Clustering of fMRI Data Using Affinity Propagation

Biometric identification is getting more and more popular as the demand of security increases. Iris is a promising biometric because of its stability and uniqueness. In this paper, a novel iris analysis method is proposed by using Affinity Propagation (AP) Algorithm. AP algorithm is a new clustering method by transforming the input matrix of similarity between pairs of data points. The proposed method is evaluated using the Chinese Academy of Sciences-Institute of Automation (CASIA) iris image database, the similarity between two irises is measured by their negative Hamming Distance. Experiments indicate that the algorithm has excellent solution in iris analysis, when AP algorithm is used as preprocess in an iris identification system, it can greatly decrease the time complexity of iris recognition.

Portfolio optimization refers to the reasonable allocation of assets to achieve the investment objectives. At present, the investment environment depression was due to sluggish economic conditions. For investors, they expect to find a balance between return and risk in a complex investment environment. In order to solve this problem, this paper proposes a portfolio optimization algorithm named Portfolio Optimization based on Affinity propagation and Genetic algorithm, as also called POGA, which based on affinity propagation and genetic algorithm. Firstly, the affinity propagation algorithm is used to construct a candidate set of portfolio based on the correlation analysis of the stock time series. Secondly, using the Sharpe-ratio as the Optimization objective function, the genetic algorithm is used to solve an optimal portfolio strategy with higher-return and lower-risk. Finally, the experimental result of real-world stock data show that a portfolio with higher return and lower risk will be selected.

In this paper, we propose a feature combination, also known as feature fusion, for improving performance in content-based gastric image retrieval (CBGIR). This study provides a CBGIR system that retrieves images by combining ResNet-18 and ResNet-50 information and finally, the Euclidean distance metric is evaluated for similarity measurement. The proposed approach is also compared to different deep learning techniques such as AlexNet, VGGs (VGG-16 & VGG-19), GoogleNet, SqueezeNet, DarkNet-19 models. The proposed method was examined on the KVASIR database with 4000 images and S different classes. We get the optimum results as average precision of 95.44% and average recall of 19.09 on a scale of 20 using the proposed deep learning model and Euclidean distance metric.

BackgroundReducing TB surveillance incurs significant costs, as effective control and societal impact minimization rely on robust, ongoing surveillance systems that integrate and analyze comprehensive data for prompt action. Our study supports integrating artificial intelligence (LSI) into TB and other notifiable disease monitoring frameworks to improve trackingFigure 1Binary Matrix of 125 Terms: Presence vs. Absence of Root Keywords Retrieved from the Patient ElectronicRecord for the LSI Automatic Retrieval System.Binary Matrix of 125 Terms: Presence vs. Absence of Root Keywords Retrieved from the Patient Electronic Record for the LSI Automatic Retrieval System.MethodsIn 2024, we developed a novel application within Datamart A.R.G.U.S.—Assistant for Recovery and Guarding of Urgent and Epidemiological Sentinels—a cloud-based platform hosted on AWS and developed by our team. This application integrates with hospital systems (MV) and laboratory systems (MATRIX and GAL) to enhance the surveillance of healthcare-associated infections (HAI) and notifiable diseases. Data from both hospital and outpatient care are encoded into a binary matrix of 125 terms (root keywords) extracted from patient electronic records. This matrix is then processed using Singular Value Decomposition (SVD) within an LSI-based information retrieval system (Fig. 1). In our model, each patient is represented as a point in a 125-dimensional hyperdimensional space. When projected into three-dimensional space, this framework allows for effective clustering and classification of notifiable Diseases (Fig. 2), specifically TB (Fig. 3).Figure 2:3D Visualization of High-Dimensional Data: Comparing Mandatory Notifiable Diseases versus Non-Notifiable Diseases. Both patient types are well separated in the space, enabling automatic clustering and classification.3D Visualization of High-Dimensional Data: Comparing Mandatory Notifiable Diseases versus Non-Notifiable Diseases. Both patient types are well separated in the space, enabling automatic clustering and classification.ResultsThe LSI-based matrix was constructed using data from January 2023 to February 2024, encompassing a sample of 17,895 cases (lines) across 125 presence versus absence terms, with each case classified as either a notifiable or non-notifiable disease. The 125-dimensional matrix was reduced to 28 factors using SVD. The sensitivity and specificity of the Euclidean distance were better than those of cosine similarity when automatically identifying TB cases in 1,970 independent queries (Fig. 4).Figure 3:3D Visualization of High-Dimensional Data: Comparing Tuberculosis versus Other Mandatory Notifiable Diseases versus Non-Notifiable Diseases. The three types of patients are well separated in the space, enabling automatic clustering and classification.3D Visualization of High-Dimensional Data: Comparing Tuberculosis versus Other Mandatory Notifiable Diseases versus Non-Notifiable Diseases. The three types of patients are well separated in the space, enabling automatic clustering and classification.ConclusionArtificial Intelligence (LSI), significantly enhances the surveillance of TB and other notifiable diseases by enabling real-time, automated case identification up to one day prior (D-1). This advancement allows surveillance personnel to complete their tasks more efficiently, thereby preventing outbreaks and reducing the risk of unforeseen fatalities.Figure 4:Performance Comparison of Cosine vs. Euclidean Distance Metrics in Automatically Identifying TB Cases Using LSI: Euclidean Distance Demonstrates Superior Accuracy and Has Been Integrated into Datamart A.R.G.U.S. for Real-Time Identification of TB and Other Notifiable Diseases as of the Previous Workday (D-1).Performance Comparison of Cosine vs. Euclidean Distance Metrics in Automatically Identifying TB Cases Using LSI: Euclidean Distance Demonstrates Superior Accuracy and Has Been Integrated into Datamart A.R.G.U.S. for Real-Time Identification of TB and Other Notifiable Diseases as of the Previous Workday (D-1).DisclosuresAll Authors: No reported disclosures

