WorldWideScience

Sample records for vibration-based structural health

  1. Vibration-based structural health monitoring of harbor caisson structure

    Science.gov (United States)

    Lee, So-Young; Lee, So-Ra; Kim, Jeong-Tae

    2011-04-01

    This study presents vibration-based structural health monitoring method in foundation-structure interface of harbor caisson structure. In order to achieve the objective, the following approaches are implemented. Firstly, vibration-based response analysis method is selected and structural health monitoring (SHM) technique is designed for harbor caisson structure. Secondly, the performance of designed SHM technique for harbor structure is examined by FE analysis. Finally, the applicability of designed SHM technique for harbor structure is evaluated by dynamic tests on a lab-scaled caisson structure.

  2. Vibration based structural health monitoring in fibre reinforced composites employing the modal strain energy method

    NARCIS (Netherlands)

    Loendersloot, Richard; Ooijevaar, T.H.; Warnet, Laurent; Akkerman, Remko; de Boer, Andries; Meguid, S.A.; Gomes, J.F.S.

    2009-01-01

    The feasibility of a vibration based damage identification method is investigated. The Modal Strain Energy method is applied to a T–beam structure. The dynamic response of an intact structure and a damaged, delaminated structure is analysed employing a commercially available Finite Element package.

  3. A Method for Vibration-Based Structural Interrogation and Health Monitoring Based on Signal Cross-Correlation

    International Nuclear Information System (INIS)

    Trendafilova, I

    2011-01-01

    Vibration-based structural interrogation and health monitoring is a field which is concerned with the estimation of the current state of a structure or a component from its vibration response with regards to its ability to perform its intended function appropriately. One way to approach this problem is through damage features extracted from the measured structural vibration response. This paper suggests to use a new concept for the purposes of vibration-based health monitoring. The correlation between two signals, an input and an output, measured on the structure is used to develop a damage indicator. The paper investigates the applicability of the signal cross-correlation and a nonlinear alternative, the average mutual information between the two signals, for the purposes of structural health monitoring and damage assessment. The suggested methodology is applied and demonstrated for delamination detection in a composite beam.

  4. Vibration-based health monitoring and model refinement of civil engineering structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, C.R.; Doebling, S.W.

    1997-10-01

    Damage or fault detection, as determined by changes in the dynamic properties of structures, is a subject that has received considerable attention in the technical literature beginning approximately 30 years ago. The basic idea is that changes in the structure`s properties, primarily stiffness, will alter the dynamic properties of the structure such as resonant frequencies and mode shapes, and properties derived from these quantities such as modal-based flexibility. Recently, this technology has been investigated for applications to health monitoring of large civil engineering structures. This presentation will discuss such a study undertaken by engineers from New Mexico Sate University, Sandia National Laboratory and Los Alamos National Laboratory. Experimental modal analyses were performed in an undamaged interstate highway bridge and immediately after four successively more severe damage cases were inflicted in the main girder of the structure. Results of these tests provide insight into the abilities of modal-based damage ID methods to identify damage and the current limitations of this technology. Closely related topics that will be discussed are the use of modal properties to validate computer models of the structure, the use of these computer models in the damage detection process, and the general lack of experimental investigation of large civil engineering structures.

  5. Structural health monitoring of a railway truss bridge using vibration-based and ultrasonic methods

    Science.gov (United States)

    Kołakowski, Przemysław; Szelążek, Jacek; Sekuła, Krzysztof; Świercz, Andrzej; Mizerski, Krzysztof; Gutkiewicz, Piotr

    2011-03-01

    This paper presents results of in situ investigation of a railway truss bridge in the context of structural health monitoring (SHM). Three experimental methods are examined. Dynamic responses of the bridge recorded by strain gauges are confronted with alternative ways of acquisition using piezoelectric patch sensors and ultrasonic probeheads. All types of sensors produce similar output. Also the corresponding responses of the numerical model of the bridge match experimental data.

  6. Structural health monitoring of a railway truss bridge using vibration-based and ultrasonic methods

    International Nuclear Information System (INIS)

    Kołakowski, Przemysław; Sekuła, Krzysztof; Szelążek, Jacek; Świercz, Andrzej; Mizerski, Krzysztof; Gutkiewicz, Piotr

    2011-01-01

    This paper presents results of in situ investigation of a railway truss bridge in the context of structural health monitoring (SHM). Three experimental methods are examined. Dynamic responses of the bridge recorded by strain gauges are confronted with alternative ways of acquisition using piezoelectric patch sensors and ultrasonic probeheads. All types of sensors produce similar output. Also the corresponding responses of the numerical model of the bridge match experimental data

  7. Strain sensors optimal placement for vibration-based structural health monitoring. The effect of damage on the initially optimal configuration

    Science.gov (United States)

    Loutas, T. H.; Bourikas, A.

    2017-12-01

    We revisit the optimal sensor placement of engineering structures problem with an emphasis on in-plane dynamic strain measurements and to the direction of modal identification as well as vibration-based damage detection for structural health monitoring purposes. The approach utilized is based on the maximization of a norm of the Fisher Information Matrix built with numerically obtained mode shapes of the structure and at the same time prohibit the sensorization of neighbor degrees of freedom as well as those carrying similar information, in order to obtain a satisfactory coverage. A new convergence criterion of the Fisher Information Matrix (FIM) norm is proposed in order to deal with the issue of choosing an appropriate sensor redundancy threshold, a concept recently introduced but not further investigated concerning its choice. The sensor configurations obtained via a forward sequential placement algorithm are sub-optimal in terms of FIM norm values but the selected sensors are not allowed to be placed in neighbor degrees of freedom providing thus a better coverage of the structure and a subsequent better identification of the experimental mode shapes. The issue of how service induced damage affects the initially nominated as optimal sensor configuration is also investigated and reported. The numerical model of a composite sandwich panel serves as a representative aerospace structure upon which our investigations are based.

  8. Vibration based structural health monitoring of an arch bridge: From automated OMA to damage detection

    Science.gov (United States)

    Magalhães, F.; Cunha, A.; Caetano, E.

    2012-04-01

    In order to evaluate the usefulness of approaches based on modal parameters tracking for structural health monitoring of bridges, in September of 2007, a dynamic monitoring system was installed in a concrete arch bridge at the city of Porto, in Portugal. The implementation of algorithms to perform the continuous on-line identification of modal parameters based on structural responses to ambient excitation (automated Operational Modal Analysis) has permitted to create a very complete database with the time evolution of the bridge modal characteristics during more than 2 years. This paper describes the strategy that was followed to minimize the effects of environmental and operational factors on the bridge natural frequencies, enabling, in a subsequent stage, the identification of structural anomalies. Alternative static and dynamic regression models are tested and complemented by a Principal Components Analysis. Afterwards, the identification of damages is tried with control charts. At the end, it is demonstrated that the adopted processing methodology permits the detection of realistic damage scenarios, associated with frequency shifts around 0.2%, which were simulated with a numerical model.

  9. Vibrational Based Inspection of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Rytter, Anders

    at the University of Aalborg from 1988 to 1991. Secondly, a research project, In-Field Vibration Based Inspection of Civil Engineering Structures, which has been performed as a pilot project by the Consulting Engineers Rambøll, Hannemann and Højlund in cooperation with the department of Building Technology......The thesis has been written in relation to two different research projects. Firstly, an offshore test programme, Integrated Experimental/Numerical Analysis of the Dynamic behavior of offshore structures, which was performed at the department of Building Technology and Structural Engineering...... and Structural Engineering at the University of Aalborg since the beginning of 1992. Both projects have been supported by the Danish Technical Research Council. Further, the first mentioned project was supported by the Danish Energy Agency. Their financial support is gratefully acknowledged....

  10. A vibration-based health monitoring program for a large and seismically vulnerable masonry dome

    Science.gov (United States)

    Pecorelli, M. L.; Ceravolo, R.; De Lucia, G.; Epicoco, R.

    2017-05-01

    Vibration-based health monitoring of monumental structures must rely on efficient and, as far as possible, automatic modal analysis procedures. Relatively low excitation energy provided by traffic, wind and other sources is usually sufficient to detect structural changes, as those produced by earthquakes and extreme events. Above all, in-operation modal analysis is a non-invasive diagnostic technique that can support optimal strategies for the preservation of architectural heritage, especially if complemented by model-driven procedures. In this paper, the preliminary steps towards a fully automated vibration-based monitoring of the world’s largest masonry oval dome (internal axes of 37.23 by 24.89 m) are presented. More specifically, the paper reports on signal treatment operations conducted to set up the permanent dynamic monitoring system of the dome and to realise a robust automatic identification procedure. Preliminary considerations on the effects of temperature on dynamic parameters are finally reported.

  11. Real-time vibration-based structural damage detection using one-dimensional convolutional neural networks

    Science.gov (United States)

    Abdeljaber, Osama; Avci, Onur; Kiranyaz, Serkan; Gabbouj, Moncef; Inman, Daniel J.

    2017-02-01

    Structural health monitoring (SHM) and vibration-based structural damage detection have been a continuous interest for civil, mechanical and aerospace engineers over the decades. Early and meticulous damage detection has always been one of the principal objectives of SHM applications. The performance of a classical damage detection system predominantly depends on the choice of the features and the classifier. While the fixed and hand-crafted features may either be a sub-optimal choice for a particular structure or fail to achieve the same level of performance on another structure, they usually require a large computation power which may hinder their usage for real-time structural damage detection. This paper presents a novel, fast and accurate structural damage detection system using 1D Convolutional Neural Networks (CNNs) that has an inherent adaptive design to fuse both feature extraction and classification blocks into a single and compact learning body. The proposed method performs vibration-based damage detection and localization of the damage in real-time. The advantage of this approach is its ability to extract optimal damage-sensitive features automatically from the raw acceleration signals. Large-scale experiments conducted on a grandstand simulator revealed an outstanding performance and verified the computational efficiency of the proposed real-time damage detection method.

  12. Active vibration-based structural health monitoring system for wind turbine blade: Demonstration on an operating Vestas V27 wind turbine

    DEFF Research Database (Denmark)

    Tcherniak, Dmitri; Mølgaard, Lasse Lohilahti

    2017-01-01

    enough to be able to propagate the entire blade length. This article demonstrates the system on a Vestas V27 wind turbine. One blade of the wind turbine was equipped with the system, and a 3.5-month monitoring campaign was conducted while the turbine was operating normally. During the campaign, a defect......—a trailing-edge opening—was artificially introduced into the blade and its size was gradually increased from the original 15 to 45 cm. Using a semi-supervised learning algorithm, the system was able to detect even the smallest amount of damage while the wind turbine was operating under different weather......This study presents a structural health monitoring system that is able to detect structural defects of wind turbine blade such as cracks, leading/trailing-edge opening, or delamination. It is shown that even small defects of at least 15 cm size can be detected remotely without stopping the wind...

  13. Vibration-based monitoring for performance evaluation of flexible civil structures in Japan

    Science.gov (United States)

    FUJINO, Yozo

    2018-01-01

    The vibration-based monitoring of flexible civil structures and performance evaluation from this monitoring are reviewed, with an emphasis on research and practice in Japan and the author’s experiences. Some new findings and unexpected vibrations from the monitoring of real bridges and buildings are reported to emphasize the importance of monitoring. Future developments and applications of vibration-based monitoring to civil infrastructure management are also described. Many examples are taken from the author’s past 30 years’ experience of research on bridge dynamics. PMID:29434082

  14. Parametric and Non-Parametric Vibration-Based Structural Identification Under Earthquake Excitation

    Science.gov (United States)

    Pentaris, Fragkiskos P.; Fouskitakis, George N.

    2014-05-01

    ]. Preliminary results indicate that parametric methods are capable of sufficiently providing the structural/modal characteristics such as natural frequencies and damping ratios. The study also aims - at a further level of investigation - to provide a reliable statistically-based methodology for structural health monitoring after major seismic events which potentially cause harming consequences in structures. Acknowledgments This work was supported by the State Scholarships Foundation of Hellas. References [1] J. S. Sakellariou and S. D. Fassois, "Stochastic output error vibration-based damage detection and assessment in structures under earthquake excitation," Journal of Sound and Vibration, vol. 297, pp. 1048-1067, 2006. [2] G. Hloupis, I. Papadopoulos, J. P. Makris, and F. Vallianatos, "The South Aegean seismological network - HSNC," Adv. Geosci., vol. 34, pp. 15-21, 2013. [3] F. P. Pentaris, J. Stonham, and J. P. Makris, "A review of the state-of-the-art of wireless SHM systems and an experimental set-up towards an improved design," presented at the EUROCON, 2013 IEEE, Zagreb, 2013. [4] S. D. Fassois, "Parametric Identification of Vibrating Structures," in Encyclopedia of Vibration, S. G. Braun, D. J. Ewins, and S. S. Rao, Eds., ed London: Academic Press, London, 2001. [5] S. D. Fassois and J. S. Sakellariou, "Time-series methods for fault detection and identification in vibrating structures," Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol. 365, pp. 411-448, February 15 2007.

  15. Vibration based structural assessment of the rehabilitation intervention in r.c. segmental bridge

    OpenAIRE

    Franchetti Paolo; Frizzarin Michele; Leonardi Andrea; Zeni Fabio

    2015-01-01

    A vibration based structural assessment campaign was carried out on a r.c. segmental bridge in North East Italy. The bridge has a cantilever static scheme, fixed at the top of the piers and with a hinge at the centre of the span. The particular configuration of the hinge consists in a couple of steel elements, each one composed by a tongue and groove joint. Since the year 1960, the hinge was subjected to consumption and degradation, that caused a malfunctioning of the device. An intervention ...

  16. Vibration-based damage detection of structural joints in presence of uncertainty

    Directory of Open Access Journals (Sweden)

    Al-Bugharbee Hussein

    2018-01-01

    Full Text Available Early damage detection of structure’s joints is essential in order to ensure the integrity of structures. Vibration-based methods are the most popular way of diagnosing damage in machinery joints. Any technique that is used for such a purpose requires dealing with the variability inherent to the system due to manufacturing tolerances, environmental conditions or aging. The level of variability in vibrational response can be very high for mass-produced complex structures that possess a large number of components. In this study, a simple and efficient time frequency method is proposed for detection of damage in connecting joints. The method suggests using singular spectrum analysis for building a reference space from the signals measured on a healthy structure and then compares all other signals to that reference space in order to detect the presence of faults. A model of two plates connected by a series of mounts is used to examine the effectiveness of the method where the uncertainty in the mount properties is taken into account to model the variability in the built-up structure. The motivation behind the simplified model is to identify the faulty mounts in trim-structure joints of an automotive vehicle where a large number of simple plastic clips are used to connect the trims to the vehicle structure.

  17. Stochastic output error vibration-based damage detection and assessment in structures under earthquake excitation

    Science.gov (United States)

    Sakellariou, J. S.; Fassois, S. D.

    2006-11-01

    A stochastic output error (OE) vibration-based methodology for damage detection and assessment (localization and quantification) in structures under earthquake excitation is introduced. The methodology is intended for assessing the state of a structure following potential damage occurrence by exploiting vibration signal measurements produced by low-level earthquake excitations. It is based upon (a) stochastic OE model identification, (b) statistical hypothesis testing procedures for damage detection, and (c) a geometric method (GM) for damage assessment. The methodology's advantages include the effective use of the non-stationary and limited duration earthquake excitation, the handling of stochastic uncertainties, the tackling of the damage localization and quantification subproblems, the use of "small" size, simple and partial (in both the spatial and frequency bandwidth senses) identified OE-type models, and the use of a minimal number of measured vibration signals. Its feasibility and effectiveness are assessed via Monte Carlo experiments employing a simple simulation model of a 6 storey building. It is demonstrated that damage levels of 5% and 20% reduction in a storey's stiffness characteristics may be properly detected and assessed using noise-corrupted vibration signals.

  18. Vibration based structural assessment of the rehabilitation intervention in r.c. segmental bridge

    Directory of Open Access Journals (Sweden)

    Franchetti Paolo

    2015-01-01

    Full Text Available A vibration based structural assessment campaign was carried out on a r.c. segmental bridge in North East Italy. The bridge has a cantilever static scheme, fixed at the top of the piers and with a hinge at the centre of the span. The particular configuration of the hinge consists in a couple of steel elements, each one composed by a tongue and groove joint. Since the year 1960, the hinge was subjected to consumption and degradation, that caused a malfunctioning of the device. An intervention of rehabilitation of the bridge led to a reinforcement of the existing hinges with the coupling of new metallic devices: new tongue and groove hinges were applied, that by one side allow the horizontal displacements and rotation, by the other side strongly reduce the relative vertical displacements of the two parts of the bridge. A dynamic test campaign was set up in order to assess the effectiveness of the intervention. The principal dynamic parameters were calculated and analysed with respect to the intervention that was realized. The tests clearly showed the effectiveness of the intervention, and helped the designer to have a better understanding of the structural behaviour of the bridge.

  19. Modal analysis of a concrete highway bridge : Structural calculations and vibration-based results

    NARCIS (Netherlands)

    Miao, S.; Veerman, R.P.; Koenders, E.A.B.; Knobbe, A.

    2013-01-01

    In the field of civil infrastructure, Structural Health Monitoring systems are implemented more and more frequently with the aim to safeguard the safety and service-life of structures such as bridges and tunnels. Changes in the integrity of the material and/or structural properties of this class of

  20. Vibration-based localisation of structural deterioration in frame-like civil engineering structures

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Damkilde, Lars

    2016-01-01

    With the existing trend of minimising material use in typical frame-like civil engineering structures, such as buildings, bridges, and offshore platforms, these structures will typically be subjected to substantial wind induced vibrations. Besides being a source of disturbance for the occupants...

  1. Application of a robust vibration-based non-destructive method for detection of fatigue cracks in structures

    International Nuclear Information System (INIS)

    Razi, Pejman; Esmaeel, Ramadan A; Taheri, Farid

    2011-01-01

    This paper presents the application of a novel vibration-based technique for detecting fatigue cracks in structures. The method utilizes the empirical mode decomposition method (EMD) to establish an effective energy-based damage index. To investigate the feasibility of the method, fatigue cracks of different sizes were introduced in an aluminum beam subjected to a cyclic load under a three-point bending configuration. The vibration signals corresponding to the healthy and the damaged states of the beam were acquired via piezoceramic sensors. The signals were then processed by the proposed methodology to obtain the damage indices. In addition, for the sake of comparison, the frequency and damping analysis were performed on the test specimen. The results of this study concluded with two major observations. Firstly, the method was highly successful in not only predicting the presence of the fatigue crack, but also in quantifying its progression. Secondly, the proposed energy-based damage index was proved to be superior to the frequency-based methods in terms of sensitivity to the damage detection and quantification. As a result, this technique could be regarded as an efficient non-destructive tool, since it is simple, cost-effective and does not rely on analytical modeling of structures. In addition, the capability of the finite element method (FEM) in mimicking the experiments, and hence for consideration as an effective tool for conducting future parametric studies, was also investigated

  2. Vibration Based Damage Assessment of a Civil Engineering Structures using a Neural Networks

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    In this paper the possibility of using a Multilayer Perceptron (MLP) network trained with the Backpropagation Algorith as a non-destructive damage assessment technique to locate and quantify a damage in Civil Engineering structures is investigated. Since artificial neural networks are proving...

  3. Wireless vibration-based SHM of caisson-type breakwater under foundation damage

    Science.gov (United States)

    Lee, So-Young; Nguyen, Khac-Duy; Kim, Jeong-Tae; Yi, Jin-Hak

    2012-04-01

    This paper presents a vibration-based structural health monitoring (SHM) technique using a high sensitive wireless sensor node for caisson-type breakwater. To achieve the objective, the following approaches are implemented. Firstly, vibration-based SHM method is selected for caisson-type breakwater. The feasibility of the vibration-based SHM method is examined for the caisson structure by FE analysis. Foundation loss damage is considered as the damage of caisson-type breakwater. Secondly, a wireless SHM system with a high sensitive wireless sensor node is designed. The sensor node is built on an imote2 platform. The vibration-based SHM method is embedded on the sensor node. Finally, the performance of the wireless SHM technique is estimated from experimental tests on a lab-scaled caisson. The vibration responses and damage monitoring results are compared with the proposed wireless system and conventional wired system.

  4. Vestas V90-3MW Wind Turbine Gearbox Health Assessment Using a Vibration-Based Condition Monitoring System

    Directory of Open Access Journals (Sweden)

    A. Romero

    2016-01-01

    Full Text Available Reliable monitoring for the early fault diagnosis of gearbox faults is of great concern for the wind industry. This paper presents a novel approach for health condition monitoring (CM and fault diagnosis in wind turbine gearboxes using vibration analysis. This methodology is based on a machine learning algorithm that generates a baseline for the identification of deviations from the normal operation conditions of the turbine and the intrinsic characteristic-scale decomposition (ICD method for fault type recognition. Outliers picked up during the baseline stage are decomposed by the ICD method to obtain the product components which reveal the fault information. The new methodology proposed for gear and bearing defect identification was validated by laboratory and field trials, comparing well with the methods reviewed in the literature.

  5. Compressive power spectrum sensing for vibration-based output-only system identification of structural systems in the presence of noise

    Science.gov (United States)

    Tau Siesakul, Bamrung; Gkoktsi, Kyriaki; Giaralis, Agathoklis

    2015-05-01

    Motivated by the need to reduce monetary and energy consumption costs of wireless sensor networks in undertaking output-only/operational modal analysis of engineering structures, this paper considers a multi-coset analog-toinformation converter for structural system identification from acceleration response signals of white noise excited linear damped structures sampled at sub-Nyquist rates. The underlying natural frequencies, peak gains in the frequency domain, and critical damping ratios of the vibrating structures are estimated directly from the sub-Nyquist measurements and, therefore, the computationally demanding signal reconstruction step is by-passed. This is accomplished by first employing a power spectrum blind sampling (PSBS) technique for multi-band wide sense stationary stochastic processes in conjunction with deterministic non-uniform multi-coset sampling patterns derived from solving a weighted least square optimization problem. Next, modal properties are derived by the standard frequency domain peak picking algorithm. Special attention is focused on assessing the potential of the adopted PSBS technique, which poses no sparsity requirements to the sensed signals, to derive accurate estimates of modal structural system properties from noisy sub- Nyquist measurements. To this aim, sub-Nyquist sampled acceleration response signals corrupted by various levels of additive white noise pertaining to a benchmark space truss structure with closely spaced natural frequencies are obtained within an efficient Monte Carlo simulation-based framework. Accurate estimates of natural frequencies and reasonable estimates of local peak spectral ordinates and critical damping ratios are derived from measurements sampled at about 70% below the Nyquist rate and for SNR as low as 0db demonstrating that the adopted approach enjoys noise immunity.

  6. Vibrational Based Inspection Of A Steel Mast

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    1994-01-01

    The aim of this paper is to present the results from a research project concerning vibrational based inspection of a 20 meter high steel mast containing well defined damages. Introductory analyses dealing with among other things evaluation of potential damage indicators and determination of accep......The aim of this paper is to present the results from a research project concerning vibrational based inspection of a 20 meter high steel mast containing well defined damages. Introductory analyses dealing with among other things evaluation of potential damage indicators and determination...

  7. A search for optimal parameters of resonance circuits ensuring damping of electroelastic structure vibrations based on the solution of natural vibration problem

    Science.gov (United States)

    Oshmarin, D.; Sevodina, N.; Iurlov, M.; Iurlova, N.

    2017-06-01

    In this paper, with the aim of providing passive control of structure vibrations a new approach has been proposed for selecting optimal parameters of external electric shunt circuits connected to piezoelectric elements located on the surface of the structure. The approach is based on the mathematical formulation of the natural vibration problem. The results of solution of this problem are the complex eigenfrequencies, the real part of which represents the vibration frequency and the imaginary part corresponds to the damping ratio, characterizing the rate of damping. A criterion of search for optimal parameters of the external passive shunt circuits, which can provide the system with desired dissipative properties, has been derived based on the analysis of responses of the real and imaginary parts of different complex eigenfrequencies to changes in the values of the parameters of the electric circuit. The efficiency of this approach has been verified in the context of natural vibration problem of rigidly clamped plate and semi-cylindrical shell, which is solved for series-connected and parallel -connected external resonance (consisting of resistive and inductive elements) R-L circuits. It has been shown that at lower (more energy-intensive) frequencies, a series-connected external circuit has the advantage of providing lower values of the circuit parameters, which renders it more attractive in terms of practical applications.

  8. Vibration Based Sun Gear Damage Detection

    Science.gov (United States)

    Hood, Adrian; LaBerge, Kelsen; Lewicki, David; Pines, Darryll

    2013-01-01

    Seeded fault experiments were conducted on the planetary stage of an OH-58C helicopter transmission. Two vibration based methods are discussed that isolate the dynamics of the sun gear from that of the planet gears, bearings, input spiral bevel stage, and other components in and around the gearbox. Three damaged sun gears: two spalled and one cracked, serve as the focus of this current work. A non-sequential vibration separation algorithm was developed and the resulting signals analyzed. The second method uses only the time synchronously averaged data but takes advantage of the signal/source mapping required for vibration separation. Both algorithms were successful in identifying the spall damage. Sun gear damage was confirmed by the presence of sun mesh groups. The sun tooth crack condition was inconclusive.

  9. Structural health monitoring of high voltage electrical switch ceramic insulators in seismic areas

    OpenAIRE

    REBILLAT, Marc; BARTHES, Clément; MECHBAL, Nazih; MOSALAM, Khalid M.

    2014-01-01

    International audience; High voltage electrical switches are crucial components to restart rapidly the electrical network right after an earthquake. But there currently exists no automatic procedure to check if these ceramic insulators have suffered after an earthquake, and there exists no method to recertify a given switch. To deploy a vibration-based structural health monitoring method on ceramic insulators a large shake table able to generate accelerations up to 3 g was used. The idea unde...

  10. Neuro-fuzzy computing for vibration-based damage localization and severity estimation in an experimental wind turbine blade with superimposed operational effects

    Science.gov (United States)

    Hoell, Simon; Omenzetter, Piotr

    2016-04-01

    Fueled by increasing demand for carbon neutral energy, erections of ever larger wind turbines (WTs), with WT blades (WTBs) with higher flexibilities and lower buckling capacities lead to increasing operation and maintenance costs. This can be counteracted with efficient structural health monitoring (SHM), which allows scheduling maintenance actions according to the structural state and preventing dramatic failures. The present study proposes a novel multi-step approach for vibration-based structural damage localization and severity estimation for application in operating WTs. First, partial autocorrelation coefficients (PACCs) are estimated from vibrational responses. Second, principal component analysis is applied to PACCs from the healthy structure in order to calculate scores. Then, the scores are ranked with respect to their ability to differentiate different damage scenarios. This ranking information is used for constructing hierarchical adaptive neuro-fuzzy inference systems (HANFISs), where cross-validation is used to identify optimal numbers of hierarchy levels. Different HANFISs are created for the purposes of structural damage localization and severity estimation. For demonstrating the applicability of the approach, experimental data are superimposed with signals from numerical simulations to account for characteristics of operational noise. For the physical experiments, a small scale WTB is excited with a domestic fan and damage scenarios are introduced non-destructively by attaching small masses. Numerical simulations are also performed for a representative fully functional small WT operating in turbulent wind. The obtained results are promising for future applications of vibration-based SHM to facilitate improved safety and reliability of WTs at lower costs.

  11. Vibration-based damage detection in wind turbine blades using Phase-based Motion Estimation and motion magnification

    Science.gov (United States)

    Sarrafi, Aral; Mao, Zhu; Niezrecki, Christopher; Poozesh, Peyman

    2018-05-01

    Vibration-based Structural Health Monitoring (SHM) techniques are among the most common approaches for structural damage identification. The presence of damage in structures may be identified by monitoring the changes in dynamic behavior subject to external loading, and is typically performed by using experimental modal analysis (EMA) or operational modal analysis (OMA). These tools for SHM normally require a limited number of physically attached transducers (e.g. accelerometers) in order to record the response of the structure for further analysis. Signal conditioners, wires, wireless receivers and a data acquisition system (DAQ) are also typical components of traditional sensing systems used in vibration-based SHM. However, instrumentation of lightweight structures with contact sensors such as accelerometers may induce mass-loading effects, and for large-scale structures, the instrumentation is labor intensive and time consuming. Achieving high spatial measurement resolution for a large-scale structure is not always feasible while working with traditional contact sensors, and there is also the potential for a lack of reliability associated with fixed contact sensors in outliving the life-span of the host structure. Among the state-of-the-art non-contact measurements, digital video cameras are able to rapidly collect high-density spatial information from structures remotely. In this paper, the subtle motions from recorded video (i.e. a sequence of images) are extracted by means of Phase-based Motion Estimation (PME) and the extracted information is used to conduct damage identification on a 2.3-m long Skystream® wind turbine blade (WTB). The PME and phased-based motion magnification approach estimates the structural motion from the captured sequence of images for both a baseline and damaged test cases on a wind turbine blade. Operational deflection shapes of the test articles are also quantified and compared for the baseline and damaged states. In addition

  12. Structural health monitoring feature design by genetic programming

    International Nuclear Information System (INIS)

    Harvey, Dustin Y; Todd, Michael D

    2014-01-01

    Structural health monitoring (SHM) systems provide real-time damage and performance information for civil, aerospace, and other high-capital or life-safety critical structures. Conventional data processing involves pre-processing and extraction of low-dimensional features from in situ time series measurements. The features are then input to a statistical pattern recognition algorithm to perform the relevant classification or regression task necessary to facilitate decisions by the SHM system. Traditional design of signal processing and feature extraction algorithms can be an expensive and time-consuming process requiring extensive system knowledge and domain expertise. Genetic programming, a heuristic program search method from evolutionary computation, was recently adapted by the authors to perform automated, data-driven design of signal processing and feature extraction algorithms for statistical pattern recognition applications. The proposed method, called Autofead, is particularly suitable to handle the challenges inherent in algorithm design for SHM problems where the manifestation of damage in structural response measurements is often unclear or unknown. Autofead mines a training database of response measurements to discover information-rich features specific to the problem at hand. This study provides experimental validation on three SHM applications including ultrasonic damage detection, bearing damage classification for rotating machinery, and vibration-based structural health monitoring. Performance comparisons with common feature choices for each problem area are provided demonstrating the versatility of Autofead to produce significant algorithm improvements on a wide range of problems. (paper)

  13. A review of vibration-based MEMS piezoelectric energy harvesters

    Energy Technology Data Exchange (ETDEWEB)

    Saadon, Salem; Sidek, Othman [Collaborative Microelectronic Design Excellence Center (CEDEC), School of Electrical and Electronic Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Seberang Perai Selatan, Pulau Pinang (Malaysia)

    2011-01-15

    The simplicity associated with the piezoelectric micro-generators makes it very attractive for MEMS applications, especially for remote systems. In this paper we reviewed the work carried out by researchers during the last three years. The improvements in experimental results obtained in the vibration-based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the field of power MEMS in the near future. (author)

  14. An expert system for vibration based diagnostics of rotating machines

    International Nuclear Information System (INIS)

    Korteniemi, A.

    1990-01-01

    Very often changes in the mechanical condition of the rotating machinery can be observed as changes in its vibration. This paper presents an expert system for vibration-based diagnosis of rotating machines by describing the architecture of the developed prototype system. The importance of modelling the problem solving knowledge as well as the domain knowledge is emphasized by presenting the knowledge in several levels

  15. Diagnostic tool for structural health monitoring: effect of material nonlinearity and vibro-impact process

    Science.gov (United States)

    Hiwarkar, V. R.; Babitsky, V. I.; Silberschmidt, V. V.

    2013-07-01

    Numerous techniques are available for monitoring structural health. Most of these techniques are expensive and time-consuming. In this paper, vibration-based techniques are explored together with their use as diagnostic tools for structural health monitoring. Finite-element simulations are used to study the effect of material nonlinearity on dynamics of a cracked bar. Additionally, several experiments are performed to study the effect of vibro-impact behavior of crack on its dynamics. It was observed that a change in the natural frequency of the cracked bar due to crack-tip plasticity and vibro-impact behavior linked to interaction of crack faces, obtained from experiments, led to generation of higher harmonics; this can be used as a diagnostic tool for structural health monitoring.

  16. Vibration Based Diagnosis for Planetary Gearboxes Using an Analytical Model

    Directory of Open Access Journals (Sweden)

    Liu Hong

    2016-01-01

    Full Text Available The application of conventional vibration based diagnostic techniques to planetary gearboxes is a challenge because of the complexity of frequency components in the measured spectrum, which is the result of relative motions between the rotary planets and the fixed accelerometer. In practice, since the fault signatures are usually contaminated by noises and vibrations from other mechanical components of gearboxes, the diagnostic efficacy may further deteriorate. Thus, it is essential to develop a novel vibration based scheme to diagnose gear failures for planetary gearboxes. Following a brief literature review, the paper begins with the introduction of an analytical model of planetary gear-sets developed by the authors in previous works, which can predict the distinct behaviors of fault introduced sidebands. This analytical model is easy to implement because the only prerequisite information is the basic geometry of the planetary gear-set. Afterwards, an automated diagnostic scheme is proposed to cope with the challenges associated with the characteristic configuration of planetary gearboxes. The proposed vibration based scheme integrates the analytical model, a denoising algorithm, and frequency domain indicators into one synergistic system for the detection and identification of damaged gear teeth in planetary gearboxes. Its performance is validated with the dynamic simulations and the experimental data from a planetary gearbox test rig.

  17. Damage Detection with Streamlined Structural Health Monitoring Data

    Directory of Open Access Journals (Sweden)

    Jian Li

    2015-04-01

    Full Text Available The huge amounts of sensor data generated by large scale sensor networks in on-line structural health monitoring (SHM systems often overwhelms the systems’ capacity for data transmission and analysis. This paper presents a new concept for an integrated SHM system in which a streamlined data flow is used as a unifying thread to integrate the individual components of on-line SHM systems. Such an integrated SHM system has a few desirable functionalities including embedded sensor data compression, interactive sensor data retrieval, and structural knowledge discovery, which aim to enhance the reliability, efficiency, and robustness of on-line SHM systems. Adoption of this new concept will enable the design of an on-line SHM system with more uniform data generation and data handling capacity for its subsystems. To examine this concept in the context of vibration-based SHM systems, real sensor data from an on-line SHM system comprising a scaled steel bridge structure and an on-line data acquisition system with remote data access was used in this study. Vibration test results clearly demonstrated the prominent performance characteristics of the proposed integrated SHM system including rapid data access, interactive data retrieval and knowledge discovery of structural conditions on a global level.

  18. Damage detection with streamlined structural health monitoring data.

    Science.gov (United States)

    Li, Jian; Deng, Jun; Xie, Weizhi

    2015-04-15

    The huge amounts of sensor data generated by large scale sensor networks in on-line structural health monitoring (SHM) systems often overwhelms the systems' capacity for data transmission and analysis. This paper presents a new concept for an integrated SHM system in which a streamlined data flow is used as a unifying thread to integrate the individual components of on-line SHM systems. Such an integrated SHM system has a few desirable functionalities including embedded sensor data compression, interactive sensor data retrieval, and structural knowledge discovery, which aim to enhance the reliability, efficiency, and robustness of on-line SHM systems. Adoption of this new concept will enable the design of an on-line SHM system with more uniform data generation and data handling capacity for its subsystems. To examine this concept in the context of vibration-based SHM systems, real sensor data from an on-line SHM system comprising a scaled steel bridge structure and an on-line data acquisition system with remote data access was used in this study. Vibration test results clearly demonstrated the prominent performance characteristics of the proposed integrated SHM system including rapid data access, interactive data retrieval and knowledge discovery of structural conditions on a global level.

  19. Vibration-based condition monitoring industrial, aerospace and automotive applications

    CERN Document Server

    Randall, Robert Bond

    2010-01-01

    ""Without doubt the best modern and up-to-date text on the topic, wirtten by one of the world leading experts in the field. Should be on the desk of any practitioner or researcher involved in the field of Machine Condition Monitoring"" Simon Braun, Israel Institute of Technology Explaining complex ideas in an easy to understand way, Vibration-based Condition Monitoring provides a comprehensive survey of the application of vibration analysis to the condition monitoring of machines. Reflecting the natural progression of these systems by presenting the fundamental material

  20. Structural Health Monitoring under Nonlinear Environmental or Operational Influences

    Directory of Open Access Journals (Sweden)

    Jyrki Kullaa

    2014-01-01

    Full Text Available Vibration-based structural health monitoring is based on detecting changes in the dynamic characteristics of the structure. It is well known that environmental or operational variations can also have an influence on the vibration properties. If these effects are not taken into account, they can result in false indications of damage. If the environmental or operational variations cause nonlinear effects, they can be compensated using a Gaussian mixture model (GMM without the measurement of the underlying variables. The number of Gaussian components can also be estimated. For the local linear components, minimum mean square error (MMSE estimation is applied to eliminate the environmental or operational influences. Damage is detected from the residuals after applying principal component analysis (PCA. Control charts are used for novelty detection. The proposed approach is validated using simulated data and the identified lowest natural frequencies of the Z24 Bridge under temperature variation. Nonlinear models are most effective if the data dimensionality is low. On the other hand, linear models often outperform nonlinear models for high-dimensional data.

  1. Vibration-Based Damage Detection in Beams by Cooperative Coevolutionary Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Kittipong Boonlong

    2014-03-01

    Full Text Available Vibration-based damage detection, a nondestructive method, is based on the fact that vibration characteristics such as natural frequencies and mode shapes of structures are changed when the damage happens. This paper presents cooperative coevolutionary genetic algorithm (CCGA, which is capable for an optimization problem with a large number of decision variables, as the optimizer for the vibration-based damage detection in beams. In the CCGA, a minimized objective function is a numerical indicator of differences between vibration characteristics of the actual damage and those of the anticipated damage. The damage detection in a uniform cross-section cantilever beam, a uniform strength cantilever beam, and a uniform cross-section simply supported beam is used as the test problems. Random noise in the vibration characteristics is also considered in the damage detection. In the simulation analysis, the CCGA provides the superior solutions to those that use standard genetic algorithms presented in previous works, although it uses less numbers of the generated solutions in solution search. The simulation results reveal that the CCGA can efficiently identify the occurred damage in beams for all test problems including the damage detection in a beam with a large number of divided elements such as 300 elements.

  2. A nonlinear multi-mode wideband piezoelectric vibration-based energy harvester using compliant orthoplanar spring

    Energy Technology Data Exchange (ETDEWEB)

    Dhote, Sharvari, E-mail: sharvari.dhote@mail.utoronto.ca; Zu, Jean; Zhu, Yang [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King' s College Road, Toronto, Ontario M5S-3G8 (Canada)

    2015-04-20

    In this paper, a nonlinear wideband multi-mode piezoelectric vibration-based energy harvester (PVEH) is proposed based on a compliant orthoplanar spring (COPS), which has an advantage of providing multiple vibration modes at relatively low frequencies. The PVEH is made of a tri-leg COPS flexible structure, where three fixed-guided beams are capable of generating strong nonlinear oscillations under certain base excitation. A prototype harvester was fabricated and investigated through both finite-element analysis and experiments. The frequency response shows multiple resonance which corresponds to a hardening type of nonlinear resonance. By adding masses at different locations on the COPS structure, the first three vibration modes are brought close to each other, where the three hardening nonlinear resonances provide a wide bandwidth for the PVEH. The proposed PVEH has enhanced performance of the energy harvester in terms of a wide frequency bandwidth and a high-voltage output under base excitations.

  3. Effect of material constants on power output in piezoelectric vibration-based generators.

    Science.gov (United States)

    Takeda, Hiroaki; Mihara, Kensuke; Yoshimura, Tomohiro; Hoshina, Takuya; Tsurumi, Takaaki

    2011-09-01

    A possible power output estimation based on material constants in piezoelectric vibration-based generators is proposed. A modified equivalent circuit model of the generator was built and was validated by the measurement results in the generator fabricated using potassium sodium niobate-based and lead zirconate titanate (PZT) ceramics. Subsequently, generators with the same structure using other PZT-based and bismuth-layered structure ferroelectrics ceramics were fabricated and tested. The power outputs of these generators were expressed as a linear functions of the term composed of electromechanical coupling coefficients k(sys)(2) and mechanical quality factors Q*(m) of the generator. The relationship between device constants (k(sys)(2) and Q*(m)) and material constants (k(31)(2) and Q(m)) was clarified. Estimation of the power output using material constants is demonstrated and the appropriate piezoelectric material for the generator is suggested.

  4. Vibration-Based Damage Identification in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Tcherniak, Dmitri; Damkilde, Lars

    Due to the existing trend of placing wind turbines in impassable terrain, for example, offshore, these structures constitute prime candidates for being subjected to structural health monitoring (SHM). The wind turbine blades have in particular been paid research attention [1] as these compose one...... of the most common and critical components to fail in the turbines [2]. The standard structural integrity assessment of blades is based on visual inspection, which requires the turbine in question to be stopped while inspections are conducted. This procedure is extremely costly and tedious, hence emphasizing...

  5. Structural health monitoring for ship structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Angel, Marian [Los Alamos National Laboratory; Bement, Matthew [Los Alamos National Laboratory; Salvino, Liming [NSWC, CADEROCK

    2009-01-01

    Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

  6. High Frequency Vibration Based Fatigue Testing of Developmental Alloys

    Science.gov (United States)

    Holycross, Casey M.; Srinivasan, Raghavan; George, Tommy J.; Tamirisakandala, Seshacharyulu; Russ, Stephan M.

    Many fatigue test methods have been previously developed to rapidly evaluate fatigue behavior. This increased test speed can come at some expense, since these methods may require non-standard specimen geometry or increased facility and equipment capability. One such method, developed by George et al, involves a base-excited plate specimen driven into a high frequency bending resonant mode. This resonant mode is of sufficient frequency (typically 1200 to 1700 Hertz) to accumulate 107 cycles in a few hours. One of the main limitations of this test method is that fatigue cracking is almost certainly guaranteed to be surface initiated at regions of high stress. This brings into question the validity of the fatigue test results, as compared to more traditional uniaxial, smooth-bar testing, since high stresses are subjecting only a small volume to fatigue damage. This limitation also brings into question the suitability of this method to screen developmental alloys, should their initiation life be governed by subsurface flaws. However, if applicable, the rapid generation of fatigue data using this method would facilitate faster design iterations, identifying more quickly, material and manufacturing process deficiencies. The developmental alloy used in this study was a powder metallurgy boron-modified Ti-6Al-4V, a new alloy currently being considered for gas turbine engine fan blades. Plate specimens were subjected to fully reversed bending fatigue. Results are compared with existing data from commercially available Ti-6Al-4V using both vibration based and more traditional fatigue test methods.

  7. Vibration-based monitoring and diagnostics using compressive sensing

    Science.gov (United States)

    Ganesan, Vaahini; Das, Tuhin; Rahnavard, Nazanin; Kauffman, Jeffrey L.

    2017-04-01

    Vibration data from mechanical systems carry important information that is useful for characterization and diagnosis. Standard approaches rely on continually streaming data at a fixed sampling frequency. For applications involving continuous monitoring, such as Structural Health Monitoring (SHM), such approaches result in high volume data and rely on sensors being powered for prolonged durations. Furthermore, for spatial resolution, structures are instrumented with a large array of sensors. This paper shows that both volume of data and number of sensors can be reduced significantly by applying Compressive Sensing (CS) in vibration monitoring applications. The reduction is achieved by using random sampling and capitalizing on the sparsity of vibration signals in the frequency domain. Preliminary experimental results validating CS-based frequency recovery are also provided. By exploiting the sparsity of mode shapes, CS can also enable efficient spatial reconstruction using fewer spatially distributed sensors. CS can thereby reduce the cost and power requirement of sensing as well as streamline data storage and processing in monitoring applications. In well-instrumented structures, CS can enable continued monitoring in case of sensor or computational failures.

  8. Improved vibration-based energy harvesting by annular mass configuration of piezoelectric circular diaphragms

    Science.gov (United States)

    Yang, Yangyiwei; Li, Yuanbo; Guo, Yaqian; Xu, Bai-Xiang; Yang, Tongqing

    2018-03-01

    Vibration-based energy harvesting using piezoelectric circular diaphragms (PCDs) with a structure featuring the central mass (C-mass) configuration has drawn much attention in recent decades. In this work, we propose a new configuration with the annular proof mass (A-mass) where an improved energy harvesting is promised. The numerical analysis was employed using the circuit-coupled piezoelectric simulation, and the experimental validation was implemented using PCDs with the even-width annular electrodes. Samples with the different mass configurations as well as structural parameters ϖ 1 and ϖ 2, which indicate the ratio between the inner boundary radius and piezoelectric ceramic radius as well as the ratio between outer boundary radius and the substrate radius, respectively, were prepared and tested. The impedance-matched output power of full-electrode PCDs was also collected, and some distinct improvement was measured on samples with the certain structural parameters. The power increases from 14.1 mW to 19.0 mW after changing the configuration from C-mass to A-mass with the same parameters (ϖ 1, ϖ 2) = (0.16, 0.9), showing the considerable improvement in energy harvesting by using A-mass configuration.

  9. New Sensors and Techniques for the Structural Health Monitoring of Propulsion Systems

    Directory of Open Access Journals (Sweden)

    Mark Woike

    2013-01-01

    Full Text Available The ability to monitor the structural health of the rotating components, especially in the hot sections of turbine engines, is of major interest to aero community in improving engine safety and reliability. The use of instrumentation for these applications remains very challenging. It requires sensors and techniques that are highly accurate, are able to operate in a high temperature environment, and can detect minute changes and hidden flaws before catastrophic events occur. The National Aeronautics and Space Administration (NASA, through the Aviation Safety Program (AVSP, has taken a lead role in the development of new sensor technologies and techniques for the in situ structural health monitoring of gas turbine engines. This paper presents a summary of key results and findings obtained from three different structural health monitoring approaches that have been investigated. This includes evaluating the performance of a novel microwave blade tip clearance sensor; a vibration based crack detection technique using an externally mounted capacitive blade tip clearance sensor; and lastly the results of using data driven anomaly detection algorithms for detecting cracks in a rotating disk.

  10. Sequential projection pursuit for optimised vibration-based damage detection in an experimental wind turbine blade

    Science.gov (United States)

    Hoell, Simon; Omenzetter, Piotr

    2018-02-01

    To advance the concept of smart structures in large systems, such as wind turbines (WTs), it is desirable to be able to detect structural damage early while using minimal instrumentation. Data-driven vibration-based damage detection methods can be competitive in that respect because global vibrational responses encompass the entire structure. Multivariate damage sensitive features (DSFs) extracted from acceleration responses enable to detect changes in a structure via statistical methods. However, even though such DSFs contain information about the structural state, they may not be optimised for the damage detection task. This paper addresses the shortcoming by exploring a DSF projection technique specialised for statistical structural damage detection. High dimensional initial DSFs are projected onto a low-dimensional space for improved damage detection performance and simultaneous computational burden reduction. The technique is based on sequential projection pursuit where the projection vectors are optimised one by one using an advanced evolutionary strategy. The approach is applied to laboratory experiments with a small-scale WT blade under wind-like excitations. Autocorrelation function coefficients calculated from acceleration signals are employed as DSFs. The optimal numbers of projection vectors are identified with the help of a fast forward selection procedure. To benchmark the proposed method, selections of original DSFs as well as principal component analysis scores from these features are additionally investigated. The optimised DSFs are tested for damage detection on previously unseen data from the healthy state and a wide range of damage scenarios. It is demonstrated that using selected subsets of the initial and transformed DSFs improves damage detectability compared to the full set of features. Furthermore, superior results can be achieved by projecting autocorrelation coefficients onto just a single optimised projection vector.

  11. Structural health monitoring for DOT using magnetic shape memory alloy cables in concrete

    Science.gov (United States)

    Davis, Allen; Mirsayar, Mirmilad; Sheahan, Emery; Hartl, Darren

    2018-03-01

    Embedding shape memory alloy (SMA) wires in concrete components offers the potential to monitor their structural health via external magnetic field sensing. Currently, structural health monitoring (SHM) is dominated by acoustic emission and vibration-based methods. Thus, it is attractive to pursue alternative damage sensing techniques that may lower the cost or increase the accuracy of SHM. In this work, SHM via magnetic field detection applied to embedded magnetic shape memory alloy (MSMA) is demonstrated both experimentally and using computational models. A concrete beam containing iron-based MSMA wire is subjected to a 3-point bend test where structural damage is induced, thereby resulting in a localized phase change of the MSMA wire. Magnetic field lines passing through the embedded MSMA domain are altered by this phase change and can thus be used to detect damage within the structure. A good correlation is observed between the computational and experimental results. Additionally, the implementation of stranded MSMA cables in place of the MSMA wire is assessed through similar computational models. The combination of these computational models and their subsequent experimental validation provide sufficient support for the feasibility of SHM using magnetic field sensing via MSMA embedded components.

  12. The Vibration Based Fatigue Damage Assessment of Steel and Steel Fiber Reinforced Concrete (SFRC Composite Girder

    Directory of Open Access Journals (Sweden)

    Xu Chen

    2015-01-01

    Full Text Available The steel-concrete composite girder has been usually applied in the bridge and building structures, mostly consisting of concrete slab, steel girder, and shear connector. The current fatigue damage assessment for the composite girder is largely based on the strain values and concrete crack features, which is time consuming and not stable. Hence the vibration-based fatigue damage assessment has been considered in this study. In detail, a steel-steel fiber reinforced concrete (SFRC composite girder was tested. The steel fiber reinforced concrete is usually considered for dealing with the concrete cracks in engineering practice. The composite girder was 3.3m long and 0.45m high. The fatigue load and impact excitation were applied on the specimen sequentially. According to the test results, the concrete crack development and global stiffness degradation during the fatigue test were relatively slow due to the favourable performance of SFRC in tension. But on the other hand, the vibration features varied significantly during the fatigue damage development. Generally, it confirmed the feasibility of executing fatigue damage assessment of composite bridge based on vibration method.

  13. Structural Health Monitoring for Impact Damage in Composite Structures.

    Energy Technology Data Exchange (ETDEWEB)

    Roach, Dennis P.; Raymond Bond (Purdue); Doug Adams (Purdue)

    2014-08-01

    Composite structures are increasing in prevalence throughout the aerospace, wind, defense, and transportation industries, but the many advantages of these materials come with unique challenges, particularly in inspecting and repairing these structures. Because composites of- ten undergo sub-surface damage mechanisms which compromise the structure without a clear visual indication, inspection of these components is critical to safely deploying composite re- placements to traditionally metallic structures. Impact damage to composites presents one of the most signi fi cant challenges because the area which is vulnerable to impact damage is generally large and sometimes very dif fi cult to access. This work seeks to further evolve iden- ti fi cation technology by developing a system which can detect the impact load location and magnitude in real time, while giving an assessment of the con fi dence in that estimate. Fur- thermore, we identify ways by which impact damage could be more effectively identi fi ed by leveraging impact load identi fi cation information to better characterize damage. The impact load identi fi cation algorithm was applied to a commercial scale wind turbine blade, and results show the capability to detect impact magnitude and location using a single accelerometer, re- gardless of sensor location. A technique for better evaluating the uncertainty of the impact estimates was developed by quantifying how well the impact force estimate meets the assump- tions underlying the force estimation technique. This uncertainty quanti fi cation technique was found to reduce the 95% con fi dence interval by more than a factor of two for impact force estimates showing the least uncertainty, and widening the 95% con fi dence interval by a fac- tor of two for the most uncertain force estimates, avoiding the possibility of understating the uncertainty associated with these estimates. Linear vibration based damage detection tech- niques were investigated in the

  14. Adaptive Technology Application for Vibration-Based Diagnostics of Roller Bearings on Industrial Plants

    Directory of Open Access Journals (Sweden)

    Mironov Aleksey

    2014-09-01

    Full Text Available Roller bearings are widely used in equipment of different applications; therefore, the issues related to the assessment of bearing technical state and localization of bearing faults are quite important and relevant. The reason is that technical state of a bearing is a critical component, which determines efficiency of a mechanism or equipment. For bearings inspection and diagnostics, various methods of vibration-based diagnostics are used. The adaptive technology for vibration-based diagnostics developed in „D un D centrs” is an effective tool for evaluation of technical state of bearings in operation compared to the existing SKF method.

  15. Development of Vibration-Based Piezoelectric Raindrop Energy Harvesting System

    Science.gov (United States)

    Wong, Chin Hong; Dahari, Zuraini

    2017-03-01

    The trend of finding new means to harvest energy has triggered numerous researches to explore the potential of raindrop energy harvesting. This paper presents an investigation on raindrop energy harvesting which compares the performance of polyvinylidene fluoride (PVDF) cantilever and bridge structure transducers and the development of a raindrop energy harvesting system. The parameters which contribute to the output voltage such as droplet size, droplets released at specific heights and dimensions of PVDF transducers are analyzed. Based on the experimental results, the outcomes have shown that the bridge structure transducer generated a higher voltage than the cantilever. Several dimensions have been tested and it was found that the 30 mm × 4 mm × 25 μm bridge structure transducer generated a relatively high AC open-circuit voltage, which is 4.22 V. The power generated by the bridge transducer is 18 μW across a load of 330 kΩ. The transducer is able to drive up a standard alternative current (AC) to direct current (DC) converter (full-wave bridge rectifier). It generated a DC voltage, V DC of 8.7 mV and 229 pW across a 330 kΩ resistor per drop. It is also capable to generate 9.3 nJ in 20 s from an actual rain event.

  16. Virtual standards of vibration-based defects diagnostics in railway industry

    Directory of Open Access Journals (Sweden)

    Vladimir TETTER

    2009-01-01

    Full Text Available The issues related to testing the functionality stated by producers of vibration-based diagnostic equipment have been considered. The introduction of virtual standards of defects found in bearing and geared assemblies of rolling stock is offered. The variants of virtual standards realization have been considered.

  17. Integrated vibration-based maintenance: an approach for continuous reduction in LCC. A case study

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, B. [ER Konsult Utveckling AB, Vaexjoe (Sweden)

    1998-12-31

    The biggest thread in achieving and maintaining high equipment effectiveness can be stated as: whether the improved manufacturing processes capable of producing quality products at a competitive cost. The effect of a new vibration-based maintenance concept, called Total Quality Maintenance (TQMain), is introduced. It aims to make intensive use of the real-time data acquisition and analysis to detect causes behind product quality deviation and failures in machinery, and following defect development at an early stage to increase machine mean effective life and improve company`s economics. The effect of TQMain on LCC of machinery and company`s economics is discussed. A case study to reveal savings in maintenance cost when a vibration-based policy involved, is presented. Using TQMain, company`s economics can be improved effectively through continuous improvement of the technical and economic effectiveness of production processes. (orig.) 14 refs.

  18. Integrated vibration-based maintenance: an approach for continuous reduction in LCC. A case study

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, B [ER Konsult Utveckling AB, Vaexjoe (Sweden)

    1999-12-31

    The biggest thread in achieving and maintaining high equipment effectiveness can be stated as: whether the improved manufacturing processes capable of producing quality products at a competitive cost. The effect of a new vibration-based maintenance concept, called Total Quality Maintenance (TQMain), is introduced. It aims to make intensive use of the real-time data acquisition and analysis to detect causes behind product quality deviation and failures in machinery, and following defect development at an early stage to increase machine mean effective life and improve company`s economics. The effect of TQMain on LCC of machinery and company`s economics is discussed. A case study to reveal savings in maintenance cost when a vibration-based policy involved, is presented. Using TQMain, company`s economics can be improved effectively through continuous improvement of the technical and economic effectiveness of production processes. (orig.) 14 refs.

  19. Structural health monitoring using wireless sensor networks

    Science.gov (United States)

    Sreevallabhan, K.; Nikhil Chand, B.; Ramasamy, Sudha

    2017-11-01

    Monitoring and analysing health of large structures like bridges, dams, buildings and heavy machinery is important for safety, economical, operational, making prior protective measures, and repair and maintenance point of view. In recent years there is growing demand for such larger structures which in turn make people focus more on safety. By using Microelectromechanical Systems (MEMS) Accelerometer we can perform Structural Health Monitoring by studying the dynamic response through measure of ambient vibrations and strong motion of such structures. By using Wireless Sensor Networks (WSN) we can embed these sensors in wireless networks which helps us to transmit data wirelessly thus we can measure the data wirelessly at any remote location. This in turn reduces heavy wiring which is a cost effective as well as time consuming process to lay those wires. In this paper we developed WSN based MEMS-accelerometer for Structural to test the results in the railway bridge near VIT University, Vellore campus.

  20. Structural health monitoring 2012. Proceedings. Vol. 1

    International Nuclear Information System (INIS)

    Boller, Christian

    2012-01-01

    Structural Health Monitoring (SHM) is an emerging technology, dealing with the development and implementation of techniques and systems where monitoring, inspection and damage detection become an integral part of structures and thus a matter of automation. It further merges with a variety of techniques related to diagnostics and prognostics. SHM emerged from the field of smart structures and laterally encompasses disciplines such as structural dynamics, materials and structures, fatigue and fracture, non-destructive testing and evaluation, sensors and actuators, microelectronics, signal processing and much more. To be effective in the development of SHM systems, a multidisciplinary approach is therefore required. Without this global view it will be difficult for engineers to holistically manage the operation of an engineering structure through its life cycle in the future and to generate new breakthroughs in structural engineering. The first volume of the proceedings contains topics dealing with physics, materials and sensors. Five of the contributions are separately analyzed for the ENERGY database.

  1. New trends in structural health monitoring

    CERN Document Server

    Güemes, J

    2013-01-01

    Experts actively working in structural health monitoring and control techniques present the current research, areas of application and tendencies for the future of this technology, including various design issues involved. Examples using some of the latest hardware and software tools, experimental data from small scale laboratory demonstrators and measurements made on real structures illustrate the book. It will be a reference for professionals and students in the areas of engineering, applied natural sciences and engineering management.

  2. Structural health monitoring 2012. Proceedings. Vol. 2

    International Nuclear Information System (INIS)

    Boller, Christian

    2012-01-01

    Structural Health Monitoring (SHM) is an emerging technology, dealing with the development and implementation of techniques and systems where monitoring, inspection and damage detection become an integral part of structures and thus a matter of automation. It further merges with a variety of techniques related to diagnostics and prognostics. SHM emerged from the field of smart structures and laterally encompasses disciplines such as structural dynamics, materials and structures, fatigue and fracture, non-destructive testing and evaluation, sensors and actuators, microelectronics, signal processing and much more. To be effective in the development of SHM systems, a multidisciplinary approach is therefore required. Without this global view it will be difficult for engineers to holistically manage the operation of an engineering structure through its life cycle in the future and to generate new breakthroughs in structural engineering. The second volume of the proceedings contains topics dealing with applications in the field of aeronautics, astronautic, civil engineering (bridges), energy (wind power), structural health monitoring (transportation), and poster presentations. Ten of the contributions are separately analyzed for the ENERGY database.

  3. Thermoelastic Damping in FGM Nano-Electromechanical System in Axial Vibration Based on Eringen Nonlocal Theory

    Science.gov (United States)

    Rahimi, Z.; Rashahmadi, S.

    2017-11-01

    The thermo-elastic damping is a dominant source of internal damping in micro-electromechanical systems (MEMS) and nano-electromechanical systems (NEMS). The internal damping cannot neither be controlled nor minimized unless either mechanical or geometrical properties are changed. Therefore, a novel FGMNEM system with a controllable thermo-elastic damping of axial vibration based on Eringen nonlocal theory is considered. The effects of different parameter like the gradient index, nonlocal parameter, length of nanobeam and ambient temperature on the thermo-elastic damping quality factor are presented. It is shown that the thermo-elastic damping can be controlled by changing different parameter.

  4. Governance structures impact on eHealth

    DEFF Research Database (Denmark)

    Kierkegaard, Patrick

    2015-01-01

    Background National eHealth implementation efforts need to move beyond the scope of making technology the primary focus and instead consider the broader spectrum of influences that can either hinder or facilitate eHealth adoption such as governance structures and policies. In this study, Denmark...... serves as an ideal candidate for further examination due to the country׳s rich history of intertwining events that have played an important role in the dynamic relationship between governance and eHealth success and failures. Methods A case study approach was used to gather a combination of primary...... and secondary data sources. All data collection was carried out through desk-research. Data collection relied on performing an extensive search of literature for relevant studies using combinations of keywords that reflected eHealth and governance-related topics. Inclusion and exclusion criteria׳s were applied...

  5. Frequency Selective Surface for Structural Health Monitoring

    Science.gov (United States)

    Norlyana Azemi, Saidatul; Mustaffa, Farzana Hazira Wan; Faizal Jamlos, Mohd; Abdullah Al-Hadi, Azremi; Soh, Ping Jack

    2018-03-01

    Structural health monitoring (SHM) technologies have attained attention to monitor civil structures. SHM sensor systems have been used in various civil structures such as bridges, buildings, tunnels and so on. However the previous sensor for SHM is wired and encounter with problem to cover large areas. Therefore, wireless sensor was introduced for SHM to reduce network connecting problem. Wireless sensors for Structural Health monitoring are new technology and have many advantages to overcome the drawback of conventional and wired sensor. This project proposed passive wireless SHM sensor using frequency selective surface (FSS) as an alternative to conventional sensors. The electromagnetic wave characteristic of FSS will change by geometrical changes of FSS due to mechanical strain or structural failure. The changes feature is used as a sensing function without any connecting wires. Two type of design which are circular ring and square loop along with the transmission and reflection characteristics of SHM using FSS were discussed in this project. A simulation process has shown that incident angle characteristics can be use as a data for SHM application.

