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Phytochemical interventions for post-traumatic stress disorder:A cluster co-occurrence network analysis using CiteSpace
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作者 Biao Gao Yi-cui Qu +5 位作者 Meng-yu Cai Yin-yin Zhang Hong-tao Lu Hong-xia Li Yu-xiao Tang Hui Shen 《Journal of Integrative Medicine》 SCIE CAS CSCD 2023年第4期385-396,共12页
Objective:This study investigated trends in the study of phytochemical treatment of post-traumatic stress disorder(PTSD).Methods:The Web of Science database(2007-2022)was searched using the search terms“phytochemical... Objective:This study investigated trends in the study of phytochemical treatment of post-traumatic stress disorder(PTSD).Methods:The Web of Science database(2007-2022)was searched using the search terms“phytochemicals”and“PTSD,”and relevant literature was compiled.Network clustering co-occurrence analysis and qualitative narrative review were conducted.Results:Three hundred and one articles were included in the analysis of published research,which has surged since 2015 with nearly half of all relevant articles coming from North America.The category is dominated by neuroscience and neurology,with two journals,Addictive Behaviors and Drug and Alcohol Dependence,publishing the greatest number of papers on these topics.Most studies focused on psychedelic intervention for PTSD.Three timelines show an“ebb and flow”phenomenon between“substance use/marijuana abuse”and“psychedelic medicine/medicinal cannabis.”Other phytochemicals account for a small proportion of the research and focus on topics like neurosteroid turnover,serotonin levels,and brain-derived neurotrophic factor expression.Conclusion:Research on phytochemicals and PTSD is unevenly distributed across countries/regions,disciplines,and journals.Since 2015,the research paradigm shifted to constitute the mainstream of psychedelic research thus far,leading to the exploration of botanical active ingredients and molecular mechanisms.Other studies focus on anti-oxidative stress and anti-inflammation. 展开更多
关键词 PHYTOCHEMICAL Post-traumatic stress disorder Text analysis Clustering co-occurrence network PSYCHEDELIC
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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Exploring core symptoms and symptom clusters among patients with neuromyelitis optica spectrum disorder: A network analysis 被引量:1
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作者 Hao Liang Jiehan Chen +4 位作者 Lixin Wang Zhuyun Liu Haoyou Xu Min Zhao Xiaopei Zhang 《International Journal of Nursing Sciences》 2025年第2期152-160,共9页
Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to p... Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to participate in this online questionnaire survey.The survey tools included a general information questionnaire and a self-made NMOSD symptoms scale,which included the prevalence,severity,and distress of 29 symptoms.Cluster analysis was used to identify symptom clusters,and network analysis was used to analyze the symptom network and node characteristics and central indicators including strength centrality(r_(s)),closeness centrality(r_(c))and betweeness centrality(r_(b))were used to identify core symptoms and symptom clusters.Results The most common symptom was pain(65.7%),followed by paraesthesia(65.0%),fatigue(65.0%),easy awakening(63.6%).Regarding the burden level of symptoms,pain was the most burdensome symptom,followed by paraesthesia,easy awakening,fatigue,and difficulty falling asleep.Six clusters were identified:somatosensory,motor,visual,and memory symptom clusters,bladder and rectum symptom clusters,sleep symptoms clusters,and neuropsychological symptom clusters.Fatigue(r_(s)=12.39,r_(b)=68.00,r_(c)=0.02)was the most central and prominent bridge symptom,and motor symptom cluster(r_(s)=2.68,r_(c)=0.10)was the most central symptom cluster among the six clusters.Conclusions Our study demonstrated the necessity of symptom management targeting fatigue,pain,and motor symptom cluster in patients with NMOSD. 展开更多
关键词 Neuromyelitis optica spectrum disorder network analysis SYMPTOM Symptom clusters NURSING
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Possible Classifications of Social Network Addiction:A Latent Profile Analysis of Chinese College Students 被引量:1
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作者 Lin Luo Junfeng Yuan +4 位作者 Yanling Wang Rui Zhu HuilinXu Siyuan Bi Zhongge Zhang 《International Journal of Mental Health Promotion》 2025年第6期863-876,共14页
