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1.
Front Mol Biosci ; 9: 1009099, 2022.
Article in English | MEDLINE | ID: mdl-36504714

ABSTRACT

The accurate prediction of potential associations between microRNAs (miRNAs) and small molecule (SM) drugs can enhance our knowledge of how SM cures endogenous miRNA-related diseases. Given that traditional methods for predicting SM-miRNA associations are time-consuming and arduous, a number of computational models have been proposed to anticipate the potential SM-miRNA associations. However, several of these strategies failed to eliminate noise from the known SM-miRNA association information or failed to prioritize the most significant known SM-miRNA associations. Therefore, we proposed a model of Graph Convolutional Network with Layer Attention mechanism for SM-MiRNA Association prediction (GCNLASMMA). Firstly, we obtained the new SM-miRNA associations by matrix decomposition. The new SM-miRNA associations, as well as the integrated SM similarity and miRNA similarity were subsequently incorporated into a heterogeneous network. Finally, a graph convolutional network with an attention mechanism was used to compute the reconstructed SM-miRNA association matrix. Furthermore, four types of cross validations and two types of case studies were performed to assess the performance of GCNLASMMA. In cross validation, global Leave-One-Out Cross Validation (LOOCV), miRNA-fixed LOOCV, SM-fixed LOOCV and 5-fold cross-validation achieved excellent performance. Numerous hypothesized associations in case studies were confirmed by experimental literatures. All of these results confirmed that GCNLASMMA is a trustworthy association inference method.

2.
Sensors (Basel) ; 22(19)2022 Sep 30.
Article in English | MEDLINE | ID: mdl-36236542

ABSTRACT

In recent years, much research has been conducted on time series based human activity recognition (HAR) using wearable sensors. Most existing work for HAR is based on the manual labeling. However, the complete time serial signals not only contain different types of activities, but also include many transition and atypical ones. Thus, effectively filtering out these activities has become a significant problem. In this paper, a novel machine learning based segmentation scheme with a multi-probability threshold is proposed for HAR. Threshold segmentation (TS) and slope-area (SA) approaches are employed according to the characteristics of small fluctuation of static activity signals and typical peaks and troughs of periodic-like ones. In addition, a multi-label weighted probability (MLWP) model is proposed to estimate the probability of each activity. The HAR error can be significantly decreased, as the proposed model can solve the problem that the fixed window usually contains multiple kinds of activities, while the unknown activities can be accurately rejected to reduce their impacts. Compared with other existing schemes, computer simulation reveals that the proposed model maintains high performance using the UCI and PAMAP2 datasets. The average HAR accuracies are able to reach 97.71% and 95.93%, respectively.


Subject(s)
Human Activities , Wearable Electronic Devices , Computer Simulation , Humans , Machine Learning , Probability
3.
Sensors (Basel) ; 21(23)2021 Nov 23.
Article in English | MEDLINE | ID: mdl-34883795

ABSTRACT

With the rapid development of the computer and sensor field, inertial sensor data have been widely used in human activity recognition. At present, most relevant studies divide human activities into basic actions and transitional actions, in which basic actions are classified by unified features, while transitional actions usually use context information to determine the category. For the existing single method that cannot well realize human activity recognition, this paper proposes a human activity classification and recognition model based on smartphone inertial sensor data. The model fully considers the feature differences of different properties of actions, uses a fixed sliding window to segment the human activity data of inertial sensors with different attributes and, finally, extracts the features and recognizes them on different classifiers. The experimental results show that dynamic and transitional actions could obtain the best recognition performance on support vector machines, while static actions could obtain better classification effects on ensemble classifiers; as for feature selection, the frequency-domain feature used in dynamic action had a high recognition rate, up to 99.35%. When time-domain features were used for static and transitional actions, higher recognition rates were obtained, 98.40% and 91.98%, respectively.


