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- 实验方案
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Highly Responsive PEG/Gold Nanoparticle Thin Film Humidity Sensor via Inkjet Printing Technology
摘要: In this study, a highly responsive humidity sensor is developed by printing gold nanoparticles (GNP) grafted with a hygroscopic polymer. These GNPs are inkjet printed to form a uniform thin film over an interdigitated electrode with controllable thickness by adjusting the printing parameters. The resistance of the printed GNP thin film decreases significantly upon exposure to water vapor and exhibits a semi-log relationship with relative humidity (RH). The sensor can detect RH variations from 1.8% to 95% with large resistance changes up to 4 order of magnitude with no hysteresis and small temperature dependence. In addition, with a thin thickness, the sensor can reach absorption equilibrium quickly with response and recovery times of ≤1.2 and ≤3 seconds, respectively. The fast response to humidity changes also allows the GNP thin film sensor to distinguish signals from intermittent humidification/dehumidification cycles with a frequency up to 2.5 Hz. The printed sensors on flexible substrates show little sensitivity to bending deformation and can be embedded in a mask for human respiratory detection. In summary, this study demonstrates the feasibility of applying printing technology for the fabrication of thin film humidity sensors, and the developed methodology can be further applied to fabricate many other types of nanoparticle based sensor devices.
关键词: inkjet printing,respiratory monitoring,Humidity sensor,gold nanoparticle,poly(ethylene glycol)
更新于2025-09-23 15:23:52
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Interfacial adhesion between embedded fibre optic sensors and epoxy matrix in composites
摘要: Fibre optic (FO) sensors are becoming increasingly popular for different applications in structural monitoring. Among their excellent properties, a strong interest for this type of sensors are represented by the possibility of embedding FOs inside composite components. In this case, one of the factors that significantly influence the efficiency of the whole Structural Health Monitoring (SHM) system is the interfacial adhesion between FO sensors and the host material. The main objective of this work is to investigate the interfacial adhesion between embedded fibre optic sensors and epoxy matrix to find the best type of optical fibre to be used in epoxy matrices to produce smart composites. Four types of optical fibres with different diameters and coatings (i.e. polyimide, polyacrylate and ormoceramic) were used. Pull-out tests were carried out and different methods were used to obtain the composite/optical fibre interfacial properties. Finally, an optical microscopy and Scanning Electron Microscopy (SEM) analysis were performed to characterize the fibre/matrix interfaces. It was found that the optical fibre that presented the highest energy required for interface rupture and, consequently, less invasiveness to the host material was the ormoceramic fibre with the smallest diameter.
关键词: Structural health monitoring,Pull-out test,interfacial adhesion,fibre optics sensors
更新于2025-09-23 15:23:52
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Characterisation of Timepix3 with 3D sensor
摘要: Tests were performed at the SPS facilities at CERN using a 40 GeV/c pion beam with prototype 3D-Timepix3 detectors (3D detector). A planar-Timepix3 (planar detector) was placed along the beam axis together with the 3D detectors in a telescope arrangement for comparison and reference. We demonstrate that the combination of 3D-geometry silicon sensors and Timepix3 module can reduce the effect of charge sharing and lowers the carrier drift-time, while giving the same spectroscopy performance without sacrificing the timing or any performance advantages of the Timepix3 module.
关键词: Performance of High Energy Physics Detectors,databases),Detector control systems (detector and experiment monitoring and slow-control systems,hardware,algorithms,architecture
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE Global Humanitarian Technology Conference (GHTC) - San Jose, CA, USA (2018.10.18-2018.10.21)] 2018 IEEE Global Humanitarian Technology Conference (GHTC) - Design and Implementation of a Monitoring System for Decision Support in a Micro-Business Based on Solar Energy Microgrid in Rural Colombia
摘要: Rural electri?cation schemes are necessary for social and economic development. In several countries of Africa, Asia and Latin America this issue is fundamental and some governments have adopted new policies to increase service coverage, a case that has been studied with interest is Colombia. In 2014, the Government presented the Law 1715 for Regulating the Integration of Non Conventional Renewable Energies into the National Energy System. This Law aims to increase penetration of renewable energy in the country; and in 2016 the Peace Treaty between the Colombian Government and the Fuerzas Armadas Revolucionarias de Colombia (FARC-EP) was signed. These two events have paved the way towards a new country in which rural development based on technological advances and renewable energy becomes trend. This paper presents a case study that illustrates how technology has transformed the life of one community in the rural area in Colombia by triggering economic development. The technological proposal is the design of a monitoring system for a refrigeration center. The processes of design, implementation and validation with the rural community are presented.
