期刊文献+
共找到833篇文章
< 1 2 42 >
每页显示 20 50 100
Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy
1
作者 Feng Chen Xi Dong +11 位作者 Zhenhuan Wang Tongrui Wu Liangpeng Wei Yuanyuan Li Kai Zhang Zengguang Ma Chao Tian Jing Li Jingyu Zhao Wei Zhang Aili Liu Hui Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期425-433,共9页
Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and... Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and is not fully understood.Intracellular calcium dynamics have been implicated in temporal lobe epilepsy.However,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice.In this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process.We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes.In particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures.Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠepisodes.In addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced.Intriguingly,it was possible to rescue the altered intracellular calcium dynamics.Via simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were improved.Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades.Furthermore,the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy,thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy. 展开更多
关键词 CA^(2+) calcium signals chemogenetic methods HIPPOCAMPUS primary motor cortex pyramidal neurons temporal lobe epilepsy
下载PDF
The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products
2
作者 Yue SUN Huiling YANG +5 位作者 Hui XIAO Liang FENG Wei CHENG Libo ZHOU Weixi SHU Jingzhe SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期310-324,共15页
The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud typ... The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds. 展开更多
关键词 CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation
下载PDF
Spatiotemporal Prediction of Urban Traffics Based on Deep GNN
3
作者 Ming Luo Huili Dou Ning Zheng 《Computers, Materials & Continua》 SCIE EI 2024年第1期265-282,共18页
Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of ... Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of traffic data.As well as to fulfil both long-termand short-termprediction objectives,a better representation of the temporal dependency and global spatial correlation of traffic data is needed.In order to do this,the Spatiotemporal Graph Neural Network(S-GNN)is proposed in this research as amethod for traffic prediction.The S-GNN simultaneously accepts various traffic data as inputs and investigates the non-linear correlations between the variables.In terms of modelling,the road network is initially represented as a spatiotemporal directed graph,with the features of the samples at the time step being captured by a convolution module.In order to assign varying attention weights to various adjacent area nodes of the target node,the adjacent areas information of nodes in the road network is then aggregated using a graph network.The data is output using a fully connected layer at the end.The findings show that S-GNN can improve short-and long-term traffic prediction accuracy to a greater extent;in comparison to the control model,the RMSE of S-GNN is reduced by about 0.571 to 9.288 and the MAE(Mean Absolute Error)by about 0.314 to 7.678.The experimental results on two real datasets,Pe MSD7(M)and PEMS-BAY,also support this claim. 展开更多
关键词 Urban traffic TRAFFIC temporal correlation GNN PREDICTION
下载PDF
Enhanced Temporal Correlation for Universal Lesion Detection
4
作者 Muwei Jian Yue Jin Hui Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3051-3063,共13页
Universal lesion detection(ULD)methods for computed tomography(CT)images play a vital role in the modern clinical medicine and intelligent automation.It is well known that single 2D CT slices lack spatial-temporal cha... Universal lesion detection(ULD)methods for computed tomography(CT)images play a vital role in the modern clinical medicine and intelligent automation.It is well known that single 2D CT slices lack spatial-temporal characteristics and contextual information compared to 3D CT blocks.However,3D CT blocks necessitate significantly higher hardware resources during the learning phase.Therefore,efficiently exploiting temporal correlation and spatial-temporal features of 2D CT slices is crucial for ULD tasks.In this paper,we propose a ULD network with the enhanced temporal correlation for this purpose,named TCE-Net.The designed TCE module is applied to enrich the discriminate feature representation of multiple sequential CT slices.Besides,we employ multi-scale feature maps to facilitate the localization and detection of lesions in various sizes.Extensive experiments are conducted on the DeepLesion benchmark demonstrate that thismethod achieves 66.84%and 78.18%for FS@0.5 and FS@1.0,respectively,outperforming compared state-of-the-art methods. 展开更多