  6. Assessing the value of structural health monitoring

    DEFF Research Database (Denmark)

    Thöns, S.; Faber, Michael Havbro

    2013-01-01

    Structural Health Monitoring (SHM) systems are designed for assisting owners and operators with information and forecasts concerning the fitness for purpose of structures and building systems. The benefit associated with the implementation of SHM may in some cases be intuitively anticipated...... as their responses and performances over their life-cycle. In addition, the quality of monitoring and the performance of possible remedial actions triggered by monitoring results are modeled probabilistically.The consequences accounted for, in principle include all consequences associated with the performance...

  7. Development of a cost-effective and flexible vibration DAQ system for long-term continuous structural health monitoring

    Science.gov (United States)

    Nguyen, Theanh; Chan, Tommy H. T.; Thambiratnam, David P.; King, Les

    2015-12-01

    In the structural health monitoring (SHM) field, long-term continuous vibration-based monitoring is becoming increasingly popular as this could keep track of the health status of structures during their service lives. However, implementing such a system is not always feasible due to on-going conflicts between budget constraints and the need of sophisticated systems to monitor real-world structures under their demanding in-service conditions. To address this problem, this paper presents a comprehensive development of a cost-effective and flexible vibration DAQ system for long-term continuous SHM of a newly constructed institutional complex with a special focus on the main building. First, selections of sensor type and sensor positions are scrutinized to overcome adversities such as low-frequency and low-level vibration measurements. In order to economically tackle the sparse measurement problem, a cost-optimized Ethernet-based peripheral DAQ model is first adopted to form the system skeleton. A combination of a high-resolution timing coordination method based on the TCP/IP command communication medium and a periodic system resynchronization strategy is then proposed to synchronize data from multiple distributed DAQ units. The results of both experimental evaluations and experimental-numerical verifications show that the proposed DAQ system in general and the data synchronization solution in particular work well and they can provide a promising cost-effective and flexible alternative for use in real-world SHM projects. Finally, the paper demonstrates simple but effective ways to make use of the developed monitoring system for long-term continuous structural health evaluation as well as to use the instrumented building herein as a multi-purpose benchmark structure for studying not only practical SHM problems but also synchronization related issues.

  8. Acoustic Techniques for Structural Health Monitoring

    Science.gov (United States)

    Frankenstein, B.; Augustin, J.; Hentschel, D.; Schubert, F.; Köhler, B.; Meyendorf, N.

    2008-02-01

    Future safety and maintenance strategies for industrial components and vehicles are based on combinations of monitoring systems that are permanently attached to or embedded in the structure, and periodic inspections. The latter belongs to conventional nondestructive evaluation (NDE) and can be enhanced or partially replaced by structural health monitoring systems. However, the main benefit of this technology for the future will consist of systems that can be differently designed based on improved safety philosophies, including continuous monitoring. This approach will increase the efficiency of inspection procedures at reduced inspection times. The Fraunhofer IZFP Dresden Branch has developed network nodes, miniaturized transmitter and receiver systems for active and passive acoustical techniques and sensor systems that can be attached to or embedded into components or structures. These systems have been used to demonstrate intelligent sensor networks for the monitoring of aerospace structures, railway systems, wind energy generators, piping system and other components. Material discontinuities and flaws have been detected and monitored during full scale fatigue testing. This paper will discuss opportunities and future trends in nondestructive evaluation and health monitoring based on new sensor principles and advanced microelectronics. It will outline various application examples of monitoring systems based on acoustic techniques and will indicate further needs for research and development.

  9. Meanings of health: interrogating structure and culture.

    Science.gov (United States)

    Dutta, Mohan Jyoti; Basu, Ambar

    2008-11-01

    Based on the argument that context ought to be centralized in discourses of health communication, this article applies the culture-centered approach to engage in dialogue about issues of health with 18 men in rural West Bengal. The culture-centered approach is based on dialogue between the researcher and the community members, with the goals of listening to the voices of cultural members in suggesting culture-based health solutions. In this project, our discursive engagement with the participants suggests that health is primarily constructed as an absence, framed in the realm of minimal access to healthcare resources. In a situation where the resources are limited, the participants discussed the importance of trust in their relationship with the local provider. Health was also seen as a collective resource that was both an asset of the collective and a responsibility of the collective. Finally, the participants also pointed out the ways in which corruption in the structure introduced a paradox in policy discourse and the material conditions of the participants.

  10. On the Nonlinear Behavior of the Piezoelectric Coupling on Vibration-Based Energy Harvesters

    Directory of Open Access Journals (Sweden)

    Luciana L. Silva

    2015-01-01

    Full Text Available Vibration-based energy harvesting with piezoelectric elements has an increasing importance nowadays being related to numerous potential applications. A wide range of nonlinear effects is observed in energy harvesting devices and the analysis of the power generated suggests that they have considerable influence on the results. Linear constitutive models for piezoelectric materials can provide inconsistencies on the prediction of the power output of the energy harvester, mainly close to resonant conditions. This paper investigates the effect of the nonlinear behavior of the piezoelectric coupling. A one-degree of freedom mechanical system is coupled to an electrical circuit by a piezoelectric element and different coupling models are investigated. Experimental tests available in the literature are employed as a reference establishing the best matches of the models. Subsequently, numerical simulations are carried out showing different responses of the system indicating that nonlinear piezoelectric couplings can strongly modify the system dynamics.

  11. Active vibration-based SHM system: demonstration on an operating Vestas V27 wind turbine

    DEFF Research Database (Denmark)

    Tcherniak, Dmitri; Mølgaard, Lasse Lohilahti

    2016-01-01

    with the system and a 3.5 month monitoring campaign was conducted while the turbine was operating normally. During the campaign, a defect – a trailing edge opening – was artificially introduced into the blade and its size was gradually increased from the original 15 cm to 45 cm. Using an unsupervised learning......This study presents a system that is able to detect defects like cracks, leading/trailing edge opening or delamination of at least 15 cm size, remotely, without stopping the wind turbine. The system is vibration-based: mechanical energy is artificially introduced by means of an electromechanical......-to-noise ratio. At the same time, the corresponding wavelength is short enough to deliver required damage detection resolution and long enough to be able to propagate the entire blade length. The paper demonstrates the system on a 225 kW Vesta s V27 wind turbine. One blade of the wind turbine was equipped...

  12. Vibration-based Energy Harvesting Systems Characterization Using Automated Electronic Equipment

    Directory of Open Access Journals (Sweden)

    Ioannis KOSMADAKIS

    2015-04-01

    Full Text Available A measurement bench has been developed to fully automate the procedure for the characterization of a vibration-based energy scavenging system. The measurement system is capable of monitoring all important characteristics of a vibration harvesting system (input and output voltage, current, and other parameters, frequency and acceleration values, etc.. It is composed of a PC, typical digital measuring instruments (oscilloscope, waveform generator, etc., certain sensors and actuators, along with a microcontroller based automation module. The automation of the procedure and the manipulation of the acquired data are performed by LabVIEW software. Typical measurements of a system consisting of a vibrating source, a vibration transducer and an active rectifier are presented.

  13. Feedback on the Surveillance 8 challenge: Vibration-based diagnosis of a Safran aircraft engine

    Science.gov (United States)

    Antoni, Jérôme; Griffaton, Julien; André, Hugo; Avendaño-Valencia, Luis David; Bonnardot, Frédéric; Cardona-Morales, Oscar; Castellanos-Dominguez, German; Daga, Alessandro Paolo; Leclère, Quentin; Vicuña, Cristián Molina; Acuña, David Quezada; Ompusunggu, Agusmian Partogi; Sierra-Alonso, Edgar F.

    2017-12-01

    This paper presents the content and outcomes of the Safran contest organized during the International Conference Surveillance 8, October 20-21, 2015, at the Roanne Institute of Technology, France. The contest dealt with the diagnosis of a civil aircraft engine based on vibration data measured in a transient operating mode and provided by Safran. Based on two independent exercises, the contest offered the possibility to benchmark current diagnostic methods on real data supplemented with several challenges. Outcomes of seven competing teams are reported and discussed. The object of the paper is twofold. It first aims at giving a picture of the current state-of-the-art in vibration-based diagnosis of rolling-element bearings in nonstationary operating conditions. Second, it aims at providing the scientific community with a benchmark and some baseline solutions. In this respect, the data used in the contest are made available as supplementary material.

  14. Structural health monitoring of wind turbine blades

    Science.gov (United States)

    Rumsey, Mark A.; Paquette, Joshua A.

    2008-03-01

    As electric utility wind turbines increase in size, and correspondingly, increase in initial capital investment cost, there is an increasing need to monitor the health of the structure. Acquiring an early indication of structural or mechanical problems allows operators to better plan for maintenance, possibly operate the machine in a de-rated condition rather than taking the unit off-line, or in the case of an emergency, shut the machine down to avoid further damage. This paper describes several promising structural health monitoring (SHM) techniques that were recently exercised during a fatigue test of a 9 meter glass-epoxy and carbon-epoxy wind turbine blade. The SHM systems were implemented by teams from NASA Kennedy Space Center, Purdue University and Virginia Tech. A commercial off-the-shelf acoustic emission (AE) NDT system gathered blade AE data throughout the test. At a fatigue load cycle rate around 1.2 Hertz, and after more than 4,000,000 fatigue cycles, the blade was diagnostically and visibly failing at the out-board blade spar-cap termination point at 4.5 meters. For safety reasons, the test was stopped just before the blade completely failed. This paper provides an overview of the SHM and NDT system setups and some current test results.

  15. Information processing for aerospace structural health monitoring

    Science.gov (United States)

    Lichtenwalner, Peter F.; White, Edward V.; Baumann, Erwin W.

    1998-06-01

    Structural health monitoring (SHM) technology provides a means to significantly reduce life cycle of aerospace vehicles by eliminating unnecessary inspections, minimizing inspection complexity, and providing accurate diagnostics and prognostics to support vehicle life extension. In order to accomplish this, a comprehensive SHM system will need to acquire data from a wide variety of diverse sensors including strain gages, accelerometers, acoustic emission sensors, crack growth gages, corrosion sensors, and piezoelectric transducers. Significant amounts of computer processing will then be required to convert this raw sensor data into meaningful information which indicates both the diagnostics of the current structural integrity as well as the prognostics necessary for planning and managing the future health of the structure in a cost effective manner. This paper provides a description of the key types of information processing technologies required in an effective SHM system. These include artificial intelligence techniques such as neural networks, expert systems, and fuzzy logic for nonlinear modeling, pattern recognition, and complex decision making; signal processing techniques such as Fourier and wavelet transforms for spectral analysis and feature extraction; statistical algorithms for optimal detection, estimation, prediction, and fusion; and a wide variety of other algorithms for data analysis and visualization. The intent of this paper is to provide an overview of the role of information processing for SHM, discuss various technologies which can contribute to accomplishing this role, and present some example applications of information processing for SHM implemented at the Boeing Company.

  16. Data driven innovations in structural health monitoring

    Science.gov (United States)

    Rosales, M. J.; Liyanapathirana, R.

    2017-05-01

    At present, substantial investments are being allocated to civil infrastructures also considered as valuable assets at a national or global scale. Structural Health Monitoring (SHM) is an indispensable tool required to ensure the performance and safety of these structures based on measured response parameters. The research to date on damage assessment has tended to focus on the utilization of wireless sensor networks (WSN) as it proves to be the best alternative over the traditional visual inspections and tethered or wired counterparts. Over the last decade, the structural health and behaviour of innumerable infrastructure has been measured and evaluated owing to several successful ventures of implementing these sensor networks. Various monitoring systems have the capability to rapidly transmit, measure, and store large capacities of data. The amount of data collected from these networks have eventually been unmanageable which paved the way to other relevant issues such as data quality, relevance, re-use, and decision support. There is an increasing need to integrate new technologies in order to automate the evaluation processes as well as to enhance the objectivity of data assessment routines. This paper aims to identify feasible methodologies towards the application of time-series analysis techniques to judiciously exploit the vast amount of readily available as well as the upcoming data resources. It continues the momentum of a greater effort to collect and archive SHM approaches that will serve as data-driven innovations for the assessment of damage through efficient algorithms and data analytics.

  17. Integrating structural health and condition monitoring

    DEFF Research Database (Denmark)

    May, Allan; Thöns, Sebastian; McMillan, David

    2015-01-01

    window’ allowing for the possible detection of faults up to 6 months in advance. The SHM system model uses a reduction in the probability of failure factor to account for lower modelling uncertainties. A case study is produced that shows a reduction in operating costs and also a reduction in risk......There is a large financial incentive to minimise operations and maintenance (O&M) costs for offshore wind power by optimising the maintenance plan. The integration of condition monitoring (CM) and structural health monitoring (SHM) may help realise this. There is limited work on the integration...

  18. Identification methods for structural health monitoring

    CERN Document Server

    Papadimitriou, Costas

    2016-01-01

    The papers in this volume provide an introduction to well known and established system identification methods for structural health monitoring and to more advanced, state-of-the-art tools, able to tackle the challenges associated with actual implementation. Starting with an overview on fundamental methods, introductory concepts are provided on the general framework of time and frequency domain, parametric and non-parametric methods, input-output or output only techniques. Cutting edge tools are introduced including, nonlinear system identification methods; Bayesian tools; and advanced modal identification techniques (such as the Kalman and particle filters, the fast Bayesian FFT method). Advanced computational tools for uncertainty quantification are discussed to provide a link between monitoring and structural integrity assessment. In addition, full scale applications and field deployments that illustrate the workings and effectiveness of the introduced monitoring schemes are demonstrated.

  19. The health terminology project glossaries` structure

    Directory of Open Access Journals (Sweden)

    Sátia Marini

    2014-04-01

    Full Text Available Current paper was motivated by a Master´s degree in Translation Studies on one of the glossaries of the Health Terminology Project (PTS of the Ministry of Health (MS inBrazil, by which the products developed by the project were analyzed. The authors would like to forward their experience earned from the development of these instruments and from the evolution of the glossary´s layout and structure. Although within the same institution, each instrument is made suitable to the specific purpose of each area and the terminology project accumulates experience by the constant improvement of previously developed glossaries (adding new terms; providing the equivalent word in other languages for terms already defined and by the establishment of new ones. The evolution of the structure of the glossaries was qualitatively analyzed; remarks on the types of cross references were made; a quantitative survey of their main features was undertaken. Finally, the importance of this type of work should be underscored either within the government, or in the academy or in private companies, for the sharing of intellectual knowledge.

  20. Ionizing radiations in Italian health care structures

    International Nuclear Information System (INIS)

    Fizzano, M.R.; Frusteri, L.

    2006-01-01

    The Council of the European Union has completely renewed the framework regarding radiation protection by adopting some directives: Directive 97/43 EURATOM lays down the general principles of the radiation protection of individuals undergoing exposure to ionising radiations related to medical exposures, as a supplement of Directive 96/29 EURATOM laying down the basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionising radiations.The incorporation into Italian legislation of the European Community directives on the improvement of health and safety at work has promoted a vast effort in order to revise the surveillance approach in many facilities, including hospitals. In Italy, safety law is referred to every workplace; anyway the use of ionising radiations is ruled by specific laws. So in the health care structures it is necessary integrating both the laws and this process is often difficult to carry on. The Italian Legislative Decree 230/95, one the main laws that aim to protect workers against ionising radiations, introduced Directive 96/29/EURATOM. This Decree asks that a doctor and a technical expert analyse the workplace and classify area and workers in according to dose of ionising radiation established by law. The Italian Legislative Decree 626/94 asks that risk analysis in general is made by doctor and specialist in risk. So, in case of risk from ionising radiation, all these figures have to cooperate in order to make an evaluation risk document. (N.C.)

  1. Ionizing radiations in Italian health care structures

    Energy Technology Data Exchange (ETDEWEB)

    Fizzano, M.R.; Frusteri, L. [Technical Advisory Dept. for Risk Assessment and Prevention, Italian Workers Compensation Authority, Rome (Italy)

    2006-07-01

    The Council of the European Union has completely renewed the framework regarding radiation protection by adopting some directives: Directive 97/43 EURATOM lays down the general principles of the radiation protection of individuals undergoing exposure to ionising radiations related to medical exposures, as a supplement of Directive 96/29 EURATOM laying down the basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionising radiations.The incorporation into Italian legislation of the European Community directives on the improvement of health and safety at work has promoted a vast effort in order to revise the surveillance approach in many facilities, including hospitals. In Italy, safety law is referred to every workplace; anyway the use of ionising radiations is ruled by specific laws. So in the health care structures it is necessary integrating both the laws and this process is often difficult to carry on. The Italian Legislative Decree 230/95, one the main laws that aim to protect workers against ionising radiations, introduced Directive 96/29/EURATOM. This Decree asks that a doctor and a technical expert analyse the workplace and classify area and workers in according to dose of ionising radiation established by law. The Italian Legislative Decree 626/94 asks that risk analysis in general is made by doctor and specialist in risk. So, in case of risk from ionising radiation, all these figures have to cooperate in order to make an evaluation risk document. (N.C.)

  2. Structure health assessment and warning system (SHAWS)

    Science.gov (United States)

    Bock, Daniel M.; Kim, Keehoon; Mapar, Jalal

    2008-03-01

    We are developing a Structure Health Assessment and Warning System (SHAWS) based on building displacement measurements and wireless communication. SHAWS will measure and predict the stability/instability of a building, determine whether it is safe for emergency responders to enter during an emergency, and provide individual warnings on the condition of the structure. SHAWS incorporates remote sensing nodes (RSNs) installed on the exterior frame of a building. Each RSN includes a temperature sensor, a three-axis accelerometer making static-acceleration measurements, and a ZigBee wireless system (IEEE 802.15.4). The RSNs will be deployed remotely using an air cannon delivery system, with each RSN having an innovative adhesive structure for fast (<10 min) and strong installation under emergency conditions. Once the building has moved past a threshold (~0.25 in./building story), a warning will be issued to emergency responders. In addition to the RSNs, SHAWS will include a base station located on an emergency responder's primary vehicle, a PDA for mobile data display to guide responders, and individual warning modules that can be worn by each responder. The individual warning modules will include visual and audio indicators with a ZigBee receiver to provide the proper degree of warning to each responder.

  3. Towards "Zero" False Positive in Structural Health Monitoring

    National Research Council Canada - National Science Library

    Chiu, Wing K; Chang, F. K; Tian, Daniel T

    2007-01-01

    Structural Health Monitoring (SHM) is one aspect of a revolution based on the use of Smart Materials and Structures technologies that have the potential to provide major gains in structural performance and cost-efficient life management...

  4. Structural health monitoring system/method using electroactive polymer fibers

    Science.gov (United States)

    Scott-Carnell, Lisa A. (Inventor); Siochi, Emilie J. (Inventor)

    2013-01-01

    A method for monitoring the structural health of a structure of interest by coupling one or more electroactive polymer fibers to the structure and monitoring the electroactive responses of the polymer fiber(s). Load changes that are experienced by the structure cause changes in the baseline responses of the polymer fiber(s). A system for monitoring the structural health of the structure is also provided.

  5. FOREWORD: Structural Health Monitoring and Intelligent Infrastructure

    Science.gov (United States)

    Wu, Zhishen; Fujino, Yozo

    2005-06-01

    This special issue collects together 19 papers that were originally presented at the First International Conference on Structural Health Monitoring and Intelligent Infrastructure (SHMII-1'2003), held in Tokyo, Japan, on 13-15 November 2003. This conference was organized by the Japan Society of Civil Engineers (JSCE) with partial financial support from the Japan Society for the Promotion of Science (JSPS) and the Ministry of Education, Culture, Sport, Science and Technology, Japan. Many related organizations supported the conference. A total of 16 keynote papers including six state-of-the-art reports from different counties, six invited papers and 154 contributed papers were presented at the conference. The conference was attended by a diverse group of about 300 people from a variety of disciplines in academia, industry and government from all over the world. Structural health monitoring (SHM) and intelligent materials, structures and systems have been the subject of intense research and development in the last two decades and, in recent years, an increasing range of applications in infrastructure have been discovered both for existing structures and for new constructions. SHMII-1'2003 addressed progress in the development of building, transportation, marine, underground and energy-generating structures, and other civilian infrastructures that are periodically, continuously and/or actively monitored where there is a need to optimize their performance. In order to focus the current needs on SHM and intelligent technologies, the conference theme was set as 'Structures/Infrastructures Sustainability'. We are pleased to have the privilege to edit this special issue on SHM and intelligent infrastructure based on SHMII-1'2003. We invited some of the presenters to submit a revised/extended version of their paper that was included in the SHMII-1'2003 proceedings for possible publication in the special issue. Each paper included in this special issue was edited with the same

  6. Semi-supervised vibration-based classification and condition monitoring of compressors

    Science.gov (United States)

    Potočnik, Primož; Govekar, Edvard

    2017-09-01

    Semi-supervised vibration-based classification and condition monitoring of the reciprocating compressors installed in refrigeration appliances is proposed in this paper. The method addresses the problem of industrial condition monitoring where prior class definitions are often not available or difficult to obtain from local experts. The proposed method combines feature extraction, principal component analysis, and statistical analysis for the extraction of initial class representatives, and compares the capability of various classification methods, including discriminant analysis (DA), neural networks (NN), support vector machines (SVM), and extreme learning machines (ELM). The use of the method is demonstrated on a case study which was based on industrially acquired vibration measurements of reciprocating compressors during the production of refrigeration appliances. The paper presents a comparative qualitative analysis of the applied classifiers, confirming the good performance of several nonlinear classifiers. If the model parameters are properly selected, then very good classification performance can be obtained from NN trained by Bayesian regularization, SVM and ELM classifiers. The method can be effectively applied for the industrial condition monitoring of compressors.

  7. A Self-Powered Hybrid Energy Scavenging System Utilizing RF and Vibration Based Electromagnetic Harvesters

    International Nuclear Information System (INIS)

    Uluşan, H; Gharehbaghi, K; Külah, H; Zorlu, Ö; Muhtaroğlu, A

    2015-01-01

    This study presents a novel hybrid system that combines the power generated simultaneously by a vibration-based Electromagnetic (EM) harvester and a UHF band RF harvester. The novel hybrid scavenger interface uses a power management circuit in 180 nm CMOS technology to step-up and to regulate the combined output. At the first stage of the system, the RF harvester generates positive DC output with a 7-stage threshold compensated rectifier, while the EM harvester generates negative DC output with a self-powered AC/DC negative doubler circuit. At the second stage, the generated voltages are serially added, stepped-up with an on-chip charge pump circuit, and regulated to a typical battery voltage of 3 V. Test results indicate that the hybrid operation enables generation of 9 μW at 3 V output for a wide range of input stimulations, which could not be attained with either harvesting mode by itself. Moreover the hybrid system behaves as a typical battery, and keeps the output voltage stable at 3 V up to 18 μW of output power. The presented system is the first battery-like harvester to our knowledge that generates energy from two independent sources and regulates the output to a stable DC voltage. (paper)

  8. Experimental Aspects in the Vibration-Based Condition Monitoring of Large Hydrogenerators

    Directory of Open Access Journals (Sweden)

    Geraldo Carvalho Brito Junior

    2017-01-01

    Full Text Available Based on experimental observations on a set of twenty 700 MW hydrogenerators, compiled from several technical reports issued over the last three decades and collected from the reprocessing of the vibration signals recorded during the last commissioning tests, this paper shows that the accurate determination of the journal bearings operating conditions may be a difficult task. It shows that the outsize bearing brackets of large hydrogenerators are subject to substantial dimensional changes caused by external agents, like the generator electromagnetic field and the bearing cooling water temperature. It also shows that the shaft eccentricity of a journal bearing of a healthy large hydrogenerator, operating in steady-state condition, may experience unpredictable, sudden, and significant changes without apparent reasons. Some of these phenomena are reproduced in ordinary commissioning tests or may be noticed even during normal operation, while others are rarely observed or are only detected through special tests. These phenomena modify journal bearings stiffness and damping, changing the hydrogenerator dynamics, creating discrepancies between theoretical predictions and experimental measurements, and making damage detection and diagnostics difficult. Therefore, these phenomena must be analyzed and considered in the application of vibration-based condition monitoring to these rotating machines.

  9. A sequential model for the structure of health care utilization.

    NARCIS (Netherlands)

    Herrmann, W.J.; Haarmann, A.; Baerheim, A.

    2017-01-01

    Traditional measurement models of health care utilization are not able to represent the complex structure of health care utilization. In this qualitative study, we, therefore, developed a new model to represent the health care utilization structure. In Norway and Germany, we conducted episodic

  10. Wireless sensor networks for structural health monitoring

    CERN Document Server

    Cao, Jiannong

    2016-01-01

    This brief covers the emerging area of wireless sensor network (WSN)-based structural health monitoring (SHM) systems, and introduces the authors’ WSN-based platform called SenetSHM. It helps the reader differentiate specific requirements of SHM applications from other traditional WSN applications, and demonstrates how these requirements are addressed by using a series of systematic approaches. The brief serves as a practical guide, explaining both the state-of-the-art technologies in domain-specific applications of WSNs, as well as the methodologies used to address the specific requirements for a WSN application. In particular, the brief offers instruction for problem formulation and problem solving based on the authors’ own experiences implementing SenetSHM. Seven concise chapters cover the development of hardware and software design of SenetSHM, as well as in-field experiments conducted while testing the platform. The brief’s exploration of the SenetSHM platform is a valuable feature for civil engine...

  11. Packaging of structural health monitoring components

    Science.gov (United States)

    Kessler, Seth S.; Spearing, S. Mark; Shi, Yong; Dunn, Christopher T.

    2004-07-01

    Structural Health Monitoring (SHM) technologies have the potential to realize economic benefits in a broad range of commercial and defense markets. Previous research conducted by Metis Design and MIT has demonstrated the ability of Lamb waves methods to provide reliable information regarding the presence, location and type of damage in composite specimens. The present NSF funded program was aimed to study manufacturing, packaging and interface concepts for critical SHM components. The intention is to be able to cheaply manufacture robust actuating/sensing devices, and isolate them from harsh operating environments including natural, mechanical, or electrical extremes. Currently the issues related to SHM system durability have remained undressed. During the course of this research several sets of test devices were fabricated and packaged to protect the piezoelectric component assemblies for robust operation. These assemblies were then tested in hot and wet conditions, as well as in electrically noisy environments. Future work will aim to package the other supporting components such as the battery and wireless chip, as well as integrating all of these components together for operation. SHM technology will enable the reduction or complete elimination of scheduled inspections, and will allow condition-based maintenance for increased reliability and reduced overall life-cycle costs.

  12. An autonomous structural health monitoring solution

    Science.gov (United States)

    Featherston, Carol A.; Holford, Karen M.; Pullin, Rhys; Lees, Jonathan; Eaton, Mark; Pearson, Matthew

    2013-05-01

    Combining advanced sensor technologies, with optimised data acquisition and diagnostic and prognostic capability, structural health monitoring (SHM) systems provide real-time assessment of the integrity of bridges, buildings, aircraft, wind turbines, oil pipelines and ships, leading to improved safety and reliability and reduced inspection and maintenance costs. The implementation of power harvesting, using energy scavenged from ambient sources such as thermal gradients and sources of vibration in conjunction with wireless transmission enables truly autonomous systems, reducing the need for batteries and associated maintenance in often inaccessible locations, alongside bulky and expensive wiring looms. The design and implementation of such a system however presents numerous challenges. A suitable energy source or multiple sources capable of meeting the power requirements of the system, over the entire monitoring period, in a location close to the sensor must be identified. Efficient power management techniques must be used to condition the power and deliver it, as required, to enable appropriate measurements to be taken. Energy storage may be necessary, to match a continuously changing supply and demand for a range of different monitoring states including sleep, record and transmit. An appropriate monitoring technique, capable of detecting, locating and characterising damage and delivering reliable information, whilst minimising power consumption, must be selected. Finally a wireless protocol capable of transmitting the levels of information generated at the rate needed in the required operating environment must be chosen. This paper considers solutions to some of these challenges, and in particular examines SHM in the context of the aircraft environment.

  13. Structural Health Monitoring: Numerical Damage Predictor for Composite Structures

    National Research Council Canada - National Science Library

    Lannamann, Daniel

    2001-01-01

    .... Wide use of composites is found in aircraft, armored vehicles, ships and civil structures This present research demonstrates the ability to numerically detect damage in a composite sandwich structure...

  14. Organizational Structure and Management in Romanian Health System

    OpenAIRE

    Boldureanu Daniel; Boldureanu Gabriela

    2010-01-01

    The health system in Romania in a continuous transformation from a centralized system (type Semashko) exists before 1989 year to one based on social health insurance (type Bismark). This paper examines the management and the organizational structure of the health system in Romania, and the relations between them in the context of the Health Reform Law.

  15. A Vibration-Based MEMS Piezoelectric Energy Harvester and Power Conditioning Circuit

    Directory of Open Access Journals (Sweden)

    Hua Yu

    2014-02-01

    Full Text Available This paper presents a micro-electro-mechanical system (MEMS piezoelectric power generator array for vibration energy harvesting. A complete design flow of the vibration-based energy harvester using the finite element method (FEM is proposed. The modal analysis is selected to calculate the resonant frequency of the harvester, and harmonic analysis is performed to investigate the influence of the geometric parameters on the output voltage. Based on simulation results, a MEMS Pb(Zr,TiO3 (PZT cantilever array with an integrated large Si proof mass is designed and fabricated to improve output voltage and power. Test results show that the fabricated generator, with five cantilever beams (with unit dimensions of about 3 × 2.4 × 0.05 mm3 and an individual integrated Si mass dimension of about 8 × 12.4 × 0.5 mm3, produces a output power of 66.75 μW, or a power density of 5.19 μW∙mm−3∙g−2 with an optimal resistive load of 220 kΩ from 5 m/s2 vibration acceleration at its resonant frequency of 234.5 Hz. In view of high internal impedance characteristic of the PZT generator, an efficient autonomous power conditioning circuit, with the function of impedance matching, energy storage and voltage regulation, is then presented, finding that the efficiency of the energy storage is greatly improved and up to 64.95%. The proposed self-supplied energy generator with power conditioning circuit could provide a very promising complete power supply solution for wireless sensor node loads.

  16. A vibration-based MEMS piezoelectric energy harvester and power conditioning circuit.

    Science.gov (United States)

    Yu, Hua; Zhou, Jielin; Deng, Licheng; Wen, Zhiyu

    2014-02-19

    This paper presents a micro-electro-mechanical system (MEMS) piezoelectric power generator array for vibration energy harvesting. A complete design flow of the vibration-based energy harvester using the finite element method (FEM) is proposed. The modal analysis is selected to calculate the resonant frequency of the harvester, and harmonic analysis is performed to investigate the influence of the geometric parameters on the output voltage. Based on simulation results, a MEMS Pb(Zr,Ti)O3 (PZT) cantilever array with an integrated large Si proof mass is designed and fabricated to improve output voltage and power. Test results show that the fabricated generator, with five cantilever beams (with unit dimensions of about 3 × 2.4 × 0.05 mm3) and an individual integrated Si mass dimension of about 8 × 12.4 × 0.5 mm3, produces a output power of 66.75 μW, or a power density of 5.19 μW∙mm-3∙g-2 with an optimal resistive load of 220 kΩ from 5 m/s2 vibration acceleration at its resonant frequency of 234.5 Hz. In view of high internal impedance characteristic of the PZT generator, an efficient autonomous power conditioning circuit, with the function of impedance matching, energy storage and voltage regulation, is then presented, finding that the efficiency of the energy storage is greatly improved and up to 64.95%. The proposed self-supplied energy generator with power conditioning circuit could provide a very promising complete power supply solution for wireless sensor node loads.

  17. Dynamic Analysis with Fibre Optic Sensors for Structural Health Monitoring

    National Research Council Canada - National Science Library

    Paolozzi, Antonio; Gasbarri, Paolo

    2006-01-01

    Structural Health Monitoring (SHM) is a new frontier of non destructing testing. Often SHM is associated with fibre optic sensors whose signals can be used to identify the structure and consequently its damage...

  18. Vibration-based fixation assessment of tibial knee implants: A combined in vitro and in silico feasibility study.

    Science.gov (United States)

    Leuridan, Steven; Goossens, Quentin; Vander Sloten, Tom; De Landsheer, Koen; Delport, Hendrik; Pastrav, Leonard; Denis, Kathleen; Desmet, Wim; Vander Sloten, Jos

    2017-11-01

    The preoperative diagnosis of loosening of cemented tibial knee implants is challenging. This feasibility study explored the basic potential of a vibration-based method as an alternative diagnostic technique to assess the fixation state of a cemented tibia implant and establish the method's sensitivity limits. A combined in vitro and in silico approach was pursued. Several loosening cases were simulated. The largest changes in the vibrational behavior were obtained in the frequency range above 1500 Hz. The vibrational behavior was described with two features; the frequency response function and the power spectral density band power. Using both features, all experimentally simulated loosening cases could clearly be distinguished from the fully cemented cases. By complementing the experimental work with an in silico study, it was shown that loosening of approximately 14% of the implant surface on the lateral and medial side was detectable with a vibration-based method. Proximal lateral and medial locations on the tibia or locations toward the edge of the implant surface measured in the longitudinal direction were the most sensitive measurement and excitation locations to assess implant fixation. These results contribute to the development of vibration-based methods as an alternative follow-up method to detect loosened tibia implants. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  19. Structural health monitoring with a wireless vibration sensor network

    NARCIS (Netherlands)

    Basten, T.G.H.; Sas, P; Schiphorst, F.B.A.; Jonckheere, S.; Moens, D.

    2012-01-01

    Advanced maintenance strategies for infrastructure assets such as bridges or off shore wind turbines require actual and reliable information of the maintenance status. Structural health monitoring based on vibration sensing can help in supplying the input needed for structural health monitoring

  20. System identification and structural health monitoring of bridge structures

    OpenAIRE

    Islami, Kleidi

    2013-01-01

    This research study addresses two issues for the identification of structural characteristics of civil infrastructure systems. The first one is related to the problem of dynamic system identification, by means of experimental and operational modal analysis, applied to a large variety of bridge structures. Based on time and frequency domain techniques and mainly with output-only acceleration, velocity or strain data, modal parameters have been estimated for suspension bridges, masonry arch bri...

  1. Health lifestyle theory and the convergence of agency and structure.

    Science.gov (United States)

    Cockerham, William C

    2005-03-01

    This article utilizes the agency-structure debate as a framework for constructing a health lifestyle theory. No such theory currently exists, yet the need for one is underscored by the fact that many daily lifestyle practices involve considerations of health outcomes. An individualist paradigm has influenced concepts of health lifestyles in several disciplines, but this approach neglects the structural dimensions of such lifestyles and has limited applicability to the empirical world. The direction of this article is to present a theory of health lifestyles that includes considerations of both agency and structure, with an emphasis upon restoring structure to its appropriate position. The article begins by defining agency and structure, followed by presentation of a health lifestyle model and the theoretical and empirical studies that support it.

  2. Structural health and the politics of African American masculinity.

    Science.gov (United States)

    Metzl, Jonathan M

    2013-07-01

    This commentary describes ways in which notions of African American men's "health" attained by individual choice-embedded in the notion that African American men should visit doctors or engage in fewer risky behaviors-are at times in tension with larger cultural, economic, and political notions of "health." It argues that efforts to improve the health of Black men must take structural factors into account, and failure to do so circumvents even well-intentioned efforts to improve health outcomes. Using historical examples, the article shows how attempts to identify and intervene into what are now called social determinants of health are strengthened by addressing on-the-ground diagnostic disparities and also the structural violence and racism embedded within definitions of illness and health. And, that, as such, we need to monitor structural barriers to health that exist in institutions ostensibly set up to incarcerate or contain Black men and in institutions ostensibly set up to help them.

  3. Integrated Structural Health Management, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) proposes to advance the state of the art in composite health management through refinement of an existing technology developed...

  4. Development of structural health monitoring techniques using dynamics testing

    Energy Technology Data Exchange (ETDEWEB)

    James, G.H. III [Sandia National Labs., Albuquerque, NM (United States). Experimental Structural Dynamics Dept.

    1996-03-01

    Today`s society depends upon many structures (such as aircraft, bridges, wind turbines, offshore platforms, buildings, and nuclear weapons) which are nearing the end of their design lifetime. Since these structures cannot be economically replaced, techniques for structural health monitoring must be developed and implemented. Modal and structural dynamics measurements hold promise for the global non-destructive inspection of a variety of structures since surface measurements of a vibrating structure can provide information about the health of the internal members without costly (or impossible) dismantling of the structure. In order to develop structural health monitoring for application to operational structures, developments in four areas have been undertaken within this project: operational evaluation, diagnostic measurements, information condensation, and damage identification. The developments in each of these four aspects of structural health monitoring have been exercised on a broad range of experimental data. This experimental data has been extracted from structures from several application areas which include aging aircraft, wind energy, aging bridges, offshore structures, structural supports, and mechanical parts. As a result of these advances, Sandia National Laboratories is in a position to perform further advanced development, operational implementation, and technical consulting for a broad class of the nation`s aging infrastructure problems.

  5. Intelligent Structural Health Management of Civil Infrastructure

    Science.gov (United States)

    2012-10-19

    The collapse of the I-35W Mississippi River Bridge in Minneapolis has spawned a growing interest in the : development of reliable techniques for evaluating the structural integrity of civil infrastructure. Current inspection : techniques tailored to ...

  6. Structural health monitoring of grandstands: a review

    Directory of Open Access Journals (Sweden)

    Gómez-Casero Fuentes Miguel Ángel

    2015-01-01

    Full Text Available This article is a state of the art about Grandstands. The Grandstands are slender structures designed to accommodate a large number of people, which are specially under the actions of wind and the human-structure interaction. Over the years, it has been discuss of this topic, although still the number of publications still remain low. The human-structure interaction is a complex issue, where the loads may have different behaviours, depending many factors, including: type of audience (active or passive, public behaviour (jumping, walking, running, clapping, vandal loads, type of event (sports, concerts, meeting, position and posture of the individual, even influences the type of seat (with or without back, stiffness. However, the structure will behave differently when empty or fully occupied. Another load to consider is the wind, especially when the structure has a roof, screens, large-scale advertising, etc. These two types of loads can interact together, which implies an increase in the normal number of load combinations to consider. There are biomechanical models of human behaviour, used for design these types of structures. In addition, there are mathematical models to simulate the behaviour of the Grandstands by numerical methods. In recent years, all these models are throwing good results, against laboratory tests performed. It has also been monitored real Grandstands. This paper compiles all existing information on this topic.

  7. Sensor distributions for structural monitoring

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Bernal, Dionisio

    2017-01-01

    Deciding on the spatial distribution of output sensors for vibration-based structural health monitoring (SHM) is a task that has been, and still is, studied extensively. Yet, when referring to the conventional damage characterization hierarchy, composed of detection, localization, and quantificat......Deciding on the spatial distribution of output sensors for vibration-based structural health monitoring (SHM) is a task that has been, and still is, studied extensively. Yet, when referring to the conventional damage characterization hierarchy, composed of detection, localization......, and quantification, it is primarily the first component that has been addressed with regard to optimal sensor placement. In this particular context, a common approach is to distribute sensors, of which the amount is determined a priori, such that some scalar function of the probability of detection for a pre......-defined set of damage patterns is maximized. Obviously, the optimal sensor distribution, in terms of damage detection, is algorithm-dependent, but studies have showed how correlation generally exists between the different strategies. However, it still remains a question how this “optimality” correlates...

  8. Smart Materials in Structural Health Monitoring, Control and Biomechanics

    CERN Document Server

    Soh, Chee-Kiong; Bhalla, Suresh

    2012-01-01

    "Smart Materials in Structural Health Monitoring, Control and Biomechanics" presents the latest developments in structural health monitoring, vibration control and biomechanics using smart materials. The book mainly focuses on piezoelectric, fibre optic and ionic polymer metal composite materials. It introduces concepts from the very basics and leads to advanced modelling (analytical/ numerical), practical aspects (including software/ hardware issues) and case studies spanning civil, mechanical and aerospace structures, including bridges, rocks and underground structures. This book is intended for practicing engineers, researchers from academic and R&D institutions and postgraduate students in the fields of smart materials and structures, structural health monitoring, vibration control and biomedical engineering. Professor Chee-Kiong Soh and Associate Professor Yaowen Yang both work at the School of Civil and Environmental Engineering, Nanyang Technological University, Singapore. Dr. Suresh Bhalla is an A...

  9. Financing reform and structural change in the health services industry.

    Science.gov (United States)

    Higgins, C W; Phillips, B U

    1986-08-01

    This paper reviews the major trends in financing reform, emphasizing their impact on those characteristics of the market for health services that economists have viewed as monopolistic, and discusses the implications of structural change for the allied health professions. Hopefully, by understanding the fundamental forces of change and responding to uncertainty with flexibility and imagination, the allied health professions can capitalize on the opportunities afforded by structural change. Overall, these trends should result in the long-term outlook for use of allied health services to increase at an average annual rate of 9% to 10%. Allied health professionals may also witness an increase in independent practice opportunities. Finally, redistribution of jobs will likely occur in favor of outpatient facilities, home health agencies, and nontraditional settings. This in turn will have an impact on allied health education, which will need to adapt to these types of reforms.

  10. Implementing a structured triage system at a community health ...

    African Journals Online (AJOL)

    Implementing a structured triage system at a community health centre using Kaizen. ... and a resultant increased workload for doctors; management is concerned ... Aim: We set out to standardise the triage process and to manage unbooked ...

  11. Multidisciplinary health monitoring of a steel bridge deck structure

    NARCIS (Netherlands)

    Pahlavan, P.L.; Pijpers, R.J.M.; Paulissen, J.H.; Hakkesteegt, H.C.; Jansen, T.H.

    2013-01-01

    Fatigue cracks in orthotropic bridge decks are an important cause for the necessary renovation of existing bridges. Parallel utilization of various technologies based on different physical sensing principles can potentially maximize the efficiency of structural health monitoring (SHM) systems for

  12. Structure, health benefits, antioxidant property and processing and ...

    African Journals Online (AJOL)

    Structure, health benefits, antioxidant property and processing and storage of carotenoids. ... It is sensitive to heat, light and oxygen. Enzymatic ... Thermal treatment and freezing increases the extractability of b-carotene from the food matrices.

  13. Quantifiable and Reliable Structural Health Management Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Major concerns for implementing a practical built-in structural health monitoring system are prediction accuracy and data reliability. It is proposed to develop...

  14. Prognostics Design Solutions in Structural Health Monitoring Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The chapter describes the application of prognostic techniques to the domain of structural health and demonstrates the efficacy of the methods using fatigue data...

  15. On the value of structural health monitoring

    DEFF Research Database (Denmark)

    Faber, Michael Havbro; Thöns, Sebastian

    2014-01-01

    in the fields of SHM and the quantification of value of information as well as the identification of typical situations in structural engineering in which SHM has the potential to provide value beyond its costs. Subsequently, the theoretical framework which allows for the quantification of the value...... of information collected through SHM systems is developed and elaborated. It is shown how the value of information can be quantified to support the assessment and optimization of decisions on whether and how to implement SHM. To illustrate the use of the developed theoretical framework for evaluating the benefit...

  16. Can market structure explain cross-country differences in health?

    Directory of Open Access Journals (Sweden)

    Kate Rybczynski

    2013-03-01

    Full Text Available There is a well documented health disparity between several European countries and the United States. This health gap remains even after controlling for socioeconomic status and risk factors. At the same time, we note that the U.S. market structure is characterized by significantly more large corporations and "super-sized" retail outlets than Europe. Because big business is hierarchical in nature and has been reported to engender urban sprawl, inferior work environments, and loss of social capital, all identified as correlates of poor health, we suggest that differences in market structure may help account for some of the unexplained differences in health across Europe and North America. Using national level data, this study explores the relationship between market structure and health. We investigate whether individuals who live in countries with proportionately more small business are healthier than those who do not. We use two measures of national health: life expectancy at birth, and age-standardized estimates of diabetes rates. Results from ordinary least squares regressions suggest that, there is a large and statistically significant association between market structure (the ratio of small to total businesses and health, even after controlling income, public percent of health expenditure, and obesity rates. This association is robust to additional controls such as insufficient physical activity, smoking, alcohol disease, and air pollution.

  17. Time-frequency Methods for Structural Health Monitoring

    NARCIS (Netherlands)

    Pyayt, A.L.; Kozionov, A.P.; Mokhov, I.I.; Lang, B.; Meijer, R.J.; Krzhizhanovskaya, V.V.; Sloot, P.M.A.

    2014-01-01

    Detection of early warning signals for the imminent failure of large and complex engineered structures is a daunting challenge with many open research questions. In this paper we report on novel ways to perform Structural Health Monitoring (SHM) of flood protection systems (levees, earthen dikes and

  18. Time-frequency methods for structural health monitoring

    NARCIS (Netherlands)

    Pyayt, A.L.; Kozionov, A.P.; Mokhov, I.I.; Lang, B.; Meijer, R.J.; Krzhizhanovskaya, V.V.; Sloot, P.M.A.

    2014-01-01

    Detection of early warning signals for the imminent failure of large and complex engineered structures is a daunting challenge with many open research questions. In this paper we report on novel ways to perform Structural Health Monitoring (SHM) of flood protection systems (levees, earthen dikes and

  19. Technical Specifications of Structural Health Monitoring for Highway Bridges: New Chinese Structural Health Monitoring Code

    Directory of Open Access Journals (Sweden)

    Fernando Moreu

    2018-03-01

    Full Text Available Governments and professional groups related to civil engineering write and publish standards and codes to protect the safety of critical infrastructure. In recent decades, countries have developed codes and standards for structural health monitoring (SHM. During this same period, rapid growth in the Chinese economy has led to massive development of civil engineering infrastructure design and construction projects. In 2016, the Ministry of Transportation of the People’s Republic of China published a new design code for SHM systems for large highway bridges. This document is the first technical SHM code by a national government that enforces sensor installation on highway bridges. This paper summarizes the existing international technical SHM codes for various countries and compares them with the new SHM code required by the Chinese Ministry of Transportation. This paper outlines the contents of the new Chinese SHM code and explains its relevance for the safety and management of large bridges in China, introducing key definitions of the Chinese–United States SHM vocabulary and their technical significance. Finally, this paper discusses the implications for the design and implementation of a future SHM codes, with suggestions for similar efforts in United States and other countries.

  20. More than culture: structural racism, intersectionality theory, and immigrant health.

    Science.gov (United States)

    Viruell-Fuentes, Edna A; Miranda, Patricia Y; Abdulrahim, Sawsan

    2012-12-01

    Explanations for immigrant health outcomes often invoke culture through the use of the concept of acculturation. The over reliance on cultural explanations for immigrant health outcomes has been the topic of growing debate, with the critics' main concern being that such explanations obscure the impact of structural factors on immigrant health disparities. In this paper, we highlight the shortcomings of cultural explanations as currently employed in the health literature, and argue for a shift from individual culture-based frameworks, to perspectives that address how multiple dimensions of inequality intersect to impact health outcomes. Based on our review of the literature, we suggest specific lines of inquiry regarding immigrants' experiences with day-to-day discrimination, as well as on the roles that place and immigration policies play in shaping immigrant health outcomes. The paper concludes with suggestions for integrating intersectionality theory in future research on immigrant health. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Implications of network structure on public health collaboratives.

    Science.gov (United States)

    Retrum, Jessica H; Chapman, Carrie L; Varda, Danielle M

    2013-10-01

    Interorganizational collaboration is an essential function of public health agencies. These partnerships form social networks that involve diverse types of partners and varying levels of interaction. Such collaborations are widely accepted and encouraged, yet very little comparative research exists on how public health partnerships develop and evolve, specifically in terms of how subsequent network structures are linked to outcomes. A systems science approach, that is, one that considers the interdependencies and nested features of networks, provides the appropriate methods to examine the complex nature of these networks. Applying Mays and Scutchfields's categorization of "structural signatures" (breadth, density, and centralization), this research examines how network structure influences the outcomes of public health collaboratives. Secondary data from the Program to Analyze, Record, and Track Networks to Enhance Relationships (www.partnertool.net) data set are analyzed. This data set consists of dyadic (N = 12,355), organizational (N = 2,486), and whole network (N = 99) data from public health collaborations around the United States. Network data are used to calculate structural signatures and weighted least squares regression is used to examine how network structures can predict selected intermediary outcomes (resource contributions, overall value and trust rankings, and outcomes) in public health collaboratives. Our findings suggest that network structure may have an influence on collaborative-related outcomes. The structural signature that had the most significant relationship to outcomes was density, with higher density indicating more positive outcomes. Also significant was the finding that more breadth creates new challenges such as difficulty in reaching consensus and creating ties with other members. However, assumptions that these structural components lead to improved outcomes for public health collaboratives may be slightly premature. Implications of

  2. Health sociology from post-structuralism to the new materialisms.

    Science.gov (United States)

    Fox, Nick J

    2016-01-01

    The article reviews the impact of post-structuralism and postmodern social theory upon health sociology during the past 20 years. It then addresses the emergence of new materialist perspectives, which to an extent build upon insights of post-structuralist concerning power, but mark a turn away from a textual or linguistic focus to address the range of materialities that affect health, illness and health care. I conclude by assessing the impact of these movements for health sociology. © The Author(s) 2015.

  3. [Position of health at international relations. Part I. Structural dimensions of health].

    Science.gov (United States)

    Cianciara, Dorota; Wysocki, Mirosław J

    2011-01-01

    In the article, the health is perceived as complex, multidimensional concept and not as absence of disease. This is consistent with public health perspective, where public health is regarded as public as well as political activity. It aims to solve health and social problems, depends on analysis of phenomena, needs the negotiations and relies on making decision on feasible directions of changes--what, why, how, where, when and by whom should be done. Public health policy developed as a result of international relations, and UN family fora especially, is regarded as significant for creating of health position. The aim of this article was: (1) the analysis of selected concepts and definitions related to structural dimensions of health, used in UN international arrangements; (2) an attempt to explain the evolution of health structure notions at worldwide agenda. The UN main bodies, programmes and funds working on the health field are mentioned and voting rules in UN General Assembly and World Health Assembly are reminded. The following structural dimensions were considered: (a) well-being, (b) human rights, (c) everyday resource, health potential, (4) equity. All were explored in WHO Constitution, Universal Declaration of Human Rights, International Covenant on Economic, Social and Cultural Rights, Ottawa Charter for Health Promotion and numerous WHA and UN GA resolutions, decisions as well as other documents. Some remarkable differences in English and Polish language versions and meanings were pointed out. It was argued that present perception of structural dimension of health is strongly derived from the preamble of the WHO Constitution adopted and signed on 22 July 1946 by the representatives of 61 States. It is an evidence of the strength of this document and wisdom of its authors. The greater progress is associated. with concepts and notion of organizational dimensions of health perceived as action and processes leading to health. Long-term efforts to strengthen

  4. Self-learning health monitoring algorithm in composite structures

    Science.gov (United States)

    Grassia, Luigi; Iannone, Michele; Califano, America; D'Amore, Alberto

    2018-02-01

    The paper describes a system that it is able of monitoring the health state of a composite structure in real time. The hardware of the system consists of a wire of strain sensors connected to a control unit. The software of the system elaborates the strain data and in real time is able to detect the presence of an eventual damage of the structures monitored with the strain sensors. The algorithm requires as input only the strains of the monitored structured measured on real time, i.e. those strains coming from the deformations of the composite structure due to the working loads. The health monitoring system does not require any additional device to interrogate the structure as often used in the literature, instead it is based on a self-learning procedure. The strain data acquired when the structure is healthy are used to set up the correlations between the strain in different positions of structure by means of neural network. Once the correlations between the strains in different position have been set up, these correlations act as a fingerprint of the healthy structure. In case of damage the correlation between the strains in the position of the structure near the damage will change due to the change of the stiffness of the structure caused by the damage. The developed software is able to recognize the change of the transfer function between the strains and consequently is able to detect the damage.

  5. Marketing health care to employees: the structure of employee health care plan satisfaction.

    Science.gov (United States)

    Mascarenhas, O A

    1993-01-01

    Providing cost-contained comprehensive quality health care to maintain healthy and productive employees is a challenging problem for all employers. Using a representative panel of metropolitan employees, the author investigates the internal and external structure of employee satisfaction with company-sponsored health care plans. Employee satisfaction is differentiated into four meaningful groups of health care benefits, whereas its external structure is supported by the traditional satisfaction paradigms of expectation-disconfirmation, attribution, and equity. Despite negative disconfirmation, employees register sufficiently high health care satisfaction levels, which suggests some useful strategies that employers may consider implementing.

  6. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead, they grow up in single-parent households or in families with a step-parent. Hence, it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized both in the short and the long run by shocks in the family structure during childhood. I focus on educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1985 is used...... for the analysis. The empirical cross-sectional analysis indicates a negative relation between the number of family structure changes and children.s health, behavior, and educational outcomes. These results are con.rmed by a differences-in-differences analysis of health outcomes. This suggests...

  7. Investigation of the performances of PZT vs rare earth (BaLaTiO3) vibration based energy harvester

    Science.gov (United States)

    Pak, Nehemiah; Aris, Hasnizah; Nadia Taib, Bibi

    2017-11-01

    This study proposes the investigation of two piezoelectric material namely PZT and Lanthanum Doped Barium Titanate (BaLaTiO3) performance as a vibration based energy harvester. The piezoelectric material when applied mechanical stress or strain produces electricity through the piezoelectric effect. The vibration energy would exude mechanical energy and thus apply mechanical force on the energy harvester. The energy harvester would be designed and simulated using the piezoelectric material individually. The studied outputs are divided to frequency response, the load dependence, and the acceleration dependence whereby measurement are observed and taken at maximum power output. The simulation is done using the cantilevers design which employs d31 type of constants. Three different simulations to study the dependence of output power on the resonant frequency response, load and acceleration have found that material that exhibit highest power generation was the BaLaTiO3.

  8. Investigation of the performances of PZT vs rare earth (BaLaTiO3 vibration based energy harvester

    Directory of Open Access Journals (Sweden)

    Pak Nehemiah

    2017-01-01

    Full Text Available This study proposes the investigation of two piezoelectric material namely PZT and Lanthanum Doped Barium Titanate (BaLaTiO3 performance as a vibration based energy harvester. The piezoelectric material when applied mechanical stress or strain produces electricity through the piezoelectric effect. The vibration energy would exude mechanical energy and thus apply mechanical force on the energy harvester. The energy harvester would be designed and simulated using the piezoelectric material individually. The studied outputs are divided to frequency response, the load dependence, and the acceleration dependence whereby measurement are observed and taken at maximum power output. The simulation is done using the cantilevers design which employs d31 type of constants. Three different simulations to study the dependence of output power on the resonant frequency response, load and acceleration have found that material that exhibit highest power generation was the BaLaTiO3.

  9. Vibration Based Damage Assessment of a Cantilever using a Neural Network

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    In this paper the possibility of using a Multilayer Perceptron (MLP) network trained with with the Backpropagation Algorithm as a non-destructive damage assessment technique to locate and quantify a damage in structures is investigated.......In this paper the possibility of using a Multilayer Perceptron (MLP) network trained with with the Backpropagation Algorithm as a non-destructive damage assessment technique to locate and quantify a damage in structures is investigated....

  10. Applications of fiber optic sensors in concrete structural health monitoring

    Science.gov (United States)

    Dai, Jingyun; Zhang, Wentao; Sun, Baochen; Du, Yanliang

    2007-11-01

    The research of fiber optic extrinsic Fabry-Perot interferometer (EFPI) sensors and their applications in concrete structural health monitoring are presented in this paper. Different types of fiber optic EFPI sensors are designed and fabricated. Experiments are carried out to test the performance of the sensors. The results show that the sensors have good linearity and stability. The applications of the fiber optic EFPI sensors in concrete structural health monitoring are also introduced. Ten fiber optic sensors are embedded into one section of the Liaohe Bridge in Qinghuangdao-Shenyang Railway. Field test demonstrates that the results of fiber optic sensors agree well with conventional strain gauges.

  11. Structural health monitoring an advanced signal processing perspective

    CERN Document Server

    Chen, Xuefeng; Mukhopadhyay, Subhas

    2017-01-01

    This book highlights the latest advances and trends in advanced signal processing (such as wavelet theory, time-frequency analysis, empirical mode decomposition, compressive sensing and sparse representation, and stochastic resonance) for structural health monitoring (SHM). Its primary focus is on the utilization of advanced signal processing techniques to help monitor the health status of critical structures and machines encountered in our daily lives: wind turbines, gas turbines, machine tools, etc. As such, it offers a key reference guide for researchers, graduate students, and industry professionals who work in the field of SHM.

  12. Structural Health Monitoring Based on Combined Structural Global and Local Frequencies

    Directory of Open Access Journals (Sweden)

    Jilin Hou

    2014-01-01

    Full Text Available This paper presents a parameter estimation method for Structural Health Monitoring based on the combined measured structural global frequencies and structural local frequencies. First, the global test is experimented to obtain the low order modes which can reflect the global information of the structure. Secondly, the mass is added on the member of structure to increase the local dynamic characteristic and to make the member have local primary frequency, which belongs to structural local frequency and is sensitive to local parameters. Then the parameters of the structure can be optimized accurately using the combined structural global frequencies and structural local frequencies. The effectiveness and accuracy of the proposed method are verified by the experiment of a space truss.

  13. Health monitoring of civil structures using fiber optic sensors

    International Nuclear Information System (INIS)

    Varma, Veto; Kumar, Praveen; Charan, J.J.; Reddy, G.R.; Vaze, K.K.; Kushwaha, H.S.

    2003-08-01

    During the lifetime of the reactor, the civil structure is subjected to many operational and environmental loads. Hence it is increasingly important to monitor the conditions of the structure and insure its safety and integrity. The conventional gauges have proved to be not sufficiently catering the problem of long term health monitoring of the structure because of its many limitations. Hence it is mandatory to develop a technique for the above purpose. Present study deals with the application of Fiber optic sensors (EFPI strain Gauges) in the civil structure for its health monitoring. Various experiments were undertaken and suitability of sensors was checked. A technique to embed the optical sensor inside the concrete is successfully developed and tested. (author)

  14. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead they grow up in single parent households or in families with a step-parent. Hence it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized both in the short and the long run by shocks in the family structure during childhood. I focus on educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1983, 1984, and 1985...... is used for the analysis. The empirical cross-sectional analysis indicates a negative relation between the number of family structure changes and children.s educational outcomes. Children experiencing many family structure changes also seem to have worse health outcomes....

  15. A Simple Demonstration of Concrete Structural Health Monitoring Framework

    Energy Technology Data Exchange (ETDEWEB)

    Mahadevan, Sankaran [Idaho National Lab. (INL), Idaho Falls, ID (United States); Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cai, Guowei [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nath, Paromita [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bao, Yanqing [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bru Brea, Jose Maria [Idaho National Lab. (INL), Idaho Falls, ID (United States); Koester, David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Adams, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kosson, David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    Assessment and management of aging concrete structures in nuclear power plants require a more systematic approach than simple reliance on existing code margins of safety. Structural health monitoring of concrete structures aims to understand the current health condition of a structure based on heterogeneous measurements to produce high confidence actionable information regarding structural integrity that supports operational and maintenance decisions. This ongoing research project is seeking to develop a probabilistic framework for health diagnosis and prognosis of aging concrete structures in a nuclear power plant subjected to physical, chemical, environment, and mechanical degradation. The proposed framework consists of four elements—damage modeling, monitoring, data analytics, and uncertainty quantification. This report describes a proof-of-concept example on a small concrete slab subjected to a freeze-thaw experiment that explores techniques in each of the four elements of the framework and their integration. An experimental set-up at Vanderbilt University’s Laboratory for Systems Integrity and Reliability is used to research effective combination of full-field techniques that include infrared thermography, digital image correlation, and ultrasonic measurement. The measured data are linked to the probabilistic framework: the thermography, digital image correlation data, and ultrasonic measurement data are used for Bayesian calibration of model parameters, for diagnosis of damage, and for prognosis of future damage. The proof-of-concept demonstration presented in this report highlights the significance of each element of the framework and their integration.

