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Investigation on Damage Regularity of Mikania micrantha
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作者 Shaojian MA Yanling LUO Ju YANG 《Plant Diseases and Pests》 2024年第2期17-18,21,共3页
[Objectives]The paper was to understand the occurrence and damage regularity of the invasive plant Mikania micrantha in Huadu District of Guangzhou.[Methods]The damage status of M.micranthFa in different forest lands ... [Objectives]The paper was to understand the occurrence and damage regularity of the invasive plant Mikania micrantha in Huadu District of Guangzhou.[Methods]The damage status of M.micranthFa in different forest lands and its annual growth dynamics were investigated by field investigation.[Results]With the change of canopy density from low to high,the occurrence degree of M.micrantha changed from high to low.The occurrence degree of M.micrantha in different forest land types was:abandoned orchard>wasteland>roadside greenbelt>waterside>forest edge>normally managed orchard.[Conclusions]M.micrantha enters the rapid growth period from March to May in spring,with the growth rate gradually slowing down after June.The result provides a theoretical basis and practical guidance for the prevention and control of M.micrantha. 展开更多
关键词 Mikania micrantha regularity of outbreak Coverage survey Monitoring PREVENTION
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Low-Rank Multi-View Subspace Clustering Based on Sparse Regularization
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作者 Yan Sun Fanlong Zhang 《Journal of Computer and Communications》 2024年第4期14-30,共17页
Multi-view Subspace Clustering (MVSC) emerges as an advanced clustering method, designed to integrate diverse views to uncover a common subspace, enhancing the accuracy and robustness of clustering results. The signif... Multi-view Subspace Clustering (MVSC) emerges as an advanced clustering method, designed to integrate diverse views to uncover a common subspace, enhancing the accuracy and robustness of clustering results. The significance of low-rank prior in MVSC is emphasized, highlighting its role in capturing the global data structure across views for improved performance. However, it faces challenges with outlier sensitivity due to its reliance on the Frobenius norm for error measurement. Addressing this, our paper proposes a Low-Rank Multi-view Subspace Clustering Based on Sparse Regularization (LMVSC- Sparse) approach. Sparse regularization helps in selecting the most relevant features or views for clustering while ignoring irrelevant or noisy ones. This leads to a more efficient and effective representation of the data, improving the clustering accuracy and robustness, especially in the presence of outliers or noisy data. By incorporating sparse regularization, LMVSC-Sparse can effectively handle outlier sensitivity, which is a common challenge in traditional MVSC methods relying solely on low-rank priors. Then Alternating Direction Method of Multipliers (ADMM) algorithm is employed to solve the proposed optimization problems. Our comprehensive experiments demonstrate the efficiency and effectiveness of LMVSC-Sparse, offering a robust alternative to traditional MVSC methods. 展开更多
关键词 CLUSTERinG Multi-View Subspace Clustering Low-Rank Prior Sparse regularization
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A New Result on Regular Designs under Baseline Parameterization
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作者 Mengru Qin Yuna Zhao 《Open Journal of Applied Sciences》 2024年第2期441-449,共9页
The study on designs for the baseline parameterization has aroused attention in recent years. This paper focuses on two-level regular designs for the baseline parameterization. A general result on the relationship bet... The study on designs for the baseline parameterization has aroused attention in recent years. This paper focuses on two-level regular designs for the baseline parameterization. A general result on the relationship between K-aberration and word length pattern is developed. 展开更多
关键词 Baseline Parameterization K-Aberration regular Design Word Length Pattern
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Regularization by Multiple Dual Frames for Compressed Sensing Magnetic Resonance Imaging With Convergence Analysis 被引量:1
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作者 Baoshun Shi Kexun Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2136-2153,共18页
Plug-and-play priors are popular for solving illposed imaging inverse problems. Recent efforts indicate that the convergence guarantee of the imaging algorithms using plug-andplay priors relies on the assumption of bo... Plug-and-play priors are popular for solving illposed imaging inverse problems. Recent efforts indicate that the convergence guarantee of the imaging algorithms using plug-andplay priors relies on the assumption of bounded denoisers. However, the bounded properties of existing plugged Gaussian denoisers have not been proven explicitly. To bridge this gap, we detail a novel provable bounded denoiser termed as BMDual,which combines a trainable denoiser using dual tight frames and the well-known block-matching and 3D filtering(BM3D)denoiser. We incorporate multiple dual frames utilized by BMDual into a novel regularization model induced by a solver. The proposed regularization model is utilized for compressed sensing magnetic resonance imaging(CSMRI). We theoretically show the bound of the BMDual denoiser, the bounded gradient of the CSMRI data-fidelity function, and further demonstrate that the proposed CSMRI algorithm converges. Experimental results also demonstrate that the proposed algorithm has a good convergence behavior, and show the effectiveness of the proposed algorithm. 展开更多
