A distributed optical-fiber acoustic sensor is an acoustic sensor that uses the optical fiber itself as a photosensitive medium,and is based on Rayleigh backscattering in an optical fiber.The sensor is widely used in ...A distributed optical-fiber acoustic sensor is an acoustic sensor that uses the optical fiber itself as a photosensitive medium,and is based on Rayleigh backscattering in an optical fiber.The sensor is widely used in the safety monitoring of oil and gas pipelines,the classification of weak acoustic signals,defense,seismic prospecting,and other fields.In the field of seismic prospecting,distributed optical-fiber acoustic sensing(DAS)will gradually replace the use of the traditional geophone.The present paper mainly expounds the recent application of DAS,and summarizes recent research achievements of DAS in resource exploration,intrusion monitoring,pattern recognition,and other fields and various DAS system structures.It is found that the high-sensitivity and long-distance sensing capabilities of DAS play a role in the extensive monitoring applications of DAS in engineering.The future application and development of DAS technology are examined,with the hope of promoting the wider application of the DAS technology,which benefits engineering and society.展开更多
Wireless transmission method in wireless sensor networks has put forward higher requirements for private protection technology. According to the packet loss problem of private protection algorithm based on slice techn...Wireless transmission method in wireless sensor networks has put forward higher requirements for private protection technology. According to the packet loss problem of private protection algorithm based on slice technology, this paper proposes the data private protection algorithm with redundancy mechanism, which ensures privacy by privacy homomorphism mechanism and guarantees redundancy by carrying hidden data. Moreover,it selects the routing tree generated by CTP(Collection Tree Protocol) as routing path for data transmission. By dividing at the source node, it adds the hidden information and also the privacy homomorphism. At the same time,the information feedback tree is established between the destination node and the source node. In addition, the destination node immediately sends the packet loss information and the encryption key via the information feedback tree to the source node. As a result,it improves the reliability and privacy of data transmission and ensures the data redundancy.展开更多
Wireless Sensor Network (WSN) which is composed of lots of self-organizational intelligence nodes has become new technology of information acquisition and processing. Location technology is one of the key technologies...Wireless Sensor Network (WSN) which is composed of lots of self-organizational intelligence nodes has become new technology of information acquisition and processing. Location technology is one of the key technologies in WSN. There are many kinds of location algorithms currently and the research to performance evaluation and applicability analysis of algorithms has fundamental significance. For this reason, the paper firstly elaborated the performance evaluation indexes of location algorithms, and analyzed the location prin-ciples, characteristics and current fundamental problems to typical and some new location algorithms, and then analyzed and compared some typical location algorithms according to the location accuracy, node den-sity and hardware requirement, obtaining the sphere of application of these algorithms and pointing out the problems which need to be solved in WSN currently.展开更多
This paper focuses on techniques in utilizing remote sensor technology for precision crop production by farmers as climate change adaptation strategy in Nigeria. Descriptive survey research design was adopted for the ...This paper focuses on techniques in utilizing remote sensor technology for precision crop production by farmers as climate change adaptation strategy in Nigeria. Descriptive survey research design was adopted for the study and was carried out between August 2013 and May 2014. The findings of the study revealed that 32 items were needed by farmers in utilizing sensory technology for precision crop production. The study recommended that the 32 items identified by the study should be utilized by extension agent in teaching the farmers the use of sensor technology for precision crop production while the farmers should make themselves available for the training.展开更多
The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryo...The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryogenic field and magnetic field. The response to a temperature and strain change of coated-soft polymeric FBGs is tested by comparing with those of coated-metal FBGs. The results indicate that the coated-soft polymeric FBGs can freely detect temperature and thermal strain, their At variable magnetic field, the tested results indicate accuracy and repeatability are also discussed in detail. that the cross-coupling effects of FBGs with different matrixes are not negligible to measure electromagnetic strain during fast excitation. The present results are expected to be able to provide basis measurements on the strain of pulsed superconducting magnet/cable （cable- around-conduit conductors, cable-in-conduit conductors）, independently or utilized together with other strain measurement methods.展开更多
To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-typ...To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-type structure and microsphere structure is proposed in this paper. The fiber sidepolishing technique converts the coaxial dual-waveguide fiber into a D-type one, and the evanescent wave in the ring core leaks, generating a D-type sensing region;the fiber optic fused ball push technology converts the coaxial dual waveguides into microspheres, and the stimulated cladding mode evanescent wave leaks, producing the microsphere sensing region. By injecting light into the coaxial dual-waveguide middle core alone, the sensor can realize single-stage sensing in the microsphere sensing area;it can also realize dual-channel sensing in the D-type sensing area and microsphere sensing area by injecting light into the ring core. The refractive index measurement ranges for the two channels are 1.333–1.365 and 1.375–1.405, respectively, with detection sensitivities of 981.56 nm/RIU and 4138 nm/RIU. The sensor combines wavelength division multiplexing and space division multiplexing technologies, presenting a novel research concept for multi-channel fiber SPR sensors.展开更多
Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face chal...Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face challenges,including complex fabrication processes and limited response times.Here,we propose a fiber-optic H_(2) sensing tip based on Tamm plasmon polariton(TPP)resonance,consisting of a multilayer metal/dielectric Bragg reflector deposited directly on the fiber end facet,simplifying the fabrication process.The fiber-optic TPP(FOTPP)tip exhibits both TPP and multiple Fabry-Perot(FP)resonances simultaneously,with the TPP employed for highly sensitive H_(2) detection.Compared to FP resonance,TPP exhibits more than twice the sensitivity under the same structural dimension without cavity geometry deformation.The excellent performance is attributed to alterations in phase-matching conditions,driven by changes in penetration depth of TPP.Furthermore,the FP mode is utilized to achieve an efficient photothermal effect to catalyze the reaction between H_(2) and the FOTPP structure.Consequently,the response and recovery speeds of the FOTPP tip under resonance-enhanced photothermal assistance are improved by 6.5 and 2.1 times,respectively.Our work offers a novel strategy for developing TPP-integrated fiber-optic tips,refines the theoretical framework of photothermal-assisted detection systems,and provides clear experimental evidence.展开更多
Marine environmental monitoring and data platform technology plays a pivotal role in advancing marine scientific research,sustainable resource development,ecological conservation,and the effective utilization of ocean...Marine environmental monitoring and data platform technology plays a pivotal role in advancing marine scientific research,sustainable resource development,ecological conservation,and the effective utilization of ocean resources.Despite its growing importance in addressing global environmental and economic challenges,a comprehensive and systematic review of recent advancements in this field remains lacking.To address this gap,this paper synthesizes and analyzes academic literature published between 2021 and 2025,sourced from reputable databases including Scopus and Web of Science,while adhering to the PRISMA systematic review standards.It delineates core technologies employed in marine environmental monitoring,such as advanced sensor systems,robust data acquisition and transmission methods,and innovative data processing and analysis techniques.Furthermore,the study examines the architectural functionalities,data sharing mechanisms,and interoperability standards that underpin modern marine data platforms.The paper also addresses critical technical challenges encountered in deep-water monitoring operations,including equipment durability under extreme conditions,significant economic constraints,data management complexities,and emerging privacy and security concerns.Finally,future development trajectories are outlined,emphasizing the transformative potential of novel materials and artificial intelligence(AI)in enhancing deep-water monitoring capabilities,alongside the urgent need for strengthened global collaboration to improve data sharing protocols and management frameworks.Collectively,the continuous evolution of marine monitoring technologies promises to provide increasingly intelligent,integrated,and systematic support for global marine protection efforts and sustainable resource stewardship.展开更多
BACKGROUND Diagnostic errors in critical care settings are a significant challenge,often leading to adverse patient outcomes and increased healthcare costs.Millimeter-wave(mmWave)technology,with its ability to provide...BACKGROUND Diagnostic errors in critical care settings are a significant challenge,often leading to adverse patient outcomes and increased healthcare costs.Millimeter-wave(mmWave)technology,with its ability to provide high-resolution,real-time data,offers a transformative solution to enhance diagnostic accuracy and patient safety.This paper explores the integration of mmWave technology in intensive care units(ICUs)to enable non-invasive monitoring,minimize diagnostic errors,and improve clinical decision-making.By addressing key challenges,including data latency,signal interference,and implementation feasibility,this approach has the potential to revolutionize patient monitoring systems and set a new standard for critical care delivery.The paper discusses the high prevalence of diagnostic errors in medical care,particularly in primary care and ICUs,and emphasizes the need for improvement in diagnostic accuracy.Diagnostic errors are responsible for a significant number of deaths,disabilities,prolonged hospitalizations and delays in diagnosis worldwide.AIM To address this issue,the paper proposes the use of ultrafast wireless medical big data transmission in primary care,specifically in remote smart sensors monitoring devices.It suggests that wireless transmission with a speed up to 100 Gb/s(12.5 Gbytes/s)within a short distance(1-10 meters)is necessary to reduce diagnostic errors.METHODS The method used in the study,includes system design and testing a channel sounder operating at 63.4-64.4 GHz frequency range.The system demonstrated dynamic range of 70 dB,noise level of-110 dBm,and a time resolution of 1 ns.The experiment measured the impulse response of the channel in 36 locations within the primary care/ICU scenario.RESULTS The system was tested in a simulated ICU environment to evaluate the Latency:Assessing the time delay in data transmission and processing.The results of the study showed that the system met the requirements of ICUs,providing excellent latency values.The delay spread and excess delay values were within acceptable limits,indicating successful resolution of ICU requirements.The paper suggests timely deployment of such a system.Impact on data transmission:A 100 MB magnetic resonance imaging scan can be transmitted in approximately 0.008 seconds;A 1 GB scan would take approximately 0.08 seconds;This capability could revolutionize healthcare,enabling real-time remote diagnostics and comparisons with artificial Intelligence models,even in large-scale systems.CONCLUSION The experiment demonstrated the feasibility of using high-speed wireless transmission for improved diagnostics in ICUs,offering potential benefits in terms of reduced errors and improved patient outcomes.The findings are deemed valuable to the medical community and public healthcare systems,and it is suggested further research in this area.展开更多