关键词 Universal lesion detection computational biology medical computing deep learning enhanced temporal correlation
下载PDF
TSCND:Temporal Subsequence-Based Convolutional Network with Difference for Time Series Forecasting
5
作者 Haoran Huang Weiting Chen Zheming Fan 《Computers, Materials & Continua》 SCIE EI 2024年第3期3665-3681,共17页
Time series forecasting plays an important role in various fields, such as energy, finance, transport, and weather. Temporal convolutional networks (TCNs) based on dilated causal convolution have been widely used in t... Time series forecasting plays an important role in various fields, such as energy, finance, transport, and weather. Temporal convolutional networks (TCNs) based on dilated causal convolution have been widely used in time series forecasting. However, two problems weaken the performance of TCNs. One is that in dilated casual convolution, causal convolution leads to the receptive fields of outputs being concentrated in the earlier part of the input sequence, whereas the recent input information will be severely lost. The other is that the distribution shift problem in time series has not been adequately solved. To address the first problem, we propose a subsequence-based dilated convolution method (SDC). By using multiple convolutional filters to convolve elements of neighboring subsequences, the method extracts temporal features from a growing receptive field via a growing subsequence rather than a single element. Ultimately, the receptive field of each output element can cover the whole input sequence. To address the second problem, we propose a difference and compensation method (DCM). The method reduces the discrepancies between and within the input sequences by difference operations and then compensates the outputs for the information lost due to difference operations. Based on SDC and DCM, we further construct a temporal subsequence-based convolutional network with difference (TSCND) for time series forecasting. The experimental results show that TSCND can reduce prediction mean squared error by 7.3% and save runtime, compared with state-of-the-art models and vanilla TCN. 展开更多
关键词 DIFFERENCE data prediction time series temporal convolutional network dilated convolution
下载PDF
IndRT-GCNets: Knowledge Reasoning with Independent Recurrent Temporal Graph Convolutional Representations
6
作者 Yajing Ma Gulila Altenbek Yingxia Yu 《Computers, Materials & Continua》 SCIE EI 2024年第1期695-712,共18页
Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurr... Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurrent Temporal Graph Convolution Networks(IndRT-GCNets)framework to efficiently and accurately capture event attribute information.The framework models the knowledge graph sequences to learn the evolutionary represen-tations of entities and relations within each period.Firstly,by utilizing the temporal graph convolution module in the evolutionary representation unit,the framework captures the structural dependency relationships within the knowledge graph in each period.Meanwhile,to achieve better event representation and establish effective correlations,an independent recurrent neural network is employed to implement auto-regressive modeling.Furthermore,static attributes of entities in the entity-relation events are constrained andmerged using a static graph constraint to obtain optimal entity representations.Finally,the evolution of entity and relation representations is utilized to predict events in the next subsequent step.On multiple real-world datasets such as Freebase13(FB13),Freebase 15k(FB15K),WordNet11(WN11),WordNet18(WN18),FB15K-237,WN18RR,YAGO3-10,and Nell-995,the results of multiple evaluation indicators show that our proposed IndRT-GCNets framework outperforms most existing models on knowledge reasoning tasks,which validates the effectiveness and robustness. 展开更多
关键词 Knowledge reasoning entity and relation representation structural dependency relationship evolutionary representation temporal graph convolution
下载PDF
Hemichorea in patients with temporal lobe infarcts: Two case reports
7
作者 Xu-Dong Wang Xing Li Chun-Lian Pan 《World Journal of Clinical Cases》 SCIE 2024年第4期806-813,共8页