Objectives:SocialNetworkAddiction(SNA)is becoming increasingly prevalent among college students;however,there remains a lack of consensus regarding the measurement tools and their optimal cutoff score.This study aims ... Objectives:SocialNetworkAddiction(SNA)is becoming increasingly prevalent among college students;however,there remains a lack of consensus regarding the measurement tools and their optimal cutoff score.This study aims to validate the 21-item SocialNetwork Addiction Scale-Chinese(SNAS-C)in its Chinese version and to determine its optimal cutoff score for identifying potential SNA cases within the college student population.Methods:A crosssectional survey was conducted,recruiting 3387 college students.Latent profile analysis(LPA)and receiver operating characteristic(ROC)curve analysis were employed to establish the optimal cutoff score for the validated 21-item SNAS-C.Results:Three profile models were selected based on multiple statistical criteria,classifying participants into low-risk,moderate-risk,and high-risk groups.The highest-risk group was defined as“positive”for SNA,while the remaining groups were considered“negative”,serving as the reference standard for ROC analysis.The optimal cutoff score was determined to be 72(sensitivity:98.2%,specificity:96.86%),with an overall classification accuracy of 97.0%.The“positive”group reported significantly higher frequency of social network usage,greater digitalmedia dependence scores,and a higher incidence of network addiction.Conclusion:This study identified the optimal cutoff score for the SNAS-C as≥72,demonstrating high sensitivity,specificity,and diagnostic accuracy.This threshold effectively distinguishes between high-risk and low-risk SNA. 展开更多
关键词 Social network addiction mental health latent profile analysis(LPA) receiver operating characteristic(ROC) social networking addiction scale-Chinese(SNAS-C)
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Aspect-Level Sentiment Analysis of Bi-Graph Convolutional Networks Based on Enhanced Syntactic Structural Information
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作者 Junpeng Hu Yegang Li 《Journal of Computer and Communications》 2025年第1期72-89,共18页
Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dep... Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dependent syntactic trees, which improves the classification performance of the models to some extent. However, the technical limitations of dependent syntactic trees can introduce considerable noise into the model. Meanwhile, it is difficult for a single graph convolutional network to aggregate both semantic and syntactic structural information of nodes, which affects the final sentence classification. To cope with the above problems, this paper proposes a bi-channel graph convolutional network model. The model introduces a phrase structure tree and transforms it into a hierarchical phrase matrix. The adjacency matrix of the dependent syntactic tree and the hierarchical phrase matrix are combined as the initial matrix of the graph convolutional network to enhance the syntactic information. The semantic information feature representations of the sentences are obtained by the graph convolutional network with a multi-head attention mechanism and fused to achieve complementary learning of dual-channel features. Experimental results show that the model performs well and improves the accuracy of sentiment classification on three public benchmark datasets, namely Rest14, Lap14 and Twitter. 展开更多
关键词 Aspect-Level Sentiment analysis Sentiment Knowledge Multi-Head Attention Mechanism Graph Convolutional networks
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Optimization of Park System in Haidian District,Beijing Based on Social Network Analysis
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作者 WU Haotian CAO Ying 《Journal of Landscape Research》 2025年第2期11-16,共6页
The construction of“park cities”requires a systematic thinking to coordinate the networked development of park system and break through the limitation of emphasizing scale and grade and neglecting dynamic correlatio... The construction of“park cities”requires a systematic thinking to coordinate the networked development of park system and break through the limitation of emphasizing scale and grade and neglecting dynamic correlation in traditional planning.Taking Haidian District of Beijing as an example,the social network analysis method is introduced to construct the network model of park green spaces.Through indicators such as clustering coefficient,network density and node centrality,the characteristics of its spatial structure and hierarchical relationship are analyzed.It is found that the network integrity presents the characteristics of“highly local concentration and global fragmentation”,fragmented park green space network and missing spatial connection,isolated clusters and collaborative failure,as well as the spatial mismatch between population and resource supply and demand.Hierarchical issues include“structural imbalance and functional disorder”,disorder between network hierarchy and park level,misalignment of functional hierarchy leading to weakened network risk resistance capacity,and a relatively dense distribution of core nodes,etc.In response to the above problems,a multi-level spatial intervention strategy should be adopted to solve the overall problem of the network.Meanwhile,it is needed to clarify the positioning of a park itself and improve the hierarchical system,so as to construct a multi-level and multi-scale park green space network,contribute to the construction of a park city,and provide residents with more diverse activity venues. 展开更多
