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The SPARC-related modular calcium binding 1(Smoc1)regulated by androgen is required for mouse gubernaculum development and testicular descent
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作者 Zhi-Yi Zhao Yong Siow +3 位作者 Ling-Yun Liu Xian Li Hong-Liang Wang Zhen-Min Lei 《Asian Journal of Andrology》 2025年第1期44-51,共8页
Testicular descent occurs in two consecutive stages:the transabdominal stage and the inguinoscrotal stage.Androgens play a crucial role in the second stage by influencing the development of the gubernaculum,a structur... Testicular descent occurs in two consecutive stages:the transabdominal stage and the inguinoscrotal stage.Androgens play a crucial role in the second stage by influencing the development of the gubernaculum,a structure that pulls the testis into the scrotum.However,the mechanisms of androgen actions underlying many of the processes associated with gubernaculum development have not been fully elucidated.To identify the androgen-regulated genes,we conducted large-scale gene expression analyses on the gubernaculum harvested from luteinizing hormone/choriogonadotropin receptor knockout(Lhcgr KO)mice,an animal model of inguinoscrotal testis maldescent resulting from androgen deficiency.We found that the expression of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 1(Smoc1)was the most severely suppressed at both the transcript and protein levels,while its expression was the most dramatically induced by testosterone administration in the gubernacula of Lhcgr KO mice.The upregulation of Smoc1 expression by testosterone was curtailed by the addition of an androgen receptor antagonist,flutamide.In addition,in vitro studies demonstrated that SMOC1 modestly but significantly promoted the proliferation of gubernacular cells.In the cultures of myogenic differentiation medium,both testosterone and SMOC1 enhanced the expression of myogenic regulatory factors such as paired box 7(Pax7)and myogenic factor 5(Myf5).After short-interfering RNA-mediated knocking down of Smoc1,the expression of Pax7 and Myf5 diminished,and testosterone alone did not recover,but additional SMOC1 did.These observations indicate that SMOC1 is pivotal in mediating androgen action to regulate gubernaculum development during inguinoscrotal testicular descent. 展开更多
关键词 ANDROGEN androgen receptor GUBERNACULUM Smoc1 testis descent
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Classifying Multi-Lingual Reviews Sentiment Analysis in Arabic and English Languages Using the Stochastic Gradient Descent Model
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作者 Yasser Alharbi Sarwar Shah Khan 《Computers, Materials & Continua》 2025年第4期1275-1290,共16页
Sentiment analysis plays an important role in distilling and clarifying content from movie reviews,aiding the audience in understanding universal views towards the movie.However,the abundance of reviews and the risk o... Sentiment analysis plays an important role in distilling and clarifying content from movie reviews,aiding the audience in understanding universal views towards the movie.However,the abundance of reviews and the risk of encountering spoilers pose challenges for efcient sentiment analysis,particularly in Arabic content.Tis study proposed a Stochastic Gradient Descent(SGD)machine learning(ML)model tailored for sentiment analysis in Arabic and English movie reviews.SGD allows for fexible model complexity adjustments,which can adapt well to the Involvement of Arabic language data.Tis adaptability ensures that the model can capture the nuances and specifc local patterns of Arabic text,leading to better performance.Two distinct language datasets were utilized,and extensive pre-processing steps were employed to optimize the datasets for analysis.Te proposed SGD model,designed to accommodate the nuances of each language,aims to surpass existing models in terms of accuracy and efciency.Te SGD model achieves an accuracy of 84.89 on the Arabic dataset and 87.44 on the English dataset,making it the top-performing model in terms of accuracy on both datasets.Tis indicates that the SGD model consistently demonstrates high accuracy levels across Arabic and English datasets.Tis study helps deepen the understanding of sentiments across various linguistic datasets.Unlike many studies that focus solely on movie reviews,the Arabic dataset utilized here includes hotel reviews,ofering a broader perspective. 展开更多
关键词 Sentiment analysis stochastic gradient descent REVIEWS English IMDb dataset Arabic dataset
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超椭圆曲线离散对数的Weil Descent代数攻击的分析 被引量:1
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作者 张方国 王育民 《通信学报》 EI CSCD 北大核心 2002年第3期1-9,共9页