  16. Young smokers' narratives: public health, disadvantage and structural violence.

    Science.gov (United States)

    Lewis, Sue; Russell, Andrew

    2013-06-01

    This research article on youth smoking in disadvantaged communities is the product of a qualitative study to understand the issues faced by young smokers--and those trying not to be smokers--in such communities. Environmental factors and peer influence are widely recognised influences on adolescents' take-up and continuation of smoking but less is known about whether, what, how and why circumstances in disadvantaged communities affect young people's pathways towards and away from smoking. Focusing on a youth club in a disadvantaged neighbourhood in the North East of England, narratives about young people's relationships with tobacco provide an ethnographically rich, thick description of the experiences of a group that is too often easily ignored. We argue that young people are caught between competing domains that together exert a form of structural violence. These are, first, the economic and political structures that have overseen de-industrialisation; second, the media structures that create desire for what they cannot afford; third the structures of international organised crime that conspire to provide them with the means to consume from which 'legitimate' structures effectively exclude them. Rather than expecting young people to comply with the health imperative, interventions need to bridge issues of agency and critical consciousness, which structural violence otherwise insidiously erodes. © 2013 The Authors. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

  17. Minority group status and healthful aging: social structure still matters.

    Science.gov (United States)

    Angel, Jacqueline L; Angel, Ronald J

    2006-07-01

    During the last 4 decades, a rapid increase has occurred in the number of survey-based and epidemiological studies of the health profiles of adults in general and of the causes of disparities between majority and minority Americans in particular. According to these studies, healthful aging consists of the absence of disease, or at least of the most serious preventable diseases and their consequences, and findings consistently reveal serious African American and Hispanic disadvantages in terms of healthful aging. We (1) briefly review conceptual and operational definitions of race and Hispanic ethnicity, (2) summarize how ethnicity-based differentials in health are related to social structures, and (3) emphasize the importance of attention to the economic, political, and institutional factors that perpetuate poverty and undermine healthful aging among certain groups.

  18. Smart Sensing Technologies for Structural Health Monitoring of Civil Engineering Structures

    OpenAIRE

    M. Sun; W. J. Staszewski; R. N. Swamy

    2010-01-01

    Structural Health Monitoring (SHM) aims to develop automated systems for the continuous monitoring, inspection, and damage detection of structures with minimum labour involvement. The first step to set up a SHM system is to incorporate a level of structural sensing capability that is reliable and possesses long term stability. Smart sensing technologies including the applications of fibre optic sensors, piezoelectric sensors, magnetostrictive sensors and self-diagnosing fibre reinforced compo...

  19. Health Monitoring of Composite Material Structures using a Vibrometry Technique

    Science.gov (United States)

    Schulz, Mark J.

    1997-01-01

    Large composite material structures such as aircraft and Reusable Launch Vehicles (RLVS) operate in severe environments comprised of vehicle dynamic loads, aerodynamic loads, engine vibration, foreign object impact, lightning strikes, corrosion, and moisture absorption. These structures are susceptible to damage such as delamination, fiber breaking/pullout, matrix cracking, and hygrothermal strain. To ensure human safety and load-bearing integrity, these structures must be inspected to detect and locate often invisible damage and faults before becoming catastrophic. Moreover, nearly all future structures will need some type of in-service inspection technique to increase their useful life and reduce maintenance and overall costs. Possible techniques for monitoring the health and indicating damage on composite structures include: c-scan, thermography, acoustic emissions using piezoceramic actuators or fiber-optic wires with gratings, laser ultrasound, shearography, holography, x-ray, and others. These techniques have limitations in detecting damage that is beneath the surface of the structure, far away from a sensor location, or during operation of the vehicle. The objective of this project is to develop a more global method for damage detection that is based on structural dynamics principles, and can inspect for damage when the structure is subjected to vibratory loads to expose faults that may not be evident by static inspection. A Transmittance Function Monitoring (TFM) method is being developed in this project for ground-based inspection and operational health monitoring of large composite structures as a RLV. A comparison of the features of existing health monitoring approaches and the proposed TFM method is given.

  20. Simultaneous Structural Health Monitoring and Vibration Control of Adaptive Structures Using Smart Materials

    Directory of Open Access Journals (Sweden)

    Myung-Hyun Kim

    2002-01-01

    Full Text Available The integration of actuators and sensors using smart materials enabled various applications including health monitoring and structural vibration control. In this study, a robust control technique is designed and implemented in order to reduce vibration of an active structure. Special attention is given to eliminating the possibility of interaction between the health monitoring system and the control system. Exploiting the disturbance decoupling characteristic of the sliding mode observer, it is demonstrated that the proposed observer can eliminate the possible high frequency excitation from the health monitoring system. At the same time, a damage identification scheme, which tracks the changes of mechanical impedance due to the presence of damage, has been applied to assess the health condition of structures. The main objective of this paper is to examine the potential of combining the two emerging techniques together. Using the collocated piezoelectric sensors/actuators for vibration suppression as well as for health monitoring, this technique enabled to reduce the number of system components, while enhancing the performance of structures. As an initial study, both simulation and experimental investigations were performed for an active beam structure. The results show that this integrated technique can provide substantial vibration reductions, while detecting damage on the structure at the same time.

  1. Factor structure and psychometric properties of the General Health ...

    African Journals Online (AJOL)

    Purpose: There is little information about the reliability and validity of the 12-item General Health Questionnaire (GHQ-12) in Ghana. This study sought to examine the reliability and factor structure of the GHQ-12 in Ghanaian adolescents. Methods: High school students (N = 770) completed the GHQ-12 and the Adolescent ...

  2. System Identification of Wind Turbines for Structural Health Monitoring

    DEFF Research Database (Denmark)

    Perisic, Nevena

    Structural health monitoring is a multi-disciplinary engineering field that should allow the actual wind turbine maintenance programmes to evolve to the next level, hence increasing safety and reliability and decreasing turbines downtime. The main idea is to have a sensing system on the structure...... cases are considered, two practical problems from the wind industry are studied, i.e. monitoring of the gearbox shaft torque and the tower root bending moments. The second part of the thesis is focused on the influence of friction on the health of the wind turbine and on the nonlinear identification...... that monitors the system responses and notifies the operator when damages or degradations have been detected. However, some of the response signals that contain important information about the health of the wind turbine components cannot be directly measured, or measuring them is highly complex and costly...

  3. Managing mechanistic and organic structure in health care organizations.

    Science.gov (United States)

    Olden, Peter C

    2012-01-01

    Managers at all levels in a health care organization must organize work to achieve the organization's mission and goals. This requires managers to decide the organization structure, which involves dividing the work among jobs and departments and then coordinating them all toward the common purpose. Organization structure, which is reflected in an organization chart, may range on a continuum from very mechanistic to very organic. Managers must decide how mechanistic versus how organic to make the entire organization and each of its departments. To do this, managers should carefully consider 5 factors for the organization and for each individual department: external environment, goals, work production, size, and culture. Some factors may push toward more mechanistic structure, whereas others may push in the opposite direction toward more organic structure. Practical advice can help managers at all levels design appropriate structure for their departments and organization.

  4. Family structure and health, how companionship acts as a buffer against ill health

    Directory of Open Access Journals (Sweden)

    Kizuki Masashi

    2007-11-01

    Full Text Available Abstract Background Health and well-being are the result of synergistic interactions among a variety of determinants. Family structure and composition are social determinants that may also affect health behaviours and outcomes. This study was performed to examine the associations between family structure and health and to determine the protective effects of support mechanisms to improve quality of health outcome. Methods Six hundred people, selected by multistage sampling to obtain a representative population of men and women aged 20–60 living in communities in Japan, were included in this study. Data regarding subjective views of one's own health, family structure, lifestyle and social support were collected through structured face-to-face interviews on home visits. Systolic and diastolic blood pressures, height and weight were measured by trained examiners. The associations between family structure and health after controlling for demographics, lifestyle and social support were examined using logistic and linear regression analyses. Results Subjects living alone were significantly more likely to be in ill health, as determined using the General Health Questionnaire, in comparison to those in extended families (OR = 3.14. Subjects living alone or as couples were significantly more likely to suffer from severe hypertension in comparison to those living in extended families (OR = 8.25, OR = 4.90. These associations remained after controlling for the influence of lifestyle. Subjects living only with spouse or in nuclear family had higher probabilities of mental ill health in the absence than in the presence of people showing concern for their well-being. Conclusion The results of this study infers that a support mechanism consisting of companionship and the presence of family or other people concerned for one's well being acts as a buffer against deleterious influence of living in small family that will lead to improved quality of health outcome.

  5. Fibre Optic Sensors for Structural Health Monitoring of Aircraft Composite Structures: Recent Advances and Applications

    Science.gov (United States)

    Di Sante, Raffaella

    2015-01-01

    In-service structural health monitoring of composite aircraft structures plays a key role in the assessment of their performance and integrity. In recent years, Fibre Optic Sensors (FOS) have proved to be a potentially excellent technique for real-time in-situ monitoring of these structures due to their numerous advantages, such as immunity to electromagnetic interference, small size, light weight, durability, and high bandwidth, which allows a great number of sensors to operate in the same system, and the possibility to be integrated within the material. However, more effort is still needed to bring the technology to a fully mature readiness level. In this paper, recent research and applications in structural health monitoring of composite aircraft structures using FOS have been critically reviewed, considering both the multi-point and distributed sensing techniques. PMID:26263987

  6. Fibre Optic Sensors for Structural Health Monitoring of Aircraft Composite Structures: Recent Advances and Applications

    Directory of Open Access Journals (Sweden)

    Raffaella Di Sante

    2015-07-01

    Full Text Available In-service structural health monitoring of composite aircraft structures plays a key role in the assessment of their performance and integrity. In recent years, Fibre Optic Sensors (FOS have proved to be a potentially excellent technique for real-time in-situ monitoring of these structures due to their numerous advantages, such as immunity to electromagnetic interference, small size, light weight, durability, and high bandwidth, which allows a great number of sensors to operate in the same system, and the possibility to be integrated within the material. However, more effort is still needed to bring the technology to a fully mature readiness level. In this paper, recent research and applications in structural health monitoring of composite aircraft structures using FOS have been critically reviewed, considering both the multi-point and distributed sensing techniques.

  7. An approach for maximizing the smallest eigenfrequency of structure vibration based on piecewise constant level set method

    Science.gov (United States)

    Zhang, Zhengfang; Chen, Weifeng

    2018-05-01

    Maximization of the smallest eigenfrequency of the linearized elasticity system with area constraint is investigated. The elasticity system is extended into a large background domain, but the void is vacuum and not filled with ersatz material. The piecewise constant level set (PCLS) method is applied to present two regions, the original material region and the void region. A quadratic PCLS function is proposed to represent the characteristic function. Consequently, the functional derivative of the smallest eigenfrequency with respect to PCLS function takes nonzero value in the original material region and zero in the void region. A penalty gradient algorithm is proposed, which initializes the whole background domain with the original material and decreases the area of original material region till the area constraint is satisfied. 2D and 3D numerical examples are presented, illustrating the validity of the proposed algorithm.

  8. Changing structure to improve function: one academic health center's experience.

    Science.gov (United States)

    Alexander, B; Davis, L; Kohler, P O

    1997-04-01

    Academic health centers (AHCs) have been under siege for the past few years, with decreased federal and state funding for educational and research programs and increasing competition in the health care marketplace. In addition, many AHCs are burdened with the bureaucratic red tape of large educational institutions, which makes agility in responding to a demanding health care market difficult. The authors describe the response to these threats by Oregon Health Sciences University (OHSU), an approach that has been different from those of most similar institutions. OHSU chose to change its structure from being part of the state system of higher education to being an independent public corporation. The authors outline the political process of building widespread support for the legislation passed in 1995, the key features of the restructuring, the challenges faced before and after the transition to a public corporation, and lessons learned in this metamorphosis to a new form.

  9. Quantification of the Value of Structural Health Monitoring Information for Fatigue Deteriorating Structural Systems

    DEFF Research Database (Denmark)

    Thöns, Sebastian; Schneider, Ronald; Faber, Michael Havbro

    2015-01-01

    This paper addresses the quantification of the value of structural health monitoring (SHM) before its implementation for structural systems on the basis of its Value of Information (VoI). The value of SHM is calculated utilizing the Bayesian pre-posterior decision analysis modelling the structural...... life cycle performance, the integrity management and the structural risks. The relevance and precision of SHM information for the reduction of the structural system risks and the expected cost of the structural integrity management throughout the life cycle constitutes the value of SHM...... and is quantified with this framework. The approach is focused on fatigue deteriorating structural steel systems for which a continuous resistance deterioration formulation is introduced. In a case study, the value of SHM for load monitoring is calculated for a Daniels system subjected to fatigue deterioration...

  10. Validation of a Methodology to Predict Micro-Vibrations Based on Finite Element Model Approach

    Science.gov (United States)

    Soula, Laurent; Rathband, Ian; Laduree, Gregory

    2014-06-01

    This paper presents the second part of the ESA R&D study called "METhodology for Analysis of structure- borne MICro-vibrations" (METAMIC). After defining an integrated analysis and test methodology to help predicting micro-vibrations [1], a full-scale validation test campaign has been carried out. It is based on a bread-board representative of typical spacecraft (S/C) platform consisting in a versatile structure made of aluminium sandwich panels equipped with different disturbance sources and a dummy payload made of a silicon carbide (SiC) bench. The bread-board has been instrumented with a large set of sensitive accelerometers and tests have been performed including back-ground noise measurement, modal characterization and micro- vibration tests. The results provided responses to the perturbation coming from a reaction wheel or cryo-cooler compressors, operated independently then simultaneously with different operation modes. Using consistent modelling and associated experimental characterization techniques, a correlation status has been assessed by comparing test results with predictions based on FEM approach. Very good results have been achieved particularly for the case of a wheel in sweeping rate operation with test results over-predicted within a reasonable margin lower than two. Some limitations of the methodology have also been identified for sources operating at a fixed rate or coming with a small number of dominant harmonics and recommendations have been issued in order to deal with model uncertainties and stay conservative.

  11. Mental health consumer participation in education: a structured literature review.

    Science.gov (United States)

    Arblaster, Karen; Mackenzie, Lynette; Willis, Karen

    2015-10-01

    Consumer participation in design, delivery and evaluation of occupational therapy educational programs is a recently introduced requirement for accreditation. It aligns with the principle of recovery, which underpins Australian mental health policy. Graduates' capabilities for recovery-oriented practice are thought to be enhanced through learning from consumers' lived experience. This structured literature review evaluates the current evidence for mental health consumer participation in health professional education to inform occupational therapy educators. Searches were completed in five online databases, one journal and published reading lists on the topic. Studies were included if they addressed mental health consumer participation in health professional education programs, were published in peer reviewed journals between 2000 and 2014 and were in English. Articles were critically reviewed, and analysed for key findings related to stages of the educational process and recovery-oriented practice capabilities. An emerging body of evidence for consumer participation in mental health education was identified. Studies are characterised by a lack of quality and a low to medium level of evidence. Findings relate to design, planning, delivery and evaluation of education as well as to most aspects of recovery-oriented practice. Emphases on exploratory research and proximal outcomes, and a reliance on published outcome measurement instruments designed for other purposes are key limitations in this body of evidence. This study identifies a weak evidence base for the requirement for consumer participation in occupational therapy programs, specifically related to mental health curricula. A research agenda is proposed in response. © 2015 Occupational Therapy Australia.

  12. Development of a Vibration-Based Electromagnetic Energy Harvester by a Conductive Direct-Write Process

    Directory of Open Access Journals (Sweden)

    Yao-Yun Feng

    2017-03-01

    Full Text Available A conductive direct-write process of multilayered coils for micro electromagnetic generators is proposed. This novel approach of using silver ink to form the conductive structures largely reduces the fabrication complexity, and it provides a faster alternative to the conventional semiconductor methods. Multi-layered coils with insulation were accurately layered on a micromachined cantilevered diaphragm by a dispenser. Coils several layers thick could be used to increase the power output and double coils were separated by a layer of insulation. Six prototypes, all capable of efficient conversion of vibrational energy into electrical energy, were fabricated. The experimental results, which include measurements of the electromotive force and power output, are presented. Prototypes with two coils and thicker conducting layers had less resistance and the power output was much more than that of a single-coil unit. This generator can produce 82 nW of power at a resonance frequency of 275 Hz under 5 g excitation.

  13. Energy conversion by ‘T-shaped’ cantilever type electromagnetic vibration based micro power generator from low frequency vibration sources

    International Nuclear Information System (INIS)

    Siddique, Abu Raihan Mohammad; Mahmud, Shohel; Van Heyst, Bill

    2017-01-01

    Highlights: • A T-shaped cantilever type electromagnetic vibration based MPG has been described. • The designed EVMPG is useful for low frequency based vibration sources. • Both experimental tests and theoretical analysis have been performed. • The final compact prototype was tested at different conditions of human movements. • The prototype can generate 35.2 mV and 0.22 mW at 7 Hz with 5.6 Ω. - Abstract: The design, development, and analyses of low-frequency vibration based T-shaped cantilever type electromagnetic micro power generators (EVMPGs) are presented in this paper. Four different configurations (Configurations A to D) of EVMPGs were designed and fabricated and subsequently characterized using detailed experimental and limited analytical techniques. Configuration A and B consisted of a single and a double cylindrical moving magnets (NdFeB), respectively, while Configuration C consisted of four rectangular moving magnets with respect to a fixed copper coil. In contrast, Configuration D used a moving coil between four rectangular magnets with a back-iron bar. The open circuit RMS voltage output was observed to be a maximum from Configuration D (98.2 mV at 6.29 Hz) with a base vibration acceleration of 0.8 m s"−"2. Therefore, Configuration D was selected for further experimental investigations, which included changing the back-iron bar thickness, changing the base acceleration level, and changing the air gap separation between the magnets in order to optimize this configuration. The maximum load RMS voltage and power outputs of Configuration D were 105.4 mV and 1.35 mW at 6.29 Hz for load resistance 8.2 Ω and a base acceleration of 0.8 m s"−"2 with a 4.2 mm back-iron bar when the air gap between the magnets was 20 mm. Finally, a small portable EVMPG prototype was developed based on the Configuration D and was tested at different human movement conditions (i.e., walking, quick walking, and running). The developed EVMPG prototype was capable of

  14. Fiber Optic Thermal Health Monitoring of Aerospace Structures and Materials

    Science.gov (United States)

    Wu, Meng-Chou; Winfree, William P.; Allison, Sidney G.

    2009-01-01

    A new technique is presented for thermographic detection of flaws in materials and structures by performing temperature measurements with fiber Bragg gratings. Individual optical fibers with multiple Bragg gratings employed as surface temperature sensors were bonded to the surfaces of structures with subsurface defects or thickness variations. Both during and following the application of a thermal heat flux to the surface, the individual Bragg grating sensors measured the temporal and spatial temperature variations. The investigated structures included a 10-ply composite specimen with subsurface delaminations of various sizes and depths. The data obtained from grating sensors were further analyzed with thermal modeling to reveal particular characteristics of the interested areas. These results were found to be consistent with those from conventional thermography techniques. Limitations of the technique were investigated using both experimental and numerical simulation techniques. Methods for performing in-situ structural health monitoring are discussed.

  15. Multi-metric model-based structural health monitoring

    Science.gov (United States)

    Jo, Hongki; Spencer, B. F.

    2014-04-01

    ABSTRACT The inspection and maintenance of bridges of all types is critical to the public safety and often critical to the economy of a region. Recent advanced sensor technologies provide accurate and easy-to-deploy means for structural health monitoring and, if the critical locations are known a priori, can be monitored by direct measurements. However, for today's complex civil infrastructure, the critical locations are numerous and often difficult to identify. This paper presents an innovative framework for structural monitoring at arbitrary locations on the structure combining computational models and limited physical sensor information. The use of multi-metric measurements is advocated to improve the accuracy of the approach. A numerical example is provided to illustrate the proposed hybrid monitoring framework, particularly focusing on fatigue life assessment of steel structures.

  16. Structural Health Monitoring with Fiber Bragg Grating and Piezo Arrays

    Science.gov (United States)

    Black, Richard J.; Faridian, Ferey; Moslehi, Behzad; Sotoudeh, Vahid

    2012-01-01

    Structural health monitoring (SHM) is one of the most important tools available for the maintenance, safety, and integrity of aerospace structural systems. Lightweight, electromagnetic-interference- immune, fiber-optic sensor-based SHM will play an increasing role in more secure air transportation systems. Manufacturers and maintenance personnel have pressing needs for significantly improving safety and reliability while providing for lower inspection and maintenance costs. Undetected or untreated damage may grow and lead to catastrophic structural failure. Damage can originate from the strain/stress history of the material, imperfections of domain boundaries in metals, delamination in multi-layer materials, or the impact of machine tools in the manufacturing process. Damage can likewise develop during service life from wear and tear, or under extraordinary circumstances such as with unusual forces, temperature cycling, or impact of flying objects. Monitoring and early detection are key to preventing a catastrophic failure of structures, especially when these are expected to perform near their limit conditions.

  17. Vibration-Based Data Used to Detect Cracks in Rotating Disks

    Science.gov (United States)

    Gyekenyesi, Andrew L.; Sawicki, Jerzy T.; Martin, Richard E.; Baaklini, George Y.

    2004-01-01

    Rotor health monitoring and online damage detection are increasingly gaining the interest of aircraft engine manufacturers. This is primarily due to the fact that there is a necessity for improved safety during operation as well as a need for lower maintenance costs. Applied techniques for the damage detection and health monitoring of rotors are essential for engine safety, reliability, and life prediction. Recently, the United States set the ambitious goal of reducing the fatal accident rate for commercial aviation by 80 percent within 10 years. In turn, NASA, in collaboration with the Federal Aviation Administration, other Federal agencies, universities, and the airline and aircraft industries, responded by developing the Aviation Safety Program. This program provides research and technology products needed to help the aerospace industry achieve their aviation safety goal. The Nondestructive Evaluation (NDE) Group of the Optical Instrumentation Technology Branch at the NASA Glenn Research Center is currently developing propulsion-system-specific technologies to detect damage prior to catastrophe under the propulsion health management task. Currently, the NDE group is assessing the feasibility of utilizing real-time vibration data to detect cracks in turbine disks. The data are obtained from radial blade-tip clearance and shaft-clearance measurements made using capacitive or eddy-current probes. The concept is based on the fact that disk cracks distort the strain field within the component. This, in turn, causes a small deformation in the disk's geometry as well as a possible change in the system's center of mass. The geometric change and the center of mass shift can be indirectly characterized by monitoring the amplitude and phase of the first harmonic (i.e., the 1 component) of the vibration data. Spin pit experiments and full-scale engine tests have been conducted while monitoring for crack growth with this detection methodology. Even so, published data are

  18. Disadvantaged persons' participation in health promotion projects: some structural dimensions.

    Science.gov (United States)

    Boyce, W F

    2001-05-01

    A structural perspective was used in studying community participation of disadvantaged groups (poor women, street youth, and disabled persons) in health promotion projects. Five community projects in the Canadian Health Promotion Contribution Program were examined in a comparative case study utilizing in-depth interviews, documents, and secondary sources. Analysis revealed relatively low numbers and restricted range of participants, difficulties in recruiting and maintaining participants, declining rates of active participation over time, and limited target group influence and power. This paper reports on the relationship between various dimensions of structure (social-cultural, organizational, political-legal-economic) and the community participation process. Participation was influenced by structural factors such as bureaucratic rules and regulators, perceived minority group rights and relations, agency reputations and responsibilities, available resources, and organizational roles. Control of projects by target group members, rather than by service agencies, was an important overall organizational structural factor which allowed community members to achieve influence in projects. The study concludes that a conceptual model based on structural factors is useful in explaining how key factors from federal and local levels can restrict or facilitate the community participation process.

  19. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead they grow up in single parent households or in families with a step-parent. Hence it is important to improve our understanding of the impact of 'shocks' in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized by shocks in the family structure during childhood. I focus on both educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1983, 1984, and 1985 is used for the analysis...

  20. Vibration-Based Adaptive Novelty Detection Method for Monitoring Faults in a Kinematic Chain

    Directory of Open Access Journals (Sweden)

    Jesus Adolfo Cariño-Corrales

    2016-01-01

    Full Text Available This paper presents an adaptive novelty detection methodology applied to a kinematic chain for the monitoring of faults. The proposed approach has the premise that only information of the healthy operation of the machine is initially available and fault scenarios will eventually develop. This approach aims to cover some of the challenges presented when condition monitoring is applied under a continuous learning framework. The structure of the method is divided into two recursive stages: first, an offline stage for initialization and retraining of the feature reduction and novelty detection modules and, second, an online monitoring stage to continuously assess the condition of the machine. Contrary to classical static feature reduction approaches, the proposed method reformulates the features by employing first a Laplacian Score ranking and then the Fisher Score ranking for retraining. The proposed methodology is validated experimentally by monitoring the vibration measurements of a kinematic chain driven by an induction motor. Two faults are induced in the motor to validate the method performance to detect anomalies and adapt the feature reduction and novelty detection modules to the new information. The obtained results show the advantages of employing an adaptive approach for novelty detection and feature reduction making the proposed method suitable for industrial machinery diagnosis applications.

  1. Damage Detection with Streamlined Structural Health Monitoring Data

    OpenAIRE

    Li, Jian; Deng, Jun; Xie, Weizhi

    2015-01-01

    The huge amounts of sensor data generated by large scale sensor networks in on-line structural health monitoring (SHM) systems often overwhelms the systems’ capacity for data transmission and analysis. This paper presents a new concept for an integrated SHM system in which a streamlined data flow is used as a unifying thread to integrate the individual components of on-line SHM systems. Such an integrated SHM system has a few desirable functionalities including embedded sensor data compressio...

  2. Formalized Medical Guidelines and a Structured Electronic Health Record.

    Czech Academy of Sciences Publication Activity Database

    Peleška, Jan; Anger, Z.; Buchtela, David; Šebesta, K.; Tomečková, Marie; Veselý, Arnošt; Zvára, K.; Zvárová, Jana

    2005-01-01

    Roč. 11, - (2005), s. 4652-4656 ISSN 1727-1983. [EMBEC'05. European Medical and Biomedical Conference /3./. Prague, 20.11.2005-25.11.2005] R&D Projects: GA AV ČR 1ET200300413 Institutional research plan: CEZ:AV0Z10300504 Keywords : formalization of guidelines in cardilogy * GLIF model * structure electronic health record * algorithm in cardiovascular diagnostics and treatment Subject RIV: BD - Theory of Information

  3. Bayesian Computational Sensor Networks for Aircraft Structural Health Monitoring

    Science.gov (United States)

    2016-02-02

    Virginia 22203 Air Force Research Laboratory Air Force Materiel Command 1 Final Performance Report: AFOSR T.C. Henderson , V.J. Mathews, and D...AFRL-AFOSR-VA-TR-2016-0094 Bayesian Computational Sensor Networks for Aircraft Structural Health Monitoring. Thomas Henderson UNIVERSITY OF UTAH SALT...The people who worked on this project include: Thomas C. Henderson , John Mathews, Jingru Zhou, Daimei Zhij, Ahmad Zoubi, Sabita Nahata, Dan Adams

  4. Structural health monitoring of compression connectors for overhead transmission lines

    Science.gov (United States)

    Wang, Hong; Wang, Jy-An John; Swindeman, Joseph P.; Ren, Fei; Chan, John

    2017-04-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over electrical conducting aluminum strands. The connectors are designed to operate at temperatures up to 125°C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements, but these methods do not provide information about the structural integrity of connectors. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to induce structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  5. Investigation of Effectiveness of Some Vibration-Based Techniques in Early Detection of Real-Time Fatigue Failure in Gears

    Directory of Open Access Journals (Sweden)

    Hasan Ozturk

    2010-01-01

    Full Text Available Bending fatigue crack is a dangerous and insidious mode of failure in gears. As it produces no debris in its early stages, it gives little warning during its progression, and usually results in either immediate loss of serviceability or greatly reduced power transmitting capacity. This paper presents the applications of vibration-based techniques (i.e. conventional time and frequency domain analysis, cepstrum, and continuous wavelet transform to real gear vibrations in the early detection, diagnosis and advancement monitoring of a real tooth fatigue crack and compares their detection and diagnostic capabilities on the basis of experimental results. Gear fatigue damage is achieved under heavy-loading conditions and the gearbox is allowed to run until the gears suffer badly from complete tooth breakage. It has been found that the initiation and progression of fatigue crack cannot be easily detected by conventional time and frequency domain approaches until the fault is significantly developed. On the contrary, the wavelet transform is quite sensitive to any change in gear vibration and reveals fault features earlier than other methods considered.

  6. Ultrasonic guided wave interpretation for structural health inspections

    Science.gov (United States)

    Bingham, Jill Paisley

    Structural Health Management (SHM) combines the use of onboard sensors with artificial intelligence algorithms to automatically identify and monitor structural health issues. A fully integrated approach to SHM systems demands an understanding of the sensor output relative to the structure, along with sophisticated prognostic systems that automatically draw conclusions about structural integrity issues. Ultrasonic guided wave methods allow us to examine the interaction of multimode signals within key structural components. Since they propagate relatively long distances within plate- and shell-like structures, guided waves allow inspection of greater areas with fewer sensors, making this technique attractive for a variety of applications. This dissertation describes the experimental development of automatic guided wave interpretation for three real world applications. Using the guided wave theories for idealized plates we have systematically developed techniques for identifying the mass loading of underwater limpet mines on US Navy ship hulls, characterizing type and bonding of protective coatings on large diameter pipelines, and detecting the thinning effects of corrosion on aluminum aircraft structural stringers. In each of these circumstances the signals received are too complex for interpretation without knowledge of the guided wave physics. We employ a signal processing technique called the Dynamic Wavelet Fingerprint Technique (DFWT) in order to render the guided wave mode information in two-dimensional binary images. The use of wavelets allows us to keep track of both time and scale features from the original signals. With simple image processing we have developed automatic extraction algorithms for features that correspond to the arrival times of the guided wave modes of interest for each of the applications. Due to the dispersive nature of the guided wave modes, the mode arrival times give details of the structure in the propagation path. For further

  7. Implementing optical fibres for the structural health monitoring of composite patch repaired structures

    DEFF Research Database (Denmark)

    Karatzas, Vasileios; Kotsidis, Elias A.; Tsouvalis, Nicholas G.

    2017-01-01

    Structural health monitoring is increasingly being implemented to improve the level of safety of structures and to reduce inspection and repair costs by allowing for correct planning of these actions, if needed. Composite patch repairing presents an appealing alternative to traditional repair...... methods as it enables the reduction of closedown time and the mitigation of complications associated with traditional repair methods. As reinforcement with the use of composite patches is predominantly performed at defected structures, the urge to monitor the performance of the repair becomes even greater...

  8. Regeneration and health: a structured, rapid literature review.

    Science.gov (United States)

    McCartney, G; Hearty, W; Taulbut, M; Mitchell, R; Dryden, R; Collins, C

    2017-07-01

    To identify and synthesise what is known about the impacts of regeneration on health, health inequalities and their socio-economic determinants. Rapid, structured literature review. A rapid, structured approach was undertaken to identifying relevant studies involving a search of peer-reviewed literature databases, an Internet search to identify relevant grey literature, and a review of articles citing two key systematic reviews. The identified citations were screened, critically appraised according to the research design and narratively synthesised. Of the 1382 identified citations, 46 were screened as relevant to the review and included in the synthesis. Fifteen citations were reviews but most of the evidence identified or included within the reviews was of medium or low quality due to a lack of longitudinal follow-up, low response rates or attrition. The evidence base on the impacts of regeneration is generally not of high quality and is prone to bias. However, it is theorised as being an important means of addressing the socio-economic determinants of health. Housing refurbishment (generally, and for specific improvements) seems likely to lead to small improvements in health, whereas rehousing and mixed-tenure approaches have less clear impacts on health and carry risks of disruption to social networks and higher rents. Changes in the social composition of communities (gentrification) is a common outcome of regeneration and some 'partnership' approaches to regeneration have been shown to have caused difficulties within communities. The evidence base for regeneration activities is limited but they have substantial potential to contribute to improving population health. Better quality evidence is available for there being positive health impacts from housing-led regeneration programmes involving refurbishment and specific housing improvements. There is also some evidence of the potential harms of regeneration activities, including social stratification

  9. Passive and Active Sensing Technologies for Structural Health Monitoring

    Science.gov (United States)

    Do, Richard

    A combination of passive and active sensing technologies is proposed as a structural health monitoring solution for several applications. Passive sensing is differentiated from active sensing in that with the former, no energy is intentionally imparted into the structure under test; sensors are deployed in a pure detection mode for collecting data mined for structural health monitoring purposes. In this thesis, passive sensing using embedded fiber Bragg grating optical strain gages was used to detect varying degrees of impact damage using two different classes of features drawn from traditional spectral analysis and auto-regressive time series modeling. The two feature classes were compared in detail through receiver operating curve performance analysis. The passive detection problem was then augmented with an active sensing system using ultrasonic guided waves (UGWs). This thesis considered two main challenges associated with UGW SHM including in-situ wave propagation property determination and thermal corruption of data. Regarding determination of wave propagation properties, of which dispersion characteristics are the most important, a new dispersion curve extraction method called sparse wavenumber analysis (SWA) was experimentally validated. Also, because UGWs are extremely sensitive to ambient temperature changes on the structure, it significantly affects the wave propagation properties by causing large errors in the residual error in the processing of the UGWs from an array. This thesis presented a novel method that compensates for uniform temperature change by considering the magnitude and phase of the signal separately and applying a scalable transformation.

  10. Structure health monitoring system using internet and database technologies

    International Nuclear Information System (INIS)

    Kwon, Il Bum; Kim, Chi Yeop; Choi, Man Yong; Lee, Seung Seok

    2003-01-01

    Structural health monitoring system should developed to be based on internet and database technology in order to manage efficiently large structures. This system is operated by internet connected with the side of structures. The monitoring system has some functions: self monitoring, self diagnosis, and self control etc. Self monitoring is the function of sensor fault detection. If some sensors are not normally worked, then this system can detect the fault sensors. Also Self diagnosis function repair the abnormal condition of sensors. And self control is the repair function of the monitoring system. Especially, the monitoring system can identify the replacement of sensors. For further study, the real application test will be performed to check some unconvince.

  11. Structural health monitoring system using internet and database technologies

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chi Yeop; Choi, Man Yong; Kwon, Il Bum; Lee, Seung Seok [Nonstructive Measurment Lab., KRISS, Daejeon (Korea, Republic of)

    2003-07-01

    Structure health monitoring system should develope to be based on internet and database technology in order to manage efficiency large structures. This system is operated by internet connected with the side of structures. The monitoring system has some functions: self monitoring, self diagnosis, and self control etc. Self monitoring is the function of sensor fault detection. If some sensors are not normally worked, then this system can detect the fault sensors. Also Self diagnosis function repair the abnormal condition of sensors. And self control is the repair function of the monitoring system. Especially, the monitoring system can identify the replacement of sensors. For further study, the real application test will be performed to check some unconviniences.

  12. Structure health monitoring system using internet and database technologies

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Il Bum; Kim, Chi Yeop; Choi, Man Yong; Lee, Seung Seok [Smart Measurment Group. Korea Resarch Institute of Standards and Science, Saejeon (Korea, Republic of)

    2003-05-15

    Structural health monitoring system should developed to be based on internet and database technology in order to manage efficiently large structures. This system is operated by internet connected with the side of structures. The monitoring system has some functions: self monitoring, self diagnosis, and self control etc. Self monitoring is the function of sensor fault detection. If some sensors are not normally worked, then this system can detect the fault sensors. Also Self diagnosis function repair the abnormal condition of sensors. And self control is the repair function of the monitoring system. Especially, the monitoring system can identify the replacement of sensors. For further study, the real application test will be performed to check some unconvince.

  13. Structural health monitoring system using internet and database technologies

    International Nuclear Information System (INIS)

    Kim, Chi Yeop; Choi, Man Yong; Kwon, Il Bum; Lee, Seung Seok

    2003-01-01

    Structure health monitoring system should develope to be based on internet and database technology in order to manage efficiency large structures. This system is operated by internet connected with the side of structures. The monitoring system has some functions: self monitoring, self diagnosis, and self control etc. Self monitoring is the function of sensor fault detection. If some sensors are not normally worked, then this system can detect the fault sensors. Also Self diagnosis function repair the abnormal condition of sensors. And self control is the repair function of the monitoring system. Especially, the monitoring system can identify the replacement of sensors. For further study, the real application test will be performed to check some unconviniences.

  14. Probabilistic Structural Health Monitoring of the Orbiter Wing Leading Edge

    Science.gov (United States)

    Yap, Keng C.; Macias, Jesus; Kaouk, Mohamed; Gafka, Tammy L.; Kerr, Justin H.

    2011-01-01

    A structural health monitoring (SHM) system can contribute to the risk management of a structure operating under hazardous conditions. An example is the Wing Leading Edge Impact Detection System (WLEIDS) that monitors the debris hazards to the Space Shuttle Orbiter s Reinforced Carbon-Carbon (RCC) panels. Since Return-to-Flight (RTF) after the Columbia accident, WLEIDS was developed and subsequently deployed on board the Orbiter to detect ascent and on-orbit debris impacts, so as to support the assessment of wing leading edge structural integrity prior to Orbiter re-entry. As SHM is inherently an inverse problem, the analyses involved, including those performed for WLEIDS, tend to be associated with significant uncertainty. The use of probabilistic approaches to handle the uncertainty has resulted in the successful implementation of many development and application milestones.

  15. Parenting Stress, Mental Health, Dyadic Adjustment: A Structural Equation Model

    Directory of Open Access Journals (Sweden)

    Luca Rollè

    2017-05-01

    Full Text Available Objective: In the 1st year of the post-partum period, parenting stress, mental health, and dyadic adjustment are important for the wellbeing of both parents and the child. However, there are few studies that analyze the relationship among these three dimensions. The aim of this study is to investigate the relationships between parenting stress, mental health (depressive and anxiety symptoms, and dyadic adjustment among first-time parents.Method: We studied 268 parents (134 couples of healthy babies. At 12 months post-partum, both parents filled out, in a counterbalanced order, the Parenting Stress Index-Short Form, the Edinburgh Post-natal Depression Scale, the State-Trait Anxiety Inventory, and the Dyadic Adjustment Scale. Structural equation modeling was used to analyze the potential mediating effects of mental health on the relationship between parenting stress and dyadic adjustment.Results: Results showed the full mediation effect of mental health between parenting stress and dyadic adjustment. A multi-group analysis further found that the paths did not differ across mothers and fathers.Discussion: The results suggest that mental health is an important dimension that mediates the relationship between parenting stress and dyadic adjustment in the transition to parenthood.

  16. Structural Health Monitoring of Nuclear Spent Fuel Storage Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lingyu

    2018-04-10

    Interim storage of spent nuclear fuel from reactor sites has gained additional importance and urgency for resolving waste-management-related technical issues. To ensure that nuclear power remains clean energy, monitoring has been identified by DOE as a high priority cross-cutting need, necessary to determine and predict the degradation state of the systems, structures, and components (SSCs) important to safety (ITS). Therefore, nondestructive structural condition monitoring becomes a need to be installed on existing or to be integrated into future storage system to quantify the state of health or to guarantee the safe operation of nuclear power plants (NPPs) during their extended life span. In this project, the lead university and the collaborating national laboratory teamed to develop a nuclear structural health monitoring (n-SHM) system based on in-situ piezoelectric sensing technologies that can monitor structural degradation and aging for nuclear spent fuel DCSS and similar structures. We also aimed to identify and quantify possible influences of nuclear spent fuel environment (temperature and radiation) to the piezoelectric sensor system and come up with adequate solutions and guidelines therefore. We have therefore developed analytical model for piezoelectric based n-SHM methods, with considerations of temperature and irradiation influence on the model of sensing and algorithms in acoustic emission (AE), guided ultrasonic waves (GUW), and electromechanical impedance spectroscopy (EMIS). On the other side, experimentally the temperature and irradiation influence on the piezoelectric sensors and sensing capabilities were investigated. Both short-term and long-term irradiation investigation with our collaborating national laboratory were performed. Moreover, we developed multi-modal sensing, validated in laboratory setup, and conducted the testing on the We performed multi-modal sensing development, verification and validation tests on very complex structures

  17. Designing food structures for nutrition and health benefits.

    Science.gov (United States)

    Norton, Jennifer E; Wallis, Gareth A; Spyropoulos, Fotis; Lillford, Peter J; Norton, Ian T

    2014-01-01

    In addition to providing specific sensory properties (e.g., flavor or textures), there is a need to produce foods that also provide functionality within the gastrointestinal (GI) tract, over and above simple nutrition. As such, there is a need to understand the physical and chemical processes occurring in the mouth, stomach, small intestine, and large intestine, in addition to the food structure-physiology interactions. In vivo techniques and in vitro models have allowed us to study and simulate these processes, which aids us in the design of food microstructures that can provide functionality within the human body. Furthermore, it is important to be aware of the health or nutritional needs of different groups of consumers when designing food structures, to provide targeted functionality. Examples of three groups of consumers (elderly, obese, and athletes) are given to demonstrate their differing nutritional requirements and the formulation engineering approaches that can be utilized to improve the health of these individuals. Eating is a pleasurable process, but foods of the future will be required to provide much more in terms of functionality for health and nutrition.

  18. Structural Health Monitoring of Transport Aircraft with Fuzzy Logic Modeling

    Directory of Open Access Journals (Sweden)

    Ray C. Chang

    2013-01-01

    Full Text Available A structural health monitoring method based on the concept of static aeroelasticity is presented in this paper. This paper focuses on the estimation of these aeroelastic effects on older transport aircraft, in particular the structural components that are most affected, in severe atmospheric turbulence. Because the structural flexibility properties are mostly unknown to aircraft operators, only the trend, not the magnitude, of these effects is estimated. For this purpose, one useful concept in static aeroelastic effects for conventional aircraft structures is that under aeroelastic deformation the aerodynamic center should move aft. This concept is applied in the present paper by using the fuzzy-logic aerodynamic models. A twin-jet transport aircraft in severe atmospheric turbulence involving plunging motion is examined. It is found that the pitching moment derivatives in cruise with moderate to severe turbulence in transonic flight indicate some degree of abnormality in the stabilizer (i.e., the horizontal tail. Therefore, the horizontal tail is the most severely affected structural component of the aircraft probably caused by vibration under the dynamic loads induced by turbulence.

  19. Improved Stochastic Subspace System Identification for Structural Health Monitoring

    Science.gov (United States)

    Chang, Chia-Ming; Loh, Chin-Hsiung

    2015-07-01

    Structural health monitoring acquires structural information through numerous sensor measurements. Vibrational measurement data render the dynamic characteristics of structures to be extracted, in particular of the modal properties such as natural frequencies, damping, and mode shapes. The stochastic subspace system identification has been recognized as a power tool which can present a structure in the modal coordinates. To obtain qualitative identified data, this tool needs to spend computational expense on a large set of measurements. In study, a stochastic system identification framework is proposed to improve the efficiency and quality of the conventional stochastic subspace system identification. This framework includes 1) measured signal processing, 2) efficient space projection, 3) system order selection, and 4) modal property derivation. The measured signal processing employs the singular spectrum analysis algorithm to lower the noise components as well as to present a data set in a reduced dimension. The subspace is subsequently derived from the data set presented in a delayed coordinate. With the proposed order selection criteria, the number of structural modes is determined, resulting in the modal properties. This system identification framework is applied to a real-world bridge for exploring the feasibility in real-time applications. The results show that this improved system identification method significantly decreases computational time, while qualitative modal parameters are still attained.

  20. Wireless Zigbee strain gage sensor system for structural health monitoring

    Science.gov (United States)

    Ide, Hiroshi; Abdi, Frank; Miraj, Rashid; Dang, Chau; Takahashi, Tatsuya; Sauer, Bruce

    2009-05-01

    A compact cell phone size radio frequency (ZigBee) wireless strain measurement sensor system to measure the structural strain deformation was developed. The developed system provides an accurate strain measurement data stream to the Internet for further Diagnostic and Prognostic (DPS) correlation. Existing methods of structural measurement by strain sensors (gauges) do not completely satisfy problems posed by continuous structural health monitoring. The need for efficient health monitoring methods with real-time requirements to bidirectional data flow from sensors and to a commanding device is becoming critical for keeping our daily life safety. The use of full-field strain measurement techniques could reduce costly experimental programs through better understanding of material behavior. Wireless sensor-network technology is a monitoring method that is estimated to grow rapidly providing potential for cost savings over traditional wired sensors. The many of currently available wireless monitoring methods have: the proactive and constant data rate character of the data streams rather than traditional reactive, event-driven data delivery; mostly static node placement on structures with limited number of nodes. Alpha STAR Electronics' wireless sensor network system, ASWN, addresses some of these deficiencies, making the system easier to operate. The ASWN strain measurement system utilizes off-the-shelf sensors, namely strain gauges, with an analog-to-digital converter/amplifier and ZigBee radio chips to keep cost lower. Strain data is captured by the sensor, converted to digital form and delivered to the ZigBee radio chip, which in turn broadcasts the information using wireless protocols to a Personal Data Assistant (PDA) or Laptop/Desktop computers. From here, data is forwarded to remote computers for higher-level analysis and feedback using traditional cellular and satellite communication or the Ethernet infrastructure. This system offers a compact size, lower cost

  1. Structural developmental psychology and health promotion in the third age.

    Science.gov (United States)

    Bauger, Lars; Bongaardt, Rob

    2017-01-12

    In response to the ever-increasing longevity in Western societies, old age has been divided into two different periods, labelled the third and fourth age. Where the third age, with its onset at retirement, mostly involves positive aspects of growing old, the fourth age involves functional decline and increased morbidity. This article focuses on the entry to the third age and its potential for health promotion initiatives. Well-being is an important factor to emphasize in such health promotion, and this article views the lifestyle of third agers as essential for their well-being. The structural developmental theory of Robert Kegan delineates how a person's way of knowing develops throughout the life course. This theory is an untapped and salient perspective for health promotion initiatives in the third age. This article outlines Kegan's approach as a tool for developing psychologically spacious health promotion, and suggests future directions for research on the topic. © The Author 2017. Published by Oxford University Press.

  2. Investigation of Wireless Sensor Networks for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2012-01-01

    Full Text Available Wireless sensor networks (WSNs are one of the most able technologies in the structural health monitoring (SHM field. Through intelligent, self-organising means, the contents of this paper will test a variety of different objects and different working principles of sensor nodes connected into a network and integrated with data processing functions. In this paper the key issues of WSN applied in SHM are discussed, including the integration of different types of sensors with different operational modalities, sampling frequencies, issues of transmission bandwidth, real-time ability, and wireless transmitter frequency. Furthermore, the topology, data fusion, integration, energy saving, and self-powering nature of different systems will be investigated. In the FP7 project “Health Monitoring of Offshore Wind Farms,” the above issues are explored.

  3. Structural Health Monitoring of Bridges with Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Francisco Navarro-Henríquez

    2014-11-01

    Systems with fiber optic sensors FBG (Fiber Bragg Grating are consolidated in the Structural Health Monitoring (SMH of bridges, Nondestructive Testing (NDT static and dynamic measurements of deformation, displacement, deflection, temperature and vibration. This article provides a brief introduction to the technology and the fundamentals of fiber optic sensors, also present comparative advantages over its traditional counterpart is presented. Their characteristics are described and measurement graphics are presented as an application example of the FBG sensors. Finally, some key aspects to consider for proper use in the field are mentioned.

  4. Structural Health Monitoring Analysis for the Orbiter Wing Leading Edge

    Science.gov (United States)

    Yap, Keng C.

    2010-01-01

    This viewgraph presentation reviews Structural Health Monitoring Analysis for the Orbiter Wing Leading Edge. The Wing Leading Edge Impact Detection System (WLE IDS) and the Impact Analysis Process are also described to monitor WLE debris threats. The contents include: 1) Risk Management via SHM; 2) Hardware Overview; 3) Instrumentation; 4) Sensor Configuration; 5) Debris Hazard Monitoring; 6) Ascent Response Summary; 7) Response Signal; 8) Distribution of Flight Indications; 9) Probabilistic Risk Analysis (PRA); 10) Model Correlation; 11) Impact Tests; 12) Wing Leading Edge Modeling; 13) Ascent Debris PRA Results; and 14) MM/OD PRA Results.

  5. Review on pressure sensors for structural health monitoring

    Science.gov (United States)

    Sikarwar, Samiksha; Satyendra; Singh, Shakti; Yadav, Bal Chandra

    2017-12-01

    This paper reports the state of art in a variety of pressure and the detailed study of various matrix based pressure sensors. The performances of the bridges, buildings, etc. are threatened by earthquakes, material degradations, and other environmental effects. Structural health monitoring (SHM) is crucial to protect the people and also for assets planning. This study is a contribution in developing the knowledge about self-sensing smart materials and structures for the construction industry. It deals with the study of self-sensing as well as mechanical and electrical properties of different matrices based on pressure sensors. The relationships among the compression, tensile strain, and crack length with electrical resistance change are also reviewed.

  6. Time-Frequency Methods for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Alexander L. Pyayt

    2014-03-01

    Full Text Available Detection of early warning signals for the imminent failure of large and complex engineered structures is a daunting challenge with many open research questions. In this paper we report on novel ways to perform Structural Health Monitoring (SHM of flood protection systems (levees, earthen dikes and concrete dams using sensor data. We present a robust data-driven anomaly detection method that combines time-frequency feature extraction, using wavelet analysis and phase shift, with one-sided classification techniques to identify the onset of failure anomalies in real-time sensor measurements. The methodology has been successfully tested at three operational levees. We detected a dam leakage in the retaining dam (Germany and “strange” behaviour of sensors installed in a Boston levee (UK and a Rhine levee (Germany.

  7. Active sensors for health monitoring of aging aerospace structures

    Science.gov (United States)

    Giurgiutiu, Victor; Redmond, James M.; Roach, Dennis P.; Rackow, Kirk

    2000-06-01

    A project to develop non-intrusive active sensors that can be applied on existing aging aerospace structures for monitoring the onset and progress of structural damage (fatigue cracks and corrosion) is presented. The state of the art in active sensors structural health monitoring and damage detection is reviewed. Methods based on (a) elastic wave propagation and (b) electro-mechanical (E/M) impedance technique are cited and briefly discussed. The instrumentation of these specimens with piezoelectric active sensors is illustrated. The main detection strategies (E/M impedance for local area detection and wave propagation for wide area interrogation) are discussed. The signal processing and damage interpretation algorithms are tuned to the specific structural interrogation method used. In the high frequency E/M impedance approach, pattern recognition methods are used to compare impedance signatures taken at various time intervals and to identify damage presence and progression from the change in these signatures. In the wave propagation approach, the acousto- ultrasonic methods identifying additional reflection generated from the damage site and changes in transmission velocity and phase are used. Both approaches benefit from the use of artificial intelligence neural networks algorithms that can extract damage features based on a learning process. Design and fabrication of a set of structural specimens representative of aging aerospace structures is presented. Three built-up specimens, (pristine, with cracks, and with corrosion damage) are used. The specimen instrumentation with active sensors fabricated at the University of South Carolina is illustrated. Preliminary results obtained with the E/M impedance method on pristine and cracked specimens are presented.

  8. A bio-inspired memory model for structural health monitoring

    Science.gov (United States)

    Zheng, Wei; Zhu, Yong

    2009-04-01

    Long-term structural health monitoring (SHM) systems need intelligent management of the monitoring data. By analogy with the way the human brain processes memories, we present a bio-inspired memory model (BIMM) that does not require prior knowledge of the structure parameters. The model contains three time-domain areas: a sensory memory area, a short-term memory area and a long-term memory area. First, the initial parameters of the structural state are specified to establish safety criteria. Then the large amount of monitoring data that falls within the safety limits is filtered while the data outside the safety limits are captured instantly in the sensory memory area. Second, disturbance signals are distinguished from danger signals in the short-term memory area. Finally, the stable data of the structural balance state are preserved in the long-term memory area. A strategy for priority scheduling via fuzzy c-means for the proposed model is then introduced. An experiment on bridge tower deformation demonstrates that the proposed model can be applied for real-time acquisition, limited-space storage and intelligent mining of the monitoring data in a long-term SHM system.

  9. A bio-inspired memory model for structural health monitoring

    International Nuclear Information System (INIS)

    Zheng, Wei; Zhu, Yong

    2009-01-01

    Long-term structural health monitoring (SHM) systems need intelligent management of the monitoring data. By analogy with the way the human brain processes memories, we present a bio-inspired memory model (BIMM) that does not require prior knowledge of the structure parameters. The model contains three time-domain areas: a sensory memory area, a short-term memory area and a long-term memory area. First, the initial parameters of the structural state are specified to establish safety criteria. Then the large amount of monitoring data that falls within the safety limits is filtered while the data outside the safety limits are captured instantly in the sensory memory area. Second, disturbance signals are distinguished from danger signals in the short-term memory area. Finally, the stable data of the structural balance state are preserved in the long-term memory area. A strategy for priority scheduling via fuzzy c-means for the proposed model is then introduced. An experiment on bridge tower deformation demonstrates that the proposed model can be applied for real-time acquisition, limited-space storage and intelligent mining of the monitoring data in a long-term SHM system

  10. Structural health monitoring methodology for aircraft condition-based maintenance

    Science.gov (United States)

    Saniger, Jordi; Reithler, Livier; Guedra-Degeorges, Didier; Takeda, Nobuo; Dupuis, Jean Pierre

    2001-06-01

    Reducing maintenance costs while keeping a constant level of safety is a major issue for Air Forces and airlines. The long term perspective is to implement condition based maintenance to guarantee a constant safety level while decreasing maintenance costs. On this purpose, the development of a generalized Structural Health Monitoring System (SHMS) is needed. The objective of such a system is to localize the damages and to assess their severity, with enough accuracy to allow low cost corrective actions. The present paper describes a SHMS based on acoustic emission technology. This choice was driven by its reliability and wide use in the aerospace industry. The described SHMS uses a new learning methodology which relies on the generation of artificial acoustic emission events on the structure and an acoustic emission sensor network. The calibrated acoustic emission events picked up by the sensors constitute the knowledge set that the system relies on. With this methodology, the anisotropy of composite structures is taken into account, thus avoiding the major cause of errors of classical localization methods. Moreover, it is adaptive to different structures as it does not rely on any particular model but on measured data. The acquired data is processed and the event's location and corrected amplitude are computed. The methodology has been demonstrated and experimental tests on elementary samples presented a degree of accuracy of 1cm.

  11. Simulation tools for guided wave based structural health monitoring

    Science.gov (United States)

    Mesnil, Olivier; Imperiale, Alexandre; Demaldent, Edouard; Baronian, Vahan; Chapuis, Bastien

    2018-04-01

    Structural Health Monitoring (SHM) is a thematic derived from Non Destructive Evaluation (NDE) based on the integration of sensors onto or into a structure in order to monitor its health without disturbing its regular operating cycle. Guided wave based SHM relies on the propagation of guided waves in plate-like or extruded structures. Using piezoelectric transducers to generate and receive guided waves is one of the most widely accepted paradigms due to the low cost and low weight of those sensors. A wide range of techniques for flaw detection based on the aforementioned setup is available in the literature but very few of these techniques have found industrial applications yet. A major difficulty comes from the sensitivity of guided waves to a substantial number of parameters such as the temperature or geometrical singularities, making guided wave measurement difficult to analyze. In order to apply guided wave based SHM techniques to a wider spectrum of applications and to transfer those techniques to the industry, the CEA LIST develops novel numerical methods. These methods facilitate the evaluation of the robustness of SHM techniques for multiple applicative cases and ease the analysis of the influence of various parameters, such as sensors positioning or environmental conditions. The first numerical tool is the guided wave module integrated to the commercial software CIVA, relying on a hybrid modal-finite element formulation to compute the guided wave response of perturbations (cavities, flaws…) in extruded structures of arbitrary cross section such as rails or pipes. The second numerical tool is based on the spectral element method [2] and simulates guided waves in both isotropic (metals) and orthotropic (composites) plate like-structures. This tool is designed to match the widely accepted sparse piezoelectric transducer array SHM configuration in which each embedded sensor acts as both emitter and receiver of guided waves. This tool is under development and

  12. Integration of structural health monitoring solutions onto commercial aircraft via the Federal Aviation Administration structural health monitoring research program

    Science.gov (United States)

    Swindell, Paul; Doyle, Jon; Roach, Dennis

    2017-02-01

    The Federal Aviation Administration (FAA) started a research program in structural health monitoring (SHM) in 2011. The program's goal was to understand the technical gaps of implementing SHM on commercial aircraft and the potential effects on FAA regulations and guidance. The program evolved into a demonstration program consisting of a team from Sandia National Labs Airworthiness Assurance NDI Center (AANC), the Boeing Corporation, Delta Air Lines, Structural Monitoring Systems (SMS), Anodyne Electronics Manufacturing Corp (AEM) and the FAA. This paper will discuss the program from the selection of the inspection problem, the SHM system (Comparative Vacuum Monitoring-CVM) that was selected as the inspection solution and the testing completed to provide sufficient data to gain the first approved use of an SHM system for routine maintenance on commercial US aircraft.

  13. Design and Analysis of Architectures for Structural Health Monitoring Systems

    Science.gov (United States)

    Mukkamala, Ravi; Sixto, S. L. (Technical Monitor)

    2002-01-01

    During the two-year project period, we have worked on several aspects of Health Usage and Monitoring Systems for structural health monitoring. In particular, we have made contributions in the following areas. 1. Reference HUMS architecture: We developed a high-level architecture for health monitoring and usage systems (HUMS). The proposed reference architecture is shown. It is compatible with the Generic Open Architecture (GOA) proposed as a standard for avionics systems. 2. HUMS kernel: One of the critical layers of HUMS reference architecture is the HUMS kernel. We developed a detailed design of a kernel to implement the high level architecture.3. Prototype implementation of HUMS kernel: We have implemented a preliminary version of the HUMS kernel on a Unix platform.We have implemented both a centralized system version and a distributed version. 4. SCRAMNet and HUMS: SCRAMNet (Shared Common Random Access Memory Network) is a system that is found to be suitable to implement HUMS. For this reason, we have conducted a simulation study to determine its stability in handling the input data rates in HUMS. 5. Architectural specification.

  14. Architectural frameworks: defining the structures for implementing learning health systems.

    Science.gov (United States)

    Lessard, Lysanne; Michalowski, Wojtek; Fung-Kee-Fung, Michael; Jones, Lori; Grudniewicz, Agnes

    2017-06-23

    The vision of transforming health systems into learning health systems (LHSs) that rapidly and continuously transform knowledge into improved health outcomes at lower cost is generating increased interest in government agencies, health organizations, and health research communities. While existing initiatives demonstrate that different approaches can succeed in making the LHS vision a reality, they are too varied in their goals, focus, and scale to be reproduced without undue effort. Indeed, the structures necessary to effectively design and implement LHSs on a larger scale are lacking. In this paper, we propose the use of architectural frameworks to develop LHSs that adhere to a recognized vision while being adapted to their specific organizational context. Architectural frameworks are high-level descriptions of an organization as a system; they capture the structure of its main components at varied levels, the interrelationships among these components, and the principles that guide their evolution. Because these frameworks support the analysis of LHSs and allow their outcomes to be simulated, they act as pre-implementation decision-support tools that identify potential barriers and enablers of system development. They thus increase the chances of successful LHS deployment. We present an architectural framework for LHSs that incorporates five dimensions-goals, scientific, social, technical, and ethical-commonly found in the LHS literature. The proposed architectural framework is comprised of six decision layers that model these dimensions. The performance layer models goals, the scientific layer models the scientific dimension, the organizational layer models the social dimension, the data layer and information technology layer model the technical dimension, and the ethics and security layer models the ethical dimension. We describe the types of decisions that must be made within each layer and identify methods to support decision-making. In this paper, we outline

  15. Structural health monitoring (vibration) as a tool for identifying structural alterations of the lumbar spine

    DEFF Research Database (Denmark)

    Kawchuk, Gregory N; Hartvigsen, Jan; Edgecombe, Tiffany

    2016-01-01

    Structural health monitoring (SHM) is an engineering technique used to identify mechanical abnormalities not readily apparent through other means. Recently, SHM has been adapted for use in biological systems, but its invasive nature limits its clinical application. As such, the purpose of this pr......Structural health monitoring (SHM) is an engineering technique used to identify mechanical abnormalities not readily apparent through other means. Recently, SHM has been adapted for use in biological systems, but its invasive nature limits its clinical application. As such, the purpose...... of this project was to determine if a non-invasive form of SHM could identify structural alterations in the spines of living human subjects. Lumbar spines of 10 twin pairs were visualized by magnetic resonance imaging then assessed by a blinded radiologist to determine whether twin pairs were structurally...... concordant or discordant. Vibration was then applied to each subject's spine and the resulting response recorded from sensors overlying lumbar spinous processes. The peak frequency, area under the curve and the root mean square were computed from the frequency response function of each sensor. Statistical...

  16. A Review of the Piezoelectric Electromechanical Impedance Based Structural Health Monitoring Technique for Engineering Structures

    Directory of Open Access Journals (Sweden)

    Wongi S. Na

    2018-04-01

    Full Text Available The birth of smart materials such as piezoelectric (PZT transducers has aided in revolutionizing the field of structural health monitoring (SHM based on non-destructive testing (NDT methods. While a relatively new NDT method known as the electromechanical (EMI technique has been investigated for more than two decades, there are still various problems that must be solved before it is applied to real structures. The technique, which has a significant potential to contribute to the creation of one of the most effective SHM systems, involves the use of a single PZT for exciting and sensing of the host structure. In this paper, studies applied for the past decade related to the EMI technique have been reviewed to understand its trend. In addition, new concepts and ideas proposed by various authors are also surveyed, and the paper concludes with a discussion of the potential directions for future works.

