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Diagnosis of inter-turn short circuit fault in IPMSMs based on the combined use of greedy tracking and random forest

Wang Jianping, Ma Jian, Meng Dean, Zhao Xuan, Zhang Kai, Liu Qiquan, Xu Kejie

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148943

EN

Inter-turn short circuit (ITSC) is a frequent fault of interior permanent magnet synchronous motors (IPMSM). If ITSC faults are not promptly monitored, it may result in secondary faults or even cause extensive damage to the entire motor. To enhance the reliability of IPMSMs, this paper introduces a fault diagnosis method specifically designed for identifying ITSC faults in IPMSMs. The sparse coefficients of phase current and torque are solved by clustering shrinkage stage orthogonal matching tracking (CcStOMP) in the greedy tracking algorithm.The CcStOMP algorithm can extract multiple target atoms at one time, which greatly improves the iterative efficiency. The multiple features are utilized as input parameters for constructing the random forest classifier. The constructed random forest model is used to diagnose ITSC faults with the results showing that the random forest model has a diagnostic accuracy of 98.61% using all features, and the diagnostic accuracy of selecting three of the most important features is still as high as 97.91%. The random forest classification model has excellent robustness that maintains high classification accuracy despite the reduction of feature vectors, which is a great advantage compared to other classification algorithms. The combination of greedy tracing and the random forest is not only a fast diagnostic model but also a model with good generalisation and anti-interference capability. This non-invasive method is applicable to monitoring and detecting failures in industrial PMSMs.

2

Temperature and Humidity Data Evaluation of Tight Sportswear During Motion Based on Intelligent Modeling

Cheng Pengpeng, Wang Jianping, Zeng Xianyi, Bruniaux Pascal, Chen Daoling

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

1--8

EN

A neural network structure of Long Short Term Memory (LSTM) is proposed which could be used to predict the temperaturę and humidity of other key parts from the temperature and humidity data of some parts of the human body when wearing tight sportswear, so as to realize the temperature and humidity data prediction of all key points of the human body. The temperaturę and humidity of different people wearing tights were collected by DHT sensors. The experimental results show that the LSTM neural network structure proposed has higher prediction accuracy than other algorithms, and the model evaluates the feasibility of temperature and humidity data of tights in a state of motion, which facilitates the study of dynamic thermal and humid comfort and reduces the time cost of analyzing the temperature and humidity distribution and changing the law during human movement. It will effectively promote the study of temperature and humidity changes when people wear sports tights, provide theoretical reference for the study of human skin temperature in the field of sports medicine, and provide practical guidance for the application of human skin temperature changes in sports clothing production, diagnosis and prevention of sports injuries.

3

Intelligent Prediction Model of the Thermal and Moisture Comfort of the Skin-Tight Garment

Cheng Pengpeng, Wang Jianping, Zeng Xianyi, Bruniaux Pascal, Chen Daoling

Fibres & Textiles in Eastern Europe

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2022

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Vol. 30, no. 1 (151)

50--58

EN

In order to improve the efficiency and accuracy of predicting the thermal and moisture comfort of skin-tight clothing (also called skin-tight underwear), principal component analysis (PCA) is used to reduce the dimensions of related variables and eliminate the multicollinearity relationship among variables. Then, the optimized variables are used as the input parameters of the coupled intelligent model of the genetic algorithm (GA) and back propagation (BP) neural network, and the thermal and moisture comfort of different tights (tight tops and tight trousers) under different sports conditions is analysed. At the same time, in order to verify the superiority of the genetic algorithm and BP neural network intelligent model, the prediction results of GA-BP, PCA-BP and BP are compared with this model. The results show that principal component analysis (PCA) improves the accuracy and adaptability of the GA-BP neural network in predicting thermal and humidity comfort. The forecasting effect of the PCA-GA-BP neural network is obviously better than that of the GA-BP, PCA-BP, BP model, which can accurately predict the thermal and moisture comfort of tight-fitting sportswear. The model has better forecasting accuracy and a simpler structure.