关键词 Bounded denoiser compressed sensing magnetic resonance imaging(CSMRI) dual frames plug-and-play priors regularIZATION
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Outline of Uranium Resources Characteristics and Metallogenetic Regularity in China 被引量:12
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作者 CAI Yuqi ZHANG Jindai +6 位作者 LI Ziying GUO Qingyin SONG Jiye FAN Honghai LIU Wusheng QI Fucheng ZHANG Minglin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期918-937,共20页
Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.Dur... Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.During the implementation of this project,the authors summarized the metallogenic regularity of uranium resource in China systematically,through the researches of geological characteristics of uranium resource,uranium deposits type(genetic and prediction type),temporal and spatial distribution,and metallogenic series.Based on the investigation of present situation and progress in uranium exploration,this paper proposes the uranium deposits in China should be divided into 4 classes,9 types,21 subtypes in genetic,and 50 types in prediction;suggests to divide China into 29 uranium metallogenic belts and 20 uranium prospective area,and constructs 20uranium-polymetallic metallogenic series,through summarizing temporal and spatial distribution characteristics and metallogenic regularity of uranium deposits in China.The above research is beneficial to the comprehensive understanding of regional uranium metallogenic regularity,and will direct the uranium exploration in the future. 展开更多
关键词 Uranium deposit uranium deposit type uranium metallogenic regularity uraniummetallogenic belt uranium metallogenic series
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GLOBAL REGULARITY OF 2D INCOMPRESSIBLE MAGNETO-MICROPOLAR FLUID EQUATIONS WITH PARTIAL VISCOSITY
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作者 林红霞 刘森 +1 位作者 张恒 白茹 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1275-1300,共26页
This paper studies the global regularity of 2D incompressible anisotropic magnetomicropolar fluid equations with partial viscosity. Ma [22](Ma L. Nonlinear Anal: Real World Appl, 2018, 40: 95–129) examined the global... This paper studies the global regularity of 2D incompressible anisotropic magnetomicropolar fluid equations with partial viscosity. Ma [22](Ma L. Nonlinear Anal: Real World Appl, 2018, 40: 95–129) examined the global regularity of the 2D incompressible magnetomicropolar fluid system for 21 anisotropic partial viscosity cases. He proved the global existence of a classical solution for some cases and established the conditional global regularity for some other cases. In this paper, we also investigate the global regularity of 12 cases in [22]and some other new partial viscosity cases. The global regularity is established by providing new regular conditions. Our work improves some results in [22] in this sense of weaker regular criteria. 展开更多
关键词 magneto-micropolar fluid equations partial dissipation global regularity regular criteria
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Entropy of Regular Black Holes in Einstein's Gravity
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作者 兰晨 缪炎刚 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第12期13-18,共6页
We calculate the entropy of spherically symmetric regular black holes by the path-integral method in Einstein's gravity. This method provides evidence that the entropy of spherically symmetric regular black holes ... We calculate the entropy of spherically symmetric regular black holes by the path-integral method in Einstein's gravity. This method provides evidence that the entropy of spherically symmetric regular black holes is proportional to a quarter of horizon area, indicating no violation of the entropy-area law. 展开更多
关键词 ENTROPY EinSTEin regular
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THE REGULARITY AND UNIQUENESS OF A GLOBAL SOLUTION TO THE ISENTROPIC NAVIER-STOKES EQUATION WITH ROUGH INITIAL DATA
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作者 王海涛 张雄韬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1675-1716,共42页
A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and ... A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and regularity of the constructed solution.The key ingredients are the Holder continuity estimates of the heat kernel in both spatial and time variables.With these finer estimates,we obtain higher order regularity of the constructed solution to Navier-Stokes equation,so that all of the derivatives in the equation of conservative form are in the strong sense.Moreover,this regularity also allows us to identify a function space such that the stability of the solutions can be established there,which eventually implies the uniqueness. 展开更多
