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1

Design Low Complexity SCMA Codebook Using Arnold’s Cat Map

Mohamed Sura S., Abdullah Hikmat N.

Journal of Telecommunications and Information Technology

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2022

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nr 4

13--20

EN

In 5G wireless communications, sparse code multiple access (SCMA) – a multi-dimensional codebook based on a specific category of the non-orthogonal multiple access (NOMA) technique - enables many users to share non-orthogonal resource components with a low level of detection complexity. The multi-dimensional SCMA (MD-SCMA) codebook design presented in this study is based on the constellation rotation and interleaving method. Initially, a subset of the lattice Z 2 is used to form the mother constellation’s initial dimension. The first dimension is then rotated to produce other dimensions. Additionally, interleaving is employed for even dimensions to enhance fading channel performance. Arnold’s chaotic cat map is proposed as the interleaving method to reduce computational complexity. Performance of the SCMA codebook based on interleaving is evaluated by comparing it with selected codebooks for SCMA multiplexing. The metrics used for performance evaluation purposes include bit error rate (BER), peak to average power ratio (PAPR), and minimum Euclidean distance (MED), as well as complexity. The results demonstrate that the suggested codebook with chaotic interleaving offers performance that is equivalent to that of the conventional codebook based on interleaving. It is characterized by lower MED and higher BER compared to computer-generated and 16-star QAM codebook design approaches, but its complexity is lower than that of the conventional codebook based on interleaving.

2

Online parameter identification of SPMSM based on improved artificial bee colony algorithm

Wu Chunli, Jiang Shuai, Bian Chunyuan

Archives of Electrical Engineering

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2021

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Vol. 70, nr 4

777--790

EN

The artificial bee colony (ABC) intelligence algorithm is widely applied to solve multi-variable function optimization problems. In order to accurately identify the parameters of the surface-mounted permanent magnet synchronous motor (SPMSM), this paper proposes an improved ABC optimization method based on vector control to solve the multi-parameter identification problem of the PMSM. Because of the shortcomings of the existing parameter identification algorithms, such as high computational complexity and data saturation, the ABC algorithm is applied for the multi-parameter identification of the PMSM for the first time. In order to further improve the search speed of the ABC algorithm and avoid falling into the local optimum, Euclidean distance is introduced into the ABC algorithm to search more efficiently in the feasible region. Applying the improved algorithm to multi-parameter identification of the PMSM, this method only needs to sample the stator current and voltage signals of the motor. Combined with the fitness function, the online identification of the PMSM can be achieved. The simulation and experimental results show that the ABC algorithm can quickly identify the motor stator resistance, inductance and flux linkage. In addition, the ABC algorithm improved by Euclidean distance has faster convergence speed and smaller steady-state error for the identification results of stator resistance, inductance and flux linkage.

3

Comparison of methods for correcting outliers in ECG-based biometric identification

Jun Su, Szmajda Miroslaw, Khoma Volodymyr, Khoma Yuriy, Sabodashko Dmytro, Kochan Orest, Wang Jinfei

Metrology and Measurement Systems

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2020

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Vol. 27, nr 3

387--398

EN

The aim of this paper is to compare the efficiency of various outlier correction methods for ECG signal processing in biometric applications. The main idea is to correct anomalies in various segments of ECG waveform rather than skipping a corrupted ECG heartbeat in order to achieve better statistics. Experiments were performed using a self-collected Lviv Biometric Dataset. This database contains over 1400 records for 95 unique persons. The baseline identification accuracy without any correction is around 86%. After applying the outlier correction the results were improved up to 98% for autoencoder based algorithms and up to 97.1% for sliding Euclidean window. Adding outlier correction stage in the biometric identification process results in increased processing time (up to 20%), however, it is not critical in the most use-cases.

4

Determination of the Optimal Threshold Value and Number of Keypoints in Scale Invariant Feature Transform-based Copy-Move Forgery Detection

Isnanto R. Rizal, Zahra Ajub Ajulian, Santoso Imam, Lubis Muhammad Salman

International Journal of Electronics and Telecommunications

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2020

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Vol. 66, No. 3

561--569

EN

The copy-move forgery detection (CMFD) begins with the preprocessing until the image is ready to process. Then, the image features are extracted using a feature-transform-based extraction called the scale-invariant feature transform (SIFT). The last step is features matching using Generalized 2 Nearest-Neighbor (G2NN) method with threshold values variation. The problem is what is the optimal threshold value and number of keypoints so that copy-move detection has the highest accuracy. The optimal threshold value and number of keypoints had determined so that the detection n has the highest accuracy. The research was carried out on images without noise and with Gaussian noise.

5

The evaluation of text string matching algorithms as an aid to image search

Ochelska-Mierzejewska J.

Journal of Applied Computer Science

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2018

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Vol. 26, nr 1

33--62

EN

The main goal of this paper is to analyse intelligent text string matching methods (like fuzzy sets and relations) and evaluate their usefulness for image search. The present study examines the ability of different algorithms to handle multi-word and multi-sentence queries. Eight different similarity measures (N-gram, Levenshtein distance, Jaro coefficient, Dice coefficient, Overlap coefficient, Euclidean distance, Cosine similarity and Jaccard similarity) are employed to analyse the algorithms in terms of time complexity and accuracy of results. The outcomes are used to develop a hierarchy of methods, illustrating their usefulness to image search. The search response time increases significantly in the case of data sets containing several thousand images. The findings indicate that the analysed algorithms do not fulfil the response-time requirements of professional applications. Due to its limitations, the proposed system should be considered only as an illustration of a novel solution with further development perspectives. The use of Polish as the language of experiments affects the accuracy of measures. This limitation seems to be easy to overcome in the case of languages with simpler grammar rules (e.g. English).

