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基于Temporal Fusion Transformer模型的变压器油中溶解气体预测方法
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作者 周延豪 范路 +3 位作者 任海龙 赵谡 王亚林 尹毅 《电力工程技术》 北大核心 2026年第3期37-45,56,共10页
油中溶解气体是评估变压器运行状态的重要指标,准确预测油中溶解气体的发展趋势有助于预防电力变压器故障。为解决传统预测模型中单一变量造成的预测效率低下,文中提出一种基于Optuna超参数优化的Temporal Fusion Transformer(TFT)模型... 油中溶解气体是评估变压器运行状态的重要指标,准确预测油中溶解气体的发展趋势有助于预防电力变压器故障。为解决传统预测模型中单一变量造成的预测效率低下,文中提出一种基于Optuna超参数优化的Temporal Fusion Transformer(TFT)模型。通过引入变压器组别、绕组相别、气体类别等静态变量以及可解释性的多头注意力机制,实现多组变压器油中溶解气体的同步预测,提升变电站运维系统的预警效率。相比于传统预测模型,文中模型预测的平均相对误差仅为0.306%,较Transformer模型降低了66.7%,且在短期和长期预测时均具有更高的预测准确度。此外,文中模型的训练时间仅为Transformer模型的1/4,更契合当前智能预警平台中多组别设备同步预测的发展趋势。模型中的多头注意力机制表明氢气和甲烷之间以及二氧化碳和甲烷之间具有强相关关系,其与油纸绝缘裂解的产气规律相一致,进一步表明文中模型具有良好的可解释性,可为多组别设备同步预测提供技术保障。 展开更多
关键词 电力变压器 油中溶解气体 同步预测 temporal Fusion Transformer(TFT)模型 时间序列 注意力机制
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Learning Time Embedding for Temporal Knowledge Graph Completion
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作者 Jinglu Chen Mengpan Chen +2 位作者 Wenhao Zhang Huihui Ren Daniel Dajun Zeng 《Computers, Materials & Continua》 2026年第2期827-851,共25页
Temporal knowledge graph completion(TKGC),which merges temporal information into traditional static knowledge graph completion(SKGC),has garnered increasing attention recently.Among numerous emerging approaches,transl... Temporal knowledge graph completion(TKGC),which merges temporal information into traditional static knowledge graph completion(SKGC),has garnered increasing attention recently.Among numerous emerging approaches,translation-based embedding models constitute a prominent approach in TKGC research.However,existing translation-based methods typically incorporate timestamps into entities or relations,rather than utilizing them independently.This practice fails to fully exploit the rich semantics inherent in temporal information,thereby weakening the expressive capability of models.To address this limitation,we propose embedding timestamps,like entities and relations,in one or more dedicated semantic spaces.After projecting all embeddings into a shared space,we use the relation-timestamp pair instead of the conventional relation embedding as the translation vector between head and tail entities.Our method elevates timestamps to the same representational significance as entities and relations.Based on this strategy,we introduce two novel translation-based embedding models:TE-TransR and TE-TransT.With the independent representation of timestamps,our method not only enhances capabilities in link prediction but also facilitates a relatively underexplored task,namely time prediction.To further bolster the precision and reliability of time prediction,we introduce a granular,time unit-based timestamp setting and a relation-specific evaluation protocol.Extensive experiments demonstrate that our models achieve strong performance on link prediction benchmarks,with TE-TransR outperforming existing baselines in the time prediction task. 展开更多
关键词 temporal knowledge graph(TKG) TKG embedding model link prediction time prediction
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Learning Temporal User Features for Repost Prediction with Large Language Models
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作者 Wu-Jiu Sun Xiao Fan Liu 《Computers, Materials & Continua》 2025年第3期4117-4136,共20页
Predicting information dissemination on social media,specifcally users’reposting behavior,is crucial for applications such as advertising campaigns.Conventional methods use deep neural networks to make predictions ba... Predicting information dissemination on social media,specifcally users’reposting behavior,is crucial for applications such as advertising campaigns.Conventional methods use deep neural networks to make predictions based on features related to user topic interests and social preferences.However,these models frequently fail to account for the difculties arising from limited training data and model size,which restrict their capacity to learn and capture the intricate patterns within microblogging data.To overcome this limitation,we introduce a novel model Adapt pre-trained Large Language model for Reposting Prediction(ALL-RP),which incorporates two key steps:(1)extracting features from post content and social interactions using a large language model with extensive parameters and trained on a vast corpus,and(2)performing semantic and temporal adaptation to transfer the large language model’s knowledge of natural language,vision,and graph structures to reposting prediction tasks.Specifcally,the temporal adapter in the ALL-RP model captures multi-dimensional temporal information from evolving patterns of user topic interests and social preferences,thereby providing a more realistic refection of user attributes.Additionally,to enhance the robustness of feature modeling,we introduce a variant of the temporal adapter that implements multiple temporal adaptations in parallel while maintaining structural simplicity.Experimental results on real-world datasets demonstrate that the ALL-RP model surpasses state-of-the-art models in predicting both individual user reposting behavior and group sharing behavior,with performance gains of 2.81%and 4.29%,respectively. 展开更多
