An optically based combustion off-gas stream velocity sensor assembly is provided for detecting in real-time off-gas flow velocity and/or volume as it moves through a flue duct. The sensor assembly includes two paired coherent light emitters and optic sensors, positioned in a spaced orientation in the flow path direction. The light emitter/optic sensor pairs operate to emit and detect across the off-gas stream coherent light beam energy having a wavelength component corresponding to an absorption profile of an off-gas species component. The detection of non-absorbed portions of the emitted beam is used to identify and detect the movement of a flow species signature at different locations along the flue duct.

A scatterer measurement method includes: radiating a first irradiating light that passes through a first space in which a scatterer is present; receiving a first scattered light produced by the first irradiating light being scattered by the scatterer; after the scatterer has moved from the first space to a second space at least partially different from the first space, radiating a second irradiating light that passes through the second space; receiving a second scattered light produced by the second irradiating light being scattered by the scatterer; and calculating a velocity of the scatterer based on a difference between a first point in time at which the first scattered light was received and a second point in time at which the second scattered light was received and a distance that the scatterer moved during a period from the first point in time to the second point in time.

An underwater detector includes a sealed enclosure, inside an infrared sensor module is disposed. The module rotates around a spindle at a fixed angular velocity along a horizontal plane. An electronic compass disposed on the module. A bottom of the sealed enclosure connected to an indicator through a rotary shaft, and the indicator rotates around the rotary shaft on the horizontal plane. The indicator includes a head and tail fin. A light source emits a light beam vertically upwards on the tail fin. The module is configured to trigger, when receiving the light beam, the electronic compass records a real-time direction relative to the spindle, which is processed by a processor module to obtain a direction of the water flow. A spring connects between the head and tail fin. The infrared sensor module transmits a moment of receiving the light beam to the processor module to calculate the water flow.

A lighter-than-air (LTA) vehicle navigation system and vehicle. The navigation system includes a first wind probing device disposed at a first probe position, wherein the first wind probing device is in communication, via a first probe communications link, with a body communication system. The navigation system also includes a second wind probing device disposed at a second probe position, wherein the second wind probing device is in communication, via a second probe communications link, with the body communication system. The navigation system also includes a wind variation detection system configured to determine wind information, including at least a wind direction, for the first wind probing device and the second wind probing device.

A method (400) for identifying precipitation (50) includes the steps of: providing (410) a lighting unit (10) having a first photosensor (32), a second photosensor (34), and a controller (22), where the first and second photosensors are vertically spaced by a first distance; receiving (430), by the first photosensor, a first light signal from the precipitation at a first time point (T1); receiving (440) by the second photosensor, a second light signal from the precipitation at a second time point (T2); calculating (450) the amount of time between the first light signal and the second light signal; and calculating (460), based on the first distance and the calculated amount of time between the first light signal and the second light signal, a velocity of the precipitation.

An apparatus and method for determining fluid flow (e.g., sterile media flow, filtrate flow, etc.) through tubing is provided. The apparatus includes an air source, a flow valve, a first sensor, a second sensor, and a media tubing section extending between the first sensor and the second sensor. In operation, air from the air source is introduced by the flow valve into a fluid flow to create a lead line of fluid immediately following the introduced air. As the lead line of fluid passes each sensor, the sensors are used to determine a time between when the lead line passes the first sensor and the second sensor and that determined elapsed time is used, along with a determined volume of the media tubing section to determine the rate of flow of the fluid flow.

An apparatus and method for determining fluid flow (e.g., sterile media flow, filtrate flow, etc.) through tubing is provided. The apparatus includes an air source, a flow valve, a first sensor, a second sensor, and a media tubing section extending between the first sensor and the second sensor. In operation, air from the air source is introduced by the flow valve into a fluid flow to create a lead line of fluid immediately following the introduced air. As the lead line of fluid passes each sensor, the sensors are used to determine a time between when the lead line passes the first sensor and the second sensor and that determined elapsed time is used, along with a determined volume of the media tubing section to determine the rate of flow of the fluid flow.

An apparatus for measuring fluid speed by using the refraction of light is disclosed. The apparatus includes: a channel in which a passage is formed to allow the flow of a fluid; a first and a second light source that are located in any one region of an upper part and a lower part of the channel; a sensor installed in an opposite region of the region where the first and second light sources are located with respect to the channel, to receive the light emitted from the first and second light sources; a speed calculation unit that calculates the speed of the fluid by using a time point at which the intensity of the light received at the sensor changes; and an adjustment unit that is connected to the channel and configured to adjust the flow speed of the fluid based on the calculated speed of the fluid.

An apparatus for measuring fluid speed by using the refraction of light is disclosed. The apparatus includes: a channel in which a passage is formed to allow the flow of a fluid; a first and a second light source that are located in any one region of an upper part and a lower part of the channel; a sensor installed in an opposite region of the region where the first and second light sources are located with respect to the channel, to receive the light emitted from the first and second light sources; a speed calculation unit that calculates the speed of the fluid by using a time point at which the intensity of the light received at the sensor changes; and an adjustment unit that is connected to the channel and configured to adjust the flow speed of the fluid based on the calculated speed of the fluid.

A lighter-than-air (LTA) vehicle navigation system and vehicle. The navigation system includes a first wind probing device disposed at a first probe position, wherein the first wind probing device is in communication, via a first probe communications link, with a body communication system. The navigation system also includes a second wind probing device disposed at a second probe position, wherein the second wind probing device is in communication, via a second probe communications link, with the body communication system. The navigation system also includes a wind variation detection system configured to determine wind information, including at least a wind direction, for the first wind probing device and the second wind probing device.