关键词 Urban park system Social network analysis Haidian District BEIJING Park network structure
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Distribution of Traditional Chinese Medicine Syndromes and Syndrome Elements of Chronic Heart Failure Based on Network Analysis and Hierarchical Cluster Analysis
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作者 ZHOU Yi HUANG Pinxian +1 位作者 LI Xiaoqian HE Jiancheng 《Chinese Medicine and Culture》 2025年第1期50-60,共11页
Traditional Chinese medicine(TCM)has played a significant role in the prevention and treatment of chronic heart failure(CHF).To study TCM diagnosis of CHF,a total of 278 Chinese clinical research articles on the study... Traditional Chinese medicine(TCM)has played a significant role in the prevention and treatment of chronic heart failure(CHF).To study TCM diagnosis of CHF,a total of 278 Chinese clinical research articles on the study of CHF syndromes in recent 40 years retrieved from Web of Science,Scopus,Pub Med,Embase,CNKI,Wanfang Data,Cq VIP,and Sino Med.According to cumulative frequency analysis,network analysis,and hierarchical cluster analysis,the study found the distribution of CHF syndromes was syndrome of qi deficiency with blood stasis,syndrome of qi and yin deficiency,syndrome of yang deficiency with water flooding,syndrome of heart blood stasis obstruction,syndrome of turbid phlegm,and syndrome of collapse due to primordial yang deficiency.The syndrome elements on location of illness were heart,kidney,lung,and spleen.The syndrome elements on nature of illness were qi deficiency,blood stasis,yang deficiency,yin deficiency,water retention,and turbid phlegm.These findings can provide reference to the research on diagnosis and treatment of CHF,and contribute to the study on syndrome standardization and objective research of TCM diagnosis. 展开更多
关键词 Chronic heart failure Traditional Chinese medicine Hierarchical cluster analysis network analysis SYNDROME Syndrome differentiation Syndrome element
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Drivers influencing the adoption of cryptocurrency: a social network analysis approach
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作者 K.Kajol Srijanani Devarakonda +1 位作者 Ranjit Singh H.Kent Baker 《Financial Innovation》 2025年第1期2103-2127,共25页
Cryptocurrency has gained popularity as a potential new global payment method.It has the potential to be faster,cheaper,and more secure than existing payment networks,making it a game-changer in the global economy.How... Cryptocurrency has gained popularity as a potential new global payment method.It has the potential to be faster,cheaper,and more secure than existing payment networks,making it a game-changer in the global economy.However,more research is needed to identify the factors driving cryptocurrency adoption and understand its impact.We use social network analysis(SNA)to identify the influencing factors and reveal the impact of each on cryptocurrency adoption.Our analysis initially revealed 44 influential factors,which were later reduced to 25 factors,each exerting a different influence.Based on the SNA,we classify these factors into highly,moderately,and least influential categories.Discomfort and optimism are the most influential determinants of adoption.Moderately influential factors include trust,risk,relative advantage,social influence,and perceived behavioral control.Price/value,facilitating conditions,compatibility,and usefulness are the least influential.The factors affecting cryptocurrency adoption are interdependent.Our findings can help policymakers understand the factors influencing cryptocurrency adoption and aid in developing appropriate legal frameworks for cryptocurrency use. 展开更多
关键词 Cryptocurrency Social network analysis(SNA) Systematic review Delphi technique
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Psychometric Properties of the Shortened Committed Action Questionnaire(CAQ-8):Evidence from Classical Test Theory and Network Analysis
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作者 Haiyan Hu Shuanghu Fang +1 位作者 Qilin Zheng Dongyan Ding 《International Journal of Mental Health Promotion》 2025年第1期65-76,共12页