BACKGROUND Hemichorea and other hyperkinetic movement disorders are uncommon present-ations of stroke and are usually secondary to deep infarctions affecting the basal ganglia and thalamus.Therefore,temporal ischemic ... BACKGROUND Hemichorea and other hyperkinetic movement disorders are uncommon present-ations of stroke and are usually secondary to deep infarctions affecting the basal ganglia and thalamus.Therefore,temporal ischemic lesions causing hemichorea are rare.We report the cases of two patients with acute ischemic temporal lobe infarct strokes that presented as hemichorea.CASE SUMMARY Patient 1:An 82-year-old woman presented with a 1-mo history of involuntary movement of the left extremity,which was consistent with hemichorea.Her diffusion-weighted imaging(DWI)revealed an acute ischemic stroke that predominantly affected the right temporal cortex,and magnetic resonance angiography of the head showed significant stenosis of the right middle cerebral artery(MCA).Treatment with 2.5 mg of olanzapine per day was initiated.When she was discharged from the hospital,her symptoms appeared to have improved compared with those previously observed.Twenty-seven days after the first admission,she was readmitted due to acute ischemic stroke.Computed tomogra-phy perfusion showed marked hypoperfusion in the right MCA territory.An emergency transfemoral cerebral angiogram was performed and showed severe stenosis in the M1 segment of the right MCA.After percutaneous transluminal angioplasty was successfully performed,abnormal movements or other neuro-logic problems did not occur.Patient 2:A 76-year-old man was admitted to our hospital for a 7-d history of right-upper-sided involuntary movements.DWI showed an acute patchy ischemic stroke in the left temporal lobe without basal ganglia involvement.Subsequent diffusion tensor imaging confirmed fewer white matter fiber tracts on the left side than on the opposite side.Treatment with 2.5 mg of olanzapine per day improved his condition,and he was discharged.CONCLUSION When acute hemichorea suddenly appears,temporal cortical ischemic stroke should be considered a possible diagnosis.In addition,hemichorea may be a sign of impending cerebral infarction with MCA stenosis. 展开更多
关键词 Acute ischemic stroke temporal ischemic stroke Movement disorders Cortical hemichorea Case report
下载PDF
Multi-Stream Temporally Enhanced Network for Video Salient Object Detection
8
作者 Dan Xu Jiale Ru Jinlong Shi 《Computers, Materials & Continua》 SCIE EI 2024年第1期85-104,共20页
Video salient object detection(VSOD)aims at locating the most attractive objects in a video by exploring the spatial and temporal features.VSOD poses a challenging task in computer vision,as it involves processing com... Video salient object detection(VSOD)aims at locating the most attractive objects in a video by exploring the spatial and temporal features.VSOD poses a challenging task in computer vision,as it involves processing complex spatial data that is also influenced by temporal dynamics.Despite the progress made in existing VSOD models,they still struggle in scenes of great background diversity within and between frames.Additionally,they encounter difficulties related to accumulated noise and high time consumption during the extraction of temporal features over a long-term duration.We propose a multi-stream temporal enhanced network(MSTENet)to address these problems.It investigates saliency cues collaboration in the spatial domain with a multi-stream structure to deal with the great background diversity challenge.A straightforward,yet efficient approach for temporal feature extraction is developed to avoid the accumulative noises and reduce time consumption.The distinction between MSTENet and other VSOD methods stems from its incorporation of both foreground supervision and background supervision,facilitating enhanced extraction of collaborative saliency cues.Another notable differentiation is the innovative integration of spatial and temporal features,wherein the temporal module is integrated into the multi-stream structure,enabling comprehensive spatial-temporal interactions within an end-to-end framework.Extensive experimental results demonstrate that the proposed method achieves state-of-the-art performance on five benchmark datasets while maintaining a real-time speed of 27 fps(Titan XP).Our code and models are available at https://github.com/RuJiaLe/MSTENet. 展开更多
关键词 Video salient object detection deep learning temporally enhanced foreground-background collaboration
下载PDF
Cognitive Disorders, Depression and Anxiety in Temporal Lobe Epilepsy: An Overview
9
作者 Amina Tani Nawal Adali 《Journal of Biosciences and Medicines》 2024年第3期77-93,共17页
Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical inter... Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical intervention due to its refractoriness to antiepileptic drugs (AEDs). Hippocampal sclerosis, a common underlying pathology, often exacerbates the severity by introducing cognitive and emotional challenges. This review delves deeper into the cognitive profile of TLE, along with the risk factors for cognitive disorders, depression, and anxiety in this population. 展开更多
