A method of mounting a rail monitoring member/element at a mounting location of a rail for rail traffic, in particular on a railway track, is disclosed. The rail monitoring member includes a strain sensor member with a carrier on which a strain gauge, being an optical fiber with a fiber Bragg grating, is fixed. The method steps include: determination of the temperature of the rail and/or rail monitoring member at the mounting location; checking whether the determined temperature is within a predefined temperature interval; providing heating or cooling application to the rail and/or rail monitoring member at the mounting location, if the determined temperature is not within the predefined temperature interval; positioning and adhesively fixing of the carrier of the rail monitoring member at the mounting location. The method can be carried out easily and allows reliable and accurate monitoring of the rail using a strain sensor member.

Systems and methods consistent with the present disclosure may position a cementing tool within a casing string of a wellbore. Such a system may include a fiber optic cable coupled to the cementing tool and may include a distributed temperature sensing (DTS) system interrogator positionable at a surface of the wellbore for transmitting an optical signal through the fiber optic cable such that a plurality of temperatures along the fiber optic cable may be identified. A reel may be used when dispensing the fiber optic cable from a first end of the fiber optic cable in response to a tension in the fiber optic cable as the cementing tool travels down the casing string behind a cement composition. A processor in communication with the DTS system may be configured to monitor the plurality of temperatures along the fiber optic cable while the cement composition cures.

Systems and methods consistent with the present disclosure may position a cementing tool within a casing string of a wellbore. Such a system may include a fiber optic cable coupled to the cementing tool and may include a distributed temperature sensing (DTS) system interrogator positionable at a surface of the wellbore for transmitting an optical signal through the fiber optic cable such that a plurality of temperatures along the fiber optic cable may be identified. A reel may be used when dispensing the fiber optic cable from a first end of the fiber optic cable in response to a tension in the fiber optic cable as the cementing tool travels down the casing string behind a cement composition. A processor in communication with the DTS system may be configured to monitor the plurality of temperatures along the fiber optic cable while the cement composition cures.

A microstructured optical fiber sensor for sensing changes in a physical characteristic up to a predetermined temperature is disclosed. The sensor includes a microstructured optical fiber and a fiber Bragg grating formed in the microstructured optical fiber by generating a periodic modulation in the refractive index along a core region of the suspended core. The fiber Bragg grating is configured to produce a band reflection spectra including a fundamental mode and a plurality of higher order modes whose respective wavelengths vary in accordance with changes in the physical characteristic at the core region of the microstructured optical fiber. The microstructured optical fiber is configured to increase the confinement loss of the plurality of higher order modes of the band reflection spectra relative to the fundamental mode.

A microstructured optical fiber sensor for sensing changes in a physical characteristic up to a predetermined temperature is disclosed. The sensor includes a microstructured optical fiber and a fiber Bragg grating formed in the microstructured optical fiber by generating a periodic modulation in the refractive index along a core region of the suspended core. The fiber Bragg grating is configured to produce a band reflection spectra including a fundamental mode and a plurality of higher order modes whose respective wavelengths vary in accordance with changes in the physical characteristic at the core region of the microstructured optical fiber. The microstructured optical fiber is configured to increase the confinement loss of the plurality of higher order modes of the band reflection spectra relative to the fundamental mode.

Described are a two-dimensional wind-speed and wind-direction sensor and a system thereof, relating to the field of sensing devices. The two-dimensional wind-speed and wind-direction sensor includes: an X-direction wind speed probe assembly and a Y-direction wind speed probe assembly, the X-direction wind speed probe assembly and the Y-direction wind speed probe assembly are perpendicular to each other, and the X-direction wind speed probe assembly is configured to measure a X-direction wind speed including a wind speed in the reverse direction of an X-axis, Vx−, and a wind speed in the forward direction of the X-axis Vx+; and the Y-direction wind speed probe assembly is configured to measure a Y-direction wind speed including a wind speed in reverse direction of an Y-axis, Vy−, and a wind speed in the forward direction of the Y-axis, Vy+.

Described are a two-dimensional wind-speed and wind-direction sensor and a system thereof, relating to the field of sensing devices. The two-dimensional wind-speed and wind-direction sensor includes: an X-direction wind speed probe assembly and a Y-direction wind speed probe assembly, the X-direction wind speed probe assembly and the Y-direction wind speed probe assembly are perpendicular to each other, and the X-direction wind speed probe assembly is configured to measure a X-direction wind speed including a wind speed in the reverse direction of an X-axis, Vx−, and a wind speed in the forward direction of the X-axis Vx+; and the Y-direction wind speed probe assembly is configured to measure a Y-direction wind speed including a wind speed in reverse direction of an Y-axis, Vy−, and a wind speed in the forward direction of the Y-axis, Vy+.

An overheat detection system for an aircraft, the system comprising a first bleed monitoring computer, BMC1, configured to identify leakages in a pneumatic system, the BMC1 including a first optical controller, a second bleed monitoring computer, BMC2, the BMC2 including a second optical controller, an optical fiber link connecting the first optical controller of the BMC1 and the second optical controller of the BMC2 for communication between the BMC1 and the BCM2 and between the first optical controller and the second optical controller, wherein the first and the second optical controllers are configured to detect overheat of the optical fiber link based on a wavelength shift of a modulated optical signal transmitted through the optical fiber link, and transmit signals to the first BMC1 and the second BMC2 based at least on the detected overheat.

An overheat detection system for an aircraft, the system comprising a first bleed monitoring computer, BMC1, configured to identify leakages in a pneumatic system, the BMC1 including a first optical controller, a second bleed monitoring computer, BMC2, the BMC2 including a second optical controller, an optical fiber link connecting the first optical controller of the BMC1 and the second optical controller of the BMC2 for communication between the BMC1 and the BCM2 and between the first optical controller and the second optical controller, wherein the first and the second optical controllers are configured to detect overheat of the optical fiber link based on a wavelength shift of a modulated optical signal transmitted through the optical fiber link, and transmit signals to the first BMC1 and the second BMC2 based at least on the detected overheat.

An optical fiber mold device has a first portion that includes a base layer having a longitudinal feature configured to receive an optical fiber. At least one second portion is disposed over the base layer. The second portion has a center wall and front and back end walls. The center wall, the front end wall, and the back end wall form a mold cavity. At least one first hole is disposed in the mold cavity and is configured to allow mold material to enter the mold cavity. At least one second hole in the mold cavity is configured to allow air displaced by the mold material to exit the mold cavity.