Objectives:This study aimed to assess the reliability and validity of the abbreviated Committed Action Questionnaire(CAQ-8)in a cohort of 1635 Chinese university students.Methods:Participants completed the Chinese ver... Objectives:This study aimed to assess the reliability and validity of the abbreviated Committed Action Questionnaire(CAQ-8)in a cohort of 1635 Chinese university students.Methods:Participants completed the Chinese version of the CAQ-8 along with other standardized measures,including the Acceptance and Action Questionnaire-II(AAQ-II),the Valuing Questionnaire(VQ),the Satisfaction with Life Scale(SWLS),the Depression Anxiety Stress Scales(DASS-21),and the World Health Organization Fiveitem Well-Being Index(WHO-5).A retest was conducted one month later with 300 valid responses.Results:Exploratory factor analysis(n=818)identified a 2-factor structure,confirmed through validated factor analysis(n=817),showing good fit indices(CFI=0.990,RMSEA=0.040).Measurement equivalence across genders was established.The CAQ-8 showed significant positive correlations with life satisfaction,mental health,and values,and negative correlations with depression,anxiety,stress,and experiential avoidance.The scale demonstrated good internal consistency(Cronbach’sα=0.76)and retest reliability(ICC=0.70).Network analysis confirmed the robustness of the 2-factor model,with item 4 in CAQ-8 identified as a core item.Conclusion:The CAQ-8 is a reliable and valid tool for measuring committed action within the psychological flexibility model in Chinese populations. 展开更多
关键词 Acceptance and commitment therapy psychological flexibility committed action network analysis RELIABILITY validity
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Pharmacodynamic evaluation and network pharmacology analysis of a novel anti-heat stress Chinese herbal formula
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作者 Hanfei Wang Shuyi Xu +5 位作者 Haiyang Mao Boyu Wang Yanping Feng Awais Ihsan Shijun Li Xu Wang 《Animal Diseases》 2025年第2期248-266,共19页
Frequent extreme heat events around the world not only pose a major threat to human health but also cause significant economic losses to the livestock industry.The existing management practices are insufficient to ful... Frequent extreme heat events around the world not only pose a major threat to human health but also cause significant economic losses to the livestock industry.The existing management practices are insufficient to fully prevent heat stress with an urgent need to develop preventive medicines.The aim of this study was to develop an antiheat stress Chinese herbal formula(CHF)via big data analysis techniques and to evaluate its anti-heat stress effect and mechanism of action via pharmacodynamic evaluation and network pharmacology analysis.Many anti-heat stress CHFs were collected from the Chinese National Knowledge Infrastructure(CNKI)database.Three alternative CHFs were obtained via unsupervised entropy hierarchical clustering analysis,and the most effective CHF against heat stress,Shidi Jieshu decoction(SJD),was obtained by screening in a mouse heat stress model.In dry and hot environments,SJD significantly improved the heat tolerance of AA broilers by 4-6℃.In a humid and hot environment,pretreatment with 2%SJD resulted in 100%survival of Wenchang chickens at high temperatures.The main active ingredients of SJD were identified as muntjacoside E,timosaponin C,macrostemonoside H and mangiferin via ultraperformance liquid chromatography/mass spectrometry(UPLC/MS)and database comparison.The active ingredients of SJD were found to target tumor necrosis factor-α(TNF-α),signal transducer activator of transcription 3(STAT3)and epidermal growth factor receptor(EGFR).Finally,the safety of the new formulation was assessed in an acute oral toxicity study in rats.The SJDs developed in this study provide a new option for the prevention of heat stress in animal husbandry and offer new insights for further research on anti-heat stress. 展开更多
关键词 Hot weather Heat stress Big data analysis technology network pharmacology Molecular docking CHICKEN
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Cascading failure analysis of an interdependent network with power-combat coupling
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作者 WANG Yang TAO Junyong +2 位作者 ZHANG Yun’an BAI Guanghan DUI Hongyan 《Journal of Systems Engineering and Electronics》 2025年第2期405-422,共18页
