In a recent study,Prof.Rui Min and collaborators published their paper in the journal of Opto-Electronic Science that is entitled"Smart photonic wristband for pulse wave monitoring".The paper introduces nove...In a recent study,Prof.Rui Min and collaborators published their paper in the journal of Opto-Electronic Science that is entitled"Smart photonic wristband for pulse wave monitoring".The paper introduces novel realization of a sensor that us-es a polymer optical multi-mode fiber to sense pulse wave bio-signal from a wrist by analyzing the specklegram mea-sured at the output of the fiber.Applying machine learning techniques over the pulse wave signal allowed medical diag-nostics and recognizing different gestures with accuracy rate of 95%.展开更多
We proposed a fiber optic high temperature sensor based on the Mach-Zehnder interference(MZI)structure,which is composed of two lengths of multi-mode fibers(MMFs),a length of few-mode fiber(FMF)and two sections of sin...We proposed a fiber optic high temperature sensor based on the Mach-Zehnder interference(MZI)structure,which is composed of two lengths of multi-mode fibers(MMFs),a length of few-mode fiber(FMF)and two sections of single-mode fibers(SMFs).Firstly,the two sections of MMFs were spliced with two sections of SMFs.Then,the MMFs were fused to two ends of FMF to form a symmetrically structured fiber-optic MZI structure.In this structure,the MMF served as the optical mode field coupling element,and the cladding and core of the FMF are the interference arm and the reference arm of the MZI structure,respectively.We investigated the sensor's response characteristics of the temperature and strain.The experimental results indicate that the sensor is sensitive to temperature variation,and the temperature response sensitivity is up to 61.4 pm/℃ in the range of 40-250℃,while the sensor has weak strain sensitivity,its strain sensitivity is only-0.72 pm/μe in the strain range of 0-1400μe.Moreover,the sensor has good stability and repeatability.In brief,the proposed fiber optic high temperature sensor has good properties,such as high sensitivity,compact structure,good stability and repeatability,which can be used for monitoring the temperature of submerged oil electric pump units under oil wells.展开更多
The gestation and occurrence of strong earthquakes are closely related to fault activity, which is not only revealed by abundant experimentation and seismism but also proved by modern seismology. On the Chinese mainla...The gestation and occurrence of strong earthquakes are closely related to fault activity, which is not only revealed by abundant experimentation and seismism but also proved by modern seismology. On the Chinese mainland, the relation between earthquake activity and active faults is one of the bases for partitioning potential seismic sources, analyzing the seismotectoulcs and estimating location of strong earthquakes.Due to the nonuniformity of earth media, instability of observation systems and disturbance of the environment, etc, the variety of observational data is complicated, that is, there is no absolutely ＂normal＂ or ＂abnormal＂, and seismic anomalies can be divided into many mutually exdusive＂ abnormal states＂. In different conditions of combined time-spacestrength, determining seismic anomalies by different monomial forecast methods and its efficiency could be different due to the uncertainty of a precursor itself or complexity of the relationship between a precursor and earthquake gestation. It is very difficult to discover and dispose of this difference in actual application in a ＂two-state＂ model. But in a ＂multi-state＂ model, the difference can be easily reflected and the optimal combination of forecasting parameters for a forecast method can also be determined easily. Based on the ＂multi-state＂ precursory model and the optimization method for parameters of earthquake forecast model under the condition of optimal forecast efficiency, the relationship of the spatial location of earthquake with M ≥ 6.0 and active faults in three seismic belts are analyzed. The results demonstrate that in the Hetao Seismic Belt, seismicity is mostly concentrated in the range of 20 km along the fault, the optimization model can forecast the location of potential earthquakes of M ≥ 6.0 near the faults with a relatively high accuracy and the reliability is 0.5 ; while in the Qilian Mt. Seismic Belt, the reliability only reaches 0.14 when we use the model to estimate earthquakes within 30 km range along the faults. The ＂multi-state＂ precursory model, the efficiency-evaluating model and the parameter selection of individual earthquake forecast model based on optimal efficiency are of certain revelatory and practicable meanings for developing knowledge about precursors, investigating the laws of earthquake preparation and searching for optimal forecasting methods.展开更多
