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(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. ; [EN] While wind turbine (WT) power capacities continue to increase and new offshore developments are being deployed, operation and maintenance (O&M) costs continue to rise, becoming the center of attention in the wind energy sector. The electric generator is among the top three contributors to failure rates and downtime of WTs, where the doubly fed induction generator (DFIG) is the dominant technology among variable speed WTs. Thus, the early detection of generator faults, which can be achieved through predictive maintenance, is vital in order to reduce O&M costs. The goal of this paper is to analyze a long-term monitoring campaign of an in-service WT equipped with a DFIG. A novel method named the harmonic order tracking analysis is used with two main objectives: first, to facilitate the data interpretation for non-trained maintenance personnel, and second, to reduce the amount of data that must be stored and transferred for the diagnosis of the DFIG. This method is applied and validated for the first time on an operating WT. ; This work was supported in part by the Agreement signed between the UCLM and the Council of Albacete to promote research in the Campus of Albacete, and in part by the European Union Horizon 2020 Research and Innovation Programme through the Marie Sklodowska-Curie Grant (AWESOME Project) under Grant 642108. The authors would like to thank Ingeteam Power Technology S.A. UP Service, part of the AWESOME Project Consortium providing the wind turbine data. ; Artigao, E.; Sapena-Bano, A.; Honrubia-Escribano, A.; Martinez-Roman, J.; Puche-Panadero, R.; Gómez-Lázaro, E. (2019). Long-Term Operational Data Analysis of an In-Service Wind ...

In the implementation of comparative analysis of the application of methods of harmonic weights and integrated economic and statistical calculations in the analysis of socio-economic security characteristics, the priority is given to the method of integrated economic and statistical calculations. When predicting the characteristics of socio-economic security by the method of integrated economic and statistical calculations, their absolute levels or the dynamics of their growth are used. The use of the absolute values of socio-economic security characteristics in forecasting seems more appropriate, as it is possible to solve a number of problems of the method — to identify the levels of factors and factors K_ xi in the lead period.

Since its introduction in the mid 90ies, the Terrestrial Trunked Radio (TETRA) standard for digital radio broadcast has been deployed in most European and Asian government networks and public safety networks. The underlying Adaptive Code-Excitation Linear Prediction scheme employs adaptive code books which are optimized for human speech. However, harmonic distortions of the hardware are amplified as well, which we will show via spectrograms and frequency analysis. While many studies indicate that human perception neglects these distortions up to a Total Harmonic Distortion of about 1%, their impact on Automatic Speech Recognition (ASR) can be dramatic. In this paper, we demonstrate this effect on a strong recognition system for German broadcast news, using a dedicated fire fighter radio transmitter. We will dissect the influence of the hardware and the software components by analysing the word error rate, typical word substitutions and changes in the extracted features. We also suggest countermeasures to obtain a stronger ASR system in this setting.

1 6 2013 ; S ; For an arbitrary open subset U subset of R-d or U subset of C-d and a continuous function v : U ->]0,infinity[ we show that the space h(v0) (U) of weighed harmonic functions is almost isometric to a (closed) subspace of c(0), thus extending a theorem due to Bonet and Wolf for spaces of holomorphic functions H-v0 (U) on open sets U subset of C-d. Inspired by recent work of Boyd and Rueda, we characterize in terms of the extremal points of the dual of h(v0) (U) when h(v0) (U) is isometric to a subspace of c(0). Some geometric conditions on an open set U subset of C-d and convexity conditions on a weight v on U are given to ensure that neither H-v0 (U) nor h(v0) (U) are rotund. The authors are grateful to J. Bonet for a lot of ideas and discussions during all this work. They are also indebted to P. Rueda, who besides giving them some references provided them some unpublished work which has inspired a big part of this paper. They also thank M. Maestre for his careful reading of the paper and helpful discussions. Finally, they thank the referees for the careful analysis of the paper and the important suggestions which they gave us. The research of the first author was supported by MICINN and FEDER, Project MTM2010-15200. The research of both authors is partially supported by Programa de Apoyo a la Investigacion y Desarrollo de la UPV PAID-06-12. Jorda Mora, E.; Zarco García, AM. (2013). Isomorphisms on weighed Banach spaces of harmonic and holomorphic functions. Journal of Function Spaces and Applications. 2013:1-6. https://doi.org/10.1155/2013/178460 Bierstedt, K. D., Bonet, J., & Galbis, A. (1993). Weighted spaces of holomorphic functions on balanced domains. The Michigan Mathematical Journal, 40(2), 271-297. doi:10.1307/mmj/1029004753 Bonet, J., Dománski, P., & Lindström, M. (1999). Essential Norm and Weak Compactness of Composition Operators on Weighted Banach Spaces of Analytic Functions. Canadian Mathematical Bulletin, 42(2), 139-148. doi:10.4153/cmb-1999-016-x Bonet, J., Domański, P., ...

