A reactor temperature measurement system includes a Fiber Bragg Grating sensor array arranged in a body of the reactor for monitoring temperatures at multiple positions in an axial direction of the body to obtain temperature sensing optical signals; and a fiber grating demodulator, connected to the Fiber Bragg Grating sensor array, and used to demodulate the temperature sensing optical signals. A method for preparing a Fiber Bragg Grating includes preparing a Fiber Bragg Grating by using a single-mode fiber and annealing the Fiber Bragg Grating, which includes heating the Fiber Bragg Grating to a temperature above 400° C. and maintaining for 100 to 200 hours.

A fiber Bragg grating (FBG) security component for single-party and multi-party monitoring is provided. The security component includes an optical fiber having a plurality of Bragg gratings. The Bragg gratings provide a spectral response that is randomized based on the manufacture of the security component. For single-party use, the spectral response provides a reproducible spectral signature when interrogated with an optical signal. For multi-party use, each party applies a known optical interrogation signal to the security component and applies an external stress known only to the respective monitoring party. The resulting shift in the spectral signature is unique to each monitoring party, making it extremely difficult to successfully counterfeit the security component's response for all such parties.

A fiber Bragg grating (FBG) security component for single-party and multi-party monitoring is provided. The security component includes an optical fiber having a plurality of Bragg gratings. The Bragg gratings provide a spectral response that is randomized based on the manufacture of the security component. For single-party use, the spectral response provides a reproducible spectral signature when interrogated with an optical signal. For multi-party use, each party applies a known optical interrogation signal to the security component and applies an external stress known only to the respective monitoring party. The resulting shift in the spectral signature is unique to each monitoring party, making it extremely difficult to successfully counterfeit the security component's response for all such parties.

A medical device that includes a carrier member, one or more operative components disposed in the carrier member, an optical fiber at least partly disposed in the carrier member, and at least one fiber Bragg grating (FBG) sensor array associated with the optical fiber and disposed in the carrier member. The carrier member includes an insertion end and side walls that contact the subject's body during positioning of the carrier member in the subject's body. The at least one FBG sensor array measures contact forces at one or both of the insertion end and along the side walls of the carrier member during positioning of the carrier member in the subject's body. A multi-core optical fiber configured for use in a medical device for positioning in a subject's body is also provided. A system and method for guiding positioning of a medical device in a subject's body is also provided.

A medical device that includes a carrier member, one or more operative components disposed in the carrier member, an optical fiber at least partly disposed in the carrier member, and at least one fiber Bragg grating (FBG) sensor array associated with the optical fiber and disposed in the carrier member. The carrier member includes an insertion end and side walls that contact the subject's body during positioning of the carrier member in the subject's body. The at least one FBG sensor array measures contact forces at one or both of the insertion end and along the side walls of the carrier member during positioning of the carrier member in the subject's body. A multi-core optical fiber configured for use in a medical device for positioning in a subject's body is also provided. A system and method for guiding positioning of a medical device in a subject's body is also provided.

Provided are a monitoring device, a monitoring method, and an optical transmission system which are adapted for an increase in the number of cores of a multi-core optical fiber transmission path and suitable for crosstalk monitoring. The monitoring device monitors a multi-core optical fiber transmission path having a plurality of use cores and at least one or more non-use cores, and comprises: an applying means for applying, at a start point of the multi-core optical fiber transmission path, dithering to signal light propagating in the use cores; a monitoring means for monitoring the power of the non-use cores at an input side of a relay in the multi-core optical fiber transmission path; and a separating means for separating a monitoring result from the monitoring means into power components from the plurality of use cores.

Provided are a monitoring device, a monitoring method, and an optical transmission system which are adapted for an increase in the number of cores of a multi-core optical fiber transmission path and suitable for crosstalk monitoring. The monitoring device monitors a multi-core optical fiber transmission path having a plurality of use cores and at least one or more non-use cores, and comprises: an applying means for applying, at a start point of the multi-core optical fiber transmission path, dithering to signal light propagating in the use cores; a monitoring means for monitoring the power of the non-use cores at an input side of a relay in the multi-core optical fiber transmission path; and a separating means for separating a monitoring result from the monitoring means into power components from the plurality of use cores.

An integrated anchoring structure of basalt fiber reinforced plastic (BFRP) bars for a reservoir bank slope includes: a plurality of BFRP anchoring bars, where each of the BFRP anchoring bars includes a plurality of BFRP bars bonded to one another, a lower steel casing pipe, an upper steel casing pipe and a steel strand bonded to an upper portion of the upper steel casing pipe and aligned with the BFRP bars, and a grating array temperature sensing optical cable, a grating array stress sensing optical cable and a grating array vibration sensing optical cable are bonded in each of the BFRP bars; a plurality of shear-resistant bricks distributed on structural planes; a pouring base arranged at a bottom of the anchoring borehole; and an anchoring section arranged at an upper portion of the pouring base.

An integrated anchoring structure of basalt fiber reinforced plastic (BFRP) bars for a reservoir bank slope includes: a plurality of BFRP anchoring bars, where each of the BFRP anchoring bars includes a plurality of BFRP bars bonded to one another, a lower steel casing pipe, an upper steel casing pipe and a steel strand bonded to an upper portion of the upper steel casing pipe and aligned with the BFRP bars, and a grating array temperature sensing optical cable, a grating array stress sensing optical cable and a grating array vibration sensing optical cable are bonded in each of the BFRP bars; a plurality of shear-resistant bricks distributed on structural planes; a pouring base arranged at a bottom of the anchoring borehole; and an anchoring section arranged at an upper portion of the pouring base.

Provided is an apparatus for determining the temperature of at least one fluid. The apparatus includes an optical fiber. A first end of the optical fiber is connected to at least one fiber tip, and a first additional reflector is introduced into the at least one fiber tip at a first predetermined distance from an outer end of the at least one fiber tip. A second end of the optical fiber is connected to a processing apparatus. The processing apparatus includes an optical source. The optical source is configured to launch an optical signal into the optical fiber, and a coherent detector. The coherent detector is configured to determine the temperature of at least one fluid by receiving a first light signal that corresponds to parts of the optical signal that are reflected at the outer end of the at least one fiber tip when the at least one fiber tip is inserted into the at least one fluid and a second light signal that corresponds to parts of the optical signal that are reflected at the first additional reflector when the at least one fiber tip is inserted into the at least one fluid, determining a difference of the optical phases of the first light signal and the second light signal, and determining the temperature of the at least one fluid based on the difference of the optical phases of the first light signal and the second light signal.