关键词 Reposting prediction large language model semantic adaptation temporal adaptation
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STDNet:Improved lip reading via short-term temporal dependency modeling
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作者 Xiaoer WU Zhenhua TAN +1 位作者 Ziwei CHENG Yuran RU 《虚拟现实与智能硬件(中英文)》 2025年第2期173-187,共15页
Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of shor... Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of short-term temporal dependencies of lip-shape variations between adjacent frames,which leaves space for further improvement in feature extraction.Methods This article presents a spatiotemporal feature fusion network(STDNet)that compensates for the deficiencies of current lip-reading approaches in short-term temporal dependency modeling.Specifically,to distinguish more similar and intricate content,STDNet adds a temporal feature extraction branch based on a 3D-CNN,which enhances the learning of dynamic lip movements in adjacent frames while not affecting spatial feature extraction.In particular,we designed a local–temporal block,which aggregates interframe differences,strengthening the relationship between various local lip regions through multiscale convolution.We incorporated the squeeze-and-excitation mechanism into the Global-Temporal Block,which processes a single frame as an independent unitto learn temporal variations across the entire lip region more effectively.Furthermore,attention pooling was introduced to highlight meaningful frames containing key semantic information for the target word.Results Experimental results demonstrated STDNet's superior performance on the LRW and LRW-1000,achieving word-level recognition accuracies of 90.2% and 53.56%,respectively.Extensive ablation experiments verified the rationality and effectiveness of its modules.Conclusions The proposed model effectively addresses short-term temporal dependency limitations in lip reading,and improves the temporal robustness of the model against variable-length sequences.These advancements validate the importance of explicit short-term dynamics modeling for practical lip-reading systems. 展开更多
关键词 Lip reading Spatio-temporal feature fusion Short-term temporal dependency modeling
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Ultra-short-term Photovoltaic Power Prediction Based on Improved Temporal Convolutional Network and Feature Modeling
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作者 Hao Xiao Wanting Zheng +1 位作者 Hai Zhou Wei Pei 《CSEE Journal of Power and Energy Systems》 2025年第5期2024-2035,共12页
Accurate ultra-short-term photovoltaic(PV)power forecasting is crucial for mitigating variations caused by PV power generation and ensuring the stable and efficient operation of power grids.To capture intricate tempor... Accurate ultra-short-term photovoltaic(PV)power forecasting is crucial for mitigating variations caused by PV power generation and ensuring the stable and efficient operation of power grids.To capture intricate temporal relationships and enhance the precision of multi-step time forecast,this paper introduces an innovative approach for ultra-short-term photovoltaic(PV)power prediction,leveraging an enhanced Temporal Convolutional Neural Network(TCN)architecture and feature modeling.First,this study introduces a method employing the Spearman coefficient for meteorological feature filtration.Integrated with three-dimensional PV panel modeling,key factors influencing PV power generation are identified and prioritized.Second,the analysis of the correlation coefficient between astronomical features and PV power prediction demonstrates the theoretical substantiation for the practicality and essentiality of incorporating astronomical features.Third,an enhanced TCN model is introduced,augmenting the original TCN structure with a projection head layer to enhance its capacity for learning and expressing nonlinear features.Meanwhile,a new rolling timing network mechanism is constructed to guarantee the segmentation prediction of future long-time output sequences.Multiple experiments demonstrate the superior performance of the proposed forecasting method compared to existing models.The accuracy of PV power prediction in the next 4 hours,devoid of meteorological conditions,increases by 20.5%.Furthermore,incorporating shortwave radiation for predictions over 4 hours,2 hours,and 1 hour enhances accuracy by 11.1%,9.1%,and 8.8%,respectively. 展开更多