关键词 compressible Navier-Stokes equation BV initial data regularITY UNIQUENESS
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THE REGULARITY CRITERIA OF WEAK SOLUTIONS TO 3D AXISYMMETRIC INCOMPRESSIBLE BOUSSINESQ EQUATIONS
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作者 董玉 黄耀芳 +1 位作者 李莉 卢青 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2387-2397,共11页
In this paper,we obtain new regularity criteria for the weak solutions to the three dimensional axisymmetric incompressible Boussinesq equations.To be more precise,under some conditions on the swirling component of vo... In this paper,we obtain new regularity criteria for the weak solutions to the three dimensional axisymmetric incompressible Boussinesq equations.To be more precise,under some conditions on the swirling component of vorticity,we can conclude that the weak solutions are regular. 展开更多
关键词 Boussinesq equations regularity criteria AXISYMMETRY
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Ground fissure development regularity and formation mechanism of shallow buried coal seam mining with Karst landform in Jiaozi coal mine: a case study
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作者 ZHU Heng-zhong 《Journal of Mountain Science》 SCIE CSCD 2023年第10期3101-3120,共20页
A comprehensive study was undertaken at Jiaozi coal mine to investigate the development regularity of ground fissures in shallow buried coal seam mining with Karst landform,shedding light on the development type,geogr... A comprehensive study was undertaken at Jiaozi coal mine to investigate the development regularity of ground fissures in shallow buried coal seam mining with Karst landform,shedding light on the development type,geographical distribution,dynamic development process,and failure mechanism of these ground fissures by employing field monitoring,numerical simulation,and theoretical analysis.The findings demonstrate that ground fissure development has an obvious feature of subregion,and its geographical distribution is significantly affected by topography.Tensile type,open type,and stepped type are three different categories of ground fissure.Ground fissures emerge dynamically as the panel advances,and they typically develop with a distance of less than periodic weighting step distance in advance of panel advancing position.Ground fissures present the dynamic development feature,temporary fissure has the ability of self-healing.The dynamic development process of ground fissure with closed-distance coal seam repeated mining is expounded,and the development scale is a dynamic development stage of“closure→expansion→stabilized”on the basis of the original development scale.From the perspective of topsoil deformation,the computation model considering two points movement vectors towards two directions of the gob and the ground surface is established,the development criterion considering the critical deformation value of topsoil is obtained.The mechanical model of hinged structure of inclined body is proposed to clarify the ground fissure development,and the interaction between slope activity and ground fissure development is expounded.These research results fulfill the gap of ground fissures about development regularity and formation mechanism,and can contribute to ground fissure prevention and treatment with Karst landform. 展开更多
关键词 Karst landform Shallow buried coal seam Development regularity Formation mechanism Ground fissure Repeated mining
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Air combat target maneuver trajectory prediction based on robust regularized Volterra series and adaptive ensemble online transfer learning
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作者 Xi Zhi-fei Kou Ying-xin +4 位作者 Li Zhan-wu Lv Yue Xu An Li You Li Shuang-qing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期187-206,共20页
Target maneuver trajectory prediction is an important prerequisite for air combat situation awareness and maneuver decision-making.However,how to use a large amount of trajectory data generated by air combat confronta... Target maneuver trajectory prediction is an important prerequisite for air combat situation awareness and maneuver decision-making.However,how to use a large amount of trajectory data generated by air combat confrontation training to achieve real-time and accurate prediction of target maneuver trajectory is an urgent problem to be solved.To solve this problem,in this paper,a hybrid algorithm based on transfer learning,online learning,ensemble learning,regularization technology,target maneuvering segmentation point recognition algorithm,and Volterra series,abbreviated as AERTrOS-Volterra is proposed.Firstly,the model makes full use of a large number of trajectory sample data generated by air combat confrontation training,and constructs a Tr-Volterra algorithm framework suitable for air combat target maneuver trajectory prediction,which realizes the extraction of effective information from the historical trajectory data.Secondly,in order to improve the real-time online prediction accuracy and robustness of the prediction model in complex electromagnetic environments,on the basis