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1

A Rattle Signal Denoising and Enhancing Method Based on Wavelet Packet Decomposition and Mathematical Morphology Filter for Vehicle

Liang Linyuan, Chen Shuming, Li Peiran

Archives of Acoustics

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2022

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Vol. 47, No. 1

43--55

EN

Buzz, squeak and rattle (BSR) noise has become apparent in vehicles due to the significant reductions in engine noise and road noise. The BSR often occurs in driving condition with many interference signals. Thus, the automatic BSR detection remains a challenge for vehicle engineers. In this paper, a rattle signal denoising and enhancing method is proposed to extract the rattle components from in-vehicle background noise. The proposed method combines the advantages of wavelet packet decomposition and mathematical morphology filter. The critical frequency band and the information entropy are introduced to improve the wavelet packet threshold denoising method. A rattle component enhancing method based on multi-scale compound morphological filter is proposed, and the kurtosis values are introduced to determine the best parameters of the filter. To examine the feasibility of the proposed algorithm, synthetic brake caliper rattle signals with various SNR ratios are prepared to verify the algorithm. In the validation analysis, the proposed method can well remove the disturbance background noise in the signal and extract the rattle components with well SNR ratios. It is believed that the algorithm discussed in this paper can be further applied to facilitate the detection of the vehicle rattle noise in industry.

2

Grid Fault Diagnosis Based on Information Entropy and Multi-source Information Fusion

Zeng Xin, Xiong Xingzhong, Luo Zhongqiang

International Journal of Electronics and Telecommunications

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2021

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Vol. 67, No. 2

143--148

EN

In order to solve the problem of misjudgment caused by the traditional power grid fault diagnosis methods, a new fusion diagnosis method is proposed based on the theory of multi-source information fusion. In this method, the fault degree of the power element is deduced by using the Bayesian network. Then, the time-domain singular spectrum entropy, frequency-domain power spectrum entropy and wavelet packet energy spectrum entropy of the electrical signals of each circuit after the failure are extracted, and these three characteristic quantities are taken as the fault support degree of the power components. Finally, the four fault degrees are normalized and classified as four evidence bodies in the D-S evidence theory for multi-feature fusion, which reduces the uncertainty brought by a single feature body. Simulation results show that the proposed method can obtain more reliable diagnosis results compared with the traditional methods.

3

An active exploration method for data efficient reinforcement learning

Zhao Dongfang, Liu Jiafeng, Wu Rui, Cheng Dansong, Tang Xianglong

International Journal of Applied Mathematics and Computer Science

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2019

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Vol. 29, no. 2

351--362

EN

Reinforcement learning (RL) constitutes an effective method of controlling dynamic systems without prior knowledge. One of the most important and difficult problems in RL is the improvement of data efficiency. Probabilistic inference for learning control (PILCO) is a state-of-the-art data-efficient framework that uses a Gaussian process to model dynamic systems. However, it only focuses on optimizing cumulative rewards and does not consider the accuracy of a dynamic model, which is an important factor for controller learning. To further improve the data efficiency of PILCO, we propose its active exploration version (AEPILCO) that utilizes information entropy to describe samples. In the policy evaluation stage, we incorporate an information entropy criterion into long-term sample prediction. Through the informative policy evaluation function, our algorithm obtains informative policy parameters in the policy improvement stage. Using the policy parameters in the actual execution produces an informative sample set; this is helpful in learning an accurate dynamic model. Thus, the AEPILCOalgorithm improves data efficiency by learning an accurate dynamic model by actively selecting informative samples based on the information entropy criterion. We demonstrate the validity and efficiency of the proposed algorithm for several challenging controller problems involving a cart pole, a pendubot, a double pendulum, and a cart double pendulum. The AEPILCO algorithm can learn a controller using fewer trials compared to PILCO. This is verified through theoretical analysis and experimental results.

4

Improved dolphin swarm optimization algorithm based on information entropy

Li Y., Wang X.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 4

679--685

EN

In order to overcome the shortcomings of the dolphin algorithm, which is prone to falling into local optimum and premature conver-gence, an improved dolphin swarm algorithm, based on the standard dolphin algorithm, was proposed. As a measure of uncertainty, information entropy was used to measure the search stage in the dolphin swarm algorithm. Adaptive step size parameters and dynamic balance factors were introduced to correlate the search step size with the number of iterations and fitness, and to perform adaptive adjustment of the algorithm. Simulation experiments show that, comparing with the basic algorithm and other algorithms, the improved dolphin swarm algorithm is feasible and effective.

