Application of Wireless Monitoring System to Structural Health Monitoring of Long-Spanned Cable-Stayed Bridge

The remote monitoring system applied to the construction control and health monitoring of the Nanjing Third Yangtze River Bridge is introduced. The System makes it possible to get the structure capabilities and environmental parameters of the bridge at the predetermined moment. It sends the collected data over a long distance to an assigned position for display and analysis. The related methods and working condition of the wireless monitoring system are discussed. The measured data during 48 h are employed to determine the feasibility for the closure of the bridge.

Development of Welding Multi-Information Remote Wireless Monitoring System Based on STM32

A single sensor is used to obtain welding information in welding monitoring process, but this method has some shortcomings. In order to obtain more comprehensive and reliable welding information, this paper designed and built a welding multi-information wireless monitoring system with STM32-F407ZET6 as the control core and ALK8266 as the wireless transmission module. Real-time acquisition, transmission and display of electric arc signal and welding image information are realized in the monitoring system. This paper mainly introduces the hardware and software core of the monitoring system. At the same time, the signal collected by the monitoring system is compared with the original signal, and the accuracy of the remote monitoring system is tested. The monitoring system is used in welding test. The test results show that the accuracy of the monitoring system meets the requirements, and the on-line monitoring of electric arc signal and welding image can be realized in the welding process.

Wireless remote spatiotemporal monitoring of high-fill foundation deformation

The spatial and temporal deformation patterns and deformation control indicators of highfill foundations directly affect the design,construction and operational safety of high-fill projects.In situ monitoring can comprehensively reflect the deformation of high-fill during and after construction.In this paper,we have first designed and installed an integrated wireless remote monitoring system for high-fill to achieve real-time dynamic monitoring of settlement,pore water pressure and soil pressure of the fill foundation.Based on the monitoring results of nearly one year of the construction period and two years after construction,it was found that the deformation amount and deformation rate of the high-fill foundation showed a non-linear growth relationship with the filling rate and filling height.The settlement deformation of the high-fill foundation during the loading period was mainly dominated by the original foundation soil,accounting for 54.4%of the total settlement on average;the settlement deformation during the post-construction period was mainly dominated by the filling body,accounting for 77.04%of the total settlement on average,and the settlement deformation during the post-construction period mainly occurred in the first year after construction.The analysis of the deformation mechanism suggests that the deformation of the filling body is dominated by exhaust consolidation during the loading period and drainage consolidation during the post-construction period;the deformation of the original foundation soil is dominated by drainage consolidation during the loading period and drainage consolidation develops slowly during the post-construction period.It is recommended that the original foundation should be reinforced before the large area filling construction,and that the filling rate should be strictly controlled during construction.The research results can provide a scientific basis for deformation calculation and stability assessment of high-fill foundations.

A Design of Modern Greenhouse Environmental Monitoring System

Based on the problems in the current greenhouse environmental monitoring system such as difficult connection layout,low flexibility and high costs,this paper builds the greenhouse environmental monitoring system based on wireless sensor network,and designs the sensor nodes and gateway nodes. The sensor nodes of this system are responsible for collecting environmental parameters and sending the data to gateway nodes via wireless sensor network. And the gateway nodes transmit the data to the remote monitoring platform. The microprocessor module of node hardware uses MSP430F149 microprocessor for data processing and control; wireless communication module consists of nRF905 RF chip and peripheral circuit,responsible for transmitting and receiving data; sensor module uses AM2301 sensor for data measurement; the power supply module uses the circuit consisting of LT1129-3. 3,LT1129-5 and Max660 to provide 3. 3 and ± 5V power. The C language development is employed for wireless routing protocol of node and time synchronization algorithm,to achieve node data acquisition and processing,rule forwarding and remote transmission. Remote monitoring software uses NET. ASP,HTML and C# development to provide visual WEB mode remote data management platform for users. The system goes through networking testing in greenhouse in Xining City,and test results show that the system operation is stable and reliable,and the average network packet loss rate is 2. 4%,effectively solving the problems in greenhouse environmental monitoring system and meeting the application requirements of greenhouse cultivation environmental monitoring.