6

Evaluating organizational antifragility via fuzzy logic : the case of an Iranian company producing banknotes and security paper

Ghasemi A., Alizadeh M.

Operations Research and Decisions

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2017

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Vol. 27, No. 2

21--43

EN

The concept of antifragility has received much attention from researchers in recent years. Contrary to fragile systems which fail when exposed to stressors, antifragile systems prosper and improve in response to unpredictability, volatility, randomness, chaos and disturbance. The implications of antifragility goes beyond resilience or robustness. A resilient system resists stress and remains the same; while an antifragile system improves. Taleb argues that antifragility is required for dealing with events that he called black swans or X-events, which are scarce, unpredictable, and extreme events. Such events come as a surprise and have major consequences. The concept of antifragility was developed by Taleb in a socioeconomic context, not in industrial production. However, the authors think that this concept may have its greatest practical utilization when applied to industrial environments. Thus, they focused on this concept in the article aiming to investigate the level of antifragility in an organization. In order to perform this, the authors used a case study based on an Iranian manufacturer of banknotes and security paper (TAKAB). Firstly, a questionnaire was designed based on 7 criteria related to antifragility using the five-point Likert scale and a triangular fuzzy number for each linguistic term is defined. In the next phase, the weight of each component was obtained using the entropy technique. In the final stage, the Euclidean distance between the aggregated fuzzy antifragility index (FAI) and each linguistic term used during this case study was calculated. Finally, based on these results, the level of the organization’s antifragility was assessed as satisfactorily antifragile, based on the minimum Euclidean distance.

7

Yarn-Dyed Fabric Defect Detection Based On Autocorrelation Function And GLCM

Zhu D., Pan R., Gao W., Zhang J.

Autex Research Journal

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2015

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Vol. 15, no. 3

226--232

EN

In this study, a new detection algorithm for yarn-dyed fabric defect based on autocorrelation function and grey level co-occurrence matrix (GLCM) is put forward. First, autocorrelation function is used to determine the pattern period of yarn-dyed fabric and according to this, the size of detection window can be obtained. Second, GLCMs are calculated with the specified parameters to characterise the original image. Third, Euclidean distances of GLCMs between being detected images and template image, which is selected from the defect-free fabric, are computed and then the threshold value is given to realise the defect detection. Experimental results show that the algorithm proposed in this study can achieve accurate detection of common defects of yarn-dyed fabric, such as the wrong weft, weft crackiness, stretched warp, oil stain and holes.

8

Algorytm porównania histogramów wielomodalnych opóźnień komunikacyjnych w transmisji bezprzewodowej

Krupanek B., Bogacz R.

Przegląd Elektrotechniczny

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2014

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R. 90, nr 11

32--34

PL

Do opisu parametrów transmisji komunikatów, zwłaszcza w sieciach z losowym dostępem do nośnika, bardzo często stosuje się histogram. W praktyce często zachodzi konieczność porównania dwóch lub więcej histogramów – mówi się wtedy o identyfikacji parametrów rozkładu. W referacie przedstawiono metodę porównywania histogramów w kontekście transmisji bezprzewodowej.

EN

To describe the wireless transmission parameters, in particular in networks with random access to the medium, very often are used histograms. In practice, it is often necessary to compare two or more histograms – this is the identification process of parameters of the distribution. The paper presents various methods of comparing histograms in the context of wireless transmission.

9

Zastosowanie modeli dokładnych sieci do detekcji i lokalizacji wycieków

Tomasik P.

Problemy Eksploatacji

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2011

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nr 2

223-230

PL

W referacie opisano metodę wykorzystującą dokładne modele sieci wodociągowej do detekcji i lokalizacji wycieków. Metoda ta bazuje na prostej mierze podobieństwa pomiędzy rzeczywistymi i modelowymi danymi o przepływach w sieci wodociągowej.

EN

The paper describes a method of using accurate models of the water supply system for detecting and locating leaks. This method is based on a simple measure of similarity between real and simulated data on water flows in the water supply.

10

Gabriel graph of geomagnetic Sq variations

Sridharan M., Ramasamy A.M.S.

Acta Geophysica

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2010

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Vol. 58, no. 6

973-987

EN

This paper describes the pattern of geomagnetic solar quiet day, Sq, variations recorded at the Indian geomagnetic observatories. The extent to which the high and low latitude ionosphere is interlinked electromagnetically during periods of quiet geomagnetic conditions is a point of debate. The concept of Gabriel graph is applied to derive the boundaries for the variations of horizontal, vertical, and declination components of the earth’s magnetic field during geomagnetically quiet periods. Data of the six Indian geomagnetic observatories (Alibag, Hyderabad, Nagpur, Pondicherry, Visakapatnam, and Trivandrum) are considered for this analysis. This graph theoretical model is complementary to the classical data analysis techniques. Analytical method and the results of the analysis are presented in the paper.

11

Koncepcja systemu do diagnostyki złozonego procesu przemysłowego

Tomasik P.

Pomiary Automatyka Kontrola

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2005

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R. 51, nr 9 bis

327--329

PL

W referacie przedstawiona została metoda wyznaczania podobieństwa pomiędzy poszczególnymi realizacjami procesu dla wielu parametrów procesowych. Istota, tej metody jest wyszukiwanie podobnych cykli procesowych do zadanego (na postawie bazy cykli archiwalnych) w celu wspomagania obsługi procesu w podejmowaniu decyzji.

EN

The paper deals with a method of calculation of a similarity between different control sequences of many process parameters. This new method uses a polynomial approximation and Euclidean distance. Intention of this method is to accelerate the process of acquiring of rules for the decision support system.