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Distributed scheduling of measurements in a sensor network for parameter estimation of spatio-temporal systems

-668. Uciński, D. (2000). Optimal selection of measurement locations for parameter estimation in distributed processes, International Journal of Applied Mathematics and Computer Science 10(2): 357-379. Uciński, D. (2004). Optimal Measurement Methods for Distributed Parameter System Identification, CRC Press, Boca Raton, FL. Uciński, D. (2012). Sensor network scheduling for identification of spatially distributed processes, International Journal of Applied Mathematics and Computer Science 22(1): 25-40, DOI: 10.2478/v10006

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IoT Sensing Networks for Gait Velocity Measurement

Abstract

Gait velocity has been considered the sixth vital sign. It can be used not only to estimate the survival rate of the elderly, but also to predict the tendency of falling. Unfortunately, gait velocity is usually measured on a specially designed walk path, which has to be done at clinics or health institutes. Wearable tracking services using an accelerometer or an inertial measurement unit can measure the velocity for a certain time interval, but not all the time, due to the lack of a sustainable energy source. To tackle the shortcomings of wearable sensors, this work develops a framework to measure gait velocity using distributed tracking services deployed indoors. Two major challenges are tackled in this paper. The first is to minimize the sensing errors caused by thermal noise and overlapping sensing regions. The second is to minimize the data volume to be stored or transmitted. Given numerous errors caused by remote sensing, the framework takes into account the temporal and spatial relationship among tracking services to calibrate the services systematically. Consequently, gait velocity can be measured without wearable sensors and with higher accuracy. The developed method is built on top of WuKong, which is an intelligent IoT middleware, to enable location and temporal-aware data collection. In this work, we present an iterative method to reduce the data volume collected by thermal sensors. The evaluation results show that the file size is up to 25% of that of the JPEG format when the RMSE is limited to 0.5◦.

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An Interval Estimator for Chlorine Monitoring in Drinking Water Distribution Systems Under Uncertain System Dynamics, Inputs and Chlorine Concentration Measurement Errors

parameters in quantity models of water supply and distribution systems, Automatisierungstechnik 43(2): 77-84. Brdys, M.A. and Chen, K. (1996). Joint estimation of states and parameters of integrated quantity and quality models of dynamic water supply and distribution systems, Proceedings of the 13th IFAC World Congress, San Francisco, CA, Vol. 1, pp. 759-762. Brdys, M.A. and Łangowski, R. (2008). Interval estimator for chlorine monitoring in drinking water distribution systems under uncertain system dynamics, inputs and state measurement

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A Three–Level Aggregation Model for Evaluating Software Usability by Fuzzy Logic

References Albert, W. and Tullis, T. (2013). Measuring the User Experience, Collecting, Analyzing, and Presenting Usability Metrics (Interactive Technologies), 2nd Edition , Elsevier, Amsterdam. Allen, I.E. and Seaman, C. (2007). Likert scales and data analyses, Technical report , QP-Quality Progress, http://asq.org/quality-progress/2007/07/statistics/likert-scales-and-data-analyses.html . Bavdaž, M. (2010). Sources of measurement errors in business surveys, Journal of Official Statistics 26 (1): 25–42. Bavdaž, M., Biffignandi, S

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System matrix computation for iterative reconstruction algorithms in SPECT based on direct measurements

System matrix computation for iterative reconstruction algorithms in SPECT based on direct measurements