Complex surface shape measurement has been a focus topic in the CAD/CAM field. A popular method for measuring dimensional information is using a 3D coordinate measuring machine (CMM)with a touch trigger probe. The mea...Complex surface shape measurement has been a focus topic in the CAD/CAM field. A popular method for measuring dimensional information is using a 3D coordinate measuring machine (CMM)with a touch trigger probe. The measurement set up with CMM, however, is a time consuming task and the accuracy of the measurement deteriorates as the speed of measurement increase. Non-contact measurement is favored since high speed measurement can be achieved and problems with vibration and friction can be eliminated. Although much research has been conducted in non-contact measurement using image capturing and processing schemes, accuracy is poor and measurement is limited. Some optical technologies developed provide a good accuracy but the dynamic range and versatility is very limited. A novel fiber-optic sensor used for the inspection of complex internal contours is presented in this paper, which is able to measure a surface shape in a non-contact manner with high accuracy and high speed, and is compact and flexible to be incorporated into a CMM. Modulation functions for tilted surface shape measurement, based on the Gaussian distribution of the emitting beam from single-mode fiber (SMF), were derived for specular reflection. The feasibility of the proposed measurement principle was verified by simulations.展开更多
The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual applicatio...The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual application of AHFO technology to the water content measurement of in situ soil.However,all existing in situ applications of AHFO technology fail to consider the effect of soilesensor contact quality on water content measurements,limiting potential for the wider application of AHFO technology.To address this issue,the authors propose a method for determining the soilesensor thermal contact resistance based on the principle of an infinite cylindrical heat source.This is then used to establish an AHFO water content measurement technology that considers the thermal contact resistance.The reliability and validity of the new measurement technology are explored through a laboratory test and a field case study,and the spatial-temporal evolution of the soil water content in the case is revealed.The results demonstrate that method for determining the soilesensor thermal contact resistance is highly effective and applicable to all types of soils.This method requires only the moisture content,dry density,and thermal response of the in situ soil to be obtained.In the field case,the measurement error of soil water content between the AHFO method,which takes into account the thermal contact resistance,and the neutron scattering method is only 0.011.The water content of in situ soil exhibits a seasonal variation,with an increase in spring and autumn and a decrease in summer and winter.Furthermore,the response of shallow soils to precipitation and evaporation is significant.These findings contribute to the enhancement of the accuracy of the AHFO technology in the measurement of the water content of in situ soils,thereby facilitating the dissemination and utilization of this technology.展开更多
An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the ca...An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range.展开更多
The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber link...The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber links the sensor head to the source and detection system, in which the technique of phase shift cancellation is used to cancel the phase shift that accumulatein the optical fiber. Flux concentrators were exploited to enhance the YIG crystal magneto-optic sensitivity .The sensor system exhibited a noise-equivalent field of 8 pT/√Hz and a 3 dB bandwidth of ～10 MHz.展开更多
Multiplexing technologies based on superconducting quantum interference devices(SQUIDs) are crucial to cryogenic readout of superconducting transition-edge sensor(TES) arrays. Demands for large-scale TES arrays promot...Multiplexing technologies based on superconducting quantum interference devices(SQUIDs) are crucial to cryogenic readout of superconducting transition-edge sensor(TES) arrays. Demands for large-scale TES arrays promote the development of multiplexing technologies towards large multiplexing factors and low readout noise. The development of multiplexing technologies also facilitates new applications of TES arrays in a wide range of frequencies. Here we summarize different types of SQUID-based multiplexing technologies including time-division multiplexing, code-division multiplexing, frequency-division multiplexing and microwave SQUID multiplexing. The advances and parameter constraints of each multiplexing technology are also discussed.展开更多
The increasing availability of ubiquitous sensor data on the built environment holds great potential for a new generation of travel and mobility research.Bluetooth technology,for example,is already vastly used in vehi...The increasing availability of ubiquitous sensor data on the built environment holds great potential for a new generation of travel and mobility research.Bluetooth technology,for example,is already vastly used in vehicular transportation management solutions and services.Current studies discuss the potential of this emerging technology for pedestrian mobility research,but it has yet to be examined in a large urban setting.One of the main problems is detecting pedestrians from Bluetooth records since their behavior and movement patterns share similarities with other urban transportation modes.This study aims to accurately detect pedestrians using a network of 65 Bluetooth detectors located in Tel-Aviv,Israel,which record on average over 60,000 unique daily Bluetooth Media-Access-Control addresses.We propose a detection methodology that includes system calibration,effective travel time calculation,and classification by velocity that takes into consideration the probability of vehicular traffic jams.An evaluation of the proposed methodology presents a promising pedestrian detection accuracy rate of 89%.We showcase the results of pedestrian traffic analysis,together with a discussion on the data analysis challenges and limitations.To the best of our knowledge,this work is the first to analyze pedestrian records detection from a Bluetooth network employed in a dynamic urban environment setting.展开更多