关键词: Monitoring,User Interface,Rural Electri?cation,Capacity building,Educational Technology
更新于2025-09-23 15:23:52
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Subsea Cable Condition Monitoring with Distributed Optical Fibre Vibration Sensor
摘要: A novel subsea cable condition monitoring technique based on embedded optical fibre inside the cable is demonstrated. It is shown that a distributed optical fibre vibration sensor can be used to map dynamic strains all along the cable simultaneously. It is experimentally shown that such system can fully quantify the location and strain level at each point on the cable as a function of time for both abrupt impact and cyclical loading. The sensing system demonstrated a spatial and strain resolution of 1m and 4με, respectively, over a 10km sensing range.
关键词: Offshore wind farm,Cable fault monitoring,Subsea cable monitoring,Distributed Vibration Sensor (DVS),Submarine cable installation,Distributed Acoustic Sensor (DAS)
更新于2025-09-23 15:22:29
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[IEEE 2018 International Conference on Intelligent and Innovative Computing Applications (ICONIC) - Mon Tresor, Plaine Magnien, Mauritius (2018.12.6-2018.12.7)] 2018 International Conference on Intelligent and Innovative Computing Applications (ICONIC) - Development of an IR-based Device for Wireless Communication in Community Health Centres
摘要: With the increase in implementation of advanced communication equipment, especially in the medical sector, finding solutions to anticipated problems has become paramount. Our envisaged problem is the uneasy procedure of taking patients’ variables frequently in community health centers, where there is usually minimal support staff. This paper indicates that human variables such as body temperature and movement at a special ward in a community health care center are transferable from one computer to another. However, our implementation integrated a temperature sensor (LM35), pyroelectric infrared, and infrared to a low-cost Arduino-generic Lilypad microcontroller (as the transmitter). The developed device was able to communicate with the receiver side (comprised of Arduino Mega, infrared receiver, and a computer). We were able to transfer data seamlessly from Mr. C. E. Ngene to a remote computer for analysis. This project will make up for the unavailability of expensive devices and low workforce in the rural community health centers. This designed device can help patients to be attended to quickly as the patients start to have issues.
关键词: sensors,infrared,health,remote monitoring,optical wireless communication
更新于2025-09-23 15:22:29
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Fibre Bragg grating sensor applications for structural health monitoring
摘要: Purpose – Structural health monitoring (SHM) has become an attractive subject in aerospace engineering ?eld considering the opportunity to avoid catastrophic failures by detecting damage in advance and to reduce maintenance costs. Fibre Bragg Grating (FBG) sensors are denoted as one of the most promising sensors for SHM applications as they are lightweight, immune to electromagnetic effects and able to be embedded between the layers of composite structures. The purpose of this paper is to research on and demonstrate the feasibility of FBG sensors for SHM of composite structures. Design/methodology/approach – Applications on thin composite beams intended for SHM studies are presented. The sensor system, which includes FBG sensors and related interrogator system, and manufacturing of the beams with embedded sensors, are detailed. Static tension and torsion tests are conducted to verify the effectiveness of the system. Strain analysis results obtained from the tests are compared with the ones obtained from the ?nite element analyses conducted using ABAQUS? software. In addition, the comparison between the data obtained from the FBG sensors and from the strain gauges is made by also considering the noise content. Finally, fatigue test under torsion load is conducted to observe the durability of FBG sensors. Findings – The results demonstrated that FBG sensors are feasible for SHM of composite structures as the strain data are accurate and less noisy compared to that obtained from the strain gauges. Furthermore, the convenience of obtaining reliable data between the layers of a composite structure using embedded FBG sensors is observed. Practical implications – Observing the advantages of the FBG sensors for strain measurement will promote using FBG sensors for damage detection related to the SHM applications. Originality/value – This paper presents applications of FBG sensors on thin composite beams, which reveal the suitability of FBG sensors for SHM of lightweight composite structures.