Self-powered wireless environmental monitoring system for in-service bridges by galloping piezoelectric-triboelectric hybridized energy harvester

The energy harvesting technology for the ubiquitous natural wind enables a desirable solution to the issue of distributed sensors in the bridge environmental sensing Internet of Things(Io T)system being restricted to conventional energy supply.In this work,a self-powered system based on a compact galloping piezoelectric-triboelectric energy harvester(GPTEH)is developed to achieve efficient wind energy harvesting.The GPTEH is constructed on the prototype of a cantilever structure with piezoelectric macro-fiber composite(MFC)sheets and a rectangular bluff body with triboelectric nanogenerators(TENGs).Through a special swing-type structural design with iron blocks inside the bluff body,the GPTEH exhibits preferable aerodynamic behavior and excellent energy conversion efficiency,compared to conventional cantilever kind of piezoelectric wind energy harvester(PWEH).The GPTEH also demonstrates the capability of high output power density(PEH of 23.65 W m^(-2)and TENG of 1.59 W m^(-2)),superior response wind speed(about 0.5 m s^(-1)),and excellent long-term stability(over 14000 cyclic tests).Furthermore,a power management system is developed to efficiently utilize the output energy from GPTEH to power the sensors and wirelessly transmit environmental data to the terminals.The proposed GPTEH-powered system exhibits a great potential for the bridge environmental monitoring and Io T technologies.

Adaptive Signal Enhancement Unit for EEG Analysis in Remote Patient Care Monitoring Systems

In this paper we propose an efcient process of physiological artifact elimination methodology from brain waves(BW),which are also commonly known as electroencephalogram(EEG)signal.In a clinical environment during the acquisition of BW several artifacts contaminates the actual BW component.This leads to inaccurate and ambiguous diagnosis.As the statistical nature of the EEG signal is more non-stationery,adaptive ltering is the more promising method for the process of artifact elimination.In clinical conditions,the conventional adaptive techniques require many numbers of computational operations and leads to data samples overlapping and instability of the algorithm used.This causes delay in diagnosis and decision making.To overcome this problem in our work we propose to set a threshold value to diminish the problem of round off error.The resultant adaptive algorithm based on this strategy is Non-linear Least mean square(NL2MS)algorithm.Again,to improve this algorithm in terms of ltering capability we perform data normalization,using this algorithm several hybrid versions are developed to improve ltering and reduce computational operations.Using the method,a new signal enhancement unit(SEU)is realized and performance of various hybrid versions of algorithms examined using real EEG signals recorded from the subject.The ability of the proposed schemes is measured in terms of convergence,enhancement and multiplications required.Among various SEUs,the MCN2L 2MS algorithm achieves 14.6734,12.8732,10.9257,15.7790 dB during the artifact removal of RA,EMG,CSA and EBA components with only two multiplications.Hence,this algorithm seems to be better candidate for artifact elimination.

Method to deploy wireless relays in industrial wireless monitoring

In light of demands for wireless monitoring and the characteristics of wireless channel,a complete deployment method containing channel survey,path loss estimation,and gradient grade of wireless relay nodes is proposed.It can be proved by experiments that under the premise of meeting the requirements of real-time and redundant-topology,the total number of relay nodes could be minimized by using the proposed method.

Stretchable, self‐healable, and breathable biomimetic iontronics with superior humidity‐sensing performance for wireless respiration monitoring

Stretchable,self‐healing,and breathable skin‐biomimetic‐sensing iontronics play an important role in human physiological signal monitoring and human–computer interaction.However,previous studies have focused on the mimicking of skin tactile sensing(pressure,strain,and temperature),and the development of more functionalities is necessary.To this end,a superior humidity‐sensitive ionic skin is developed based on a self‐healing,stretchable,breathable,and biocompatible polyvinyl alcohol–cellulose nanofibers organohydrogel film,showing a pronounced thickness‐dependent humidity‐sensing performance.The as‐prepared 62.47‐μm‐thick organohydrogel film exhibits a high response(25,000%)to 98%RH,excellent repeatability,and long‐term stability(120 days).Moreover,this ionic skin has excellent resistance to large mechanical deformation and damage,and the worn‐out material can still retain its humidity‐sensing capabilities after self‐repair.Humidity‐sensing mechanism studies show that the induced response is mainly related to the increase of proton mobility and interfacial charge transport efficiency after water adsorption.The superior humidity responsiveness is attributed to the reduced thickness and the increased specific surface area of the organohydrogel film,allowing real‐time recording of physiological signals.Notably,by combining with a self‐designed printed circuit board,a continuous and wireless respiration monitoring system is developed,presenting its great potential in wearable and biomedical electronics.