5

A method of comparative studies on checkup sets to evaluate the technical condition of tractors

Staszak Ż., Grześ Z., Rybacki P.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 3

450--454

EN

In this paper the authors propose an original method of the numerical evaluation of checkup sets for the technical condition of an agricultural tractor. Information entropy required in diagnostic tests for a specific checkup set was used as the evaluation criterion. A formal description is given for the technical condition diagnostics of a tractor in its operation period, which is characterised by a high rate of average damage. The structural model was constructed using information entropy. This model accumulates the number of checkups, probability of specific damage types and assigns them a common numerical measure. The conducted logic analysis of the proposed method and the results obtained in experiments on its practical applicability in service stations indicate that the method adequately describes this area of machine operation and thus may be a measure of information effectiveness for checkup sets determining the machine technical condition.

PL

W pracy zaproponowano oryginalną metodę liczbowej oceny zbiorów sprawdzeń stanu technicznego ciągnika rolniczego. Jako kryterium oceny wykorzystano entropię informacyjną, konieczną do uzyskania w badaniach diagnostycznych dla odpowiedniego zbioru sprawdzeń. Wykonano formalny opis procesu oceny stanu technicznego ciągnika w systemie eksploatacji, który charakteryzuje duży udział uszkodzeń awaryjnych. Do budowy modelu strukturalnego wykorzystano entropię informacyjną, Model ten kumuluje w sobie liczbę sprawdzeń, prawdopodobieństwo wystąpienia określonych uszkodzeń i nadaje im wspólną miarę liczbową. Przeprowadzona logiczna analiza proponowanej metody oraz wyniki uzyskane w badaniach z jej praktycznego zastosowania w zakładach serwisowych wskazują, że opisuje adekwatnie ten obszar eksploatacji maszyn i może być miarą efektywności informacyjnej zbiorów sprawdzeń stanu technicznego maszyn.

6

Carpooling Scheme Selection for Taxi Carpooling Passengers: a Multi-Objective Model and Optimisation Algorithm

Xiao Q., He R.-C.

Archives of Transport

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2017

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Vol. 42, iss. 2

85--92

EN

Carpooling has been long deemed a promising approach to better utilizing existing transportation infrastructure, the carpooling system can alleviate the problems of traffic congestion and environmental pollution effectively in big cities. However, algorithmic and technical barriers inhibit the development of taxi carpooling, and it is still not the preferred mode of commute. In order to improve carpooling efficiency in urban, a taxi carpooling scheme based on multi-objective model and optimisation algorithm is presented. In this paper, urban traffic road network nodes were constructed from the perspective of passenger carpooling. A multi-objective taxi carpooling scheme selection model was built based on an analysis of the main influences of carpooling schemes on passengers. This model aimed to minimise get-on-and-get-off distance, carpooling waiting time and arriving at the destination. Furthermore, a two-phase algorithm was used to solve this model. A rapid searching algorithm for feasible routes was established, and the weight vector was assigned by introducing information entropy to obtain satisfying routes. The algorithm is applied to the urban road, the Simulation experimental result indicates that the optimisation method presented in this study is effective in taxi carpooling passengers.

7

Using data reconciliation to improve the reliability of the energy evaluation of a gas-and-steam CHP unit

Szega M.

Journal of Power Technologies

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2015

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Vol. 95, spec.

91--99

EN

The development of distributed control systems and automatic storage of measuring data permits a better supervision of processes of energy conversion. In most cases the running energy evaluation of these processes based on the raw measuring data. The paper deals with the application of the data reconciliation method in order to improve the reliability of thermal measurements of a gas-and-steam CHP unit. Identification of the thermal system of an example gas-and-steam CHP unit and its measurements system have been carried out. A mathematical model of investigated CHP unit equipped with a gas turbine, heat recovery steam generator, extraction-condensing steam turbine and heat exchangers has been presented. In the case of energy evaluation mainly balance equations of mass and energy are taken into account. From the data reconciliation method point of view a surplus of measurements information in the distributed control system of analyzed CHP unit has been found. As a conditional equations in the data reconciliation algorithm, mass and energy balances formulated so far within the model of gas-and-steam CHP unit have been applied. Data reconciliation calculations for analyzed gas-and-steam CHP unit have been carried out. The statistical test of control of the assumed uncertainty of raw measurements using variance-covariance matrix of measurements corrections has been applied. For global assessment of results of data reconciliation calculations a relative information entropy has been applied. The relative entropy – Kullback-Leibler divergence, which is a non-symmetric measure of the difference between two probability distributions, has been used. The necessity of data reconciliation method to increase reliability and uncertainty of measurements data in calculations of parameters characterizing the process of energy conversion in gas-and-steam CHP unit has been demonstrated. Usefulness of application of an information entropy for global assessment of reliability improvement of measurements after data reconciliation calculations has been presented.