关键词 temporal Lobe Epilepsy Cognitive Disorders ANXIETY DEPRESSION
下载PDF
Discrete Choice Analysis of Temporal Factors on Social Network Growth
10
作者 Kwok-Wai Cheung Yuk Tai Siu 《Intelligent Information Management》 2024年第1期21-34,共14页
Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital w... Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital world. These networks can be viewed as a collection of nodes and edges, where users and their interactions are represented as nodes and the connections between them as edges. Understanding the factors that contribute to the formation of these edges is important for studying network structure and processes. This knowledge can be applied to various areas such as identifying communities, recommending friends, and targeting online advertisements. Several factors, including node popularity and friends-of-friends relationships, influence edge formation and network growth. This research focuses on the temporal activity of nodes and its impact on edge formation. Specifically, the study examines how the minimum age of friends-of-friends edges and the average age of all edges connected to potential target nodes influence the formation of network edges. Discrete choice analysis is used to analyse the combined effect of these temporal factors and other well-known attributes like node degree (i.e., the number of connections a node has) and network distance between nodes. The findings reveal that temporal properties have a similar impact as network proximity in predicting the creation of links. By incorporating temporal features into the models, the accuracy of link prediction can be further improved. 展开更多
关键词 Discrete Choice Models temporal Factors Social Network Link Prediction Network Growth
下载PDF
MicroRNAs as potential biomarkers in temporal lobe epilepsy and mesial temporal lobe epilepsy 被引量:3
11
作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第4期716-726,共11页
Temporal lobe epilepsy is the most common form of focal epilepsy in adults,accounting for one third of all diagnosed epileptic patients,with seizures originating from or involving mesial temporal structures such as th... Temporal lobe epilepsy is the most common form of focal epilepsy in adults,accounting for one third of all diagnosed epileptic patients,with seizures originating from or involving mesial temporal structures such as the hippocampus,and many of these patients being refractory to treatment with anti-epileptic drugs.Temporal lobe epilepsy is the most common childhood neurological disorder and,compared with adults,the symptoms are greatly affected by age and brain development.Diagnosis of temporal lobe epilepsy relies on clinical examination,patient history,electroencephalographic recordings,and brain imaging.Misdiagnosis or delay in diagnosis is common.A molecular biomarker that could distinguish epilepsy from healthy subjects and other neurological conditions would allow for an earlier and more accurate diagnosis and appropriate treatment to be initiated.Among possible biomarkers of pathological changes as well as potential therapeutic targets in the epileptic brain are micro RNAs.Most of the recent studies had performed micro RNA profiling in body fluids such as blood plasma and blood serum and brain tissues such as temporal cortex tissue and hippocampal tissue.A large number of micro RNAs were dysregulated when compared to healthy controls and with some overlap between individual studies that could serve as potential biomarkers.For example,in adults with temporal lobe epilepsy,possible biomarkers are miR-199a-3p in blood plasma and miR-142-5p in blood plasma and blood serum.In adults with mesial temporal lobe epilepsy,possible biomarkers are miR-153 in blood plasma and miR-145-3p in blood serum.However,in many of the studies involving patients who receive one or several anti-epileptic drugs,the influence of these on micro RNA expression in body fluids and brain tissues is largely unknown.Further studies are warranted with children with temporal lobe epilepsy and consideration should be given to utilizing mouse or rat and non-human primate models of temporal lobe epilepsy.The animal models could be used to confirm micro RNA findings in human patients and to test the effects of targeting specific micro RNAs on disease progression and behavior. 展开更多
关键词 ADULTS biomarkers blood plasma blood serum children hippocampal tissue mesial temporal lobe epilepsy microRNA temporal cortical tissue temporal lobe epilepsy
下载PDF
