The shift mechanism of Bragg wavelength with stress variation for a fiber grating is investigated in detail. The influence of strain change on reflection and bandpass is theoretically analyzed. By applying stress, the...The shift mechanism of Bragg wavelength with stress variation for a fiber grating is investigated in detail. The influence of strain change on reflection and bandpass is theoretically analyzed. By applying stress, the dynamic single/dual channel filter with tunable fiber Bragg gratings is achieved.展开更多
Relation of optical properties in a uniform fiber Bragg grating(FBG) with its grating parameters and the laser beam engraving conditions is analyzed. The principle and method for designing the uniform FBG used in dens...Relation of optical properties in a uniform fiber Bragg grating(FBG) with its grating parameters and the laser beam engraving conditions is analyzed. The principle and method for designing the uniform FBG used in dense wavelength division multiplexing(DWDM) system is given. By adopting the double exposure technique, with a uniform phase mask and Gaussian laser beam, the uniform FBG used in DWDM system is designed and engraved, whose bandwidth of the main reflection band is about 0.4 nm and 0.7 nm at -5 dB and -25 dB respectively.展开更多
In recent years, with the rapid development of China's economic construction, the traditional project cost management model has been unable to meet the requirements of current project cost control. The whole proce...In recent years, with the rapid development of China's economic construction, the traditional project cost management model has been unable to meet the requirements of current project cost control. The whole process engineering consultation model is an important means of engineering cost management in the new era. Based on this model, relevant enterprises can embody the cost consultation service in the whole process of engineering construction. More in-depth and comprehensive implementation of project cost management, reasonable control of project cost budget, to assist the construction side in high quality and high efficiency completion while saving project cost.展开更多
文摘The shift mechanism of Bragg wavelength with stress variation for a fiber grating is investigated in detail. The influence of strain change on reflection and bandpass is theoretically analyzed. By applying stress, the dynamic single/dual channel filter with tunable fiber Bragg gratings is achieved.
文摘Relation of optical properties in a uniform fiber Bragg grating(FBG) with its grating parameters and the laser beam engraving conditions is analyzed. The principle and method for designing the uniform FBG used in dense wavelength division multiplexing(DWDM) system is given. By adopting the double exposure technique, with a uniform phase mask and Gaussian laser beam, the uniform FBG used in DWDM system is designed and engraved, whose bandwidth of the main reflection band is about 0.4 nm and 0.7 nm at -5 dB and -25 dB respectively.
文摘In recent years, with the rapid development of China's economic construction, the traditional project cost management model has been unable to meet the requirements of current project cost control. The whole process engineering consultation model is an important means of engineering cost management in the new era. Based on this model, relevant enterprises can embody the cost consultation service in the whole process of engineering construction. More in-depth and comprehensive implementation of project cost management, reasonable control of project cost budget, to assist the construction side in high quality and high efficiency completion while saving project cost.