of the TrVolterra algorithm framework,a robust regularized online Sequential Volterra prediction model is proposed by integrating online learning method,regularization technology and inverse weighting calculation method based on the priori error.Finally,inspired by the preferable performance of models ensemble,ensemble learning scheme is also incorporated into our proposed algorithm,which adaptively updates the ensemble prediction model according to the performance of the model on real-time samples and the recognition results of target maneuvering segmentation points,including the adaptation of model weights;adaptation of parameters;and dynamic inclusion and removal of models.Compared with many existing time series prediction methods,the newly proposed target maneuver trajectory prediction algorithm can fully mine the prior knowledge contained in the historical data to assist the current prediction.The rationality and effectiveness of the proposed algorithm are verified by simulation on three sets of chaotic time series data sets and a set of real target maneuver trajectory data sets. 展开更多
关键词 Maneuver trajectory prediction Volterra series Transfer learning Online learning Ensemble learning Robust regularization
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Experimental observation on water entry of a sphere in regular wave
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作者 Qian Wang Changze Zhao +1 位作者 Haocheng Lu Hua Liu 《Theoretical & Applied Mechanics Letters》 CSCD 2023年第5期367-374,共8页
This paper presents a novel experiment to observe the whole water entry process of a free-falling sphere into a regular wave.A time-accurate synchronizing system modulates the moment elaborately to ensure the sphere i... This paper presents a novel experiment to observe the whole water entry process of a free-falling sphere into a regular wave.A time-accurate synchronizing system modulates the moment elaborately to ensure the sphere impacting onto the water surface at the desirable wave phase.Four high-speed cameras focus locally to measure the high-precision size of the cavity evolution.Meanwhile,the aggregated field view of the camera array covers both the splash above the free surface and the entire cavity in the wave.The detailed methodologies are described and verified for the hardware set-up and the image post-processing.The theoretical maximum deviation is 1.7%on the space scale.The integral morphology of the cavity is captured precisely in the coordinate system during the sphere penetrates through the water at four representative wave phases and the still water.The result shows that the horizontal velocity of the fluid particle in the wave impels the cavity and changes the shape distinctly.Notably,the wave motion causes the cavity to pinch offearlier at the wave trough phase and later at the wave crest phase than in the still water.The wave motion influences the falling process of the sphere slightly in the present parameters. 展开更多
关键词 Physical experiment Water entry Free-falling sphere regular wave
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Regularity classification and corresponding analysis method requirements of horizontally curved bridges with unequal pier heights
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作者 Mohammad Jalal Maleki-amin Shahrokh Maalek 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第2期549-571,共23页
The seismic behavior of horizontally curved bridges,particularly with unequal height piers,is more complicated than that of straight bridges due to their geometric properties.In this study,the seismic responses of sev... The seismic behavior of horizontally curved bridges,particularly with unequal height piers,is more complicated than that of straight bridges due to their geometric properties.In this study,the seismic responses of several horizontally curved single-column-bent viaducts with various degrees of curvature and different pier heights have been investigated,employing three different analysis approaches:namely,modal pushover analysis,uniform load method,and nonlinear time history analysis.Considering the investigated bridge configurations and utilizing the most common regularity indices,the results indicate that viaducts with 45-degree and 90-degree deck subtended angles can be categorized as regular and moderately irregular,respectively,while the bridges with 180-degree deck subtended angle are found to be highly irregular.Furthermore,the viaducts whose pier heights are asymmetric may be considered as irregular for almost all ranges of the deck subtended angles.The effects of higher transverse and longitudinal modes are discussed and the minimum analysis requirements are identified to assess the seismic response of such bridge configurations for design purposes.Although the Regularity Indices used here are useful tools to distinguish between regular and irregular bridges,further studies are needed to improve their reliability. 展开更多
关键词 horizontally curved bridges unequal height piers pushover analysis regularity index seismic analysis and response
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Regularised Layerwise Weight Norm Based Skin Lesion Features Extraction and Classification