STGSA:A Novel Spatial-Temporal Graph Synchronous Aggregation Model for Traffic Prediction 被引量:1
12
作者 Zebing Wei Hongxia Zhao +5 位作者 Zhishuai Li Xiaojie Bu Yuanyuan Chen Xiqiao Zhang Yisheng Lv Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期226-238,共13页
The success of intelligent transportation systems relies heavily on accurate traffic prediction,in which how to model the underlying spatial-temporal information from traffic data has come under the spotlight.Most exi... The success of intelligent transportation systems relies heavily on accurate traffic prediction,in which how to model the underlying spatial-temporal information from traffic data has come under the spotlight.Most existing frameworks typically utilize separate modules for spatial and temporal correlations modeling.However,this stepwise pattern may limit the effectiveness and efficiency in spatial-temporal feature extraction and cause the overlook of important information in some steps.Furthermore,it is lacking sufficient guidance from prior information while modeling based on a given spatial adjacency graph(e.g.,deriving from the geodesic distance or approximate connectivity),and may not reflect the actual interaction between nodes.To overcome those limitations,our paper proposes a spatial-temporal graph synchronous aggregation(STGSA)model to extract the localized and long-term spatial-temporal dependencies simultaneously.Specifically,a tailored graph aggregation method in the vertex domain is designed to extract spatial and temporal features in one graph convolution process.In each STGSA block,we devise a directed temporal correlation graph to represent the localized and long-term dependencies between nodes,and the potential temporal dependence is further fine-tuned by an adaptive weighting operation.Meanwhile,we construct an elaborated spatial adjacency matrix to represent the road sensor graph by considering both physical distance and node similarity in a datadriven manner.Then,inspired by the multi-head attention mechanism which can jointly emphasize information from different r epresentation subspaces,we construct a multi-stream module based on the STGSA blocks to capture global information.It projects the embedding input repeatedly with multiple different channels.Finally,the predicted values are generated by stacking several multi-stream modules.Extensive experiments are constructed on six real-world datasets,and numerical results show that the proposed STGSA model significantly outperforms the benchmarks. 展开更多
关键词 Deep learning graph neural network(GNN) multistream spatial-temporal feature extraction temporal graph traffic prediction
下载PDF
Assessing spatiotemporal variations of forest carbon density using bi-temporal discrete aerial laser scanning data in Chinese boreal forests
13
作者 Zhiyong Qi Shiming Li +3 位作者 Yong Pang Guang Zheng Dan Kong Zengyuan Li 《Forest Ecosystems》 SCIE CSCD 2023年第5期547-560,共14页
Assessing the changes in forest carbon stocks over time is critical for monitoring carbon dynamics,estimating the balance between carbon uptake and release from forests,and providing key insights into climate change m... Assessing the changes in forest carbon stocks over time is critical for monitoring carbon dynamics,estimating the balance between carbon uptake and release from forests,and providing key insights into climate change mitigation.In this study,we quantitatively characterized spatiotemporal variations in aboveground carbon density(ACD)in boreal natural forests in the Greater Khingan Mountains(GKM)region using bi-temporal discrete aerial laser scanning(ALS)data acquired in 2012 and 2016.Moreover,we evaluated the transferability of the proposed design model using forest field plot data and produced a wall-to-wall map of ACD changes for the entire study area from 2012 to 2016 at a grid size of 30 m.In addition,we investigated the relationships between carbon dynamics and the dominant tree species,age groups,and topography of undisturbed forested areas to better understand ACD variations by employing heterogeneous forest canopy structural characteristics.The results showed that the performance of the temporally transferable model(R^(2)=0.87,rRMSE=18.25%),which included stable variables,was statistically equivalent to that obtained from the model fitted directly by the 2016 field plots(R^(2)=0.87,rRMSE=17.47%).The average rate of change in carbon sequestration across the entire study region was 1.35 Mg⋅ha^(-1)⋅year^(-1) based on the changes in ALS-based ACD values over the course of four years.The relative change rates of ACD decreased as the elevation increased,with the highest and lowest ACD growth rates occurring in the middle-aged and mature forest stands,respectively.The Gini coefficient,which represents forest canopy surface structure heterogeneity,is sensitive to carbon dynamics and is a reliable predictor of the relative change rate of ACD.This study demonstrated the applicability of bi-temporal ALS for predicting forest carbon dynamics and fine-scale spatial change patterns.Our research contributed to a better understanding of the in-fluence of remote sensing-derived environmental variables on forest carbon dynamic patterns and the development of context-specific management approaches to increase forest carbon stocks. 展开更多
