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1

Adaptive GFRP rotor blades and additive manufacturing of the molding tools

Ost Lucas, Seidlitz Holger, Kuke Felix, Yellur Manoja Rao, Krenz Jonas, Ulke-Winter Lars

Zarządzanie Przedsiębiorstwem

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2021

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Vol. 24, nr 1-2

15--18

EN

Small wind turbines are mostly designed for strong and medium wind regions, which are scaled by manufacturers based on similarity rules. However, the inland region represents a low wind region where the commercially available blades are not profitable. In this work, a rotor blade was designed for these wind conditions and further performance improvement of the turbine was generated by self-adaptive adjustment of the blades to the variable wind loads. This adaptation is achieved by a ply structure that exhibits bending-torsion coupling. The tooling for the production of the GFRP rotor blades was manufactured using a large-format 3D extrusion printer.

2

Adaptive iterative deblending of simultaneous source seismic data based on sparse inversion

Wei Yajie, Cao Jingjie, Huang Xiaogang, Chen Xue, Cai Zhicheng

Acta Geophysica

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2021

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Vol. 69, no. 2

497--507

EN

Deblending of simultaneous-source seismic data is becoming more popular in seismic exploration since it can greatly improve the efciency of seismic acquisition and reduce acquisition cost. At present, the deblending methods of simultaneous-source seismic data are mainly divided into two types: fltering method and sparse inversion method. Compared with the fltering method, the sparse inversion method has higher precision, but the selection of its parameter value mainly depends on experience, which is not suitable for large-scale seismic data processing. In this paper, an adaptive iterative deblending method based on sparse inversion is proposed. By improving the original iterative solution method of regularization inversion model, the efective signal and blending noise are weakened simultaneously in the iterative process, so that the energy intensity of blending noise is consistent with that of the efective signal in each iterative, so as to ensure the consistency of the regular parameter calculation method of each iteration. By analyzing the distribution of coefcients in the curvelet domain of pseudo-deblending data and blending noise, it is concluded that the value of regular parameters is the maximum amplitude of residual pseudo-deblending data in the curvelet domain multiplied by a coefcient between 0 and 1. In the process of iterative deblending, the regularized parameters are obtained adaptively from the data itself. It not only ensures the accuracy of the calculation results, but also improves the calculation efciency, which is suitable for large-scale seismic data processing.

3

On real order passivity

Gallegos J. A., Duarte-Mermoud M. A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 3

445--454

EN

The aim of this paper is to show that a real order generalization of the dissipative concepts is a useful tool to determine the stability (in the Lyapunov and in the input-output sense) and to design control strategies not only for fractional order non-linear systems, but also for systems composed of integer and fractional order subsystems (mixed-order systems). In particular, the fractional control of integer order system (e.g. PI? control) can be formalized. The key point is that the gradations of dissipativeness, passivity and positive realness concepts are related among them. Passivating systems is used as a strategy to stabilize them, which is studied in the non-adaptive as well as in the adaptive case.

4

An adaptive synthesis calibration method for time- interleaved sampling systems

Pan H., Tian S., Ye P.

Metrology and Measurement Systems

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2010

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Vol. 17, nr 3

405-414

EN

In a parallel time-interleaved data sampling system, timing and amplitude mismatches of this structure degrade the performance of the whole ADC system. In this paper, an adaptive blind synthesis calibration algorithm is proposed, which could estimate the timing, gain and offset errors simultaneously, and calibrate automatically. With no need of an extra calibration signal and redesign, it could efficiently and dynamically track the changes of mismatches due to aging or temperature variation. A fractional delay filter is developed to adjust the timing mismatch, which simplifies the design and decreases the cost. Computer simulations are also included to demonstrate the effectiveness of the proposed method.

5

Adaptive Coded Continuous-Phase Modulations for Frequency-Division Multiuser Systems

Perotti A., Remlein P., Benedetto S.

Advances in Electronics and Telecommunications

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2010

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Vol. 1, no. 1

50--58

EN

In this paper we study adaptive coded modulations for wireless channels. Nonlinearity due to the radio-frequency power amplifier is considered and continuous-phase modulations (CPM) are adopted in order to make the nonlinearity effects negligible. The structure and properties of CPM are reviewed in a semi-tutorial fashion and coded modulation schemes are proposed. Moreover, frequency-division multiplexing (FDM) multiuser systems employing coded CPM are considered. Modulation-coding schemes achieving increasing spectral efficiencies in a multiuser scenario with tight intercarrier frequency spacing are designed and their performance in terms of spectral efficiency and error rate is assessed.