4

Effects of Breast Support and Gait Speed on Three-Dimensional Breast Displacement for Women with Small Breasts

Chen Xiaona, Sun Guangwu, Wang Jianping, Li Yanmei, Xie Hong

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 2 (146)

87--94

EN

This paper investigated three-dimensional breast displacement under different breast suport conditions and gait speeds for women with small breasts. The breast coordinates of fifteen female participants with small breasts (sizes ranging from A to C) were recorded during treadmill walking and running tests under two different sports bra conditions and a no bra condition. The results showed that although vertical breast displacement was always the greatest in each condition, mediolateral breast displacement was significantly greater than anteroposterior breast displacement. Mediolateral breast displacement was not effectively reduced in the two sports bra conditions compared to the no bra condition. It is recommended that sports bra designed for women with small breasts should aim to limit mediolateral breast displacement instead of anteroposterior breast displacement, on the premise of controlling vertical breast displacement. The findings also suggest that the effectiveness of sports bras at reducing side-to-side breast movement requires further optimisation.

PL

W pracy zbadano trójwymiarowe przemieszczenie piersi przy różnych warunkach podtrzymywania piersi i szybkości chodu u kobiet z małymi piersiami. Współrzędne piersi piętnastu uczestniczek z małymi piersiami (rozmiary od A do C) rejestrowano podczas testów chodu na bieżni i biegania w stanikach sportowych i bez. Wyniki pokazały, że chociaż pionowe przemieszczenie piersi było zawsze największe w każdym stanie, środkowo-boczne przemieszczenie piersi było znacznie większe, niż przemieszczenie piersi przednio-tylne. Stwierdzono, że biustonosz sportowy nie zmniejszył skutecznie przemieszczenia biustu w bok w porównaniu ze stanem bez stanika. Zaleca się, aby stanik sportowy przeznaczony dla kobiet z małym biustem miał na celu ograniczenie środkowo-bocznego przemieszczenia piersi zamiast przesunięcia piersi w przód i tył, z założeniem kontrolowania pionowego przemieszczenia piersi. Odkrycia sugerują również, że skuteczność staników sportowych w ograniczaniu ruchów piersi na boki wymaga dalszej optymalizacji.

5

Breast Pain and Sports Bra Usage Reported by Chinese Women: Why Sports Bra Education Programs are Needed in China

Chen Xiaona, Wang Jianping, Wang Yanzhen, Gho Sheridan A., Steele Julie R.

Fibres & Textiles in Eastern Europe

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2019

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Vol. 27, no. 4 (136)

17--22

EN

This study aimed to evaluate breast pain and sports bra usage reported by Chinese women and to analyse whether they were affected by age, education, occupation, income or breast size. Four hundred and four Chinese women completed a questionnaire to determine their breast pain and its frequency as well as sports bra usage. Although more than 60% of Chinese women experienced breast pain during exercise, only 40% of them had ever worn a sports bra. The high percentage of participants who experienced breast pain and low percentage of sports bra usage confirmed the need to educate Chinese women on sport bra fit, design and reasons for wearing sports bras. Age, bra size and income level should be considered when implementing these educational programs.

PL

Celem badania była ocena bólu piersi i użytkowania biustonosza sportowego oraz analiza wyników ze względu na wiek, wykształcenie, zawód, dochód i rozmiar piersi użytkowniczek. Czterysta cztery chińskie kobiety wypełniły kwestionariusz w celu określenia bólu piersi i jego częstotliwości, a także użycia biustonosza sportowego. Chociaż ponad 60% chińskich kobiet doświadczyło bólu podczas ćwiczeń, tylko 40% z nich nosiło stanik sportowy. Wysoki odsetek uczestniczek, które doświadczyły bólu piersi i niskiego odsetka użycia biustonosza sportowego, potwierdziły potrzebę edukowania chińskich kobiet na temat sportowego dopasowania biustonosza, projektowania i powodów noszenia sportowych biustonoszy. Przy realizacji tych programów edukacyjnych należy wziąć pod uwagę wiek, rozmiar biustonosza i poziom dochodów użytkowniczek.