Subject(s)
Algorithms , Support Vector Machine , Human Activities , Humans , Smartphone
4.
Sensors (Basel) ; 20(18)2020 Sep 09.
Article in English | MEDLINE | ID: mdl-32916963

ABSTRACT

Aiming at the influence of uneven illumination on fabric feature extraction and the limitations of traditional frequency-based visual saliency algorithms, we propose a fabric defect detection method based on the combination of illumination correction and visual salient features-(1) Construct a multi-scale side window box (MS-BOX) filter to extract the illumination component of the image, then use the constructed two-dimensional gamma correction function to perform illumination correction on the image in the global angle, and finally enhance the local contrast of the image in the local angle; (2) Use the L0 gradient minimization method to remove the background texture of fabric images and highlight the defects; (3) Represent the fabric image as a quaternion image, where each pixel in the image is represented by a quaternion consisting of color, intensity and edge characteristics. The two-dimensional fractional Fourier transform (2D-FRFT) is used to obtain the saliency map of the quaternion image. Experiments show that our method has a higher overall recall rate for defect detection of star-patterned, box-patterned, and dot-patterned fabrics, and the overall recall-precision effect is better than other existing methods.

5.
Sensors (Basel) ; 20(18)2020 Sep 11.
Article in English | MEDLINE | ID: mdl-32932774

ABSTRACT

In contemporary research on human action recognition, most methods separately consider the movement features of each joint. However, they ignore that human action is a result of integrally cooperative movement of each joint. Regarding the problem, this paper proposes an action feature representation, called Motion Collaborative Spatio-Temporal Vector (MCSTV) and Motion Spatio-Temporal Map (MSTM). MCSTV comprehensively considers the integral and cooperative between the motion joints. MCSTV weighted accumulates limbs' motion vector to form a new vector to account for the movement features of human action. To describe the action more comprehensively and accurately, we extract key motion energy by key information extraction based on inter-frame energy fluctuation, project the energy to three orthogonal axes and stitch them in temporal series to construct the MSTM. To combine the advantages of MSTM and MCSTV, we propose Multi-Target Subspace Learning (MTSL). MTSL projects MSTM and MCSTV into a common subspace and makes them complement each other. The results on MSR-Action3D and UTD-MHAD show that our method has higher recognition accuracy than most existing human action recognition algorithms.


Subject(s)
Algorithms , Joints , Pattern Recognition, Automated , Human Activities , Humans , Motion , Movement
6.
ScientificWorldJournal ; 2014: 593065, 2014.
Article in English | MEDLINE | ID: mdl-25161396

ABSTRACT

This paper deals with the implementation of Steiner point of fuzzy set. Some definitions and properties of Steiner point are investigated and extended to fuzzy set. This paper focuses on establishing efficient methods to compute Steiner point of fuzzy set. Two strategies of computing Steiner point of fuzzy set are proposed. One is called linear combination of Steiner points computed by a series of crisp α-cut sets of the fuzzy set. The other is an approximate method, which is trying to find the optimal α-cut set approaching the fuzzy set. Stability analysis of Steiner point of fuzzy set is also studied. Some experiments on image processing are given, in which the two methods are applied for implementing Steiner point of fuzzy image, and both strategies show their own advantages in computing Steiner point of fuzzy set.


Subject(s)
Algorithms , Fuzzy Logic , Pattern Recognition, Automated
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(1): 50-3, 2007 Jan.
Article in Chinese | MEDLINE | ID: mdl-17390647

ABSTRACT

Infrared spectra of semen celosiae and semen celosiae cristatae were obtained directly, quickly and accurately by Fourier transform infrared spectroscopy (FTIR) with OMNI sampler. Continuous wavelet transform was used to extrude local region of infrared spectra of semen celosiae and its confusable varieties. The difference of infrared spectra between semen celosiae and semen celosiae cristatae was extruded greatly. Accurate identification rate was improved greatly. Morlet wavelet, which can detect singular values of signal effectively, was selected as the mother wavelet. One-dimensional continuous wavelet transform was implemented for the infrared spectra of semen celosiae and its confusable varieties. The difference between semen celosiae and semen celosiae cristatae was observed at all scales in the wavelet domain. An optimal scale, at which the difference between semen celosiae and semen celosiae cristatae was the most obvious, was selected to identify semen celosiae and semen celosiae cristatae. The results show that it is effective to apply continuous wavelet transform on the basis of FTIR to identify the traditional Chinese medicinal materials, which are the same genus but different species.


Subject(s)
Celosia/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Humans
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