A low-power Bluetooth-based wireless sensor network and its global confliction-solving impact localization method

During the whole service lifetime of aircraft structures with composite materials,impacts are inevitable and can usually cause severe but barely visible damages.Since the occurrences of impact are random and unpredictable,it is a hotspot direction to develop an online impact monitoring system that can meet strict limitations of aerospace applications including small size,light weight,and low power consumption.Piezoelectric(PZT)sensor,being able to generate impact response signals with no external power and cover a large-scale structure with only a small amount of them,is a promising choice.Meanwhile,for real systems,networks with multiple nodes are normally required to monitor large-scale structures in a global way to identify any impact localization confliction,yet the existing studies are mostly evaluated with single nodes instead of networks.Therefore,in this paper,based on a new low-power node designed,a Bluetooth-based digital impact monitoring PZT sensor network is proposed for the first time with its global confliction-solving impact localization method.Evaluations of the system as a network are researched and analyzed on a complex real aircraft wing box for a global confliction-solving impact localization,showing a satisfying high accuracy.

A Real-time Monitoring System Based on ZigBee and 4G Communications for Photovoltaic Generation

A novel real-time monitoring system for photovoltaic(PV)generation is presented in this paper.Internet of Things(IoT)integrated with cloud servers and terminal applications allow the remote monitoring of centralized or distributed pho-tovoltaic systems.The proposed system could realize the net-working communication of multiple nodes based on ZigBee,and upload the operational data to the cloud server via a 4G communications network.Then,the server selects three-phase current as the sample sets from the uploaded data to set up a composite current characteristic combining wavelet packet en-ergy with waveform parameter,and establishes a fault diagnosis model based on the probabilistic neural network to analyze the health status of the PV inverter online.This method requires little sampling frequency without an extra signal and saves the cost of local devices by placing online diagnostics on the server-side.In addition,the user could query and store the running information of the PV systems through the personal computer-side web or mobile phone with remote control.This article presents the hardware design of ZigBee and the 4G module,and composition of the diagnosis model for open circuit failure of the PV inverter through the cloud server,building the user software at the application layer.The final experimental results show that the proposed system has better communication performance and higher diagnostic accuracy in real-time monitoring.

Coil-levitated hybrid generator for mechanical energy harvesting and wireless temperature and vibration monitoring

The development of wireless monitoring is currently restricted by the short lifetime of batteries,requiring frequent replacement.Utilization of abundant mechanical energy from the surrounding environment has attracted increasing attention in real-time monitoring.Herein,a coil-levitated hybrid generator was developed for the efficient harvesting of mechanical energy from mechanical motion.The novel coil-levitated structure adapted to the metal and magnetic environment.The output currents were systematically analyzed at different operation modes based on the unique combination of triboelectrification,electromagnetic induction,and piezoelectric effect.Under the excitation of vibration frequency and amplitude of 8 Hz and 5 mm respectively,the as-constructed triboelectric nanogenerator delivered a peak power density of 11.40 W/m3 at 10 MΩ.Meanwhile,the middle electromagnetic part and bottom piezoelectric generator provided peak power densities of 6.97 and 79.93 W/m2 at 10000Ω,respectively.More importantly,the battery charging experiment was verified,in which a 30 mA h Li-ion battery can be charged from 2.57 to 3.27 V in about 90 min.In sum,a self-powered temperature and vibration monitoring system was successfully developed based on hybrid generator,promising for realizing wireless monitoring of mechanical equipment without any external power supply.

A DATA MINING METHOD BASED ON CONSTRUCTIVE NEURAL NETWORKS

In this letter,Constructive Neural Networks (CNN) is used in large-scale data mining. By introducing the principle and characteristics of CNN and pointing out its deficiencies,fuzzy theory is adopted to improve the covering algorithms. The threshold of covering algorithms is redefined. "Extended area" for test samples is built. The inference of the outlier is eliminated. Furthermore,"Sphere Neighborhood (SN)" are constructed. The membership functions of test samples are given and all of the test samples are determined accordingly. The method is used to mine large wireless monitor data (about 3×107 data points),and knowledge is found effectively.

Pulse Generation and Compression Techniques for Microwave Electronics and Ultrafast Systems