Cutting off or controlling the enemy’s power supply at critical moments or strategic locations may result in a cascade failure,thus gaining an advantage in a war.However,the exist-ing cascading failure modeling analy... Cutting off or controlling the enemy’s power supply at critical moments or strategic locations may result in a cascade failure,thus gaining an advantage in a war.However,the exist-ing cascading failure modeling analysis of interdependent net-works is insufficient for describing the load characteristics and dependencies of subnetworks,and it is difficult to use for model-ing and failure analysis of power-combat(P-C)coupling net-works.This paper considers the physical characteristics of the two subnetworks and studies the mechanism of fault propaga-tion between subnetworks and across systems.Then the surviv-ability of the coupled network is evaluated.Firstly,an integrated modeling approach for the combat system and power system is predicted based on interdependent network theory.A heteroge-neous one-way interdependent network model based on proba-bility dependence is constructed.Secondly,using the operation loop theory,a load-capacity model based on combat-loop betweenness is proposed,and the cascade failure model of the P-C coupling system is investigated from three perspectives:ini-tial capacity,allocation strategy,and failure mechanism.Thirdly,survivability indexes based on load loss rate and network sur-vival rate are proposed.Finally,the P-C coupling system is con-structed based on the IEEE 118-bus system to demonstrate the proposed method. 展开更多
关键词 cascading failure survivability analysis interdepen-dent network power-combat(P-C)coupling.
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Sex and age differences in depression and anxiety networks among adolescents with idiopathic scoliosis:A network analysis
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作者 Shu-Wen Dong Lei Yang +8 位作者 Yi-Fan Lin Li-Wen Yang Dan Li Li-Wan Zhu Cai-Yun Zhang Yan-Zhi Li Wan-Xin Wang Ci-Yong Lu Bin Yan 《World Journal of Psychiatry》 2025年第3期261-271,共11页
BACKGROUND Depression and anxiety are prevalent psychological challenges among patients with adolescent idiopathic scoliosis(AIS),affecting individuals across both sex and age groups.AIM To explore the network structu... BACKGROUND Depression and anxiety are prevalent psychological challenges among patients with adolescent idiopathic scoliosis(AIS),affecting individuals across both sex and age groups.AIM To explore the network structure of depression and anxiety symptoms,with a focus on identifying differences at the symptom level between sex and age subgroups.METHODS A total of 1955 participants diagnosed with AIS aged 10-18 years were assessed using the Patient Health Questionnaire Depression Scale(PHO-9)and the Generalized Anxiety Disorder Scale(GAD-7),and 765 patients exhibiting PHQ-9 or GAD-7 scores ≥ 5 were enrolled in our study. Network analysis and network comparison tests were utilized toconstruct and compare the depression-anxiety symptoms networks among sex and age subgroups.RESULTSThe results revealed GAD3 “Excessive worry” and PHQ2 “Sad mood” were the most significant central symptomsin all subgroups, while “Sad mood” had higher strength than “Excessive worry” in the lower age group. In thenetwork comparisons, the female network exhibited tighter connectivity, especially on GAD6 “Irritability” andGAD2 “Uncontrollable worry”, while only PHQ3 “Sleep” and PHQ9 “Suicidal ideation” had differences at thelocal level in the lower age group.CONCLUSIONSeveral interventions targeting excessive worry and sad mood could reduce the risk of depression and anxietysymptoms in the AIS population. Furthermore, specific anxiety symptoms in females, along with sleep disturbancesand suicidal ideation in the lower age group, should be addressed at an early stage to prevent significantdisruptions in mental health trajectories. 展开更多
关键词 Adolescent idiopathic scoliosis network analysis Depression and anxiety symptoms Age difference Sex difference
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TGICP:A Text-Gated Interaction Network with Inter-Sample Commonality Perception for Multimodal Sentiment Analysis
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作者 Erlin Tian Shuai Zhao +3 位作者 Min Huang Yushan Pan Yihong Wang Zuhe Li 《Computers, Materials & Continua》 2025年第10期1427-1456,共30页
