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三维稳态Q-tensor液晶流系统各向异性的Liouville型定理
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作者 胡立立 曹志杰 别群益 《应用数学》 北大核心 2024年第3期629-635,共7页
考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<... 考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<q<∞,则该稳态系统只有平凡解.这个结论推广了已有的结果. 展开更多
关键词 LIOUVILLE型定理 液晶流 各向异性 Q-tensor
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Euler Product Expressions of Absolute Tensor Products of Dirichlet L-Functions
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作者 Hidenori Tanaka Shin-ya Koyama 《Advances in Pure Mathematics》 2024年第6期451-486,共36页
In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a se... In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a series which has the factors of the absolute tensor product of the Dirichlet L-functions. This study is a generalization of Akatsuka’s theorem on the Riemann zeta function, and gives a proof of Kurokawa’s prediction proposed in 1992. 展开更多
关键词 Dirichlet L-Function Absolute tensor Product (Kurokawa tensor Product) Euler Product
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Fault Diagnosis Scheme for Railway Switch Machine Using Multi-Sensor Fusion Tensor Machine
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作者 Chen Chen Zhongwei Xu +2 位作者 Meng Mei Kai Huang Siu Ming Lo 《Computers, Materials & Continua》 SCIE EI 2024年第6期4533-4549,共17页
Railway switch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railway switch machine using tensor machine and multi-representation monitori... Railway switch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railway switch machine using tensor machine and multi-representation monitoring data is developed herein.Unlike existing methods,this approach takes into account the spatial information of the time series monitoring data,aligning with the domain expertise of on-site manual monitoring.Besides,a multi-sensor fusion tensor machine is designed to improve single signal data’s limitations in insufficient information.First,one-dimensional signal data is preprocessed and transformed into two-dimensional images.Afterward,the fusion feature tensor is created by utilizing the images of the three-phase current and employing the CANDE-COMP/PARAFAC(CP)decomposition method.Then,the tensor learning-based model is built using the extracted fusion feature tensor.The developed fault diagnosis scheme is valid with the field three-phase current dataset.The experiment indicates an enhanced performance of the developed fault diagnosis scheme over the current approach,particularly in terms of recall,precision,and F1-score. 展开更多
关键词 Railway switch machine tensor machine fault diagnosis
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Optimizing Recovery Following Mihata Superior Capsular Reconstruction Surgery with Tensor Fascia Lata Auto Graft: A Comprehensive Rehabilitation Protocol
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作者 Paul B. Roache Noman Naqvi 《Open Journal of Orthopedics》 2024年第10期441-452,共12页
Objective: Superior Capsular Reconstruction (SCR) using a Tensor Fascia Lata (TFL) autograft is an evolving technique for treating irreparable rotator cuff tears. The Mihata technique, initially developed in Japan, ha... Objective: Superior Capsular Reconstruction (SCR) using a Tensor Fascia Lata (TFL) autograft is an evolving technique for treating irreparable rotator cuff tears. The Mihata technique, initially developed in Japan, has shown promising long-term results. However, a standardized post-operative rehabilitation protocol for this procedure in the USA is lacking. Purpose: This study aims to evaluate the outcomes of a comprehensive rehabilitation protocol following SCR with TFL autograft in a cohort of nine patients. Participants and Methods: A prospective observational study was conducted at Concentra Urgent Care, San Francisco. Nine patients, aged 55 - 65 years, underwent SCR with TFL autograft performed by a specialized orthopedic surgeon. Post-operative rehabilitation was managed using a structured protocol, divided into three phases focusing on passive exercises, progressive range of motion, and strengthening. Outcomes were measured using the Visual Analogue Scale (VAS) for pain, forward flexion range of motion (FF-ROM), and Single Assessment Numeric Evaluation (SANE) scores over a six-month period. Results: Significant improvements were observed in pain reduction (mean VAS decrease of −3.67 points, p = 0.01), ROM (mean FF increase of 41.11 degrees, p = 0.014), and SANE scores (mean improvement of 42.11%, p = 0.009), indicating the efficacy of the rehabilitation protocol. Conclusion: The comprehensive rehabilitation protocol following SCR with TFL autograft significantly improved pain, range of motion, and shoulder function in patients, suggesting its potential utility in clinical practice. 展开更多