8

A Granular Computing Approach to Symbolic Value Partitioning

Wen L.-Y., Min F.

Fundamenta Informaticae

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2015

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Vol. 142, nr 1-4

337--371

EN

Symbolic value partitioning is a knowledge reduction technique in the field of data mining. In this paper, we propose a granular computing approach for the partitioning task that includes granule construction and granule selection algorithms. The granule construction algorithm takes advantage of local information associated with each attribute. A binary attribute value taxonomy tree is built to merge these attribute values in a bottom-up manner using information-loss heuristics. The use of a balancing technique enables us to control different nodes in the same level to have approximately the same size. The granule selection algorithm uses global information about all of the attributes in the decision system. Hence, nodes across the taxonomy forest of all attributes are selected and expanded using information-gain heuristics. We present a series of experimental results that demonstrate the effectiveness of the proposed approach in terms of reducing the data size and improving the resulting classification accuracy.

9

A Multifaceted Analysis of Probabilistic Three-way Decisions

Deng X., Yao Y.

Fundamenta Informaticae

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2014

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Vol. 132, nr 3

291--313

EN

In situations where available information or evidence is incomplete or uncertain, probabilistic two-way decisions/classifications with a single threshold on probabilities for making either an acceptance or a rejection decision may be inappropriate. With the introduction of a third non-commitment option, probabilistic three-way decisions use a pair of thresholds and provide an effective and practical decision-making strategy. This paper presents a multifaceted analysis of probabilistic three-way decisions. By identifying an inadequacy of two-way decisions with respect to controlling the levels of various decision errors, we examine the motivations and advantages of three-way decisions. We present a general framework for computing the required thresholds of a three-way decision model as an optimization problem. We investigate two special cases, one is a decision-theoretic rough set model and the other is an information-theoretic rough set model. Finally, we propose a heuristic algorithm for finding the required thresholds.

10

Technical solutions for bio-measurements

Konieczny L., Markiewicz M., Piwowar P., Roterman I.

Bio-Algorithms and Med-Systems

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2012

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Vol. 8, no. 4

339--349

EN

Biological processes are controlled automatically. Registration of signals and measuring their relative strength is hence a key problem. Receptors may be relatively simple or complex. The complexity is the direct response to ambiguity of signals. If there is however a common feature of diverse signals a construction of generic receptor mechanism is usually observed. Combinatorial technique is commonly used in biological systems to decrease the complexity in reception of highly ambiguous signals.

11

Calculation of thermal power of a heat recovery steam generator with reliability increase of the measurements by applying the data reconciliation

Szega M.

Rynek Energii

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2011

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nr 2

157-162

EN

Heat recovery steam generator (waste-heat boiler) constitutes a connection between open thermal cycle of a gas turbine and steam cycle in a gas-and-steam power or CHP unit. Connection of the both thermal cycles cause, that for measured fluxes of steam and flue gases and theirs thermodynamic parameters there is a possibility of calculation of thermal power of heat recovery steam generator basing on calculation of increase of steam enthalpy or decrease of the flue gases enthalpy. Because of inevitability errors of measurements, the thermal power calculated according to both ways is not equal. In order to remove incompatibility of both calculated thermal powers, the data reconciliation algorithm has been applied. Identification of an example gas-and-steam CHP unit and his measurements system have been carried out. From the data reconciliation method point of view a surplus of measurements information in the distributed control system has been found. Selected mass and energy balances for gas-and-steam unit, constituting at the same time a conditional equations in the data reconciliation algorithm has been formulated. Calculations of thermal power of heat recovery steam generator and its standard uncertainty in case of lack of surplus measurements information, and in case with data reconciliation have been carried out. For assessment of results of data reconciliation calculations an information entropy has been applied. The necessity of data reconciliation method to increase reliability and uncertainty of measurements data in calculations of parameters characterizing the thermal process has been demonstrated. Usefulness of use of an information entropy for global assessment of reliability improvement of measurements after data reconciliation calculations has been presented.