Ultrabroadband systems and ultrafast electronics require the generation,transmission,and processing of high-quality ultrashort pulses rang-ing from nanoseconds(ns)to picoseconds(ps),which include well-established and emerging applications of time-domain reflectometry,arbitrary wave-form generation,sampling oscilloscopes,frequency synthesis,through-wall radar imaging,indoor communication,radar surveillance,and medical radar detection.Impulse radar advancements in industrial,scientific,and medical(ISM)domains are,for example,driven by ns-scale-defined ultrawideband(UWB)technologies.Nevertheless,the generation of ultrashort ps-scale pulses is highly desired to achieve unprecedented performances in all these ap-plications and future systems.However,due to the variety and applicability of different pulse generation and compression techniques,the selection of optimum or appropriate pulse generators and compressors is difficult for practitioners and users.To this end,this article aims to provide a comprehen-sive overview of ultrashort ns and ps pulse generation and compression techniques.The proposed and developed pulse generators available in the litera-ture and on the market,which are characterized by their corresponding pros and cons,are also explored.The theoretical analysis of pulse generation us-ing a nonlinear transmission line(NLTL)presented in the literature is briefly explained as well.Additionally,a holistic overview of these pulse genera-tors from the perspective of applications is given to describe their utilization in practical systems.All of these techniques are well summarized and com-pared in terms of fundamental pulse parameters,and research gaps in specified areas are highlighted.A thorough discussion of previous research work on various topologies and techniques is presented,and potential future directions for technical advancement are examined.

A static-dynamic energy harvester for a self-powered ocean environment monitoring application

Ocean intelligent buoy is important for ocean environment monitoring.With the increase of requisite sensors and transportable data,a long power supply has become a problem to be solved urgently.In this work,a hybrid nanogenerator integrating triboelectric,piezoelectric,electromagnetic,photovoltaic,and thermotropic units is proposed to maximize ocean ambient energy harvesting,which includes static energy(solar and thermal energy)and dynamic energy(wave energy).Compared with a device with a single energy conversion mechanism,this structural design breaks the limit of harvesting time and natural conditions during the energy harvesting process,thereby increasing the harvested energy.Static energy harvesting is realized by the thermoelectric(TG)and photovoltaic(PV)units located inside the device and the PV unit attached to the device surface.Results show that the maximum open-circuit voltage and short-circuit current are 5 V and 41 mA in the external PV and 1.33 V and 49 mA in the internal PV under 30000 Lux illumination,respectively.The open-circuit voltage and short-circuit current of the TG unit are 5 V and 15 m A,respectively.The core component of the dynamic generation unit is the gimbal used to harvest wave energy by the triboelectric nanogenerator(TENG),piezoelectric generator(PENG),and electromagnetic generator.When the frequency is 2.4 Hz,the maximum peak-to-peak power of the TENG,PENG,and EMG are 0.25,1.58,and 13.8 mW,respectively.Finally,an intelligent ocean buoy is fabricated by the integration of an energy harvester,a power management circuit,sensors,a microcontroller,and a wireless communication module.Driven by static and dynamic energy,temperature signal,humidity signal,GPS signal,and sound signal are sent to the receiving terminal wirelessly.The ocean energy harvester proposed in this work is of great significance for ocean energy harvesting and ocean wireless monitoring systems.

A Transactive Energy Model for Smart Metering Systems Using Blockchain

The lowering cost of electricity generation technologies by renewable means has caused the role of end-users to change from being a simple consumer to a producer of their energy.This new role has been called a prosumer and has contributed to modifying electricity markets,by allowing prosumers to merchandize the energy surplus to electricity companies and other prosumers.The fundamental key to any economic transaction is trust between the parties.Recently,new technologies,such as blockchain,are transforming transaction security,and allowing decentralization of the smart power grid.This study presents the development of a transactional model of electrical energy using the infrastructure of smart metering and blockchain systems to allow the commercialization of electrical energy by prosumers.The results show that for the Mexican electricity market,they can he good alternatives hy reducing subsidies and being more profitable than current rates.

A Typical Review on Static Reconfiguration Strategies in Photovoltaic Array Under Non-Uniform Shading Conditions

Maximum power extraction from the photovoltaic(PV) system plays a critical role in increasing efficiency duringpartial shading conditions (PSCs). It directly reduces the outputpower of the PV array. There are different factors, such as bypassdiode configuration, array size, array configuration, shade intensity, environmental conditions etc., affecting the performance ofthe solar photovoltaic panel. Furthermore, series (S), parallel (P),series-parallel (SP), total-cross-tied (TCT), bridge-linked (BL),and honey-comb (HC), etc., are the various configurations to dealwith the mentioned issues. But these PV array configurations alsohave drawbacks, such as low dispersion factor, mismatch losses,and line losses under partial shading conditions. To overcomethese issues, the reconfiguration of the PV array is one of theeffective approaches. A comprehensive study of literature showsthat PV modules are connected under different reconfiguredschemes namely Sudoku, Optimal Sudoku, Magic square, zigzag, Skyscraper, etc. In this paper, a comprehensive review isperformed to highlight the advantages and limitations of eachscheme. This study can be used to address the advancementin this area since some parameter comparisons are made at theend of every technique, which might be a prominent base-rule forpicking the most promising reconfiguration technique for furtherresearch.