  17. Impedance-based structural health monitoring of additive manufactured structures with embedded piezoelectric wafers

    Science.gov (United States)

    Scheyer, Austin G.; Anton, Steven R.

    2017-04-01

    Embedding sensors within additive manufactured (AM) structures gives the ability to develop smart structures that are capable of monitoring the mechanical health of a system. AM provides an opportunity to embed sensors within a structure during the manufacturing process. One major limitation of AM technology is the ability to verify the geometric and material properties of fabricated structures. Over the past several years, the electromechanical impedance (EMI) method for structural health monitoring (SHM) has been proven to be an effective method for sensing damage in structurers. The EMI method utilizes the coupling between the electrical and mechanical properties of a piezoelectric transducer to detect a change in the dynamic response of a structure. A piezoelectric device, usually a lead zirconate titanate (PZT) ceramic wafer, is bonded to a structure and the electrical impedance is measured across as range of frequencies. A change in the electrical impedance is directly correlated to changes made to the mechanical condition of the structure. In this work, the EMI method is employed on piezoelectric transducers embedded inside AM parts to evaluate the feasibility of performing SHM on parts fabricated using additive manufacturing. The fused deposition modeling (FDM) method is used to print specimens for this feasibility study. The specimens are printed from polylactic acid (PLA) in the shape of a beam with an embedded monolithic piezoelectric ceramic disc. The specimen is mounted as a cantilever while impedance measurements are taken using an HP 4194A impedance analyzer. Both destructive and nondestructive damage is simulated in the specimens by adding an end mass and drilling a hole near the free end of the cantilever, respectively. The Root Mean Square Deviation (RMSD) method is utilized as a metric for quantifying damage to the system. In an effort to determine a threshold for RMSD, the values are calculated for the variation associated with taking multiple

  18. A wireless laser displacement sensor node for structural health monitoring.

    Science.gov (United States)

    Park, Hyo Seon; Kim, Jong Moon; Choi, Se Woon; Kim, Yousok

    2013-09-30

    This study describes a wireless laser displacement sensor node that measures displacement as a representative damage index for structural health monitoring (SHM). The proposed measurement system consists of a laser displacement sensor (LDS) and a customized wireless sensor node. Wireless communication is enabled by a sensor node that consists of a sensor module, a code division multiple access (CDMA) communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless sensor node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.

  19. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  20. Historic Bim: a New Repository for Structural Health Monitoring

    Science.gov (United States)

    Banfi, F.; Barazzetti, L.; Previtali, M.; Roncoroni, F.

    2017-05-01

    Recent developments in Building Information Modelling (BIM) technologies are facilitating the management of historic complex structures using new applications. This paper proposes a generative method combining the morphological and typological aspects of the historic buildings (H-BIM), with a set of monitoring information. This combination of 3D digital survey, parametric modelling and monitoring datasets allows for the development of a system for archiving and visualizing structural health monitoring (SHM) data (Fig. 1). The availability of a BIM database allows one to integrate a different kind of data stored in different ways (e.g. reports, tables, graphs, etc.) with a representation directly connected to the 3D model of the structure with appropriate levels of detail (LoD). Data can be interactively accessed by selecting specific objects of the BIM, i.e. connecting the 3D position of the sensors installed with additional digital documentation. Such innovative BIM objects, which form a new BIM family for SHM, can be then reused in other projects, facilitating data archiving and exploitation of data acquired and processed. The application of advanced modeling techniques allows for the reduction of time and costs of the generation process, and support cooperation between different disciplines using a central workspace. However, it also reveals new challenges for parametric software and exchange formats. The case study presented is the medieval bridge Azzone Visconti in Lecco (Italy), in which multi-temporal vertical movements during load testing were integrated into H-BIM.

  1. HISTORIC BIM: A NEW REPOSITORY FOR STRUCTURAL HEALTH MONITORING

    Directory of Open Access Journals (Sweden)

    F. Banfi

    2017-05-01

    Full Text Available Recent developments in Building Information Modelling (BIM technologies are facilitating the management of historic complex structures using new applications. This paper proposes a generative method combining the morphological and typological aspects of the historic buildings (H-BIM, with a set of monitoring information. This combination of 3D digital survey, parametric modelling and monitoring datasets allows for the development of a system for archiving and visualizing structural health monitoring (SHM data (Fig. 1. The availability of a BIM database allows one to integrate a different kind of data stored in different ways (e.g. reports, tables, graphs, etc. with a representation directly connected to the 3D model of the structure with appropriate levels of detail (LoD. Data can be interactively accessed by selecting specific objects of the BIM, i.e. connecting the 3D position of the sensors installed with additional digital documentation. Such innovative BIM objects, which form a new BIM family for SHM, can be then reused in other projects, facilitating data archiving and exploitation of data acquired and processed. The application of advanced modeling techniques allows for the reduction of time and costs of the generation process, and support cooperation between different disciplines using a central workspace. However, it also reveals new challenges for parametric software and exchange formats. The case study presented is the medieval bridge Azzone Visconti in Lecco (Italy, in which multi-temporal vertical movements during load testing were integrated into H-BIM.

  2. Structural Health Monitoring for a Z-Type Special Vehicle

    Directory of Open Access Journals (Sweden)

    Chaolin Yuan

    2017-06-01

    Full Text Available Nowadays there exist various kinds of special vehicles designed for some purposes, which are different from regular vehicles in overall dimension and design. In that case, accidents such as overturning will lead to large economical loss and casualties. There are still no technical specifications to follow to ensure the safe operation and driving of these special vehicles. Owing to the poor efficiency of regular maintenance, it is more feasible and effective to apply real-time monitoring during the operation and driving process. In this paper, the fiber Bragg grating (FBG sensors are used to monitor the safety of a z-type special vehicle. Based on the structural features and force distribution, a reasonable structural health monitoring (SHM scheme is presented. Comparing the monitoring results with the finite element simulation results guarantees the accuracy and reliability of the monitoring results. Large amounts of data are collected during the operation and driving progress to evaluate the structural safety condition and provide reference for SHM systems developed for other special vehicles.

  3. A Wireless Laser Displacement Sensor Node for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Se Woon Choi

    2013-09-01

    Full Text Available This study describes a wireless laser displacement sensor node that measures displacement as a representative damage index for structural health monitoring (SHM. The proposed measurement system consists of a laser displacement sensor (LDS and a customized wireless sensor node. Wireless communication is enabled by a sensor node that consists of a sensor module, a code division multiple access (CDMA communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless sensor node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.

  4. Reframing measurement for structural health monitoring: a full-field strategy for structural identification

    Science.gov (United States)

    Dizaji, Mehrdad S.; Harris, Devin K.; Alipour, Mohamad; Ozbulut, Osman E.

    2018-03-01

    Structural health monitoring (SHM) describes a decision-making framework that is fundamentally guided by state change detection of structural systems. This framework typically relies on the use of continuous or semi-continuous monitoring of measured response to quantify this state change in structural system behavior, which is often related to the initiation of some form of damage. Measurement approaches used for traditional SHM are numerous, but most are limited to either describing localized or global phenomena, making it challenging to characterize operational structural systems which exhibit both. In addition to these limitations in sensing, SHM has also suffered from the inherent robustness inherent to most full-scale structural systems, making it challenging to identify local damage. These challenges highlight the opportunity for alternative strategies for SHM, strategies that are able to provide data suitable to translate into rich information. This paper describes preliminary results from a refined structural identification (St-ID) approach using fullfield measurements derived from high-speed 3D Digital Image Correlation (HSDIC) to characterize uncertain parameters (i.e. boundary and constitutive properties) of a laboratory scale structural component. The St-ID approach builds from prior work by supplementing full-field deflection and strain response with vibration response derived from HSDIC. Inclusion of the modal characteristics within a hybrid-genetic algorithm optimization scheme allowed for simultaneous integration of mechanical and modal response, thus enabling a more robust St-ID strategy than could be achieved with traditional sensing techniques. The use of full-field data is shown to provide a more comprehensive representation of the global and local behavior, which in turn increases the robustness of the St-Id framework. This work serves as the foundation for a new paradigm in SHM that emphasizes characterizing structural performance using a

  5. Automatic Sensor-Fault Detection System for Comprehensive Structural Health Monitoring System

    National Research Council Canada - National Science Library

    Chan, Hian-Leng; Zhang, Chang; Qing, Peter X; Ooi, Teng K; Marotta, Steve A

    2005-01-01

    Structural health monitoring systems are viewed as viable means to reduce life-cycle costs, increase structural reliability, and extend the operational hours for a wide variety of composite structures...

  6. Synergistic combination of systems for structural health monitoring and earthquake early warning for structural health prognosis and diagnosis

    Science.gov (United States)

    Wu, Stephen; Beck, James L.

    2012-04-01

    Earthquake early warning (EEW) systems are currently operating nationwide in Japan and are in beta-testing in California. Such a system detects an earthquake initiation using online signals from a seismic sensor network and broadcasts a warning of the predicted location and magnitude a few seconds to a minute or so before an earthquake hits a site. Such a system can be used synergistically with installed structural health monitoring (SHM) systems to enhance pre-event prognosis and post-event diagnosis of structural health. For pre-event prognosis, the EEW system information can be used to make probabilistic predictions of the anticipated damage to a structure using seismic loss estimation methodologies from performance-based earthquake engineering. These predictions can support decision-making regarding the activation of appropriate mitigation systems, such as stopping traffic from entering a bridge that has a predicted high probability of damage. Since the time between warning and arrival of the strong shaking is very short, probabilistic predictions must be rapidly calculated and the decision making automated for the mitigation actions. For post-event diagnosis, the SHM sensor data can be used in Bayesian updating of the probabilistic damage predictions with the EEW predictions as a prior. Appropriate Bayesian methods for SHM have been published. In this paper, we use pre-trained surrogate models (or emulators) based on machine learning methods to make fast damage and loss predictions that are then used in a cost-benefit decision framework for activation of a mitigation measure. A simple illustrative example of an infrastructure application is presented.

  7. Long-Term Structural Health Monitoring System for a High-Speed Railway Bridge Structure

    Science.gov (United States)

    Wu, Lai-Yi

    2015-01-01

    Nanjing Dashengguan Bridge, which serves as the shared corridor crossing Yangtze River for both Beijing-Shanghai high-speed railway and Shanghai-Wuhan-Chengdu railway, is the first 6-track high-speed railway bridge with the longest span throughout the world. In order to ensure safety and detect the performance deterioration during the long-time service of the bridge, a Structural Health Monitoring (SHM) system has been implemented on this bridge by the application of modern techniques in sensing, testing, computing, and network communication. The SHM system includes various sensors as well as corresponding data acquisition and transmission equipment for automatic data collection. Furthermore, an evaluation system of structural safety has been developed for the real-time condition assessment of this bridge. The mathematical correlation models describing the overall structural behavior of the bridge can be obtained with the support of the health monitoring system, which includes cross-correlation models for accelerations, correlation models between temperature and static strains of steel truss arch, and correlation models between temperature and longitudinal displacements of piers. Some evaluation results using the mean value control chart based on mathematical correlation models are presented in this paper to show the effectiveness of this SHM system in detecting the bridge's abnormal behaviors under the varying environmental conditions such as high-speed trains and environmental temperature. PMID:26451387

  8. Long-Term Structural Health Monitoring System for a High-Speed Railway Bridge Structure

    Directory of Open Access Journals (Sweden)

    You-Liang Ding

    2015-01-01

    Full Text Available Nanjing Dashengguan Bridge, which serves as the shared corridor crossing Yangtze River for both Beijing-Shanghai high-speed railway and Shanghai-Wuhan-Chengdu railway, is the first 6-track high-speed railway bridge with the longest span throughout the world. In order to ensure safety and detect the performance deterioration during the long-time service of the bridge, a Structural Health Monitoring (SHM system has been implemented on this bridge by the application of modern techniques in sensing, testing, computing, and network communication. The SHM system includes various sensors as well as corresponding data acquisition and transmission equipment for automatic data collection. Furthermore, an evaluation system of structural safety has been developed for the real-time condition assessment of this bridge. The mathematical correlation models describing the overall structural behavior of the bridge can be obtained with the support of the health monitoring system, which includes cross-correlation models for accelerations, correlation models between temperature and static strains of steel truss arch, and correlation models between temperature and longitudinal displacements of piers. Some evaluation results using the mean value control chart based on mathematical correlation models are presented in this paper to show the effectiveness of this SHM system in detecting the bridge’s abnormal behaviors under the varying environmental conditions such as high-speed trains and environmental temperature.

  9. Guided wave based structural health monitoring: A review

    International Nuclear Information System (INIS)

    Mitra, Mira; Gopalakrishnan, S

    2016-01-01

    The paper provides a state of the art review of guided wave based structural health monitoring (SHM). First, the fundamental concepts of guided wave propagation and its implementation for SHM is explained. Following sections present the different modeling schemes adopted, developments in the area of transducers for generation, and sensing of wave, signal processing and imaging technique, statistical and machine learning schemes for feature extraction. Next, a section is presented on the recent advancements in nonlinear guided wave for SHM. This is followed by section on Rayleigh and SH waves. Next is a section on real-life implementation of guided wave for industrial problems. The paper, though briefly talks about the early development for completeness, is primarily focussed on the recent progress made in the last decade. The paper ends by discussing and highlighting the future directions and open areas of research in guided wave based SHM. (topical review)

  10. Wake-up transceivers for structural health monitoring of bridges

    Science.gov (United States)

    Kumberg, T.; Kokert, J.; Younesi, V.; Koenig, S.; Reindl, L. M.

    2016-04-01

    In this article we present a wireless sensor network to monitor the structural health of a large-scale highway bridge in Germany. The wireless sensor network consists of several sensor nodes that use wake-up receivers to realize latency free and low-power communication. The sensor nodes are either equipped with very accurate tilt sensor developed by Northrop Grumman LITEF GmbH or with a Novatel OEM615 GNSS receiver. Relay nodes are required to forward measurement data to a base station located on the bridge. The base station is a gateway that transmits the local measurement data to a remote server where it can be further analyzed and processed. Further on, we present an energy harvesting system to supply the energy demanding GNSS sensor nodes to realize long term monitoring.

  11. Inspection of Piezoceramic Transducers Used for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Inka Mueller

    2017-01-01

    Full Text Available The use of piezoelectric wafer active sensors (PWAS for structural health monitoring (SHM purposes is state of the art for acousto-ultrasonic-based methods. For system reliability, detailed information about the PWAS itself is necessary. This paper gives an overview on frequent PWAS faults and presents the effects of these faults on the wave propagation, used for active acousto-ultrasonics-based SHM. The analysis of the wave field is based on velocity measurements using a laser Doppler vibrometer (LDV. New and established methods of PWAS inspection are explained in detail, listing advantages and disadvantages. The electro-mechanical impedance spectrum as basis for these methods is discussed for different sensor faults. This way this contribution focuses on a detailed analysis of PWAS and the need of their inspection for an increased reliability of SHM systems.

  12. Printing of microstructure strain sensor for structural health monitoring

    Science.gov (United States)

    Le, Minh Quyen; Ganet, Florent; Audigier, David; Capsal, Jean-Fabien; Cottinet, Pierre-Jean

    2017-05-01

    Recent advances in microelectronics and materials should allow the development of integrated sensors with transduction properties compatible with being printed directly onto a 3D substrate, especially metallic and polymer substrates. Inorganic and organic electronic materials in microstructured and nanostructured forms, intimately integrated in ink, offer particularly attractive characteristics, with realistic pathways to sophisticated embodiments. Here, we report on these strategies and demonstrate the potential of 3D-printed microelectronics based on a structural health monitoring (SHM) application for the precision weapon systems. We show that our printed sensors can be employed in non-invasive, high-fidelity and continuous strain monitoring of handguns, making it possible to implement printed sensors on a 3D substrate in either SHM or remote diagnostics. We propose routes to commercialization and novel device opportunities and highlight the remaining challenges for research.

  13. Rate-based structural health monitoring using permanently installed sensors

    Science.gov (United States)

    Corcoran, Joseph

    2017-09-01

    Permanently installed sensors are becoming increasingly ubiquitous, facilitating very frequent in situ measurements and consequently improved monitoring of `trends' in the observed system behaviour. It is proposed that this newly available data may be used to provide prior warning and forecasting of critical events, particularly system failure. Numerous damage mechanisms are examples of positive feedback; they are `self-accelerating' with an increasing rate of damage towards failure. The positive feedback leads to a common time-response behaviour which may be described by an empirical relation allowing prediction of the time to criticality. This study focuses on Structural Health Monitoring of engineering components; failure times are projected well in advance of failure for fatigue, creep crack growth and volumetric creep damage experiments. The proposed methodology provides a widely applicable framework for using newly available near-continuous data from permanently installed sensors to predict time until failure in a range of application areas including engineering, geophysics and medicine.

  14. Scavenger Receptor Structure and Function in Health and Disease

    Directory of Open Access Journals (Sweden)

    Izma Abdul Zani

    2015-05-01

    Full Text Available Scavenger receptors (SRs are a ‘superfamily’ of membrane-bound receptors that were initially thought to bind and internalize modified low-density lipoprotein (LDL, though it is currently known to bind to a variety of ligands including endogenous proteins and pathogens. New family of SRs and their properties have been identified in recent years, and have now been classified into 10 eukaryote families, defined as Classes A-J. These receptors are classified according to their sequences, although in each class they are further classified based in the variations of the sequence. Their ability to bind a range of ligands is reflected on the biological functions such as clearance of modified lipoproteins and pathogens. SR members regulate pathophysiological states including atherosclerosis, pathogen infections, immune surveillance, and cancer. Here, we review our current understanding of SR structure and function implicated in health and disease.

  15. Receptor tyrosine kinase structure and function in health and disease

    Directory of Open Access Journals (Sweden)

    Oleg A. Karpov

    2015-09-01

    Full Text Available Receptor tyrosine kinases (RTKs are membrane proteins that control the flow of information through signal transduction pathways, impacting on different aspects of cell function. RTKs are characterized by a ligand-binding ectodomain, a single transmembrane α-helix, a cytosolic region comprising juxtamembrane and kinase domains followed by a flexible C-terminal tail. Somatic and germline RTK mutations can induce aberrant signal transduction to give rise to cardiovascular, developmental and oncogenic abnormalities. RTK overexpression occurs in certain cancers, correlating signal strength and disease incidence. Diverse RTK activation and signal transduction mechanisms are employed by cells during commitment to health or disease. Small molecule inhibitors are one means to target RTK function in disease initiation and progression. This review considers RTK structure, activation, and signal transduction and evaluates biological relevance to therapeutics and clinical outcomes.

  16. Phase Space Dissimilarity Measures for Structural Health Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bubacz, Jacob A [ORNL; Chmielewski, Hana T [ORNL; Pape, Alexander E [ORNL; Depersio, Andrew J [ORNL; Hively, Lee M [ORNL; Abercrombie, Robert K [ORNL; Boone, Shane [ORNL

    2011-11-01

    A novel method for structural health monitoring (SHM), known as the Phase Space Dissimilarity Measures (PSDM) approach, is proposed and developed. The patented PSDM approach has already been developed and demonstrated for a variety of equipment and biomedical applications. Here, we investigate SHM of bridges via analysis of time serial accelerometer measurements. This work has four aspects. The first is algorithm scalability, which was found to scale linearly from one processing core to four cores. Second, the same data are analyzed to determine how the use of the PSDM approach affects sensor placement. We found that a relatively low-density placement sufficiently captures the dynamics of the structure. Third, the same data are analyzed by unique combinations of accelerometer axes (vertical, longitudinal, and lateral with respect to the bridge) to determine how the choice of axes affects the analysis. The vertical axis is found to provide satisfactory SHM data. Fourth, statistical methods were investigated to validate the PSDM approach for this application, yielding statistically significant results.

  17. Active Wireless System for Structural Health Monitoring Applications.

    Science.gov (United States)

    Perera, Ricardo; Pérez, Alberto; García-Diéguez, Marta; Zapico-Valle, José Luis

    2017-12-11

    The use of wireless sensors in Structural Health Monitoring (SHM) has increased significantly in the last years. Piezoelectric-based lead zirconium titanate (PZT) sensors have been on the rise in SHM due to their superior sensing abilities. They are applicable in different technologies such as electromechanical impedance (EMI)-based SHM. This work develops a flexible wireless smart sensor (WSS) framework based on the EMI method using active sensors for full-scale and autonomous SHM. In contrast to passive sensors, the self-sensing properties of the PZTs allow interrogating with or exciting a structure when desired. The system integrates the necessary software and hardware within a service-oriented architecture approach able to provide in a modular way the services suitable to satisfy the key requirements of a WSS. The framework developed in this work has been validated on different experimental applications. Initially, the reliability of the EMI method when carried out with the proposed wireless sensor system is evaluated by comparison with the wireless counterpart. Afterwards, the performance of the system is evaluated in terms of software stability and reliability of functioning.

  18. Active Wireless System for Structural Health Monitoring Applications

    Directory of Open Access Journals (Sweden)

    Ricardo Perera

    2017-12-01

    Full Text Available The use of wireless sensors in Structural Health Monitoring (SHM has increased significantly in the last years. Piezoelectric-based lead zirconium titanate (PZT sensors have been on the rise in SHM due to their superior sensing abilities. They are applicable in different technologies such as electromechanical impedance (EMI-based SHM. This work develops a flexible wireless smart sensor (WSS framework based on the EMI method using active sensors for full-scale and autonomous SHM. In contrast to passive sensors, the self-sensing properties of the PZTs allow interrogating with or exciting a structure when desired. The system integrates the necessary software and hardware within a service-oriented architecture approach able to provide in a modular way the services suitable to satisfy the key requirements of a WSS. The framework developed in this work has been validated on different experimental applications. Initially, the reliability of the EMI method when carried out with the proposed wireless sensor system is evaluated by comparison with the wireless counterpart. Afterwards, the performance of the system is evaluated in terms of software stability and reliability of functioning.

  19. Energy Harvesting for Aerospace Structural Health Monitoring Systems

    International Nuclear Information System (INIS)

    Pearson, M R; Eaton, M J; Pullin, R; Featherston, C A; Holford, K M

    2012-01-01

    Recent research into damage detection methodologies, embedded sensors, wireless data transmission and energy harvesting in aerospace environments has meant that autonomous structural health monitoring (SHM) systems are becoming a real possibility. The most promising system would utilise wireless sensor nodes that are able to make decisions on damage and communicate this wirelessly to a central base station. Although such a system shows great potential and both passive and active monitoring techniques exist for detecting damage in structures, powering such wireless sensors nodes poses a problem. Two such energy sources that could be harvested in abundance on an aircraft are vibration and thermal gradients. Piezoelectric transducers mounted to the surface of a structure can be utilised to generate power from a dynamic strain whilst thermoelectric generators (TEG) can be used to generate power from thermal gradients. This paper reports on the viability of these two energy sources for powering a wireless SHM system from vibrations ranging from 20 to 400Hz and thermal gradients up to 50°C. Investigations showed that using a single vibrational energy harvester raw power levels of up to 1mW could be generated. Further numerical modelling demonstrated that by optimising the position and orientation of the vibrational harvester greater levels of power could be achieved. However using commercial TEGs average power levels over a flight period between 5 to 30mW could be generated. Both of these energy harvesting techniques show a great potential in powering current wireless SHM systems where depending on the complexity the power requirements range from 1 to 180mW.

  20. Structural Health Management of Damaged Aircraft Structures Using the Digital Twin Concept

    Science.gov (United States)

    Seshadri, Banavara R.; Krishnamurthy, Thiagarajan

    2017-01-01

    The development of multidisciplinary integrated Structural Health Management (SHM) tools will enable accurate detection, and prognosis of damaged aircraft under normal and adverse conditions during flight. As part of the digital twin concept, methodologies are developed by using integrated multiphysics models, sensor information and input data from an in-service vehicle to mirror and predict the life of its corresponding physical twin. SHM tools are necessary for both damage diagnostics and prognostics for continued safe operation of damaged aircraft structures. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and structural damage conditions. A major concern in these structures is the growth of undetected damage/cracks due to fatigue and low velocity foreign object impact that can reach a critical size during flight, resulting in loss of control of the aircraft. To avoid unstable, catastrophic propagation of damage during a flight, load levels must be maintained that are below a reduced load-carrying capacity for continued safe operation of an aircraft. Hence, a capability is needed for accurate real-time predictions of damage size and safe load carrying capacity for structures with complex damage configurations. In the present work, a procedure is developed that uses guided wave responses to interrogate damage. As the guided wave interacts with damage, the signal attenuates in some directions and reflects in others. This results in a difference in signal magnitude as well as phase shifts between signal responses for damaged and undamaged structures. Accurate estimation of damage size, location, and orientation is made by evaluating the cumulative signal responses at various pre-selected sensor locations using a genetic algorithm (GA) based optimization procedure. The damage size, location, and orientation is obtained by minimizing the difference between the reference responses and the

  1. An addressable conducting network for autonomic structural health management of composite structures

    International Nuclear Information System (INIS)

    Takahashi, Kosuke; Park, Jong Se; Thomas Hahn, H

    2010-01-01

    The electrical resistance change method (ERCM) has long been an area of interest as an in-service health monitoring system. To apply the ERCM to existing structures, a new concept, the addressable conducting network (ACN), is proposed for autonomic structural health management of graphite/polymer composites. The ACN consists of two sets of conducting lines normal to each other, where one set resides on the top surface of the laminate and the other on the bottom surface. Damage can be detected by monitoring the resistance change 'through the laminate thickness' between two lines. By using a thermally mendable polymer as the matrix, the same conducting lines can be used to supply the electric current needed for resistive heating, thereby allowing the detected damage to be healed. As shown experimentally, the electrical resistance change method using an ACN distinguishes between laminates made of properly and improperly cured prepreg as well as revealing damage generated during three-point bending tests. Finite element analysis was performed to examine the feasibility of the ACN and indicated that the damage can be easily located from the spatial distribution of resistance changes and that the damaged area can be locally heated by supplying a large amount of current to selected conducting lines

  2. An addressable conducting network for autonomic structural health management of composite structures

    Science.gov (United States)

    Takahashi, Kosuke; Park, Jong Se; Hahn, H. Thomas

    2010-10-01

    The electrical resistance change method (ERCM) has long been an area of interest as an in-service health monitoring system. To apply the ERCM to existing structures, a new concept, the addressable conducting network (ACN), is proposed for autonomic structural health management of graphite/polymer composites. The ACN consists of two sets of conducting lines normal to each other, where one set resides on the top surface of the laminate and the other on the bottom surface. Damage can be detected by monitoring the resistance change 'through the laminate thickness' between two lines. By using a thermally mendable polymer as the matrix, the same conducting lines can be used to supply the electric current needed for resistive heating, thereby allowing the detected damage to be healed. As shown experimentally, the electrical resistance change method using an ACN distinguishes between laminates made of properly and improperly cured prepreg as well as revealing damage generated during three-point bending tests. Finite element analysis was performed to examine the feasibility of the ACN and indicated that the damage can be easily located from the spatial distribution of resistance changes and that the damaged area can be locally heated by supplying a large amount of current to selected conducting lines.

  3. Vibration-Based Damage Diagnosis in a Laboratory Cable-Stayed Bridge Model via an RCP-ARX Model Based Method

    International Nuclear Information System (INIS)

    Michaelides, P G; Apostolellis, P G; Fassois, S D

    2011-01-01

    Vibration-based damage detection and identification in a laboratory cable-stayed bridge model is addressed under inherent, environmental, and experimental uncertainties. The problem is challenging as conventional stochastic methods face difficulties due to uncertainty underestimation. A novel method is formulated based on identified Random Coefficient Pooled ARX (RCP-ARX) representations of the dynamics and statistical hypothesis testing. The method benefits from the ability of RCP models in properly capturing uncertainty. Its effectiveness is demonstrated via a high number of experiments under a variety of damage scenarios.

  4. Vibration-Based Damage Diagnosis in a Laboratory Cable-Stayed Bridge Model via an RCP-ARX Model Based Method

    Energy Technology Data Exchange (ETDEWEB)

    Michaelides, P G; Apostolellis, P G; Fassois, S D, E-mail: mixail@mech.upatras.gr, E-mail: fassois@mech.upatras.gr [Laboratory for Stochastic Mechanical Systems and Automation (SMSA), Department of Mechanical and Aeronautical Engineering, University of Patras, GR 265 00 Patras (Greece)

    2011-07-19

    Vibration-based damage detection and identification in a laboratory cable-stayed bridge model is addressed under inherent, environmental, and experimental uncertainties. The problem is challenging as conventional stochastic methods face difficulties due to uncertainty underestimation. A novel method is formulated based on identified Random Coefficient Pooled ARX (RCP-ARX) representations of the dynamics and statistical hypothesis testing. The method benefits from the ability of RCP models in properly capturing uncertainty. Its effectiveness is demonstrated via a high number of experiments under a variety of damage scenarios.

  5. Development of a Wireless Unified-Maintenance System for the Structural Health Monitoring of Civil Structures.

    Science.gov (United States)

    Heo, Gwanghee; Son, Byungjik; Kim, Chunggil; Jeon, Seunggon; Jeon, Joonryong

    2018-05-09

    A disaster preventive structural health monitoring (SHM) system needs to be equipped with the following abilities: First, it should be able to simultaneously measure diverse types of data (e.g., displacement, velocity, acceleration, strain, load, temperature, humidity, etc.) for accurate diagnosis. Second, it also requires standalone power supply to guarantee its immediate response in crisis (e.g., sudden interruption of normal AC power in disaster situations). Furthermore, it should be capable of prompt processing and realtime wireless communication of a huge amount of data. Therefore, this study is aimed at developing a wireless unified-maintenance system (WUMS) that would satisfy all the requirements for a disaster preventive SHM system of civil structures. The WUMS is designed to measure diverse types of structural responses in realtime based on wireless communication, allowing users to selectively use WiFi RF band and finally working in standalone mode by means of the field-programmable gate array (FPGA) technology. To verify its performance, the following tests were performed: (i) A test to see how far communication is possible in open field, (ii) a test on a shaker to see how accurate responses are, (iii) a modal test on a bridge to see how exactly characteristic real-time dynamic responses are of structures. The test results proved that the WUMS was able to secure stable communication far up to nearly 800 m away by acquiring wireless responses in realtime accurately, when compared to the displacement and acceleration responses which were acquired through wired communication. The analysis of dynamic characteristics also showed that the wireless acceleration responses in real-time represented satisfactorily the dynamic properties of structures. Therefore, the WUMS is proved valid as a SHM, and its outstanding performance is also proven.

  6. Structural health and prognostics management for offshore wind turbines :

    Energy Technology Data Exchange (ETDEWEB)

    Myrent, Noah J.; Kusnick, Joshua F.; Barrett, Natalie C.; Adams, Douglas E.; Griffith, Daniel

    2013-04-01

    Operations and maintenance costs for offshore wind plants are significantly higher than the current costs for land-based (onshore) wind plants. One way to reduce these costs would be to implement a structural health and prognostic management (SHPM) system as part of a condition based maintenance paradigm with smart load management and utilize a state-based cost model to assess the economics associated with use of the SHPM system. To facilitate the development of such a system a multi-scale modeling approach developed in prior work is used to identify how the underlying physics of the system are affected by the presence of damage and faults, and how these changes manifest themselves in the operational response of a full turbine. This methodology was used to investigate two case studies: (1) the effects of rotor imbalance due to pitch error (aerodynamic imbalance) and mass imbalance and (2) disbond of the shear web; both on a 5-MW offshore wind turbine in the present report. Based on simulations of damage in the turbine model, the operational measurements that demonstrated the highest sensitivity to the damage/faults were the blade tip accelerations and local pitching moments for both imbalance and shear web disbond. The initial cost model provided a great deal of insight into the estimated savings in operations and maintenance costs due to the implementation of an effective SHPM system. The integration of the health monitoring information and O&M cost versus damage/fault severity information provides the initial steps to identify processes to reduce operations and maintenance costs for an offshore wind farm while increasing turbine availability, revenue, and overall profit.

  7. Structural health and prognostics management for offshore wind turbines :

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, Daniel; Resor, Brian Ray; White, Jonathan Randall; Paquette, Joshua A.; Yoder, Nathanael C.

    2012-12-01

    Operations and maintenance costs for offshore wind plants are expected to be significantly higher than the current costs for onshore plants. One way in which these costs may be able to be reduced is through the use of a structural health and prognostic management system as part of a condition based maintenance paradigm with smart load management. To facilitate the creation of such a system a multiscale modeling approach has been developed to identify how the underlying physics of the system are affected by the presence of damage and how these changes manifest themselves in the operational response of a full turbine. The developed methodology was used to investigate the effects of a candidate blade damage feature, a trailing edge disbond, on a 5-MW offshore wind turbine and the measurements that demonstrated the highest sensitivity to the damage were the local pitching moments around the disbond. The multiscale method demonstrated that these changes were caused by a local decrease in the blades torsional stiffness due to the disbond, which also resulted in changes in the blades local strain field. Full turbine simulations were also used to demonstrate that derating the turbine power by as little as 5% could extend the fatigue life of a blade by as much as a factor of 3. The integration of the health monitoring information, conceptual repair cost versus damage size information, and this load management methodology provides an initial roadmap for reducing operations and maintenance costs for offshore wind farms while increasing turbine availability and overall profit.

  8. Energy Harvesting for Structural Health Monitoring Sensor Networks

    Energy Technology Data Exchange (ETDEWEB)

    Park, G.; Farrar, C. R.; Todd, M. D.; Hodgkiss, T.; Rosing, T.

    2007-02-26

    This report has been developed based on information exchanges at a 2.5-day workshop on energy harvesting for embedded structural health monitoring (SHM) sensing systems that was held June 28-30, 2005, at Los Alamos National Laboratory. The workshop was hosted by the LANL/UCSD Engineering Institute (EI). This Institute is an education- and research-focused collaboration between Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD), Jacobs School of Engineering. A Statistical Pattern Recognition paradigm for SHM is first presented and the concept of energy harvesting for embedded sensing systems is addressed with respect to the data acquisition portion of this paradigm. Next, various existing and emerging sensing modalities used for SHM and their respective power requirements are summarized, followed by a discussion of SHM sensor network paradigms, power requirements for these networks and power optimization strategies. Various approaches to energy harvesting and energy storage are discussed and limitations associated with the current technology are addressed. This discussion also addresses current energy harvesting applications and system integration issues. The report concludes by defining some future research directions and possible technology demonstrations that are aimed at transitioning the concept of energy harvesting for embedded SHM sensing systems from laboratory research to field-deployed engineering prototypes.

  9. Simultaneous excitation system for efficient guided wave structural health monitoring

    Science.gov (United States)

    Hua, Jiadong; Michaels, Jennifer E.; Chen, Xin; Lin, Jing

    2017-10-01

    Many structural health monitoring systems utilize guided wave transducer arrays for defect detection and localization. Signals are usually acquired using the ;pitch-catch; method whereby each transducer is excited in turn and the response is received by the remaining transducers. When extensive signal averaging is performed, the data acquisition process can be quite time-consuming, especially for metallic components that require a low repetition rate to allow signals to die out. Such a long data acquisition time is particularly problematic if environmental and operational conditions are changing while data are being acquired. To reduce the total data acquisition time, proposed here is a methodology whereby multiple transmitters are simultaneously triggered, and each transmitter is driven with a unique excitation. The simultaneously transmitted waves are captured by one or more receivers, and their responses are processed by dispersion-compensated filtering to extract the response from each individual transmitter. The excitation sequences are constructed by concatenating a series of chirps whose start and stop frequencies are randomly selected from a specified range. The process is optimized using a Monte-Carlo approach to select sequences with impulse-like autocorrelations and relatively flat cross-correlations. The efficacy of the proposed methodology is evaluated by several metrics and is experimentally demonstrated with sparse array imaging of simulated damage.

  10. A Structural Model Decomposition Framework for Systems Health Management

    Science.gov (United States)

    Roychoudhury, Indranil; Daigle, Matthew J.; Bregon, Anibal; Pulido, Belamino

    2013-01-01

    Systems health management (SHM) is an important set of technologies aimed at increasing system safety and reliability by detecting, isolating, and identifying faults; and predicting when the system reaches end of life (EOL), so that appropriate fault mitigation and recovery actions can be taken. Model-based SHM approaches typically make use of global, monolithic system models for online analysis, which results in a loss of scalability and efficiency for large-scale systems. Improvement in scalability and efficiency can be achieved by decomposing the system model into smaller local submodels and operating on these submodels instead. In this paper, the global system model is analyzed offline and structurally decomposed into local submodels. We define a common model decomposition framework for extracting submodels from the global model. This framework is then used to develop algorithms for solving model decomposition problems for the design of three separate SHM technologies, namely, estimation (which is useful for fault detection and identification), fault isolation, and EOL prediction. We solve these model decomposition problems using a three-tank system as a case study.

  11. Structural health monitoring and probability of detection estimation

    Science.gov (United States)

    Forsyth, David S.

    2016-02-01

    Structural health monitoring (SHM) methods are often based on nondestructive testing (NDT) sensors and are often proposed as replacements for NDT to lower cost and/or improve reliability. In order to take advantage of SHM for life cycle management, it is necessary to determine the Probability of Detection (POD) of the SHM system just as for traditional NDT to ensure that the required level of safety is maintained. Many different possibilities exist for SHM systems, but one of the attractive features of SHM versus NDT is the ability to take measurements very simply after the SHM system is installed. Using a simple statistical model of POD, some authors have proposed that very high rates of SHM system data sampling can result in high effective POD even in situations where an individual test has low POD. In this paper, we discuss the theoretical basis for determining the effect of repeated inspections, and examine data from SHM experiments against this framework to show how the effective POD from multiple tests can be estimated.

  12. On-line Bayesian model updating for structural health monitoring

    Science.gov (United States)

    Rocchetta, Roberto; Broggi, Matteo; Huchet, Quentin; Patelli, Edoardo

    2018-03-01

    Fatigue induced cracks is a dangerous failure mechanism which affects mechanical components subject to alternating load cycles. System health monitoring should be adopted to identify cracks which can jeopardise the structure. Real-time damage detection may fail in the identification of the cracks due to different sources of uncertainty which have been poorly assessed or even fully neglected. In this paper, a novel efficient and robust procedure is used for the detection of cracks locations and lengths in mechanical components. A Bayesian model updating framework is employed, which allows accounting for relevant sources of uncertainty. The idea underpinning the approach is to identify the most probable crack consistent with the experimental measurements. To tackle the computational cost of the Bayesian approach an emulator is adopted for replacing the computationally costly Finite Element model. To improve the overall robustness of the procedure, different numerical likelihoods, measurement noises and imprecision in the value of model parameters are analysed and their effects quantified. The accuracy of the stochastic updating and the efficiency of the numerical procedure are discussed. An experimental aluminium frame and on a numerical model of a typical car suspension arm are used to demonstrate the applicability of the approach.

  13. A structural model decomposition framework for systems health management

    Science.gov (United States)

    Roychoudhury, I.; Daigle, M.; Bregon, A.; Pulido, B.

    Systems health management (SHM) is an important set of technologies aimed at increasing system safety and reliability by detecting, isolating, and identifying faults; and predicting when the system reaches end of life (EOL), so that appropriate fault mitigation and recovery actions can be taken. Model-based SHM approaches typically make use of global, monolithic system models for online analysis, which results in a loss of scalability and efficiency for large-scale systems. Improvement in scalability and efficiency can be achieved by decomposing the system model into smaller local submodels and operating on these submodels instead. In this paper, the global system model is analyzed offline and structurally decomposed into local submodels. We define a common model decomposition framework for extracting submodels from the global model. This framework is then used to develop algorithms for solving model decomposition problems for the design of three separate SHM technologies, namely, estimation (which is useful for fault detection and identification), fault isolation, and EOL prediction. We solve these model decomposition problems using a three-tank system as a case study.

  14. Public health education in South Asia: a basis for structuring a master degree course.

    Science.gov (United States)

    Karkee, Rajendra

    2014-01-01

    Countries in South Asian Association for Regional Cooperation (SAARC) lack enough public health workforces to address their poor public health situation. Recently, there have been efforts to develop capacity building in public health in these countries by producing competent public health workforce through public health institutes and schools. Considering the wide nature of public health, the public health education and curricula should be linked with skills, knowledge, and competencies needed for public health practice and professionalism. The 3 domains of public health practice and the 10 essential public health services provide an operational framework to explore this link between public health practice and public health education. This framework incorporates five core areas of public health education. A master degree course in public health can be structured by incorporating these core areas as basic and reinforcing one of these areas as an elective followed by a dissertation work.

  15. Africanizing the social determinants of health: embedded structural inequalities and current health outcomes in sub-Saharan Africa.

    Science.gov (United States)

    Ichoku, Hyacinth Eme; Mooney, Gavin; Ataguba, John Ele-Ojo

    2013-01-01

    There is a growing interest in health policy in the social determinants of health. This has increased the demand for a paradigm shift within the discipline of health economics from health care economics to health economics. While the former involves what is essentially a medical model that emphasizes the maximization of individual health outcomes and considers the social organization of the health system as merely instrumental, the latter emphasizes that health and its distribution result from political, social, economic, and cultural structures. The discipline of health economics needs to refocus its energy on the social determinants of health but, in doing so, must dig deeper into the reasons for structurally embedded inequalities that give rise to inequalities in health outcomes. Especially is this the case in Africa and other low- and middle-income regions. This article seeks to provide empirical evidence from sub-Saharan Africa, including Ghana and Nigeria, on why such inequalities exist, arguing that these are in large part a product of hangovers from historically entrenched institutions. It argues that there is a need for research in health economics to embrace the social determinants of health, especially inequality, and to move away from its current mono-cultural focus.

  16. [Reviewing the shared strategy health bill: further measures to meet the structural challenges of the health system].

    Science.gov (United States)

    Lombrail, Pierre

    2014-01-01

    This article reviews the draft health bill entitled "Federate health professionals around a shared strategy", currently submitted for consultation in the context of the national health strategy in France. This bill comprises innovative measures for prevention and health care in France. In particular, it is designed to develop, strengthen and structure the prevention sector, especially in children and young people. It is also designed to organize health care trajectories and acquire the necessary tools to promote their development. However, the bill sometimes presents limited ambitions in terms of objectives and means. In particular, the project comprises almost none of the necessary actions on the social determinants of health. Overall, the orientations of this bill represent a first major step towards a health policy in France beyond the field of health care. However, we must remain vigilant concerning application of these orientations in the process of elaboration of the bill and its related regulations, and implementation of the national health strategy.

  17. Flexible High Energy-Conversion Sensing Materials for Structural Health Monitoring, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The applicant is developing flexible highly-efficient piezoelectric materials for use in structural health monitoring (SHM) as contemplated in the solicitation...

  18. Structural Health Monitoring with Fiber Bragg Grating and Piezo Arrays, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — IFOS and its research institute collaborator, Washington State University (WSU), have demonstrated feasibility of a structural health monitoring (SHM) system for...

  19. Highly Reliable Structural Health Monitoring of Smart Composite Vanes for Jet Engine, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Fiber Optic Systems and Auburn University propose a Fiber Bragg Grating (FBG) integrated Structural Health Monitoring (SHM) sensor system capable of...

  20. An Ultrasonic Wireless Sensor Network for Data Communication and Structural Health Monitoring, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Typical Structural Health Monitoring (SHM) uses embedded ultrasonic transducers exclusively for non-destructive evaluation (NDE) purposes, whereas data transfer is...

  1. Data Analysis Algorithm Suitable for Structural Health Monitoring Based on Dust Network, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed project will attempt to develop a data analysis system for structural health monitoring on space structures. The data analysis software will be a key...

  2. Data Analysis Algorithm Suitable for Structural Health Monitoring Based on Dust Network, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed project will attempt to develop a data analysis system for structural health monitoring on space structures. The data analysis software will be a key...

  3. Compressive sensing based wireless sensor for structural health monitoring

    Science.gov (United States)

    Bao, Yuequan; Zou, Zilong; Li, Hui

    2014-03-01

    Data loss is a common problem for monitoring systems based on wireless sensors. Reliable communication protocols, which enhance communication reliability by repetitively transmitting unreceived packets, is one approach to tackle the problem of data loss. An alternative approach allows data loss to some extent and seeks to recover the lost data from an algorithmic point of view. Compressive sensing (CS) provides such a data loss recovery technique. This technique can be embedded into smart wireless sensors and effectively increases wireless communication reliability without retransmitting the data. The basic idea of CS-based approach is that, instead of transmitting the raw signal acquired by the sensor, a transformed signal that is generated by projecting the raw signal onto a random matrix, is transmitted. Some data loss may occur during the transmission of this transformed signal. However, according to the theory of CS, the raw signal can be effectively reconstructed from the received incomplete transformed signal given that the raw signal is compressible in some basis and the data loss ratio is low. This CS-based technique is implemented into the Imote2 smart sensor platform using the foundation of Illinois Structural Health Monitoring Project (ISHMP) Service Tool-suite. To overcome the constraints of limited onboard resources of wireless sensor nodes, a method called random demodulator (RD) is employed to provide memory and power efficient construction of the random sampling matrix. Adaptation of RD sampling matrix is made to accommodate data loss in wireless transmission and meet the objectives of the data recovery. The embedded program is tested in a series of sensing and communication experiments. Examples and parametric study are presented to demonstrate the applicability of the embedded program as well as to show the efficacy of CS-based data loss recovery for real wireless SHM systems.

  4. Structure of health-care dyad leadership: an organization's experience.

    Science.gov (United States)

    Saxena, Anurag; Davies, Maura; Philippon, Don

    2018-05-08

    Purpose This study aims to explore the structural aspects (roles, responsibilities and reporting) of dyad leadership in one health-care organization (HCO). Design/methodology/approach The perceptions of 32 leaders (17 physician leaders and 15 dyad co-leaders) in formal leadership positions (six first-level with formal authority limited to teams or divisions, 23 middle-level with wider departmental or program responsibility and three senior-level with institution-wide authority) were obtained through focus groups and surveys. In addition, five senior leaders were interviewed. Descriptive statistics was used for quantitative data, and qualitative data were analyzed for themes by coding and categorization. Findings There are a large number of shared responsibilities in the hybrid model, as most activities in HCOs bridge administrative and professional spheres. These span the leadership (e.g. global performance and quality improvement) and management (e.g. human resources, budgets and education delivery) domains. The individual responsibilities, except for staff and physician engagement are in the management domain (e.g. operations and patient care). Both partners are responsible for joint decision-making, projecting a united front and joint reporting through a quadrat format. The mutual relationship and joint accountability are key characteristics and are critical to addressing potential conflicts and contradictions and achieving coherence. Practical implications Clarity of role will assist development of standardized job descriptions and required competencies, recruitment and leadership development. Originality/value This is an original empirical study presenting an integrated view of dyad leaders and senior leadership, meaningful expansion of shared responsibilities including academic functions and developing mutual relationship and emphasizing the central role of stability generating management functions.

  5. Structural health monitoring for fatigue life prediction of orthotropic brdige decks

    NARCIS (Netherlands)

    Pijpers, R.J.M.; Pahlavan, P.L.; Paulissen, J.H.; Hakkesteegt, H.C.; Jansen, T.H.

    2013-01-01

    Infrastructure asset owners are more and more confronted with structures reaching the end of their structural life. Structural Health Monitoring (SHM) systems should provide up-to-date information about the actual condition, as well predict the structural life and required maintenance of the assets

  6. Opportunities and challenges for structural health monitoring of radioactive waste systems and structures

    Energy Technology Data Exchange (ETDEWEB)

    Giurgiutiu, Victor [University of South Carolina, Columbia, SC 29208 (United States); Mendez Torres, Adrian E. [Savannah River National Laboratory, Aiken, SC 29808 (United States)

    2013-07-01

    Radioactive waste systems and structures (RWSS) are safety-critical facilities in need of monitoring over prolonged periods of time. Structural health monitoring (SHM) is an emerging technology that aims at monitoring the state of a structure through the use of networks of permanently mounted sensors. SHM technologies have been developed primarily within the aerospace and civil engineering communities. This paper addresses the issue of transitioning the SHM concept to the monitoring of RWSS and evaluates the opportunities and challenges associated with this process. Guided wave SHM technologies utilizing structurally-mounted piezoelectric wafer active sensors (PWAS) have a wide range of applications based on both propagating-wave and standing-wave methodologies. Hence, opportunities exist for transitioning these SHM technologies into RWSS monitoring. However, there exist certain special operational conditions specific to RWSS such as: radiation field, caustic environments, marine environments, and chemical, mechanical and thermal stressors. In order to address the high discharge of used nuclear fuel (UNF) and the limited space in the storage pools the U.S. the Department of Energy (DOE) has adopted a 'Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste' (January 2013). This strategy endorses the key principles that underpin the Blue Ribbon Commission's on America's Nuclear Future recommendations to develop a sustainable program for deploying an integrated system capable of transporting, storing, and disposing of UNF and high-level radioactive waste from civilian nuclear power generation, defense, national security, and other activities. This will require research to develop monitoring, diagnosis, and prognosis tools that can aid to establish a strong technical basis for extended storage and transportation of UNF. Monitoring of such structures is critical for assuring the safety and security of the

  7. Structural looseness investigation in slow rotating permanent magnet generators

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Mijatovic, Nenad; Sweeney, Christian Walsted

    2016-01-01

    Structural looseness in electric machines is a condition influencing the alignment of the machine and thus the overall bearing health. In this work, assessment of the above mentioned failure mode is tested on a slow rotating (running speed equal to 0.7Hz) permanent magnet generator (PMG), while...... collecting vibration and current data in order to cross-reference the indications from the two monitoring techniques. It is found that electric signature analysis shows no response even when two hold down bolts are untightened, whereas the analysis results from the vibration data exhibit superior performance....... The vibration-based condition indicators with the best response are the stator slot pass frequency, which can be directly related to the cogging torque in PMGs, and the 4th electric frequency harmonic, whose amplitudes increase due to the overall lower structure damping coefficient under looseness...

  8. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    decreased to 73% in 2005. Hence it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution on children. International studies mainly suggest a negative relationship between non-nuclear family structure and child outcomes. There are two...... relation between family structure changes and children's outcomes. Children who have experienced family structure changes during childhood seem to have worse educational outcomes and a higher propensity to being hospitalized and convicted of a crime. The children in the dataset experience up to 13 family...... structure changes during childhood. More family structure changes implies worse outcomes and might actually be more important than the number of years a child has spent in a single parent household. The age at which the family structure change occurs also seems to be important at least for some outcomes....

  9. International observatory on mental health systems: structure and operation

    Directory of Open Access Journals (Sweden)

    Minas Harry

    2009-04-01

    Full Text Available Abstract Introduction Sustained cooperative action is required to improve the mental health of populations, particularly in low and middle-income countries where meagre mental health investment and insufficient human and other resources result in poorly performing mental health systems. The Observatory The International Observatory on Mental Health Systems is a mental health systems research, education and development network that will contribute to the development of high quality mental health systems in low and middle-income countries. The work of the Observatory will be done by mental health systems research, education and development groups that are located in and managed by collaborating organisations. These groups will be supported by the IOMHS Secretariat, the International IOMHS Steering Group and a Technical Reference Group. Summary The International Observatory on Mental Health Systems is: 1 the mental health systems research, education and development groups; 2 the IOMHS Steering Group; 3 the IOMHS Technical Reference Group; and 4 the IOMHS Secretariat. The work of the Observatory will depend on free and open collaboration, sharing of knowledge and skills, and governance arrangements that are inclusive and that put the needs and interests of people with mental illness and their families at the centre of decision-making. We welcome contact from individuals and institutions that wish to contribute to achieving the goals of the Observatory. Now is the time to make it happen where it matters, by turning scientific knowledge into effective action for people's health. (J.W. Lee, in his acceptance speech on his appointment as the Director-General of the World Health Organization 1.

  10. Nonlinear structural damage detection using support vector machines

    Science.gov (United States)

    Xiao, Li; Qu, Wenzhong

    2012-04-01

    An actual structure including connections and interfaces may exist nonlinear. Because of many complicated problems about nonlinear structural health monitoring (SHM), relatively little progress have been made in this aspect. Statistical pattern recognition techniques have been demonstrated to be competitive with other methods when applied to real engineering datasets. When a structure existing 'breathing' cracks that open and close under operational loading may cause a linear structural system to respond to its operational and environmental loads in a nonlinear manner nonlinear. In this paper, a vibration-based structural health monitoring when the structure exists cracks is investigated with autoregressive support vector machine (AR-SVM). Vibration experiments are carried out with a model frame. Time-series data in different cases such as: initial linear structure; linear structure with mass changed; nonlinear structure; nonlinear structure with mass changed are acquired.AR model of acceleration time-series is established, and different kernel function types and corresponding parameters are chosen and compared, which can more accurate, more effectively locate the damage. Different cases damaged states and different damage positions have been recognized successfully. AR-SVM method for the insufficient training samples is proved to be practical and efficient on structure nonlinear damage detection.

  11. structured operational research and training in the public health

    African Journals Online (AJOL)

    2016-10-01

    Oct 1, 2016 ... PUBLIC HEALTH SECTOR: THE KENYAN EXPERIENCE. Operational research is becoming an increasingly valuable tool to health programmes seeking to ... Odense, Denmark) or EpiInfo (4), and the third and last workshop focuses on manuscript writing and submission to an open access peer reviewed.

  12. Effects of Piezoelectric (PZT) Sensor Bonding and the Characteristics of the Host Structure on Impedance Based Structural Health Monitoring

    Science.gov (United States)

    Jalloh, Abdul

    2005-01-01

    This study was conducted to investigate the effects of certain factors on the impedance signal in structural health monitoring. These factors were: the quality of the bond between the sensor and the host structure, and the characteristics of the host structure, such as geometry, mass, and material properties. This work was carried out to answer a set of questions, related to these factors, that were developed by the project team. The project team was comprised of Dr. Doug Ramers and Dr. Abdul Jalloh of the Summer Faculty Fellowship Program, Mr. Arnaldo Colon- Perez, a student intern from the University of Puerto Rico of Turabo, and Mr. John Lassiter and Mr. Bob Engberg of the Structural and Dynamics Test Group at NASA Marshall Space Flight Center (MSFC). This study was based on a review of the literature on structural health monitoring to investigate the factors referred to above because there was not enough time to plan and conduct the appropriate tests at MSFC during the tenure of the Summer Faculty Fellowship Program project members. The surveyed literature documents works on structural health monitoring that were based on laboratory tests that were conducted using bolted trusses and other civil engineering type structures for the most part. These are not the typical types of structures used in designing and building NASA s space vehicles and systems. It was therefore recommended that tests be conducted using NASA type structures, such as pressure vessels, to validate the observations made in this report.

  13. Tunable Laser Development for In-flight Fiber Optic Based Structural Health Monitoring Systems

    Science.gov (United States)

    Richards, Lance; Parker, Allen; Chan, Patrick

    2014-01-01

    The objective of this task is to investigate, develop, and demonstrate a low-cost swept lasing light source for NASA DFRC's fiber optics sensing system (FOSS) to perform structural health monitoring on current and future aerospace vehicles. This is the regular update of the Tunable Laser Development for In-flight Fiber Optic Based Structural Health Monitoring Systems website.

  14. Italian regional health system structure and expected cancer survival.

    Science.gov (United States)

    Vercelli, Marina; Lillini, Roberto; Quaglia, Alberto; Capocaccia, Riccardo

    2014-01-01

    Few studies deal with the association of socioeconomic and health system resource variables with cancer survival at the Italian regional level, where the greatest number of decisions about social and health policies and resource allocations are taken. The present study aimed to describe the causal relationships between socioeconomic and health system resource factors and regional cancer survival and to compute the expected cancer survival at provincial, regional and area levels. Age-standardized relative survival at 5 years from diagnosis of cases incident in 1995-1998 and followed up to 2004 were derived by gender for 11 sites from the Italian Association of Cancer Registries data bank. The socioeconomic and health system resource variables, describing at a regional level the macro-economy, demography, labor market, and health resources for 1995-2005, came from the Health for All database. A principal components factor analysis was applied to the socioeconomic and health system resource variables. For every site, linear regression models were computed considering the relative survival at 5 years as a dependent variable and the principal components factor analysis factors as independent variables. The factors described the socioeconomic and health-related features of the regional systems and were causally related to the characteristics of the patient taken in charge. The models built by the factors allowed computation of the expected relative survival at 5 years with very good concordance with those observed at regional, macro-regional and national levels. In the regions without any cancer registry, survival was coherent with that of neighboring regions with similar socioeconomic and health system resources characteristics. The models highlighted the causal correlations between socioeconomic and health system resources and cancer survival, suggesting that they could be good evaluation tools for the efficiency of the resources allocation and use.

  15. Survey of social health insurance structure in selected countries; providing framework for basic health insurance in Iran.

    Science.gov (United States)

    Mohammadi, Effat; Raissi, Ahmad Reza; Barooni, Mohsen; Ferdoosi, Massoud; Nuhi, Mojtaba

    2014-01-01

    Health system reforms are the most strategic issue that has been seriously considered in healthcare systems in order to reduce costs and increase efficiency and effectiveness. The costs of health system finance in our country, lack of universal coverage in health insurance, and related issues necessitate reforms in our health system financing. The aim of this research was to prepare a structure of framework for social health insurance in Iran and conducting a comparative study in selected countries with social health insurance. This comparative descriptive study was conducted in three phases. The first phase of the study examined the structure of health social insurance in four countries - Germany, South Korea, Egypt, and Australia. The second phase was to develop an initial model, which was designed to determine the shared and distinguishing points of the investigated structures, for health insurance in Iran. The third phase was to validate the final research model. The developed model by the Delphi method was given to 20 professionals in financing of the health system, health economics and management of healthcare services. Their comments were collected in two stages and its validity was confirmed. The study of the structure of health insurance in the selected countries shows that health social insurance in different countries have different structures. Based on the findings of the present study, the current situation of the health system, and the conducted surveys, the following framework is suitable for the health social insurance system in Iran. The Health Social Insurance Organization has a unique service by having five funds of governmental employees, companies and NGOs, self-insured, villagers, and others, which serves as a nongovernmental organization under the supervision of public law and by decision- and policy-making of the Health Insurance Supreme Council. Membership in this organization is based on the nationality or residence, which the insured by

  16. A Structural Model Decomposition Framework for Systems Health Management

    Data.gov (United States)

    National Aeronautics and Space Administration — Systems health management (SHM) is an impor- tant set of technologies aimed at increasing system safety and reliability by detecting, isolating, and identifying...

  17. Semantic Interoperability in the Structured Electronic Health Record

    Czech Academy of Sciences Publication Activity Database

    Hanzlíček, Petr; Přečková, Petra; Zvárová, Jana

    -, č. 69 (2007), s. 52-53 ISSN 0926-4981 Institutional research plan: CEZ:AV0Z10300504 Keywords : electronic health record * terminology * classification Subject RIV: IN - Informatics, Computer Science

  18. Structural health monitoring of bridge cables : An overview

    OpenAIRE

    DRISSI HABTI, Monssef; BETTI, Raimondo; YANEV, Bojidar

    2009-01-01

    Bridges are critical components of the civil infrastructure and are normally designed for a long life span. The life span of suspension bridges depends on the health of their cables, which, in turn, is a function of many factors. Therefore, continuous health monitoring (SHM) and regular condition assessment of cables is highly desirable. In this article, some SHM procedures based on direct, indirect non-destructive techniques NDT, and vibration theory are presented.

  19. Applications of Piezoelectric Materials in Structural Health Monitoring and Repair: Selected Research Examples.

    Science.gov (United States)

    Duan, Wen Hui; Wang, Quan; Quek, Ser Tong

    2010-12-06

    The paper reviews the recent applications of piezoelectric materials in structural health monitoring and repair conducted by the authors. First, commonly used piezoelectric materials in structural health monitoring and structure repair are introduced. The analysis of plain piezoelectric sensors and actuators and interdigital transducer and their applications in beam, plate and pipe structures for damage detection are reviewed in detail. Second, an overview is presented on the recent advances in the applications of piezoelectric materials in structural repair. In addition, the basic principle and the current development of the technique are examined.

  20. Applications of Piezoelectric Materials in Structural Health Monitoring and Repair: Selected Research Examples

    Directory of Open Access Journals (Sweden)

    Ser Tong Quek

    2010-12-01

    Full Text Available The paper reviews the recent applications of piezoelectric materials in structural health monitoring and repair conducted by the authors. First, commonly used piezoelectric materials in structural health monitoring and structure repair are introduced. The analysis of plain piezoelectric sensors and actuators and interdigital transducer and their applications in beam, plate and pipe structures for damage detection are reviewed in detail. Second, an overview is presented on the recent advances in the applications of piezoelectric materials in structural repair. In addition, the basic principle and the current development of the technique are examined.