关键词 Astronomical feature feature modeling improved temporal convolutional neural network solar power generation ultra-short-term power generation prediction
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Integrating Temporal Change Detection and Advanced Hybrid Modeling to Predict Urban Expansion in Jaipur,a UNESCO World Heritage City
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作者 Saurabh Singh Sudip Pandey Ankush Kumar Jain 《Revue Internationale de Géomatique》 2025年第1期899-914,共16页
Urban expansion in semi-arid regions poses critical challenges for sustainable land management,ecological resilience,and heritage conservation.Jaipur,India-a United Nations Educational,Scientific and Cultural Organiza... Urban expansion in semi-arid regions poses critical challenges for sustainable land management,ecological resilience,and heritage conservation.Jaipur,India-a United Nations Educational,Scientific and Cultural Organization(UNESCO)World Heritage City located in a semi-arid environment-faces rapid urbanization that threatens agricultural productivity,fragile ecosystems,and cultural assets.This study quantifies past and projects future land use/land cover(LULC)dynamics in Jaipur to support evidence-based planning.Using theDynamicWorld dataset,we generated annual 10-m LULC maps from 2016 to 2025 within the municipal boundary.Temporal change detection was conducted through empirical transition probability analysis,and future scenarios for 2026-2030 were simulated with a Markov chain model coupled with a neighbour-aware cellular automata(CA-Markov)allocation to capture spatial diffusion and terrain constraints.Validation on a 2025 hold-out achieved an Overall Accuracy of 0.79,Cohen’sκof 0.15,and a figure of Merit of 0.073 for built-up gains,confirming credible localization of urban growth.Results reveal that the built-up area expanded from 340.57 km^(2) in 2016 to 387.25 km^(2) in 2025(+13.71%)and is projected to rise by+44.96%by 2030.Over 2016-2025,cropland declined by−40.83%,shrub/scrub by−27.71%,tree cover by−4.12%,and flooded vegetation by−41.28%,while bare ground(+3.14%),grass(−4.22%),and water(~+0.18%)showed minimal change.Forecasts for 2016-2030 indicate severe contractions in crops(−98.40%),shrub/scrub(−93.10%),trees(−80.44%),grass(−95.36%),water(−99.53%),bare ground(−99.51%),and flooded vegetation(−99.80%).These findings highlight an accelerating transformation of Jaipur’s peri-urban landscape,with built-up expansion occurring at the expense of nearly all productive and ecological land classes.The study demonstrates that CA-Markov-based LULC forecasting provides a reproducible and transparent framework for high-frequency monitoring and offers actionable insights for sustainable urban management in heritage cities under rapid growth pressure. 展开更多
关键词 Urban expansion land use/land cover(LULC) Markov chain modeling temporal change detection dynamic world remote sensing Jaipur landscape transformation URBANIZATION predictive mapping
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Completeness of bounded model checking temporal logic of knowledge 被引量:1
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作者 刘志锋 葛云 +1 位作者 章东 周从华 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期399-405,共7页
In order to find the completeness threshold which offers a practical method of making bounded model checking complete, the over-approximation for the complete threshold is presented. First, a linear logic of knowledge... In order to find the completeness threshold which offers a practical method of making bounded model checking complete, the over-approximation for the complete threshold is presented. First, a linear logic of knowledge is introduced into the past tense operator, and then a new temporal epistemic logic LTLKP is obtained, so that LTLKP can naturally and precisely describe the system's reliability. Secondly, a set of prior algorithms are designed to calculate the maximal reachable depth and the length of the longest of loop free paths in the structure based on the graph structure theory. Finally, some theorems are proposed to show how to approximate the complete threshold with the diameter and recurrence diameter. The proposed work resolves the completeness threshold problem so that the completeness of bounded model checking can be guaranteed. 展开更多
关键词 bounded model checking temporal logics of knowledge multi-agent system