In this study, we fabricated a sapphire based fiber-optic radiation sensor. To evaluate the fiber- optic radiation sensor, we measured the spectrum and intensity of the luminescence generated from the fiber-optic radi...In this study, we fabricated a sapphire based fiber-optic radiation sensor. To evaluate the fiber- optic radiation sensor, we measured the spectrum and intensity of the luminescence generated from the fiber-optic radiation sensor according to the thickness of the PMMA block by irradiation of gamma rays emitted from a Co-60 source. And the result was compared with the value calculated from the formula of Lambert-Beer.展开更多
A compact and high-resolution fiber-optic refractive index(RI)sensor based on a microwave photonic filter(MPF)is proposed and experimentally validated.The sensing head utilizes a cascaded in-line interferometer fabric...A compact and high-resolution fiber-optic refractive index(RI)sensor based on a microwave photonic filter(MPF)is proposed and experimentally validated.The sensing head utilizes a cascaded in-line interferometer fabricated by an input single-mode fiber(SMF)tapered fusion with no-core fiber-thin-core fiber(TCF)-SMF.The surrounding RI(SRI)can be demodulated by tracing the passband’s central frequency of the MPF,which is constructed by the cascaded in-line interferometer,electro-optic modulator,and a section of dispersion compensation fiber.The sensitivity of the sensor is tailorable through the use of different lengths of TCF.Experimental results reveal that with a 30 mm length of TCF,the sensor achieves a maximum theoretical sensitivity and resolution of-1.403 GHz∕refractive index unit eRIUT and 1.425×10^(-7) RIU,respectively,which is at least 6.3 times higher than what has been reported previously.Furthermore,the sensor exhibits temperature-insensitive characteristics within the range of 25℃-75℃,with a temperatureinduced frequency change of only±1.5 MHz.This value is significantly lower than the frequency change induced by changes in the SRI.The proposed MPF-based cascaded in-line interferometer RI sensor possesses benefits such as easy manufacture,low cost,high resolution,and temperature insensitivity.展开更多
With the rapid development of the Internet of Things(IoT)technology,fiber-optic sensors,as a kind of high-precision and high-sensitivity measurement tool,are increasingly widely used in the field of IoT.This paper out...With the rapid development of the Internet of Things(IoT)technology,fiber-optic sensors,as a kind of high-precision and high-sensitivity measurement tool,are increasingly widely used in the field of IoT.This paper outlines the advantages of fiber-optic sensors over traditional sensors,such as high precision,strong resistance to electromagnetic interference,and long transmission distance.On this basis,the paper discusses the application scenarios of fiber-optic sensors in the Internet of Things,including environmental monitoring,intelligent industry,medical and health care,intelligent transportation,and other fields.It is hoped that this study can provide theoretical support and practical guidance for the further development of fiber-optic sensors in the field of the Internet of Things,as well as promote the innovation and application of IoT.展开更多
With the integration of modern technology, sensor technology is used to improve the background system. Since sensors primarily use computers to protect data, they are a technology that transforms valuable data into ne...With the integration of modern technology, sensor technology is used to improve the background system. Since sensors primarily use computers to protect data, they are a technology that transforms valuable data into new and improved forms. Based on sensors, they can quickly input information into various fields. So as to give full play to its core advantages, realize functional application, and continuously expand the sensor technology to occupy an effective position. In automatic electromechanical control, the normal work of sensors has a significant impact on the system automation control. Give full play to the key role of sensor technology and automatic control of mechanical operation.展开更多
A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs ...A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs dynamic mon- itoring on the environmental data of temperature, humidity, illumination, soil tempera- ture and humidity of the greenhouse, and it reduces the energy consumption by us- ing solar energy and lithium battery as the power supply mode and dynamic power management algorithm combined with improved routing protocol. Stable and reliable, the system could effectively monitor the key environmental factors in the green- house, making it of certain promotion value.展开更多
基金supported by the Science and Technology Development Plan of Jilin Province(No.20180201036GX)
文摘A distributed optical-fiber acoustic sensor is an acoustic sensor that uses the optical fiber itself as a photosensitive medium,and is based on Rayleigh backscattering in an optical fiber.The sensor is widely used in the safety monitoring of oil and gas pipelines,the classification of weak acoustic signals,defense,seismic prospecting,and other fields.In the field of seismic prospecting,distributed optical-fiber acoustic sensing(DAS)will gradually replace the use of the traditional geophone.The present paper mainly expounds the recent application of DAS,and summarizes recent research achievements of DAS in resource exploration,intrusion monitoring,pattern recognition,and other fields and various DAS system structures.It is found that the high-sensitivity and long-distance sensing capabilities of DAS play a role in the extensive monitoring applications of DAS in engineering.The future application and development of DAS technology are examined,with the hope of promoting the wider application of the DAS technology,which benefits engineering and society.