Розглянуто причини виникнення вищих гармонійних складових і їх наслідки на роботу електрообладнання. Проблема вищих гармонік обумовлена, в першу чергу, прогресом в області силової перетворювальної техніки військових об'єктів, який привів до більш широкого впровадження у промислове електропостачання потужних вентильних перетворювачів, електродугових сталеплавильних печей, зварювальні апарати, які характеризуються в процесі своєї експлуатації появою вольт-амперних характеристик. Розглянуто різні методики розрахунку вищих гармонік в електричних мережах, які засновані на рішенні диференціальних рівнянь, теорії ланцюгів, велику увагу приділено аналізу методики розрахунку несинусоїдальних режимів роботи розподільних мереж енергосистеми, розглянуто основні допущення, прийняті при використанні даного алгоритму, та етапи розрахунку з даної методики. Зроблені висновки про те, які саме завдання дозволяє вирішувати розглянута методика. ; Рассмотрены причины возникновения высших гармонических составляющих и их последствия на работу электрооборудования. Проблема высших гармоник обусловлена, в первую очередь, прогрессом в области силовой преобразовательной техники военных объектов, который привел к более широкому внедрению в промышленное электроснабжение мощных вентильных преобразователей, электродуговых сталеплавильных печей, сварочные аппараты, которые характеризуются в процессе своей эксплуатации появлением вольт-амперных характеристик. Рассмотрены различные методики расчета высших гармоник в электрических сетях, которые основаны на решении дифференциальных уравнений, теории цепей, большое внимание уделено анализу методики расчета несинусоидальных режимов работы распределительных сетей энергосистемы, рассмотрены основные допущения, принимаемые при использовании данного алгоритма, и этапы расчета по данной методики. Сделаны выводы о том, какие именно задачи позволяет решать рассмотренная методика. ; Reasons of origin of higher harmonic constituents and their consequence are considered to work of electrical equipment. The problem of ultraharmonics is conditioned, above all things, by progress in area of power inverter technique of military objectives, which resulted in more wide introduction in the industrial power supply of powerful valve transformers, elektrodugovykh steelsmelting stoves, welding vehicles which are characterized in the process of the exploitation appearance of volt-ampere. The different methods of calculation of ultraharmonics are considered in electric networks, which are based on the decision of differential equalizations, theory of chains, large attention is spared the analysis of method of calculation of the nonsinusoidal modes of operations of distributive networks of grid, basic assumptions, accepted at the use of this algorithm, and stages of calculation, are considered to on this method. Conclusions are done about that, which one tasks the considered method allows to decide.

In this study, polarization second harmonic generation (SHG) imaging is used and data analysis is developed to gain contrast and to discriminate with pixel resolution, in the same image, SHG source architectures. We use mammalian tissue in which both skeletal muscle and fibrilar collagen can be found. The images are fitted point by point using an algorithm based on a biophysical model, where the coefficient of determination is utilized as a filtering mechanism. For the whole image we retrieve for every pixel, the effective orientation, θe, of the SHG active structures. As a result a new image is formed which its contrast depends on the values of θe. Collagen presented in the forward direction for a predefined region of interest (ROI), peak distribution of angles θe centered in the region of ∼45°, while muscle in the region of ∼65°. Consequently, collagen and muscle are represented in different colors in the same image. Thus, here we show that it is possible to gain contrast and to discriminate between collagen and muscle without the use of any exogenous labeling or any co-localization with fluorescence imaging. © 2009 SPIE-OSA. ; This work is supported by the Generalitat de Catalunya and by the Spanish government grant TEC2006-12654 SICO. Authors also acknowledge The Centre Innovacio i Desenvolupament Empresarial-CIDEM (RDITSCON07-1-0006), Grupo Ferrer and the European Regional Development Fund. This research has been partially supported by Fundació Cellex Barcelona. ; Peer Reviewed