Scientific mapping has now become an important subject in the scientometrics field. Journal clustering can provide insights into both the internal relations among journals and the evolution trend of studies. In this paper, we apply the affinity propagation (AP) algorithm to do scientific journal clustering. The AP algorithm identifies clusters by detecting their representative points through message passing within the data points. Compared with other clustering algorithms, it can provide representatives for each cluster and does not need to pre-specify the number of clusters. Because the input of the AP algorithm is the similarity matrix among data points, it can be applied to various forms of data sets with different similarity metrics. In this paper, we extract the similarity matrices from the journal data sets in both cross citation view and text view and use the AP algorithm to cluster the journals. Through empirical analysis, we conclude that these two clustering results by the two single views are highly complementary. Therefore, we further combine text information with cross citation information by using the simple average scheme and apply the AP algorithm to conduct multi-view clustering. The multi-view clustering strategy aims at obtaining refined clusters by integrating information from multiple views. With text view and citation view integrated, experiments on the Web of Science journal data set verify that the AP algorithm obtains better clustering results as expected.

The optimization of an assembly line layout can be modeled as a facility layout problem. Since an accurate representation of the real-world distances is essential for the validity of the optimization results, this paper compares the accuracy of the approximation of the real-world distances by the commonly used rectilinear and Euclidean distance metrics. Further, the influence of the size and aspect ratio of the machines on the approximation accuracy and the influence of the distance metrics on the solver runtime is studied. The results show the Euclidean distance metric being more accurate but extending computation time.

Blind source separation (BSS) is commonly used in functional magnetic resonance imaging (fMRI) data analysis. Recently, BSS models based on restricted Boltzmann machine (RBM), one of the building blocks of deep learning models, have been shown to improve brain network identification compared to conventional single matrix factorization models such as independent component analysis (ICA). These models, however, trained RBM on fMRI volumes, and are hence challenged by model complexity and limited training set. In this article, we propose to apply RBM to fMRI time courses instead of volumes for BSS. The proposed method not only interprets fMRI time courses explicitly to take advantages of deep learning models in latent feature learning but also substantially reduces model complexity and increases the scale of training set to improve training efficiency. Our experimental results based on Human Connectome Project (HCP) datasets demonstrated the superiority of the proposed method over ICA and the one that applied RBM to fMRI volumes in identifying task-related components, resulted in more accurate and specific representations of task-related activations. Moreover, our method separated out components representing intermixed effects between task events, which could reflect inherent interactions among functionally connected brain regions. Our study demonstrates the value of RBM in mining complex structures embedded in large-scale fMRI data and its potential as a building block for deeper models in fMRI data analysis.