  1. Sibling Relationships and Adolescents' Mental Health: The Interrelationship of Structure and Quality

    Science.gov (United States)

    Yuan, Anastasia S. Vogt

    2009-01-01

    Although sibling structure influences some aspects of adolescents' well-being, including deviance and educational achievement, little research has explored the association between sibling structure and adolescents' mental health. This study explores how sibling structure (the number of siblings, full versus step- or half-siblings, the relative age…

  2. Humor: Power Conveying Social Structures Inside Forensic Mental Health Nursing.

    Science.gov (United States)

    Gildberg, Frederik A; Paaske, Kristian J; Rasmussen, Vivian L; Nissen, Ricko D; Bradley, Stephen K; Hounsgaard, Lise

    2016-01-01

    According to research literature, humor inside the staff-patient interaction seems to be significant in the area of forensic mental healthcare. However, existing literature on the subject is limited. Therefore, the aim of this study was to explore the characteristics of the use humor by forensic mental health staff members in interactions with forensic mental health inpatients. The study included 32 forensic mental health staff members, used 307 hours of participant observations, 48 informal interviews, and seven formal semistructured interviews. Outcomes identify four themes concerning the conveyance of power to, from, and between forensic mental health staff and patients as they interact: (a) "the informal use: the human-to-human approach," characterized by an informal use of humor and without any reference to mental health issues; (b) the "formal use of humor: the staff-patient approach," characterized as formal with a view on the patient as mentally ill, unable to understand humor, and with the aim of using humor to prevent conflicts or negative behavior; (c) "protest against requested care: the human-patient approach," characterized by the use of humor as a protest against requested care; and the use of (d) "inadequacy humor: the staff-human approach," characterized by the use of inadequacy-humor referring to, for example, patients' physical features. Recommendations and clinical implications are discussed.

  3. An online substructure identification method for local structural health monitoring

    International Nuclear Information System (INIS)

    Hou, Jilin; Ou, Jinping; Jankowski, Łukasz

    2013-01-01

    This paper proposes a substructure isolation method, which uses time series of measured local response for online monitoring of substructures. The proposed monitoring process consists of two key steps: construction of the isolated substructure, and its identification. The isolated substructure is an independent virtual structure, which is numerically isolated from the global structure by placing virtual supports on the interface. First, the isolated substructure is constructed by a specific linear combination of time series of its measured local responses. Then, the isolated substructure is identified using its local natural frequencies extracted from the combined responses. The substructure is assumed to be linear; the outside part of the global structure can have any characteristics. The method has no requirements on the initial state of the structure, and so the process can be carried out repetitively for online monitoring. Online isolation and monitoring is illustrated in a numerical example with a frame model, and then verified in a cantilever beam experiment. (paper)

  4. In Situ Guided Wave Structural Health Monitoring System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Corrosion and fatigue induced metal-loss and cracks are common problems for missiles and aircraft structures. A wide range of field conditions such as humidity,...

  5. Quantifiable and Reliable Structural Health Management Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Under Project Constellation, NASA is developing a new generation of spacecraft for human spaceflight. A significant percentage of the structures used in these...

  6. Integrating Structural Health Management with Contingency Control for Wind Turbines

    Directory of Open Access Journals (Sweden)

    Kai Goebel

    2013-01-01

    Full Text Available Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbine blades with contingency control to balance the trade-offs between maintaining system health and energy capture. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  7. PHIRE (Public Health Innovation and Research in Europe): methods, structures and evaluation.

    Science.gov (United States)

    Barnhoorn, Floris; McCarthy, Mark; Devillé, Walter; Alexanderson, Kristina; Voss, Margaretha; Conceição, Claudia

    2013-11-01

    Public Health Innovation and Research in Europe (PHIRE), building on previous European collaborative projects, was developed to assess national uptake and impacts of European public health innovations, to describe national public health research programmes, strategies and structures and to develop participation of researchers through the organizational structures of the European Public Health Association (EUPHA). This article describes the methods used. PHIRE was led by EUPHA with seven partner organisations over 30 months. It was conceived to engage the organisation of EUPHA--working through its thematic Sections, and through its national public health associations--and assess innovation and research across 30 European countries. Public health research was defined broadly as health research at population and organisational level. There were seven Work Packages (three covering coordination and four for technical aspects) led by partners and coordinated through management meetings. Seven EUPHA Sections identified eight innovations within the projects funded by the Public Health Programme of the European Commission Directorate for Health and Consumers. Country informants, identified through EUPHA thematic Sections, reported on national uptake of the innovations in eight public health projects supported by the European Union Public Health Programme. Four PHIRE partners, each taking a regional sector of Europe, worked with the public health associations and other informants to describe public health research programmes, calls and systems. A classification was created for the national public health research programmes and calls in 2010. The internal and external evaluations were supportive. PHIRE described public health innovations and research across Europe through national experts. More work is needed to conceptualize and define public health 'innovations' and to develop theories and methods for the assessment of their uptake and impacts at country and cross

  8. Health level seven interoperability strategy: big data, incrementally structured.

    Science.gov (United States)

    Dolin, R H; Rogers, B; Jaffe, C

    2015-01-01

    Describe how the HL7 Clinical Document Architecture (CDA), a foundational standard in US Meaningful Use, contributes to a "big data, incrementally structured" interoperability strategy, whereby data structured incrementally gets large amounts of data flowing faster. We present cases showing how this approach is leveraged for big data analysis. To support the assertion that semi-structured narrative in CDA format can be a useful adjunct in an overall big data analytic approach, we present two case studies. The first assesses an organization's ability to generate clinical quality reports using coded data alone vs. coded data supplemented by CDA narrative. The second leverages CDA to construct a network model for referral management, from which additional observations can be gleaned. The first case shows that coded data supplemented by CDA narrative resulted in significant variances in calculated performance scores. In the second case, we found that the constructed network model enables the identification of differences in patient characteristics among different referral work flows. The CDA approach goes after data indirectly, by focusing first on the flow of narrative, which is then incrementally structured. A quantitative assessment of whether this approach will lead to a greater flow of data and ultimately a greater flow of structured data vs. other approaches is planned as a future exercise. Along with growing adoption of CDA, we are now seeing the big data community explore the standard, particularly given its potential to supply analytic en- gines with volumes of data previously not possible.

  9. Addressing health inequalities by using Structural Funds. A question of opportunities.

    Science.gov (United States)

    Neagu, Oana Maria; Michelsen, Kai; Watson, Jonathan; Dowdeswell, Barrie; Brand, Helmut

    2017-03-01

    Making up a third of the EU budget, Structural and Investment Funds can provide important opportunities for investing in policies that tackle inequalities in health. This article looks back and forward at the 2007-2013 and 2014-2020 financial periods in an attempt to inform the development of health equity as a strand of policy intervention under regional development. It combines evidence from health projects funded through Structural Funds and a document analyses that locates interventions for health equity under the new regulations. The map of opportunities has changed considerably since the last programming period, creating more visibility for vulnerable groups, social determinants of health and health systems sustainability. As the current programming period is progressing, this paper contributes to maximizing this potential but also identifying challenges and implementation gaps for prospective health system engagement in pursuing health equity as part of Structural Funds projects. The austerity measures and their impact on public spending, building political support for investments as well as the difficulties around pursuing health gains as an objective of other policy areas are some of the challenges to overcome. European Structural and Investment Funds could be a window of opportunity that triggers engagement for health equity if sectors adopt a transformative approach and overcome barriers, cooperate for common goals and make better use of the availability of these resources. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. An Embedded Wireless Sensor Network with Wireless Power Transmission Capability for the Structural Health Monitoring of Reinforced Concrete Structures.

    Science.gov (United States)

    Gallucci, Luca; Menna, Costantino; Angrisani, Leopoldo; Asprone, Domenico; Moriello, Rosario Schiano Lo; Bonavolontà, Francesco; Fabbrocino, Francesco

    2017-11-07

    Maintenance strategies based on structural health monitoring can provide effective support in the optimization of scheduled repair of existing structures, thus enabling their lifetime to be extended. With specific regard to reinforced concrete (RC) structures, the state of the art seems to still be lacking an efficient and cost-effective technique capable of monitoring material properties continuously over the lifetime of a structure. Current solutions can typically only measure the required mechanical variables in an indirect, but economic, manner, or directly, but expensively. Moreover, most of the proposed solutions can only be implemented by means of manual activation, making the monitoring very inefficient and then poorly supported. This paper proposes a structural health monitoring system based on a wireless sensor network (WSN) that enables the automatic monitoring of a complete structure. The network includes wireless distributed sensors embedded in the structure itself, and follows the monitoring-based maintenance (MBM) approach, with its ABCDE paradigm, namely: accuracy, benefit, compactness, durability, and easiness of operations. The system is structured in a node level and has a network architecture that enables all the node data to converge in a central unit. Human control is completely unnecessary until the periodic evaluation of the collected data. Several tests are conducted in order to characterize the system from a metrological point of view and assess its performance and effectiveness in real RC conditions.

  11. An Embedded Wireless Sensor Network with Wireless Power Transmission Capability for the Structural Health Monitoring of Reinforced Concrete Structures

    Directory of Open Access Journals (Sweden)

    Luca Gallucci

    2017-11-01

    Full Text Available Maintenance strategies based on structural health monitoring can provide effective support in the optimization of scheduled repair of existing structures, thus enabling their lifetime to be extended. With specific regard to reinforced concrete (RC structures, the state of the art seems to still be lacking an efficient and cost-effective technique capable of monitoring material properties continuously over the lifetime of a structure. Current solutions can typically only measure the required mechanical variables in an indirect, but economic, manner, or directly, but expensively. Moreover, most of the proposed solutions can only be implemented by means of manual activation, making the monitoring very inefficient and then poorly supported. This paper proposes a structural health monitoring system based on a wireless sensor network (WSN that enables the automatic monitoring of a complete structure. The network includes wireless distributed sensors embedded in the structure itself, and follows the monitoring-based maintenance (MBM approach, with its ABCDE paradigm, namely: accuracy, benefit, compactness, durability, and easiness of operations. The system is structured in a node level and has a network architecture that enables all the node data to converge in a central unit. Human control is completely unnecessary until the periodic evaluation of the collected data. Several tests are conducted in order to characterize the system from a metrological point of view and assess its performance and effectiveness in real RC conditions.

  12. Mapping the Zambian prison health system: An analysis of key structural determinants.

    Science.gov (United States)

    Topp, Stephanie M; Moonga, Clement N; Luo, Nkandu; Kaingu, Michael; Chileshe, Chisela; Magwende, George; Henostroza, German

    2017-07-01

    Health and health service access in Zambian prisons are in a state of 'chronic emergency'. This study aimed to identify major structural barriers to strengthening the prison health systems. A case-based analysis drew on key informant interviews (n = 7), memos generated during workshops (n = 4) document review and investigator experience. Structural determinants were defined as national or macro-level contextual and material factors directly or indirectly influencing prison health services. The analysis revealed that despite an favourable legal framework, four major and intersecting structural factors undermined the Zambian prison health system. Lack of health financing was a central and underlying challenge. Weak health governance due to an undermanned prisons health directorate impeded planning, inter-sectoral coordination, and recruitment and retention of human resources for health. Outdated prison infrastructure simultaneously contributed to high rates of preventable disease related to overcrowding and lack of basic hygiene. These findings flag the need for policy and administrative reform to establish strong mechanisms for domestic prison health financing and enable proactive prison health governance, planning and coordination.

  13. Data-intensive structural health monitoring in the infrawatch project

    NARCIS (Netherlands)

    Veerman, R.P.; Miao, S.; Koenders, E.A.B.; Knobbe, A.

    2013-01-01

    The InfraWatch project is a Dutch research project, aimed at developing novel techniques for large-scale monitoring of concrete infra-structures. The project involves a large bridge, fitted with multiple types of sensors that capture the high-resolution dynamic behavior of the bridge. With 145

  14. Factor Structure of the WPPSI in Mental Health Clinic Settings.

    Science.gov (United States)

    Haynes, Jack P.; Atkinson, David

    1984-01-01

    Factor-analyzed the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) scores of emotionally disturbed children (N=181). The results suggested that the structure of intelligence for emotionally disturbed children is similar to that for normal children. WPPSI profile analysis that uses subtest scores may be invalid in clinical settings.…

  15. Maturation of Structural Health Management Systems for Solid Rocket Motors

    Science.gov (United States)

    Quing, Xinlin; Beard, Shawn; Zhang, Chang

    2011-01-01

    Concepts of an autonomous and automated space-compliant diagnostic system were developed for conditioned-based maintenance (CBM) of rocket motors for space exploration vehicles. The diagnostic system will provide real-time information on the integrity of critical structures on launch vehicles, improve their performance, and greatly increase crew safety while decreasing inspection costs. Using the SMART Layer technology as a basis, detailed procedures and calibration techniques for implementation of the diagnostic system were developed. The diagnostic system is a distributed system, which consists of a sensor network, local data loggers, and a host central processor. The system detects external impact to the structure. The major functions of the system include an estimate of impact location, estimate of impact force at impacted location, and estimate of the structure damage at impacted location. This system consists of a large-area sensor network, dedicated multiple local data loggers with signal processing and data analysis software to allow for real-time, in situ monitoring, and longterm tracking of structural integrity of solid rocket motors. Specifically, the system could provide easy installation of large sensor networks, onboard operation under harsh environments and loading, inspection of inaccessible areas without disassembly, detection of impact events and impact damage in real-time, and monitoring of a large area with local data processing to reduce wiring.

  16. Recent Research and Application Activities on Structural Health ...

    African Journals Online (AJOL)

    ... newly constructed bridges, (2) research and development activities on smart sensors such as optical fiber sensors and piezo-electric sensors, (3) structural damage detection methods using measured data, and (4) a test road project for pavement design verification and enhancement by the Korea Highway Corporation.

  17. Structural and contextual dimensions of Iranian primary health care system at local level.

    Science.gov (United States)

    Zanganeh Baygi, Mehdi; Seyedin, Hesam; Salehi, Masoud; Jafari Sirizi, Mehdi

    2015-01-01

    In recent years, family physician plan was established as the main strategy of health system in Iran, while organizational structure of the primary health care system has remained the same as thirty years ago. This study was performed to illustrate structural and contextual dimensions of organizational structure and relationship between them in Iranian primary health care system at local level. A cross-sectional quantitative study was conducted from January to June 2013, during which 121 questionnaires were distributed among senior and junior managers of city health centers at Medical Sciences universities in Iran. Validity of the questionnaire was confirmed by experts (CVI = 0.089 and CVR more than 0.85) and Cronbach α was utilized for reliability (α = 0.904). We used multistage sampling method in this study and analysis of the data was performed by SPSS software using different tests. Local level of primary health care system in Iran had mechanical structure, but in contextual dimensions the results showed different types. There was a significant relationship between structural and contextual dimensions (r = 0.642, P value structural dimensions. Because of the changes in goals and strategies of Iranian health system in recent years, it is urgently recommended to reform the current structure to increase efficiency and effectiveness of the system.

  18. Applications in bridge structure health monitoring using distributed fiber sensing

    Science.gov (United States)

    Feng, Yafei; Zheng, Huan; Ge, Huiliang

    2017-10-01

    In this paper, Brillouin Optical Time Domain Analysis (BOTDA) is proposed to solve the problem that the traditional point sensor is difficult to realize the comprehensive safety monitoring of bridges and so on. This technology not only breaks through the bottleneck of traditional monitoring point sensor, realize the distributed measurement of temperature and strain on a transmission path; can also be used for bridge and other structures of the damage identification, fracture positioning, settlement monitoring. The effectiveness and frontier of the technology are proved by comparing the test of the indoor model beam and the external field bridge, and the significance of the distributed optical fiber sensing technology to the monitoring of the important structure of the bridge is fully explained.

  19. Structural health monitoring in composite materials using frequency response methods

    Science.gov (United States)

    Kessler, Seth S.; Spearing, S. Mark; Atalla, Mauro J.; Cesnik, Carlos E. S.; Soutis, Constantinos

    2001-08-01

    Cost effective and reliable damage detection is critical for the utilization of composite materials in structural applications. Non-destructive evaluation techniques (e.g. ultrasound, radiography, infra-red imaging) are available for use during standard repair and maintenance cycles, however by comparison to the techniques used for metals these are relatively expensive and time consuming. This paper presents part of an experimental and analytical survey of candidate methods for the detection of damage in composite materials. The experimental results are presented for the application of modal analysis techniques applied to rectangular laminated graphite/epoxy specimens containing representative damage modes, including delamination, transverse ply cracks and through-holes. Changes in natural frequencies and modes were then found using a scanning laser vibrometer, and 2-D finite element models were created for comparison with the experimental results. The models accurately predicted the response of the specimems at low frequencies, but the local excitation and coalescence of higher frequency modes make mode-dependent damage detection difficult and most likely impractical for structural applications. The frequency response method was found to be reliable for detecting even small amounts of damage in a simple composite structure, however the potentially important information about damage type, size, location and orientation were lost using this method since several combinations of these variables can yield identical response signatures.

  20. Structure of Primary Health Care: Lessons from a Rural Area in ...

    African Journals Online (AJOL)

    Structure of Primary Health Care: Lessons from a Rural Area in South-West Nigeria. ... of the facilities enjoyed community participation in planning and management. There ... None of the facilities had a functional 2-way referral system in place.

  1. Real-Time Probabilistic Structural Health Management Using Machine Learning and GPU Computing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project seeks to deliver an ultra-efficient, high-fidelity structural health management (SHM) framework using machine learning and graphics processing...

  2. Time Reversal Acoustic Structural Health Monitoring Using Array of Embedded Sensors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Time Reversal Acoustic (TRA) structural health monitoring with an embedded sensor array represents a new approach to in-situ nondestructive evaluation of air-space...

  3. Adoption of Smart Structures for Prevention of Health Hazards in Buildings

    Science.gov (United States)

    Oke, Ayodeji; Aigbavboa, Clinton; Ngema, Wiseman

    2017-11-01

    The importance of building quality to the health and well-being of occupants and surrounding neighbors cannot be overemphasized. Smart structures were construed to proffer solution to various issues of sustainable development including social factors that is concerned with health and safety of people. Based on existing literature materials on building quality, smart structures and general aspect of sustainable developments, this study examined the benefits of smart structures in the prevention of various health issues in infrastructural buildings, which has been a concern for stakeholders in the architecture, engineering and construction industry. The criterion for indoor environmental quality was adopted and various health and bodily issues related to building quality were explained. The adoption of smart structure concept will help to manage physical, chemical, biological and psychological factors of building with a view to enhancing better quality of life of occupants.

  4. A pilot study on diagnostic sensor networks for structure health monitoring.

    Science.gov (United States)

    2013-08-01

    The proposal was submitted in an effort to obtain some preliminary results on using sensor networks for real-time structure health : monitoring. The proposed work has twofold: to develop and validate an elective algorithm for the diagnosis of coupled...

  5. Passive Wireless Sensor System for Space and Structural Health Monitoring, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Aviana Molecular (Aviana) and the University of Central Florida (UCF) propose to develop a Passive Wireless Sensor System (PWSS) for Structural Health Monitoring...

  6. Low cost structural health monitoring of bridges using wireless sensors : research summary.

    Science.gov (United States)

    2012-05-01

    Problem: Structural health monitoring is critical to protecting bridges against aging, : failures, and potentially collapse. However, instrumentiation techniques : suffer from non-scalability due to the high cost of instrumentation devices : and inst...

  7. Structural Determinants and Children's Oral Health: A Cross-National Study.

    Science.gov (United States)

    Baker, S R; Foster Page, L; Thomson, W M; Broomhead, T; Bekes, K; Benson, P E; Aguilar-Diaz, F; Do, L; Hirsch, C; Marshman, Z; McGrath, C; Mohamed, A; Robinson, P G; Traebert, J; Turton, B; Gibson, B J

    2018-03-01

    Much research on children's oral health has focused on proximal determinants at the expense of distal (upstream) factors. Yet, such upstream factors-the so-called structural determinants of health-play a crucial role. Children's lives, and in turn their health, are shaped by politics, economic forces, and social and public policies. The aim of this study was to examine the relationship between children's clinical (number of decayed, missing, and filled teeth) and self-reported oral health (oral health-related quality of life) and 4 key structural determinants (governance, macroeconomic policy, public policy, and social policy) as outlined in the World Health Organization's Commission for Social Determinants of Health framework. Secondary data analyses were carried out using subnational epidemiological samples of 8- to 15-y-olds in 11 countries ( N = 6,648): Australia (372), New Zealand (three samples; 352, 202, 429), Brunei (423), Cambodia (423), Hong Kong (542), Malaysia (439), Thailand (261, 506), United Kingdom (88, 374), Germany (1498), Mexico (335), and Brazil (404). The results indicated that the type of political regime, amount of governance (e.g., rule of law, accountability), gross domestic product per capita, employment ratio, income inequality, type of welfare regime, human development index, government expenditure on health, and out-of-pocket (private) health expenditure by citizens were all associated with children's oral health. The structural determinants accounted for between 5% and 21% of the variance in children's oral health quality-of-life scores. These findings bring attention to the upstream or structural determinants as an understudied area but one that could reap huge rewards for public health dentistry research and the oral health inequalities policy agenda.

  8. Neighborhood Disadvantage, Residential Segregation, and Beyond-Lessons for Studying Structural Racism and Health.

    Science.gov (United States)

    Riley, Alicia R

    2018-04-01

    A recent surge of interest in identifying the health effects of structural racism has coincided with the ongoing attention to neighborhood effects in both epidemiology and sociology. Mindful of these currents in the literature, it makes sense that we are seeing an emergent tendency in health disparities research to operationalize structural racism as either neighborhood disadvantage or racial residential segregation. This review essay synthesizes findings on the relevance of neighborhood disadvantage and residential segregation to the study of structural racism and health. It then draws on recent literature to propose four lessons for moving beyond traditional neighborhood effects approaches in the study of structural racism and health. These lessons are (1) to shift the focus of research from census tracts to theoretically meaningful units of analysis, (2) to leverage historic and geographic variation in race relations, (3) to combine data from multiple sources, and (4) to challenge normative framing that aims to explain away racial health disparities without discussing racism or racial hierarchy. The author concludes that research on the health effects of structural racism should go beyond traditional neighborhood effects approaches if it is to guide intervention to reduce racial and ethnic health disparities.

  9. Structural adjustment and health: A conceptual framework and evidence on pathways.

    Science.gov (United States)

    Kentikelenis, Alexander E

    2017-08-01

    Economic reform programs designed by the International Monetary Fund and the World Bank-so-called 'structural adjustment programs'-have formed one of the most influential policy agendas of the past four decades. To gain access to financial support from these organizations, countries-often in economic crisis-have reduced public spending, limited the role of the state, and deregulated economic activity. This article identifies the multiple components of structural adjustment, and presents a conceptual framework linking them to health systems and outcomes. Based on a comprehensive review of the academic literature, the article identifies three main pathways through which structural adjustment affects health: policies directly targeting health systems; policies indirectly impacting health systems; and policies affecting the social determinants of health. The cogency of the framework is illustrated by revisiting Greece's recent experience with structural adjustment, drawing on original IMF reports and secondary literature. Overall, the framework offers a lens through which to analyze the health consequences of structural adjustment across time, space and levels of socioeconomic development, and can be utilized in ex ante health impact assessments of these policies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Supporting Structures for Education for Sustainable Development and School-Based Health Promotion

    Science.gov (United States)

    Madsen, Katrine Dahl; Nordin, Lone Lindegaard; Simovska, Venka

    2016-01-01

    The article aims to explore the following question: "How is education for sustainable development and health education in schools approached and contextualized at a municipal level, and what contradictions and tensions might local structures imply for sustainable health promoting school development?" Based on interviews with key agents…

  11. Classroom Goal Structures and HIV and Pregnancy Prevention Education in Rural High School Health Classrooms

    Science.gov (United States)

    Anderman, Eric M.; Cupp, Pamela K.; Lane, Derek R.; Zimmerman, Rick; Gray, DeLeon L.; O'Connell, Ann

    2011-01-01

    Over 5,000 adolescents enrolled in required rural high school health courses reported their perceptions of mastery and extrinsic goal structures in their health classrooms. Data were collected from all students at three time points (prior to HIV and pregnancy instruction, 3 months after instruction, and 1 year after instruction). Results indicated…

  12. Structural Approaches to Health Promotion: What Do We Need to Know about Policy and Environmental Change?

    Science.gov (United States)

    Lieberman, Lisa; Golden, Shelley D.; Earp, Jo Anne L.

    2013-01-01

    Although the public health literature has increasingly called on practitioners to implement changes to social, environmental, and political structures as a means of improving population health, recent research suggests that articles evaluating organization, community, or policy changes are more limited than those focused on programs with…

  13. The Structure and Effectiveness of Health Systems: Exploring the Impact of System Integration in Rural China

    OpenAIRE

    Wang, Xin; Birch, Stephen; Ma, Huifen; Zhu, Weiming; Meng, Qingyue

    2016-01-01

    Introduction: Facing the challenges of aging populations, increasing chronic diseases prevalence and health system fragmentation, there have been several pilots of integrated health systems in China. But little is known about their structure, mechanism and effectiveness. The aim of this paper is to analyze health system integration and develop recommendations for achieving integration. Method: Huangzhong and Hualong counties in Qinghai province were studied as study sites, with only Huangzhon...

  14. Electronic Health Record in Occupational Medicine: Specific Aspects and Requirements of Data Structuring and Standardization

    Directory of Open Access Journals (Sweden)

    Dorin TRIFF

    2009-07-01

    Full Text Available The service of occupational medicine of a specific economic agent, as integrated part of the System of Labor Health and Safety, requires efficient, well-organized information management through standardized and computerized data processing and exploitation. Legal requirements and practical aspects of information management in occupational medicine trigger necessary operational modifications in the Electronic Health File. The goal of the paper is to present basic requirements of structuring the electronic health file and the necessary standards in recording specific data.

  15. In Situ Guided Wave Structural Health Monitoring System

    Science.gov (United States)

    Zhao, George; Tittmann, Bernhard R.

    2011-01-01

    Aircraft engine rotating equipment operates at high temperatures and stresses. Noninvasive inspection of microcracks in those components poses a challenge for nondestructive evaluation. A low-cost, low-profile, high-temperature ultrasonic guided wave sensor was developed that detects cracks in situ. The transducer design provides nondestructive evaluation of structures and materials. A key feature of the sensor is that it withstands high temperatures and excites strong surface wave energy to inspect surface and subsurface cracks. The sol-gel bismuth titanate-based surface acoustic wave (SAW) sensor can generate efficient SAWs for crack inspection. The sensor is very thin (submillimeter) and can generate surface waves up to 540 C. Finite element analysis of the SAW transducer design was performed to predict the sensor behavior, and experimental studies confirmed the results. The sensor can be implemented on structures of various shapes. With a spray-coating process, the sensor can be applied to the surface of large curvatures. It has minimal effect on airflow or rotating equipment imbalance, and provides good sensitivity.

  16. Production cost structure in US outpatient physical therapy health care.

    Science.gov (United States)

    Lubiani, Gregory G; Okunade, Albert A

    2013-02-01

    This paper investigates the technology cost structure in US physical therapy care. We exploit formal economic theories and a rich national data of providers to tease out implications for operational cost efficiencies. The 2008-2009 dataset comprising over 19 000 bi-weekly, site-specific physical therapy center observations across 28 US states and Occupational Employment Statistics data (Bureau of Labor Statistics) includes measures of output, three labor types (clinical, support, and administrative), and facilities (capital). We discuss findings from the iterative seemingly unrelated regression estimation system model. The generalized translog cost estimates indicate a well-behaved underlying technology structure. We also find the following: (i) factor demands are downwardly sloped; (ii) pair-wise factor relationships largely reflect substitutions; (iii) factor demand for physical therapists is more inelastic compared with that for administrative staff; and (iv) diminishing scale economies exist at the 25%, 50%, and 75% output (patient visits) levels. Our findings advance the timely economic understanding of operations in an increasingly important segment of the medical care sector that has, up-to-now (because of data paucity), been missing from healthcare efficiency analysis. Our work further provides baseline estimates for comparing operational efficiencies in physical therapy care after implementations of the 2010 US healthcare reforms. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Active structural health monitoring of composite plates and sandwiches

    Directory of Open Access Journals (Sweden)

    Sadílek P.

    2013-12-01

    Full Text Available The aim of presented work is to design, assemble and test a functional system, that is able to reveal damage from impact loading. This is done by monitoring of change of spectral characteristics on a damaged structure that is caused by change of mechanical properties of material or by change of structure’s geometry. Excitation and monitoring of structures was done using piezoelectric patches. Unidirectional composite plate was tested for eigenfrequencies using chirp signal. The eigenfrequencies were compared to results from experiments with an impact hammer and consequently with results from finite element method. Same method of finding eigenfrequencies was used on a different unidirectional composite specimen. Series of impacts were performed. Spectrum of eigenfrequencies was measured on undamaged plate and then after each impact. Measurements of the plate with different level of damage were compared. Following experiments were performed on sandwich materials where more different failures may happen. Set of sandwich beams (cut out from one plate made of two outer composite layers and a foam core was investigated and subjected to several impacts. Several samples were impacted in the same manner to get comparable results. The impacts were performed with growing impact energy.

  18. Coordinated robotic system for civil structural health monitoring

    Directory of Open Access Journals (Sweden)

    Qidwai Uvais

    2017-01-01

    Full Text Available With the recent advances in sensors, robotics, unmanned aerial vehicles, communication, and information technologies, it is now feasible to move towards the vision of ubiquitous cities, where virtually everything throughout the city is linked to an information system through technologies such as wireless networking and radio-frequency identification (RFID tags, to provide systematic and more efficient management of urban systems, including civil and mechanical infrastructure monitoring, to achieve the goal of resilient and sustainable societies. In this proposed system, unmanned aerial vehicle (UAVs is used to ascertain the coarse defect signature using panoramic imaging. This involves image stitching and registration so that a complete view of the surface is seen with reference to a common reference or origin point. Thereafter, crack verification and localization has been done using the magnetic flux leakage (MFL approach which has been performed with the help of a coordinated robotic system. In which the first robot is placed at the top of the structure whereas the second robot is equipped with the designed MFL sensory system. With the initial findings, the proposed system identifies and localize the crack in the given structure.

  19. A structural model of health behavior modification among patients with cardiovascular disease.

    Science.gov (United States)

    Goong, Hwasoo; Ryu, Seungmi; Xu, Lijuan

    2016-02-01

    The purpose of the study was to test a structural equation model in which social support, health beliefs, and stage of change predict the health behaviors of patients with cardiovascular disease. A cross-sectional correlational design was used. Using convenience sampling, a survey about social support, health belief, stage of change, and health behavior was completed by 314 adults with cardiovascular disease from outpatient clinics in 2 university hospitals in Korea. Data were analyzed using a structural equation model with the Analysis of Moment program. The participants were aged 53.44±13.19 years (mean±SD), and about 64% of them were male. The proposed model fit the data from the study well, explaining 19% and 60% of the variances in the stage of change and health behavior, respectively. The findings indicate that the performance of health behavior modification among the patients with cardiovascular disease can be explained by social support, health belief, and stage of change based on a health-belief and stage-of-change model. Further studies are warranted to confirm the efficacy of health-promoting strategies in initiating and maintaining the performance of health behaviors by providing social support from family and medical staff and enhancing health belief. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Advancing Research on Structural Stigma and Sexual Orientation Disparities in Mental Health Among Youth.

    Science.gov (United States)

    Hatzenbuehler, Mark L

    2017-01-01

    Psychological research on stigma has focused largely on the perceptions of stigmatized individuals and their interpersonal interactions with the nonstigmatized. This work has been critical in documenting many of the ways in which stigma operates to harm those who are targeted. However, this research has also tended to overlook broader structural forms of stigma, which refer to societal-level conditions, cultural norms, and institutional policies and practices that constrain the lives of the stigmatized. In this article I describe the emerging field of research on structural stigma and review evidence documenting the harmful consequences of structural stigma for the mental/behavioral health of lesbian, gay, and bisexual youth. This research demonstrates that structural stigma represents an important, but thus far largely underrecognized, mechanism underlying mental health disparities related to sexual orientation among youth. I offer several suggestions to advance research in this area, including (a) adopting a life-course approach to the study of structural stigma; (b) developing novel measures of structural stigma; (c) expanding both the range of methods used for studying structural stigma and the sequelae of structural stigma that are evaluated; (d) identifying potential mediators and moderators of the structural stigma-health relationship; (e) examining intersectionalities; and (f) testing generalizability of structural stigma across other groups, with a particular focus on transgender youth. The implications of this research for preventive interventions and for public policy are also discussed.

  1. A new approach for structural health monitoring by applying anomaly detection on strain sensor data

    Science.gov (United States)

    Trichias, Konstantinos; Pijpers, Richard; Meeuwissen, Erik

    2014-03-01

    Structural Health Monitoring (SHM) systems help to monitor critical infrastructures (bridges, tunnels, etc.) remotely and provide up-to-date information about their physical condition. In addition, it helps to predict the structure's life and required maintenance in a cost-efficient way. Typically, inspection data gives insight in the structural health. The global structural behavior, and predominantly the structural loading, is generally measured with vibration and strain sensors. Acoustic emission sensors are more and more used for measuring global crack activity near critical locations. In this paper, we present a procedure for local structural health monitoring by applying Anomaly Detection (AD) on strain sensor data for sensors that are applied in expected crack path. Sensor data is analyzed by automatic anomaly detection in order to find crack activity at an early stage. This approach targets the monitoring of critical structural locations, such as welds, near which strain sensors can be applied during construction and/or locations with limited inspection possibilities during structural operation. We investigate several anomaly detection techniques to detect changes in statistical properties, indicating structural degradation. The most effective one is a novel polynomial fitting technique, which tracks slow changes in sensor data. Our approach has been tested on a representative test structure (bridge deck) in a lab environment, under constant and variable amplitude fatigue loading. In both cases, the evolving cracks at the monitored locations were successfully detected, autonomously, by our AD monitoring tool.

  2. VA Health Care: Processes to Evaluate, Implement, and Monitor Organizational Structure Changes Needed

    Science.gov (United States)

    2016-09-01

    their families , such as medallions and markers for headstones that signify veterans’ service. Page 3 GAO-16-803 VHA Organizational ... Research Oversight, and Chief Nursing Page 8 GAO-16-803 VHA Organizational Structure Officer. Also, the Chief Financial Officer and...VA HEALTH CARE Processes to Evaluate, Implement, and Monitor Organizational Structure Changes Needed Report to

  3. Development of flexural vibration inspection techniques to rapidly assess the structural health of rural bridge systems

    Science.gov (United States)

    Brian K. Brashaw; Robert Vatalaro; Xiping Wang; Kevin Sarvela; James P. Wacker

    2008-01-01

    Approximately 4,000 vehicle bridges in the State of Minnesota contain structural timber members. Recent research at the University of Minnesota Duluth Natural Resources Research Institute (UMD NRRI) has been conducted on vibration testing of timber bridges as a means of developing rapid in-place testing techniques for assessing the structural health of bridges. The...

  4. The Relationship between Motivational Structure, Mental Health and Attitude to Opiate Substances in University Students

    Directory of Open Access Journals (Sweden)

    Ali akbar Soliemanian

    2012-02-01

    Full Text Available Introduction: This study was carried out with the aim of evaluating the relationship between motivational structure, mental health and attitude to opiate substances in a sample of North-Khorasan's university students. Method: In a descriptive cross-sectional study, 400 participants (200 males and 200 females were selected by stratified random sampling of three universities of north khorasan. All participants completed the SCL-90-R, Personal Concerns Inventory and Attitude to Opiate Substances questionnaire. Findings: The results revealed that there was a significant difference between participants with maladaptive motivational structure and adaptive motivational structure on GSI and subscales of SCL-90-R. In addition, the comparison of two groups showed that participants with maladaptive motivational structure had significant more positive attitude to opiate Substances than participants with adaptive motivational structure. Conclusion: There is a significant relationship between motivational structure, mental health and attitude to opiate substances.

  5. The science commons in health research: structure, function, and value.

    Science.gov (United States)

    Cook-Deegan, Robert

    The "science commons," knowledge that is widely accessible at low or no cost, is a uniquely important input to scientific advance and cumulative technological innovation. It is primarily, although not exclusively, funded by government and nonprofit sources. Much of it is produced at academic research centers, although some academic science is proprietary and some privately funded R&D enters the science commons. Science in general aspires to Mertonian norms of openness, universality, objectivity, and critical inquiry. The science commons diverges from proprietary science primarily in being open and being very broadly available. These features make the science commons particularly valuable for advancing knowledge, for training innovators who will ultimately work in both public and private sectors, and in providing a common stock of knowledge upon which all players-both public and private-can draw readily. Open science plays two important roles that proprietary R&D cannot: it enables practical benefits even in the absence of profitable markets for goods and services, and its lays a shared foundation for subsequent private R&D. The history of genomics in the period 1992-2004, covering two periods when genomic startup firms attracted significant private R&D investment, illustrates these features of how a science commons contributes value. Commercial interest in genomics was intense during this period. Fierce competition between private sector and public sector genomics programs was highly visible. Seemingly anomalous behavior, such as private firms funding "open science," can be explained by unusual business dynamics between established firms wanting to preserve a robust science commons to prevent startup firms from limiting established firms' freedom to operate. Deliberate policies to create and protect a large science commons were pursued by nonprofit and government funders of genomics research, such as the Wellcome Trust and National Institutes of Health. These

  6. Availability and structure of primary medical care services and population health and health care indicators in England

    Directory of Open Access Journals (Sweden)

    Adams Geoffrey

    2004-06-01

    Full Text Available Abstract Background It has been proposed that greater availability of primary medical care practitioners (GPs contributes to better population health. We evaluated whether measures of the supply and structure of primary medical services are associated with health and health care indicators after adjusting for confounding. Methods Data for the supply and structure of primary medical services and the characteristics of registered patients were analysed for 99 health authorities in England in 1999. Health and health care indicators as dependent variables included standardised mortality ratios (SMR, standardised hospital admission rates, and conceptions under the age of 18 years. Linear regression analyses were adjusted for Townsend score, proportion of ethnic minorities and proportion of social class IV/ V. Results Higher proportions of registered rural patients and patients ≥ 75 years were associated with lower Townsend deprivation scores, with larger partnership sizes and with better health outcomes. A unit increase in partnership size was associated with a 4.2 (95% confidence interval 1.7 to 6.7 unit decrease in SMR for all-cause mortality at 15–64 years (P = 0.001. A 10% increase in single-handed practices was associated with a 1.5 (0.2 to 2.9 unit increase in SMR (P = 0.027. After additional adjustment for percent of rural and elderly patients, partnership size and proportion of single-handed practices, GP supply was not associated with SMR (-2.8, -6.9 to 1.3, P = 0.183. Conclusions After adjusting for confounding with health needs of populations, mortality is weakly associated with the degree of organisation of practices as represented by the partnership size but not with the supply of GPs.

  7. Curative procedures of oral health and structural characteristics of primary dental care

    Directory of Open Access Journals (Sweden)

    Alexandre Baumgarten

    2018-04-01

    Full Text Available ABSTRACT OBJECTIVE To evaluate if the provision of clinical dental care, by means of the main curative procedures recommended in Primary Health Care, is associated with team structural characteristics, considering the presence of a minimum set of equipment, instrument, and supplies in Brazil’s primary health care services. METHODS A cross-sectional exploratory study based on data collected from 18,114 primary healthcare services with dental health teams in Brazil, in 2014. The outcome was created from the confirmation of five clinical procedures performed by the dentist, accounting for the presence of minimum equipment, instrument, and supplies to carry them out. Covariables were related to structural characteristics. Poisson regression with robust variance was used to obtain crude and adjusted prevalence ratios, with 95% confidence intervals. RESULTS A total of 1,190 (6.5% dental health teams did not present the minimum equipment to provide clinical dental care and only 2,498 (14.8% had all the instrument and supplies needed and provided the five curative procedures assessed. There was a positive association between the outcome and the composition of dental health teams, higher workload, performing analysis of health condition, and monitoring of oral health indicators. Additionally, the dental health teams that planned and programmed oral health actions with the primary care team monthly provided the procedures more frequently. Dentists with better employment status, career plans, graduation in public health or those who underwent permanent education activities provided the procedures more frequently. CONCLUSIONS A relevant number of Primary Health Care services did not have the infrastructure to provide clinical dental care. However, better results were found in dental health teams with oral health technicians, with higher workload and that plan their activities, as well as in those that employed dentists with better working relationships

  8. Curative procedures of oral health and structural characteristics of primary dental care

    Science.gov (United States)

    Baumgarten, Alexandre; Hugo, Fernando Neves; Bulgarelli, Alexandre Fávero; Hilgert, Juliana Balbinot

    2018-01-01

    ABSTRACT OBJECTIVE To evaluate if the provision of clinical dental care, by means of the main curative procedures recommended in Primary Health Care, is associated with team structural characteristics, considering the presence of a minimum set of equipment, instrument, and supplies in Brazil’s primary health care services. METHODS A cross-sectional exploratory study based on data collected from 18,114 primary healthcare services with dental health teams in Brazil, in 2014. The outcome was created from the confirmation of five clinical procedures performed by the dentist, accounting for the presence of minimum equipment, instrument, and supplies to carry them out. Covariables were related to structural characteristics. Poisson regression with robust variance was used to obtain crude and adjusted prevalence ratios, with 95% confidence intervals. RESULTS A total of 1,190 (6.5%) dental health teams did not present the minimum equipment to provide clinical dental care and only 2,498 (14.8%) had all the instrument and supplies needed and provided the five curative procedures assessed. There was a positive association between the outcome and the composition of dental health teams, higher workload, performing analysis of health condition, and monitoring of oral health indicators. Additionally, the dental health teams that planned and programmed oral health actions with the primary care team monthly provided the procedures more frequently. Dentists with better employment status, career plans, graduation in public health or those who underwent permanent education activities provided the procedures more frequently. CONCLUSIONS A relevant number of Primary Health Care services did not have the infrastructure to provide clinical dental care. However, better results were found in dental health teams with oral health technicians, with higher workload and that plan their activities, as well as in those that employed dentists with better working relationships, who had dentists

  9. Curative procedures of oral health and structural characteristics of primary dental care.

    Science.gov (United States)

    Baumgarten, Alexandre; Hugo, Fernando Neves; Bulgarelli, Alexandre Fávero; Hilgert, Juliana Balbinot

    2018-04-09

    To evaluate if the provision of clinical dental care, by means of the main curative procedures recommended in Primary Health Care, is associated with team structural characteristics, considering the presence of a minimum set of equipment, instrument, and supplies in Brazil's primary health care services. A cross-sectional exploratory study based on data collected from 18,114 primary healthcare services with dental health teams in Brazil, in 2014. The outcome was created from the confirmation of five clinical procedures performed by the dentist, accounting for the presence of minimum equipment, instrument, and supplies to carry them out. Covariables were related to structural characteristics. Poisson regression with robust variance was used to obtain crude and adjusted prevalence ratios, with 95% confidence intervals. A total of 1,190 (6.5%) dental health teams did not present the minimum equipment to provide clinical dental care and only 2,498 (14.8%) had all the instrument and supplies needed and provided the five curative procedures assessed. There was a positive association between the outcome and the composition of dental health teams, higher workload, performing analysis of health condition, and monitoring of oral health indicators. Additionally, the dental health teams that planned and programmed oral health actions with the primary care team monthly provided the procedures more frequently. Dentists with better employment status, career plans, graduation in public health or those who underwent permanent education activities provided the procedures more frequently. A relevant number of Primary Health Care services did not have the infrastructure to provide clinical dental care. However, better results were found in dental health teams with oral health technicians, with higher workload and that plan their activities, as well as in those that employed dentists with better working relationships, who had dentists with degrees in public health and who underwent

  10. Structural racism and health inequities in the USA: evidence and interventions.

    Science.gov (United States)

    Bailey, Zinzi D; Krieger, Nancy; Agénor, Madina; Graves, Jasmine; Linos, Natalia; Bassett, Mary T

    2017-04-08

    Despite growing interest in understanding how social factors drive poor health outcomes, many academics, policy makers, scientists, elected officials, journalists, and others responsible for defining and responding to the public discourse remain reluctant to identify racism as a root cause of racial health inequities. In this conceptual report, the third in a Series on equity and equality in health in the USA, we use a contemporary and historical perspective to discuss research and interventions that grapple with the implications of what is known as structural racism on population health and health inequities. Structural racism refers to the totality of ways in which societies foster racial discrimination through mutually reinforcing systems of housing, education, employment, earnings, benefits, credit, media, health care, and criminal justice. These patterns and practices in turn reinforce discriminatory beliefs, values, and distribution of resources. We argue that a focus on structural racism offers a concrete, feasible, and promising approach towards advancing health equity and improving population health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Conceptualizing structural change in health promotion: why we still need to know more about theory.

    Science.gov (United States)

    Gelius, Peter; Rütten, Alfred

    2017-02-28

    As recently discussed in the public health literature, many questions concerning 'structural' approaches in health promotion seem to remain unanswered. We argue that, before attempting to provide answers, it is essential to clarify the underlying theoretical assumptions in order to arrive at the right questions one should ask. To this end, we introduce into the current debate an existing theoretical framework that helps conceptualize structural and individual aspects of health promotion interventions at different levels of action. Using an example from the field of physical activity promotion, we illustrate how an integrated framework can help researchers and health promoters rethink important issues and design better interventions. In particular, such an approach may help overcome perceived distinctions between different types of approaches, re-conceptualize ideas about the effectiveness of interventions, and appropriately address issues of health disparities. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. A relational approach to health practices: towards transcending the agency-structure divide.

    Science.gov (United States)

    Veenstra, Gerry; Burnett, Patrick John

    2014-02-01

    Many health scholars find that Pierre Bourdieu's theory of practice leaves too little room for individual agency. We contend that, by virtue of its relational, field-theoretic underpinnings, the idea of leaving room for agency in Bourdieu's theory of practice is misguided. With agency manifested in interactions and social structures consisting of relations built upon relations, the stark distinction between agency and structure inherent to substantialist thinking is undermined, even dissolved, in a relational field-theoretic context. We also contend that, when treated as relationally bound phenomena, Bourdieu's notions of habitus, doxa, capital and field illuminate creative, adaptive and future-looking practices. We conclude by discussing difficulties inherent to implementing a relational theory of practice in health promotion and public health. © 2014 The Authors. Sociology of Health & Illness © 2014 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

  13. Unmanned aerial vehicle (UAV) application to the structural health assessment of large civil engineering structures

    Science.gov (United States)

    Castiglioni, Carlo A.; Rabuffetti, Angelo S.; Chiarelli, Gian P.; Brambilla, Giovanni; Georgi, Julia

    2017-09-01

    This paper summarizes the experience gained in the structural assessment of an existing Thermal Power Plant (TPP) located near Pristina, focusing on the cooling tower and the flue gas stack, which are the main structures of the TPP. Scope of the work was the evaluation of the actual conditions of the structures and to identify the eventual repair measures in order to guarantee a safe and reliable operation of the TPP in view of the extension of its operational lifetime for the next 30 years. With this aim, a sequence of different activities was performed, like: a topographic survey to compare the actual geometrical configuration with the design one, an investigation of the material properties, an in depth visual inspection in order to detect any visible existing damage. Due to the very high elevations of the constructions and to the lack of appropriate structures aimed to their inspections and maintenance, this activity could not be performed without using Unmanned Aerial Vehicle (UAV). This resulted the safest, most economical and less time-consuming solution identified to map the surface damage in the reinforced concrete elements of these large structures including zones that could not be inspected because out of reach by other means.

  14. Structural racism in the workplace: Does perception matter for health inequalities?

    Science.gov (United States)

    McCluney, Courtney L; Schmitz, Lauren L; Hicken, Margaret T; Sonnega, Amanda

    2018-02-01

    Structural racism has been linked to racial health inequalities and may operate through an unequal labor market that results in inequalities in psychosocial workplace environments (PWE). Experiences of the PWE may be a critical but understudied source of racial health disparities as most adults spend a large portion of their lives in the workplace, and work-related stress affects health outcomes. Further, it is not clear if the objective characteristics of the workplace are important for health inequalities or if these inequalities are driven by the perception of the workplace. Using data from the 2008 to 2012 waves of the Health and Retirement Study (HRS), a probability-based sample of US adults 50 years of age and older and the Department of Labor's Occupational Information Network (O*NET), we examine the role of both standardized, objective (O*NET) and survey-based, subjective (as in HRS) measures of PWEs on health and Black-White health inequalities. We find that Blacks experience more stressful PWEs and have poorer health as measured by self-rated health, episodic memory function, and mean arterial pressure. Mediation analyses suggest that these objective O*NET ratings, but not the subjective perceptions, partially explain the relationship between race and health. We discuss these results within the extant literature on workplace and health and health inequalities. Furthermore, we discuss the use of standardized objective measures of the PWE to capture racial inequalities in workplace environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Redesigning a Ministry of Health's organizational structure: exploring implementation challenges through Botswana's experiences.

    Science.gov (United States)

    Seitio-Kgokgwe, Onalenna; Gauld, Robin D C; Hill, Philip C; Barnett, Pauline

    2016-04-01

    The Botswana's Ministry of Health redesigned and adopted a new organizational structure in 2005, which was poorly implemented. This article explores factors that influenced the implementation of this organizational structure. This article draws from data collected through in-depth interviews with 54 purposively selected key informants comprising policy makers, senior managers and staff of the Ministry of Health (N = 40) and senior officers from various stakeholder organizations (N = 14). Participants generally felt that the review of the Ministry of Health organizational structure was important. The previous structure was considered obsolete with fragmented functions that limited the overall performance of the health system. The new organizational structure was viewed to be aligned to current national priorities with potential to positively influence performance. Some key weaknesses identified included lack of consultation and information sharing with workers during the restructuring process, which affected the understanding of their new roles, failure to mobilize key resources to support implementation of the new structure and inadequate monitoring of the implementation process. Redesigning an organizational structure is a major change. There is a need for effective and sustained leadership to plan, direct, coordinate, monitor and evaluate the implementation phase of the reform. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Structural issues affecting mixed methods studies in health research: a qualitative study

    Science.gov (United States)

    2009-01-01

    Background Health researchers undertake studies which combine qualitative and quantitative methods. Little attention has been paid to the structural issues affecting this mixed methods approach. We explored the facilitators and barriers to undertaking mixed methods studies in health research. Methods Face-to-face semi-structured interviews with 20 researchers experienced in mixed methods research in health in the United Kingdom. Results Structural facilitators for undertaking mixed methods studies included a perception that funding bodies promoted this approach, and the multidisciplinary constituency of some university departments. Structural barriers to exploiting the potential of these studies included a lack of education and training in mixed methods research, and a lack of templates for reporting mixed methods articles in peer-reviewed journals. The 'hierarchy of evidence' relating to effectiveness studies in health care research, with the randomised controlled trial as the gold standard, appeared to pervade the health research infrastructure. Thus integration of data and findings from qualitative and quantitative components of mixed methods studies, and dissemination of integrated outputs, tended to occur through serendipity and effort, further highlighting the presence of structural constraints. Researchers are agents who may also support current structures - journal reviewers and editors, and directors of postgraduate training courses - and thus have the ability to improve the structural support for exploiting the potential of mixed methods research. Conclusion The environment for health research in the UK appears to be conducive to mixed methods research but not to exploiting the potential of this approach. Structural change, as well as change in researcher behaviour, will be necessary if researchers are to fully exploit the potential of using mixed methods research. PMID:20003210

  17. Structural issues affecting mixed methods studies in health research: a qualitative study.

    Science.gov (United States)

    O'Cathain, Alicia; Nicholl, Jon; Murphy, Elizabeth

    2009-12-09

    Health researchers undertake studies which combine qualitative and quantitative methods. Little attention has been paid to the structural issues affecting this mixed methods approach. We explored the facilitators and barriers to undertaking mixed methods studies in health research. Face-to-face semi-structured interviews with 20 researchers experienced in mixed methods research in health in the United Kingdom. Structural facilitators for undertaking mixed methods studies included a perception that funding bodies promoted this approach, and the multidisciplinary constituency of some university departments. Structural barriers to exploiting the potential of these studies included a lack of education and training in mixed methods research, and a lack of templates for reporting mixed methods articles in peer-reviewed journals. The 'hierarchy of evidence' relating to effectiveness studies in health care research, with the randomised controlled trial as the gold standard, appeared to pervade the health research infrastructure. Thus integration of data and findings from qualitative and quantitative components of mixed methods studies, and dissemination of integrated outputs, tended to occur through serendipity and effort, further highlighting the presence of structural constraints. Researchers are agents who may also support current structures - journal reviewers and editors, and directors of postgraduate training courses - and thus have the ability to improve the structural support for exploiting the potential of mixed methods research. The environment for health research in the UK appears to be conducive to mixed methods research but not to exploiting the potential of this approach. Structural change, as well as change in researcher behaviour, will be necessary if researchers are to fully exploit the potential of using mixed methods research.

  18. Frequency and prioritization of patient health risks from a structured health risk assessment.

    Science.gov (United States)

    Phillips, Siobhan M; Glasgow, Russell E; Bello, Ghalib; Ory, Marcia G; Glenn, Beth A; Sheinfeld-Gorin, Sherri N; Sabo, Roy T; Heurtin-Roberts, Suzanne; Johnson, Sallie Beth; Krist, Alex H

    2014-01-01

    To describe the frequency and patient-reported readiness to change, desire to discuss, and perceived importance of 13 health risk factors in a diverse range of primary care practices. Patients (n = 1,707) in 9 primary care practices in the My Own Health Report (MOHR) trial reported general, behavioral, and psychosocial risk factors (body mass index [BMI], health status, diet, physical activity, sleep, drug use, stress, anxiety or worry, and depression). We classified responses as "at risk" or "healthy" for each factor, and patients indicated their readiness to change and/or desire to discuss identified risk factors with providers. Patients also selected 1 of the factors they were ready to change as most important. We then calculated frequencies within and across these factors and examined variation by patient characteristics and across practices. On average, patients had 5.8 (SD = 2.12; range, 0-13) unhealthy behaviors and mental health risk factors. About 55% of patients had more than 6 risk factors. On average, patients wanted to change 1.2 and discuss 0.7 risks. The most common risks were inadequate fruit/vegetable consumption (84.5%) and overweight/obesity (79.6%). Patients were most ready to change BMI (33.3%) and depression (30.7%), and most wanted to discuss depression (41.9%) and anxiety or worry (35.2%). Overall, patients rated health status as most important. Implementing routine comprehensive health risk assessments in primary care will likely identify a high number of behavioral and psychosocial health risks. By soliciting patient priorities, providers and patients can better manage counseling and behavior change. © 2014 Annals of Family Medicine, Inc.

  19. Examining clinicians’ experiences providing sexual health services for LGBTQ youth: considering social and structural determinants of health in clinical practice

    Science.gov (United States)

    Knight, R. E.; Shoveller, J. A.; Carson, A. M.; Contreras-Whitney, J. G.

    2014-01-01

    Although barriers related to lesbian, gay, bisexual, transgender and queer (LGBTQ) youth’s experiences accessing sexual health services have been examined in detail, research into the experiences and perceptions of clinicians providing these services has been conspicuously absent. The aim of this article is to explore the perceptions and experiences of clinicians providing sexual health services for LGBTQ youth. Drawing on in-depth, semi-structured interviews, this study examines 24 clinicians’ experiences providing sexual health services to LGBTQ youth in five communities in British Columbia, Canada. Our findings reveal how many clinicians provide services to LGBTQ youth with a lack of cultural competency—either implicitly (e.g. by describing heteronormative practices) or explicitly (e.g. by expressing frustration that they had not been sufficiently provided with appropriate training related to LGBTQ youth sexual health). Institutional norms and values were identified as the dominant barriers in the effective provision of LGBTQ-tailored services. Many clinicians find themselves unprepared to provide culturally competent sexual health services that have both the capacity to address individual-level issues (e.g. promoting condom use) while considering (and adapting services to) the broader socio-cultural and structural conditions that can render LGBTQ youth socially vulnerable. PMID:24412811

  20. A taxonomy of state public health preparedness units: an empirical examination of organizational structure.

    Science.gov (United States)

    Menachemi, Nir; Yeager, Valerie A; Duncan, W Jack; Katholi, Charles R; Ginter, Peter M

    2012-01-01

    State public health preparedness units (SPHPUs) were developed in response to federal funding to improve response to disasters: a responsibility that had not traditionally been within the purview of public health. The SPHPUs were created within the existing public health organizational structure, and their placement may have implications for how the unit functions, how communication takes place, and ultimately how well the key responsibilities are performed. This study empirically identifies a taxonomy of similarly structured SPHPUs and examines whether this structure is associated with state geographic, demographic, and threat-vulnerability characteristics. Data representing each SPHPU were extracted from publically available sources, including organizational charts and emergency preparedness plans for 2009. A cross-sectional segmentation analysis was conducted of variables representing structural attributes. Fifty state public health departments. Variables representing "span of control" and "hierarchal levels" were extracted from organizational charts. Structural "complexity" and "centralization" were extracted from state emergency preparedness documents and other secondary sources. On average, 6.6 people report to the same manager as the SPHPU director; 2.1 levels separate the SPHPU director from the state health officer; and a mean of 13.5 agencies collaborate with SPHPU during a disaster. Despite considerable variability in how SPHPUs had been structured, results of the cluster and principal component analysis identified 7 similarly structured groups. Neither the taxonomic groups nor the individual variables representing structure were found to be associated with state characteristics, including threat vulnerabilities. Our finding supports the hypothesis that SPHPUs are seemingly inadvertently (eg, not strategically) organized. This taxonomy provides the basis for which future research can examine how SPHPU structure relates to performance measures and

  1. A mobile sensing system for structural health monitoring: design and validation

    International Nuclear Information System (INIS)

    Zhu, Dapeng; Yi, Xiaohua; Wang, Yang; Lee, Kok-Meng; Guo, Jiajie

    2010-01-01

    This paper describes a new approach using mobile sensor networks for structural health monitoring. Compared with static sensors, mobile sensor networks offer flexible system architectures with adaptive spatial resolutions. The paper first describes the design of a mobile sensing node that is capable of maneuvering on structures built with ferromagnetic materials. The mobile sensing node can also attach/detach an accelerometer onto/from the structural surface. The performance of the prototype mobile sensor network has been validated through laboratory experiments. Two mobile sensing nodes are adopted for navigating on a steel portal frame and providing dense acceleration measurements. Transmissibility function analysis is conducted to identify structural damage using data collected by the mobile sensing nodes. This preliminary work is expected to spawn transformative changes in the use of mobile sensors for future structural health monitoring

  2. A mobile sensing system for structural health monitoring: design and validation

    Science.gov (United States)

    Zhu, Dapeng; Yi, Xiaohua; Wang, Yang; Lee, Kok-Meng; Guo, Jiajie

    2010-05-01

    This paper describes a new approach using mobile sensor networks for structural health monitoring. Compared with static sensors, mobile sensor networks offer flexible system architectures with adaptive spatial resolutions. The paper first describes the design of a mobile sensing node that is capable of maneuvering on structures built with ferromagnetic materials. The mobile sensing node can also attach/detach an accelerometer onto/from the structural surface. The performance of the prototype mobile sensor network has been validated through laboratory experiments. Two mobile sensing nodes are adopted for navigating on a steel portal frame and providing dense acceleration measurements. Transmissibility function analysis is conducted to identify structural damage using data collected by the mobile sensing nodes. This preliminary work is expected to spawn transformative changes in the use of mobile sensors for future structural health monitoring.

  3. Structuring and coding in health care records: a qualitative analysis using diabetes as a case study.

    Science.gov (United States)

    Robertson, Ann R R; Fernando, Bernard; Morrison, Zoe; Kalra, Dipak; Sheikh, Aziz

    2015-03-27

    Globally, diabetes mellitus presents a substantial and increasing burden to individuals, health care systems and society. Structuring and coding of information in the electronic health record underpin attempts to improve sharing and searching for information. Digital records for those with long-term conditions are expected to bring direct and secondary uses benefits, and potentially to support patient self-management. We sought to investigate if how and why records for adults with diabetes were structured and coded and to explore a range of UK stakeholders' perceptions of current practice in the National Health Service. We carried out a qualitative, theoretically informed case study of documenting health care information for diabetes in family practice and hospital settings in England, using semi-structured interviews, observations, systems demonstrations and documentary data. We conducted 22 interviews and four on-site observations. With respect to secondary uses - research, audit, public health and service planning - interviewees clearly articulated the benefits of highly structured and coded diabetes data and it was believed that benefits would expand through linkage to other datasets. Direct, more marginal, clinical benefits in terms of managing and monitoring diabetes and perhaps encouraging patient self-management were also reported. We observed marked differences in levels of record structuring and/or coding between family practices, where it was high, and the hospital. We found little evidence that structured and coded data were being exploited to improve information sharing between care settings. Using high levels of data structuring and coding in records for diabetes patients has the potential to be exploited more fully, and lessons might be learned from successful developments elsewhere in the UK. A first step would be for hospitals to attain levels of health information technology infrastructure and systems use commensurate with family practices.