Vibration-induced solder joint fatigue is a main reliability concern for aerospace and military industries whose electronic equipment used in the field is required to remain functional under harsh loadings. Due to the RoHS directive which eventually will prevent lead from being utilized in electronic systems, there is a need for a better understanding of lead-free mechanical behavior under vibration conditions. This study reports the durability of Sn3.0Ag0.5Cu (SAC305) solder joints subjected to harmonic solicitations at three specific temperatures (-55°C, 20°C and 105°C) and random vibrations at ambient temperature (20°C). A test assembly was designed and consisted in a single daisy-chained 1152 I/O ball grid array (FBGA1152) package assembled on a flame retardant (FR-4) printed circuit board (PCB). The vibration levels were imposed by a controlled deflection at the center of the board at its natural frequency. The electric continuity was monitored to determine the number of cycles to failure of each sample. Mode shape measurements with a scanning vibrometer were also conducted and correlated with finite element analysis (FEA) to ensure accurate calculation of strain within the critical solder balls at the corners of the component. The failed specimens were then cross-sectioned in order to determine failure modes. A comparison of SAC305 durability with SnPb36Ag2 solder is given, along with a set of lifetime measurements for two complementary assemblies: 68 I/O Leadless Chip Carrier (LCC68) and 324 I/O Plastic Ball Grid Array (PBGA324). For the tested harmonic vibration levels, SAC305 outperforms SnPb36Ag2. Furthermore, the effect of temperature on the mechanical durability of SAC305 appears to be minor. Failure analysis pointed out different failure modes on PCB and component side, along with pad cratering and copper trace failures. FEA calculations allows the determination of the SAC305 fatigue curve to estimate the high cycle fatigue (HCF) behavior of SAC305 solder under harmonic vibrations. The random vibrations durability of SAC305 solder was assessed using the same test assembly (FBGA1152) which was subjected to three different levels of Power Spectral Density (PSD) at 20°C. The random vibrations tests were conducted within a frequency band ranging from 500 Hz to 900 Hz around the natural frequency. The chosen PSD levels applied were 0.04, 0.10 and 0.20 g2/Hz. Using power-law fitting, the results give a first estimation of the durability of SAC305 solder joints subjected to random vibrations.

International audience ; Vibration-induced solder joint fatigue is a main reliability concern for aerospace and military industries whose electronic equipment used in the field is required to remain functional under harsh loadings. Due to the RoHS directive which eventually will prevent lead from being utilized in electronic systems, there is a need for a better understanding of lead-free mechanical behavior under vibration conditions. This study reports the durability of Sn3.0Ag0.5Cu (SAC305) solder joints subjected to harmonic solicitations at three specific temperatures (-55°C, 20°C and 105°C) and random vibrations at ambient temperature (20°C). A test assembly was designed and consisted in a single daisy-chained 1152 I/O ball grid array (FBGA1152) package assembled on a flame retardant (FR-4) printed circuit board (PCB). The vibration levels were imposed by a controlled deflection at the center of the board at its natural frequency. The electric continuity was monitored to determine the number of cycles to failure of each sample. Mode shape measurements with a scanning vibrometer were also conducted and correlated with finite element analysis (FEA) to ensure accurate calculation of strain within the critical solder balls at the corners of the component. The failed specimens were then cross-sectioned in order to determine failure modes. A comparison of SAC305 durability with SnPb36Ag2 solder is given, along with a set of lifetime measurements for two complementary assemblies: 68 I/O Leadless Chip Carrier (LCC68) and 324 I/O Plastic Ball Grid Array (PBGA324). For the tested harmonic vibration levels, SAC305 outperforms SnPb36Ag2. Furthermore, the effect of temperature on the mechanical durability of SAC305 appears to be minor. Failure analysis pointed out different failure modes on PCB and component side, along with pad cratering and copper trace failures. FEA calculations allows the determination of the SAC305 fatigue curve to estimate the high cycle fatigue (HCF) behavior of SAC305 solder under harmonic ...