With the increasing importance of multimodal data in emotional expression on social media,mainstream methods for sentiment analysis have shifted from unimodal to multimodal approaches.However,the challenges of extract... With the increasing importance of multimodal data in emotional expression on social media,mainstream methods for sentiment analysis have shifted from unimodal to multimodal approaches.However,the challenges of extracting high-quality emotional features and achieving effective interaction between different modalities remain two major obstacles in multimodal sentiment analysis.To address these challenges,this paper proposes a Text-Gated Interaction Network with Inter-Sample Commonality Perception(TGICP).Specifically,we utilize a Inter-sample Commonality Perception(ICP)module to extract common features from similar samples within the same modality,and use these common features to enhance the original features of each modality,thereby obtaining a richer and more complete multimodal sentiment representation.Subsequently,in the cross-modal interaction stage,we design a Text-Gated Interaction(TGI)module,which is text-driven.By calculating the mutual information difference between the text modality and nonverbal modalities,the TGI module dynamically adjusts the influence of emotional information from the text modality on nonverbal modalities.This helps to reduce modality information asymmetry while enabling full cross-modal interaction.Experimental results show that the proposed model achieves outstanding performance on both the CMU-MOSI and CMU-MOSEI baseline multimodal sentiment analysis datasets,validating its effectiveness in emotion recognition tasks. 展开更多
关键词 Multi-modal sentiment analysis multi-modal fusion graph convolutional networks inter-sample commonality perception gated interaction
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A High-Order Modulation Signal ClassificationMethod Based on a Fourier Analysis NetworkIntegrated with an Attention Mechanism
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作者 Yuepeng Li Xiaogang Tang +2 位作者 Binquan Zhang Lu Wang Hao Huan 《Journal of Beijing Institute of Technology》 2025年第4期350-361,共12页
In modern wireless communication and electromagnetic control,automatic modulationclassification(AMC)of orthogonal frequency division multiplexing(OFDM)signals plays animportant role.However,under Doppler frequency shi... In modern wireless communication and electromagnetic control,automatic modulationclassification(AMC)of orthogonal frequency division multiplexing(OFDM)signals plays animportant role.However,under Doppler frequency shift and complex multipath channel conditions,extracting discriminative features from high-order modulation signals and ensuring model inter-pretability remain challenging.To address these issues,this paper proposes a Fourier attention net-work(FAttNet),which combines an attention mechanism with a Fourier analysis network(FAN).Specifically,the method directly converts the input signal to the frequency domain using the FAN,thereby obtaining frequency features that reflect the periodic variations in amplitude and phase.Abuilt-in attention mechanism then automatically calculates the weights for each frequency band,focusing on the most discriminative components.This approach improves both classification accu-racy and model interpretability.Experimental validation was conducted via high-order modulationsimulation using an RF testbed.The results show that under three different Doppler frequencyshifts and complex multipath channel conditions,with a signal-to-noise ratio of 10 dB,the classifi-cation accuracy can reach 89.1%,90.4%and 90%,all of which are superior to the current main-stream methods.The proposed approach offers practical value for dynamic spectrum access and sig-nal security detection,and it makes important theoretical contributions to the application of deeplearning in complex electromagnetic signal recognition. 展开更多
关键词 orthogonal frequency division multiplexing high order modulated signal automaticmodulation classification Fourier analysis network
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Nonlinear frequency prediction and uncertainty analysis for fully clamped laminates by using a self-developed multi-scale neural networks system
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作者 Yuan LIU Xuan ZHANG +6 位作者 Xibin CAO Jinsheng GUO Zhongxi SHAO Qingyang DENG Pengbo FU Yaodong HOU Haipeng CHEN 《Chinese Journal of Aeronautics》 2025年第9期225-250,共26页
To improve design accuracy and reliability of structures,this study solves the uncertain natural frequencies with consideration for geometric nonlinearity and structural uncertainty.Frequencies of the laminated plate ... To improve design accuracy and reliability of structures,this study solves the uncertain natural frequencies with consideration for geometric nonlinearity and structural uncertainty.Frequencies of the laminated plate with all four edges clamped(CCCC)are derived based on Navier's method and Galerkin's method.The novelty of the current work is that the number of unknowns in the displacement field model of a CCCC plate with free midsurface(CCCC-2 plate)is only three compared with four or five in cases of other exposed methods.The present analytical method is proved to be accurate and reliable by comparing linear natural frequencies and nonlinear natural frequencies with other models available in the open literature.Furthermore,a novel method for analyzing effects of mean values and tolerance zones of uncertain structural parameters on random frequencies is proposed based on a self-developed Multiscale Feature Extraction and Fusion Network(MFEFN)system.Compared with a direct Monte Carlo Simulation(MCS),the MFEFNbased procedure significantly reduces the calculation burden with a guarantee of accuracy.Our research provides a method to calculate nonlinear natural frequencies under two boundary conditions and presentes a surrogate model to predict frequencies for accuracy analysis and optimization design. 展开更多