关键词 Superior Capsular Reconstruction tensor Fascia Lata Rotator Cuff Tears Rehabilitation Protocol
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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints
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作者 Guiyun Gao Chenghu Wang Ke Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1637-1648,共12页
The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determinati... The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable results.In this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests required.Different shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo method.Thereafter,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress constraints.The inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress tensor.Two stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)method.The results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress gradient.The inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints employed.The M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole. 展开更多
关键词 Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing
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Quantum geometric tensor and the topological characterization of the extended Su-Schrieffer-Heeger model
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作者 曾相龙 赖文喜 +1 位作者 魏祎雯 马余全 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期260-265,共6页
We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger(SSH)model with long-range hopping terms.By computing the quantum geometry tensor,we derive exact expression... We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger(SSH)model with long-range hopping terms.By computing the quantum geometry tensor,we derive exact expressions for the quantum metric and Berry curvature of the energy band electrons,and we obtain the phase diagram of the model marked by the first Chern number.Furthermore,we also obtain the topological Euler number of the energy band based on the Gauss-Bonnet theorem on the topological characterization of the closed Bloch states manifold in the first Brillouin zone.However,some regions where the Berry curvature is identically zero in the first Brillouin zone result in the degeneracy of the quantum metric,which leads to ill-defined non-integer topological Euler numbers.Nevertheless,the non-integer"Euler number"provides valuable insights and an upper bound for the absolute values of the Chern numbers. 展开更多
关键词 quantum geometric tensor topological Euler number Chern number Berry curvature quantum metric Su-Schrieffer-Heeger(SSH)model
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Implementing and evaluating an automatic centroid moment tensor procedure for the Indonesia region and surrounding areas
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作者 Madlazim Muhammad Nurul Fahmi +2 位作者 Dyah Permata Sari Ella Meilianda Sorja Koesuma 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期609-620,共12页
The purpose of this research was to suggest an applicable procedure for computing the centroid moment tensor(CMT)automatically and in real time from earthquakes that occur in Indonesia and the surrounding areas.Gisola... The purpose of this research was to suggest an applicable procedure for computing the centroid moment tensor(CMT)automatically and in real time from earthquakes that occur in Indonesia and the surrounding areas.Gisola software was used to estimate the CMT solution by selecting the velocity model that best suited the local and regional geological conditions in Indonesia and the surrounding areas.The data used in this study were earthquakes with magnitudes of 5.4 to 8.0.High-quality,real-time broadband seismographic data were provided by the International Federation of Digital Seismograph Networks Web Services(FDSNWS)and the European Integrated Data Archive(EIDA)Federation in Indonesia and the surrounding areas.Furthermore,the inversion process and filter adjustment were carried out on the seismographic data to obtain good CMT solutions.The CMT solutions from Gisola provided good-quality solutions,in which all earthquake data had A-level quality(high quality,with good variant reduction).The Gisola CMT solution was justified with the Global CMT(GCMT)solution by using the Kagan angle value,with an average of approximately 11.2°.This result suggested that the CMT solution generated from Gisola was trustworthy and reliable.The Gisola CMT solution was typically available within approximately 15 minutes after an earthquake occurred.Once it met the quality requirement,it was automatically published on the internet.The catalog of local and regional earthquake records obtained through this technology holds great promise for improving the current understanding of regional seismic activity and ongoing tectonic processes.The accurate and real-time CMT solution generated by implementing the Gisola algorithm consisted of moment tensors and moment magnitudes,which provided invaluable insights into earthquakes occurring in Indonesia and the surrounding areas. 展开更多
