In reinforcement learning, accurate estimation of the Q-value is crucial for acquiring an optimal policy. However, current successful Actor-Critic methods still suffer from underestimation bias. Additionally, there exists a significant estimation bias, regardless of the method used in the critic initialization phase.
View Article and Find Full Text PDFBackground: Treatment of acute stroke, before a distinction can be made between ischemic and hemorrhagic types, is challenging. Whether very early blood-pressure control in the ambulance improves outcomes among patients with undifferentiated acute stroke is uncertain.
Methods: We randomly assigned patients with suspected acute stroke that caused a motor deficit and with elevated systolic blood pressure (≥150 mm Hg), who were assessed in the ambulance within 2 hours after the onset of symptoms, to receive immediate treatment to lower the systolic blood pressure (target range, 130 to 140 mm Hg) (intervention group) or usual blood-pressure management (usual-care group).
IEEE Trans Pattern Anal Mach Intell
December 2024
In point cloud, some regions typically exist nodes from multiple categories, i.e., these regions have both homophilic and heterophilic nodes.
View Article and Find Full Text PDFBackground And Objectives: Acute stent thrombosis (AST) is not uncommon and even catastrophic during intracranial stenting angioplasty in patients with symptomatic high-grade intracranial atherosclerotic stenosis (ICAS). The purpose of this study was to investigate whether adjuvant intravenous tirofiban before stenting could reduce the risk of AST and periprocedural ischemic stroke in patients receiving stent angioplasty for symptomatic ICAS.
Methods: A prospective, multicenter, open-label, randomized clinical trial was conducted from September 9, 2020, to February 18, 2022, at 10 medical centers in China.
IEEE Trans Neural Netw Learn Syst
November 2023
In this article, a new unsupervised contrastive clustering (CC) model is introduced, namely, image CC with self-learning pairwise constraints (ICC-SPC). This model is designed to integrate pairwise constraints into the CC process, enhancing the latent representation learning and improving clustering results for image data. The incorporation of pairwise constraints helps reduce the impact of false negatives and false positives in contrastive learning, while maintaining robust cluster discrimination.
View Article and Find Full Text PDFGraph Convolutional Networks (GCNs) have shown remarkable performance in processing graph-structured data by leveraging neighborhood information for node representation learning. While most GCN models assume strong homophily within the networks they handle, some models can also handle heterophilous graphs. However, the selection of neighbors participating in the node representation learning process can significantly impact these models' performance.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
September 2023
Consensus clustering is to find a high quality and robust partition that is in agreement with multiple existing base clusterings. However, its computational cost is often very expensive and the quality of the final clustering is easily affected by uncertain consensus relations between clusters. In order to solve these problems, we develop a new k -type algorithm, called k -relations-based consensus clustering with double entropy-norm regularizers (KRCC-DE).
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
December 2023
Graph convolutional neural networks can effectively process geometric data and thus have been successfully used in point cloud data representation. However, existing graph-based methods usually adopt the K-nearest neighbor (KNN) algorithm to construct graphs, which may not be optimal for point cloud analysis tasks, owning to the solution of KNN is independent of network training. In this paper, we propose a novel graph structure learning convolutional neural network (GSLCN) for multiple point cloud analysis tasks.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
November 2024
Few-shot knowledge graph completion (FKGC), which aims to infer new triples for a relation using only a few reference triples of the relation, has attracted much attention in recent years. Most existing FKGC methods learn a transferable embedding space, where entity pairs belonging to the same relations are close to each other. In real-world knowledge graphs (KGs), however, some relations may involve multiple semantics, and their entity pairs are not always close due to having different meanings.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
May 2023
The bagging method has received much application and attention in recent years due to its good performance and simple framework. It has facilitated the advanced random forest method and accuracy-diversity ensemble theory. Bagging is an ensemble method based on simple random sampling (SRS) method with replacement.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
August 2023
For a classification task, we usually select an appropriate classifier via model selection. How to evaluate whether the chosen classifier is optimal? One can answer this question via Bayes error rate (BER). Unfortunately, estimating BER is a fundamental conundrum.