  4. Structural damage detection for in-service highway bridge under operational and environmental variability

    Science.gov (United States)

    Jin, Chenhao; Li, Jingcheng; Jang, Shinae; Sun, Xiaorong; Christenson, Richard

    2015-03-01

    Structural health monitoring has drawn significant attention in the past decades with numerous methodologies and applications for civil structural systems. Although many researchers have developed analytical and experimental damage detection algorithms through vibration-based methods, these methods are not widely accepted for practical structural systems because of their sensitivity to uncertain environmental and operational conditions. The primary environmental factor that influences the structural modal properties is temperature. The goal of this article is to analyze the natural frequency-temperature relationships and detect structural damage in the presence of operational and environmental variations using modal-based method. For this purpose, correlations between natural frequency and temperature are analyzed to select proper independent variables and inputs for the multiple linear regression model and neural network model. In order to capture the changes of natural frequency, confidence intervals to detect the damages for both models are generated. A long-term structural health monitoring system was installed on an in-service highway bridge located in Meriden, Connecticut to obtain vibration and environmental data. Experimental testing results show that the variability of measured natural frequencies due to temperature is captured, and the temperature-induced changes in natural frequencies have been considered prior to the establishment of the threshold in the damage warning system. This novel approach is applicable for structural health monitoring system and helpful to assess the performance of the structure for bridge management and maintenance.

  5. Damage Detection in an Offshore Structure

    DEFF Research Database (Denmark)

    Brincker, Rune; Kirkegaard, Poul Henning; Andersen, P.

    The structural integrity of a multi-pile offshore platform is investigated by using a vibration based damage detection scheme. Changes in structural integrity are assumed to be reflected in the modal parameters estimated from only output data using an Auto-Regressive Moving Average (ARMA) model....... By use of the estimates of the modal parameters and their corresponding variances a probability based damage indicator is formulated. This approach indicates, that since the construction of the platform, minor structural changes have taken place....

  6. Damage Detection in an Offshore Structure

    DEFF Research Database (Denmark)

    Brincker, Rune; Kirkegaard, Poul Henning; Andersen, Palle

    1995-01-01

    The structural integrity of a multi-pile offshore platform is investigated by using a vibration based damage detection scheme. Changes in structural integrity are assumed to be reflected in the modal parameters estimated from only output data using an Auto-Regressive Moving Average (ARMA) model....... By use of the estimates of the modal parameters and their corresponding variances a probability based damage indicator is formulated. This approach indicates, that since the construction of the platform, minor structural changes have taken place....

  7. Cointegration as a data normalization tool for structural health monitoring applications

    Science.gov (United States)

    Harvey, Dustin Y.; Todd, Michael D.

    2012-04-01

    The structural health monitoring literature has shown an abundance of features sensitive to various types of damage in laboratory tests. However, robust feature extraction in the presence of varying operational and environmental conditions has proven to be one of the largest obstacles in the development of practical structural health monitoring systems. Cointegration, a technique adapted from the field of econometrics, has recently been introduced to the SHM field as one solution to the data normalization problem. Response measurements and feature histories often show long-run nonstationarity due to fluctuating temperature, load conditions, or other factors that leads to the occurrence of false positives. Cointegration theory allows nonstationary trends common to two or more time series to be modeled and subsequently removed. Thus, the residual retains sensitivity to damage with dependence on operational and environmental variability removed. This study further explores the use of cointegration as a data normalization tool for structural health monitoring applications.

  8. The Structure and Effectiveness of Health Systems: Exploring the Impact of System Integration in Rural China

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-08-01

    Full Text Available Introduction: Facing the challenges of aging populations, increasing chronic diseases prevalence and health system fragmentation, there have been several pilots of integrated health systems in China. But little is known about their structure, mechanism and effectiveness. The aim of this paper is to analyze health system integration and develop recommendations for achieving integration. Method: Huangzhong and Hualong counties in Qinghai province were studied as study sites, with only Huangzhong having implemented health system integration. Questionnaires, interviews, and health ­insurance records were sources of data. Social network analysis was employed to analyze integration, through structure measurement and effectiveness evaluation. Results: Health system integration in Huangzhong is higher than in Hualong, so is system ­effectiveness. The patient referral network in Hualong has more “leapfrog” referrals. The information sharing ­networks in both counties are larger than the other types of networks. The average distance in the joint ­training network of Huangzhong is less than in Hualong. Meanwhile, there are deficiencies common to both systems. Conclusion: Both county health systems have strengths and limitations regarding system integration. The use of medical consortia in Huangzhong has contributed to system effectiveness. Future research might consider alternative more context specific models of health system integration.

  9. The Structure and Effectiveness of Health Systems: Exploring the Impact of System Integration in Rural China.

    Science.gov (United States)

    Wang, Xin; Birch, Stephen; Ma, Huifen; Zhu, Weiming; Meng, Qingyue

    2016-08-12

    Facing the challenges of aging populations, increasing chronic diseases prevalence and health system fragmentation, there have been several pilots of integrated health systems in China. But little is known about their structure, mechanism and effectiveness. The aim of this paper is to analyze health system integration and develop recommendations for achieving integration. Huangzhong and Hualong counties in Qinghai province were studied as study sites, with only Huangzhong having implemented health system integration. Questionnaires, interviews, and health insurance records were sources of data. Social network analysis was employed to analyze integration, through structure measurement and effectiveness evaluation. Health system integration in Huangzhong is higher than in Hualong, so is system effectiveness. The patient referral network in Hualong has more "leapfrog" referrals. The information sharing networks in both counties are larger than the other types of networks. The average distance in the joint training network of Huangzhong is less than in Hualong. Meanwhile, there are deficiencies common to both systems. Both county health systems have strengths and limitations regarding system integration. The use of medical consortia in Huangzhong has contributed to system effectiveness. Future research might consider alternative more context specific models of health system integration.

  10. A Demonstration of Concrete Structural Health Monitoring Framework for Degradation due to Alkali-Silica Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Mahadevan, Sankaran [Idaho National Lab. (INL), Idaho Falls, ID (United States); Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States); Neal, Kyle [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nath, Paromita [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bao, Yanqing [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cai, Guowei [Idaho National Lab. (INL), Idaho Falls, ID (United States); Orme, Peter [Idaho National Lab. (INL), Idaho Falls, ID (United States); Adams, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kosson, David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-04-01

    Assessment and management of aging concrete structures in nuclear power plants require a more systematic approach than simple reliance on existing code margins of safety. Structural health monitoring of concrete structures aims to understand the current health condition of a structure based on heterogeneous measurements to produce high-confidence actionable information regarding structural integrity that supports operational and maintenance decisions. This ongoing research project is seeking to develop a probabilistic framework for health diagnosis and prognosis of aging concrete structures in a nuclear power plant that is subjected to physical, chemical, environment, and mechanical degradation. The proposed framework consists of four elements: monitoring, data analytics, uncertainty quantification and prognosis. This report focuses on degradation caused by ASR (alkali-silica reaction). Controlled specimens were prepared to develop accelerated ASR degradation. Different monitoring techniques – thermography, digital image correlation (DIC), mechanical deformation measurements, nonlinear impact resonance acoustic spectroscopy (NIRAS), and vibro-acoustic modulation (VAM) -- were used to detect the damage caused by ASR. Heterogeneous data from the multiple techniques was used for damage diagnosis and prognosis, and quantification of the associated uncertainty using a Bayesian network approach. Additionally, MapReduce technique has been demonstrated with synthetic data. This technique can be used in future to handle large amounts of observation data obtained from the online monitoring of realistic structures.

  11. Synthesis of vibration control and health monitoring of building structures under unknown excitation

    International Nuclear Information System (INIS)

    He, Jia; Huang, Qin; Xu, You-Lin

    2014-01-01

    The vibration control and health monitoring of building structures have been actively investigated in recent years but often treated separately according to the primary objective pursued. In this study, a time-domain integrated vibration control and health monitoring approach is proposed based on the extended Kalman filter (EKF) for identifying the physical parameters of the controlled building structures without the knowledge of the external excitation. The physical parameters and state vectors of the building structure are then estimated and used for the determination of the control force for the purpose of the vibration attenuation. The interaction between the health monitoring and vibration control is revealed and assessed. The feasibility and reliability of the proposed approach is numerically demonstrated via a five-story shear building structure equipped with magneto-rheological (MR) dampers. Two types of excitations are considered: (1) the EI-Centro ground excitation underneath of the building and (2) a swept-frequency excitation applied on the top floor of the building. Results show that the structural parameters as well as the unknown dynamic loadings could be identified accurately; and, at the same time, the structural vibration is significantly reduced in the building structure. (paper)

  12. Stress Prediction for Distributed Structural Health Monitoring Using Existing Measurements and Pattern Recognition.

    Science.gov (United States)

    Lu, Wei; Teng, Jun; Zhou, Qiushi; Peng, Qiexin

    2018-02-01

    The stress in structural steel members is the most useful and directly measurable physical quantity to evaluate the structural safety in structural health monitoring, which is also an important index to evaluate the stress distribution and force condition of structures during structural construction and service phases. Thus, it is common to set stress as a measure in steel structural monitoring. Considering the economy and the importance of the structural members, there are only a limited number of sensors that can be placed, which means that it is impossible to obtain the stresses of all members directly using sensors. This study aims to develop a stress response prediction method for locations where there are insufficent sensors, using measurements from a limited number of sensors and pattern recognition. The detailed improved aspects are: (1) a distributed computing process is proposed, where the same pattern is recognized by several subsets of measurements; and (2) the pattern recognition using the subset of measurements is carried out by considering the optimal number of sensors and number of fusion patterns. The validity and feasibility of the proposed method are verified using two examples: the finite-element simulation of a single-layer shell-like steel structure, and the structural health monitoring of the space steel roof of Shenzhen Bay Stadium; for the latter, the anti-noise performance of this method is verified by the stress measurements from a real-world project.

  13. Preparing a Health Care White Paper: Providing Structure to the Writing Process.

    Science.gov (United States)

    Rotarius, Timothy; Rotarius, Velmarie

    2016-01-01

    Health care leaders operate in a very complex and turbulent business environment. Both government regulations and market forces are very active in the industry. Thus, health care managers have many multifaceted and, sometimes, contradictory expectations placed upon them and their organizations. To ensure professional accountability, health care executives often join professional associations and strive for licenses and certifications that are intended to place the professional above the rest. One important avenue to achieve various licensing and certification accomplishments involves writing a white paper about a specific topic of interest to the industry and organization. Presented herein are structural processes that facilitate the creation and preparation of a health care white paper. Both conceptual and empirical structures of white papers are presented, with the similarities and the differences between conceptual and empirical papers highlighted.

  14. History, Structure and Agency in Global Health Governance Comment on "Global Health Governance Challenges 2016 - Are We Ready?"

    Science.gov (United States)

    Gill, Stephen; Benatar, Solomon R

    2016-08-29

    Ilona Kickbusch's thought provoking editorial is criticized in this commentary, partly because she fails to refer to previous critical work on the global conditions and policies that sustain inequality, poverty, poor health and damage to the biosphere and, as a result, she misreads global power and elides consideration of the fundamental historical structures of political and material power that shape agency in global health governance. We also doubt that global health can be improved through structures and processes of multilateralism that are premised on the continued reproduction of the ecologically myopic and socially unsustainable market civilization model of capitalist development that currently prevails in the world economy. This model drives net financial flows from poor to rich countries and from the poor to the affluent and super wealthy individuals. By contrast, we suggest that significant progress in global health requires a profound and socially just restructuring of global power, greater global solidarity and the "development of sustainability." © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  15. Scope of Policy Issues in eHealth: Results From a Structured Literature Review

    Science.gov (United States)

    Durrani, Hammad; Nayani, Parvez; Fahim, Ammad

    2012-01-01

    Background eHealth is widely used as a tool for improving health care delivery and information. However, distinct policies and strategies are required for its proper implementation and integration at national and international levels. Objective To determine the scope of policy issues faced by individuals, institutions, or governments in implementing eHealth programs. Methods We conducted a structured review of both peer-reviewed and gray literature from 1998–2008. A Medline search for peer-reviewed articles found 40 papers focusing on different aspects of eHealth policy. In addition, a Google search found 20 national- and international-level policy papers and documents. We reviewed these articles to extract policy issues and solutions described at different levels of care. Results The literature search found 99 policy issues related to eHealth. We grouped these issues under the following themes: (1) networked care, (2) interjurisdictional practice, (3) diffusion of eHealth/digital divide, (4) eHealth integration with existing systems, (5) response to new initiatives, (6) goal-setting for eHealth policy, (7) evaluation and research, (8) investment, and (9) ethics in eHealth. Conclusions We provide a list of policy issues that should be understood and addressed by policy makers at global, jurisdictional, and institutional levels, to facilitate smooth and reliable planning of eHealth programs. PMID:22343270

  16. Corruption and population health outcomes: an analysis of data from 133 countries using structural equation modeling.

    Science.gov (United States)

    Factor, Roni; Kang, Minah

    2015-09-01

    The current study aims to develop a theoretical framework for understanding the antecedents of corruption and the effects of corruption on various health indicators. Using structural equation models, we analyzed a multinational dataset of 133 countries that included three main groups of variables--antecedents of corruption, corruption measures, and health indicators. Controlling for various factors, our results suggest that corruption rises as GDP per capita falls and as the regime becomes more autocratic. Higher corruption is associated with lower levels of health expenditure as a percentage of GDP per capita, and with poorer health outcomes. Countries with higher GDP per capita and better education for women have better health outcomes regardless of health expenditures and regime type. Our results suggest that there is no direct relationship between health expenditures and health outcomes after controlling for the other factors in the model. Our study enhances our understanding of the conceptual and theoretical links between corruption and health outcomes in a population, including factors that may mediate how corruption can affect health outcomes.

  17. Goals and organisational structure of the movement for global mental health.

    Science.gov (United States)

    Minas, Harry; Wright, Alexandra; Kakuma, Ritsuko

    2014-01-01

    The Movement for Global Mental Health (MGMH), established in 2008, is in a period of transition, as is the field of global mental health. The transfer of Secretariat functions from the Centre for International Mental Health to the Public Health Foundation of India was a suitable time to reflect on the goals of MGMH and on the form of organisational structure that would best serve the organisation in its efforts to achieve its goals. An online survey was sent to the 4,000 registered members of MGMH seeking the views of the membership on both the goals of MGMH and on the preferred form of organisational structure. There was near unanimous (95%) agreement with the MGMH goals as stated at the time of the survey. The current form of organisation of MGMH, a loose network of individuals and organisations registered through the MGMH website, was the least preferred (29.9%) form of organisation for the future of MGMH. More than two thirds (70.1%) of respondents would prefer a formal legal structure, with 60% of this group favouring a Charitable Organisation structure and 40% preferring an international Association structure. The response rate (7%) was too small and too skewed (predominantly academics and health professionals from high income countries) to allow any clear conclusions to be drawn from the survey. However, both the fact that responses were too few and skewed and the preferences expressed by respondents raise issues for careful consideration by the current MGMH Secretariat. The global mental health field and MGMH are in a time of transition. The move to the new secretariat is an opportunity for systematic consideration of the organisational structure and governance arrangements that will best serve the goals of MGMH.

  18. Experimental Research on Quick Structural Health Monitoring Technique for Bridges Using Smartphone

    OpenAIRE

    Zhao, Xuefeng; Ri, Kwang; Han, Ruicong; Yu, Yan; Li, Mingchu; Ou, Jinping

    2016-01-01

    In the recent years, with the development and popularization of smartphone, the utilization of smartphone in the Structural Health Monitoring (SHM) has attracted increasing attention owing to its unique feature. Since bridges are of great importance to society and economy, bridge health monitoring has very practical significance during its service life. Furthermore, rapid damage assessment of bridge after an extreme event such as earthquake is very important in the recovery work. Smartphone-b...

  19. Effectiveness of structured teaching programme on knowledge regarding sexual health among young adults

    OpenAIRE

    Atul Kumar; Mahalingam Venkateshan; Selvi

    2016-01-01

    Background: Adulthood is the pinnacle of all stages of human growth and development. Sexuality plays the axial role in all the spheres of human life. Individual's health can be regarded on the reciprocal function of his sexuality and sexual practices. Abnormal sexuality results in deviation in physical, physiological, psychological and even economical disturbances. The main aim of the study was to evaluate the effectiveness of structured teaching programme on knowledge regarding sexual health...

  20. Managing structural uncertainty in health economic decision models: a discrepancy approach

    OpenAIRE

    Strong, M.; Oakley, J.; Chilcott, J.

    2012-01-01

    Healthcare resource allocation decisions are commonly informed by computer model predictions of population mean costs and health effects. It is common to quantify the uncertainty in the prediction due to uncertain model inputs, but methods for quantifying uncertainty due to inadequacies in model structure are less well developed. We introduce an example of a model that aims to predict the costs and health effects of a physical activity promoting intervention. Our goal is to develop a framewor...

  1. Application of eco-exergy for assessment of ecosystem health and development of structurally dynamic models

    DEFF Research Database (Denmark)

    Zhang, J.; Gürkan, Zeren; Jørgensen, S.E.

    2010-01-01

    are developed using eco-exergy as the goal function, have been applied in explaining and exploring ecosystem properties and changes in community structure driven by biotic and abiotic factors. In this paper, we review the application of eco-exergy for the assessment of ecosystem health and development......Eco-exergy has been widely used in the assessment of ecosystem health, parameter estimations, calibrations, validations and prognoses. It offers insights into the understanding of ecosystem dynamics and disturbance-cl riven changes. Particularly, structurally dynamic models (SDMs), which...

  2. Evaluation of Health Equity Impact of Structural Policies: Overview of Research Methods Used in the SOPHIE Project

    NARCIS (Netherlands)

    Kunst, Anton E.

    2017-01-01

    This article briefly assesses the research methods that were applied in the SOPHIE project to evaluate the impact of structural policies on population health and health inequalities. The evaluation of structural policies is one of the key methodological challenges in today's public health. The

  3. Structural Vulnerability and Health: Latino Migrant Laborers in the United States

    Science.gov (United States)

    Quesada, James; Hart, Laurie K.; Bourgois, Philippe

    2011-01-01

    Latino immigrants in the United States constitute a paradigmatic case of a population group subject to structural violence. Their subordinated location in the global economy and their culturally depreciated status in the United States are exacerbated by legal persecution. Medical Anthropology Volume 30, issues 4 and 5, include a series of ethnographic analyses of the processes that render undocumented Latino immigrants structurally vulnerable to ill-health. We hope to extend the social science concept of ‘structural vulnerability’ to make it a useful tool for health care. Defined as a positionality that imposes physical/emotional suffering on specific population groups and individuals in patterned ways, structural vulnerability is a product of two complementary forces: (1) class-based economic exploitation and cultural, gender/sexual, and racialized discrimination; and (2) processes of symbolic violence and subjectivity formation that have increasingly legitimized punitive neoliberal discourses of individual unworthiness. PMID:21777121

  4. Development and Application of a Structural Health Monitoring System Based on Wireless Smart Aggregates.

    Science.gov (United States)

    Yan, Shi; Ma, Haoyan; Li, Peng; Song, Gangbing; Wu, Jianxin

    2017-07-17

    Structural health monitoring (SHM) systems can improve the safety and reliability of structures, reduce maintenance costs, and extend service life. Research on concrete SHMs using piezoelectric-based smart aggregates have reached great achievements. However, the newly developed techniques have not been widely applied in practical engineering, largely due to the wiring problems associated with large-scale structural health monitoring. The cumbersome wiring requires much material and labor work, and more importantly, the associated maintenance work is also very heavy. Targeting a practical large scale concrete crack detection (CCD) application, a smart aggregates-based wireless sensor network system is proposed for the CCD application. The developed CCD system uses Zigbee 802.15.4 protocols, and is able to perform dynamic stress monitoring, structural impact capturing, and internal crack detection. The system has been experimentally validated, and the experimental results demonstrated the effectiveness of the proposed system. This work provides important support for practical CCD applications using wireless smart aggregates.

  5. Long-term real-time structural health monitoring using wireless smart sensor

    Science.gov (United States)

    Jang, Shinae; Mensah-Bonsu, Priscilla O.; Li, Jingcheng; Dahal, Sushil

    2013-04-01

    Improving the safety and security of civil infrastructure has become a critical issue for decades since it plays a central role in the economics and politics of a modern society. Structural health monitoring of civil infrastructure using wireless smart sensor network has emerged as a promising solution recently to increase structural reliability, enhance inspection quality, and reduce maintenance costs. Though hardware and software framework are well prepared for wireless smart sensors, the long-term real-time health monitoring strategy are still not available due to the lack of systematic interface. In this paper, the Imote2 smart sensor platform is employed, and a graphical user interface for the long-term real-time structural health monitoring has been developed based on Matlab for the Imote2 platform. This computer-aided engineering platform enables the control, visualization of measured data as well as safety alarm feature based on modal property fluctuation. A new decision making strategy to check the safety is also developed and integrated in this software. Laboratory validation of the computer aided engineering platform for the Imote2 on a truss bridge and a building structure has shown the potential of the interface for long-term real-time structural health monitoring.

  6. Structural health monitoring (vibration) as a tool for identifying structural alterations of the lumbar spine: a twin control study.

    Science.gov (United States)

    Kawchuk, Gregory N; Hartvigsen, Jan; Edgecombe, Tiffany; Prasad, Narasimha; van Dieen, Jaap H

    2016-03-11

    Structural health monitoring (SHM) is an engineering technique used to identify mechanical abnormalities not readily apparent through other means. Recently, SHM has been adapted for use in biological systems, but its invasive nature limits its clinical application. As such, the purpose of this project was to determine if a non-invasive form of SHM could identify structural alterations in the spines of living human subjects. Lumbar spines of 10 twin pairs were visualized by magnetic resonance imaging then assessed by a blinded radiologist to determine whether twin pairs were structurally concordant or discordant. Vibration was then applied to each subject's spine and the resulting response recorded from sensors overlying lumbar spinous processes. The peak frequency, area under the curve and the root mean square were computed from the frequency response function of each sensor. Statistical analysis demonstrated that in twins whose structural appearance was discordant, peak frequency was significantly different between twin pairs while in concordant twins, no outcomes were significantly different. From these results, we conclude that structural changes within the spine can alter its vibration response. As such, further investigation of SHM to identify spinal abnormalities in larger human populations is warranted.

  7. Structural health monitoring system of soccer arena based on optical sensors

    Science.gov (United States)

    Shishkin, Victor V.; Churin, Alexey E.; Kharenko, Denis S.; Zheleznova, Maria A.; Shelemba, Ivan S.

    2014-05-01

    A structural health monitoring system based on optical sensors has been developed and installed on the indoor soccer arena "Zarya" in Novosibirsk. The system integrates 119 fiber optic sensors: 85 strain, 32 temperature and 2 displacement sensors. In addition, total station is used for measuring displacement in 45 control points. All of the constituents of the supporting structure are subjects for monitoring: long-span frames with under floor ties, connections, purlins and foundation.

  8. A Wireless Sensor Network for Structural Health Monitoring: Performance and Experience

    OpenAIRE

    Paek, Jeongyeup; Chintalapudi, Krishna; Caffrey, John; Govindan, Ramesh; Masri, Sami

    2005-01-01

    While sensor network research has made significant strides in the past few years, the literature has relatively few examples of papers that have evaluated and validated a complete experimental system. In this paper we discuss our deployment experiences and evaluate the performance of a multi-hop wireless data acquisition system (called Wisden) for structural health monitoring (SHM) on a large seismic test structure used by civil engineers. Our experiments indicate that, with the latest sensor...

  9. Statistical time series methods for damage diagnosis in a scale aircraft skeleton structure: loosened bolts damage scenarios

    International Nuclear Information System (INIS)

    Kopsaftopoulos, Fotis P; Fassois, Spilios D

    2011-01-01

    A comparative assessment of several vibration based statistical time series methods for Structural Health Monitoring (SHM) is presented via their application to a scale aircraft skeleton laboratory structure. A brief overview of the methods, which are either scalar or vector type, non-parametric or parametric, and pertain to either the response-only or excitation-response cases, is provided. Damage diagnosis, including both the detection and identification subproblems, is tackled via scalar or vector vibration signals. The methods' effectiveness is assessed via repeated experiments under various damage scenarios, with each scenario corresponding to the loosening of one or more selected bolts. The results of the study confirm the 'global' damage detection capability and effectiveness of statistical time series methods for SHM.

  10. Violence, stigma and mental health among female sex workers in China: A structural equation modeling.

    Science.gov (United States)

    Zhang, Liying; Li, Xiaoming; Wang, Bo; Shen, Zhiyong; Zhou, Yuejiao; Xu, Jinping; Tang, Zhenzhu; Stanton, Bonita

    2017-07-01

    Intimate partner violence is prevalent among female sex workers (FSWs) in China, and it is significantly associated with mental health problems among FSWs. However, limited studies have explored the mechanisms/process by which violence affects mental health. The purpose of this study was to explore the relationships among partner violence, internalized stigma, and mental health problems among FSWs. Data were collected using a self-administered cross-sectional survey administered to 1,022 FSWs in the Guangxi Zhuang Autonomous Region (Guangxi), China during 2008-2009. We used structural equation modeling to test the hypothesized relationships. Results indicated that violence perpetrated by either stable sexual partners or clients was directly and positively associated with mental health problems. Violence also had an indirect relation to mental health problems through stigma. Results highlight the need for interventions on counseling and care for FSWs who have experienced violence and for interventions to increase FSWs' coping skills and empowerment strategies.

  11. India's Proposed Universal Health Coverage Policy: Evidence for Age Structure Transition Effect and Fiscal Sustainability.

    Science.gov (United States)

    Narayana, Muttur Ranganathan

    2016-12-01

    India's High Level Expert Group on Universal Health Coverage in 2011 recommended a universal, public-funded and national health coverage policy. As a plausible forward-looking macroeconomic reform in the health sector, this policy proposal on universal health coverage (UHC) needs to be evaluated for age structure transition effect and fiscal sustainability to strengthen its current design and future implementation. Macroeconomic analyses of the long-term implications of age structure transition and fiscal sustainability on India's proposed UHC policy. A new measure of age-specific UHC is developed by combining the age profile of public and private health consumption expenditure by using the National Transfer Accounts methodology. Different projections of age-specific public health expenditure are calculated over the period 2005-2100 to account for the age structure transition effect. The projections include changes in: (1) levels of the expenditure as gross domestic product grows, (2) levels and shape of the expenditure as gross domestic product grows and expenditure converges to that of developed countries (or convergence scenario) based on the Lee-Carter model of forecasting mortality rates, and (3) levels of the expenditure as India moves toward a UHC policy. Fiscal sustainability under each health expenditure projection is determined by using the measures of generational imbalance and sustainability gap in the Generational Accounting methodology. Public health expenditure is marked by age specificities and the elderly population is costlier to support for their healthcare needs in the future. Given the discount and productivity growth rates, the proposed UHC is not fiscally sustainable under India's current fiscal policies except for the convergence scenario. However, if the income elasticity of public expenditure on social welfare and health expenditure is less than one, fiscal sustainability of the UHC policy is attainable in all scenarios of projected public

  12. A Framework for Developing the Structure of Public Health Economic Models.

    Science.gov (United States)

    Squires, Hazel; Chilcott, James; Akehurst, Ronald; Burr, Jennifer; Kelly, Michael P

    2016-01-01

    A conceptual modeling framework is a methodology that assists modelers through the process of developing a model structure. Public health interventions tend to operate in dynamically complex systems. Modeling public health interventions requires broader considerations than clinical ones. Inappropriately simple models may lead to poor validity and credibility, resulting in suboptimal allocation of resources. This article presents the first conceptual modeling framework for public health economic evaluation. The framework presented here was informed by literature reviews of the key challenges in public health economic modeling and existing conceptual modeling frameworks; qualitative research to understand the experiences of modelers when developing public health economic models; and piloting a draft version of the framework. The conceptual modeling framework comprises four key principles of good practice and a proposed methodology. The key principles are that 1) a systems approach to modeling should be taken; 2) a documented understanding of the problem is imperative before and alongside developing and justifying the model structure; 3) strong communication with stakeholders and members of the team throughout model development is essential; and 4) a systematic consideration of the determinants of health is central to identifying the key impacts of public health interventions. The methodology consists of four phases: phase A, aligning the framework with the decision-making process; phase B, identifying relevant stakeholders; phase C, understanding the problem; and phase D, developing and justifying the model structure. Key areas for further research involve evaluation of the framework in diverse case studies and the development of methods for modeling individual and social behavior. This approach could improve the quality of Public Health economic models, supporting efficient allocation of scarce resources. Copyright © 2016 International Society for Pharmacoeconomics

  13. Hybrid optical-fibre/geopolymer sensors for structural health monitoring of concrete structures

    Science.gov (United States)

    Perry, M.; Saafi, M.; Fusiek, G.; Niewczas, P.

    2015-04-01

    In this work, we demonstrate hybrid optical-fibre/geopolymer sensors for monitoring temperature, uniaxial strain and biaxial strain in concrete structures. The hybrid sensors detect these measurands via changes in geopolymer electrical impedance, and via optical wavelength measurements of embedded fibre Bragg gratings. Electrical and optical measurements were both facilitated by metal-coated optical fibres, which provided the hybrid sensors with a single, shared physical path for both voltage and wavelength signals. The embedded fibre sensors revealed that geopolymer specimens undergo 2.7 mɛ of shrinkage after one week of curing at 42 °C. After curing, an axial 2 mɛ compression of the uniaxial hybrid sensor led to impedance and wavelength shifts of 7 × 10-2 and -2 × 10-4 respectively. The typical strain resolution in the uniaxial sensor was 100 μ \\varepsilon . The biaxial sensor was applied to the side of a concrete cylinder, which was then placed under 0.6 mɛ of axial, compressive strain. Fractional shifts in impedance and wavelength, used to monitor axial and circumferential strain, were 3 × 10-2 and 4 × 10-5 respectively. The biaxial sensor’s strain resolution was approximately 10 μ \\varepsilon in both directions. Due to several design flaws, the uniaxial hybrid sensor was unable to accurately measure ambient temperature changes. The biaxial sensor, however, successfully monitored local temperature changes with 0.5 °C resolution.

  14. Evaluation of Health Equity Impact of Structural Policies: Overview of Research Methods Used in the SOPHIE Project.

    Science.gov (United States)

    Kunst, Anton E

    2017-07-01

    This article briefly assesses the research methods that were applied in the SOPHIE project to evaluate the impact of structural policies on population health and health inequalities. The evaluation of structural policies is one of the key methodological challenges in today's public health. The experience in the SOPHIE project was that mixed methods are essential to identify, understand, and predict the health impact of structural policies. On the one hand, quantitative studies that included spatial comparisons or time trend analyses, preferably in a quasi-experimental design, showed that some structural policies were associated with improved population health and smaller health inequalities. On the other hand, qualitative studies, often inspired by realist approaches, were important to understand how these policies could have achieved the observed impact and why they would succeed in some settings but fail in others. This review ends with five recommendations for future studies that aim to evaluate, understand, and predict how health inequalities can be reduced through structural policies.

  15. Organization and Finance of China's Health Sector: Historical Antecedents for Macroeconomic Structural Adjustment.

    Science.gov (United States)

    Li, Hui; Hilsenrath, Peter

    2016-01-01

    China has exploded onto the world economy over the past few decades and is undergoing rapid transformation toward relatively more services. The health sector is an important part of this transition. This article provides a historical account of the development of health care in China since 1949. It also focuses on health insurance and macroeconomic structural adjustment to less saving and more consumption. In particular, the question of how health insurance impacts precautionary savings is considered. Multivariate analysis using data from 1990 to 2012 is employed. The household savings rate is the dependent variable in 3 models segmented for rural and urban populations. Independent variables include out-of-pocket health expenditures, health insurance payouts, housing expenditure, education expenditure, and consumption as a share of gross domestic product (GDP). Out-of-pocket health expenditures were positively correlated with household savings rates. But health insurance remains weak, and increased payouts by health insurers have not been associated with lower levels of household savings so far. Housing was positively correlated, whereas education had a negative association with savings rates. This latter finding was unexpected. Perhaps education is perceived as investment and a substitute for savings. China's shift toward a more service-oriented economy includes growing dependence on the health sector. Better health insurance is an important part of this evolution. The organization and finance of health care is integrally linked with macroeconomic policy in an environment constrained by prevailing institutional convention. Problems of agency relationships, professional hegemony, and special interest politics feature prominently, as they do elsewhere. China also has a dual approach to medicine relying heavily on providers of traditional Chinese medicine. Both of these segments will take part in China's evolution, adding another layer of complexity to policy. © The

  16. Development of Structural Health Monitoring System for pipes in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Eom, H. S.; Choi, Y. C.; Shin, S. H.; Youn, D. B.; Park, J. H.

    2010-01-01

    Structural health monitoring (SHM) has becoming an important issue in the maintenance of various structures such as large steel plates, vessels, and pipes in nuclear power plants. There are important factors to be considered in developing an SHM system. With consideration of these factors, we have developed a computerized multi-channel ultrasonic system that can handle array transducers and generate a high-power pulse for online SHM of the plates and pipes. The proposed system is compact but has all the necessary functions for SHM of important structure such as pipes and plates in a NPP

  17. The Role of Electronic Health Records in Structuring Nursing Handoff Communication and Maintaining Situation Awareness

    Science.gov (United States)

    Alghenaimi, Said

    2012-01-01

    In healthcare institutions, work must continue 24 hours a day, 7 days a week. A team of nurses is needed to provide around-the-clock patient care, and this process requires transfer of patient care responsibilities, a process known as a "handoff." The present study explored the role of electronic health records in structuring handoff…

  18. Characterization of Aircraft Structural Damage Using Guided Wave Based Finite Element Analysis for In-Flight Structural Health Management

    Science.gov (United States)

    Seshadri, Banavara R.; Krishnamurthy, Thiagarajan; Ross, Richard W.

    2016-01-01

    The development of multidisciplinary Integrated Vehicle Health Management (IVHM) tools will enable accurate detection, diagnosis and prognosis of damage under normal and adverse conditions during flight. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and structural damage conditions. A major concern is the growth of undetected damage/cracks due to fatigue and low velocity foreign object impact that can reach a critical size during flight, resulting in loss of control of the aircraft. To avoid unstable catastrophic propagation of damage during a flight, load levels must be maintained that are below the load-carrying capacity for damaged aircraft structures. Hence, a capability is needed for accurate real-time predictions of safe load carrying capacity for aircraft structures with complex damage configurations. In the present work, a procedure is developed that uses guided wave responses to interrogate damage. As the guided wave interacts with damage, the signal attenuates in some directions and reflects in others. This results in a difference in signal magnitude as well as phase shifts between signal responses for damaged and undamaged structures. Accurate estimation of damage size and location is made by evaluating the cumulative signal responses at various pre-selected sensor locations using a genetic algorithm (GA) based optimization procedure. The damage size and location is obtained by minimizing the difference between the reference responses and the responses obtained by wave propagation finite element analysis of different representative cracks, geometries and sizes.

  19. An Integrated Health Monitoring Method for Structural Fatigue Life Evaluation Using Limited Sensor Data

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2016-11-01

    Full Text Available A general framework for structural fatigue life evaluation under fatigue cyclic loading using limited sensor data is proposed in this paper. First, limited sensor data are measured from various sensors which are preset on the complex structure. Then the strain data at remote spots are used to obtain the strain responses at critical spots by the strain/stress reconstruction method based on empirical mode decomposition (REMD method. All the computations in this paper are directly performed in the time domain. After the local stress responses at critical spots are determined, fatigue life evaluation can be performed for structural health management and risk assessment. Fatigue life evaluation using the reconstructed stresses from remote strain gauge measurement data is also demonstrated with detailed error analysis. Following this, the proposed methodology is demonstrated using a three-dimensional frame structure and a simplified airfoil structure. Finally, several conclusions and future work are drawn based on the proposed study.

  20. Test-bed for the remote health monitoring system for bridge structures using FBG sensors

    Science.gov (United States)

    Lee, Chin-Hyung; Park, Ki-Tae; Joo, Bong-Chul; Hwang, Yoon-Koog

    2009-05-01

    This paper reports on test-bed for the long-term health monitoring system for bridge structures employing fiber Bragg grating (FBG) sensors, which is remotely accessible via the web, to provide real-time quantitative information on a bridge's response to live loading and environmental changes, and fast prediction of the structure's integrity. The sensors are attached on several locations of the structure and connected to a data acquisition system permanently installed onsite. The system can be accessed through remote communication using an optical cable network, through which the evaluation of the bridge behavior under live loading can be allowed at place far away from the field. Live structural data are transmitted continuously to the server computer at the central office. The server computer is connected securely to the internet, where data can be retrieved, processed and stored for the remote web-based health monitoring. Test-bed revealed that the remote health monitoring technology will enable practical, cost-effective, and reliable condition assessment and maintenance of bridge structures.

  1. Structure for prevention of health care-associated infections in Brazilian hospitals: A countrywide study.

    Science.gov (United States)

    Padoveze, Maria Clara; Fortaleza, Carlos Magno Castelo Branco; Kiffer, Carlos; Barth, Afonso Luís; Carneiro, Irna Carla do Rosário Souza; Giamberardino, Heloisa Ilhe Garcia; Rodrigues, Jorge Luiz Nobre; Santos Filho, Lauro; de Mello, Maria Júlia Gonçalves; Pereira, Milca Severino; Gontijo Filho, Paulo; Rocha, Mirza; de Medeiros, Eduardo Alexandrino Servolo; Pignatari, Antonio Carlos Campos

    2016-01-01

    Minimal structure is required for effective prevention of health care-associated infection (HAI). The objective of this study was to evaluate the structure for prevention of HAI in a sample of Brazilian hospitals. This was a cross-sectional study from hospitals in 5 Brazilian regions (n = 153; total beds: 13,983) classified according to the number of beds; 11 university hospitals were used as reference for comparison. Trained nurses carried out the evaluation by using structured forms previously validated. The evaluation of conformity index (CI) included elements of structure of the Health Care-Associated Prevention and Control Committee (HAIPCC), hand hygiene, sterilization, and laboratory of microbiology. The median CI for the HAIPCC varied from 0.55-0.94 among hospital categories. Hospitals with >200 beds had the worst ratio of beds to sinks (3.9; P hospitals with hospitals (3.3; P hospitals were more likely to have their own laboratory of microbiology than other hospitals. This study highlights the need for public health strategies aiming to improve the structure for HAI prevention in Brazilian hospitals. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  2. Imbalance between Goals and Organizational Structure in Primary Health Care in Iran- a Systematic Review.

    Science.gov (United States)

    Zanganeh Baygi, Mehdi; Seyedin, Hesam

    2013-07-01

    In recent years, the main focus of health sector reforms in Iran is the family physician and referral system plan. Fundamental changes in the goals and strategies, has increased the necessity of the need to reform the organizational structure. This study tries to review and summarize all cases about the organizational structure of Iran and its challenges in primary health care system. This study was a systematic review of published and grey literature. We searched the relevant databases, bibliography of related papers, and laws, using appropriate search strategies and key words. The CASP tool was used by two experts to evaluate the quality of retrieved papers and inconsistencies were resolved by discussion. After removal of duplicate citations, a total of 52 titles were identified through database searching, among which 30 met the inclusion criteria. Considering the research quality criteria, 14 papers were recognized qualified, which were categorized into two groups of: articles and policies. The results showed ineffectiveness of the current organizational structure at different level. The majority of the papers recommend performing reforms in the system because of changes in goals and strategies. Also, some suggest an appropriate information system to be designed in the current structures. Centralization and delegation process are the main discussions for the studies. Because of fundamental changes in goals and strategies, reforms in the organizational structure of primary health system in Iran especially in peripheral levels are highly recommended.

  3. Australia's private health insurance industry: structure, competition, regulation and role in a less than 'ideal world'.

    Science.gov (United States)

    Shamsullah, Ardel

    2011-02-01

    Australia's private health insurance funds have been prominent participants in the nation's health system for 60 years. Yet there is relatively little public awareness of the distinctive origins of the health funds, the uncharacteristic organisational nature of these commercial enterprises and the peculiarly regulated nature of their industry. The conventional corporate responsibility to shareholders was, until recently, completely irrelevant, and remains marginal to the sector. However, their purported answerability to contributors, styled as 'members', was always doubtful for most health funds. After a long period of remarkable stability in the sector, despite significant shifts in health funding policy, recent years have brought notable changes, with mergers, acquisitions and exits from the industry. The research is based on the detailed study of the private health funds, covering their history, organisational character and industry structure. It argues that the funds have always been divorced from the disciplines of the competitive market and generally have operated complacently within a system of comprehensive regulation and generous subsidy. The prospect of the private health funds enjoying an expanded role under a form of 'social insurance', as suggested by the National Health and Hospitals Reform Commission, is not supported.

  4. Going nuclear? Family structure and young women's health in India, 1992-2006.

    Science.gov (United States)

    Allendorf, Keera

    2013-06-01

    Scholars traditionally argued that industrialization, urbanization, and educational expansion lead to a decline in extended families and complementary rise in nuclear families. Some have suggested that such transitions are good for young married women because living in nuclear families benefits their health. However, extended families may also present advantages for young women's health that outweigh any disadvantages. Using the Indian National Family Health Survey, this article examines whether young married women living in nuclear families have better health than those in patrilocal extended families. It also examines whether young married women's living arrangements are changing over time and, if so, how such changes will affect their health. Results show that young married women living in nuclear families do not have better health than those in patrilocal extended families. Of eight health outcomes examined, only five differ significantly by family structure. Further, of the five outcomes that differ, four are patrilocal extended-family advantages and only one is a nuclear-family advantage. From 1992 to 2006, the percentage of young married women residing in nuclear families increased, although the majority remained in patrilocal extended families. This trend toward nuclear families will not benefit young women's health.

  5. Health Promotion Behavior of Chinese International Students in Korea Including Acculturation Factors: A Structural Equation Model.

    Science.gov (United States)

    Kim, Sun Jung; Yoo, Il Young

    2016-03-01

    The purpose of this study was to explain the health promotion behavior of Chinese international students in Korea using a structural equation model including acculturation factors. A survey using self-administered questionnaires was employed. Data were collected from 272 Chinese students who have resided in Korea for longer than 6 months. The data were analyzed using structural equation modeling. The p value of final model is .31. The fitness parameters of the final model such as goodness of fit index, adjusted goodness of fit index, normed fit index, non-normed fit index, and comparative fit index were more than .95. Root mean square of residual and root mean square error of approximation also met the criteria. Self-esteem, perceived health status, acculturative stress and acculturation level had direct effects on health promotion behavior of the participants and the model explained 30.0% of variance. The Chinese students in Korea with higher self-esteem, perceived health status, acculturation level, and lower acculturative stress reported higher health promotion behavior. The findings can be applied to develop health promotion strategies for this population. Copyright © 2016. Published by Elsevier B.V.

  6. Structural Health Monitoring Using Wireless Technologies: An Ambient Vibration Test on the Adolphe Bridge, Luxembourg City

    Directory of Open Access Journals (Sweden)

    Adrien Oth

    2012-01-01

    Full Text Available Major threats to bridges primarily consist of the aging of the structural elements, earthquake-induced shaking and standing waves generated by windstorms. The necessity of information on the state of health of structures in real-time, allowing for timely warnings in the case of damaging events, requires structural health monitoring (SHM systems that allow the risks of these threats to be mitigated. Here we present the results of a short-duration experiment carried out with low-cost wireless instruments for monitoring the vibration characteristics and dynamic properties of a strategic civil infrastructure, the Adolphe Bridge in Luxembourg City. The Adolphe Bridge is a masonry arch construction dating from 1903 and will undergo major renovation works in the upcoming years. Our experiment shows that a network of these wireless sensing units is well suited to monitor the vibration characteristics of such a historical arch bridge and hence represents a low-cost and efficient solution for SHM.

  7. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    John Reilly

    2018-03-01

    Full Text Available Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc. and generalized displacement (deflection, rotation, etc. to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature–deformation–displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i the range of raw temperatures on the structure, and (ii the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  8. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring.

    Science.gov (United States)

    Reilly, John; Glisic, Branko

    2018-03-01

    Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM) analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc.) and generalized displacement (deflection, rotation, etc.) to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature-deformation-displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i) the range of raw temperatures on the structure, and (ii) the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  9. FE-ANN based modeling of 3D simple reinforced concrete girders for objective structural health evaluation.

    Science.gov (United States)

    2017-06-01

    The structural deterioration of aging infrastructure systems and the costs of repairing these systems is an increasingly important issue worldwide. Structural health monitoring (SHM), most commonly visual inspection and condition rating, has proven t...

  10. Multi-sensor sheets based on large-area electronics for advanced structural health monitoring of civil infrastructure.

    Science.gov (United States)

    2014-09-01

    Structural Health Monitoring has a great potential to provide valuable information about the actual structural : condition and can help optimize the management activities. However, few eective and robust monitoring technology exist which hinders a...

  11. Uncertainty Quantification for Monitoring of Civil Structures from Vibration Measurements

    Science.gov (United States)

    Döhler, Michael; Mevel, Laurent

    2014-05-01

    Health Monitoring of civil structures can be performed by detecting changes in the modal parameters of a structure, or more directly in the measured vibration signals. For a continuous monitoring the excitation of a structure is usually ambient, thus unknown and assumed to be noise. Hence, all estimates from the vibration measurements are realizations of random variables with inherent uncertainty due to (unknown) process and measurement noise and finite data length. In this talk, a strategy for quantifying the uncertainties of modal parameter estimates from a subspace-based system identification approach is presented and the importance of uncertainty quantification in monitoring approaches is shown. Furthermore, a damage detection method is presented, which is based on the direct comparison of the measured vibration signals without estimating modal parameters, while taking the statistical uncertainty in the signals correctly into account. The usefulness of both strategies is illustrated on data from a progressive damage action on a prestressed concrete bridge. References E. Carden and P. Fanning. Vibration based condition monitoring: a review. Structural Health Monitoring, 3(4):355-377, 2004. M. Döhler and L. Mevel. Efficient multi-order uncertainty computation for stochastic subspace identification. Mechanical Systems and Signal Processing, 38(2):346-366, 2013. M. Döhler, L. Mevel, and F. Hille. Subspace-based damage detection under changes in the ambient excitation statistics. Mechanical Systems and Signal Processing, 45(1):207-224, 2014.

  12. Formal intervention in employee health: comparisons of the nature and structure of employee assistance programs and health promotion programs.

    Science.gov (United States)

    Roman, P M; Blum, T C

    1988-01-01

    Health promotion programs (HPP) and employee assistance programs (EAP) are compared in terms of their structure and process. Two common themes are extracted: a belief that both are beneficial to both employers and employees, and a sense of 'mission'. The technology of HPP and EAP are examined and compared. EAPs' stimulation from Federal funding is contrasted with the more indigenous roots of HPPs. Examination of empirical data comparing organizations with EAPs which have and have not adopted HPPs indicate the former tend to be somewhat more 'caring' toward employees. An examination of program ingredients indicates much greater commonality of structural and processual ingredients within EAPs as compared to HPPs. The extent to which each program type has become more 'populist' in orientation and the implications of these changes for program technology are considered. Finally the paper describes differences in program evaluation stemming from target group definitions in the two types of programs.

  13. [National health fund and morbidity-based risk structure equalization with focus on haemophilia].

    Science.gov (United States)

    König, T

    2010-11-01

    The Gesundheitsfonds (national health fund) was established in Germany on January 1st, 2009, in combination with the morbidity-based risk structure equalization (RSA) in order to manage the cash flow between the statutory health insurances. The RSA equalizes income differences due to the varying levels of contributory income of the members of a health insurance (basic wage totals) and expenditure differences due to varying distribution of morbidity risks across different health insurances, as well as the varying numbers of non-contributing insured family members. Additionally, insured persons are allocated to morbidity groups according to a classification model based upon diagnoses and prescriptions anticipating medical expenses in the subsequent year. Haemophilia falls, among 80 disease entities, in the morbidity group which generates the highest risk supplement. Matching of prescribed drugs with disease entities facilitates disease grading and improves the accuracy of risk supplements.

  14. Portuguese validation of the Short Health Anxiety Inventory: Factor structure, reliability, and factor invariance.

    Science.gov (United States)

    Morales, Alexandra; Reis, Sibília; Espada, José P; Orgilés, Mireia

    2016-09-01

    The Short Health Anxiety Inventory is a brief instrument to assess health anxiety widely used across countries; however, no validated version is available for Portuguese-speaking population. Factorial structure, reliability, and equivalency factor with the Spanish version were analyzed with Portuguese adolescents aged 14-18 years. A Portuguese adolescent cohort ( N = 629) and a comparative Spanish adolescent cohort ( N = 1502) were evaluated. The original two-factor version was the best fitting model for the Portuguese version. The reliability was excellent. Complete measurement invariance across both countries was supported. The Portuguese version of the Short Health Anxiety Inventory is a valid screening inventory to assess health anxiety in adolescents.

  15. Effect of structural animal health planning on antimicrobial use and animal health variables in conventional dairy farming in the Netherlands.

    Science.gov (United States)

    Speksnijder, David C; Graveland, Haitske; Eijck, Ineke A J M; Schepers, René W M; Heederik, Dick J J; Verheij, Theo J M; Wagenaar, Jaap A

    2017-06-01

    Widespread veterinary use of antimicrobials might contribute to the increasing burden of antimicrobial resistance. Despite many successful efforts to reduce veterinary antimicrobial use in the Netherlands, antimicrobial use on a substantial number of farms has remained relatively high over the past few years. Farm-specific solutions are required to further lower antimicrobial use on these farms. Reducing the burden of animal diseases at the farm level by means of a structured approach to animal health planning could be promising. This intervention study aimed to evaluate the main effects of an animal health planning program developed by an advisory team consisting of a dairy farmer, his veterinarian, and his feed adviser under the guidance of a professional facilitator. During an initial farm visit, the advisory team developed a farm-specific animal health planning program with support from the facilitator. After 1 yr, the effects of this program on animal health, production parameters, and antimicrobial use were evaluated and compared with control farms that did not have a facilitated animal health planning program. Antimicrobial use on intervention farms was significantly reduced between the start and the end of the study period; however, no significant differences in the rate of reduction between the intervention and control groups could be observed (-19% and -14%, respectively). Reduced antimicrobial use did not result in negative effects on animal health and production parameters during the study period in both groups. On intervention farms, a significant positive relationship was found between the percentage of completed action points at farm level and the percentage reduction in antimicrobial use. The level of compliance with action points and the quality of collaboration between farmer and advisers were positively associated with the accomplishment of corresponding objectives. However, the total number of objectives was negatively associated with the level

  16. Internet of Things (IoT Platform for Structure Health Monitoring

    Directory of Open Access Journals (Sweden)

    Ahmed Abdelgawad

    2017-01-01

    Full Text Available Increase in the demand for reliable structural health information led to the development of Structural Health Monitoring (SHM. Prediction of upcoming accidents and estimation of useful life span of a structure are facilitated through SHM. While data sensing is the core of any SHM, tracking the data anytime anywhere is a prevailing challenge. With the advancement in information technology, the concept of Internet of Things (IoT has made it possible to integrate SHM with Internet to track data anytime anywhere. In this paper, a SHM platform embedded with IoT is proposed to detect the size and location of damage in structures. The proposed platform consists of a Wi-Fi module, a Raspberry Pi, an Analog to Digital Converter (ADC, a Digital to Analog Converter (DAC, a buffer, and piezoelectric (PZT sensors. The piezoelectric sensors are mounted as a pair in the structure. Data collected from the piezoelectric sensors will be used to detect the size and location of damage using a proposed mathematical model. Implemented on a Raspberry Pi, the proposed mathematical model will estimate the size and location of structural damage, if any, and upload the data to Internet. This data will be stored and can be checked remotely from any mobile device. The system has been validated using a real test bed in the lab.

  17. Research of diagnosis sensors fault based on correlation analysis of the bridge structural health monitoring system

    Science.gov (United States)

    Hu, Shunren; Chen, Weimin; Liu, Lin; Gao, Xiaoxia

    2010-03-01

    Bridge structural health monitoring system is a typical multi-sensor measurement system due to the multi-parameters of bridge structure collected from the monitoring sites on the river-spanning bridges. Bridge structure monitored by multi-sensors is an entity, when subjected to external action; there will be different performances to different bridge structure parameters. Therefore, the data acquired by each sensor should exist countless correlation relation. However, complexity of the correlation relation is decided by complexity of bridge structure. Traditionally correlation analysis among monitoring sites is mainly considered from physical locations. unfortunately, this method is so simple that it cannot describe the correlation in detail. The paper analyzes the correlation among the bridge monitoring sites according to the bridge structural data, defines the correlation of bridge monitoring sites and describes its several forms, then integrating the correlative theory of data mining and signal system to establish the correlation model to describe the correlation among the bridge monitoring sites quantificationally. Finally, The Chongqing Mashangxi Yangtze river bridge health measurement system is regards as research object to diagnosis sensors fault, and simulation results verify the effectiveness of the designed method and theoretical discussions.

  18. STRUCTURAL AND HIDDEN BARRIERS TO A LOCAL PRIMARY HEALTH CARE INFRASTRUCTURE: AUTONOMY, DECISIONS ABOUT PRIMARY HEALTH CARE, AND THE CENTRALITY AND SIGNIFICANCE OF POWER.

    Science.gov (United States)

    Freed, Christopher R; Hansberry, Shantisha T; Arrieta, Martha I

    2013-09-01

    To examine a local primary health care infrastructure and the reality of primary health care from the perspective of residents of a small, urban community in the southern United States. Data derive from 13 semi-structured focus groups, plus three semi-structured interviews, and were analyzed inductively consistent with a grounded theory approach. Structural barriers to the local primary health care infrastructure include transportation, clinic and appointment wait time, and co-payments and health insurance. Hidden barriers consist of knowledge about local health care services, non-physician gatekeepers, and fear of medical care. Community residents have used home remedies and the emergency department at the local academic medical center to manage these structural and hidden barriers. Findings might not generalize to primary health care infrastructures in other communities, respondent perspectives can be biased, and the data are subject to various interpretations and conceptual and thematic frameworks. Nevertheless, the structural and hidden barriers to the local primary health care infrastructure have considerably diminished the autonomy community residents have been able to exercise over their decisions about primary health care, ultimately suggesting that efforts concerned with increasing the access of medically underserved groups to primary health care in local communities should recognize the centrality and significance of power. This study addresses a gap in the sociological literature regarding the impact of specific barriers to primary health care among medically underserved groups.

  19. Pediatric health-related quality of life: a structural equation modeling approach.

    Directory of Open Access Journals (Sweden)

    Ester Villalonga-Olives

    Full Text Available OBJECTIVES: One of the most referenced theoretical frameworks to measure Health Related Quality of Life (HRQoL is the Wilson and Cleary framework. With some adaptions this framework has been validated in the adult population, but has not been tested in pediatric populations. Our goal was to empirically investigate it in children. METHODS: The contributory factors to Health Related Quality of Life that we included were symptom status (presence of chronic disease or hospitalizations, functional status (developmental status, developmental aspects of the individual (social-emotional behavior, and characteristics of the social environment (socioeconomic status and area of education. Structural equation modeling was used to assess the measurement structure of the model in 214 German children (3-5 years old participating in a follow-up study that investigates pediatric health outcomes. RESULTS: Model fit was χ2 = 5.5; df = 6; p = 0.48; SRMR  = 0.01. The variance explained of Health Related Quality of Life was 15%. Health Related Quality of Life was affected by the area education (i.e. where kindergartens were located and development status. Developmental status was affected by the area of education, socioeconomic status and individual behavior. Symptoms did not affect the model. CONCLUSIONS: The goodness of fit and the overall variance explained were good. However, the results between children' and adults' tests differed and denote a conceptual gap between adult and children measures. Indeed, there is a lot of variety in pediatric Health Related Quality of Life measures, which represents a lack of a common definition of pediatric Health Related Quality of Life. We recommend that researchers invest time in the development of pediatric Health Related Quality of Life theory and theory based evaluations.

  20. Factor structure and internal reliability of an exercise health belief model scale in a Mexican population

    Directory of Open Access Journals (Sweden)

    Oscar Armando Esparza-Del Villar

    2017-03-01

    Full Text Available Abstract Background Mexico is one of the countries with the highest rates of overweight and obesity around the world, with 68.8% of men and 73% of women reporting both. This is a public health problem since there are several health related consequences of not exercising, like having cardiovascular diseases or some types of cancers. All of these problems can be prevented by promoting exercise, so it is important to evaluate models of health behaviors to achieve this goal. Among several models the Health Belief Model is one of the most studied models to promote health related behaviors. This study validates the first exercise scale based on the Health Belief Model (HBM in Mexicans with the objective of studying and analyzing this model in Mexico. Methods Items for the scale called the Exercise Health Belief Model Scale (EHBMS were developed by a health research team, then the items were applied to a sample of 746 participants, male and female, from five cities in Mexico. The factor structure of the items was analyzed with an exploratory factor analysis and the internal reliability with Cronbach’s alpha. Results The exploratory factor analysis reported the expected factor structure based in the HBM. The KMO index (0.92 and the Barlett’s sphericity test (p < 0.01 indicated an adequate and normally distributed sample. Items had adequate factor loadings, ranging from 0.31 to 0.92, and the internal consistencies of the factors were also acceptable, with alpha values ranging from 0.67 to 0.91. Conclusions The EHBMS is a validated scale that can be used to measure exercise based on the HBM in Mexican populations.

  1. A multilevel cross-lagged structural equation analysis for reciprocal relationship between social capital and health.

    Science.gov (United States)

    Yu, Ge; Sessions, John G; Fu, Yu; Wall, Martin

    2015-10-01

    We investigated the reciprocal relationship between individual social capital and perceived mental and physical health in the UK. Using data from the British Household Panel Survey from 1991 to 2008, we fitted cross-lagged structural equation models that include three indicators of social capital vis. social participation, social network, and loneliness. Given that multiple measurement points (level 1) are nested within individuals (level 2), we also applied a multilevel model to allow for residual variation in the outcomes at the occasion and individual levels. Controlling for gender, age, employment status, educational attainment, marital status, household wealth, and region, our analyses suggest that social participation predicts subsequent change in perceived mental health, and vice versa. However, whilst loneliness is found to be significantly related to perceived mental and physical health, reciprocal causality is not found for perceived mental health. Furthermore, we find evidence for reverse effects with both perceived mental and physical health appearing to be the dominant causal factor with respect to the prospective level of social network. Our findings thus shed further light on the importance of social participation and social inclusion in health promotion and aid the development of more effective public health policies in the UK. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Artificial immune pattern recognition for damage detection in structural health monitoring sensor networks

    Science.gov (United States)

    Chen, Bo; Zang, Chuanzhi

    2009-03-01

    This paper presents an artificial immune pattern recognition (AIPR) approach for the damage detection and classification in structures. An AIPR-based Structure Damage Classifier (AIPR-SDC) has been developed by mimicking immune recognition and learning mechanisms. The structure damage patterns are represented by feature vectors that are extracted from the structure's dynamic response measurements. The training process is designed based on the clonal selection principle in the immune system. The selective and adaptive features of the clonal selection algorithm allow the classifier to generate recognition feature vectors that are able to match the training data. In addition, the immune learning algorithm can learn and remember various data patterns by generating a set of memory cells that contains representative feature vectors for each class (pattern). The performance of the presented structure damage classifier has been validated using a benchmark structure proposed by the IASC-ASCE (International Association for Structural Control - American Society of Civil Engineers) Structural Health Monitoring Task Group. The validation results show a better classification success rate comparing to some of other classification algorithms.

  3. A framework for data compression and damage detection in structural health monitoring applied on a laboratory three-story structure

    Directory of Open Access Journals (Sweden)

    Manoel Afonso Pereira de Lima

    2016-09-01

    Full Text Available Structural Health Monitoring (SHM is an important technique used to preserve many types of structures in the short and long run, using sensor networks to continuously gather the desired data. However, this causes a strong impact in the data size to be stored and processed. A common solution to this is using compression algorithms, where the level of data compression should be adequate enough to allow the correct damage identification. In this work, we use the data sets from a laboratory three-story structure to evaluate the performance of common compression algorithms which, then, are combined with damage detection algorithms used in SHM. We also analyze how the use of Independent Component Analysis, a common technique to reduce noise in raw data, can assist the detection performance. The results showed that Piecewise Linear Histogram combined with Nonlinear PCA have the best trade-off between compression and detection for small error thresholds while Adaptive PCA with Principal Component Analysis perform better with higher values.

  4. [Financing of regional occupational health service centers: structure and financial criteria in years 2000-2001].