关键词 centroid moment tensor Gisola International Federation of Digital Seismograph Networks Web Services(FDSNWS) real time Indonesia
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A Novel Tensor Decomposition-Based Efficient Detector for Low-Altitude Aerial Objects With Knowledge Distillation Scheme
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作者 Nianyin Zeng Xinyu Li +2 位作者 Peishu Wu Han Li Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期487-501,共15页
Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computati... Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computational resources. In this paper, the LAA images-oriented tensor decomposition and knowledge distillation-based network(TDKD-Net) is proposed,where the TT-format TD(tensor decomposition) and equalweighted response-based KD(knowledge distillation) methods are designed to minimize redundant parameters while ensuring comparable performance. Moreover, some robust network structures are developed, including the small object detection head and the dual-domain attention mechanism, which enable the model to leverage the learned knowledge from small-scale targets and selectively focus on salient features. Considering the imbalance of bounding box regression samples and the inaccuracy of regression geometric factors, the focal and efficient IoU(intersection of union) loss with optimal transport assignment(F-EIoU-OTA)mechanism is proposed to improve the detection accuracy. The proposed TDKD-Net is comprehensively evaluated through extensive experiments, and the results have demonstrated the effectiveness and superiority of the developed methods in comparison to other advanced detection algorithms, which also present high generalization and strong robustness. As a resource-efficient precise network, the complex detection of small and occluded LAA objects is also well addressed by TDKD-Net, which provides useful insights on handling imbalanced issues and realizing domain adaptation. 展开更多
关键词 Attention mechanism knowledge distillation(KD) object detection tensor decomposition(TD) unmanned aerial vehicles(UAVs)
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Least Squares One-Class Support Tensor Machine
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作者 Kaiwen Zhao Yali Fan 《Journal of Computer and Communications》 2024年第4期186-200,共15页
One-class classification problem has become a popular problem in many fields, with a wide range of applications in anomaly detection, fault diagnosis, and face recognition. We investigate the one-class classification ... One-class classification problem has become a popular problem in many fields, with a wide range of applications in anomaly detection, fault diagnosis, and face recognition. We investigate the one-class classification problem for second-order tensor data. Traditional vector-based one-class classification methods such as one-class support vector machine (OCSVM) and least squares one-class support vector machine (LSOCSVM) have limitations when tensor is used as input data, so we propose a new tensor one-class classification method, LSOCSTM, which directly uses tensor as input data. On one hand, using tensor as input data not only enables to classify tensor data, but also for vector data, classifying it after high dimensionalizing it into tensor still improves the classification accuracy and overcomes the over-fitting problem. On the other hand, different from one-class support tensor machine (OCSTM), we use squared loss instead of the original loss function so that we solve a series of linear equations instead of quadratic programming problems. Therefore, we use the distance to the hyperplane as a metric for classification, and the proposed method is more accurate and faster compared to existing methods. The experimental results show the high efficiency of the proposed method compared with several state-of-the-art methods. 展开更多
关键词 Least Square One-Class Support tensor Machine One-Class Classification Upscale Least Square One-Class Support Vector Machine One-Class Support tensor Machine
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关于Focal Loss的Tensor Train多项式分类器
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作者 刘思宏 《计算机应用文摘》 2024年第6期111-114,117,共5页
在模式分类领域,多项式分类器因其复杂决策边界能力而得到广泛研究。利用TensorTrain分解形式来表示多项式分类器,可有效克服维数灾难。针对多项式分类器在训练过程中遇到的训练集分布不平衡问题,文章使用FocalLoss重塑了标准交叉损失,... 在模式分类领域,多项式分类器因其复杂决策边界能力而得到广泛研究。利用TensorTrain分解形式来表示多项式分类器,可有效克服维数灾难。针对多项式分类器在训练过程中遇到的训练集分布不平衡问题,文章使用FocalLoss重塑了标准交叉损失,以降低分配给易分类样本的损失的权重,并在被广泛使用的图像分类数据集MNIST上验证了分类器的有效性。 展开更多
关键词 监督学习 张量分解 多项式分类器 图像分类
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Solution of the Matrix Second Semi-Tensor Product Equation A ∘ l X ∘ l B=C