关键词 Aboveground carbon density Bi-temporal ALS Carbon dynamics temporal transferability Gini coefficient
下载PDF
Fine-Grained Action Recognition Based on Temporal Pyramid Excitation Network
14
作者 Xuan Zhou Jianping Yi 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2103-2116,共14页
Mining more discriminative temporal features to enrich temporal context representation is considered the key to fine-grained action recog-nition.Previous action recognition methods utilize a fixed spatiotemporal windo... Mining more discriminative temporal features to enrich temporal context representation is considered the key to fine-grained action recog-nition.Previous action recognition methods utilize a fixed spatiotemporal window to learn local video representation.However,these methods failed to capture complex motion patterns due to their limited receptive field.To solve the above problems,this paper proposes a lightweight Temporal Pyramid Excitation(TPE)module to capture the short,medium,and long-term temporal context.In this method,Temporal Pyramid(TP)module can effectively expand the temporal receptive field of the network by using the multi-temporal kernel decomposition without significantly increasing the computational cost.In addition,the Multi Excitation module can emphasize temporal importance to enhance the temporal feature representation learning.TPE can be integrated into ResNet50,and building a compact video learning framework-TPENet.Extensive validation experiments on several challenging benchmark(Something-Something V1,Something-Something V2,UCF-101,and HMDB51)datasets demonstrate that our method achieves a preferable balance between computation and accuracy. 展开更多
关键词 Fine-grained action recognition temporal pyramid excitation module temporal receptive multi-excitation module
下载PDF
A Spatio-Temporal Heterogeneity Data Accuracy Detection Method Fused by GCN and TCN
15
作者 Tao Liu Kejia Zhang +4 位作者 Jingsong Yin Yan Zhang Zihao Mu Chunsheng Li Yanan Hu 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2563-2582,共20页
Spatio-temporal heterogeneous data is the database for decisionmaking in many fields,and checking its accuracy can provide data support for making decisions.Due to the randomness,complexity,global and local correlatio... Spatio-temporal heterogeneous data is the database for decisionmaking in many fields,and checking its accuracy can provide data support for making decisions.Due to the randomness,complexity,global and local correlation of spatiotemporal heterogeneous data in the temporal and spatial dimensions,traditional detection methods can not guarantee both detection speed and accuracy.Therefore,this article proposes a method for detecting the accuracy of spatiotemporal heterogeneous data by fusing graph convolution and temporal convolution networks.Firstly,the geographic weighting function is introduced and improved to quantify the degree of association between nodes and calculate the weighted adjacency value to simplify the complex topology.Secondly,design spatiotemporal convolutional units based on graph convolutional neural networks and temporal convolutional networks to improve detection speed and accuracy.Finally,the proposed method is compared with three methods,ARIMA,T-GCN,and STGCN,in real scenarios to verify its effectiveness in terms of detection speed,detection accuracy and stability.The experimental results show that the RMSE,MAE,and MAPE of this method are the smallest in the cases of simple connectivity and complex connectivity degree,which are 13.82/12.08,2.77/2.41,and 16.70/14.73,respectively.Also,it detects the shortest time of 672.31/887.36,respectively.In addition,the evaluation results are the same under different time periods of processing and complex topology environment,which indicates that the detection accuracy of this method is the highest and has good research value and application prospects. 展开更多
关键词 Spatiotemporal heterogeneity data data accuracy complex topology structure graph convolutional networks temporal convolutional networks
下载PDF