PL

W siłowni lub elektrociepłowni gazowo-parowej kocioł odzyskowy stanowi połączenie otwartego obiegu turbiny gazowej i obiegu parowego. Połączenie obydwu obiegów w kotle odzyskowym powoduje, że dla pomiarowo dostępnych strumieni czynników przepływających przez kocioł oraz ich parametrów termicznych istnieje możliwość obliczenia jego mocy cieplnej za pomocą przyrostu entalpii czynników od strony wodno-parowej kotła oraz spadku entalpii przepływających przez kocioł spalin. Z uwagi na nieuniknione błędy pomiarów obliczone według obu sposobów moce cieplne kotła nie będą sobie równe. W celu eliminacji niezgodności obliczonych mocy cieplnych zastosowano metodę uwiarygodnienia pomiarów za pomocą rachunku wyrównawczego. Przeprowadzono identyfikację układu cieplnego oraz systemu pomiarów eksploatacyjnych dla wybranej elektrociepłowni gazowo-parowej. Stwierdzono występowanie nadmiaru informacji pomiarowej dla kotła odzyskowego nie tylko w przypadku jego bilansu energii, lecz także w obiegach gazowym i parowym. Sformułowano wybrane bilanse substancji i energii dla układu cieplnego rozważanej elektrociepłowni gazowo-parowej, stanowiące jednocześnie układ równań warunków w procedurze uwiarygodnienia pomiarów. Przeprowadzono obliczenia mocy cieplnej kotła odzyskowego i jej niepewności standardowej dla przypadków występowania minimalnej informacji pomiarowej oraz z zastosowaniem metody uwiarygodnienia pomiarów. Do oceny wyników obliczeń uwiarygodnienia pomiarów zastosowano metodę z wykorzystaniem entropii informacji. Wykazano konieczność stosowania metod rachunku wyrównawczego dla uwiarygodnienia pomiarów służących do obliczeń osiągalnych parametrów procesu cieplnego. Pokazano przydatność wykorzystania entropii informacji do całościowej oceny poprawy wiarygodności pomiarów po zastosowaniu metody rachunku wyrównawczego.

12

Application of the entropy information for the optimization of an additional measurements location in thermal systems

Szega M.

Archives of Thermodynamics

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2011

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Vol. 32, no. 3

215-229

EN

For the optimal location of an additional surplus measurements in the design of redundant measurements system, from data reconciliation point of view, of thermal processes, an information entropy has been applied. The relative entropy - Kullback-Leibler divergence, has been used. As a criterion of the optimal location of an additional surplus measurements in a system of measurements data, the minimum of the entropy information of reconciled measurements data has been assumed. Hence, the objective function in the described optimization task is maximum of the relative entropy - Kullback-Leibler divergence concerning sets of raw and reconciled measurements data. Simulation calculation with application of data reconciliation algorithm and Monte Carlo method concerning the influence of installation of the additional surplus measurements on decrease of entropy information of measurements after data validation have been carried out. The example calculations concerned the cross high-pressure heat regeneration system with cascade flow of condensate installed in 153 MW power unit equipped with cooler of steam are presented. Calculations for all variants of configurations of an additional surplus measurements in the analyzed thermal system have been done. Usefulness of the proposed Kullback-Leibler divergence as a objective function has been demonstrated.

13

Adaptive Ant Colony Optimization Algorithm Based on Information Entropy: Foundation and Application

Li Y., Li W.

Fundamenta Informaticae

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2007

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Vol. 77, nr 3

229-242

EN

In order to solve the premature convergence problem of the basic Ant Colony Optimization algorithm, a promising modification based on the information entropy is proposed. The main idea is to evaluate stability of the current space of represented solutions using information entropy, which is then applied to turning of the algorithm's parameters. The path selection and evolutional strategy are controlled by the information entropy self-adaptively. Simulation study and performance comparison with other Ant Colony Optimization algorithms and other meta-heuristics on Traveling Salesman Problem show that the improved algorithm, with high efficiency and robustness, appears self -adaptive and can converge at the global optimum with a high probability. The work proposes a more general approach to evolutionary-adaptive algorithms related to the population's entropy and has significance in theory and practice for solving the combinatorial optimization problems.

14

Zastosowanie entropii informacji do oceny sieci monitoringu jakości wód podziemnych

Kucharek M., Treichel W.