基金sponsored by the National Key R&D Program of China(No.2018YFB1003201)the National Natural Science Foundation of China(No.61672296,No.61602261)Major Natural Science Research Projects in Colleges and Universities of Jiangsu Province(No.18KJA520008)
文摘Wireless transmission method in wireless sensor networks has put forward higher requirements for private protection technology. According to the packet loss problem of private protection algorithm based on slice technology, this paper proposes the data private protection algorithm with redundancy mechanism, which ensures privacy by privacy homomorphism mechanism and guarantees redundancy by carrying hidden data. Moreover,it selects the routing tree generated by CTP(Collection Tree Protocol) as routing path for data transmission. By dividing at the source node, it adds the hidden information and also the privacy homomorphism. At the same time,the information feedback tree is established between the destination node and the source node. In addition, the destination node immediately sends the packet loss information and the encryption key via the information feedback tree to the source node. As a result,it improves the reliability and privacy of data transmission and ensures the data redundancy.
文摘Wireless Sensor Network (WSN) which is composed of lots of self-organizational intelligence nodes has become new technology of information acquisition and processing. Location technology is one of the key technologies in WSN. There are many kinds of location algorithms currently and the research to performance evaluation and applicability analysis of algorithms has fundamental significance. For this reason, the paper firstly elaborated the performance evaluation indexes of location algorithms, and analyzed the location prin-ciples, characteristics and current fundamental problems to typical and some new location algorithms, and then analyzed and compared some typical location algorithms according to the location accuracy, node den-sity and hardware requirement, obtaining the sphere of application of these algorithms and pointing out the problems which need to be solved in WSN currently.
文摘This paper focuses on techniques in utilizing remote sensor technology for precision crop production by farmers as climate change adaptation strategy in Nigeria. Descriptive survey research design was adopted for the study and was carried out between August 2013 and May 2014. The findings of the study revealed that 32 items were needed by farmers in utilizing sensory technology for precision crop production. The study recommended that the 32 items identified by the study should be utilized by extension agent in teaching the farmers the use of sensor technology for precision crop production while the farmers should make themselves available for the training.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11302225,11121202 and 11327802the National Key Project of Magneto-Constrained Fusion Energy Development Program under Grant No 2013GB110002the Postdoctoral Science Foundation of China under Grant No 2014M560820
文摘The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryogenic field and magnetic field. The response to a temperature and strain change of coated-soft polymeric FBGs is tested by comparing with those of coated-metal FBGs. The results indicate that the coated-soft polymeric FBGs can freely detect temperature and thermal strain, their At variable magnetic field, the tested results indicate accuracy and repeatability are also discussed in detail. that the cross-coupling effects of FBGs with different matrixes are not negligible to measure electromagnetic strain during fast excitation. The present results are expected to be able to provide basis measurements on the strain of pulsed superconducting magnet/cable （cable- around-conduit conductors, cable-in-conduit conductors）, independently or utilized together with other strain measurement methods.