Dynamic Spatio-Temporal Modeling in Disease Mapping
16
作者 Flavian Awere Otieno Cox Lwaka Tamba +1 位作者 Justin Obwoge Okenye Luke Akong’o Orawo 《Open Journal of Statistics》 2023年第6期893-916,共24页
Spatio-temporal models are valuable tools for disease mapping and understanding the geographical distribution of diseases and temporal dynamics. Spatio-temporal models have been proven empirically to be very complex a... Spatio-temporal models are valuable tools for disease mapping and understanding the geographical distribution of diseases and temporal dynamics. Spatio-temporal models have been proven empirically to be very complex and this complexity has led many to oversimply and model the spatial and temporal dependencies independently. Unlike common practice, this study formulated a new spatio-temporal model in a Bayesian hierarchical framework that accounts for spatial and temporal dependencies jointly. The spatial and temporal dependencies were dynamically modelled via the matern exponential covariance function. The temporal aspect was captured by the parameters of the exponential with a first-order autoregressive structure. Inferences about the parameters were obtained via Markov Chain Monte Carlo (MCMC) techniques and the spatio-temporal maps were obtained by mapping stable posterior means from the specific location and time from the best model that includes the significant risk factors. The model formulated was fitted to both simulation data and Kenya meningitis incidence data from 2013 to 2019 along with two covariates;Gross County Product (GCP) and average rainfall. The study found that both average rainfall and GCP had a significant positive association with meningitis occurrence. Also, regarding geographical distribution, the spatio-temporal maps showed that meningitis is not evenly distributed across the country as some counties reported a high number of cases compared with other counties. 展开更多
关键词 Spatio-temporal Model Matern Exponential Covariance Function Spatial and temporal Dependencies Markov Chain Monte Carlo (MCMC)
下载PDF
Activation of medial septum cholinergic neurons restores cognitive function in temporal lobe epilepsy 被引量:1
17
作者 Junzi Chen Yu Wang +5 位作者 Cong Chen Qingyang Zhang Shuang Wang Yi Wang Jiajia Fang Ying Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2459-2465,共7页
Cognitive impairment is the most common complication in patients with temporal lobe epilepsy with hippocampal scle rosis.There is no effective treatment for cognitive impairment.Medial septum cholinergic neurons have ... Cognitive impairment is the most common complication in patients with temporal lobe epilepsy with hippocampal scle rosis.There is no effective treatment for cognitive impairment.Medial septum cholinergic neurons have been reported to be a potential target for controlling epileptic seizures in tempo ral lobe epile psy.However,their role in the cognitive impairment of temporal lobe epilepsy remains unclear.In this study,we found that patients with temporal lobe epile psy with hippocampal sclerosis had a low memory quotient and severe impairment in verbal memory,but had no impairment in nonverbal memory.The cognitive impairment was slightly correlated with reduced medial septum volume and medial septum-hippocampus tra cts measured by diffusion tensor imaging.In a mouse model of chronic temporal lobe epilepsy induced by kainic acid,the number of medial septum choline rgic neurons was reduced and acetylcholine release was reduced in the hippocampus.Furthermore,selective apoptosis of medial septum cholinergic neurons mimicked the cognitive deficits in epileptic mice,and activation of medial septum cholinergic neurons enhanced hippocampal acetylcholine release and restored cognitive function in both kainic acid-and kindling-induced epile psy models.These res ults suggest that activation of medial septum cholinergic neurons reduces cognitive deficits in temporal lobe epilepsy by increasing acetylcholine release via projections to the hippocampus. 展开更多
关键词 ACETYLCHOLINE cholinergic neuron cognitive deficit diffusion tensor imaging hippocampal sclerosis HIPPOCAMPUS medial septum MICRODIALYSIS OPTOGENETICS temporal lobe epilepsy
下载PDF
Early-Awareness Collision Avoidance in Optimal Multi-Agent Path Planning With Temporal Logic Specifications 被引量:1
18
作者 Yiwei Zheng Aiwen Lai +1 位作者 Xiao Yu Weiyao Lan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1346-1348,共3页
