Geometric approach to vibrational control of singularly perturbed systems

We extend the theory of vibrational stabilizability to systems with fast and slow variables. The mathematical tools for establishing corresponding results are the persistence theory of normally hyperbolic invariant manifolds, the averaging theory and appropriate transformations. At the same time we introduce modified concepts of vibrational stabilizability compared with the 'classical' definitions

New tools of the trade? The potential and pitfalls of ’Machine Learning’ and ’DAGs’ to model origin-destination data

This paper explores the potential for emerging methods Machine Learning and Directed Acyclic Graphs (DAGs) to be applied to transport modelling at the origin-destination (OD) level. OD data is inherently spatial and is complex, due to the multitude of ways of allocating geographic attributes to the OD pairs (e.g. buffers and intersections with geographic representations of OD data generated using straight desire lines, shortest path algorithms or probabilistic routing). This makes their analysis an interesting geocomputational challenge, seldom tackled by geographers. The application of Machine Learning and DAG methods, developed in other fields, to this geographical data holds great potential to improve the ability to infer causality in mode split from OD data. However, there are also pitfalls to using these methods which can be black boxes, even if the code is open source, if the analyst does not understand what they are doing with the data. Based on the work we discuss ways to ensure new methods in the field are used wisely and set-out next steps for our own research

Wide band frequency tracker performance and design of an all angle laser Doppler optical homodyne receiver, ground wind and wind tunnel measurements program, volume 2 Final report

Analysis and measurement of characteristics of wide band frequency trackers and design and fabrication of all angle laser Doppler velocimete

Versioning of Digital Objects in a Fedora-based Repository

This presentation gives an overview on the complex versioning re-quirements for digital objects in the scope of the project eSciDoc and discusses our solution based on the flexible repository architecture Fedora. It describes the conceptual background of how the eSciDoc infrastructure handles versioning of digital objects. Versioning and object identification are strongly interwoven concepts. Therefore, the unique identification of objects and their versions are discussed as well

Rejection of mismatched disturbances for systems with input delay via a predictive extended state observer