本文首先介绍了Galbraith的Weil Descent代数攻击方法,然后对定义在GF(qn)上的形如y2+xy=f(x)的HCDLP能否用Weil Descent代数方法攻击作了详细讨论,作为例子,研究了GF(4)和GF(8)上的这类曲线。得到结论:(1)Weil Descent代数攻击法只能... 本文首先介绍了Galbraith的Weil Descent代数攻击方法,然后对定义在GF(qn)上的形如y2+xy=f(x)的HCDLP能否用Weil Descent代数方法攻击作了详细讨论,作为例子,研究了GF(4)和GF(8)上的这类曲线。得到结论:(1)Weil Descent代数攻击法只能适用于极少部分这类超椭圆曲线;(2)当亏格或基域增大时,Weil Descent方法攻击成功的概率趋向于0。所以说Weil Descent代数攻击法对建立在GF(2n)上的这类超椭圆曲线密码体制并没有太大的威胁。 展开更多
关键词 超椭圆曲线密码体制 Weildescent攻击 代数攻击 保密通信
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SPECTRAL MAPPING THEOREM FOR ASCENT,ESSENTIAL ASCENT, DESCENT AND ESSENTIAL DESCENT SPECTRUM OF LINEAR RELATIONS
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作者 Ezzeddine CHAFAI Maher MNIF 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1212-1224,共13页
In [7], Cross showed that the spectrum of a linear relation T on a normed space satisfies the spectral mapping theorem. In this paper, we extend the notion of essential ascent and descent for an operator acting on a v... In [7], Cross showed that the spectrum of a linear relation T on a normed space satisfies the spectral mapping theorem. In this paper, we extend the notion of essential ascent and descent for an operator acting on a vector space to linear relations acting on Banach spaces. We focus to define and study the descent, essential descent, ascent and essential ascent spectrum of a linear relation everywhere defined on a Banach space X. In particular, we show that the corresponding spectrum satisfy the polynomial version of the spectral mapping theorem. 展开更多
关键词 ASCENT essential ascent descent essential descent linear relations
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Supervised descent method for weld pool boundary extraction during fiber laser welding process 被引量:6
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作者 Zhao Yaobang Zhang Dengming +1 位作者 Wu Yuanfeng Yang Changqi 《China Welding》 EI CAS 2019年第1期6-10,共5页
In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainl... In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainless steel is welded by a 5 kW high-power fiber laser and a high-speed camera is employed to capture the topside images of weld pools. Then we propose a robust visual-detection approach for the molten pool based on the supervised descent method. It provides an elegant framework for representing the outline of a weld pool and is especially efficient for weld pool detection in the presence of strong uncertainties and disturbances. Finally, welding experimental results verified that the proposed approach can extract the weld pool boundary accurately, which will lay a solid foundation for controlling the weld quality of fiber laser welding process. 展开更多
关键词 fiber laser WELDING MOLTEN POOL supervised descent method BOUNDARY extraction
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A Coordinate Gradient Descent Method for Nonsmooth Nonseparable Minimization 被引量:9
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作者 Zheng-Jian Bai Michael K. Ng Liqun Qi 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期377-402,共26页
This paper presents a coordinate gradient descent approach for minimizing the sum of a smooth function and a nonseparable convex function.We find a search direction by solving a subproblem obtained by a second-order a... This paper presents a coordinate gradient descent approach for minimizing the sum of a smooth function and a nonseparable convex function.We find a search direction by solving a subproblem obtained by a second-order approximation of the smooth function and adding a separable convex function.Under a local Lipschitzian error bound assumption,we show that the algorithm possesses global and local linear convergence properties.We also give some numerical tests(including image recovery examples) to illustrate the efficiency of the proposed method. 展开更多
关键词 Coordinate descent global convergence linear convergence rate
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Efficient and High-quality Recommendations via Momentum-incorporated Parallel Stochastic Gradient Descent-Based Learning 被引量:7
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作者 Xin Luo Wen Qin +2 位作者 Ani Dong Khaled Sedraoui MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第2期402-411,共10页
A recommender system(RS)relying on latent factor analysis usually adopts stochastic gradient descent(SGD)as its learning algorithm.However,owing to its serial mechanism,an SGD algorithm suffers from low efficiency and... A recommender system(RS)relying on latent factor analysis usually adopts stochastic gradient descent(SGD)as its learning algorithm.However,owing to its serial mechanism,an SGD algorithm suffers from low efficiency and scalability when handling large-scale industrial problems.Aiming at addressing this issue,this study proposes a momentum-incorporated parallel stochastic gradient descent(MPSGD)algorithm,whose main idea is two-fold:a)implementing parallelization via a novel datasplitting strategy,and b)accelerating convergence rate by integrating momentum effects into its training process.With it,an MPSGD-based latent factor(MLF)model is achieved,which is capable of performing efficient and high-quality recommendations.Experimental results on four high-dimensional and sparse matrices generated by industrial RS indicate that owing to an MPSGD algorithm,an MLF model outperforms the existing state-of-the-art ones in both computational efficiency and scalability. 展开更多