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作者 Hao Zhang 《Journal of Applied Mathematics and Physics》 2024年第10期3261-3280,共20页
In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time,... In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time, the compatibility conditions, the sufficient and necessary conditions and the specific solution methods for the matrix solution are given. Secondly, we further consider the solvability of the second semi-tensor product equation of the matrix. For each part, several examples are given to illustrate the validity of the results. 展开更多
关键词 Matrix Equation The Second Semi-tensor Product Compatibility Condition Sufficient and Necessary Conditions VECTORIZATION
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Verification of neutron-induced fission product yields evaluated by a tensor decompsition model in transport-burnup simulations 被引量:5
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作者 Qu‑Fei Song Long Zhu +1 位作者 Hui Guo Jun Su 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期190-201,共12页
Neutron-induced fission is an important research object in basic science.Moreover,its product yield data are an indispensable nuclear data basis in nuclear engineering and technology.The fission yield tensor decomposi... Neutron-induced fission is an important research object in basic science.Moreover,its product yield data are an indispensable nuclear data basis in nuclear engineering and technology.The fission yield tensor decomposition(FYTD)model has been developed and used to evaluate the independent fission product yield.In general,fission yield data are verified by the direct comparison of experimental and evaluated data.However,such direct comparison cannot reflect the impact of the evaluated data on application scenarios,such as reactor transport-burnup simulation.Therefore,this study applies the evaluated fission yield data in transport-burnup simulation to verify their accuracy and possibility of application.Herein,the evaluated yield data of235U and239Pu are applied in the transport-burnup simulation of a pressurized water reactor(PWR)and sodium-cooled fast reactor(SFR)for verification.During the reactor operation stage,the errors in pin-cell reactivity caused by the evaluated fission yield do not exceed 500 and 200 pcm for the PWR and SFR,respectively.The errors in decay heat and135Xe and149Sm concentrations during the short-term shutdown of the PWR are all less than 1%;the errors in decay heat and activity of the spent fuel of the PWR and SFR during the temporary storage stage are all less than 2%.For the PWR,the errors in important nuclide concentrations in spent fuel,such as90Sr,137Cs,85Kr,and99Tc,are all less than 6%,and a larger error of 37%is observed on129I.For the SFR,the concentration errors of ten important nuclides in spent fuel are all less than 16%.A comparison of various aspects reveals that the transport-burnup simulation results using the FYTD model evaluation have little difference compared with the reference results using ENDF/B-Ⅷ.0 data.This proves that the evaluation of the FYTD model may have application value in reactor physical analysis. 展开更多
关键词 Fission product yield tensor decomposition Transport-burnup simulation Machine learning
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Analysis of rockburst mechanism and warning based on microseismic moment tensors and dynamic Bayesian networks 被引量:4
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作者 Haoyu Mao Nuwen Xu +4 位作者 Xiang Li Biao Li Peiwei Xiao Yonghong Li Peng Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2521-2538,共18页
One of the major factors inhibiting the construction of deep underground projects is the risk posed by rockbursts.A study was conducted on the access tunnel of the Shuangjiangkou hydropower station to determine the ev... One of the major factors inhibiting the construction of deep underground projects is the risk posed by rockbursts.A study was conducted on the access tunnel of the Shuangjiangkou hydropower station to determine the evolutionary mechanism of microfractures within the surrounding rock mass during rockburst development and develop a rockburst warning model.The study area was chosen through the combination of field studies with an analysis of the spatial and temporal distribution of microseismic(MS)events.The moment tensor inversion method was adopted to study rockburst mechanism,and a dynamic Bayesian network(DBN)was applied to investigating the sensitivity of MS source parameters for rockburst warnings.A MS multivariable rockburst warning model was proposed and validated using two case studies.The results indicate that fractures in the surrounding rock mass during the development of strain-structure rockbursts initially show shear failure and are then followed by tensile failure.The effectiveness of the DBN-based rockburst warning model was demonstrated using self-validation and K-fold cross-validation.Moment magnitude and source radius are the most sensitive factors based on an investigation of the influence on the parent and child nodes in the model,which can serve as important standards for rockburst warnings.The proposed rockburst warning model was found to be effective when applied to two actual projects. 展开更多