Dear Editor,This letter investigates a multi-agent path planning problem in a road network with the requirement of avoiding collisions among all agents in the partitioned environment.We first abstract the agents to a ... Dear Editor,This letter investigates a multi-agent path planning problem in a road network with the requirement of avoiding collisions among all agents in the partitioned environment.We first abstract the agents to a set of transition systems,and construct a team transition system from these individual systems.A mechanism is designed for the team transition system to detect all collisions within the synthesized run. 展开更多
关键词 agent temporal INDIVIDUAL
下载PDF
Flight parameter calculation method of multi-projectiles using temporal and spatial information constraint 被引量:1
19
作者 Han-shan Li Xiao-qian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期63-75,共13页
The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these weapons.The characteristic... The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these weapons.The characteristics of multiple projectiles are high randomness and large numbers launched in a short period of time,making it very difficult to obtain the real dispersion parameters of the projectiles due to the occlusion or coincidence of multiple projectiles.Using six intersecting-screen testing system,in this paper,we propose an association recognition and matching algorithm of multiple projectiles using a temporal and spatial information constraint mechanism.We extract the output signal from each detection screen and then use the wavelet transform to process the output signal.We present a method to identify and extract the time values on which the projectiles pass through the detection screens using the wavelet transform modulus maximum theory.We then use the correlation of the output signals of three parallel detection screens to establish a correlation coefficient recognition constraint function for the multiple projectiles.Based on the premise of linear projectile motion,we establish a temporal and spatial constraint matching model using the projectile’s position coordinates in each detection screen and the projectile’s time constraints within the multiple intersecting-screen geometry.We then determine the time values of the multiple projectiles in each detection screen using an iterative search cycle registration,and finally obtain the flight parameters for the multiple projectiles in the presence of uncertainty.The proposed method and algorithm were verified experimentally and can solve the problem of uncertainty in projectiles flight parameter under different multiple projectile firing states. 展开更多
关键词 Six detection screen array Multi-projectile Recognition and matching temporal and spatial information constraint Wavelet transform
下载PDF
An Influence Maximization Algorithm Based on Improved K-Shell in Temporal Social Networks 被引量:1
20
作者 Wenlong Zhu Yu Miao +2 位作者 Shuangshuang Yang Zuozheng Lian Lianhe Cui 《Computers, Materials & Continua》 SCIE EI 2023年第5期3111-3131,共21页
Influence maximization of temporal social networks(IMT)is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely spread.To solve the IMT ... Influence maximization of temporal social networks(IMT)is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely spread.To solve the IMT problem,we propose an influence maximization algorithm based on an improved K-shell method,namely improved K-shell in temporal social networks(KT).The algorithm takes into account the global and local structures of temporal social networks.First,to obtain the kernel value Ks of each node,in the global scope,it layers the network according to the temporal characteristic of nodes by improving the K-shell method.Then,in the local scope,the calculation method of comprehensive degree is proposed to weigh the influence of nodes.Finally,the node with the highest comprehensive degree in each core layer is selected as the seed.However,the seed selection strategy of KT can easily lose some influential nodes.Thus,by optimizing the seed selection strategy,this paper proposes an efficient heuristic algorithm called improved K-shell in temporal social networks for influence maximization(KTIM).According to the hierarchical distribution of cores,the algorithm adds nodes near the central core to the candidate seed set.It then searches for seeds in the candidate seed set according to the comprehensive degree.Experiments showthatKTIMis close to the best performing improved method for influence maximization of temporal graph(IMIT)algorithm in terms of effectiveness,but runs at least an order of magnitude faster than it.Therefore,considering the effectiveness and efficiency simultaneously in temporal social networks,the KTIM algorithm works better than other baseline algorithms. 展开更多
关键词 temporal social network influence maximization improved K-shell comprehensive degree
下载PDF
上一页 1 2 42 下一页 到第
使用帮助 返回顶部