6

Temperature Distribution Measuring System

Bazylevych O., Ivakhiv O., Velgan R.

Pomiary Automatyka Kontrola

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2007

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R. 53, nr 9 bis

583--585

EN

The pyrometer moving along the stove axis can be used for the surface temperature measurement of the circulating cement stove. By the temperature distribution along the rotor stove measuring, all possible temperature values in space and time can be described using a simple two-dimensional random temperature field model. Thus, the measuring signal is redundant, and it is possible to use the known compression techniques in order to reduce the requirements to the measuring information processing rate. The paper presents expressions estimating the parameters of this kind of adaptive system.

PL

Pomiar rozkładu temperatury powierzchni pieca do wypalania cementu zrealizowano za pomocą pirometru poruszającego się wzdłóż osi pieca. Jako dane pomiarowe do modelu matematychnego rozkładu temperatury w czasie i przestrzeni wykorzystano dwuwymiarowe pole losowe temperatury zarejestrowane pirometrem. W związku z faktem, że sygnał pomiarowy zawiera więcej niż potrzeba informacji, należy wykorzystać znane metody kompresji danych, umożliwiające spełnienie wymagań dotyczących szybkości przetwarzania danych pomiarowych. W pracy podano odnośne wzory służące do obliczeń w takim adaptacyjnym systemie pomiarowym.

7

An efficient object tracking method based on adaptive nonparametric approach

Li L., Feng Z.

Opto-Electronics Review

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2005

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Vol. 13, No. 4

325-330

EN

In this paper, an efficient method for object tracking based on nonparametric approach is presented. The density we estimated is based on an adaptive kernel model, which is driven by the intensity difference between the target and the background. The background-weighted histogram for statistics of feature takes into account the relevance between the target and background. What is more, this approach extends the range that is needed for searching object. The target model is updated according to the change of the object and environment. Experimental results on real image sequences demonstrate its robust performance in visual tracking and require less iteration computations when compared to other method.

8

Loads on walls and inserts in a mass-flow silos

Ding S., Wójcik M., Jecmenica M., Silva de S. R.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2003

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Vol. 7, No 4

525-538

EN

A finite element analysis has been carried out to investigate flow patterns and loads on silos either with a ralatively steep hopper, or with a shallow hopper but in the presence of an insert. A Lagrangian-Eulerian approach was first adopted to simulate the material flow pattern, with the precondition that mass flow was obtained. It was then attempted to predict the loads exerted by granular materials on the walls of such silos. The load on the insert was also simulated. Techniques such as the adoption of adaptive meshes and filleting along sharp corners were applied in the analysis to overcome the difficulties usually encountered with large deformations in the FEM and the mathematic singularity presented by the abruptness of geometry. Filleting proved to be necessary to bring down the pressure peak at the transition level. The insert took over a significant part of the loads. Comparison with the classic theories have confirmed that the loads predicted on the wall agree quite well with the theoretical results in the silo's cylinder section, but that differences exist in the hopper section; the difference is greater when the hopper is shallower. It has also shown the limitations of predicting flow patterns of granular materials with the traditional elastic-plastic model; a more advanced model is needed.

9

Real-time forecasting of water levels using adaptive neuro- fuzzy systems

Gautam D. K., Holz K. P., Meyer Z.

Archives of Hydro-Engineering and Environmental Mechanics

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2001

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Vol. 48, nr 4

3-21

EN

Real-time forecasting of high water levels at the mouth section of the Odra river is important for the safety conditions of shipping, shipyard works, river banks pro-tection, flood control and overall management of aquatic environment in the area. While numerical hydrodynamic models offer one possible solution, such models require forecasting of all boundary conditions and forcing data, calibration of model parameters and are often too complex and time consuming. These models are not very suitable for real-time forecasting where fast solutions are required to provide ad-equate lead time. Simpler approaches offered by artificial intelligence methods such as artificial neural networks and fuzzy rule-based systems are thus becoming more attractive and promising alternatives. These methods provide a fast, sufficiently good and low-cost solution. In this paper, an application of Adaptive-Network-Based Fuzzy Inference System (ANFIS) is presented for real-time forecasting of water levels at Police on the mouth section of the Odra river.