基金supported by the National Natural Science Foundation of China (Grant No. 61705025)the Natural Science Foundation of Chongqing (Grant Nos. cstc2019jcyjmsxm X043 and cstc2018jcyj AX0817)+2 种基金the Fund from the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality (Grant Nos. KJQN201801217, KJQN202001214, KJQN201901226, and KJ1710247)the Fund from Chongqing Key Laboratory of Geological Environment Monitoring and Disaster Early-Warning in Three Gorges Reservoir Area (Grant Nos. ZD2020A0103 and ZD2020A0102)the Fundamental Research Funds for Chongqing Three Gorges University of China (Grant No. 19ZDPY08)。
文摘To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-type structure and microsphere structure is proposed in this paper. The fiber sidepolishing technique converts the coaxial dual-waveguide fiber into a D-type one, and the evanescent wave in the ring core leaks, generating a D-type sensing region;the fiber optic fused ball push technology converts the coaxial dual waveguides into microspheres, and the stimulated cladding mode evanescent wave leaks, producing the microsphere sensing region. By injecting light into the coaxial dual-waveguide middle core alone, the sensor can realize single-stage sensing in the microsphere sensing area;it can also realize dual-channel sensing in the D-type sensing area and microsphere sensing area by injecting light into the ring core. The refractive index measurement ranges for the two channels are 1.333–1.365 and 1.375–1.405, respectively, with detection sensitivities of 981.56 nm/RIU and 4138 nm/RIU. The sensor combines wavelength division multiplexing and space division multiplexing technologies, presenting a novel research concept for multi-channel fiber SPR sensors.
基金financial supports from National Key Research and Development Program of China(2023YFB3209500)National Natural Science Foundation of China(NSFC)(12274052 and 62171076)+1 种基金Fundamental Research Funds for the Central Universities(DUT24ZD203)Bolian Research Funds of Dalian Maritime University and Fundamental Research Funds for the Central Universities(3132024605).
文摘Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face challenges,including complex fabrication processes and limited response times.Here,we propose a fiber-optic H_(2) sensing tip based on Tamm plasmon polariton(TPP)resonance,consisting of a multilayer metal/dielectric Bragg reflector deposited directly on the fiber end facet,simplifying the fabrication process.The fiber-optic TPP(FOTPP)tip exhibits both TPP and multiple Fabry-Perot(FP)resonances simultaneously,with the TPP employed for highly sensitive H_(2) detection.Compared to FP resonance,TPP exhibits more than twice the sensitivity under the same structural dimension without cavity geometry deformation.The excellent performance is attributed to alterations in phase-matching conditions,driven by changes in penetration depth of TPP.Furthermore,the FP mode is utilized to achieve an efficient photothermal effect to catalyze the reaction between H_(2) and the FOTPP structure.Consequently,the response and recovery speeds of the FOTPP tip under resonance-enhanced photothermal assistance are improved by 6.5 and 2.1 times,respectively.Our work offers a novel strategy for developing TPP-integrated fiber-optic tips,refines the theoretical framework of photothermal-assisted detection systems,and provides clear experimental evidence.
文摘Marine environmental monitoring and data platform technology plays a pivotal role in advancing marine scientific research,sustainable resource development,ecological conservation,and the effective utilization of ocean resources.Despite its growing importance in addressing global environmental and economic challenges,a comprehensive and systematic review of recent advancements in this field remains lacking.To address this gap,this paper synthesizes and analyzes academic literature published between 2021 and 2025,sourced from reputable databases including Scopus and Web of Science,while adhering to the PRISMA systematic review standards.It delineates core technologies employed in marine environmental monitoring,such as advanced sensor systems,robust data acquisition and transmission methods,and innovative data processing and analysis techniques.Furthermore,the study examines the architectural functionalities,data sharing mechanisms,and interoperability standards that underpin modern marine data platforms.The paper also addresses critical technical challenges encountered in deep-water monitoring operations,including equipment durability under extreme conditions,significant economic constraints,data management complexities,and emerging privacy and security concerns.Finally,future development trajectories are outlined,emphasizing the transformative potential of novel materials and artificial intelligence(AI)in enhancing deep-water monitoring capabilities,alongside the urgent need for strengthened global collaboration to improve data sharing protocols and management frameworks.Collectively,the continuous evolution of marine monitoring technologies promises to provide increasingly intelligent,integrated,and systematic support for global marine protection efforts and sustainable resource stewardship.