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Temporal and spatial distribution characteristics of water resources in Guangdong Province based on a cloud model 被引量:9
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作者 Qi Zhou Wei Wang +2 位作者 Yong Pang Zhi-yong Zhou Hui-ping Luo 《Water Science and Engineering》 EI CAS CSCD 2015年第4期263-272,共10页
With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distr... With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distribution characteristics of water resources in Guangdong Province from 1956 to 2000 based on a cloud model. The spatial variation of the temporal distribution characteristics and the temporal variation of the spatial distribution characteristics were both analyzed. In addition, the relationships between the numerical characteristics of the cloud model of temporal and spatial distributions of water resources and precipitation were also studied. The results show that, using a cloud model, it is possible to intuitively describe the temporal and spatial distribution characteristics of water resources in cloud images. Water resources in Guangdong Province and their temporal and spatial distribution characteristics are differentiated by their geographic locations. Downstream and coastal areas have a larger amount of water resources with greater uniformity and stronger stability in terms of temporal distribution. Regions with more precipitation possess larger amounts of water resources, and years with more precipitation show greater nonuniformity in the spatial distribution of water resources. The correlation between the nonuniformity of the temporal distribution and local precipitation is small, and no correlation is found between the stability of the nonuniformity of the temporal and spatial distributions of water resources and precipitation. The amount of water resources in Guangdong Province shows an increasing trend from 1956 to 2000, the nonuniformity of the spatial distribution of water resources declines, and the stability of the nonuniformity of the spatial distribution of water resources is enhanced. 展开更多
关键词 Water resources temporal and spatial distribution characteristics Cloud model Guangdong Province
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Intrusion Detection Algorithm Based on Model Checking Interval Temporal Logic 被引量:5
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作者 朱维军 王忠勇 张海宾 《China Communications》 SCIE CSCD 2011年第3期66-72,共7页
Model checking based on linear temporal logic reduces the false negative rate of misuse detection.However,linear temporal logic formulae cannot be used to describe concurrent attacks and piecewise attacks.So there is ... Model checking based on linear temporal logic reduces the false negative rate of misuse detection.However,linear temporal logic formulae cannot be used to describe concurrent attacks and piecewise attacks.So there is still a high rate of false negatives in detecting these complex attack patterns.To solve this problem,we use interval temporal logic formulae to describe concurrent attacks and piecewise attacks.On this basis,we formalize a novel algorithm for intrusion detection based on model checking interval temporal logic.Compared with the method based on model checking linear temporal logic,the new algorithm can find unknown succinct attacks.The simulation results show that the new method can effectively reduce the false negative rate of concurrent attacks and piecewise attacks. 展开更多
关键词 network security intrusion detection misuse detection interval temporal logic model checking
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Spatio-temporal GIS Data Model Based on Event Semantics 被引量:5
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作者 XU Zhihong BIAN Fuling 《Geo-Spatial Information Science》 2003年第3期43-47,共5页
There are mainly four kinds of models to record and deal with historical information.By taking them as reference,the spatio-temporal model based on event semantics is proposed.In this model,according to the way for de... There are mainly four kinds of models to record and deal with historical information.By taking them as reference,the spatio-temporal model based on event semantics is proposed.In this model,according to the way for describing an event,all the information are divided into five domains.This paper describes the model by using the land parcel change in the cadastral information system,and expounds the model by using five tables corresponding to the five domains.With the aid of this model,seven examples are given on historical query,trace back and recurrence.This model can be implemented either in the extended relational database or in the object-oriented database. 展开更多
关键词 event semantics temporal GIS model