View Article and Find Full Text PDFPlant nitrogen (N) uptake preference is a key factor affecting plant nutrient acquisition, vegetation composition and ecosystem function. However, few studies have investigated the contribution of different N sources to plant N strategies, especially during the process of primary succession of a glacial retreat area. By measuring the natural abundance of N isotopes (δN) of dominant plants and soil, we estimated the relative contribution of different N forms (ammonium-NH, nitrate-NO and soluble organic N-DON) and absorption preferences of nine dominant plants of three stages (12, 40 and 120 years old) of the Hailuogou glacier retreat area.
View Article and Find Full Text PDFAs a leading graph clustering technique, spectral clustering is one of the most widely used clustering methods to capture complex clusters in data. Some additional prior information can help it to further reduce the difference between its clustering results and users' expectations. However, it is hard to get the prior information under unsupervised scene to guide the clustering process.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
April 2024
Graph neural networks (GNNs) have made great progress in graph-based semi-supervised learning (GSSL). However, most existing GNNs are confronted with the oversmoothing issue that limits their expressive ability. A key factor that leads to this problem is the excessive aggregation of information from other classes when updating the node representation.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
February 2023
The pure accuracy measure is used to eliminate random consistency from the accuracy measure. Biases to both majority and minority classes in the pure accuracy are lower than that in the accuracy measure. In this paper, we demonstrate that compared with the accuracy measure and F-measure, the pure accuracy measure is class distribution insensitive and discriminative for good classifiers.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
October 2023
We consider the problem of distinguishing direct causes from direct effects of a target variable of interest from multiple manipulated datasets with unknown manipulated variables and nonidentical data distributions. Recent studies have shown that datasets attained from manipulated experiments (i.e.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
December 2022
Multi-modal classification (MMC) aims to integrate the complementary information from different modalities to improve classification performance. Existing MMC methods can be grouped into two categories: traditional methods and deep learning-based methods. The traditional methods often implement fusion in a low-level original space.
View Article and Find Full Text PDFThis study builds a fully deconvolutional neural network (FDNN) and addresses the problem of single image super-resolution (SISR) by using the FDNN. Although SISR using deep neural networks has been a major research focus, the problem of reconstructing a high resolution (HR) image with an FDNN has received little attention. A few recent approaches toward SISR are to embed deconvolution operations into multilayer feedforward neural networks.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
September 2021
Semi-supervised clustering is one of important research topics in cluster analysis, which uses pre-given knowledge as constraints to improve the clustering performance. While clustering a data set, people often get prior constraints from different information sources, which may have different representations and contents, to guide clustering process. However, most of existing semi-supervised clustering algorithms are based on single-source constraints and rarely consider to integrate multi-source constraints to enhance the clustering quality.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
October 2018
In data mining, objects are often represented by a set of features, where each feature of an object has only one value. However, in reality, some features can take on multiple values, for instance, a person with several job titles, hobbies, and email addresses. These features can be referred to as set-valued features and are often treated with dummy features when using existing data mining algorithms to analyze data with set-valued features.
View Article and Find Full Text PDFMost proteins perform their biological functions while interacting as complexes. The detection of protein complexes is an important task not only for understanding the relationship between functions and structures of biological network, but also for predicting the function of unknown proteins. We present a new nodal metric by integrating its local topological information.
View Article and Find Full Text PDFTwo new three-dimensional isostructural lanthanide metal-organic frameworks (Ln(III)-MOFs), [LnL(HO)]·3HO·0.75DMF (1-Ln; Ln = Dy(III) and Eu(III) ions, HL = biphenyl-3'-nitro-3,4',5-tricarboxylic acid, DMF = N,N'-dimethylformamide), were synthesized and characterized. The appearance of temperature-dependent out-of-phase (χ″) signal reveals that complex 1-Dy displays slow magnetic relaxation behavior with the energy barrier (ΔU) of 57 K and a pre-exponential factor (τ) of 3.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
February 2016
Spatial distribution pattern of Populus euphratica and P. pruinosa clonal ramets at three sites was studied, including natural mixed forest of P. euphratica and P.
View Article and Find Full Text PDFLearning from categorical data plays a fundamental role in such areas as pattern recognition, machine learning, data mining, and knowledge discovery. To effectively discover the group structure inherent in a set of categorical objects, many categorical clustering algorithms have been developed in the literature, among which k -modes-type algorithms are very representative because of their good performance. Nevertheless, there is still much room for improving their clustering performance in comparison with the clustering algorithms for the numeric data.
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