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作者 S.Gopikha M.Balamurugan 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2727-2742,共16页
Melanoma is the most lethal malignant tumour,and its prevalence is increasing.Early detection and diagnosis of skin cancer can alert patients to manage precautions and dramatically improve the lives of people.Recently... Melanoma is the most lethal malignant tumour,and its prevalence is increasing.Early detection and diagnosis of skin cancer can alert patients to manage precautions and dramatically improve the lives of people.Recently,deep learning has grown increasingly popular in the extraction and categorization of skin cancer features for effective prediction.A deep learning model learns and co-adapts representations and features from training data to the point where it fails to perform well on test data.As a result,overfitting and poor performance occur.To deal with this issue,we proposed a novel Consecutive Layerwise weight Con-straint MaxNorm model(CLCM-net)for constraining the norm of the weight vector that is scaled each time and bounding to a limit.This method uses deep convolutional neural networks and also custom layer-wise weight constraints that are set to the whole weight matrix directly to learn features efficiently.In this research,a detailed analysis of these weight norms is performed on two distinct datasets,International Skin Imaging Collaboration(ISIC)of 2018 and 2019,which are challenging for convolutional networks to handle.According to thefindings of this work,CLCM-net did a better job of raising the model’s performance by learning the features efficiently within the size limit of weights with appropriate weight constraint settings.The results proved that the proposed techniques achieved 94.42%accuracy on ISIC 2018,91.73%accuracy on ISIC 2019 datasets and 93%of accuracy on combined dataset. 展开更多
关键词 NORM OVERFITTinG regularIZATION MELANOMA weight constraints
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Types of uranium deposits in central Zhuguang Mountains in Hunan Province,South China and their metallogenic regularity and prospecting directions 被引量:8
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作者 Zhen-hua Xiao Shen-bang Xiong +4 位作者 Chun-hua Li Ying Liu Zhong-ding Yang Xiao-xi Feng Xue-wen Liu 《China Geology》 2020年第3期411-424,共14页
The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in th... The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in this area are all granite-related and they can be divided into three types,namely endogranitic ones,perigranitic ones,and contact zone types.The endogranitic uranium deposits are mainly controlled by the structural alteration zones developing within granites,with fragmentation,hematitization,and alkali metasomatism as their main mineralization characteristics.The perigranitic uranium deposits are mainly produced in the carbonaceous,siliceous,and argillaceous composite layers of epimetamorphic rocks and are controlled by fractured zones formed due to interlayer compression.The contact zone type uranium deposits mainly occur in the contact parts between the granites and favorable horizons.They have developed in favorable sections where multiple sets of structures are combined and intersected.The main metallogenic regularities of uranium in the central Zhuguang Mountains are as follows.The basic conditions for the uranium mineralization in this area include the framework consisting of regional deep large faults and their associated multi-set multi-direction favorable metallogenic structures,multi-cycle and multi-stage uranium-rich rock masses,and uranium-rich folded basement.Meanwhile,the uranium deposits in this area are closely related to granites in terms of genesis and space and they are formed in different structural parts subject to the same metallization.Furthermore,based on the summary of the characteristics and regularities of uranium mineralization in this area,the controlling factors of different types of uranium deposits in the area were explored and six metallogenic target areas were predicted.All these will provide references for the exploration of uranium deposits in this area. 展开更多
关键词 Uranium deposits Magmatic hydrothermal type Metallogenic regularity Mineral exploration engineering Prospecting direction Zhuguang Mountain Hunan Province South China
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Neural Machine Translation Models with Attention-Based Dropout Layer
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作者 Huma Israr Safdar Abbas Khan +3 位作者 Muhammad Ali Tahir Muhammad Khuram Shahzad Muneer Ahmad Jasni Mohamad Zain 《Computers, Materials & Continua》 SCIE EI 2023年第5期2981-3009,共29页