文摘BACKGROUND Diagnostic errors in critical care settings are a significant challenge,often leading to adverse patient outcomes and increased healthcare costs.Millimeter-wave(mmWave)technology,with its ability to provide high-resolution,real-time data,offers a transformative solution to enhance diagnostic accuracy and patient safety.This paper explores the integration of mmWave technology in intensive care units(ICUs)to enable non-invasive monitoring,minimize diagnostic errors,and improve clinical decision-making.By addressing key challenges,including data latency,signal interference,and implementation feasibility,this approach has the potential to revolutionize patient monitoring systems and set a new standard for critical care delivery.The paper discusses the high prevalence of diagnostic errors in medical care,particularly in primary care and ICUs,and emphasizes the need for improvement in diagnostic accuracy.Diagnostic errors are responsible for a significant number of deaths,disabilities,prolonged hospitalizations and delays in diagnosis worldwide.AIM To address this issue,the paper proposes the use of ultrafast wireless medical big data transmission in primary care,specifically in remote smart sensors monitoring devices.It suggests that wireless transmission with a speed up to 100 Gb/s(12.5 Gbytes/s)within a short distance(1-10 meters)is necessary to reduce diagnostic errors.METHODS The method used in the study,includes system design and testing a channel sounder operating at 63.4-64.4 GHz frequency range.The system demonstrated dynamic range of 70 dB,noise level of-110 dBm,and a time resolution of 1 ns.The experiment measured the impulse response of the channel in 36 locations within the primary care/ICU scenario.RESULTS The system was tested in a simulated ICU environment to evaluate the Latency:Assessing the time delay in data transmission and processing.The results of the study showed that the system met the requirements of ICUs,providing excellent latency values.The delay spread and excess delay values were within acceptable limits,indicating successful resolution of ICU requirements.The paper suggests timely deployment of such a system.Impact on data transmission:A 100 MB magnetic resonance imaging scan can be transmitted in approximately 0.008 seconds;A 1 GB scan would take approximately 0.08 seconds;This capability could revolutionize healthcare,enabling real-time remote diagnostics and comparisons with artificial Intelligence models,even in large-scale systems.CONCLUSION The experiment demonstrated the feasibility of using high-speed wireless transmission for improved diagnostics in ICUs,offering potential benefits in terms of reduced errors and improved patient outcomes.The findings are deemed valuable to the medical community and public healthcare systems,and it is suggested further research in this area.
文摘Complex surface shape measurement has been a focus topic in the CAD/CAM field. A popular method for measuring dimensional information is using a 3D coordinate measuring machine (CMM)with a touch trigger probe. The measurement set up with CMM, however, is a time consuming task and the accuracy of the measurement deteriorates as the speed of measurement increase. Non-contact measurement is favored since high speed measurement can be achieved and problems with vibration and friction can be eliminated. Although much research has been conducted in non-contact measurement using image capturing and processing schemes, accuracy is poor and measurement is limited. Some optical technologies developed provide a good accuracy but the dynamic range and versatility is very limited. A novel fiber-optic sensor used for the inspection of complex internal contours is presented in this paper, which is able to measure a surface shape in a non-contact manner with high accuracy and high speed, and is compact and flexible to be incorporated into a CMM. Modulation functions for tilted surface shape measurement, based on the Gaussian distribution of the emitting beam from single-mode fiber (SMF), were derived for specular reflection. The feasibility of the proposed measurement principle was verified by simulations.
基金supported by the National Natural Science Foundation of China(Grant Nos.42307189 and 42030701)the China Postdoctoral Science Foundation(Grant No.2023M740974).
文摘The actively heated fiber-optic(AHFO)technology has become emerged as a research focus due to its advantages of distributed,real-time measurement and good durability.These attributes have led to the gradual application of AHFO technology to the water content measurement of in situ soil.However,all existing in situ applications of AHFO technology fail to consider the effect of soilesensor contact quality on water content measurements,limiting potential for the wider application of AHFO technology.To address this issue,the authors propose a method for determining the soilesensor thermal contact resistance based on the principle of an infinite cylindrical heat source.This is then used to establish an AHFO water content measurement technology that considers the thermal contact resistance.The reliability and validity of the new measurement technology are explored through a laboratory test and a field case study,and the spatial-temporal evolution of the soil water content in the case is revealed.The results demonstrate that method for determining the soilesensor thermal contact resistance is highly effective and applicable to all types of soils.This method requires only the moisture content,dry density,and thermal response of the in situ soil to be obtained.In the field case,the measurement error of soil water content between the AHFO method,which takes into account the thermal contact resistance,and the neutron scattering method is only 0.011.The water content of in situ soil exhibits a seasonal variation,with an increase in spring and autumn and a decrease in summer and winter.Furthermore,the response of shallow soils to precipitation and evaporation is significant.These findings contribute to the enhancement of the accuracy of the AHFO technology in the measurement of the water content of in situ soils,thereby facilitating the dissemination and utilization of this technology.
文摘An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range.
文摘The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber links the sensor head to the source and detection system, in which the technique of phase shift cancellation is used to cancel the phase shift that accumulatein the optical fiber. Flux concentrators were exploited to enhance the YIG crystal magneto-optic sensitivity .The sensor system exhibited a noise-equivalent field of 8 pT/√Hz and a 3 dB bandwidth of ～10 MHz.