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Alternative Modalities for Temporal Bone Training in Otolaryngology:A Systematic Review 被引量:1
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作者 Quan Lu John Wenger Anita Jeyakumar 《Journal of Otology》 2025年第2期103-109,共7页
Objective:Critically appraise the current state of alternate temporal bone training techniques(virtual reality(VR)simulation,3D-printed models,and mental practice(MP))compared to traditional and cadaver methods.Databa... Objective:Critically appraise the current state of alternate temporal bone training techniques(virtual reality(VR)simulation,3D-printed models,and mental practice(MP))compared to traditional and cadaver methods.Databases Reviewed:PubMed,Cochrane,Web of Science.Methods:Search terms utilized“temporal bone training”,“temporal bone surgical modalities”,and“training modalities temporal bone surgery”with“3D”,“rapid prototyp*”,“stereolithography”,“additive manufact*”,“plaster”,“VR”,“virtual reality”,“animal model”,“animal temporal bone”,and“synthetic”with“AND”for all literature.Exclusion criteria:non-ENT,non-English,and did not compare against alternative/traditional methods.Results:10 studies were included with 322 participants(83.9%ENT residents and 16.1%medical students).Costs include the FDM printer($300),materials($5/3D model),and<$5,000 for freeware simulator hardware.The Welling scale was used in 50%of studies.Alternate methods produced comparable or improved assessment scores to traditional and cadaver methods.Injuries were reported in three VR studies,with two reported significantly lower injury scores in the intervention groups.Time to completion was not significantly different in four VR studies,except for one finding that the time to visualize the incus was significantly lower in the intervention group.Performance after MP was not statistically different.Conclusion:More data are needed to assess whether the alternate methods are comparable to cadaveric dissection in temporal bone training.3D models and VR simulation demonstrate promising potential for novel trainees to acquire the basic skills and produce performance comparable to or significantly better than traditional methods of lectures,textbooks,CT images,and operative videos. 展开更多
关键词 virtual reality virtual reality simulation 3D models CADAVER temporal bone training
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Exploration of spatial and temporal characteristics of PM2.5 concentration in Guangzhou, China using wavelet analysis and modified land use regression model 被引量:4
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作者 Fenglei Fan Runping Liu 《Geo-Spatial Information Science》 SCIE CSCD 2018年第4期311-321,共11页
This article attempts to detail time series characteristics of PM2.5 concentration in Guangzhou(China)from 1 June 2012 to 31 May 2013 based on wavelet analysis tools,and discuss its spatial distribution using geograph... This article attempts to detail time series characteristics of PM2.5 concentration in Guangzhou(China)from 1 June 2012 to 31 May 2013 based on wavelet analysis tools,and discuss its spatial distribution using geographic information system software and a modified land use regression model.In this modified model,an important variable(land use data)is substituted for impervious surface area,which can be obtained conveniently from remote sensing imagery through the linear spectral mixture analysis method.Impervious surface has higher precision than land use data because of its sub-pixel level.Seasonal concentration pattern and day-by-day change feature of PM2.5 in Guangzhou with a micro-perspective are discussed and understood.Results include:(1)the highest concentration of PM2.5 occurs in October and the lowest in July,respectively;(2)average concentration of PM2.5 in winter is higher than in other seasons;and(3)there are two high concentration zones in winter and one zone in spring. 展开更多
关键词 PM2.5 temporal change spatial distribution wavelet analysis land use regression(LUR)model GIS
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DEVELOPMENT OF A GIS DATA MODEL WITH SPATIAL,TEMPORAL AND ATTRIBUTE COMPONENTS BASED ON OBJECT-ORIENTED APPROACH 被引量:2
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作者 SHI Wenzhong ZHANG Minwen 《Geo-Spatial Information Science》 2000年第1期17-23,共7页
This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model ... This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model includes two major parts: (a) modeling the signal objects by STA-object elements, and (b) modeling relationships between STA-objects. As an example, the STA-model is applied for modeling land cover change data with spatial, temporal and attribute components. 展开更多