关键词 Microseismic monitoring Moment tensor Dynamic Bayesian network(DBN) Rockburst warning Shuangjiangkou hydropower station
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GPU-acceleration 3D rotated-staggered-grid solutions to microseismic anisotropic wave equation with moment tensor implementation 被引量:1
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作者 Jing Zheng Lingbin Meng +1 位作者 Yuan Sun Suping Peng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第4期403-410,共8页
To improve the accuracy of microseismic inversion,seismic anisotropy and moment tensor source should be carefully considered in the forward modelling stage.In this study,3D microseismic anisotropy wave forward modelli... To improve the accuracy of microseismic inversion,seismic anisotropy and moment tensor source should be carefully considered in the forward modelling stage.In this study,3D microseismic anisotropy wave forward modelling with a moment tensor source was proposed.The modelling was carried out based on a rotated-staggered-grid(RSG)scheme.In contrast to staggered-grids,the RSG scheme defines the velocity components and densities at the same grid,as do the stress components and elastic parameters.Therefore,the elastic moduli do not need to be interpolated.In addition,the detailed formulation and implementation of moment-tensor source loaded on the RSG was presented by equating the source to the stress increments.Meanwhile,the RSG-based 3D wave equation forward modelling was performed in parallel using compute unified device architecture(CUDA)programming on a graphics processing unit(GPU)to improve its efficiency.Numerical simulations including homogeneous and anisotropic models were carried out using the method proposed in this paper,and compared with other methods to prove the reliability of this method.Furthermore,the high efficiency of the proposed approach was evaluated.The results show that the computational efficiency of proposed method can be improved by about two orders of magnitude compared with traditional central processing unit(CPU)computing methods.It could not only help the analysis of microseismic full wavefield records,but also provide support for passive source inversion,including location and focal mechanism inversion,and velocities inversion. 展开更多
关键词 Microseismic Forward modelling Seismic anisotropy Moment tensor
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Diffusion tensor imaging of horizontal extraocular muscles in patients with concomitant and paralytic esotropia 被引量:1
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作者 Ming-Hao Chen Jian-Hua Yan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第8期1350-1355,共6页
AIM:To assess metrics of diffusion tensor imagining(DTI)in evaluating microstructural abnormalities of horizontal extraocular muscles(EOM)in esotropia.METHODS:Six adult concomitant esotropia patients,5 unilateral abdu... AIM:To assess metrics of diffusion tensor imagining(DTI)in evaluating microstructural abnormalities of horizontal extraocular muscles(EOM)in esotropia.METHODS:Six adult concomitant esotropia patients,5 unilateral abducent paralysis patients and 2 healthy volunteers were enrolled.Conventional magnetic resonance imaging(MRI)and DTI were performed on all subjects using 3T MR scanner.Fractional anisotropy(FA),mean diffusivity(MD),axial diffusivity(AD),and radial diffusivity(RD)of medial and lateral rectus muscles were measured and compared between patients group and control group.RESULTS:Medial rectus MD and RD within the adducted eye of concomitant patients was significantly greater than that in unilateral abducent paralysis patients(0.259×10-2 mm^(2)/s vs 0.207×10-2 mm^(2)/s,P=0.014;0.182×10-2 mm^(2)/s vs 0.152×10-2 mm^(2)/s,P=0.017).Both strabismus patients showed a significantly decreased MD and AD than that obtained in normal controls for lateral rectus muscles(P<0.05).Medial rectus MD of the adducted eye in concomitant strabismus patients was significantly decreased than that in healthy controls(0.259×10-2 mm^(2)/s vs 0.266×10-2 mm^(2)/s,P=0.010).Lateral rectus AD of the adducted eye in concomitant strabismus patients was significantly decreased as compared with that in healthy controls(0.515×10-2 mm^(2)/s vs 0.593×10-2 mm^(2)/s,P=0.013).No statistically significant differences were present between the adducted and fixating eyes in concomitant strabismus patients.CONCLUSION:DTI represents a feasible technique to assess tissue characteristics of EOM.The effects of eye position changes on DTI parameters are subtle.Decreased MD and RD could be evidence for remodeling of the medial rectus muscle contracture.Lower medial and lateral recuts MD of concomitant esotropia patients indicates a thinner fibrous structure of the EOM.Lower MD and AD should be general character of esotropia. 展开更多