Gyroscopes are crucial components of inertial navigation systems,with ongoing development emphasizing miniaturization and enhanced accuracy.The recent advances in chip-scale optical gyroscopes utilizing integrated opt...Gyroscopes are crucial components of inertial navigation systems,with ongoing development emphasizing miniaturization and enhanced accuracy.The recent advances in chip-scale optical gyroscopes utilizing integrated optics have attracted considerable attention,demonstrating significant advantages in achieving tactical-grade accuracy.In this paper,a new,to our knowledge,integrated optical gyroscope scheme based on the multi-mode co-detection technology is proposed,which takes the high-Q microcavity as its core sensitive element and uses the multi-mode characteristics of the microcavity to achieve the measurement of rotational angular velocity.This detection scheme breaks the tradition of optical gyroscopes based on a single mode within the sensitive ring to detect the angular rotation rate,which not only greatly simplifies the optical and electrical system of the optical gyroscope,but also has a higher detection accuracy.The gyroscope based on this detection scheme has successfully detected the Earth's rotation on a 9.2 mm diameter microcavity with a bias instability as low as 1 deg/h,which is the best performance among the chip-scale integrated optical gyroscopes known to us.展开更多
Spatial photonic Ising machines,as emerging artificial intelligence hardware solutions by leveraging unique physical phenomena,have shown promising results in solving large-scale combinatorial problems.However,spatial...Spatial photonic Ising machines,as emerging artificial intelligence hardware solutions by leveraging unique physical phenomena,have shown promising results in solving large-scale combinatorial problems.However,spatial light modulator enabled Ising machines still remain bulky,are very power demanding,and have poor stability.In this study,we propose an integrated XY Ising sampler based on a highly uniform multimode interferometer and a phase shifter array,enabling the minimization of both discrete and continuous spin Hamiltonians.We elucidate the performance of this computing platform in achieving fully programmable spin couplings and external magnetic fields.Additionally,we successfully demonstrate the weighted full-rank Ising model with a linear dependence of 0.82 and weighted MaxCut problem solving with the proposed sampler.Our results illustrate that the developed structure has significant potential for larger-scale,reduced power consumption and increased operational speed,positioning it as a versatile platform for commercially viable high-performance samplers of combinatorial optimization problems.展开更多
文摘In a recent study,Prof.Rui Min and collaborators published their paper in the journal of Opto-Electronic Science that is entitled"Smart photonic wristband for pulse wave monitoring".The paper introduces novel realization of a sensor that us-es a polymer optical multi-mode fiber to sense pulse wave bio-signal from a wrist by analyzing the specklegram mea-sured at the output of the fiber.Applying machine learning techniques over the pulse wave signal allowed medical diag-nostics and recognizing different gestures with accuracy rate of 95%.
基金supported by the Scientific Research Program Funded by Shaanxi Provincial Education Department (No.15JK1573)the Postgraduate Innovation and Practice Ability Development Fund of Xi’an Shiyou University (No.YCS21211084)。
文摘We proposed a fiber optic high temperature sensor based on the Mach-Zehnder interference(MZI)structure,which is composed of two lengths of multi-mode fibers(MMFs),a length of few-mode fiber(FMF)and two sections of single-mode fibers(SMFs).Firstly,the two sections of MMFs were spliced with two sections of SMFs.Then,the MMFs were fused to two ends of FMF to form a symmetrically structured fiber-optic MZI structure.In this structure,the MMF served as the optical mode field coupling element,and the cladding and core of the FMF are the interference arm and the reference arm of the MZI structure,respectively.We investigated the sensor's response characteristics of the temperature and strain.The experimental results indicate that the sensor is sensitive to temperature variation,and the temperature response sensitivity is up to 61.4 pm/℃ in the range of 40-250℃,while the sensor has weak strain sensitivity,its strain sensitivity is only-0.72 pm/μe in the strain range of 0-1400μe.Moreover,the sensor has good stability and repeatability.In brief,the proposed fiber optic high temperature sensor has good properties,such as high sensitivity,compact structure,good stability and repeatability,which can be used for monitoring the temperature of submerged oil electric pump units under oil wells.