关键词 Geometric nonlinearity LAMINATES Multiscale feature extraction and fusion networks(MFEFN) Natural frequency Uncertainty analysis
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β-ray induced X-ray spectroscopy for tritium analysis with back propagation neural network
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作者 Hong Huang Zhu An Jing-Jun Zhu 《Nuclear Science and Techniques》 2025年第9期187-198,共12页
β-ray-induced X-ray spectroscopy(BIXS)is a promising technique for tritium analysis that offers several unique advantages,including substantial detection depth,nondestructive testing capabilities,and ease of operatio... β-ray-induced X-ray spectroscopy(BIXS)is a promising technique for tritium analysis that offers several unique advantages,including substantial detection depth,nondestructive testing capabilities,and ease of operation.For thin solid tritium-containing samples with substrates,the currently used BIXS analysis method can measure the tritium depth profile and content when the sample thickness is known.In this study,a backpropagation(BP)neural network algorithm was used to predict the tritium content and thickness of a thin solid tritium-containing sample with substrates and a uniformly distributed tritium profile.A semi-analytical method was used to generate datasets for training and testing the BP neural network.A dataset ofβ-decay X-ray spectra from 420 tritium-containing zirconium models with different known thicknesses and tritium-tozirconium ratios was used as the input data.The corresponding zirconium thicknesses and tritium-to-zirconium ratios served as the output for training and testing the BP neural network.The mean relative errors(MREs)of the zirconium thickness in the training and test datasets were 0.56%and 0.42%,respectively,whereas the MREs of the tritium-to-zirconium ratio were 0.59%and 0.38%,respectively.Furthermore,the trained BP neural network demonstrates excellent predictive capability across various levels of statistical uncertainty.For the experimentalβ-decay X-ray spectra of two tritium-containing samples,the predicted zirconium thicknesses and tritium-to-zirconium ratios showed good agreement with the results obtained through the elastic backscattering spectrometry(EBS). 展开更多
关键词 Tritium analysis β-ray induced X-ray Uniformly distributed tritium Unknown thickness SEMI-ANALYTICAL Back propagation neural network
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Spatio-Temporal Variations in Co-Occurrence Patterns of Fish Communities in Haizhou Bay, China: Null Model Analysis 被引量:1
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作者 WANG Jiao ZHANG Chongliang +3 位作者 XUE Ying CHEN Yong REN Yiping XU Binduo 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1497-1506,共10页
Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patte... Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay. 展开更多
关键词 FISH COMMUNITY Haizhou BAY NULL model analysis SPECIES co-occurrence pattern
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A knowledge discovery method based on analysis of multiple co-occurrence relationships in collections of journal papers 被引量:4
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作者 Hongshen PANG 《Chinese Journal of Library and Information Science》 2012年第4期9-20,共12页
Purpose: This paper explores a method of knowledge discovery by visualizing and analyzing co-occurrence relations among three or more entities in collections of journal articles.Design/methodology/approach: A variety ... Purpose: This paper explores a method of knowledge discovery by visualizing and analyzing co-occurrence relations among three or more entities in collections of journal articles.Design/methodology/approach: A variety of methods such as the model construction,system analysis and experiments are used. The author has improved Morris' crossmapping technique and developed a technique for directly describing,visualizing and analyzing co-occurrence relations among three or more entities in collections of journal articles.Findings: The visualization tools and the knowledge discovery method can efficiently reveal the multiple co-occurrence relations