关键词 diffusion tensor imagining extraocular muscle ESOTROPIA STRABISMUS
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Popularity Prediction of Social Media Post Using Tensor Factorization 被引量:1
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作者 Navdeep Bohra Vishal Bhatnagar +3 位作者 Amit Choudhary Savita Ahlawat Dinesh Sheoran Ashish Kumari 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期205-221,共17页
The traditional method of doing business has been disrupted by socialmedia. In order to develop the enterprise, it is essential to forecast the level ofinteraction that a new post would receive from social media users... The traditional method of doing business has been disrupted by socialmedia. In order to develop the enterprise, it is essential to forecast the level ofinteraction that a new post would receive from social media users. It is possiblefor the user’s interest in any one social media post to be impacted by external factors or to dwindle as a result of changes in his behaviour. The popularity detectionstrategies that are user-based or population-based are unable to keep up with theseshifts, which leads to inaccurate forecasts. This work makes a prediction abouthow popular the post will be and addresses any anomalies caused by factors outside of the study. A novel improved PARAFAC (A-PARAFAC) method that istensor factorization-based has been presented in order to cope with the user criteria that will be used in the future to rate any project. We consolidated the information on the historically popular content, and we accelerated the computation bychoosing the top contents that were most like each other. The tensor is factorisedwith the application of the Adam optimization. It has been modified such that thebias is now included in the gradient function of A-PARAFAC, and the value ofthe bias is updated after each iteration. The prediction accuracy is improved by32.25% with this strategy compared to other state of the art methods. 展开更多
关键词 tensor decomposition popularity prediction group level popularity graphical clustering PARAFAC
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Diffusion tensor imaging reveals brain structure changes in dogs after spinal cord injury 被引量:1
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作者 Chang-Bin Liu De-Gang Yang +5 位作者 Jun Li Chuan Qin Xin Zhang Jun Liu Da-Peng Li Jian-Jun Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期176-182,共7页
Based on the Wallerian degeneration in the spinal cord pathways,the changes in synaptic connections,and the spinal cord-related cellular responses that alter the cellular structure of the brain,we presumed that brain ... Based on the Wallerian degeneration in the spinal cord pathways,the changes in synaptic connections,and the spinal cord-related cellular responses that alter the cellular structure of the brain,we presumed that brain diffusion tensor imaging(DTI)parameters may change after spinal cord injury.However,the dynamic changes in DTI parameters remain unclear.We established a Beagle dog model of T10 spinal cord contusion and performed DTI of the injured spinal cord.We found dynamic changes in DTI parameters in the cerebral peduncle,posterior limb of the internal capsule,pre-and postcentral gyri of the brain within 12 weeks after spinal cord injury.We then performed immunohistochemistry to detect the expression of neurofilament heavy polypeptide(axonal marker),glial fibrillary acidic protein(glial cell marker),and NeuN(neuronal marker).We found that these pathological changes were consistent with DTI parameter changes.These findings suggest that DTI can display brain structure changes after spinal cord injury. 展开更多
关键词 spinal cord injury diffusion tensor imaging CANINES PATHOPHYSIOLOGY cerebrospinal structures corticospinal tract magnetic resonance imaging anisotropic fraction apparent dispersion coefficient
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Application of tensor CSAMT with high-power orthogonal signal sources in Jiama porphyry copper deposit,South Tibet 被引量:2
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作者 Peng-liang Yu Ting Qu +3 位作者 Ri-zheng He Jian-li Liu Su-fen Wang Xiao-long Chen 《China Geology》 CAS CSCD 2023年第1期37-49,共13页