基金Project supported by the National Science Foundation of China (Grant Nos. 11653001 and 11653004)。
文摘Multiplexing technologies based on superconducting quantum interference devices(SQUIDs) are crucial to cryogenic readout of superconducting transition-edge sensor(TES) arrays. Demands for large-scale TES arrays promote the development of multiplexing technologies towards large multiplexing factors and low readout noise. The development of multiplexing technologies also facilitates new applications of TES arrays in a wide range of frequencies. Here we summarize different types of SQUID-based multiplexing technologies including time-division multiplexing, code-division multiplexing, frequency-division multiplexing and microwave SQUID multiplexing. The advances and parameter constraints of each multiplexing technology are also discussed.
文摘The increasing availability of ubiquitous sensor data on the built environment holds great potential for a new generation of travel and mobility research.Bluetooth technology,for example,is already vastly used in vehicular transportation management solutions and services.Current studies discuss the potential of this emerging technology for pedestrian mobility research,but it has yet to be examined in a large urban setting.One of the main problems is detecting pedestrians from Bluetooth records since their behavior and movement patterns share similarities with other urban transportation modes.This study aims to accurately detect pedestrians using a network of 65 Bluetooth detectors located in Tel-Aviv,Israel,which record on average over 60,000 unique daily Bluetooth Media-Access-Control addresses.We propose a detection methodology that includes system calibration,effective travel time calculation,and classification by velocity that takes into consideration the probability of vehicular traffic jams.An evaluation of the proposed methodology presents a promising pedestrian detection accuracy rate of 89%.We showcase the results of pedestrian traffic analysis,together with a discussion on the data analysis challenges and limitations.To the best of our knowledge,this work is the first to analyze pedestrian records detection from a Bluetooth network employed in a dynamic urban environment setting.
文摘In this study, we fabricated a sapphire based fiber-optic radiation sensor. To evaluate the fiber- optic radiation sensor, we measured the spectrum and intensity of the luminescence generated from the fiber-optic radiation sensor according to the thickness of the PMMA block by irradiation of gamma rays emitted from a Co-60 source. And the result was compared with the value calculated from the formula of Lambert-Beer.
基金supported by the National Natural Science Foundation of China(Grant No.61975167).
文摘A compact and high-resolution fiber-optic refractive index(RI)sensor based on a microwave photonic filter(MPF)is proposed and experimentally validated.The sensing head utilizes a cascaded in-line interferometer fabricated by an input single-mode fiber(SMF)tapered fusion with no-core fiber-thin-core fiber(TCF)-SMF.The surrounding RI(SRI)can be demodulated by tracing the passband’s central frequency of the MPF,which is constructed by the cascaded in-line interferometer,electro-optic modulator,and a section of dispersion compensation fiber.The sensitivity of the sensor is tailorable through the use of different lengths of TCF.Experimental results reveal that with a 30 mm length of TCF,the sensor achieves a maximum theoretical sensitivity and resolution of-1.403 GHz∕refractive index unit eRIUT and 1.425×10^(-7) RIU,respectively,which is at least 6.3 times higher than what has been reported previously.Furthermore,the sensor exhibits temperature-insensitive characteristics within the range of 25℃-75℃,with a temperatureinduced frequency change of only±1.5 MHz.This value is significantly lower than the frequency change induced by changes in the SRI.The proposed MPF-based cascaded in-line interferometer RI sensor possesses benefits such as easy manufacture,low cost,high resolution,and temperature insensitivity.
文摘With the rapid development of the Internet of Things(IoT)technology,fiber-optic sensors,as a kind of high-precision and high-sensitivity measurement tool,are increasingly widely used in the field of IoT.This paper outlines the advantages of fiber-optic sensors over traditional sensors,such as high precision,strong resistance to electromagnetic interference,and long transmission distance.On this basis,the paper discusses the application scenarios of fiber-optic sensors in the Internet of Things,including environmental monitoring,intelligent industry,medical and health care,intelligent transportation,and other fields.It is hoped that this study can provide theoretical support and practical guidance for the further development of fiber-optic sensors in the field of the Internet of Things,as well as promote the innovation and application of IoT.
文摘With the integration of modern technology, sensor technology is used to improve the background system. Since sensors primarily use computers to protect data, they are a technology that transforms valuable data into new and improved forms. Based on sensors, they can quickly input information into various fields. So as to give full play to its core advantages, realize functional application, and continuously expand the sensor technology to occupy an effective position. In automatic electromechanical control, the normal work of sensors has a significant impact on the system automation control. Give full play to the key role of sensor technology and automatic control of mechanical operation.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(14)2108&CX(13)5066)~~
文摘A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs dynamic mon- itoring on the environmental data of temperature, humidity, illumination, soil tempera- ture and humidity of the greenhouse, and it reduces the energy consumption by us- ing solar energy and lithium battery as the power supply mode and dynamic power management algorithm combined with improved routing protocol. Stable and reliable, the system could effectively monitor the key environmental factors in the green- house, making it of certain promotion value.