关键词 OBJECT-ORIENTATION GIS data modeling spatial temporal and attribute model
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ISDTM:An Intrusion Signatures Description Temporal Model 被引量:1
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作者 Ou Yang Ming-guang Zhou Yang-bo 《Wuhan University Journal of Natural Sciences》 CAS 2003年第02A期373-378,共6页
ISDTM,based on an augmented Allen's interval temporal logic(ITL)and first-order predicate calculus,is a formal temporal model for representing intrusion signatures.It is augmented with some real time extensions wh... ISDTM,based on an augmented Allen's interval temporal logic(ITL)and first-order predicate calculus,is a formal temporal model for representing intrusion signatures.It is augmented with some real time extensions which enhance the expressivity.Intrusion scenarios usually are the set of events and system states,where-the temporal sequence is their basic relation.Intrusion signatures description,therefore,is to represent such temporal relations in a sense.While representing these signatures,ISDTM decomposes the intrusion process into the sequence of events according to their relevant intervals,and then specifies network states in these Intervals.The uncertain intrusion signatures as well as basic temporal modes of events,which consist of the parallel mode,the sequential mode and the hybrid mode,can be succinctly and naturally represented in ISDTM.Mode chart is the visualization of intrusion signatures in ISDTM,which makes the formulas more readable.The intrusion signatures descriptions in ISDTM have advantages of compact construct,concise syntax,scalability and easy implementation. 展开更多
关键词 ISDTM uncertain intrusion signatures intru-sion detection temporal model
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Ensemble Based Temporal Weighting and Pareto Ranking (ETP) Model for Effective Root Cause Analysis 被引量:1
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作者 Naveen Kumar Seerangan S.Vijayaragavan Shanmugam 《Computers, Materials & Continua》 SCIE EI 2021年第10期819-830,共12页
Root-cause identification plays a vital role in business decision making by providing effective future directions for the organizations.Aspect extraction and sentiment extraction plays a vital role in identifying the ... Root-cause identification plays a vital role in business decision making by providing effective future directions for the organizations.Aspect extraction and sentiment extraction plays a vital role in identifying the rootcauses.This paper proposes the Ensemble based temporal weighting and pareto ranking(ETP)model for Root-cause identification.Aspect extraction is performed based on rules and is followed by opinion identification using the proposed boosted ensemble model.The obtained aspects are validated and ranked using the proposed aspect weighing scheme.Pareto-rule based aspect selection is performed as the final selection mechanism and the results are presented for business decision making.Experiments were performed with the standard five product benchmark dataset.Performances on all five product reviews indicate the effective performance of the proposed model.Comparisons are performed using three standard state-of-the-art models and effectiveness is measured in terms of F-Measure and Detection rates.The results indicate improved performances exhibited by the proposed model with an increase in F-Measure levels at 1%–15%and detection rates at 4%–24%compared to the state-of-the-art models. 展开更多
关键词 Root cause analysis sentiment analysis aspect extraction ensemble modelling temporal weighting pareto ranking
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A Methodology for Estimating Leaf Area Index by Assimilating Remote Sensing Data into Crop Model Based on Temporal and Spatial Knowledge 被引量:1
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作者 ZHU Xiaohua ZHAO Yingshi FENG Xiaoming 《Chinese Geographical Science》 SCIE CSCD 2013年第5期550-561,共12页
In this paper,a methodology for Leaf Area Index(LAI) estimating was proposed by assimilating remote sensed data into crop model based on temporal and spatial knowledge.Firstly,sensitive parameters of crop model were c... In this paper,a methodology for Leaf Area Index(LAI) estimating was proposed by assimilating remote sensed data into crop model based on temporal and spatial knowledge.Firstly,sensitive parameters of crop model were calibrated by Shuffled Complex Evolution method developed at the University of Arizona(SCE-UA) optimization method based on phenological information,which is called temporal knowledge.The calibrated crop model will be used as the forecast operator.Then,the Taylor′s mean value theorem was applied