关键词 Big data industrial application industrial data latent factor analysis machine learning parallel algorithm recommender system(RS) stochastic gradient descent(SGD)
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Numerical investigation of full scale coaxial main rotor aerodynamics in hover and vertical descent 被引量:6
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作者 Pavel V.MAKEEV Yuri M.IGNATKIN Alexander I.SHOMOV 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第5期666-683,共18页
The original free vortex wake model was used for numerical investigation.Calculation of the aerodynamic characteristics in hover and vertical descent modes in the range of vertical descent speed of 0–30 m/s including... The original free vortex wake model was used for numerical investigation.Calculation of the aerodynamic characteristics in hover and vertical descent modes in the range of vertical descent speed of 0–30 m/s including the Vortex Ring State(VRS)area was performed.The calculations were carried out under the condition of variable blade pitch angle values providing a fixed timeaverage thrust value.Visualization data of free vortex wake shapes,flow structures,and velocity fields were obtained and analyzed.The time-dependences of the rotor’s thrust and torque coefficients were obtained and analyzed.The obtained data allows determining the boundaries of the VRS area by various criteria such as rotor thrust and torque pulsations,growth of rotor power consumption relative to the hover,growth of rotor induced velocities relative to the hover,and growth of the required rotor blade pitch angles values.The results of the study are compared with experimental and calculated data of other authors and can significantly supplement the available results of experimental and computational studies in this area. 展开更多
关键词 Aerodynamic characteristics Coaxial rotor Free wake model Hover and vertical descent Vortex ring state mode
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Distributed stochastic mirror descent algorithm for resource allocation problem 被引量:2
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作者 Yinghui Wang Zhipeng Tu Huashu Qin 《Control Theory and Technology》 EI CSCD 2020年第4期339-347,共9页
In this paper,we consider a distributed resource allocation problem of minimizing a global convex function formed by a sum of local convex functions with coupling constraints.Based on neighbor communication and stocha... In this paper,we consider a distributed resource allocation problem of minimizing a global convex function formed by a sum of local convex functions with coupling constraints.Based on neighbor communication and stochastic gradient,a distributed stochastic mirror descent algorithm is designed for the distributed resource allocation problem.Sublinear convergence to an optimal solution of the proposed algorithm is given when the second moments of the gradient noises are summable.A numerical example is also given to illustrate the effectiveness of the proposed algorithm. 展开更多
关键词 DISTRIBUTED Resource allocation problem Stochastic gradient Mirror descent
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Evaluation of Burden Descent Model for Burden Distribution in Blast Furnace 被引量:5
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作者 Ping ZHOU Peng-yu SHI +3 位作者 Yan-po SONG Kai-le TANG Dong FU Chenn Q.ZHOU 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第8期765-771,共7页
Mathematical models for burden descending process have been applied to obtain whole burden structures in blast furnace,whereas the accuracy of those burden descent models has not been sufficiently investigated.Special... Mathematical models for burden descending process have been applied to obtain whole burden structures in blast furnace,whereas the accuracy of those burden descent models has not been sufficiently investigated.Special evaluation method based on timeline burden profiles was established to quantitatively evaluate the error between experimental and modeled burden structures.Four existing burden descent models were utilized to describe the burden structure of a 1/20 scaled warm blast furnace.Input modeling conditions including initial burden profile,descending volumes in each time interval,and normalized descending velocity distribution were determined via special image processing technology.Modeled burden structures were evaluated combined with the published experimental data.It is found that all the models caught the main profile of the burden structure.Furthermore,the improved nonuniform descent model(Model IV)shows the highest level of precision especially when burden descends with unstable velocity distribution tendency.Meanwhile,the traditional nonuniform descent model(Model III)may also be desirable to model the burden descending process when the burden descending velocity presents a linear tendency.Finally,the uniform descent model(Model I)might be the first option for roughly predicting burden structure. 展开更多