A method for system matrix calculation in the case of iterative reconstruction algorithms in SPECT was implemented and tested. Due to a complex mathematical description of the geometry of the detector set-up, we developed a method for system matrix computation that is based on direct measurements of the detector response. In this approach, the influence of the acquisition equipment on the image formation is measured directly. The objective was to obtain the best quality of reconstructed images with respect to specified measures. This is indispensable in order to be able to perform reliable quantitative analysis of SPECT images. It is also especially important in non-hybrid gamma cameras, where not all physical processes that disturb image acquisition can be easily corrected. Two experiments with an 131 I point source placed at different distances from the detector plane were performed allowing the detector response to be acquired as a function of the point source distance. An analytical Gaussian function was fitted to the acquired data in both the one- and the two-dimensional case. A cylindrical phantom filled with a water solution of 131 I containing a region of "cold" spheres as well as a uniform solution (without any spheres) was used to perform algorithm evaluation. The reconstructed images obtained by using four different of methods system matrix computation were compared with those achieved using reconstruction software implemented in the gamma camera. The contrast of the spheres and uniformity were compared for each reconstruction result and also with the ranges of those values formulated by the AAPM (American Association of Physicists in Medicine). The results show that the implementation of the OSEM (Ordered Subsets Expectation Maximization) algorithm with a one-dimensional fit to the Gaussian CDR (Collimator-Detector Response) function provides the best results in terms of adopted measures. However, the fit of the two-dimensional function also gives satisfactory results. Furthermore, the CDR function has the potential to be applied to a fully 3D OSEM implementation. The lack of the CDR in system matrix calculation results in a very noisy image that cannot be used for diagnostic purposes.

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The Effect of Elastic and Inelastic Scattering on Electronic Transport in Open Systems

Abstract

The purpose of this study is to apply the distribution function formalism to the problem of electronic transport in open systems, and to numerically solve the kinetic equation with a dissipation term. This term is modeled within the relaxation time approximation and contains two parts, corresponding to elastic or inelastic processes. The collision operator is approximated as a sum of the semi-classical energy dissipation term and the momentum relaxation term, which randomizes the momentum but does not change the energy. As a result, the distribution of charge carriers changes due to the dissipation processes, which has a profound impact on the electronic transport through the simulated region discussed in terms of the current–voltage characteristics and their modification caused by the scattering. Measurements of the current–voltage characteristics for titanium dioxide thin layers are also presented, and compared with the results of numerical calculations.

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Synergetic Control for HVAC System Control and VAV Box Fault Compensation

, International Journal of Applied Mathematics and Computer Science 24 (4): 809–820, DOI: 10.2478/amcs-2014-0060. Chen, J. and Patton, R.J. (2012). Robust Model-based Fault Diagnosis for Dynamic Systems , Springer Science & Business Media, Norwell, MA. Chinde, V., Kosaraju, K., Kelkar, A., Pasumarthy, R., Sarkar, S. and Singh, N. (2017). A passivity-based power-shaping control of building HVAC systems, Journal of Dynamic Systems, Measurement, and Control 139 (11): 111007. Darure, T., Yamé, J.-J. and Hamelin, F. (2016). Model-based fault-tolerant control

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Comparison of clinical data based on limits of agreement

References Altman D., Bland J. (1983): Measurement in medicine: the analysis of method comparison studies. Statistician 32: 307-17. Bland J., Altman D. (2007): Agreement Between Methods of Measurement with Multiple Observations Per Individual. Journal of Biopharmaceutical Statistics 17: 571-582. Bland J., Altman D. (2003): Applying the Right Statistics: Analyses of Measurement Studies. Ultrasound in Obstetrics and Gynecology 22: 85-93. Bland J., Altman D. (1999): Measuring agreement in

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A survey of subpixel edge detection methods for images of heat-emitting metal specimens

-11822. Fabija´nska, A. and Sankowski, D. (2009). Computer vision system for high temperature measurements of surface properties, Machine Vision and Applications 20 (6): 411-421. Fabija´nska, A. and Sankowski, D. (2010). Edge detection with sub-pixel accuracy in images of molten metals, IEEE International Conference on Imaging Systems and Techniques, Thessaloniki, Greece , pp. 186-191. Gocławski, J., Sekulska-Nalewajko, J., Gajewska, E. and Wielanek, M. (2009). An automatic segmentation method for scanned images of wheat root systems with

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On-line wavelet estimation of Hammerstein system nonlinearity

measurement sequence, IEEE Signal Processing Letters   16 (9): 762-765. Nešić, D. and Mareels, I. M. Y. (1998). Dead-beat control of simple Hammerstein models, IEEE Transactions on Automatic Control   43 (8): 1184-1188. Niedźwiecki, M. (1988). Functional series modeling approach to identification of nonstationary stochastic systems, IEEE Transactions on Automatic Control   33 (10): 955-961. Nordsjo, A. and Zetterberg, L. (2001). Identification of certain time-varying nonlinear Wiener and

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