关键词: Torsion test,Tension test,Structural health monitoring,Composite beams,Fibre Bragg grating sensors
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Macau, Macao (2018.9.26-2018.9.28)] 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Perfectly Synchronized Streaming from Digitally Modulated Multiple Backscatter Sensor Tags
摘要: This paper proposes a multiple access method, referred to as Multiple Subcarrier Multiple Access (MSMA), for perfectly synchronized concurrent data collection from a group of passive backscatter wireless sensor tags and its experimental evaluation. By achieving less than 128 micro second synchronization error, backscatter communications can be applied to structural health monitoring of artifacts such as civil structures and machineries. In MSMA, each sensor tag uses a dedicated subcarrier frequency to produce a modulated backscatter. The sensor data is superposed onto the subcarrier either with an analog or a digital modulation. The inevitable harmonics among the subcarriers, stemming from the backscatter principle, can be rejected by numerically calculating the harmonic replicas and subtracting them from the observed signal in a software defined receiver. A frame based signal processing in the receiver results in no relative synchronization error among subcarriers even after the interference rejection. Since the interference rejection can be done before the demodulation and decoding, the concurrency can be secured irrespective to the choice of modulation method. We developed a prototype of MSMA using LabVIEW communications Software Defined Radio environment and prototype sensor tags using discrete electrical parts. The performances and limitation of MSMA using digitally modulated subcarriers are evaluated both in wired and wireless environments with up to four backscatter sensors.
关键词: Structural Health Monitoring,Software Defined Radio,Interference Rejection,Passive backscatter
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Macau (2018.9.26-2018.9.28)] 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Secondary Near Field RFID Antennas for Wireless Structural Health Monitoring Systems
摘要: In this paper it is shown that a conductive feed used to excite a standing surface wave on a metallic object can be used to reliably power a passive UHF RFID sensor tag mounted to the same. The read rates of this method and that of free space are compared. Findings show that along the metallic bar structure, and for a greater distance, minimum read rates were at least 9 times greater than in free space. The maximum read rates were found to be around 20 times larger than in free space. It is shown that by utilizing the metallic structure itself, as a secondary nearfield antenna, it is possible to read accelerometer sensor data effectively from a passive UHF sensor tag such as the WISP 5.0. Such a technique may provide a low cost alternative to traditional SHM systems.
关键词: structural health monitoring,acceleration,UHF RFID,metal,sensing,WISP
更新于2025-09-23 15:22:29
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Towards Unsupervised Flood Mapping Generation Using Automatic Thresholding and Classification Aproaches
摘要: This paper presents an unsupervised flood monitoring approach developed by DARES TECHNOLOGY using Synthetic Aperture Radar (SAR) space-borne images in order to improve disaster management and coordinate response activities in front of flood crisis events. The methodology developed combines SAR pre-processing, histogram thresholding in blocks with bi-modal behavior and unsupervised segmentation approaches. The use of interferometric parameters, such as the coherence is also employed to refine results. The challenge of this detection approach is working towards an unsupervised approach, i.e., training data is no required and, therefore, information or ground-truth about the class statistics within the area of interest are not necessary. The methodology proposed will be validated over the floods occurred in Mumbai city on August 29, 2017 produced by heavy rain events. 4 Sentinel-1 SAR images will be employed for this purpose.
关键词: Flood Monitoring,Sentinel-1,SAR
更新于2025-09-23 15:22:29