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Fingerprint-based identification is one of the most well-known and publicized biometrics for personal identification. Extracting features out of poor quality prints is the most challenging problem faced in this area. In this paper, the texture feature based approach for fingerprint recognition using Discrete Wavelet Transform (DWT) is developed to identify the low quality fingerprint from inked-printed images on paper. The fingerprint image from paper is very poor quality image and sometimes it is complex with fabric background. Firstly, a center point area of the fingerprint is detected and keeping the Core Point as center point, the image of size w x w is cropped. Gabor filtering is applied for fingerprint enhancement over the orientation image. Finally, the texture features are extracted by analyzing the fingerprint with Discrete Wavelet Transform (DWT) and Euclidean distance metric is used as similarity measure. The accuracy is improved up to 98.98%.

Content Based Image Retrieval (CBIR) is a process in which for a given query image similar images will be retrieved based on the image content similarity. Image content refers to its visual features, which are mathematical representations of a digital image. The image retrieval task primarily depends on image feature extraction and similarity measurement between the feature vectors. The performance of CBIR process not only decided by the optimum features extracted from the image but also on the proper choice of the similarity/dissimilarity measures (distance metrics). As the image features broadly diversified in terms of color, texture and shape based, using the same distance metric may not work well for all of these features. In this paper, first we presented overview of geometric and statistical distance metrics used in CBIR along with the comparative analysis of these measures on color and texture features. Color features extracted by computing color histograms in HSV space and texture features by wavelet decompositions. Geometrical distances such as Manhattan, Chebyshev, Euclidean, statistical distance metrics such as Cosine Similarity, Chi-square, KullbackLeibler, Jeffrey and cumulative statistical distance metrics of Kolmogorov-Smirnov, Cramer von Mises and Earthmover's distances were analyzed for feature similarity. We gave certain conclusions on the performance of all these distance metrics in terms of Mean Average Precision (MAP) and Recall rates with color and texture features respectively.

Function magnetic resonance imaging (fMRI) data are typically contaminated by noise introduced by head motion, physiological noise, and thermal noise. To mitigate noise artifact in fMRI data, a variety of denoising methods have been developed by removing noise factors derived from the whole time series of fMRI data and therefore are not applicable to real-time fMRI data analysis. In the present study, we develop a generally applicable, deep learning based fMRI denoising method to generate noise-free realistic individual fMRI volumes (time points). Particularly, we develop a fully data-driven 3D convolutional encapsulated Long Short-Term Memory (3DConv-LSTM) approach to generate noise-free fMRI volumes regularized by an adversarial network that makes the generated fMRI volumes more realistic by fooling a critic network. The 3DConv-LSTM model also integrates a gate-controlled self-attention model to memorize short-term dependency and historical information within a memory pool. We have evaluated our method based on both task and resting state fMRI data. Both qualitative and quantitative results have demonstrated that the proposed method outperformed state-of-the-art alternative deep learning methods.

The last two decades have seen a surge in the interest in research based on Functional Magnetic Resonance Imaging (fMRI) data. Decoding of cognitive states based on fMRI activation profiles has become a very active topic in this area. fMRI data is very high dimensional and noisy. However, there is a dearth of datasets to work on. Sharing of learning by analyzing datasets drawn across multiple subjects in an experiment can help in increasing the amount of data we have for analysis. Decoding of cognitive states using classifiers trained across multiple subjects is a challenging task because of differences in anatomy and cognition. Selecting features to analyze from the dataset is a key step in the analysis of fMRI data. In this paper we apply PCA, ICA and five non-linear dimensionality reduction techniques to the fMRI data. The aim of this work is to analyze which technique can provide the best feature selection to capture the commonality across multiple subjects. The reduced datasets are then used to train classifiers to solve a multiple-subject decoding problem.KeywordsFeature SelectionIndependent Component AnalysisCognitive StateCanonical Correlation AnalysisFeature Selection MethodThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.