关键词 burden descending descent normalized utilized scaled sufficiently modeled desirable quantitatively
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A modified three–term conjugate gradient method with sufficient descent property 被引量:1
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作者 Saman Babaie–Kafaki 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第3期263-272,共10页
A hybridization of the three–term conjugate gradient method proposed by Zhang et al. and the nonlinear conjugate gradient method proposed by Polak and Ribi`ere, and Polyak is suggested. Based on an eigenvalue analysi... A hybridization of the three–term conjugate gradient method proposed by Zhang et al. and the nonlinear conjugate gradient method proposed by Polak and Ribi`ere, and Polyak is suggested. Based on an eigenvalue analysis, it is shown that search directions of the proposed method satisfy the sufficient descent condition, independent of the line search and the objective function convexity. Global convergence of the method is established under an Armijo–type line search condition. Numerical experiments show practical efficiency of the proposed method. 展开更多
关键词 unconstrained optimization conjugate gradient method EIGENVALUE sufficient descent condition global convergence
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A gradually descent method for discrete global optimization 被引量:1
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作者 杨永建 张连生 《Journal of Shanghai University(English Edition)》 CAS 2007年第1期39-44,共6页
In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of fi... In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of finding one discrete minimizer of the objective function f to that of finding another at each cycle. The auxiliary function can ensure that a point, except a prescribed point, is not its integer stationary point if the value of objective function at the point is greater than the scalar which is chosen properly. This property leads to a better minimizer of f found more easily by some classical local search methods. The computational results show that this algorithm is quite efficient and reliable for solving nonlinear integer programming problems. 展开更多
关键词 gradually descent method nonlinear integer programming integer programming ALGORITHM
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Efficient multiuser detector based on box-constrained dichotomous coordinate descent and regularization 被引量:1
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作者 全智 刘杰 《Journal of Central South University》 SCIE EI CAS 2012年第6期1570-1576,共7页
The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated... The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated algorithm.The deregularization maximized the energy of the solution,which was opposite to the Tikhonov regularization where the energy was minimized.However,combined with box-constraints,the deregularization forced the solution to be close to the binary set.It further exploited the box-constrained dichotomous coordinate descent algorithm and adapted it to the nonstationary iterative Tikhonov regularization to present an efficient detector.As a result,the worst-case and average complexity are reduced down as K2.8 and K2.5 floating point operation per second,respectively.The development improves the "efficient frontier" in multiuser detection,which is illustrated by simulation results.In addition,most operations in the detector are additions and bit-shifts.This makes the proposed technique attractive for fixed-point hardware implementation. 展开更多
关键词 dichotomous coordinate descent de-regularization low complexity multiuser detection Tikhonov regularization
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Topological Uniform Descent and Judgement of A-Weyl's Theorem 被引量:1
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作者 SUN Chenhui WANG Ning CAO Xiaohong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第5期392-398,共7页
In this paper,a-Browder’s theorem and a-Weyl’s theorem for bounded linear operators are studied by means of the property of the topological uniform descent.The sufficient and necessary conditions for a bounded linea... In this paper,a-Browder’s theorem and a-Weyl’s theorem for bounded linear operators are studied by means of the property of the topological uniform descent.The sufficient and necessary conditions for a bounded linear operator defined on a Hilbert space holding aBrowder’s theorem and a-Weyl’s theorem are established.As a consequence of the main result,the new judgements of a-Browder’s theorem and a-Weyl’s theorem for operator function are discussed. 展开更多