to extracting spatial information from the Moderate Resolution Imaging Spectroradiometer(MODIS) multi-scale data,which was used to calibrate the LAI inversion results by A two-layer Canopy Reflectance Model(ACRM) model.The calibrated LAI result was used as the observation operator.Finally,an Ensemble Kalman Filter(EnKF) was used to assimilate MODIS data into crop model.The results showed that the method could significantly improve the estimation accuracy of LAI and the simulated curves of LAI more conform to the crop growth situation closely comparing with MODIS LAI products.The root mean square error(RMSE) of LAI calculated by assimilation is 0.9185 which is reduced by 58.7% compared with that by simulation(0.3795),and before and after assimilation the mean error is reduced by 92.6% which is from 0.3563 to 0.0265.All these experiments indicated that the methodology proposed in this paper is reasonable and accurate for estimating crop LAI. 展开更多
关键词 ASSIMILATION temporal and spatial knowledge Leaf Area Index (LAI) crop model Ensemble Kalman Filter (EnKF)
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WHU-Grace01s:A new temporal gravity field model recovered from GRACE KBRR data alone 被引量:3
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作者 Zhou Hao Luo Zhicai Zhong Bo 《Geodesy and Geodynamics》 2015年第5期316-323,共8页
A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment (GRACE) K-Band Range Rate (KBRR) data based on dynamic integral approach is presented in this pa... A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment (GRACE) K-Band Range Rate (KBRR) data based on dynamic integral approach is presented in this paper. After meticulously preprocessing of the GRACE KBRR data, the root mean square of its post residuals is about 0.2 micrometers per second, and seventy-two monthly temporal solutions truncated to degree and order 60 are computed for the period from January 2003 to December 2008. After applying the combi- nation filter in WHU-Grace01s, the global temporal signals show obvious periodical change rules in the large-scale fiver basins. In terms of the degree variance, our solution is smaller at high degrees, and shows a good consistency at the rest of degrees with the Release 05 models from Center for Space Research (CSR), GeoForschungsZentrum Potsdam (GFZ) and Jet Pro- pulsion Laboratory 0PL). Compared with other published models in terms of equivalent water height distribution, our solution is consistent with those published by CSR, GFZ, JPL, Delft institute of Earth Observation and Space system (DEOS), Tongji University (Tongji), Institute of Theoretical Geodesy (ITG), Astronomical Institute in University of Bern (AIUB) and Groupe de Recherche de Geodesie Spatiale (GRGS}, which indicates that the accuracy of WHU-Grace01s has a good consistency with the previously published GRACE solutions. 展开更多
关键词 temporal gravity field model Gravity Recovery and Climate Experiment (GRACE) Dynamic integral approach K-Band Range Rate (KBRR) Satellite gravity Spherical harmonics Equivalent water height Geopotential determination
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Effect of Spatial and Temporal Scales on Habitat Suitability Modeling:A Case Study of Ommastrephes bartramii in the Northwest Pacific Ocean 被引量:2
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作者 GONG Caixia CHEN Xinjun +1 位作者 GAO Feng TIAN Siquan 《Journal of Ocean University of China》 SCIE CAS 2014年第6期1043-1053,共11页
Temporal and spatial scales play important roles in fishery ecology,and an inappropriate spatio-temporal scale may result in large errors in modeling fish distribution.The objective of this study is to evaluate the ro... Temporal and spatial scales play important roles in fishery ecology,and an inappropriate spatio-temporal scale may result in large errors in modeling fish distribution.The objective of this study is to evaluate the roles of spatio-temporal scales in habitat suitability modeling,with the western stock of winter-spring cohort of neon flying squid (Ornmastrephes bartramii) in the northwest Pacific Ocean as an example.In this study,the fishery-dependent data from the Chinese Mainland Squid Jigging Technical Group and sea surface temperature (SST) from remote sensing during August to October of 2003-2008 were used.We evaluated the differences in a habitat suitability index model resulting from aggregating data with 36 different spatial scales with a combination of three latitude scales (0.5°,1 ° and 2°),four longitude scales (0.5°,1°,2° and 4°),and three temporal scales (week,fortnight,and month).The coefficients of variation (CV) of the weekly,biweekly and monthly suitability index (SI) were compared to determine which temporal and spatial scales of SI model are more precise.This study shows that the optimal temporal and spatial scales with the lowest CV are month,and 0.5° latitude and 0.5° longitude for O.bartramii in the northwest Pacific Ocean.This suitability index model developed with an optimal scale can be cost-effective in improving forecasting fishing ground and requires no excessive sampling efforts.We suggest that the uncertainty associated with spatial and temporal scales used in data aggregations needs to be considered in habitat suitability modeling. 展开更多