[EN] The problem of output stabilization and disturbance rejection for input-delayed systems is tackled in this work. First, a suitable transformation is introduced to translate mismatched disturbances into an equivalent input disturbance. Then, an extended state observer is combined with a predictive observer structure to obtain a future estimation of both the state and the disturbance. A disturbance model is assumed to be known but attenuation of unmodeled components is also considered. The stabilization is proved via Lyapunov-Krasovskii functionals, leading to sufficient conditions in terms of linear matrix inequalities for the closed-loop analysis and parameter tuning. The proposed strategy is illustrated through a numerical example.PROMETEOII/2013/004; Conselleria d'Educacio; Generalitat Valenciana, Grant/Award Number: TIN2014-56158-C4-4-P-AR; Ministerio de Economia y Competitividad, Grant/Award Number: FPI-UPV 2014; Universitat Politecnica de ValenciaSanz Diaz, R.; García Gil, PJ.; Fridman, E.; Albertos Pérez, P. (2018). Rejection of mismatched disturbances for systems with input delay via a predictive extended state observer. International Journal of Robust and Nonlinear Control. 28(6):2457-2467. https://doi.org/10.1002/rnc.4027S24572467286Stability and Stabilization of Systems with Time Delay. (2011). IEEE Control Systems, 31(1), 38-65. doi:10.1109/mcs.2010.939135Fridman, E. (2014). Introduction to Time-Delay Systems. Systems & Control: Foundations & Applications. doi:10.1007/978-3-319-09393-2Watanabe, K., & Ito, M. (1981). A process-model control for linear systems with delay. IEEE Transactions on Automatic Control, 26(6), 1261-1269. doi:10.1109/tac.1981.1102802Astrom, K. J., Hang, C. C., & Lim, B. C. (1994). A new Smith predictor for controlling a process with an integrator and long dead-time. IEEE Transactions on Automatic Control, 39(2), 343-345. doi:10.1109/9.272329Matausek, M. R., & Micic, A. D. (1996). A modified Smith predictor for controlling a process with an integrator and long dead-time. IEEE Transactions on Automatic Control, 41(8), 1199-1203. doi:10.1109/9.533684García, P., & Albertos, P. (2008). A new dead-time compensator to control stable and integrating processes with long dead-time. Automatica, 44(4), 1062-1071. doi:10.1016/j.automatica.2007.08.022Normey-Rico, J. E., & Camacho, E. F. (2009). Unified approach for robust dead-time compensator design. Journal of Process Control, 19(1), 38-47. doi:10.1016/j.jprocont.2008.02.003Manitius, A., & Olbrot, A. (1979). Finite spectrum assignment problem for systems with delays. IEEE Transactions on Automatic Control, 24(4), 541-552. doi:10.1109/tac.1979.1102124Artstein, Z. (1982). Linear systems with delayed controls: A reduction. IEEE Transactions on Automatic Control, 27(4), 869-879. doi:10.1109/tac.1982.1103023Krstic, M. (2008). Lyapunov tools for predictor feedbacks for delay systems: Inverse optimality and robustness to delay mismatch. Automatica, 44(11), 2930-2935. doi:10.1016/j.automatica.2008.04.010Léchappé, V., Moulay, E., Plestan, F., Glumineau, A., & Chriette, A. (2015). New predictive scheme for the control of LTI systems with input delay and unknown disturbances. Automatica, 52, 179-184. doi:10.1016/j.automatica.2014.11.003Sanz, R., Garcia, P., & Albertos, P. (2016). Enhanced disturbance rejection for a predictor-based control of LTI systems with input delay. Automatica, 72, 205-208. doi:10.1016/j.automatica.2016.05.019Basturk, H. I., & Krstic, M. (2015). Adaptive sinusoidal disturbance cancellation for unknown LTI systems despite input delay. Automatica, 58, 131-138. doi:10.1016/j.automatica.2015.05.013Basturk, H. I. (2017). Cancellation of unmatched biased sinusoidal disturbances for unknown LTI systems in the presence of state delay. Automatica, 76, 169-176. doi:10.1016/j.automatica.2016.10.006Sanz, R., Garcia, P., Albertos, P., & Zhong, Q.-C. (2016). Robust controller design for input-delayed systems using predictive feedback and an uncertainty estimator. International Journal of Robust and Nonlinear Control, 27(10), 1826-1840. doi:10.1002/rnc.3639Mondie, S., & Michiels, W. (2003). Finite spectrum assignment of unstable time-delay systems with a safe implementation. IEEE Transactions on Automatic Control, 48(12), 2207-2212. doi:10.1109/tac.2003.820147Zhong, Q.-C. (2004). On Distributed Delay in Linear Control Laws—Part I: Discrete-Delay Implementations. IEEE Transactions on Automatic Control, 49(11), 2074-2080. doi:10.1109/tac.2004.837531Zhou, B., Lin, Z., & Duan, G.-R. (2012). Truncated predictor feedback for linear systems with long time-varying input delays. Automatica, 48(10), 2387-2399. doi:10.1016/j.automatica.2012.06.032Zhou, B., Li, Z.-Y., & Lin, Z. (2013). On higher-order truncated predictor feedback for linear systems with input delay. International Journal of Robust and Nonlinear Control, 24(17), 2609-2627. doi:10.1002/rnc.3012Besançon G Georges D Benayache Z Asymptotic state prediction for continuous-time systems with delayed input and application to control IEEE 2007 Kos, GreeceNajafi, M., Hosseinnia, S., Sheikholeslam, F., & Karimadini, M. (2013). Closed-loop control of dead time systems via sequential sub-predictors. International Journal of Control, 86(4), 599-609. doi:10.1080/00207179.2012.751627Léchappé V Moulay E Plestan F Dynamic observation-prediction for LTI systems with a time-varying delay in the input IEEE 2016 Las Vegas, NVCacace, F., Conte, F., Germani, A., & Pepe, P. (2016). Stabilization of strict-feedback nonlinear systems with input delay using closed-loop predictors. International Journal of Robust and Nonlinear Control, 26(16), 3524-3540. doi:10.1002/rnc.3517Mazenc, F., & Malisoff, M. (2017). Stabilization of Nonlinear Time-Varying Systems Through a New Prediction Based Approach. IEEE Transactions on Automatic Control, 62(6), 2908-2915. doi:10.1109/tac.2016.2600500Guo, L., & Chen, W.-H. (2005). Disturbance attenuation and rejection for systems with nonlinearity via DOBC approach. International Journal of Robust and Nonlinear Control, 15(3), 109-125. doi:10.1002/rnc.978Fridman, E. (2003). Output regulation of nonlinear systems with delay. Systems & Control Letters, 50(2), 81-93. doi:10.1016/s0167-6911(03)00131-2Isidori, A., & Byrnes, C. I. (1990). Output regulation of nonlinear systems. IEEE Transactions on Automatic Control, 35(2), 131-140. doi:10.1109/9.45168Ding, Z. (2003). 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hi2-1, A QTL which improves harvest index, earliness and alters metabolite accumulation of processing tomatoes