    Science.gov (United States)

    Rydlewska-Liszkowska, Izabela

    2003-01-01

    The rational planning and financing of occupational health services at the national level have to be based on an appropriate system of information about individual units and their financial status that could illustrate their financial administration. This is required not only in view of the internal needs of public money management, but also in view of the national health accounts. The major task in this regard is to assess the level and structure of financing to individual units and to check the soundness of criteria used in the process of supplying financial means. The results of such an analysis can be a valuable source of information for planning carried out also by the institutions which provide funds to cover the cost of tasks performed by individual units. The aim of the project implemented by the Nofer Institute of Occupational Medicine was to collect, process and analyze data on the level and structure of financing of provincial occupational medicine centers. In this paper, the objectives, methodology and analytical tools are discussed. The results and structural data on the level and structure of financing of regional occupational health services centers covering a two-year period are presented. At the same time, the criteria for allocating funds were identified, which made it possible to evaluate the situation and to propose new solutions.

  5. Health Assessment of Large Two Dimensional Structures Using Limited Information: Recent Advances

    Directory of Open Access Journals (Sweden)

    Ajoy Kumar Das

    2012-01-01

    Full Text Available Some recent advances of a recently developed structural health assessment procedure proposed by the research team at the University of Arizona, commonly known as generalized iterative least-squares extended Kalman filter with unknown input (GILS-EKF-UI are presented. The procedure is a finite elements-based time-domain system-identification technique. It can assess structural health at the element level using only limited number of noise-contaminated responses. With the help of examples, it is demonstrated that the structure can be excited by multiple loadings simultaneously. The method can identify defects in various stages of degradation in single or multiple members and also relatively less severe defect. The defective element(s need not be in the substructure, but the defect detection capability increases if the defect spot is close to the substructure. Two alternatives are suggested to locate defect spot more accurately within a defective element. The paper advances several areas of GILS-EKF-UI to assess health of large structural systems.

  6. Structure of health-enhancing behavior in adolescence: a latent-variable approach.

    Science.gov (United States)

    Donovan, J E; Jessor, R; Costa, F M

    1993-12-01

    The structure of the interrelations among a variety of health-enhancing behaviors was examined using structural equation modeling analyses of questionnaire data from 1,280 middle school students and 2,219 high school students. The health-enhancing behaviors included seat belt use, adequate hours of sleep, attention to healthy diet, adequate exercise, low sedentary behavior, and regular toothbrushing. In the middle school sample, all of the health-enhancing behaviors correlated significantly but modestly with each other, except for sleep with toothbrushing. In the high school sample, all but three of the 15 correlations among the behaviors were significant. The results further show that a single underlying factor can account for the modest correlations among these health-enhancing behaviors in both samples. The generality of the single-factor model was also established for male, female, White, Hispanic, and Black students at each school level. These findings provide some support for the existence of health-related lifestyles in adolescence.

  7. Bringing home the health humanities: narrative humility, structural competency, and engaged pedagogy.

    Science.gov (United States)

    Tsevat, Rebecca K; Sinha, Anoushka A; Gutierrez, Kevin J; DasGupta, Sayantani

    2015-11-01

    As health humanities programs grow and thrive across the country, encouraging medical students to read, write, and become more reflective about their professional roles, educators must bring a sense of self-reflexivity to the discipline itself. In the health humanities, novels, patient histories, and pieces of reflective writing are often treated as architectural spaces or "homes" that one can enter and examine. Yet, narrative-based learning in health care settings does not always allow its participants to feel "at home"; when not taught with a critical attention to power and pedagogy, the health humanities can be unsettling and even dangerous. Educators can mitigate these risks by considering not only what they teach but also how they teach it.In this essay, the authors present three pedagogical pillars that educators can use to invite learners to engage more fully, develop critical awareness of medical narratives, and feel "at home" in the health humanities. These pedagogical pillars are narrative humility (an awareness of one's prejudices, expectations, and frames of listening), structural competency (attention to sources of power and privilege), and engaged pedagogy (the protection of students' security and well-being). Incorporating these concepts into pedagogical practices can create safe and productive classroom spaces for all, including those most vulnerable and at risk of being "unhomed" by conventional hierarchies and oppressive social structures. This model then can be translated through a parallel process from classroom to clinic, such that empowered, engaged, and cared-for learners become empowering, engaging, and caring clinicians.

  8. The Sociological Study of the Effect of Family Structure on Social Health of Males

    Directory of Open Access Journals (Sweden)

    Naima Mohammadi

    Full Text Available Social health depends on different social and cultural factors. One of the most important suppliers of individual’s health is family structures and relations. In recent years due to functional changes in polygamous structure, there are threats against social health of men in Sarbaz city. In this research, to compare the rate of social health of men in polygamous and monogamous families in Sarbaz city we use a standard questionnaire of Shapiro & Keyes (2007. The population of this study consisted of 300 males who are residents of this city. They selected by using cluster sampling method. Gathered data were analyzed using SPSS software version 22. Findings from independent T-Test revealed that the average of social Coherence, Integration, Contribution and Actualization between men in polygamous families were significantly lower than monogamous. Based on these findings, we can conclude however a lot of traditional social customs were useful, functional and compatible and provide social acceptance, but today have become dysfunctional and threated social health of family members and community system face with crisis.

  9. A Spray-On Carbon Nanotube Artificial Neuron Strain Sensor for Composite Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Gyeongrak Choi

    2016-07-01

    Full Text Available We present a nanocomposite strain sensor (NCSS to develop a novel structural health monitoring (SHM sensor that can be easily installed in a composite structure. An NCSS made of a multi-walled carbon nanotubes (MWCNT/epoxy composite was installed on a target structure with facile processing. We attempted to evaluate the NCSS sensing characteristics and benchmark compared to those of a conventional foil strain gauge. The response of the NCSS was fairly good and the result was nearly identical to the strain gauge. A neuron, which is a biomimetic long continuous NCSS, was also developed, and its vibration response was investigated for structural damage detection of a composite cantilever. The vibration response for damage detection was measured by tracking the first natural frequency, which demonstrated good result that matched the finite element (FE analysis.

  10. Structural Health Monitoring of Railway Transition Zones Using Satellite Radar Data.

    Science.gov (United States)

    Wang, Haoyu; Chang, Ling; Markine, Valeri

    2018-01-31

    Transition zones in railway tracks are locations with considerable changes in the rail-supporting structure. Typically, they are located near engineering structures, such as bridges, culverts and tunnels. In such locations, severe differential settlements often occur due to the different material properties and structure behavior. Without timely maintenance, the differential settlement may lead to the damage of track components and loss of passenger's comfort. To ensure the safety of railway operations and reduce the maintenance costs, it is necessary to consecutively monitor the structural health condition of the transition zones in an economical manner and detect the changes at an early stage. However, using the current in situ monitoring of transition zones is hard to achieve this goal, because most in situ techniques (e.g., track-measuring coaches) are labor-consuming and usually not frequently performed (approximately twice a year in the Netherlands). To tackle the limitations of the in situ techniques, a Satellite Synthetic Aperture Radar (InSAR) system is presented in this paper, which provides a potential solution for a consecutive structural health monitoring of transition zones with bi-/tri-weekly data update and mm-level precision. To demonstrate the feasibility of the InSAR system for monitoring transition zones, a transition zone is tested. The results show that the differential settlement in the transition zone and the settlement rate can be observed and detected by the InSAR measurements. Moreover, the InSAR results are cross-validated against measurements obtained using a measuring coach and a Digital Image Correlation (DIC) device. The results of the three measuring techniques show a good correlation, which proves the applicability of InSAR for the structural health monitoring of transition zones in railway track.

  11. Structural Health Monitoring of Railway Transition Zones Using Satellite Radar Data

    Directory of Open Access Journals (Sweden)

    Haoyu Wang

    2018-01-01

    Full Text Available Transition zones in railway tracks are locations with considerable changes in the rail-supporting structure. Typically, they are located near engineering structures, such as bridges, culverts and tunnels. In such locations, severe differential settlements often occur due to the different material properties and structure behavior. Without timely maintenance, the differential settlement may lead to the damage of track components and loss of passenger’s comfort. To ensure the safety of railway operations and reduce the maintenance costs, it is necessary to consecutively monitor the structural health condition of the transition zones in an economical manner and detect the changes at an early stage. However, using the current in situ monitoring of transition zones is hard to achieve this goal, because most in situ techniques (e.g., track-measuring coaches are labor-consuming and usually not frequently performed (approximately twice a year in the Netherlands. To tackle the limitations of the in situ techniques, a Satellite Synthetic Aperture Radar (InSAR system is presented in this paper, which provides a potential solution for a consecutive structural health monitoring of transition zones with bi-/tri-weekly data update and mm-level precision. To demonstrate the feasibility of the InSAR system for monitoring transition zones, a transition zone is tested. The results show that the differential settlement in the transition zone and the settlement rate can be observed and detected by the InSAR measurements. Moreover, the InSAR results are cross-validated against measurements obtained using a measuring coach and a Digital Image Correlation (DIC device. The results of the three measuring techniques show a good correlation, which proves the applicability of InSAR for the structural health monitoring of transition zones in railway track.

  12. Health monitoring and rehabilitation of a concrete structure using intelligent materials

    Science.gov (United States)

    Song, G.; Mo, Y. L.; Otero, K.; Gu, H.

    2006-04-01

    This paper presents the concept of an intelligent reinforced concrete structure (IRCS) and its application in structural health monitoring and rehabilitation. The IRCS has multiple functions which include self-rehabilitation, self-vibration damping, and self-structural health monitoring. These functions are enabled by two types of intelligent (smart) materials: shape memory alloys (SMAs) and piezoceramics. In this research, Nitinol type SMA and PZT (lead zirconate titanate) type piezoceramics are used. The proposed concrete structure is reinforced by martensite Nitinol cables using the method of post-tensioning. The martensite SMA significantly increases the concrete's damping property and its ability to handle large impact. In the presence of cracks due to explosions or earthquakes, by electrically heating the SMA cables, the SMA cables contract and close up the cracks. In this research, PZT patches are embedded in the concrete structure to detect possible cracks inside the concrete structure. The wavelet packet analysis method is then applied as a signal-processing tool to analyze the sensor signals. A damage index is defined to describe the damage severity for health monitoring purposes. In addition, by monitoring the electric resistance change of the SMA cables, the crack width can be estimated. To demonstrate this concept, a concrete beam specimen with reinforced SMA cables and with embedded PZT patches is fabricated. Experiments demonstrate that the IRC has the ability of self-sensing and self-rehabilitation. Three-point bending tests were conducted. During the loading process, a crack opens up to 0.47 inches. Upon removal of the load and heating the SMA cables, the crack closes up. The damage index formed by wavelet packet analysis of the PZT sensor data predicts and confirms the onset and severity of the crack during the loading. Also during the loading, the electrical resistance value of the SMA cable changes by up to 27% and this phenomenon is used to

  13. Structural Stigma and Health Inequalities: Research Evidence and Implications for Psychological Science

    Science.gov (United States)

    Hatzenbuehler, Mark L.

    2016-01-01

    Psychological research has provided essential insights into how stigma operates to disadvantage those who are targeted by it. At the same time, stigma research has been criticized for being too focused on the perceptions of stigmatized individuals and on micro-level interactions, rather than attending to structural forms of stigma. This article describes the relatively new field of research on structural stigma, which is defined as societal-level conditions, cultural norms, and institutional policies that constrain the opportunities, resources, and wellbeing of the stigmatized. I review emerging evidence that structural stigma related to mental illness and sexual orientation (1) exerts direct and synergistic effects on stigma processes that have long been the focus of psychological inquiry (e.g., concealment, rejection sensitivity); (2) serves as a contextual moderator of the efficacy of psychological interventions; and (3) contributes to numerous adverse health outcomes for members of stigmatized groups—ranging from dysregulated physiological stress responses to premature mortality—indicating that structural stigma represents an under-recognized mechanism producing health inequalities. Each of these pieces of evidence suggests that structural stigma is relevant to psychology and therefore deserves the attention of psychological scientists interested in understanding and ultimately reducing the negative effects of stigma. PMID:27977256

  14. A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

    Science.gov (United States)

    Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

    2010-01-01

    During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use. PMID:22399929

  15. A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

    Directory of Open Access Journals (Sweden)

    Yaowen Yang

    2010-05-01

    Full Text Available During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

  16. A reusable PZT transducer for monitoring initial hydration and structural health of concrete.

    Science.gov (United States)

    Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

    2010-01-01

    During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

  17. [Relationship between organisational structure and worksite health management in the information technology and communications sector].

    Science.gov (United States)

    Ansmann, L; Jung, J; Nitzsche, A; Pfaff, H

    2012-05-01

    Worksite health management (WHM) can positively influence employee health and performance. However, it has not yet been comprehensively implemented in companies. This study aims to identify the role of organisational structures in the implementation of WHM. In this cross-sectional study, data were collected on the companies' WHM and the organisational structure. Out of 522 randomly selected companies within the German information technology and communication (ITC) sector, one managing director for each company was being questioned through telephone interviews. Bivariate and multivariate logistic regression analyses were conducted. The results of the study reveal that the implementation of WHM is positively correlated with a large company size (OR 2.75; 95%-CI 1.10-6.88) and with the existence of an employee representation (OR 2.48; 95%-CI 1.54-3.98). Other structural characteristics, such as the employment of a company physician, the percentage of temporary workers as well as the staff's age and sex distribution do not seem to have a significant impact on the implementation of WHM. The results indicate that the implementation of WHM can only be explained to a certain degree by organisational structures. However, the findings highlight the fact that companies with few structural resources are in particular need of tailored support when implementing WHM. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Value of information: A roadmap to quantifying the benefit of structural health monitoring

    DEFF Research Database (Denmark)

    Straub, D.; Chatzi, E.; Bismut, E.

    2017-01-01

    The concept of value of information (VoI) enables quantification of the benefits provided by structural health monitoring (SHM) systems – in principle. Its implementation is challenging, as it requires an explicit modelling of the structural system’s life cycle, in particular of the decisions...... that are taken based on the SHM information. In this paper, we approach the VoI analysis through an influence diagram (ID), which supports the modelling process. We provide a simple example for illustration and discuss challenges associated with real-life implementation....

  19. The impact of family structure on the health of children: Effects of divorce.

    Science.gov (United States)

    Anderson, Jane

    2014-11-01

    Nearly three decades of research evaluating the impact of family structure on the health and well-being of children demonstrates that children living with their married, biological parents consistently have better physical, emotional, and academic well-being. Pediatricians and society should promote the family structure that has the best chance of producing healthy children. The best scientific literature to date suggests that, with the exception of parents faced with unresolvable marital violence, children fare better when parents work at maintaining the marriage. Consequently, society should make every effort to support healthy marriages and to discourage married couples from divorcing.

  20. Structural health monitoring tools for late and end of life management of offshore wind turbines

    DEFF Research Database (Denmark)

    McGugan, Malcolm; McKirdy, Scott

    2016-01-01

    The late and end of life stages in an offshore wind turbines (OWT) life cycle have unique features that must be considered. The initial focus on risks associated with start-up issues due to design, manufacturing or process elements gives way to a stable period of operation and maintenance...... margins and the predominance of low redundancy structures, accurate structural health monitoring can play a strong role in safe management and enable increased operating time at end of life and decommissioning. Late life operations of offshore wind farms can pose significant challenges, balancing...

  1. [The current and future organisational structure of the OIE (World Organisation for Animal Health)].

    Science.gov (United States)

    Crespo León, F; Ruiz Mercader, J; Sabater Sánchez, R; Rodríguez Ferri, E F; Crespo Azofra, L

    2003-12-01

    The authors analyse the organisational structure of the OIE (World organisation for animal health), highlighting the roles of the Central Bureau, the Specialist Commissions, Regional Commissions, working groups and ad hoc groups, Regional Representations, Reference Laboratories and Collaborating Centres. The paper also includes some suggestions as to how the OIE could work more closely with its 'customers', that is, the Member Countries. These suggestions are based on current theories of organisational flexibility, and take into account not only the current organisational structure of the OIE, but also the Strategic Plan and the Working Plan, which were adopted at the 69th General Session of the OIE International Committee in 2001.

  2. TLP Structural Health Monitoring Based on Vibration Signal of Energy Harvesting System

    Directory of Open Access Journals (Sweden)

    Vahid Jahangiri

    Full Text Available Abstract Structural Health Monitoring (SHM of Tension Leg Platform (TLP is very crucial for preventing catastrophic and sudden collapse of the structures. One of the methods of monitoring these structures is implementing SHM sensors. Supplying energy for these sensors for a long period is a challenging problem. So, one of the new methods of supplying energy for SHM, is usage of mechanical energy. In this method, the piezoelectric material is employed to convert the mechanical energy which is resulted from vibration of structure, to electrical energy. The advantage of this method is based on not implementing the battery charging system. Therefore, in this paper, after modeling TLP structure, energy supplying of these sensors with piezoelectric converters is studied. Furthermore, fault diagnosis of these structures in the presence of different uncertainties is proposed by the features of voltage signal, produced from piezoelectric patches and fuzzy classification method. Results show that this method can diagnose faults of the structure with an acceptable success rate.

  3. The cross-national structure of mental disorders: results from the World Mental Health Surveys.

    Science.gov (United States)

    de Jonge, Peter; Wardenaar, Klaas J; Lim, Carmen C W; Aguilar-Gaxiola, Sergio; Alonso, Jordi; Andrade, Laura Helena; Bunting, Brendan; Chatterji, Somnath; Ciutan, Marius; Gureje, Oye; Karam, Elie G; Lee, Sing; Medina-Mora, Maria Elena; Moskalewicz, Jacek; Navarro-Mateu, Fernando; Pennell, Beth-Ellen; Piazza, Marina; Posada-Villa, José; Torres, Yolanda; Kessler, Ronald C; Scott, Kate

    2017-12-19

    The patterns of comorbidity among mental disorders have led researchers to model the underlying structure of psychopathology. While studies have suggested a structure including internalizing and externalizing disorders, less is known with regard to the cross-national stability of this model. Moreover, little data are available on the placement of eating disorders, bipolar disorder and psychotic experiences (PEs) in this structure. We evaluated the structure of mental disorders with data from the World Health Organization Composite International Diagnostic Interview, including 15 lifetime mental disorders and six PEs. Respondents (n = 5478-15 499) were included from 10 high-, middle- and lower middle-income countries across the world aged 18 years or older. Confirmatory factor analyses (CFAs) were used to evaluate and compare the fit of different factor structures to the lifetime disorder data. Measurement invariance was evaluated with multigroup CFA (MG-CFA). A second-order model with internalizing and externalizing factors and fear and distress subfactors best described the structure of common mental disorders. MG-CFA showed that this model was stable across countries. Of the uncommon disorders, bipolar disorder and eating disorder were best grouped with the internalizing factor, and PEs with a separate factor. These results indicate that cross-national patterns of lifetime common mental-disorder comorbidity can be explained with a second-order underlying structure that is stable across countries and can be extended to also cover less common mental disorders.

  4. Coupling Sensing Hardware with Data Interrogation Software for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Charles R. Farrar

    2006-01-01

    Full Text Available The process of implementing a damage detection strategy for aerospace, civil and mechanical engineering infrastructure is referred to as structural health monitoring (SHM. The authors' approach is to address the SHM problem in the context of a statistical pattern recognition paradigm. In this paradigm, the process can be broken down into four parts: (1 Operational Evaluation, (2 Data Acquisition and Cleansing, (3 Feature Extraction and Data Compression, and (4 Statistical Model Development for Feature Discrimination. These processes must be implemented through hardware or software and, in general, some combination of these two approaches will be used. This paper will discuss each portion of the SHM process with particular emphasis on the coupling of a general purpose data interrogation software package for structural health monitoring with a modular wireless sensing and processing platform. More specifically, this paper will address the need to take an integrated hardware/software approach to developing SHM solutions.

  5. Moire-Fringe-Based Fiber Optic Tiltmeter for Structural Health Monitoring

    International Nuclear Information System (INIS)

    Kim, Dae Hyun

    2008-01-01

    This paper presents a novel fiber optic tiltmeter system for the health monitoring of large-size structures. The system is composed of a sensor head, a light control unit and a signal processing unit. The sensing mechanism of the sensor head is based on a novel integration of the moire fringe phenomenon with fiber optics to achieve a robust performance in addition to its immunity to EM interference, easy ratting, and low cost. In this paper, a prototype of the fiber optic tiltmeter system has been developed successfully. A low-cost light control unit has been developed to drive the system's optic and electronic components. From an experimental test, the fiber optic tiltmeter is proven to be a prospective sensor for the monitoring of the tilting angle of civil structure with a good linearity. Finally, the test also successfully demonstrates the performance and the potential of the novel fiber optic tiltmeter system to monitor the health of civil infrastructures.

  6. Sensor-Only System Identification for Structural Health Monitoring of Advanced Aircraft

    Science.gov (United States)

    Kukreja, Sunil L.; Bernstein, Dennis S.

    2012-01-01

    Environmental conditions, cyclic loading, and aging contribute to structural wear and degradation, and thus potentially catastrophic events. The challenge of health monitoring technology is to determine incipient changes accurately and efficiently. This project addresses this challenge by developing health monitoring techniques that depend only on sensor measurements. Since actively controlled excitation is not needed, sensor-to-sensor identification (S2SID) provides an in-flight diagnostic tool that exploits ambient excitation to provide advance warning of significant changes. S2SID can subsequently be followed up by ground testing to localize and quantify structural changes. The conceptual foundation of S2SID is the notion of a pseudo-transfer function, where one sensor is viewed as the pseudo-input and another is viewed as the pseudo-output, is approach is less restrictive than transmissibility identification and operational modal analysis since no assumption is made about the locations of the sensors relative to the excitation.

  7. Structural Intervention With School Nurses Increases Receipt of Sexual Health Care Among Male High School Students.

    Science.gov (United States)

    Dittus, Patricia J; Harper, Christopher R; Becasen, Jeffrey S; Donatello, Robin A; Ethier, Kathleen A

    2018-01-01

    Adolescent males are less likely to receive health care and have lower levels of sexual and reproductive health (SRH) knowledge than adolescent females. The purpose of this study was to determine if a school-based structural intervention focused on school nurses increases receipt of condoms and SRH information among male students. Interventions to improve student access to sexual and reproductive health care were implemented in six urban high schools with a matched set of comparison schools. Interventions included working with school nurses to improve access to sexual and reproductive health care, including the provision of condoms and information about pregnancy and sexually transmitted disease prevention and services. Intervention effects were assessed through five cross-sectional yearly surveys, and analyses include data from 13,740 male students. Nurses in intervention schools changed their interactions with male students who visited them for services, such that, among those who reported they went to the school nurse for any reason in the previous year, those in intervention schools reported significant increases in receipt of sexual health services over the course of the study compared with students in comparison schools. Further, these results translated into population-level effects. Among all male students surveyed, those in intervention schools were more likely than those in comparison schools to report increases in receipt of sexual health services from school nurses. With a minimal investment of resources, school nurses can become important sources of SRH information and condoms for male high school students. Published by Elsevier Inc.

  8. XML and its impact on content and structure in electronic health care documents.

    Science.gov (United States)

    Sokolowski, R.; Dudeck, J.

    1999-01-01

    Worldwide information networks have the requirement that electronic documents must be easily accessible, portable, flexible and system-independent. With the development of XML (eXtensible Markup Language), the future of electronic documents, health care informatics and the Web itself are about to change. The intent of the recently formed ASTM E31.25 subcommittee, "XML DTDs for Health Care", is to develop standard electronic document representations of paper-based health care documents and forms. A goal of the subcommittee is to work together to enhance existing levels of interoperability among the various XML/SGML standardization efforts, products and systems in health care. The ASTM E31.25 subcommittee uses common practices and software standards to develop the implementation recommendations for XML documents in health care. The implementation recommendations are being developed to standardize the many different structures of documents. These recommendations are in the form of a set of standard DTDs, or document type definitions that match the electronic document requirements in the health care industry. This paper discusses recent efforts of the ASTM E31.25 subcommittee. PMID:10566338

  9. Development of a structural health monitoring system for the life assessment of critical transportation infrastructure.

    Energy Technology Data Exchange (ETDEWEB)

    Roach, Dennis Patrick; Jauregui, David Villegas (New Mexico State University, Las Cruces, NM); Daumueller, Andrew Nicholas (New Mexico State University, Las Cruces, NM)

    2012-02-01

    Recent structural failures such as the I-35W Mississippi River Bridge in Minnesota have underscored the urgent need for improved methods and procedures for evaluating our aging transportation infrastructure. This research seeks to develop a basis for a Structural Health Monitoring (SHM) system to provide quantitative information related to the structural integrity of metallic structures to make appropriate management decisions and ensuring public safety. This research employs advanced structural analysis and nondestructive testing (NDT) methods for an accurate fatigue analysis. Metal railroad bridges in New Mexico will be the focus since many of these structures are over 100 years old and classified as fracture-critical. The term fracture-critical indicates that failure of a single component may result in complete collapse of the structure such as the one experienced by the I-35W Bridge. Failure may originate from sources such as loss of section due to corrosion or cracking caused by fatigue loading. Because standard inspection practice is primarily visual, these types of defects can go undetected due to oversight, lack of access to critical areas, or, in riveted members, hidden defects that are beneath fasteners or connection angles. Another issue is that it is difficult to determine the fatigue damage that a structure has experienced and the rate at which damage is accumulating due to uncertain history and load distribution in supporting members. A SHM system has several advantages that can overcome these limitations. SHM allows critical areas of the structure to be monitored more quantitatively under actual loading. The research needed to apply SHM to metallic structures was performed and a case study was carried out to show the potential of SHM-driven fatigue evaluation to assess the condition of critical transportation infrastructure and to guide inspectors to potential problem areas. This project combines the expertise in transportation infrastructure at New

  10. Bayesian updating and decision making using correlated structural health monitoring observations

    DEFF Research Database (Denmark)

    Nielsen, Jannie Sønderkær

    2018-01-01

    A Bayesian approach is often applied when updating a deterioration model using observations from expected structural health monitoring or condition monitoring. Usually, observations are assumed to be independent conditioned on the damage size, but this assumption does not always hold, especially ...... is properly modeled. In case of correlated observations, an advanced decision model using all past observations for decision making is needed to make monitoring feasible compared to only using inspections....

  11. Structuring Health in Colorectal Cancer Screening Conversations: An Analysis of Intersecting Activity Systems

    OpenAIRE

    Canary, Heather; Bullis, Connie; Cummings, Jennifer; Kinney, Anita Y.

    2015-01-01

    This study used structurating activity theory to analyze 21 conversations between genetic counselors and individuals at increased risk for familial colorectal cancer (CRC). The qualitative analysis revealed ways elements of family, primary healthcare, cancer prevention and treatment, and other systems emerged in intervention conversations as shaping CRC screening attitudes and behaviors. Results indicate that family stories, norms, and roles are resources for enacting health practices in fami...

  12. A multilevel cross-lagged structural equation analysis for reciprocal relationship between social capital and health

    OpenAIRE

    Sessions, John; Yu, Ge; Fu, Yu; Wall, Matin

    2015-01-01

    We investigated the reciprocal relationship between individual social capital and perceived mental and physical health in the UK. Using data from the British Household Panel Survey from 1991 to 2008, we fitted cross-lagged structural equation models that include three indicators of social capital vis. social participation, social network, and loneliness. Given that multiple measurement points (level 1) are nested within individuals (level 2), we also applied a multilevel model to allow for re...

  13. The nature and structure of supervision in health visiting with victims of child sexual abuse.

    Science.gov (United States)

    Scott, L

    1999-03-01

    Part of a higher research degree to explore professional practice. To explore how health visitors work with victims of child sexual abuse and the supervision systems to support them. To seek the views and experiences of practising health visitors relating to complex care in order to consider the nature and structure of supervision. The research reported in this paper used a qualitative method of research and semi-structured interviews with practising health visitors of varying levels of experience in venues around England. Qualitative research enabled the exploration of experiences. Identification of the need for regular, structured, accountable opportunities in a 'private setting' to discuss whole caseload work and current practice issues. Supervision requires a structured, formalized process, in both regularity and content, as a means to explore and acknowledge work with increasingly complex care, to enable full discussion of whole caseloads. Supervision is demonstrated as a vehicle to enable the sharing of good practices and for weak practices to be identified and managed appropriately. Supervision seeks to fulfil the above whilst promoting a stimulating, learning experience, accommodating the notion that individuals learn at their own pace and bring a wealth of human experience to the service. The size of the study was dictated by the amount of time available within which to complete a research master's degree course primarily in the author's own time, over a 2-year period. The majority of participants volunteered their accounts in their own time. For others I obtained permission from their employers for them to participate once they approached me with an interest in being interviewed. This research provides a model of supervision based on practitioner views and experiences. The article highlights the value of research and evidence-based information to enhance practice accountability and the quality of care. Proactive risk management can safeguard the health

  14. The structure of occupational health nurses' support for return-to-work to workers with depression.

    Science.gov (United States)

    Hatanaka, Junko

    2016-07-29

    The present study aimed to explore the structure of occupational health nurses' support for return-to-work to workers with depression. Semi-structured interviews were conducted with 10 occupational health nurses who support workers returning to work. Data were analyzed using the Modified Grounded Theory Approach. The qualitatively analyzed data was grouped into 9 categories. The support for return-to-work was divided into 3 periods: (1) the first priority for recovery, (2) preparation for return-to-work, and (3) adaptation to work. There were indirect supports to workers such as "environmental arrangement for medical treatment," "connection," and "support form parties concerned about workers," and direct supports such as "readiness for medical treatment," "overcoming social and psychological problems," and "working life independence. " Direct support was facilitated by "construction of the relationship. " The occupational health nurses' philosophy was to support "profitable return-to-work for both the worker and the employer. " These processes were "support of confidence recovery process " to regain confidence lost through absence from work because of depression and to accomplish a smooth return-to-work. There were problems in each period corresponding to the return-to-work conditions, and occupational health nurses supported the employees in overcoming each problem. Moreover, it was said that cooperation with the parties concerned in the office would greatly influence the success or failure in the return-to-work support, and it was thought that direct supports and indirect supports to employees with respect to adjustment with the parties concerned in the office were necessary. The structure of occupational health nurses' supports was to support the confidence recovery process of workers by indirect and direct support at each period of return-to-work.

  15. Fatigue evaluation for Tsing Ma Bridge using structural health monitoring data

    Science.gov (United States)

    Chan, Hung-tin Tommy; Ko, Jan Ming; Li, Zhao-Xia

    2001-08-01

    Fatigue assessment for the Tsing Ma Bridge (TMB) are presented based on the British standard BS5400 and the real-time structural health monitoring data under railway loading. TMB, as an essential portion of transport network for the Hong Kong airport, is the longest suspension bridge in the world carrying both highway and railway traffic. The bridge design has been mainly based on BS5400. A structural health monitoring system - Wind and Structural Health Monitoring System (WASHMS) for TMB has been operated since the bridge commissioning in May 1997. In order to assess the fatigue behavior of TMB under railway loading, strain gauges were installed on the bridge deck to measure the strain-time histories as soon as the bridge is loaded by a standard railway loading due to the service of an actual train. The strain-time history data at the critical members are then used to determine the stress spectrum, of which the rainflow method recommended for railway bridges by BS5400 is applied to count cycles of stress range. Miner's law is employed to evaluate fatigue damage and remaining service life of the bridge. The evaluated results of fatigue damage and remaining service life would help us to well understand about the fatigue design of the bridge and status in fatigue accumulation.

  16. User involvement in structured violence risk management within forensic mental health facilities -- a systematic literature review.

    Science.gov (United States)

    Eidhammer, Gunnar; Fluttert, Frans A J; Bjørkly, Stål

    2014-10-01

    To examine empirical literature on user involvement in collaboration between patients and nurses. The scope of the review was limited to structured violence risk management interventions in forensic mental health settings. Violence in forensic mental health settings represents a significant problem for patients and staff. Structured violence risk management interventions in forensic mental health have been reported to ignore patient participation, despite the growing attention on user involvement in clinical practice. A systematic review. Searches were conducted in six databases: the Cochrane Systematic Reviews, MEDLINE, CINAHL, ProQuest, ScienceDirect and PsycINFO. Papers were assessed according to a predetermined set of inclusion and exclusion criteria. After searches of the reference lists of retrieved articles were conducted, only three papers met the inclusion criteria. This review has shown that empirical research on the topic of risk management interventions in which patients are involved is scarce. There is barely any research evidence of the clinical effect of user involvement approaches on violence risk management in forensic mental health practice. Therefore, we suggest that clinicians may learn from positive experiences concerning user involvement in general psychiatry and carefully adapt and test them out in the forensic treatment context. © 2014 John Wiley & Sons Ltd.

  17. Structural health monitoring on medium rise reinforced concrete building using ambient vibration method

    Science.gov (United States)

    Kamarudin, A. F.; Mokhatar, S. N.; Zainal Abidin, M. H.; Daud, M. E.; Rosli, M. S.; Ibrahim, A.; Ibrahim, Z.; Noh, M. S. Md

    2018-04-01

    Monitoring of structural health from initial stage of building construction to its serviceability is an ideal practise to assess for any structural defects or damages. Structural integrity could be intruded by natural destruction or structural deterioration, and worse if without remedy action on monitoring, building re-assessment or maintenance is taken. In this study the application of ambient vibration (AV) testing is utilized to evaluate the health of eighth stories medium rise reinforced concrete building in Universiti Tun Hussein Onn Malaysia (UTHM), based comparison made between the predominant frequency, fo, determined in year 2012 and 2017. For determination of fo, popular method of Fourier Amplitude Spectra (FAS) was used to transform the ambient vibration time series by using 1 Hz tri-axial seismometer sensors and City SharkII data recorder. From the results, it shows the first mode frequencies from FAS curves indicate at 2.04 Hz in 2012 and 1.97 Hz in 2017 with only 3.14% of frequency reduction. However, steady state frequencies shown at the second and third modes frequencies of 2.42 Hz and 3.31 Hz by both years. Two translation mode shapes were found at the first and second mode frequencies in the North-South (NS-parallel to building transverse axis) and East-West (EsW-parallel to building longitudinal axis) components, and the torsional mode shape shows as the third mode frequency in both years. No excessive deformation amplitude was found at any selective floors based on comparison made between three mode shapes produced, that could bring to potential feature of structural deterioration. Low percentages of natural frequency disparity within five years of duration interval shown by the first mode frequencies under ambient vibration technique was considered in good health state, according to previous researchers recommendation at acceptable percentages below 5 to 10% over the years.

  18. Multivariate determinants of self-management in Health Care: assessing Health Empowerment Model by comparison between structural equation and graphical models approaches

    Directory of Open Access Journals (Sweden)

    Filippo Trentini

    2015-03-01

    Full Text Available Backgroung. In public health one debated issue is related to consequences of improper self-management in health care.  Some theoretical models have been proposed in Health Communication theory which highlight how components such general literacy and specific knowledge of the disease might be very important for effective actions in healthcare system.  Methods. This  paper aims at investigating the consistency of Health Empowerment Model by means of both graphical models approach, which is a “data driven” method and a Structural Equation Modeling (SEM approach, which is instead “theory driven”, showing the different information pattern that can be revealed in a health care research context.The analyzed dataset provides data on the relationship between the Health Empowerment Model constructs and the behavioral and health status in 263 chronic low back pain (cLBP patients. We used the graphical models approach to evaluate the dependence structure in a “blind” way, thus learning the structure from the data.Results. From the estimation results dependence structure confirms links design assumed in SEM approach directly from researchers, thus validating the hypotheses which generated the Health Empowerment Model constructs.Conclusions. This models comparison helps in avoiding confirmation bias. In Structural Equation Modeling, we used SPSS AMOS 21 software. Graphical modeling algorithms were implemented in a R software environment.

  19. Multi-site damage localization in anisotropic plate-like structures using an active guided wave structural health monitoring system

    International Nuclear Information System (INIS)

    Moll, J; Schulte, R T; Fritzen, C-P; Hartmann, B; Nelles, O

    2010-01-01

    A new approach for structural health monitoring using guided waves in plate-like structures has been developed. In contrast to previous approaches, which mainly focused on isotropic or quasi-isotropic plates, the proposed algorithm does not assume any simplifications regarding anisotropic wave propagation. Thus, it can be used to improve the probability of detection. In this paper the mathematical background for damage localization in anisotropic plates will be introduced. This is an extension of the widely known ellipse method. The formalism is based on a distributed sensor network, where each piezoelectric sensor acts in turn as an actuator. The automatic extraction of the onset time of the first waveform in the differential signal in combination with a statistical post-processing via a two-dimensional probability density function and the application of the expectation-maximization algorithm allows a completely automatic localization procedure. Thus, multiple damages can be identified at the same time. The present study uses ultrasonic signals provided by the spectral element method. This simulation approach shows good agreement with experimental measurements. A local linear neural network is used to model the nonlinear dispersion curves. The benefit of using a neural network approach is to increase the angular resolution that results from the sparse sensor network. Furthermore, it can be used to shorten the computational time for the damage localization procedure

  20. Electromechanical impedance-based health diagnosis for tendon and anchorage zone in a nuclear containment structure

    Science.gov (United States)

    Min, Jiyoung; Shim, Hyojin; Yun, Chung-Bang

    2012-04-01

    For a nuclear containment structure, the structural health monitoring is essential because of its high potential risk and grave social impact. In particular, the tendon and anchorage zone are to be monitored because they are under high tensile or compressive stress. In this paper, a method to monitor the tendon force and the condition of the anchorage zone is presented by using the impedance-based health diagnosis system. First, numerical simulations were conducted for cases with various loose tensile forces on the tendon as well as damages on the bearing plate and concrete structure. Then, experimental studies were carried out on a scaled model of the anchorage system. The relationship between the loose tensile force and the impedance-based damage index was analyzed by a regression analysis. When a structure gets damaged, the damage index increases so that the status of damage can be identified. The results of the numerical and experimental studies indicate a big potential of the proposed impedance-based method for monitoring the tendon and anchorage system.

  1. Integration of computer imaging and sensor data for structural health monitoring of bridges

    International Nuclear Information System (INIS)

    Zaurin, R; Catbas, F N

    2010-01-01

    The condition of civil infrastructure systems (CIS) changes over their life cycle for different reasons such as damage, overloading, severe environmental inputs, and ageing due normal continued use. The structural performance often decreases as a result of the change in condition. Objective condition assessment and performance evaluation are challenging activities since they require some type of monitoring to track the response over a period of time. In this paper, integrated use of video images and sensor data in the context of structural health monitoring is demonstrated as promising technologies for the safety of civil structures in general and bridges in particular. First, the challenges and possible solutions to using video images and computer vision techniques for structural health monitoring are presented. Then, the synchronized image and sensing data are analyzed to obtain unit influence line (UIL) as an index for monitoring bridge behavior under identified loading conditions. Subsequently, the UCF 4-span bridge model is used to demonstrate the integration and implementation of imaging devices and traditional sensing technology with UIL for evaluating and tracking the bridge behavior. It is shown that video images and computer vision techniques can be used to detect, classify and track different vehicles with synchronized sensor measurements to establish an input–output relationship to determine the normalized response of the bridge

  2. Integrated system of structural health monitoring and intelligent management for a cable-stayed bridge.

    Science.gov (United States)

    Chen, Bin; Wang, Xu; Sun, Dezhang; Xie, Xu

    2014-01-01

    It is essential to construct structural health monitoring systems for large important bridges. Zhijiang Bridge is a cable-stayed bridge that was built recently over the Hangzhou Qiantang River (the largest river in Zhejiang Province). The length of Zhijiang Bridge is 478 m, which comprises an arched twin-tower space and a twin-cable plane structure. As an example, the present study describes the integrated system of structural health monitoring and intelligent management for Zhijiang Bridge, which comprises an information acquisition system, data management system, evaluation and decision-making system, and application service system. The monitoring components include the working environment of the bridge and various factors that affect bridge safety, such as the stress and strain of the main bridge structure, vibration, cable force, temperature, and wind speed. In addition, the integrated system includes a forecasting and decision-making module for real-time online evaluation, which provides warnings and makes decisions based on the monitoring information. From this, the monitoring information, evaluation results, maintenance decisions, and warning information can be input simultaneously into the bridge monitoring center and traffic emergency center to share the monitoring data, thereby facilitating evaluations and decision making using the system.

  3. A new type of intelligent wireless sensing network for health monitoring of large-size structures

    Science.gov (United States)

    Lei, Ying; Liu, Ch.; Wu, D. T.; Tang, Y. L.; Wang, J. X.; Wu, L. J.; Jiang, X. D.

    2009-07-01

    In recent years, some innovative wireless sensing systems have been proposed. However, more exploration and research on wireless sensing systems are required before wireless systems can substitute for the traditional wire-based systems. In this paper, a new type of intelligent wireless sensing network is proposed for the heath monitoring of large-size structures. Hardware design of the new wireless sensing units is first studied. The wireless sensing unit mainly consists of functional modules of: sensing interface, signal conditioning, signal digitization, computational core, wireless communication and battery management. Then, software architecture of the unit is introduced. The sensing network has a two-level cluster-tree architecture with Zigbee communication protocol. Important issues such as power saving and fault tolerance are considered in the designs of the new wireless sensing units and sensing network. Each cluster head in the network is characterized by its computational capabilities that can be used to implement the computational methodologies of structural health monitoring; making the wireless sensing units and sensing network have "intelligent" characteristics. Primary tests on the measurement data collected by the wireless system are performed. The distributed computational capacity of the intelligent sensing network is also demonstrated. It is shown that the new type of intelligent wireless sensing network provides an efficient tool for structural health monitoring of large-size structures.

  4. Integrated System of Structural Health Monitoring and Intelligent Management for a Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Bin Chen

    2014-01-01

    Full Text Available It is essential to construct structural health monitoring systems for large important bridges. Zhijiang Bridge is a cable-stayed bridge that was built recently over the Hangzhou Qiantang River (the largest river in Zhejiang Province. The length of Zhijiang Bridge is 478 m, which comprises an arched twin-tower space and a twin-cable plane structure. As an example, the present study describes the integrated system of structural health monitoring and intelligent management for Zhijiang Bridge, which comprises an information acquisition system, data management system, evaluation and decision-making system, and application service system. The monitoring components include the working environment of the bridge and various factors that affect bridge safety, such as the stress and strain of the main bridge structure, vibration, cable force, temperature, and wind speed. In addition, the integrated system includes a forecasting and decision-making module for real-time online evaluation, which provides warnings and makes decisions based on the monitoring information. From this, the monitoring information, evaluation results, maintenance decisions, and warning information can be input simultaneously into the bridge monitoring center and traffic emergency center to share the monitoring data, thereby facilitating evaluations and decision making using the system.

  5. Structuring and coding in health care records: a qualitative analysis using diabetes as a case study

    Directory of Open Access Journals (Sweden)

    Ann R R Robertson

    2015-03-01

    Full Text Available Background   Globally, diabetes mellitus presents a substantial burden to individuals and healthcare systems. Structuring and/or coding of medical records underpin attempts to improve information sharing and searching, potentially bringing clinical and secondary uses benefits.Aims and objectives   We investigated if, how and why records for adults with diabetes were structured and/or coded, and explored stakeholders’ perceptions of current practice.Methods   We carried out a qualitative, theoretically-informed case study of documenting healthcare information for diabetes patients in family practice and hospital settings, using semi-structured interviews, observations, systems demonstrations and documentary data.Results   We conducted 22 interviews and four on-site observations, and reviewed 25 documents. For secondary uses – research, audit, public health and service planning – the benefits of highly structured and coded diabetes data were clearly articulated. Reported clinical benefits in terms of managing and monitoring diabetes, and perhaps encouraging patient self-management, were modest. We observed marked differences in levels of record structuring and/or coding between settings, and found little evidence that these data were being exploited to improve information sharing between them.Conclusions   Using high levels of data structuring and coding in medical records for diabetes patients has potential to be exploited more fully, and lessons might be learned from successful developments elsewhere in the UK.

  6. Integration of High-Resolution Laser Displacement Sensors and 3D Printing for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Shu-Wei Chang

    2017-12-01

    Full Text Available This paper presents a novel experimental design for complex structural health monitoring (SHM studies achieved by integrating 3D printing technologies, high-resolution laser displacement sensors, and multiscale entropy SHM theory. A seven-story structure with a variety of composite bracing systems was constructed using a dual-material 3D printer. A wireless Bluetooth vibration speaker was used to excite the ground floor of the structure, and high-resolution laser displacement sensors (1-μm resolution were used to monitor the displacement history on different floors. Our results showed that the multiscale entropy SHM method could detect damage on the 3D-printed structures. The results of this study demonstrate that integrating 3D printing technologies and high-resolution laser displacement sensors enables the design of cheap, fast processing, complex, small-scale civil structures for future SHM studies. The novel experimental design proposed in this study provides a suitable platform for investigating the validity and sensitivity of SHM in different composite structures and damage conditions for real life applications in the future.

  7. Integration of High-Resolution Laser Displacement Sensors and 3D Printing for Structural Health Monitoring.

    Science.gov (United States)

    Chang, Shu-Wei; Lin, Tzu-Kang; Kuo, Shih-Yu; Huang, Ting-Hsuan

    2017-12-22

    This paper presents a novel experimental design for complex structural health monitoring (SHM) studies achieved by integrating 3D printing technologies, high-resolution laser displacement sensors, and multiscale entropy SHM theory. A seven-story structure with a variety of composite bracing systems was constructed using a dual-material 3D printer. A wireless Bluetooth vibration speaker was used to excite the ground floor of the structure, and high-resolution laser displacement sensors (1-μm resolution) were used to monitor the displacement history on different floors. Our results showed that the multiscale entropy SHM method could detect damage on the 3D-printed structures. The results of this study demonstrate that integrating 3D printing technologies and high-resolution laser displacement sensors enables the design of cheap, fast processing, complex, small-scale civil structures for future SHM studies. The novel experimental design proposed in this study provides a suitable platform for investigating the validity and sensitivity of SHM in different composite structures and damage conditions for real life applications in the future.

  8. Development and validation of a strain-based Structural Health Monitoring system

    Science.gov (United States)

    Katsikeros, Ch. E.; Labeas, G. N.

    2009-02-01

    An innovative Structural Health Monitoring (SHM) methodology, based on structural strain measurements, which are processed by a back-propagation feed-forward Artificial Neural Network (ANN), is proposed. The demonstration of the SHM methodology and the identification of its capabilities and drawbacks are performed by applying the method in the prediction of fatigue damage states of a typical aircraft cracked lap-joint structure. An ANN of suitable architecture is developed and trained by numerically generated strain data sets, which have been preprocessed by Fast Fourier Transformation (FFT) for the extraction of the Fourier Descriptors (FDs). The Finite Element (FE) substructuring technique is implemented in the stress and strain analysis of the lap-joint structure, due to its efficiency in the calculation of the numerous strain data, which are necessary for the ANN training. The trained network is successfully validated, as it is proven capable to accurately predict crack positions and lengths of a lap-joint structure, which is damaged by fatigue cracks of unknown location and extent. The proposed methodology is applicable to the identification of more complex types of damage or to other critical structural locations, as its basic concept is generic.

  9. Structural Health Monitoring of a Composite Panel Based on PZT Sensors and a Transfer Impedance Framework.

    Science.gov (United States)

    Dziendzikowski, Michal; Niedbala, Patryk; Kurnyta, Artur; Kowalczyk, Kamil; Dragan, Krzysztof

    2018-05-11

    One of the ideas for development of Structural Health Monitoring (SHM) systems is based on excitation of elastic waves by a network of PZT piezoelectric transducers integrated with the structure. In the paper, a variant of the so-called Transfer Impedance (TI) approach to SHM is followed. Signal characteristics, called the Damage Indices (DIs), were proposed for data presentation and analysis. The idea underlying the definition of DIs was to maintain most of the information carried by the voltage induced on PZT sensors by elastic waves. In particular, the DIs proposed in the paper should be sensitive to all types of damage which can influence the amplitude or the phase of the voltage induced on the sensor. Properties of the proposed DIs were investigated experimentally using a GFRP composite panel equipped with PZT networks attached to its surface and embedded into its internal structure. Repeatability and stability of DI indications under controlled conditions were verified in tests. Also, some performance indicators for surface-attached and structure-embedded sensors were obtained. The DIs' behavior was dependent mostly on the presence of a simulated damage in the structure. Anisotropy of mechanical properties of the specimen, geometrical properties of PZT network as well as, to some extent, the technology of sensor integration with the structure were irrelevant for damage indication. This property enables the method to be used for damage detection and classification.

  10. Staff survey of organizational structure and process for a Public Health Department.

    Science.gov (United States)

    Dwyer, J J

    1995-01-01

    A survey of 227 North York Public Health Department (NYPHD) staff provided their perspective on the organizational structure. They perceived that (a) the departmental and divisional organizational structures are effective for program delivery, (b) the Central Resources structure and divisional and departmental reporting structures are moderately effective for program delivery, (c) the decentralized office structure is an advantage for service delivery but less so for administration and intra-division and inter-division communication, (d) the mandatory program structure involves low to moderate interdisciplinary teamwork and moderately impacts service delivery, (e) intra-division and management-staff communication are fair but inter-division and office communication are between poor and fair, (f) education, research, and service are moderately integrated, and (g) the divisional and departmental work atmospheres are a little positive. Management perceived greater participation in program planning, more frequent communication with other divisions, a number of education and research opportunities from various divisions/units, and more management recognition than front line staff did.

  11. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    Science.gov (United States)

    Ye, X. W.; Su, Y. H.; Han, J. P.

    2014-01-01

    In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM) of civil infrastructure. PMID:25133250

  12. Structural health monitoring of civil infrastructure using optical fiber sensing technology: a comprehensive review.

    Science.gov (United States)

    Ye, X W; Su, Y H; Han, J P

    2014-01-01

    In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM) of civil infrastructure.

  13. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    X. W. Ye

    2014-01-01

    Full Text Available In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM of civil infrastructure.

  14. A case study examination of structure and function in a state health department chronic disease unit.

    Science.gov (United States)

    Alongi, Jeanne

    2015-04-01

    I explored the structural and operational practices of the chronic disease prevention and control unit of a state health department and proposed a conceptual model of structure, function, and effectiveness for future study. My exploratory case study examined 7 elements of organizational structure and practice. My interviews with staff and external stakeholders of a single chronic disease unit yielded quantitative and qualitative data that I coded by perspective, process, relationship, and activity. I analyzed these for patterns and emerging themes. Chi-square analysis revealed significant correlations among collaboration with goal ambiguity, political support, and responsiveness, and evidence-based decisions with goal ambiguity and responsiveness. Although my study design did not permit conclusions about causality, my findings suggested that some elements of the model might facilitate effectiveness for chronic disease units and should be studied further. My findings might have important implications for identifying levers around which capacity can be built that may strengthen effectiveness.

  15. Design, Manufacturing and Experimental Validation of Optical Fiber Sensors Based Devices for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Angela CORICCIATI

    2016-06-01

    Full Text Available The use of optical fiber sensors is a promising and rising technique used for Structural Health Monitoring (SHM, because permit to monitor continuously the strain and the temperature of the structure where they are applied. In the present paper three different types of smart devices, that are composite materials with an optical fiber sensor embedded inside them during the manufacturing process, are described: Smart Patch, Smart Rebar and Smart Textile, which are respectively a plate for local exterior intervention, a rod for shear and flexural interior reinforcement and a textile for an external whole application. In addition to the monitoring aim, the possible additional function of these devices could be the reinforcement of the structures where they are applied. In the present work, after technology manufacturing description, the experimental laboratory characterization of each device is discussed. At last, smart devices application on medium scale masonry walls and their validation by mechanical tests is described.

  16. A Methodological Review of Piezoelectric Based Acoustic Wave Generation and Detection Techniques for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Zhigang Sun

    2013-01-01

    Full Text Available Piezoelectric transducers have a long history of applications in nondestructive evaluation of material and structure integrity owing to their ability of transforming mechanical energy to electrical energy and vice versa. As condition based maintenance has emerged as a valuable approach to enhancing continued aircraft airworthiness while reducing the life cycle cost, its enabling structural health monitoring (SHM technologies capable of providing on-demand diagnosis of the structure without interrupting the aircraft operation are attracting increasing R&D efforts. Piezoelectric transducers play an essential role in these endeavors. This paper is set forth to review a variety of ingenious ways in which piezoelectric transducers are used in today’s SHM technologies as a means of generation and/or detection of diagnostic acoustic waves.

  17. On the Value of Structural Health Monitoring Information for the Operation of Wind Parks

    DEFF Research Database (Denmark)

    Thöns, Sebastian; Faber, Michael H.; Val, Dimitri V.

    2017-01-01

    wind turbine systems and its components is developed accounting for the wind park functionality, i.e. power production, its operation and its cascading damage and failure scenarios. This system model facilitates to quantify the expected benefits and risks throughout the service life accounting......In the present paper, an approach for the quantification of the Value of Structural Health Monitoring (SHM) Information building upon a framework for infrastructure system utility and decision analysis is developed and applied to the operation of wind parks. The quantification of the value of SHM...... facilitates a benefit and risk informed assessment and optimization of SHM strategies and encompasses models for the infrastructure functionality, the structural constituent and system risks and its management as well as the performance of SHM strategies. A wind park system model incorporating the structural...

  18. Design of a piezoelectric-based structural health monitoring system for damage detection in composite materials

    Science.gov (United States)

    Kessler, Seth S.; Spearing, S. Mark

    2002-07-01

    Cost-effective and reliable damage detection is critical for the utilization of composite materials. This paper presents the conclusions of an experimental and analytical survey of candidate methods for in-situ damage detection in composite structures. Experimental results are presented for the application of modal analysis and Lamb wave techniques to quasi-isotropic graphite/epoxy test specimens containing representative damage. Piezoelectric patches were used as actuators and sensors for both sets of experiments. Modal analysis methods were reliable for detecting small amounts of global damage in a simple composite structure. By comparison, Lamb wave methods were sensitive to all types of local damage present between the sensor and actuator, provided useful information about damage presence and severity, and present the possibility of estimating damage type and location. Analogous experiments were also performed for more complex built-up structures. These techniques are suitable for structural health monitoring applications since they can be applied with low power conformable sensors and can provide useful information about the state of a structure during operation. Piezoelectric patches could also be used as multipurpose sensors to detect damage by a variety of methods such as modal analysis, Lamb wave, acoustic emission and strain based methods simultaneously, by altering driving frequencies and sampling rates. This paper present guidelines and recommendations drawn from this research to assist in the design of a structural health monitoring system for a vehicle. These systems will be an important component in future designs of air and spacecraft to increase the feasibility of their missions.

  19. Understanding the structure of community collaboration: the case of one Canadian health promotion network.

    Science.gov (United States)

    Barnes, Martha; Maclean, Joanne; Cousens, Laura

    2010-06-01

    In 2004, over 6.8 million Canadians were considered overweight, with an additional 2.4 million labeled clinically obese. Due to these escalating levels of obesity in Canada, physical activity is being championed by politicians, physicians, educators and community members as a means to address this health crisis. In doing so, many organizations are being called upon to provide essential physical activity services and programs to combat rising obesity rates. Yet, strategies for achieving these organizations' mandates, which invariably involve stretching already scarce resources, are difficult to implement and sustain. One strategy for improving the health and physical activity levels of people in communities has been the creation of inter-organizational networks of service providers. Yet, little is known about whether networks are effective in addressing policy issues in non-clinical health settings. The purpose of this investigation was 2-fold; to use whole network analysis to determine the structure of one health promotion network in Canada, and to identify the types of ties shared by actors in the health network. Findings revealed a network wherein information sharing constituted the basis for collaboration, whereas efforts related to sharing resources, marketing and/or fundraising endeavors were less evident.

  20. Family Structure and Child Health: Does the Sex Composition of Parents Matter?

    Science.gov (United States)

    Reczek, Corinne; Spiker, Russell; Liu, Hui; Crosnoe, Robert

    2016-10-01

    The children of different-sex married couples appear to be advantaged on a range of outcomes relative to the children of different-sex cohabiting couples. Despite the legalization of same-sex marriage in the United States, whether and how this general pattern extends to the children of same-sex married and cohabiting couples is unknown. This study examines this question with nationally representative data from the 2004-2013 pooled National Health Interview Survey (NHIS). Results reveal that children in cohabiting households have poorer health outcomes than children in married households regardless of the sex composition of their parents. Children in same-sex and different-sex married households are relatively similar to each other on health outcomes, as are children in same-sex and different-sex cohabiting households. These patterns are not fully explained by socioeconomic differences among the four different types of families. This evidence can inform general debates about family structure and child health as well as policy interventions aiming to reduce child health disparities.

  1. A model for oral health gradients in children: using structural equation modeling.

    Science.gov (United States)

    Behbahanirad, A; Joulaei, H; Jamali, J; Vossoughi, M; Golkari, A

    2017-03-01

    Detecting the underlying socioeconomic and behavioral determinants is essential for reducing oral health disparities in children. To test a conceptual model in children to explore the interaction amongst social, environmental, behavioral factors and oral health outcomes. This analytic cross-sectional study was performed in 2014-2015 in Shiraz, Iran. The sampling was conducted using a multistage stratified design to represent the whole 6-year-olds in Shiraz County. Participants were 830, 6-year-old first grade primary schoolchildren and their parents. Children were examined to register decayed, missing and filled teeth (dmft) and simplified oral hygiene index (OHI-S). Parents were asked for data on socio-cultural risk factors, oral health behaviors and children's oral health related quality of life (C-OHRQoL). Data on environmental risk factors were collected from several sources. The proposed model, a development of Peterson's, was tested using structural equation modeling (SEM). The tested model could empirically demonstrate the wide range of social and behavioral factors affecting C-OHRQoL. Socioeconomic status (SES) affected the OHRQoL of children through several pathways. Tooth brushing frequency, use of oral health services and consuming cariogenic foods were the mediators, through which SES affected dmft and subsequently C-OHRQoL. Using the modified Petersen's model and SEM, the paths in which different distal and proximal factors affect oral health outcomes in children could be clearly identified. It showed that addressing the underlying social, economic and behavioral determinants is essential for reducing oral health disparities among Iranian children. Copyright© 2017 Dennis Barber Ltd.

  2. Trends and structural shifts in health tourism: evidence from seasonal time-series data on health-related travel spending by Canada during 1970-2010.

    Science.gov (United States)

    Loh, Chung-Ping A

    2015-05-01

    There has been a growing interest in better understanding the trends and determinants of health tourism activities. While much of the expanding literature on health tourism offers theoretical or qualitative discussion, empirical evidences has been lacking. This study employs Canada's outbound health tourism activities as an example to examine the trends in health tourism and its association with changing domestic health care market characteristics. A time-series model that accounts for potential structural changes in the trend is employed to analyze the quarterly health-related travel spending series reported in the Balance of Payments Statistics (BOPS) during 1970-2010 (n = 156). We identified a structural shift point which marks the start of an accelerated growth of health tourism and a flattened seasonality in such activities. We found that the health tourism activities of Canadian consumers increase when the private investment in medical facilities declines or when the private MPI increases during the years following the structural-change. We discussed the possible linkage of the structural shift to the General Agreement on Trade in Services (GATS), which went into effect in January, 1995. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. An assessment of factorial structure and health-related quality of life in problem drug users using the Short Form 36 Health Survey

    NARCIS (Netherlands)

    Buchholz, Angela; Krol, Anneke; Rist, Fred; Nieuwkerk, Pythia T.; Schippers, Gerard M.

    2008-01-01

    AIMS: To confirm the factorial structure of the Short Form 36 Health Survey (SF-36) in problem drug users and to compare their health-related quality of life (HRQOL) with general Dutch population norms. METHOD: Data of 394 participants from the Amsterdam Cohort Study among drug users, who had

  4. The structure of mental health research: networks of influence among psychiatry and clinical psychology journals.

    Science.gov (United States)

    Haslam, N; Lusher, D

    2011-12-01

    Psychiatry and clinical psychology are the two dominant disciplines in mental health research, but the structure of scientific influence and information flow within and between them has never been mapped. Citations among 96 of the highest impact psychiatry and clinical psychology journals were examined, based on 10 052 articles published in 2008. Network analysis explored patterns of influence between journal clusters. Psychiatry journals tended to have greater influence than clinical psychology journals, and their influence was asymmetrical: clinical psychology journals cited psychiatry journals at a much higher rate than the reverse. Eight journal clusters were found, most dominated by a single discipline. Their citation network revealed an influential central cluster of 'core psychiatry' journals that had close affinities with a 'psychopharmacology' cluster. A group of 'core clinical psychology' journals was linked to a 'behavior therapy' cluster but both were subordinate to psychiatry journals. Clinical psychology journals were less integrated than psychiatry journals, and 'health psychology/behavioral medicine' and 'neuropsychology' clusters were relatively peripheral to the network. Scientific publication in the mental health field is largely organized along disciplinary lines, and is to some degree hierarchical, with clinical psychology journals tending to be structurally subordinate to psychiatry journals.

