To discuss the relative slipping at the interface between a flexibly embedded fiber Bragg grating sensor and a substrate,the strain transfer was derived for an ideal case between the materials of an embedded fiber sen...To discuss the relative slipping at the interface between a flexibly embedded fiber Bragg grating sensor and a substrate,the strain transfer was derived for an ideal case between the materials of an embedded fiber sensor.ANSYS software was used to establish a simulation model and to analyze the effects of the axial tensile force and the semi-embedded length and encapsulation substrate for the axial strain relative errors with and without relative slipping.The results of the numerical simulations show that the relative strain errors are smaller at the ends of the fibers and larger in the middle for the same tensile force,indicating that the strain transfer effect is location dependent and that the choice of a semi-embedded length of the fibers greater than 40 mm helps to reduce the relative errors.Meanwhile,five flexible sensors with different half-embedding lengths were experimentally encapsulated and subjected to axial tension-strain experiments,which showed the best strain transfer at a half-embedding length of 60 mm,and the experimental results were consistent with the numerical simulation results.The experimental results provide some theoretical and experimental basis for parameter optimization of flexible fiber grating sensors.展开更多
Green finance is an important driving force for practicing the idea of green development and realizing sustainable development. As one of the five green finance reform and innovation demonstration district in China, t...Green finance is an important driving force for practicing the idea of green development and realizing sustainable development. As one of the five green finance reform and innovation demonstration district in China, the Guian New District between Guiyang and Anshun has played a key leading role in the development of green finance in southwest China. Since 2017, the green financial market in Guizhou province has achieved a leap-forward high-speed development. Based on this, this paper takes the idea of green development as the starting point, through in-depth analysis of the development status of green finance in Guizhou province under the policy control and guidance of the national and local governments,in order to find the limitations and obstacles in the development of green finance in Guian New District.In addition, at the end of this article, the author will further discuss the mechanism and path of green financial reform and innovation in Guizhou province from the aspects of perfecting policy guidance, optimizing organizational system, innovating products and services, etc. for effectively promoting the pace of green development in Guizhou province.展开更多
To obtain the influence rules of the coating parameters of a long-period fiber grating(LPFG)with respect to temperature,strain and refractive index sensing properties,based on the mode coupling theory,a strict four-la...To obtain the influence rules of the coating parameters of a long-period fiber grating(LPFG)with respect to temperature,strain and refractive index sensing properties,based on the mode coupling theory,a strict four-layer theorietical model of a metal film coated LPFG is established,and these parameters that affect the spectral characteristics of the metal film coated LPFG are studied.The simulation results show that there is an optimal metal film thickness on the surface of the LPFG that will induce the surface-plasmon resonance(SP R)effect,which results in higher sensitivity to the environmental temperature and refractive index but has little influence on the strain There is theoretical evidence that when the silver thickness is between0.8and1.2nm,the refractive index sensitivity will reach the peak point of42.4026,at which the refractive index sensor sensitivity is increased by4.S%.The theoretical results of coating a long-period fiber grating provide a good theoretical basis and guidance for LPFG design and parameters optimization展开更多
基金supported by the Subproject of National Key Research and Development Program of China(No.2017 YFC0805103)。
文摘To discuss the relative slipping at the interface between a flexibly embedded fiber Bragg grating sensor and a substrate,the strain transfer was derived for an ideal case between the materials of an embedded fiber sensor.ANSYS software was used to establish a simulation model and to analyze the effects of the axial tensile force and the semi-embedded length and encapsulation substrate for the axial strain relative errors with and without relative slipping.The results of the numerical simulations show that the relative strain errors are smaller at the ends of the fibers and larger in the middle for the same tensile force,indicating that the strain transfer effect is location dependent and that the choice of a semi-embedded length of the fibers greater than 40 mm helps to reduce the relative errors.Meanwhile,five flexible sensors with different half-embedding lengths were experimentally encapsulated and subjected to axial tension-strain experiments,which showed the best strain transfer at a half-embedding length of 60 mm,and the experimental results were consistent with the numerical simulation results.The experimental results provide some theoretical and experimental basis for parameter optimization of flexible fiber grating sensors.
文摘Green finance is an important driving force for practicing the idea of green development and realizing sustainable development. As one of the five green finance reform and innovation demonstration district in China, the Guian New District between Guiyang and Anshun has played a key leading role in the development of green finance in southwest China. Since 2017, the green financial market in Guizhou province has achieved a leap-forward high-speed development. Based on this, this paper takes the idea of green development as the starting point, through in-depth analysis of the development status of green finance in Guizhou province under the policy control and guidance of the national and local governments,in order to find the limitations and obstacles in the development of green finance in Guian New District.In addition, at the end of this article, the author will further discuss the mechanism and path of green financial reform and innovation in Guizhou province from the aspects of perfecting policy guidance, optimizing organizational system, innovating products and services, etc. for effectively promoting the pace of green development in Guizhou province.
基金National Natural Science Foundation of China(No.51309001)Scientific Research Key Project of Anhui Province(No.KJ2017A041)
文摘To obtain the influence rules of the coating parameters of a long-period fiber grating(LPFG)with respect to temperature,strain and refractive index sensing properties,based on the mode coupling theory,a strict four-layer theorietical model of a metal film coated LPFG is established,and these parameters that affect the spectral characteristics of the metal film coated LPFG are studied.The simulation results show that there is an optimal metal film thickness on the surface of the LPFG that will induce the surface-plasmon resonance(SP R)effect,which results in higher sensitivity to the environmental temperature and refractive index but has little influence on the strain There is theoretical evidence that when the silver thickness is between0.8and1.2nm,the refractive index sensitivity will reach the peak point of42.4026,at which the refractive index sensor sensitivity is increased by4.S%.The theoretical results of coating a long-period fiber grating provide a good theoretical basis and guidance for LPFG design and parameters optimization