In bilingual translation,attention-based Neural Machine Translation(NMT)models are used to achieve synchrony between input and output sequences and the notion of alignment.NMT model has obtained state-of-the-art perfo... In bilingual translation,attention-based Neural Machine Translation(NMT)models are used to achieve synchrony between input and output sequences and the notion of alignment.NMT model has obtained state-of-the-art performance for several language pairs.However,there has been little work exploring useful architectures for Urdu-to-English machine translation.We conducted extensive Urdu-to-English translation experiments using Long short-term memory(LSTM)/Bidirectional recurrent neural networks(Bi-RNN)/Statistical recurrent unit(SRU)/Gated recurrent unit(GRU)/Convolutional neural network(CNN)and Transformer.Experimental results show that Bi-RNN and LSTM with attention mechanism trained iteratively,with a scalable data set,make precise predictions on unseen data.The trained models yielded competitive results by achieving 62.6%and 61%accuracy and 49.67 and 47.14 BLEU scores,respectively.From a qualitative perspective,the translation of the test sets was examined manually,and it was observed that trained models tend to produce repetitive output more frequently.The attention score produced by Bi-RNN and LSTM produced clear alignment,while GRU showed incorrect translation for words,poor alignment and lack of a clear structure.Therefore,we considered refining the attention-based models by defining an additional attention-based dropout layer.Attention dropout fixes alignment errors and minimizes translation errors at the word level.After empirical demonstration and comparison with their counterparts,we found improvement in the quality of the resulting translation system and a decrease in the perplexity and over-translation score.The ability of the proposed model was evaluated using Arabic-English and Persian-English datasets as well.We empirically concluded that adding an attention-based dropout layer helps improve GRU,SRU,and Transformer translation and is considerably more efficient in translation quality and speed. 展开更多
关键词 Natural language processing neural machine translation word embedding ATTENTION PERPLEXITY selective dropout regularization URDU PERSIAN Arabic BLEU
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Brain Functional Networks with Dynamic Hypergraph Manifold Regularization for Classification of End-Stage Renal Disease Associated with Mild Cognitive Impairment
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作者 Zhengtao Xi Chaofan Song +2 位作者 Jiahui Zheng Haifeng Shi Zhuqing Jiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2243-2266,共24页
The structure and function of brain networks have been altered in patients with end-stage renal disease(ESRD).Manifold regularization(MR)only considers the pairing relationship between two brain regions and cannot rep... The structure and function of brain networks have been altered in patients with end-stage renal disease(ESRD).Manifold regularization(MR)only considers the pairing relationship between two brain regions and cannot represent functional interactions or higher-order relationships between multiple brain regions.To solve this issue,we developed a method to construct a dynamic brain functional network(DBFN)based on dynamic hypergraph MR(DHMR)and applied it to the classification of ESRD associated with mild cognitive impairment(ESRDaMCI).The construction of DBFN with Pearson’s correlation(PC)was transformed into an optimization model.Node convolution and hyperedge convolution superposition were adopted to dynamically modify the hypergraph structure,and then got the dynamic hypergraph to form the manifold regular terms of the dynamic hypergraph.The DHMR and L_(1) norm regularization were introduced into the PC-based optimization model to obtain the final DHMR-based DBFN(DDBFN).Experiment results demonstrated the validity of the DDBFN method by comparing the classification results with several related brain functional network construction methods.Our work not only improves better classification performance but also reveals the discriminative regions of ESRDaMCI,providing a reference for clinical research and auxiliary diagnosis of concomitant cognitive impairments. 展开更多
关键词 End-stage renal disease mild cognitive impairment brain functional network dynamic hypergraph manifold regularization CLASSIFICATION
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Coalbed Methane Enrichment Regularity and Major Control Factors in the Xishanyao Formation in the Western Part of the Southern Junggar Basin 被引量:2
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作者 YUAN Yuan SHAN Yansheng +1 位作者 TANG Yue CAO Daiyong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第2期485-500,共16页
There are abundant coal and coalbed methane(CBM)resources in the Xishanyao Formation in the western region of the southern Junggar Basin,and the prospects for CBM exploration and development are promising.To promote t... There are abundant coal and coalbed methane(CBM)resources in the Xishanyao Formation in the western region of the southern Junggar Basin,and the prospects for CBM exploration and development are promising.To promote the exploration and development of the CBM resources of the Xishanyao Formation in this area,we studied previous coalfield survey data and CBM geological exploration data.Then,we analyzed the relationships between the gas content and methane concentration vs.coal seam thickness,burial depth,coal reservoir physical characteristics,hydrogeological conditions,and roof and floor lithology.In addition,we briefly discuss the main factors influencing CBM accumulation.First,we found that the coal strata of the Xishanyao Formation in the study area are relatively simple in structure,and the coal seam has a large thickness and burial depth,as well as moderately good roof and floor conditions.The hydrogeological conditions and coal reservoir physical characteristics are also conducive to the enrichment and a high yield of CBM.We believe that the preservation of CBM resources in the study area is mainly controlled by the structure,burial depth,and hydrogeological conditions.Furthermore,on the basis of the above results,the coal seam of the Xishanyao Formation in the synclinal shaft and buried at depths of 700-1000 m should be the first considered for development. 展开更多
