Wyniki wyszukiwania - BazTech

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Three-dimensional underwater path planning based on modified potential field algorithm in time-varying current

Wang Shasha, Feng Guilin, Wang Dan, Tuo Yulong

Polish Maritime Research

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2023

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nr 1

33--42

EN

The article addresses the three-dimensional (3D) underwater path planning problem of an autonomous underwater vehicle (AUV) in a time-varying current. A modified artificial potential field algorithm combining the velocity vector synthesis method is proposed to search for the optimal path. The modified potential field (MPF) algorithm is designed to dynamically plan the non-collision path. Meanwhile, this modified method is also proved to be an effective solution to the goals not reachable with obstacles nearby (GNRON), U-shaped trap, and rotation unreachable problems. To offset the influence of time-varying current, the velocity synthesis approach is designed to adjust the AUV movement direction. Besides, considering path planning in the complex underwater environment, the multi-beam forward-looking sonar (FLS) model is used. Finally, simulation studies substantiate that the designed algorithm can implement the AUV path planning effectively and successfully in a 3D underwater environment.

2

Deep-segmentation of plantar pressure images incorporating fully convolutional neural networks

Wang Dan, Li Zairan, Dey Nilanjan, Ashour Amira S., Moraru Luminita, Simon Sherratt R., Shi Fuqian

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 1

546--558

EN

Comfort shoe-last design relies on the key points of last curvature. Traditional plantar pressure image segmentation methods are limited to their local and global minimization issues. In this work, an improved fully convolutional networks (FCN) employing SegNet (SegNet+FCN 8 s) is proposed. The algorithm design and operation are performed using the visual geometry group (VGG). The method has high efficiency for the segmentation in positive indices of global accuracy (0.8105), average accuracy (0.8015), and negative indices of average cross-ratio (0.6110) and boundary F1 index (0.6200). The research has potential applications in improving the comfort of shoes.

3

Plantar pressure image fusion for comfort fusion in diabetes mellitus using an improved fuzzy hidden Markov model

Li Zairan, Wang Dan, Dey Nilanjan, Ashour Amira S., Sherratt R. Simon, Shi Fuqian

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

742--752

EN

Diabetes mellitus is a clinical syndrome caused by the interaction of genetic and environmental factors. The change of plantar pressure in diabetic patients is one of the important reasons for the occurrence of diabetic foot. The abnormal increase of plantar pressure is a predictor of the common occurrence of foot ulcers. The feature extraction of plantar pressure distribution will be beneficial to the design and manufacture of diabetic shoes that will be beneficial for early protection of diabetes mellitus patients. In this research, texture-based features of the angular second moment (ASM), moment of inertia (MI), inverse difference monument (IDM), and entropy (E) have been selected and fused by using the updown algorithm. The fused features are normalized to predict comfort plantar pressure imaging dataset using an improved fuzzy hidden Markov model (FHMM). In FHMM, type-I fuzzy set is proposed and fuzzy Baum–Welch algorithm is also applied to estimate the next features. The results are discussed, and by comparing with other back–forward algorithms and different fusion operations in FHMM. Improved HMMs with up–down fusion using type-I fuzzy definition performs high effectiveness in prediction comfort plantar pressure distribution in an image dataset with an accuracy of 82.2% and the research will be applied to the shoe-last personalized customization in the industry.