Abstract: Mobile gait analysis using wearable inertial measurement units (IMUs) provides valuable insights for the assessment of movement impairments in different neurological and musculoskeletal diseases, for example Parkinson's disease (PD). The increase in data volume due to arising long-term monitoring requires valid, robust and efficient analysis pipelines. In many studies an upstream detection of gait is therefore applied. However, current methods do not provide a robust way to successfully reject non-gait signals. Therefore, we developed a novel algorithm for the detection of gait from continuous inertial data of sensors worn at the feet. The algorithm is focused not only on a high sensitivity but also a high specificity for gait. Sliding windows of IMU signals recorded from the feet of PD patients were processed in the frequency domain. Gait was detected if the frequency spectrum contained specific patterns of harmonic frequencies. The approach was trained and evaluated on 150 clinical measurements containing standardized gait and cyclic movement tests. The detection reached a sensitivity of 0.98 and a specificity of 0.96 for the best sensor configuration (angular rate around the medio-lateral axis). On an independent validation data set including 203 unsupervised, semi-standardized gait tests, the algorithm achieved a sensitivity of 0.97. Our algorithm for the detection of gait from continuous IMU signals works reliably and showed promising results for the application in the context of free-living and non-standardized monitoring scenarios. This work was supported by the Mobilise-D project that has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No. 820820. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation program and the European Federation of Pharmaceutical Industries and Associations (EFPIA). Content in this publication reflects the authors' view and neither IMI nor the European Union, EFPIA, or ...

Recently, a supramolecular model was developed for predicting striated skeletal muscle intensity profiles obtained by label-free second harmonic generation (SHG) microscopy. This model allows for a quantitative determination of the length of the thick filament antiparallel range or M-band (M), and results in M ¼ 0.12 μm for single-band intensity profiles when fixing the A-band length (A) to A ¼ 1.6 μm, a value originating from electron microscopy (EM) observations. Using simulations and experimental data sets, we showed that the objective numerical aperture (NA) and the refractive index (RI) mismatch (Δn ¼ n2ω − nω) between the illumination wave (ω) and the second harmonic wave (2ω) severely affect the simulated sarcomere intensity profiles. Therefore, our recovered filament lengths did not match with those observed by EM. For an RI mismatch of Δn ¼ 0.02 and a moderate illumination NA of 0.8, analysis of single-band SHG intensity profiles with freely adjustable A- and M-band sizes yielded A ¼ 1.40 0.04 μm and M ¼ 0.07 0.05 μm for skeletal muscle. These lower than expected values were rationalized in terms of the myosin density distribution along the myosin thick filament axis. Our data provided new and practical insights for the application of the supramolecular model to study SHG intensity profiles in striated muscle. ; This research is part of the Interreg EMR IV-A project BioMiMedics (www.biomimedics.org) and is cofinanced by the European Union, local governments, research institutes and SMEs. Support by the BELSPO funded IAP-PAI network P7/05 on Functional Supramolecular Systems (FS2) is acknowledged. The Province of Limburg (Belgium) is acknowledged for financial support within the tUL IMPULS FASE II program, allowing for the upgrading of the laser source used in this work.

Introduction/purpose: This paper presents a numerical study of the forced dynamic behavior of a functionally graded beam subjected to a harmonically varying transversely concentrated moving force using a higher-order shear deformation theory. Methods: The governing equations are derived using Hamilton's principle. These equations are then transformed into the weak form using the Galerkin method. The problem is solved using the finite element method by developing a three-node finite element with four degrees of freedom per node. The Newmark beta method is chosen for the time integration and the Gauss method for the spatial integration. Results: The effects of several parameters were investigated, including the slenderness ratio, the material index, foundation stiffness, velocity and the frequency of the moving load. Good agreement was observed with the results obtained from the literature. Conclusion: This study illustrates the importance of using a higher order theory in the case of short beams and clearly shows the change in the behavior of the FGM beam as a function of different parameters.

This paper explores the application and non-application of final /n/ deletion in Ghayeni Persian. In this dialect, final /n/ deletion is a productive phonological process whose application in different domains and environments is affected by several opaque counterbleeding and counterfeeding interactions as well as bleeding. This research presents new empirical data about these aspects which could be of general theoretical interest. It is also an attempt to make a contribution to current debate in phonological opacity. In so doing, it adopts Harmonic Serialism (HS) to accommodate counterbleeding opacity. It offers an analysis to survive a pitfall challenging HS in handling counterbleeding opacity in derived words. With regard to counterfeeding opacity, it adopts Parallel Optimality Theory (POT) using Local Constraint Conjunction (LCC). It discusses how POT and HS in particular could treat opaque interactions in Ghayeni dialect. In addition, this paper argues that a candidate which undergoes the same process twice in the same step could also be included in HS's gradualness condition.