关键词 coalbed methane enrichment regularITY MAJOR control factors Xishanyao Formation western area of the southern JUNGGAR Basin
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An improved four-dimensional variation source term inversion model with observation error regularization
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作者 Chao-shuai Han Xue-zheng Zhu +3 位作者 Jin Gu Guo-hui Yan Xiao-hui Gao Qin-wen Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期349-360,共12页
Aiming at the Four-Dimensional Variation source term inversion algorithm proposed earlier,the observation error regularization factor is introduced to improve the prediction accuracy of the diffusion model,and an impr... Aiming at the Four-Dimensional Variation source term inversion algorithm proposed earlier,the observation error regularization factor is introduced to improve the prediction accuracy of the diffusion model,and an improved Four-Dimensional Variation source term inversion algorithm with observation error regularization(OER-4DVAR STI model)is formed.Firstly,by constructing the inversion process and basic model of OER-4DVAR STI model,its basic principle and logical structure are studied.Secondly,the observation error regularization factor estimation method based on Bayesian optimization is proposed,and the error factor is separated and optimized by two parameters:error statistical time and deviation degree.Finally,the scientific,feasible and advanced nature of the OER-4DVAR STI model are verified by numerical simulation and tracer test data.The experimental results show that OER-4DVAR STI model can better reverse calculate the hazard source term information under the conditions of high atmospheric stability and flat underlying surface.Compared with the previous inversion algorithm,the source intensity estimation accuracy of OER-4DVAR STI model is improved by about 46.97%,and the source location estimation accuracy is improved by about 26.72%. 展开更多
关键词 Source term inversion Four dimensional variation Observation error regularization factor Bayesian optimization SF6 tracer test
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Representing surface wind stress response to mesoscale SST perturbations in western coast of South America using Tikhonov regularization method 被引量:2
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作者 CUI Chaoran ZHANG Rong-Hua +1 位作者 WANG Hongna WEI Yanzhou 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第3期679-694,共16页
Interaction between mesoscale perturbations of sea surface temperature(SSTmeso)and wind stress(WSmeso)has great influences on the ocean upwelling system and turbulent mixing in the atmospheric boundary layer.Using dai... Interaction between mesoscale perturbations of sea surface temperature(SSTmeso)and wind stress(WSmeso)has great influences on the ocean upwelling system and turbulent mixing in the atmospheric boundary layer.Using daily Quik-SCAT wind speed data and AMSR-E SST data,SSTmeso and WSmeso fields in the western coast of South America are extracted by using a locally weighted regression method(LOESS).The spatial patterns of SSTmeso and WSmeso indicate strong mesoscale SST-wind stress coupling in the region.The coupling coefficient between SSTmeso and WSmeso is about 0.0095 N/(m^2·℃)in winter and 0.0082 N/(m^2·℃)in summer.Based on mesoscale coupling relationships,the mesoscale perturbations of wind stress divergence(Div(WSmeso))and curl(Curl(WSmeso))can be obtained from the SST gradient perturbations,which can be further used to derive wind stress vector perturbations using the Tikhonov regularization method.The computational examples are presented in the western coast of South America and the patterns of the reconstructed WS meso are highly consistent with SSTmeso,but the amplitude can be underestimated significantly.By matching the spatially averaged maximum standard deviations of reconstructed WSmeso magnitude and observations,a reasonable magnitude of WSmeso can be obtained when a rescaling factor of 2.2 is used.As current ocean models forced by prescribed wind cannot adequately capture the mesoscale wind stress response,the empirical wind stress perturbation model developed in this study can be used to take into account the feedback effects of the mesoscale wind stress-SST coupling in ocean modeling.Further applications are discussed for taking into account the feedback effects of the mesoscale coupling in largescale climate models and the uncoupled ocean models. 展开更多
关键词 MESOSCALE AIR-SEA coupling Tikhonov’s regularization method WESTERN COAST of South AMERICA
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