Harvest index, defined as the ratio of reproductive yield to total plant biomass, and early ripening are traits with important agronomic value in processing tomatoes. The Solanum pennellii introgression-line (IL) population shows variation for harvest index and earliness. Most of the QTL mapped for these traits display negative agronomic effects; however, hi2-1 is a unique QTL displaying improved harvest index and earliness. This introgression was tested over several years and under different genetic backgrounds. Thirty-one nearly isogenic sub-lines segregating for the 18 cM TG33–TG276 interval were used for fine mapping of this multi-phenotypic QTL. Based on this analysis the phenotypic effects for plant weight, Brix, total yield and earliness were co-mapped to the same region. In a different mapping experiment these sub-lines were tested as heterozygotes in order to map the harvest index QTL which were only expressed in the heterozygous state. These QTL mapped to the same candidate region, suggesting that hi2-1 is either a single gene with pleiotropic effects or represents linked genes independently affecting these traits. Metabolite profiling of the fruit pericarp revealed that a number of metabolic QTL co-segregate with the harvest index trait including those for important transport assimilates such as sugars and amino acids. Analysis of the flowering pattern of these lines revealed induced flowering at IL2-1 plants, suggest that hi2-1 may also affect harvest index and early ripening by changing plant architecture and flowering rate

Epidemiology of sports-related injuries in children and youth presenting to Canadian emergency departments from 2007–2010

BACKGROUND: Although injuries related to sports and recreation represent a significant burden to children and youth, few studies have examined the descriptive epidemiology of sports-related injury since 2005, and some sports such as ringette have not been evaluated to date. The primary purpose of this study was to provide the descriptive epidemiology of sports-related injuries treated in emergency departments for children and youth aged 5 – 19. METHODS: A retrospective data analysis was performed using data from the Canadian Hospitals Injury Reporting and Prevention Program [CHIRPP] from fiscal years (April – March) 2007/08 to 2009/10. CHIRPP is a computerized information system designed by the Public Health Agency of Canada that collects information about injuries to people evaluated in emergency departments across 11 pediatric hospitals and 5 general hospitals in Canada. Thirteen sports or activities were analyzed (baseball, basketball, cycling, football, ice hockey, lacrosse, ringette, rugby, skiing, sledding, snowboarding, soccer, and volleyball). Descriptive statistics, including frequency by sport, age and sex, as well as the percent of concussions within each sport were calculated. RESULTS: Out of a total of 56, 691 reported sports and recreational injuries, soccer accounted for the largest proportion of injuries with 11,941 reported cases over the 3 year time period. Of these, approximately 30% were fractures. The 10 – 14 year age group reported the greatest proportion of injuries in 10 out of the 13 sports analyzed. In addition, males reported a greater number of overall injuries than females in 11 out of the 13 sports analyzed. The largest percentage of concussions was reported in ringette; these injuries accounted for 17.1% of overall injuries within this sport. CONCLUSIONS: Injury prevention programs in Canada should focus on improving evidence-based programs to reduce the burden of injuries in all sports