  5. Research potential of food and nutrition in the Family Health Strategy: A structured review

    Directory of Open Access Journals (Sweden)

    Ivana Aragão Lira Vasconcelos

    2014-01-01

    Full Text Available OBJECTIVE: Determine the profile of research groups and publications with food and nutrition-related actions promoted by the Family Health Strategy in Brazil since 1994. METHODS: Two procedures were used: structured review and research group search. The former searched the databases Web of Science, Medline, Lilacs, SciELO and Embase, and followed the principles that guide systematic reviews in the Cochrane Collaboration. The references of the selected articles were also consulted. The research groups were searched in the Research Group Directory of the National Council for Scientific and Technological Development. RESULTS: A total of 54 articles published between 2002 and 2012 in 20 different journals were identified. Ten of these were retrieved from the references section of other articles. Focusing mostly on children from the Southeast region, these studies were coordinated by dieticians, nurses, and physicians. Diabetes Mellitus, high blood pressure, and breastfeeding were the most common topics (n=23. The quantitative methodology was employed by 42 articles, most about diagnoses. Only five research groups studied the Family Health Strategy, despite the growing number of studies in the area over the years. CONCLUSION: Despite the growing scientific production, the findings of this structured review indicate that few studies focused on food and nutrition in the Family Health Strategy, probably because of the existence of few research groups in the country. More comprehensive and consistent studies on the topic are needed.

  6. The evolving organizational structure of academic health centers: the case of the University of Florida.

    Science.gov (United States)

    Barrett, Douglas J

    2008-09-01

    The organizational structures of academic health centers (AHCs) vary widely, but they all exist along a continuum of integration--that is, the degree to which the academic and clinical missions operate under a single administrative and governance structure. This author provides a brief overview of the topic of AHC integration, including the pros and cons of more integrated or less integrated models. He then traces the evolution of the University of Florida (UF) Health Science Center, which was created in the 1950s as a fully integrated AHC and which now operates under a more distributed management and governance model. Starting as a completely integrated AHC, UF's Health Science Center reached a time of maximal nonintegration (or dys-integration) in the late 1990s and at the beginning of this decade. Circumstances are now pushing the expanding clinical and academic enterprises to be more together as they face the challenges of market competition, federal research budget constraints, and reengineering clinical operations to reduce costs, enhance access, and improve quality and patient safety. Although formal organizational integration may not be possible or appropriate for any number of legal or political reasons, the author suggests that AHCs should strive for "functional integration" to be successful in the current turbulent environment.

  7. Development of structural health monitoring and early warning system for reinforced concrete system

    International Nuclear Information System (INIS)

    Iranata, Data; Wahyuni, Endah; Murtiadi, Suryawan; Widodo, Amien; Riksakomara, Edwin; Sani, Nisfu Asrul

    2015-01-01

    Many buildings have been damaged due to earthquakes that occurred recently in Indonesia. The main cause of the damage is the large deformation of the building structural component cannot accommodate properly. Therefore, it is necessary to develop the Structural Health Monitoring System (SHMS) to measure precisely the deformation of the building structural component in the real time conditions. This paper presents the development of SHMS for reinforced concrete structural system. This monitoring system is based on deformation component such as strain of reinforcement bar, concrete strain, and displacement of reinforced concrete component. Since the deformation component has exceeded the limit value, the warning message can be sent to the building occupies. This warning message has also can be performed as early warning system of the reinforced concrete structural system. The warning message can also be sent via Short Message Service (SMS) through the Global System for Mobile Communications (GSM) network. Hence, the SHMS should be integrated with internet modem to connect with GSM network. Additionally, the SHMS program is verified with experimental study of simply supported reinforced concrete beam. Verification results show that the SHMS has good agreement with experimental results

  8. Steel bridges structural health monitoring based on operational modal analysis accommodating evaluation of uncertainty

    Directory of Open Access Journals (Sweden)

    Saeid Jahan

    2017-11-01

    Full Text Available Structural damage detection is based on that the dynamic response of structure will change because of damage. Hence, it is possible to estimate the location and severity of damage leads to changes in the dynamic response before and after the damage. In this study, the genetic fuzzy system has been used for bridge structural health monitoring. A key objective of using genetic algorithms is to automate the design of fuzzy systems. This method is used for damage detection of a single span railway bridge with steel girders and a concrete bridge. For studying damage detection, the numerical models of these two bridges are built with the measured dynamic characteristics. A three-dimensional finite element model and a single two-dimensional girders model of the bridge have been constructed to study usefulness of the genetic fuzzy system for damage detection and the effectiveness of modeling. After analysis to control the uncertainties, the measured frequencies are contaminated with some noise and the effect of that on the achievement of damage detection method is evaluated. The present study has shown that the natural frequency has appropriate sensitivity to different damage scenarios in the structure. In addition, the natural frequency in comparison with other modal parameters, is less affected by random noise. Increasing the number of measurement modes and using torsional modes, will lead to an accurate damage diagnosis even in symmetrical structures.

  9. Pairwise graphical models for structural health monitoring with dense sensor arrays

    Science.gov (United States)

    Mohammadi Ghazi, Reza; Chen, Justin G.; Büyüköztürk, Oral

    2017-09-01

    Through advances in sensor technology and development of camera-based measurement techniques, it has become affordable to obtain high spatial resolution data from structures. Although measured datasets become more informative by increasing the number of sensors, the spatial dependencies between sensor data are increased at the same time. Therefore, appropriate data analysis techniques are needed to handle the inference problem in presence of these dependencies. In this paper, we propose a novel approach that uses graphical models (GM) for considering the spatial dependencies between sensor measurements in dense sensor networks or arrays to improve damage localization accuracy in structural health monitoring (SHM) application. Because there are always unobserved damaged states in this application, the available information is insufficient for learning the GMs. To overcome this challenge, we propose an approximated model that uses the mutual information between sensor measurements to learn the GMs. The study is backed by experimental validation of the method on two test structures. The first is a three-story two-bay steel model structure that is instrumented by MEMS accelerometers. The second experimental setup consists of a plate structure and a video camera to measure the displacement field of the plate. Our results show that considering the spatial dependencies by the proposed algorithm can significantly improve damage localization accuracy.

  10. Dimensional structure of the oral health-related quality of life in healthy Spanish workers

    Directory of Open Access Journals (Sweden)

    López Joaquín F

    2010-02-01

    Full Text Available Abstract Background Oral health-related quality of life (OHQoL is conceived as a multidimensional construct. Here our aim was to investigate the dimensional structure of OHQoL as measured by the Spanish versions of the Oral Impacts on Daily Performance (OIDP and the Oral Health Impact Profile (OHIP-14 questionnaires applied simultaneously. Methods We recruited a consecutive sample of 270 healthy Spanish workers visiting the Employment Risk Prevention Centre for a routine medical check-up. OHIP-14 was self-completed by participants but the OIDP was completed in face-to-face interviews. An Exploratory Factor Analysis (EFA was performed to identify the underlying dimensions of the OHQoL construct assessed by both instruments. This factorial structure was later confirmed by Confirmatory Factor Analysis (CFA using several estimators of goodness of fit indices. Results EFA and the CFA identified and respectively confirmed a set of 3 underlying factors in both questionnaires that could be interpreted as functional limitation, pain-discomfort, and psychosocial impacts. The model achieved was seen to fit properly for both instruments, but the factorial structure was clearer for the OIDP. Conclusions The results provide evidence for construct equivalence in the latent factors assessed by both OIDP and OHIP-14, suggesting that OHQoL is a three-dimensional construct. The prevalence of impact on these three factors was coherent between both indicators, pain-discomfort having the highest prevalence, followed by psycho-social impact, and functional limitation.

  11. Review on energy harvesting for structural health monitoring in aeronautical applications

    Science.gov (United States)

    Le, Minh Quyen; Capsal, Jean-Fabien; Lallart, Mickaël; Hebrard, Yoann; Van Der Ham, Andre; Reffe, Nicolas; Geynet, Lionel; Cottinet, Pierre-Jean

    2015-11-01

    This paper reviews recent developments in energy harvesting technologies for structural health monitoring (SHM) in aeronautical applications. Aeronautical industries show a great deal of interest in obtaining technologies that can be used to monitor the health of machinery and structures. In particular, the need for self-sufficient monitoring of structures has been ever-increasing in recent years. Autonomous SHM systems typically include embedded sensors, and elements for data acquisition, wireless communication, and energy harvesting. Among all of these components, this paper focuses on energy harvesting technologies. Actually, low-power sensors and wireless communication components are used in newer SHM systems, and a number of researchers have recently investigated such techniques to extract energy from the local environment to power these stand-alone systems. The first part of the paper is dedicated to the different energy sources available in aeronautical applications, i.e., for airplanes and helicopters. The second part gives a presentation of the various devices developed for converting ambient energy into electric power. The last part is dedicated to a comparison of the different technologies and the future development of energy harvesting for aeronautical applications.

  12. Carbon fiber epoxy composites for both strengthening and health monitoring of structures.

    Science.gov (United States)

    Salvado, Rita; Lopes, Catarina; Szojda, Leszek; Araújo, Pedro; Gorski, Marcin; Velez, Fernando José; Castro-Gomes, João; Krzywon, Rafal

    2015-05-06

    This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the "wet process", which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.

  13. Carbon Fiber Epoxy Composites for Both Strengthening and Health Monitoring of Structures

    Directory of Open Access Journals (Sweden)

    Rita Salvado

    2015-05-01

    Full Text Available This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the “wet process”, which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.

  14. Do differences in the administrative structure of populations confound comparisons of geographic health inequalities?

    LENUS (Irish Health Repository)

    Jackson, Andrew L

    2010-08-18

    Abstract Background Geographical health inequalities are naturally described by the variation in health outcomes between areas (e.g. mortality rates). However, comparisons made between countries are hampered by our lack of understanding of the effect of the size of administrative units, and in particular the modifiable areal unit problem. Our objective was to assess how differences in geographic and administrative units used for disseminating data affect the description of health inequalities. Methods Retrospective study of standard populations and deaths aggregated by administrative regions within 20 European countries, 1990-1991. Estimated populations and deaths in males aged 0-64 were in 5 year age bands. Poisson multilevel modelling was conducted of deaths as standardised mortality ratios. The variation between regions within countries was tested for relationships with the mean region population size and the unequal distribution of populations within each country measured using Gini coefficients. Results There is evidence that countries whose regions vary more in population size show greater variation and hence greater apparent inequalities in mortality counts. The Gini coefficient, measuring inequalities in population size, ranged from 0.1 to 0.5 between countries; an increase of 0.1 was accompanied by a 12-14% increase in the standard deviation of the mortality rates between regions within a country. Conclusions Apparently differing health inequalities between two countries may be due to differences in geographical structure per se, rather than having any underlying epidemiological cause. Inequalities may be inherently greater in countries whose regions are more unequally populated.

  15. Neglected environmental health impacts of China's supply-side structural reform.

    Science.gov (United States)

    Zhang, Wei; Zhang, Lei; Li, Ying; Tian, Yuling; Li, Xiaoran; Zhang, Xue; Mol, Arthur P J; Sonnenfeld, David A; Liu, Jianguo; Ping, Zeyu; Chen, Long

    2018-03-15

    "Supply-side structural reform" (SSSR) has been the most important ongoing economic reform in China since 2015, but its important environmental health effects have not been properly assessed. The present study addresses that gap by focusing on reduction of overcapacity in the coal, steel, and iron sectors, combined with reduction of emissions of sulfur dioxide (SO 2 ), nitrogen oxide (NO x ), and fine particulate matter (PM 2.5 ), and projecting resultant effects on air quality and public health across cities and regions in China. Modeling results indicate that effects on air quality and public health are visible and distributed unevenly across the country. This assessment provides quantitative evidence supporting projections of the transregional distribution of such effects. Such uneven transregional distribution complicates management of air quality and health risks in China. The results challenge approaches that rely solely on cities to improve air quality. The article concludes with suggestions on how to integrate SSSR measures with cities' air quality improvement attainment planning and management performance evaluation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Experimental Research on Quick Structural Health Monitoring Technique for Bridges Using Smartphone

    Directory of Open Access Journals (Sweden)

    Xuefeng Zhao

    2016-01-01

    Full Text Available In the recent years, with the development and popularization of smartphone, the utilization of smartphone in the Structural Health Monitoring (SHM has attracted increasing attention owing to its unique feature. Since bridges are of great importance to society and economy, bridge health monitoring has very practical significance during its service life. Furthermore, rapid damage assessment of bridge after an extreme event such as earthquake is very important in the recovery work. Smartphone-based bridge health monitoring and postevent damage evaluation have advantages over the conventional monitoring techniques, such as low cost, ease of installation, and convenience. Therefore, this study investigates the implementation feasibility of the quick bridge health monitoring technique using smartphone. A novel vision-based cable force measurement method using smartphone camera is proposed, and, then, its feasibility and practicality is initially validated through cable model test. An experiment regarding multiple parameters monitoring of one bridge scale model is carried out. Parameters, such as acceleration, displacement, and angle, are monitored using smartphone. The experiment results show that there is a good agreement between the reference sensor and smartphone measurements in both time and frequency domains.

  17. Outcome Evidence for Structured Pediatric to Adult Health Care Transition Interventions: A Systematic Review.

    Science.gov (United States)

    Gabriel, Phabinly; McManus, Margaret; Rogers, Katherine; White, Patience

    2017-09-01

    To identify statistically significant positive outcomes in pediatric-to-adult transition studies using the triple aim framework of population health, consumer experience, and utilization and costs of care. Studies published between January 1995 and April 2016 were identified using the CINAHL, Ovid MEDLINE, PubMed, Scopus, and Web of Science databases. Included studies evaluated pre-evaluation and postevaluation data, intervention and comparison groups, and randomized clinic trials. The methodological strength of each study was assessed using the Effective Public Health Practice Project Quality Assessment Tool. Out of a total of 3844 articles, 43 met our inclusion criteria. Statistically significant positive outcomes were found in 28 studies, most often related to population health (20 studies), followed by consumer experience (8 studies), and service utilization (9 studies). Among studies with moderate to strong quality assessment ratings, the most common positive outcomes were adherence to care and utilization of ambulatory care in adult settings. Structured transition interventions often resulted in positive outcomes. Future evaluations should consider aligning with professional transition guidance; incorporating detailed intervention descriptions about transition planning, transfer, and integration into adult care; and measuring the triple aims of population health, experience, and costs of care. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Capturing structured, pulmonary disease-specific data elements in electronic health records.

    Science.gov (United States)

    Gronkiewicz, Cynthia; Diamond, Edward J; French, Kim D; Christodouleas, John; Gabriel, Peter E

    2015-04-01

    Electronic health records (EHRs) have the potential to improve health-care quality by allowing providers to make better decisions at the point of care based on electronically aggregated data and by facilitating clinical research. These goals are easier to achieve when key, disease-specific clinical information is documented as structured data elements (SDEs) that computers can understand and process, rather than as free-text/natural-language narrative. This article reviews the benefits of capturing disease-specific SDEs. It highlights several design and implementation considerations, including the impact on efficiency and expressivity of clinical documentation and the importance of adhering to data standards when available. Pulmonary disease-specific examples of collection instruments are provided from two commonly used commercial EHRs. Future developments that can leverage SDEs to improve clinical quality and research are discussed.

  19. [The semi-structured interview: at the border of public health and anthropology].

    Science.gov (United States)

    Imbert, Geneviève

    2010-09-01

    The interview is the tool for data collection the most used in the context of research conducted in health sciences, human sciences and social sciences. After completing some generalities about the different types of interviews, the focus is on semi-structured interview during its various stages including the processing and data analysis, this from the return of a lived experience of research in work on the border of the field of public health and that of anthropology. If this approach and contextualized the semistructured interview may a priori appear specific, the reader interested in the development of qualitative research in a humanistic perspective and the implementation of multidisciplinary strategies to ascertain its universal character.

  20. Structural Development of Health Resort Staff in the Republic of Crimea

    Directory of Open Access Journals (Sweden)

    Svetlana Yuryevna Tsekhla

    2015-09-01

    Full Text Available The subject matter of the research is the laws and mechanisms of development of employment in various sectors of the labor market of the Republic of Crimea. The article investigates the regional staffing structure in the development of economic activities of the Republic of Crimea, in particular, the health resort institution to identify priorities for the implementation of employment policies in the region. The main hypothesis of the study: a mismatch of basic parameters of transformation of the labor market in the Republic of Crimea and the educational system produces dysfunctionality of their interaction, causes conflict between the needs and requirements of the labor market and the training level, particularly in the health resort institution, as well as dysfunctionality of formal qualifications of graduates. The methodological basis of the research is a systematic approach to the study of the labor market in the Republic of Crimea and the utilization of statistical methods for analyzing the labor market. In the study, the dynamics of socio-economic development of the Crimean region was analyzed. The labor market conditions in the Crimean region were investigated, which revealed the main causes of imbalances in the labor market development. The analysis of the training of medical students in institutions of higher education was held. Groups of factors affecting the staffing structure in the region were determined. Analysis of the causes of the labor market imbalances in Crimea showed that the existing imbalance was caused by both objective and subjective reasons. Priority lines in employment policy in the health resort institution have been proposed. Their implementation will help to stabilize the situation with the medical staff, including the health resort institution; to improve human resources personnel, capable to provide a high level of service to recreants; to promote problem solving in the development of the Republic of Crimea in the

  1. Modal content based damage indicators and phased array transducers for structural health monitoring of aircraft structures using ultrasonic guided waves

    Science.gov (United States)

    Ren, Baiyang

    Composite materials, especially carbon fiber reinforced polymers (CFRP), have been widely used in the aircraft industry because of their high specific strength and stiffness, resistance to corrosion and good fatigue life. Due to their highly anisotropic material properties and laminated structures, joining methods like bolting and riveting are no longer appropriate for joining CFRP since they initiate defects during the assembly and severely compromise the integrity of the structure; thus new techniques for joining CFRP are highly demanded. Adhesive bonding is a promising method because it relieves stress concentration, reduces weight and provides smooth surfaces. Additionally, it is a low-cost alternative to the co-cured method which is currently used to manufacture components of aircraft fuselage. Adhesive defects, disbonds at the interface between adherend and adhesive layer, are focused on in this thesis because they can be initialized by either poor surface preparation during the manufacturing or fatigue loads during service. Aircraft need structural health monitoring (SHM) systems to increase safety and reduce loss, and adhesive bonds usually represent the hotspots of the assembled structure. There are many nondestructive evaluation (NDE) methods for bond inspection. However, these methods cannot be readily integrated into an SHM system because of the bulk size and weight of the equipment and requirement of accessibility to one side of the bonded joint. The first objective of this work is to develop instruments, actuators, sensors and a data acquisition system for SHM of bond lines using ultrasonic guided waves which are well known to be able to cover large volume of the structure and inaccessible regions. Different from widely used guided wave sensors like PZT disks, the new actuators, piezoelectric fiber composite (PFC) phased array transducers0 (PAT), can control the modal content of the excited waves and the new sensors, polyvinylidene fluoride (PVDF

  2. INCLINATION AND VIBRATION MEASUREMENT BY INERTIAL SENSING FOR STRUCTURAL HEALTH MONITORING

    Science.gov (United States)

    Sugisaki, Koichi; Abe, Masato; Koshimizu, Satoru

    To develop a practical health monitoring system, inertial sensing which can readily be done for wide variety of situations is useful. However inertial sensors are measuring inclination and acceleration in reference to gravity. Therefore inclination are influence by acceleration and vice versa caused measuring errors. Especially, errors are more affected at low-frequency band which is important to estimate displacement. In this study, to establish correcting theory for inertial sensing and to develop method to estimate parameters for some structural system. And conducted a field test targeted at the real railway bridge to verify the effectiveness of the proposed method using response records of the pier under passing train load.

  3. Health and usage monitoring system for the small aircraft composite structure

    Science.gov (United States)

    Růžička, Milan; Dvořák, Milan; Schmidová, Nikola; Šašek, Ladislav; Štěpánek, Martin

    2017-07-01

    This paper is focused on the design of the health and usage monitoring system (HUMS) of the composite ultra-light aircrafts. A multichannel measuring system was developed and installed for recording of the long-term operational measurements of the UL airplane. Many fiber Bragg grating sensors were implemented into the composite aircraft structure, mainly in the glue joints. More than ten other analog functions and signals of the aircraft is monitored and can be correlated together. Changing of the FBG sensors responses in monitored places and their correlations, comparing with the calibration and recalibration procedures during a monitored life may indicate damage (eg. in bonded joints) and complements the HUMS system.

  4. Is it worth changing pattern recognition methods for structural health monitoring?

    Science.gov (United States)

    Bull, L. A.; Worden, K.; Cross, E. J.; Dervilis, N.

    2017-05-01

    The key element of this work is to demonstrate alternative strategies for using pattern recognition algorithms whilst investigating structural health monitoring. This paper looks to determine if it makes any difference in choosing from a range of established classification techniques: from decision trees and support vector machines, to Gaussian processes. Classification algorithms are tested on adjustable synthetic data to establish performance metrics, then all techniques are applied to real SHM data. To aid the selection of training data, an informative chain of artificial intelligence tools is used to explore an active learning interaction between meaningful clusters of data.

  5. Interplay between subsurface structural heterogeneity and multi-species reactive transport in human health risk predictions

    Science.gov (United States)

    Henri, C.; Fernandez-Garcia, D.; de Barros, F.

    2013-12-01

    The increasing presence of toxic chemicals released in the subsurface has led to a rapid growth of social concerns and to the need to develop and employ models that can predict the impact of groundwater contamination in human health under uncertainty. Monitored natural attenuation is a common remediation action in many contamination cases and represents an attractive decontamination method. However, natural attenuation can lead to the production of subspecies of distinct toxicity that may pose challenges in pollution management strategies. The actual threat that these contaminants pose to human health and ecosystems greatly depends on the interplay between the complexity of the geological system and the toxicity of the pollutants and their byproducts. In this work, we examine the interplay between multispecies reactive transport and the heterogeneous structure of the contaminated aquifer on human health risk predictions. The structure and organization of hydraulic properties of the aquifer can lead to preferential flow channels and fast contamination pathways. Early travel times, associated to channeling effects, are intuitively perceived as an indicator for high risk. However, in the case of multi-species systems, early travel times may also lead a limited production of daughter species that may contain higher toxicity as in the case of chlorinated compounds. In this work, we model a Perchloroethylene (PCE) contamination problem followed by the sequential first-order production/biodegradation of its daughter species Trichloroethylene (TCE), Dichloroethylene (DCE) and Vinyl Chlorine (VC). For this specific case, VC is known to be a highly toxic contaminant. By performing numerical experiments, we evaluate transport for two distinct three-dimensional aquifer structures. First, a multi-Gaussian hydraulic conductivity field and secondly, a geostatistically equivalent connected field. These two heterogeneity structures will provide two distinct ranges of mean travel

  6. Development of an Embedded Networked Sensing System for Structural Health Monitoring

    OpenAIRE

    Whang, Daniel; Xu, Ning; Rangwala, Sumit; Chintalapudi, Krishna; Govindan, Ramesh; Wallace, J W

    2004-01-01

    An innovative networked embedded sensing system for structural health monitoring is currently being developed. This sensor network has been prototyped in the laboratory, and will be deployed in a series of forced-vibration tests involving a full-scale, four-story office building in the next coming months. The low-power wireless seismic sensor system enables the acquisition of 15–30 channels of 16-bit accelerometer data at 128 Hz over a wireless network. The advantage of such a system is its t...

  7. Embedded Active Fiber Optic Sensing Network for Structural Health Monitoring in Harsh Environments

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Anbo [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

    2016-09-30

    This report summarizes technical progress on the program “Embedded Active Fiber Optic Sensing Network for Structural Health Monitoring in Harsh Environments” funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Center for Photonics Technology at Virginia Tech. The objective of this project is to develop a first-of-a-kind technology for remote fiber optic generation and detection of acoustic waves for structural health monitoring in harsh environments. During the project period, which is from April 1, 2013 to Septemeber 30, 2016, three different acoustic generation mechanisms were studied in detail for their applications in building a fiber optic acoustic generation unit (AGU), including laser induced plasma breakdown (LIP), Erbium-doped fiber laser absorption, and metal laser absorption. By comparing the performance of the AGUs designed based on these three mechanisms and analyzing the experimental results with simulations, the metal laser absorption method was selected to build a complete fiber optic structure health monitoring (FO-SHM) system for the proposed high temperature multi-parameter structure health monitoring application. Based on the simulation of elastic wave propagation and fiber Bragg grating acoustic pulse detection, an FO-SHM element together with a completed interrogation system were designed and built. This system was first tested on an aluminum piece in the low-temperature range and successfully demonstrated its capability of multi-parameter monitoring and multi-point sensing. In the later stages of the project, the research was focused on improving the surface attachment design and preparing the FO-SHM element for high temperature environment tests. After several upgrades to the surface attachment methods, the FO-SHM element was able to work reliably up to 600oC when attached to P91 pipes, which are the target material of this project. In the final stage of this project, this FO

  8. Optical fiber sensors FBG to the structural health monitoring of bridges

    International Nuclear Information System (INIS)

    Navarro-Henriquez, Francisco

    2014-01-01

    Systems with optical fiber sensors FBG (Fiber Bragg Grating) are consolidated in the Structural Health Monitoring (SHM) of bridges, static and dynamic nondestructive testing with measurements of deformation, displacement, deflection, temperature and vibrations. A brief introduction to the technology is presented and the fundamentals of optical fiber sensors, their use and comparative advantages over its traditional counterpart. The practice of the FBG sensor application is described. The characteristics of these sensors and measurement graphics are presented. Some key aspects to consider for proper use in the field are mentioned. (author) [es

  9. Optimum wireless sensor deployment scheme for structural health monitoring: a simulation study

    International Nuclear Information System (INIS)

    Liu, Chengyin; Fang, Kun; Teng, Jun

    2015-01-01

    With the rapid advancements in smart sensing technology and wireless communication technology, the wireless sensor network (WSN) offers an alternative solution to structural health monitoring (SHM). In WSNs, dense deployment of wireless nodes aids the identification of structural dynamic characteristics, while data transmission is a significant issue since wireless channels typically have a lower bandwidth and a limited power supply. This paper provides a wireless sensor deployment optimization scheme for SHM, in terms of both energy consumption and modal identification accuracy. A spherical energy model is established to formulate the energy consumption within a WSN. The optimal number of sensors and their locations are obtained through solving a multi-objective function with weighting factors on energy consumption and modal identification accuracy using a genetic algorithm (GA). Simulation and comparison results with traditional sensor deployment methods demonstrate the efficiency of the proposed optimization scheme. (paper)

  10. Time synchronization of a wired sensor network for structural health monitoring

    International Nuclear Information System (INIS)

    Ishikawa, Ken-ichiro; Mita, Akira

    2008-01-01

    This paper introduces a time synchronization system for wired smart sensor networks to be applied to the structural health monitoring of gigantic structures. The jitter of sensor nodes in the wired network depends on the wire length between the origin and the destination of the time synchronization signals. The proposed system can theoretically achieve the accuracy to limit the jitter of sensors within 34 ns by adjusting the timing depending on the wire length, and experimentally showed the jitter of 190 m separation to be within 25 ns. The proposed system uses local area network (LAN) cables and does not require additional cabling for synchronization. Thus the proposed synchronization system can be embedded in the sensor network with minimal cost

  11. Structural and functional social network attributes moderate the association of self-rated health with mental health in midlife and older adults.

    Science.gov (United States)

    Windsor, Tim D; Rioseco, Pilar; Fiori, Katherine L; Curtis, Rachel G; Booth, Heather

    2016-01-01

    Social relationships are multifaceted, and different social network components can operate via different processes to influence well-being. This study examined associations of social network structure and relationship quality (positive and negative social exchanges) with mental health in midlife and older adults. The focus was on both direct associations of network structure and relationship quality with mental health, and whether these social network attributes moderated the association of self-rated health (SRH) with mental health. Analyses were based on survey data provided by 2001 (Mean age = 65, SD = 8.07) midlife and older adults. We used Latent Class Analysis (LCA) to classify participants into network types based on network structure (partner status, network size, contact frequency, and activity engagement), and used continuous measures of positive and negative social exchanges to operationalize relationship quality. Regression analysis was used to test moderation. LCA revealed network types generally consistent with those reported in previous studies. Participants in more diverse networks reported better mental health than those categorized into a restricted network type after adjustment for age, sex, education, and employment status. Analysis of moderation indicated that those with poorer SRH were less likely to report poorer mental health if they were classified into more diverse networks. A similar moderation effect was also evident for positive exchanges. The findings suggest that both quantity and quality of social relationships can play a role in buffering against the negative implications of physical health decline for mental health.

  12. Damage assessment using flexibility and flexibility-based curvature for structural health monitoring

    International Nuclear Information System (INIS)

    Catbas, F N; Gul, M; Burkett, J L

    2008-01-01

    As a result of the recent advances in sensors, information technologies and material science, a considerable amount of research has been conducted in the area of smart infrastructures. While there are many important components of a smart infrastructure, an automated and continuous structural health monitoring (SHM) system is a critical one. SHM is typically used to track and evaluate the performance of a structure, symptoms of operational incidents, anomalies due to deterioration and damage during regular operation as well as after an extreme event. Successful health monitoring applications can be achieved by integrating experimental, analytical and information technologies on real-life operating structures. However, real-life investigations must be backed up by laboratory benchmark studies for validating theory, concepts, and new technologies. For this reason, a physical bridge model is developed to implement SHM methods and technologies. In this study, different aspects of model development are outlined in terms of design considerations, instrumentation, finite element modeling, and simulating damage scenarios. Different damage detection methods are evaluated using the numerical and the physical models. Modal parameter estimation studies are carried out to reliably identify the eigenvalues, eigenvectors and modal scaling from the measurement data. To assess the simulated damage, modal flexibility-based displacements and curvatures are employed. Structural behavior after damage is evaluated by inspecting the deflected shapes obtained using modal flexibility. More localized damage simulations such as stiffness reduction at a joint yield a very subtle stiffness decrease. In this case, the writers use a baseline to identify damage and also investigate the use of curvature as a complementary index. Curvature is advantageous for certain cases where the displacement results do not provide substantial changes. Issues related to using curvature as a damage identification

  13. Fatigue of Ti6Al4V Structural Health Monitoring Systems Produced by Selective Laser Melting

    Directory of Open Access Journals (Sweden)

    Maria Strantza

    2016-02-01

    Full Text Available Selective laser melting (SLM is an additive manufacturing (AM process which is used for producing metallic components. Currently, the integrity of components produced by SLM is in need of improvement due to residual stresses and unknown fracture behavior. Titanium alloys produced by AM are capable candidates for applications in aerospace and industrial fields due to their fracture resistance, fatigue behavior and corrosion resistance. On the other hand, structural health monitoring (SHM system technologies are promising and requested from the industry. SHM systems can monitor the integrity of a structure and during the last decades the research has primarily been influenced by bionic engineering. In that aspect a new philosophy for SHM has been developed: the so-called effective structural health monitoring (eSHM system. The current system uses the design freedom provided by AM. The working principle of the system is based on crack detection by means of a network of capillaries that are integrated in a structure. The main objective of this research is to evaluate the functionality of Ti6Al4V produced by the SLM process in the novel SHM system and to confirm that the eSHM system can successfully detect cracks in SLM components. In this study four-point bending fatigue tests on Ti6Al4V SLM specimens with an integrated SHM system were conducted. Fractographic analysis was performed after the final failure, while finite element simulations were used in order to determine the stress distribution in the capillary region and on the component. It was proven that the SHM system does not influence the crack initiation behavior during fatigue. The results highlight the effectiveness of the eSHM on SLM components, which can potentially be used by industrial and aerospace applications.

  14. Evaluation of the structural health status of the covering of Villa dei Misteri in Pompeii

    International Nuclear Information System (INIS)

    Carpani, B.

    2015-01-01

    'Villa dei Misteri' is one of the most visited monuments of the archaeological area of Pompeii. It is sited just outside the ancient city and takes its name from the superb frescoes cycle depicting ritual mysteries. The ancient masonry structures, dating from the 2. century B.C. to the Vesuvian eruption, are protected from weathering by modern roofs built in various materials (reinforced concrete, timber, steel). After the collapse, in the fall of 2012, of a decayed timber beam, the Suprintendence decided to carry out, in collaboration with ENEA, a detailed survey of all the covering structures to evaluate its health status and to assess the safety condition of the monument. This paper illustrates the research methodology developed, which is based on a multidisciplinary approach including historical research, geometrical and structural surveys, damage assessment based on both in situ and laboratory diagnostic test, UAV (Unmanned Aerial Vehicles) remote sensing to inspect area and coverings not easy to reach in safe, and, as basis for seismic safety assessment, ambient vibration measurement to characterize the dynamic response of the soil and of the most relevant structural components of the 'Villa'. The preliminary results of the first stage of the diagnostic campaign are also presented.

  15. Application of multi-scale (cross-) sample entropy for structural health monitoring

    Science.gov (United States)

    Lin, Tzu-Kang; Liang, Jui-Chang

    2015-08-01

    This study proposes an information-theoretic structural health monitoring (SHM) system based on multi-scale entropy (MSE) and multi-scale cross-sample entropy (MSCE). By measuring the ambient vibration signal from a structure, the damage condition can be rapidly evaluated via MSE analysis. The damage location can then be detected by analyzing the signals of different floors under the same damage condition via MSCE analysis. Moreover, a damage index is proposed to efficiently quantify the SHM process. Unlike some existing SHM methods, no experimental database or numerical model is required. Instead, a reference measurement of the current stage can initiate and launch the SHM system. A numerical simulation of a four-story steel structure is used to verify that the damage location and condition can be detected by the proposed SHM algorithm, and the location can be efficiently quantified by the damage index. A seven-story scaled-down benchmark structure is then employed for experimental verification. Based on the results, the damage condition can be correctly assessed, and average accuracy rates of 63.4 and 86.6% for the damage location can be achieved using the MSCE and damage index methods, respectively. As only the ambient vibration signal is required with a set of initial reference measurements, the proposed SHM system can be implemented practically with low cost.

  16. Structural integration and performance of inter-sectoral public health-related policy networks: An analysis across policy phases

    NARCIS (Netherlands)

    Peters, D. T. J. M.; Raab, J.; Grêaux, K. M.; Stronks, K.; Harting, J.

    2017-01-01

    Background: Inter-sectoral policy networks may be effective in addressing environmental determinants of health with interventions. However, contradictory results are reported on relations between structural network characteristics (i.e., composition and integration) and network performance, such as

  17. Structural integration and performance of inter-sectoral public health-related policy networks : An analysis across policy phases

    NARCIS (Netherlands)

    Peters, Dorothee; Raab, J.; Grêaux, Kimberley M.; Stronks, Karien; Harting, Janneke

    2017-01-01

    Background: Inter-sectoral policy networks may be effective in addressing environmental determinants of health with interventions. However, contradictory results are reported on relations between structure and network characteristics (i.e., composition and integration) and network performance, such

  18. Working Definitions of the Roles and an Organizational Structure in Health Professions Education Scholarship: Initiating an International Conversation

    NARCIS (Netherlands)

    Varpio, L.; Gruppen, L.; Hu, W.; O'Brien, B.; Cate, O. Ten; Humphrey-Murto, S.; Irby, D.M.; Vleuten, C. van der; Hamstra, S.J.; Durning, S.J.

    2017-01-01

    PROBLEM: Health professions education scholarship (HPES) is an important and growing field of inquiry. Problematically, consistent use of terminology regarding the individual roles and organizational structures that are active in this field are lacking. This inconsistency impedes the transferability

  19. Assessment of the effect of visual impairment on mortality through multiple health pathways: structural equation modeling.

    Science.gov (United States)

    Christ, Sharon L; Lee, David J; Lam, Byron L; Zheng, D Diane; Arheart, Kristopher L

    2008-08-01

    To estimate the direct effects of self-reported visual impairment (VI) on health, disability, and mortality and to estimate the indirect effects of VI on mortality through health and disability mediators. The National Health Interview Survey (NHIS) is a population-based annual survey designed to be representative of the U.S. civilian noninstitutionalized population. The National Death Index of 135,581 NHIS adult participants, 18 years of age and older, from 1986 to 1996 provided the mortality linkage through 2002. A generalized linear structural equation model (GSEM) with latent variable was used to estimate the results of a system of equations with various outcomes. Standard errors and test statistics were corrected for weighting, clustering, and stratification. VI affects mortality, when direct adjustment was made for the covariates. Severe VI increases the hazard rate by a factor of 1.28 (95% CI: 1.07-1.53) compared with no VI, and some VI increases the hazard by a factor of 1.13 (95% CI: 1.07-1.20). VI also affects mortality indirectly through self-rated health and disability. The total effects (direct effects plus mediated effects) on the hazard of mortality of severe VI and some VI relative to no VI are hazard ratio (HR) 1.54 (95% CI: 1.28-1.86) and HR 1.23 (95% CI: 1.16-1.31), respectively. In addition to the direct link between VI and mortality, the effects of VI on general health and disability contribute to an increased risk of death. Ignoring the latter may lead to an underestimation of the substantive impact of VI on mortality.

  20. The Electronic Health Record Objective Structured Clinical Examination: Assessing Student Competency in Patient Interactions While Using the Electronic Health Record.

    Science.gov (United States)

    Biagioli, Frances E; Elliot, Diane L; Palmer, Ryan T; Graichen, Carla C; Rdesinski, Rebecca E; Ashok Kumar, Kaparaboyna; Galper, Ari B; Tysinger, James W

    2017-01-01

    Because many medical students do not have access to electronic health records (EHRs) in the clinical environment, simulated EHR training is necessary. Explicitly training medical students to use EHRs appropriately during patient encounters equips them to engage patients while also attending to the accuracy of the record and contributing to a culture of information safety. Faculty developed and successfully implemented an EHR objective structured clinical examination (EHR-OSCE) for clerkship students at two institutions. The EHR-OSCE objectives include assessing EHR-related communication and data management skills. The authors collected performance data for students (n = 71) at the first institution during academic years 2011-2013 and for students (n = 211) at the second institution during academic year 2013-2014. EHR-OSCE assessment checklist scores showed that students performed well in EHR-related communication tasks, such as maintaining eye contact and stopping all computer work when the patient expresses worry. Findings indicated student EHR skill deficiencies in the areas of EHR data management including medical history review, medication reconciliation, and allergy reconciliation. Most students' EHR skills failed to improve as the year progressed, suggesting that they did not gain the EHR training and experience they need in clinics and hospitals. Cross-institutional data comparisons will help determine whether differences in curricula affect students' EHR skills. National and institutional policies and faculty development are needed to ensure that students receive adequate EHR education, including hands-on experience in the clinic as well as simulated EHR practice.

  1. [Nine months German Statutory Health Insurance Structural Reform Law--effects and perspectives].

    Science.gov (United States)

    Engel, H

    1994-02-01

    In 1992 the German Statutory Health Insurance body was in the red by about 9,000 million DM and had the highest membership fees ever since it was created. Costing analysis revealed the following reasons for this enormous deficit: too expensive hospital financing a continually growing number of doctors and dental surgeons unrational drug prescription and supply. Of course, medical progress and demographic development are very significant costing factors. When assessing the impact of the Structural Reform Legislation we must differentiate between purely cost-reducing measures and structural changes. Cutting down the budgets in essential areas of compensation payment and slashing doctor's fees are like putting your foot down on the brake pedal. The statutory health insurance data for the first two quarters showed: doctors +3.4%, dental surgeons -4.3%. Limiting the budget for drugs to about 24,000 million DM and for remedial items to about 4,000 million DM with a possible collective slashing of the fees paid to doctors if these budgets were exceeded, proved to be an effective cost-reducing measure. In the case of drugs costs went down by 20.1% compared with the previous year (1992) due to an halt in prices charged by the drug industry and greater financial participation on the part of the patients. Prescriptions were reduced to a comparatively slight extent (1-2%), but the mode of prescription was much more economical.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Moire-Fringe-Based Fiber Optic Tiltmeter for Structural Health Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Hyun [Seoul National of Technology, Seoul (Korea, Republic of)

    2008-04-15

    This paper presents a novel fiber optic tiltmeter system for the health monitoring of large-size structures. The system is composed of a sensor head, a light control unit and a signal processing unit. The sensing mechanism of the sensor head is based on a novel integration of the moire fringe phenomenon with fiber optics to achieve a robust performance in addition to its immunity to EM interference, easy ratting, and low cost. In this paper, a prototype of the fiber optic tiltmeter system has been developed successfully. A low-cost light control unit has been developed to drive the system's optic and electronic components. From an experimental test, the fiber optic tiltmeter is proven to be a prospective sensor for the monitoring of the tilting angle of civil structure with a good linearity. Finally, the test also successfully demonstrates the performance and the potential of the novel fiber optic tiltmeter system to monitor the health of civil infrastructures.

  3. Electromagnetic-based force sensor for Structural Health Monitoring(SHM)

    International Nuclear Information System (INIS)

    Choi, Man Yong; Park, Hae Won; Park, Jeong Hak; Sam, R.

    2002-01-01

    The demand for maintenance of structural health and safety to acceptable standards poses challenges for research and development of effective technologies for monitoring and measurement of parameters governing safety and health of structures. In this work, an electromagnetic based sensor has been investigated and developed for measuring force in pre-stressed steel cables and tendons. The change in magnetic permeability of a material caused by mechanical stress is exploited to measure force in the material. The sensor consists of a pair of sensing coils and a pair of reference coils. The sensing coils are wound around a stressed material while the reference pair are wound on a dummy specimen of same material as that under stress. When sensing and reference primary coils are excited by same current simultaneously, both the stressed and dummy materials are equally magnetized by the magnetic field generated by the current, and voltage is induced in the sensing and reference secondary coils. The induced voltage in each secondary coil is dependent on a number of factors including the magnetic permeability of its core which is a function of the core magnetizing current, temperature and stress/load. By suitably arranging the sensing and reference coils electro-magnetically, the effects of temperature and magnetizing current on the permeability of a stressed material can be eliminated in the output voltage of the sensor. The output voltage is a function of only the mechanical load in the stressed material, and can be calibrated for determination of force in pre-stressed materials

  4. Structural Health Monitoring of Wind Turbine Blades: Acoustic Source Localization Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Omar Mabrok Bouzid

    2015-01-01

    Full Text Available Structural health monitoring (SHM is important for reducing the maintenance and operation cost of safety-critical components and systems in offshore wind turbines. This paper proposes an in situ wireless SHM system based on an acoustic emission (AE technique. By using this technique a number of challenges are introduced due to high sampling rate requirements, limitations in the communication bandwidth, memory space, and power resources. To overcome these challenges, this paper focused on two elements: (1 the use of an in situ wireless SHM technique in conjunction with the utilization of low sampling rates; (2 localization of acoustic sources which could emulate impact damage or audible cracks caused by different objects, such as tools, bird strikes, or strong hail, all of which represent abrupt AE events and could affect the structural health of a monitored wind turbine blade. The localization process is performed using features extracted from aliased AE signals based on a developed constraint localization model. To validate the performance of these elements, the proposed system was tested by testing the localization of the emulated AE sources acquired in the field.

  5. 'Where Are All the Men?' A Post-Structural Feminist Analysis of a University's Sexual Health Seminar

    Science.gov (United States)

    Quinlan, Margaret M.; Bute, Jennifer J.

    2013-01-01

    Set against the background of efforts to promote sexuality education and sexual health in a university setting, this paper focuses on a sexual health seminar offered at a midwestern US university. Using a post-structural feminist framework, we analysed discourses from qualitative surveys, newspaper coverage and participant observation. We argue…

  6. Valued social roles and measuring mental health recovery: examining the structure of the tapestry.

    Science.gov (United States)

    Hunt, Marcia G; Stein, Catherine H

    2012-12-01

    The complexity of the concept of mental health recovery often makes it difficult to systematically examine recovery processes and outcomes. The concept of social role is inherent within many acknowledged dimensions of recovery such as community integration, family relationships, and peer support and can deepen our understanding of these dimensions when social roles are operationalized in ways that directly relate to recovery research and practice. This paper reviews seminal social role theories and operationalizes aspects of social roles: role investment, role perception, role loss, and role gain. The paper provides a critical analysis of the ability of social role concepts to inform mental health recovery research and practice. PubMed and PsychInfo databases were used for the literature review. A more thorough examination of social role aspects allows for a richer picture of recovery domains that are structured by the concept social roles. Increasing understanding of consumers' investment and changes in particular roles, perceptions of consumers' role performance relative to peers, and consumers' hopes for the future with regards to the different roles that they occupy could generate tangible, pragmatic approaches in addressing complex recovery domains. This deeper understanding allows a more nuanced approach to recovery-related movements in mental health system transformation.

  7. Research culture and capacity in community health services: results of a structured survey of staff.

    Science.gov (United States)

    Friesen, Emma L; Comino, Elizabeth J

    2017-05-01

    Developing research capacity is recognised as an important endeavour. However, little is known about the current research culture, capacity and supports for staff working in community-based health settings. A structured survey of Division of Community Health staff was conducted using the research capacity tool. The survey was disseminated by email and in paper format. Quantitative data were analysed using descriptive statistics. Qualitative data were analysed thematically. In total, 109 usable responses were received, giving a response rate of 26%. Respondents were predominately nurses (n=71, 65.7%), with ~50% reporting post-graduate vocational qualifications. The highest levels of skills or organisational success were in using evidence to plan, promote and guide clinical practice. Most participants were unsure of organisational and team level skills and success at generating research. Few reported recent experience in research-generating activities. Barriers to undertaking research included lack of skills, time and access to external support and funding. Lack of skills and success in accessing external funding and resources to protect research time or to 'buy-in' technical expertise appeared to exacerbate these barriers. Community health staff have limited capacity to generate research with current levels of skill, funding and time. Strategies to increase research capacity should be informed by knowledge of clinicians' research experience and interests, and target development of skills to generate research. Resources and funding are needed at the organisational and team levels to overcome the significant barriers to research generation reported.

  8. Is Internet search better than structured instruction for web-based health education?

    Science.gov (United States)

    Finkelstein, Joseph; Bedra, McKenzie

    2013-01-01

    Internet provides access to vast amounts of comprehensive information regarding any health-related subject. Patients increasingly use this information for health education using a search engine to identify education materials. An alternative approach of health education via Internet is based on utilizing a verified web site which provides structured interactive education guided by adult learning theories. Comparison of these two approaches in older patients was not performed systematically. The aim of this study was to compare the efficacy of a web-based computer-assisted education (CO-ED) system versus searching the Internet for learning about hypertension. Sixty hypertensive older adults (age 45+) were randomized into control or intervention groups. The control patients spent 30 to 40 minutes searching the Internet using a search engine for information about hypertension. The intervention patients spent 30 to 40 minutes using the CO-ED system, which provided computer-assisted instruction about major hypertension topics. Analysis of pre- and post- knowledge scores indicated a significant improvement among CO-ED users (14.6%) as opposed to Internet users (2%). Additionally, patients using the CO-ED program rated their learning experience more positively than those using the Internet.

  9. Structural health monitoring of cylindrical bodies under impulsive hydrodynamic loading by distributed FBG strain measurements

    International Nuclear Information System (INIS)

    Fanelli, Pierluigi; Ubertini, Stefano; Biscarini, Chiara; Jannelli, Elio; Ubertini, Filippo

    2017-01-01

    Various mechanical, ocean, aerospace and civil engineering problems involve solid bodies impacting the water surface and often result in complex coupled dynamics, characterized by impulsive loading conditions, high amplitude vibrations and large local deformations. Monitoring in such problems for purposes such as remaining fatigue life estimation and real time damage detection is a technical and scientific challenge of primary concern in this context. Open issues include the need for developing distributed sensing systems able to operate at very high acquisition frequencies, to be utilized to study rapidly varying strain fields, with high resolution and very low noise, while scientific challenges mostly relate to the definition of appropriate signal processing and modeling tools enabling the extraction of useful information from distributed sensing signals. Building on previous work by some of the authors, we propose an enhanced method for real time deformed shape reconstruction using distributed FBG strain measurements in curved bodies subjected to impulsive loading and we establish a new framework for applying this method for structural health monitoring purposes, as the main focus of the work. Experiments are carried out on a cylinder impacting the water at various speeds, proving improved performance in displacement reconstruction of the enhanced method compared to its previous version. A numerical study is then carried out considering the same physical problem with different delamination damages affecting the body. The potential for detecting, localizing and quantifying this damage using the reconstruction algorithm is thoroughly investigated. Overall, the results presented in the paper show the potential of distributed FBG strain measurements for real time structural health monitoring of curved bodies under impulsive hydrodynamic loading, defining damage sensitive features in terms of strain or displacement reconstruction errors at selected locations along

  10. Structural health monitoring strategy for detection of interlaminar delamination in composite plates

    International Nuclear Information System (INIS)

    Quaegebeur, N; Micheau, P; Masson, P; Maslouhi, A

    2010-01-01

    In this paper, a structural health monitoring strategy for detecting interlaminar delamination in a carbon fiber reinforced polymer structure using Lamb waves is proposed. The delamination is simulated by inserting a Teflon tape between two transverse plies and the Lamb wave generation and measurement is enabled by using piezoceramic elements. The Lamb wave theoretical propagation and through thickness strain distribution are studied, in order to determine the optimal configuration of the final system in terms of mode and frequency selection, and piezoceramic sizing and spacing, for detection of cross-sectional delamination. Pitch and catch measurements are performed by comparing wave propagations for different frequencies and along damaged and undamaged paths of the structure, and the analysis of results is performed using the reassigned short time Fourier transform. It appears that in the low frequency range (below 300 kHz), the A0 mode is sensitive to the damage, while in the high frequency range, S1 and A1 modes are both very sensitive to the damage while the propagation of the S0 mode is not affected very much

  11. Big data and high-performance analytics in structural health monitoring for bridge management

    Science.gov (United States)

    Alampalli, Sharada; Alampalli, Sandeep; Ettouney, Mohammed

    2016-04-01

    Structural Health Monitoring (SHM) can be a vital tool for effective bridge management. Combining large data sets from multiple sources to create a data-driven decision-making framework is crucial for the success of SHM. This paper presents a big data analytics framework that combines multiple data sets correlated with functional relatedness to convert data into actionable information that empowers risk-based decision-making. The integrated data environment incorporates near real-time streams of semi-structured data from remote sensors, historical visual inspection data, and observations from structural analysis models to monitor, assess, and manage risks associated with the aging bridge inventories. Accelerated processing of dataset is made possible by four technologies: cloud computing, relational database processing, support from NOSQL database, and in-memory analytics. The framework is being validated on a railroad corridor that can be subjected to multiple hazards. The framework enables to compute reliability indices for critical bridge components and individual bridge spans. In addition, framework includes a risk-based decision-making process that enumerate costs and consequences of poor bridge performance at span- and network-levels when rail networks are exposed to natural hazard events such as floods and earthquakes. Big data and high-performance analytics enable insights to assist bridge owners to address problems faster.

  12. Autonomous smart sensor network for full-scale structural health monitoring

    Science.gov (United States)

    Rice, Jennifer A.; Mechitov, Kirill A.; Spencer, B. F., Jr.; Agha, Gul A.

    2010-04-01

    The demands of aging infrastructure require effective methods for structural monitoring and maintenance. Wireless smart sensor networks offer the ability to enhance structural health monitoring (SHM) practices through the utilization of onboard computation to achieve distributed data management. Such an approach is scalable to the large number of sensor nodes required for high-fidelity modal analysis and damage detection. While smart sensor technology is not new, the number of full-scale SHM applications has been limited. This slow progress is due, in part, to the complex network management issues that arise when moving from a laboratory setting to a full-scale monitoring implementation. This paper presents flexible network management software that enables continuous and autonomous operation of wireless smart sensor networks for full-scale SHM applications. The software components combine sleep/wake cycling for enhanced power management with threshold detection for triggering network wide tasks, such as synchronized sensing or decentralized modal analysis, during periods of critical structural response.

  13. Crack Propagation Analysis Using Acoustic Emission Sensors for Structural Health Monitoring Systems

    Science.gov (United States)

    Horn, Walter; Steck, James

    2013-01-01

    Aerospace systems are expected to remain in service well beyond their designed life. Consequently, maintenance is an important issue. A novel method of implementing artificial neural networks and acoustic emission sensors to form a structural health monitoring (SHM) system for aerospace inspection routines was the focus of this research. Simple structural elements, consisting of flat aluminum plates of AL 2024-T3, were subjected to increasing static tensile loading. As the loading increased, designed cracks extended in length, releasing strain waves in the process. Strain wave signals, measured by acoustic emission sensors, were further analyzed in post-processing by artificial neural networks (ANN). Several experiments were performed to determine the severity and location of the crack extensions in the structure. ANNs were trained on a portion of the data acquired by the sensors and the ANNs were then validated with the remaining data. The combination of a system of acoustic emission sensors, and an ANN could determine crack extension accurately. The difference between predicted and actual crack extensions was determined to be between 0.004 in. and 0.015 in. with 95% confidence. These ANNs, coupled with acoustic emission sensors, showed promise for the creation of an SHM system for aerospace systems. PMID:24023536

  14. Optimization of PZT ceramic IDT sensors for health monitoring of structures.

    Science.gov (United States)

    Takpara, Rafatou; Duquennoy, Marc; Ouaftouh, Mohammadi; Courtois, Christian; Jenot, Frédéric; Rguiti, Mohamed

    2017-08-01

    Surface acoustic waves (SAW) are particularly suited to effectively monitoring and characterizing structural surfaces (condition of the surface, coating, thin layer, micro-cracks…) as their energy is localized on the surface, within approximately one wavelength. Conventionally, in non-destructive testing, wedge sensors are used to the generation guided waves but they are especially suited to flat surfaces and sized for a given type material (angle of refraction). Additionally, these sensors are quite expensive so it is quite difficult to leave the sensors permanently on the structure for its health monitoring. Therefore we are considering in this study, another type of ultrasonic sensors, able to generate SAW. These sensors are interdigital sensors or IDT sensors for InterDigital Transducer. This paper focuses on optimization of IDT sensors for non-destructive structural testing by using PZT ceramics. The challenge was to optimize the dimensional parameters of the IDT sensors in order to efficiently generate surface waves. Acoustic tests then confirmed these parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Frequency selective surface based passive wireless sensor for structural health monitoring

    International Nuclear Information System (INIS)

    Jang, Sang-Dong; Kang, Byung-Woo; Kim, Jaehwan

    2013-01-01

    Wireless sensor networks or ubiquitous sensor networks are a promising technology giving useful information to people. In particular, the chipless passive wireless sensor is one of the most important developments in wireless sensor technology because it is compact and does not need a battery or chip for the sensor operation. So it has many possibilities for use in various types of sensor system with economical efficiency and robustness in harsh environmental conditions. This sensor uses an electromagnetic resonance frequency or phase angle shift associated with a geometrical change of the sensor tag or an impedance change of the sensor. In this paper, a chipless passive wireless structural health monitoring (SHM) sensor is made using a frequency selective surface (FSS). The cross type FSS is introduced, and its SHM principle is explained. The electromagnetic characteristics of the FSS are simulated in terms of transmission and reflection coefficients using simulation software, and an experimental verification is conducted. The electromagnetic characteristic change of the FSS in the presence of mechanical strain or a structural crack is investigated by means of simulation and experiment. Since large-area structures can be covered by deploying FSS, it is possible to detect the location of any cracks. (paper)

  16. Assessing the value of information for long-term structural health monitoring

    Science.gov (United States)

    Pozzi, Matteo; Der Kiureghian, Armen

    2011-04-01

    In the field of Structural Health Monitoring, tests and sensing systems are intended as tools providing diagnoses, which allow the operator of the facility to develop an efficient maintenance plan or to require extraordinary measures on a structure. The effectiveness of these systems depends directly on their capability to guide towards the most optimal decision for the prevailing circumstances, avoiding mistakes and wastes of resources. Though this is well known, most studies only address the accuracy of the information gained from sensors without discussing economic criteria. Other studies evaluate these criteria separately, with only marginal or heuristic connection with the outcomes of the monitoring system. The concept of "Value of Information" (VoI) provides a rational basis to rank measuring systems according to a utility-based metric, which fully includes the decision-making process affected by the monitoring campaign. This framework allows, for example, an explicit assessment of the economical justifiability of adopting a sensor depending on its precision. In this paper we outline the framework for assessing the VoI, as applicable to the ranking of competitive measuring systems. We present the basic concepts involved, highlight issues related to monitoring of civil structures, address the problem of non-linearity of the cost-to-utility mapping, and introduce an approximate Monte Carlo approach suitable for the implementation of time-consuming predictive models.

  17. A time reversal damage imaging method for structure health monitoring using Lamb waves

    International Nuclear Information System (INIS)

    Zhang Hai-Yan; Cao Ya-Ping; Sun Xiu-Li; Chen Xian-Hua; Yu Jian-Bo

    2010-01-01

    This paper investigates the Lamb wave imaging method combining time reversal for health monitoring of a metallic plate structure. The temporal focusing effect of the time reversal Lamb waves is investigated theoretically. It demonstrates that the focusing effect is related to the frequency dependency of the time reversal operation. Numerical simulations are conducted to study the time reversal behaviour of Lamb wave modes under broadband and narrowband excitations. The results show that the reconstructed time reversed wave exhibits close similarity to the reversed narrowband tone burst signal validating the theoretical model. To enhance the similarity, the cycle number of the excited signal should be increased. Experiments combining finite element model are then conducted to study the imaging method in the presence of damage like hole in the plate structure. In this work, the time reversal technique is used for the recompression of Lamb wave signals. Damage imaging results with time reversal using broadband and narrowband excitations are compared to those without time reversal. It suggests that the narrowband excitation combined time reversal can locate and determine the size of structural damage more precisely, but the cycle number of the excited signal should be chosen reasonably

  18. Combination of digital signal processing methods towards an improved analysis algorithm for structural health monitoring.

    Science.gov (United States)

    Pentaris, Fragkiskos P.; Makris, John P.

    2013-04-01

    In Structural Health Monitoring (SHM) is of great importance to reveal valuable information from the recorded SHM data that could be used to predict or indicate structural fault or damage in a building. In this work a combination of digital signal processing methods, namely FFT along with Wavelet Transform is applied, together with a proposed algorithm to study frequency dispersion, in order to depict non-linear characteristics of SHM data collected in two university buildings under natural or anthropogenic excitation. The selected buildings are of great importance from civil protection point of view, as there are the premises of a public higher education institute, undergoing high use, stress, visit from academic staff and students. The SHM data are collected from two neighboring buildings that have different age (4 and 18 years old respectively). Proposed digital signal processing methods are applied to the data, presenting a comparison of the structural behavior of both buildings in response to seismic activity, weather conditions and man-made activity. Acknowledgments This work was supported in part by the Archimedes III Program of the Ministry of Education of Greece, through the Operational Program "Educational and Lifelong Learning", in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) » and is co-financed by the European Union (European Social Fund) and Greek National Fund.

  19. Sub-Frequency Interval Approach in Electromechanical Impedance Technique for Concrete Structure Health Monitoring

    Directory of Open Access Journals (Sweden)

    Bahador Sabet Divsholi

    2010-12-01

    Full Text Available The electromechanical (EM impedance technique using piezoelectric lead zirconate titanate (PZT transducers for structural health monitoring (SHM has attracted considerable attention in various engineering fields. In the conventional EM impedance technique, the EM admittance of a PZT transducer is used as a damage indicator. Statistical analysis methods such as root mean square deviation (RMSD have been employed to associate the damage level with the changes in the EM admittance signatures, but it is difficult to determine the location of damage using such methods. This paper proposes a new approach by dividing the large frequency (30–400 kHz range into sub-frequency intervals and calculating their respective RMSD values. The RMSD of the sub-frequency intervals (RMSD-S will be used to study the severity and location of damage. An experiment is carried out on a real size concrete structure subjected to artificial damage. It is observed that damage close to the PZT changes the high frequency range RMSD-S significantly, while the damage far away from the PZT changes the RMSD-S in the low frequency range significantly. The relationship between the frequency range and the PZT sensing region is also presented. Finally, a damage identification scheme is proposed to estimate the location and severity of damage in concrete structures.

  20. A probabilistic approach for optimal sensor allocation in structural health monitoring

    International Nuclear Information System (INIS)

    Azarbayejani, M; Reda Taha, M M; El-Osery, A I; Choi, K K

    2008-01-01

    Recent advances in sensor technology promote using large sensor networks to efficiently and economically monitor, identify and quantify damage in structures. In structural health monitoring (SHM) systems, the effectiveness and reliability of the sensor network are crucial to determine the optimal number and locations of sensors in SHM systems. Here, we suggest a probabilistic approach for identifying the optimal number and locations of sensors for SHM. We demonstrate a methodology to establish the probability distribution function that identifies the optimal sensor locations such that damage detection is enhanced. The approach is based on using the weights of a neural network trained from simulations using a priori knowledge about damage locations and damage severities to generate a normalized probability distribution function for optimal sensor allocation. We also demonstrate that the optimal sensor network can be related to the highest probability of detection (POD). The redundancy of the proposed sensor network is examined using a 'leave one sensor out' analysis. A prestressed concrete bridge is selected as a case study to demonstrate the effectiveness of the proposed method. The results show that the proposed approach can provide a robust design for sensor networks that are more efficient than a uniform distribution of sensors on a structure