基金This project was sponsored by the Joint Earthquake Science Foundation of CEA(Grant No.103075 and No.104016)
文摘The gestation and occurrence of strong earthquakes are closely related to fault activity, which is not only revealed by abundant experimentation and seismism but also proved by modern seismology. On the Chinese mainland, the relation between earthquake activity and active faults is one of the bases for partitioning potential seismic sources, analyzing the seismotectoulcs and estimating location of strong earthquakes.Due to the nonuniformity of earth media, instability of observation systems and disturbance of the environment, etc, the variety of observational data is complicated, that is, there is no absolutely ＂normal＂ or ＂abnormal＂, and seismic anomalies can be divided into many mutually exdusive＂ abnormal states＂. In different conditions of combined time-spacestrength, determining seismic anomalies by different monomial forecast methods and its efficiency could be different due to the uncertainty of a precursor itself or complexity of the relationship between a precursor and earthquake gestation. It is very difficult to discover and dispose of this difference in actual application in a ＂two-state＂ model. But in a ＂multi-state＂ model, the difference can be easily reflected and the optimal combination of forecasting parameters for a forecast method can also be determined easily. Based on the ＂multi-state＂ precursory model and the optimization method for parameters of earthquake forecast model under the condition of optimal forecast efficiency, the relationship of the spatial location of earthquake with M ≥ 6.0 and active faults in three seismic belts are analyzed. The results demonstrate that in the Hetao Seismic Belt, seismicity is mostly concentrated in the range of 20 km along the fault, the optimization model can forecast the location of potential earthquakes of M ≥ 6.0 near the faults with a relatively high accuracy and the reliability is 0.5 ; while in the Qilian Mt. Seismic Belt, the reliability only reaches 0.14 when we use the model to estimate earthquakes within 30 km range along the faults. The ＂multi-state＂ precursory model, the efficiency-evaluating model and the parameter selection of individual earthquake forecast model based on optimal efficiency are of certain revelatory and practicable meanings for developing knowledge about precursors, investigating the laws of earthquake preparation and searching for optimal forecasting methods.
基金National Key Research and Development Program of China(2023YFB3906402)。
文摘Gyroscopes are crucial components of inertial navigation systems,with ongoing development emphasizing miniaturization and enhanced accuracy.The recent advances in chip-scale optical gyroscopes utilizing integrated optics have attracted considerable attention,demonstrating significant advantages in achieving tactical-grade accuracy.In this paper,a new,to our knowledge,integrated optical gyroscope scheme based on the multi-mode co-detection technology is proposed,which takes the high-Q microcavity as its core sensitive element and uses the multi-mode characteristics of the microcavity to achieve the measurement of rotational angular velocity.This detection scheme breaks the tradition of optical gyroscopes based on a single mode within the sensitive ring to detect the angular rotation rate,which not only greatly simplifies the optical and electrical system of the optical gyroscope,but also has a higher detection accuracy.The gyroscope based on this detection scheme has successfully detected the Earth's rotation on a 9.2 mm diameter microcavity with a bias instability as low as 1 deg/h,which is the best performance among the chip-scale integrated optical gyroscopes known to us.
基金National Natural Science Foundation of China(62175146,62235011)。
文摘Spatial photonic Ising machines,as emerging artificial intelligence hardware solutions by leveraging unique physical phenomena,have shown promising results in solving large-scale combinatorial problems.However,spatial light modulator enabled Ising machines still remain bulky,are very power demanding,and have poor stability.In this study,we propose an integrated XY Ising sampler based on a highly uniform multimode interferometer and a phase shifter array,enabling the minimization of both discrete and continuous spin Hamiltonians.We elucidate the performance of this computing platform in achieving fully programmable spin couplings and external magnetic fields.Additionally,we successfully demonstrate the weighted full-rank Ising model with a linear dependence of 0.82 and weighted MaxCut problem solving with the proposed sampler.Our results illustrate that the developed structure has significant potential for larger-scale,reduced power consumption and increased operational speed,positioning it as a versatile platform for commercially viable high-performance samplers of combinatorial optimization problems.