Ochrona Środowiska

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2006

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R. 28, nr 3

45-49

PL

W pracy przedstawiono metodę oceny sieci monitoringu jakości wód podziemnych pod kątem ilości informacji, jaką sieć monitoringu jest w stanie dostarczyć do systemu kontroli. Traktując sieć monitoringu jako sygnałowy system komunikacyjny, mający zdolność przekazu informacji hydrologicznej, można do tego systemu zastosować kryteria oceny wykorzystujące pojęcia z teorii informacji Shannona. Podstawowym kryterium jest wartość marginalnej entropii informacyjnej, obliczona dla każdej lokalizacji punktu pomiarowego, która stanowi narzędzie pomiaru ilości informacji zawartych w danych. Na podstawie wartości tego kryterium zaproponowano warianty zmniejszenia liczby punktów pomiarowych w analizowanej sieci monitoringu wód podziemnych zbiornika odpadów poflotacyjnych "Żelazny Most", gromadzącego odpady powstałe w procesie przeróbki rudy miedzi. Zaprezentowano wyniki badań dotyczące pomiarów właściwości fizyczno-chemicznych wody ze 132 piezometrów przedpola wschodniego zbiornika. Badania zostały oparte o kampanię pomiarową wykonaną w 2000 r. W ocenie wzięto pod uwagę zagęszczenie sieci monitoringu wokół składowiska, przy czym analizowany obszar podzielono na trzy strefy, w zależności od odległości od zapory. Przeanalizowano sposób rozmieszczenia punktów pomiarowych, uwzględniając wartość entropii w poszczególnych strefach. Porównano entropię informacyjną na różnych etapach zmniejszania sieci kontrolnej. Wykazano, że prawidłowa ocena funkcjonalności sieci monitoringu wód podziemnych w rejonie składowiska odpadów poflotacyjnych "Żelazny Most" może w przyszłości pomóc w podejmowaniu decyzji związanych z ograniczeniem jego wpływu na środowisko.

EN

With this method, the groundwater quality monitoring network is assessed in terms of the amount of information that can be supplied to the control system. If we assume that the monitoring network is a signal communication system capable of providing hydrological information, we can use the assessment criteria dealt with in the Shannon information theory. The fundamental criterion derived from this theory is the value of marginal information entropy calculated for each location of the sampling point. These values are assumed to be the measure of the amount of information included in the data. Furthermore, some variants are proposed of how to reduce the number of measuring points in the existing monitoring network. Our study involved the groundwater monitoring network serving a reservoir (called "Żelazny Most") which receives post-flotation contaminants originating in the course of copper ore treatment. The reservoir has been classified as one of the world's largest industrial waste disposal site. The paper shows the results of physicochemical analysis of the groundwater from 132 piezometers located in the E forefield area. Samples were taken in the year 2000. The assessment of the network also included its density. The area under analysis was divided into three zones according to the distance from the barrage. The combination of spacing between the control points was analyzed in terms of the entropy value for each zone. The information entropy values were compared at each stage of reducing the number of the measuring points. A reliable assessment of the performance of the groundwater quality monitoring network will be of considerable help to environmentalists whose decisions about abating the environmental impact due to such industrial waste disposal sites must be based on dependable information.

15

Informational representation of fundamental phenomena in the digital electro-optical imaging devices

Jakubik P., Pospišil J.

Optica Applicata

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2003

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Vol. 33, nr 4

635-648

EN

This article contains basic theoretical results of mathematical interpretations of some fundamental phenomena in the modern digital electronic (electro-optical) imaging devices (systems) with pixel photodetection structure mainly from the standpoint of the mean mutual information. For that purpose, the systems in question are approximated by a suitable linear and isoplanatic signal transfer model of a 2D stationary and ergodic continuous stochastic distribution of the object scene-light intensity which is limited in size by the input field of view. The mathematical modelling of the phenomena presented is based on utilizing the continuous linear signal transfer theory and the extended modern communication and information theory for the spectral domain of spatial frequencies, in particular. The equations put forward are acceptable for an analysis and optimal synthesis of digital electronic imaging systems fitting the signal transfer model proposed. Conventionally, these systems give better information efficiency and image quality in comparison with the older analog imaging systems.

16

Informational entropy in simulation of one-dimensional random fields

Opoka Sz., Walukiewicz H.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2002

|

Vol. 6, No 3

379-385

EN

The entropy H of a continuous distribution with probability density function f* is defined as a function of the number of nodes (n) in a one-dimensional scalar random field. For the second order theory this entropy is expressed by the determinants of the covariance matrices and simulated for several types of correlation functions. In the numerical example the propagation of the entropy for the static response of linear elastic, randomly loaded beam has been considered. Two unexpected results have been observed: - function H(n) is entirely different for differentiable (m.s.) and non-differentiable fields, with the same parameters in the correlation functions, - in some cases, the greater randomness at the input (measured by the entropy) does not lead to the greater randomness at the output.