a transducer, a transmitter, a receiver and a processor. In response to the transmitter, the transducer emits energy pulses towards the surface of the material. The transducer detects pulses reflected by the material surface and the receiver converts the reflected pulses into signals for further processing by the processor. The apparatus further includes a mechanism for reflecting a reference pulse from a known distance with respect to the transducer. The processor determines a ratio between the reference distance (or reference pulse time of travel) and the reflected pulse(s) (or reflected pulse time of travel). The ratio is used with the reference distance to determine the distance measurement to the surface of the material.