among three entities in collections of journal papers. It can reveal more and in-depth information than analyzing co-occurrence relations between two entities. Therefore,this method can be used for mapping knowledge domain that is manifested in association with the entities from multi-dimensional perspectives and in an all-round way.Research limitations: The technique could only be used to analyze co-occurrence relations of less than three entities at present.Practical implications: This research has expanded the study scope of co-occurrence analysis.The research result has provided a theoretical support for co-occurrence analysis.Originality/value: There has not been a systematic study on co-occurrence relations among multiple entities in collections of journal articles. This research defines multiple co-occurrence and the research scope,develops the visualization analysis tool and designs the analysis model of the knowledge discovery method. 展开更多
关键词 Multiple co-occurrence Visualization analysis Knowledge discovery Research field analysis Embryonic stem cell
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The reflection of hierarchical cluster analysis of co-occurrence matrices in SPSS 被引量:5
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作者 Qiuju ZHOU Fuhai LENG Loet LEYDESDORFF 《Chinese Journal of Library and Information Science》 2015年第2期11-24,共14页
Purpose: To discuss the problems arising from hierarchical cluster analysis of co-occurrence matrices in SPSS, and the corresponding solutions. Design/methodology/approach: We design different methods of using the S... Purpose: To discuss the problems arising from hierarchical cluster analysis of co-occurrence matrices in SPSS, and the corresponding solutions. Design/methodology/approach: We design different methods of using the SPSS hierarchical clustering module for co-occurrence matrices in order to compare these methods. We offer the correct syntax to deactivate the similarity algorithm for clustering analysis within the hierarchical clustering module of SPSS. Findings: When one inputs co-occurrence matrices into the data editor of the SPSS hierarchical clustering module without deactivating the embedded similarity algorithm, the program calculates similarity twice, and thus distorts and overestimates the degree of similarity. Practical implications: We offer the correct syntax to block the similarity algorithm for clustering analysis in the SPSS hierarchical clustering module in the case of co-occurrence matrices. This syntax enables researchers to avoid obtaining incorrect results. Originality/value: This paper presents a method of editing syntax to prevent the default use of a similarity algorithm for SPSS's hierarchical clustering module. This will help researchers, especially those from China, to properly implement the co-occurrence matrix when using SPSS for hierarchical cluster analysis, in order to provide more scientific and rational results. 展开更多
关键词 co-occurrence matrices Hierarchical cluster analysis SPSS Similarity algorithm The syntax editor
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Visual Exploration Research in the Field of Library and Information Based on Co-occurrence Analysis
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作者 Hao Wang 《Proceedings of Business and Economic Studies》 2019年第4期13-17,共5页
Towards current modern society,our country’s library and information science is not only rapid development,but it also has won the favor of many researchers in more than a decade of development.Due to new technology ... Towards current modern society,our country’s library and information science is not only rapid development,but it also has won the favor of many researchers in more than a decade of development.Due to new technology elements and methods are widely used in the discipline of library and information science,cause society our country’s library and information science has entered a new stage with the development of information industry.This paper is based on the research theory of co-occurrence analysis,clustering co-occurrence analysis of references,social network co-occurrence analysis from researchers and research institutions of the field of library and information science,to have more precise and in depth research on the research focus of the library and information science,the authors themselves and the research institutions circumstances over the past few years.At the same time,the theory is used to analyze the effects and analysis of accurate data,to ensure that researchers can analyze the theory of library and information science for a long time. 展开更多
关键词 co-occurrence analysis FIELD of LIBRARY and information VISUALIZATION EXPLORATION RESEARCH
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