关键词 spatial and temporal scales data aggregation habitat suitability model sea surface temperature Ommastrephes bartramii northwest Pacific Ocean
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Spatio-temporal dynamics of maize cropping system in Northeast China between 1980 and 2010 by using spatial production allocation model 被引量:12
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作者 TAN Jieyang YANG Peng +6 位作者 LIU Zhenhuan WU Wenbin ZHANG Li LI Zhipeng YOU Liangzhi TANG Huajun LI Zhengguo 《Journal of Geographical Sciences》 SCIE CSCD 2014年第3期397-410,共14页
Understanding crop patterns and their changes on regional scale is a critical re- quirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are st... Understanding crop patterns and their changes on regional scale is a critical re- quirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are still lacking. Based on the cross-entropy theory, a spatial production allocation model (SPAM) has been developed for presenting spa- tio-temporal dynamics of maize cropping system in Northeast China during 1980-2010. The simulated results indicated that (1) maize sown area expanded northwards to 48~N before 2000, after that the increased sown area mainly occurred in the central and southern parts of Northeast China. Meanwhile, maize also expanded eastwards to 127°E and lower elevation (less than 100 m) as well as higher elevation (mainly distributed between 200 m and 350 m); (2) maize yield has been greatly promoted for most planted area of Northeast China, espe- cially in the planted zone between 42°N and 48°N, while the yield increase was relatively homogeneous without obvious longitudinal variations for whole region; (3) maize planting density increased gradually to a moderately high level over the investigated period, which reflected the trend of aggregation of maize cultivation driven by market demand. 展开更多
关键词 spring maize spatial production allocation model spatio-temporal pattern Northeast China
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Convolutional BiLSTM Variational Sequence-To-Sequence Based Video Captioning for Capturing Intricate Temporal Dependencies
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作者 M.Gowri Shankar D.Surendran 《Journal of Bionic Engineering》 2025年第5期2700-2716,共17页
In the realm of video understanding,the demand for accurate and contextually rich video captioning has surged with the increasing volume and complexity of multimedia content.This research introduces an innovative solu... In the realm of video understanding,the demand for accurate and contextually rich video captioning has surged with the increasing volume and complexity of multimedia content.This research introduces an innovative solution for video captioning by integrating a Convolutional BiLSTM Convolutional Bidirectional Long Short-Term Memory(BiLSTM)constructed Variational Sequence-to-Sequence(CBVSS)approach.The proposed framework is adept at capturing intricate temporal dependencies within video sequences,enabling a more nuanced and contextually relevant description of dynamic scenes.However,optimizing its parameters for improved performance remains a crucial challenge.In response,in this research Golden Eagle Optimization(GEO)a metaheuristic optimization technique is used to fine-tune the Convolutional BiLSTM variational sequence-to-sequence model parameters.The application of GEO aims to enhancing the CBVSS ability to produce more exact and contextually rich video captions.The proposed attains an overall higher Recall of 59.75%and Precision of 63.78%for both datasets.Additionally,the proposed CBVSS method demonstrated superior performance across both datasets,achieving the highest METEOR(25.67)and CIDER(39.87)scores on the ActivityNet dataset,and further outperforming all compared models on the YouCook2 dataset with METEOR(28.67)and CIDER(43.02),highlighting its effectiveness in generating semantically rich and contextually accurate video captions. 展开更多
关键词 Video captioning Convolutional BiLSTM Variational sequence-to-sequence model Golden eagleoptimization Intricate temporal dependencies
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