The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) t.Howeve... The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) t.However,it features wavy and steep terrain,leading to extremely difficult field operation and heavy interference.This study attempts to determine the effects of the tensor controlled-source audiomagnetotellurics(CSAMT)with high-power orthogonal signal sources(also referred to as the high-power tensor CSAMT)when it is applied to the deep geophysical exploration in plateaus with complex terrain and mining areas with strong interference.The test results show that the high current provided by the highpower tensor CSAMT not only greatly improved the signal-to-noise ratio but also guaranteed that effective signals were received in the case of a long transmitter-receiver distance.Meanwhile,the tensor data better described the anisotropy of deep geologic bodies.In addition,the tests also show that when the transmitting current reaches 60 A,it is still guaranteed that strong enough signals can be received in the case of the transmitter-receiver distance of about 25 km,sounding curves show no near field effect,and effective exploration depth can reach 3 km.The 2D inversion results are roughly consistent with drilling results,indicating that the high-power tensor CSAMT can be used to achieve nearly actual characteristics of underground electrical structures.Therefore,this method has great potential for application in deep geophysical exploration in plateaus and mining areas with complex terrain and strong interference,respectively.This study not only serves as important guidance on the prospecting in the Qinghai-Tibet Plateau but also can be used as positive references for deep mineral exploration in other areas. 展开更多
关键词 Jiama porphyry copper deposit Supergiant copper polymetallic deposit tensor CSAMT of 150 kw High power 2D inversion Deep prospecting Mineral exploration engineering Xizang(Tibet)
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An Alternative Way to Mapping Cone: The Algebraic Topology of the Pinched Tensor
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作者 Yousuf Alkhezi 《Applied Mathematics》 2023年第11期719-727,共9页
In this research, we explore the properties and applications of the mapping cone and its variant, the pinched mapping cone. The mapping cone is a construction that arises naturally in algebraic topology and is used to... In this research, we explore the properties and applications of the mapping cone and its variant, the pinched mapping cone. The mapping cone is a construction that arises naturally in algebraic topology and is used to study the homotopy type of spaces. It has several key properties, including its homotopy equivalence to the cofiber of a continuous map, and its ability to compute homotopy groups using the long exact sequence associated with the cofiber. We also provide an overview of the properties and applications of the mapping cone and the pinched mapping cone in algebraic topology. This work highlights the importance of these constructions in the study of homotopy theory and the calculation of homotopy groups. The study also points to the potential for further research in this area which includes the study of higher homotopy groups and the applications of these constructions to other areas of mathematics. 展开更多
关键词 Complex tensor Product Pinched tensor Product Mapping Cone MORPHISM
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Research on infrared dim and small target detection algorithm based on low-rank tensor recovery
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作者 LIU Chuntong WANG Hao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期861-872,共12页
In order to rapidly and accurately detect infrared small and dim targets in the infrared image of complex scene collected by virtual prototyping of space-based downward-looking multiband detection,an improved detectio... In order to rapidly and accurately detect infrared small and dim targets in the infrared image of complex scene collected by virtual prototyping of space-based downward-looking multiband detection,an improved detection algorithm of infrared small and dim target is proposed in this paper.Firstly,the original infrared images are changed into a new infrared patch tensor mode through data reconstruction.Then,the infrared small and dim target detection problems are converted to low-rank tensor recovery problems based on tensor nuclear norm in accordance with patch tensor characteristics,and inverse variance weighted entropy is defined for self-adaptive adjustment of sparseness.Finally,the low-rank tensor recovery problem with noise is solved by alternating the direction method to obtain the sparse target image,and the final small target is worked out by a simple partitioning algorithm.The test results in various spacebased downward-looking complex scenes show that such method can restrain complex background well by virtue of rapid arithmetic speed with high detection probability and low false alarm rate.It is a kind of infrared small and dim target detection method with good performance. 展开更多
关键词 complex scene infrared block tensor tensor kernel norm low-rank tensor restoration weighted inverse entropy alternating direction method
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