关键词 a-Browder's theorem a-Weyl's theorem topological uniform descent
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Comparison of gait properties during level walking and stair ascent and descent with varying loads 被引量:1
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作者 Tomohiro Demura Shin-ich Demura Sohee Shin 《Health》 2010年第12期1372-1376,共5页
This study aimed to compare gait properties during level walking and during stair ascent and descent with varying loads. Fifteen healthy young men (mean age: 22.1 ± 1.6 years) walked while holding four different ... This study aimed to compare gait properties during level walking and during stair ascent and descent with varying loads. Fifteen healthy young men (mean age: 22.1 ± 1.6 years) walked while holding four different loads relative to each subject’s body mass (0, 20, 40 and 60% of body mass: BM) on their backs. Stance time, swing time, and double support times were selected as gait parameters. All parameters showed a maximal value during stair ascent and a minimum value during level walking. Stance and double support times increased significan- tly with each load during level walking and during stair ascent and descent. In conclusion, st- air ascent and descent creates more unstable movement than level walking regardless of the weight of the load. The effect of loads on gait increases with the weight of the load and becomes obvious once the load exceeds 60% of BM. 展开更多
关键词 GAIT STAIR ASCENT STAIR descent LOAD
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The Convergence of the Steepest Descent Algorithm for D.C.Optimization 被引量:1
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作者 SONG Chun-ling XIA Zun-quan 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期131-136,共6页
Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and c... Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and constrained quasi-differentiable programming is proved. 展开更多
关键词 nonsmooth optimization D. C. optimization upper semi-continuous lower semi-continuous steepest descent algorithm CONVERGENCE
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Temperature Prediction Model Identification Using Cyclic Coordinate Descent Based Linear Support Vector Regression 被引量:1
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作者 张堃 费敏锐 +1 位作者 吴建国 张培建 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期113-118,共6页
Temperature prediction plays an important role in ring die granulator control,which can influence the quantity and quality of production. Temperature prediction modeling is a complicated problem with its MIMO, nonline... Temperature prediction plays an important role in ring die granulator control,which can influence the quantity and quality of production. Temperature prediction modeling is a complicated problem with its MIMO, nonlinear, and large time-delay characteristics. Support vector machine( SVM) has been successfully based on small data. But its accuracy is not high,in contrast,if the number of data and dimension of feature increase,the training time of model will increase dramatically. In this paper,a linear SVM was applied combing with cyclic coordinate descent( CCD) to solving big data regression. It was mathematically strictly proved and validated by simulation. Meanwhile,real data were conducted to prove the linear SVM model's effect. Compared with other methods for big data in simulation, this algorithm has apparent advantage not only in fast modeling but also in high fitness. 展开更多
关键词 linear support vector machine(SVM) cyclic coordinates descent(CCD) optimization big data fast identification
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Global Convergence of an Extended Descent Algorithm without Line Search for Unconstrained Optimization 被引量:1
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作者 Cuiling Chen Liling Luo +1 位作者 Caihong Han Yu Chen 《Journal of Applied Mathematics and Physics》 2018年第1期130-137,共8页
In this paper, we extend a descent algorithm without line search for solving unconstrained optimization problems. Under mild conditions, its global convergence is established. Further, we generalize the search directi... In this paper, we extend a descent algorithm without line search for solving unconstrained optimization problems. Under mild conditions, its global convergence is established. Further, we generalize the search direction to more general form, and also obtain the global convergence of corresponding algorithm. The numerical results illustrate that the new algorithm is effective. 展开更多
关键词 UNCONSTRAINED Optimization descent Method Line SEARCH Global CONVERGENCE
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An Enhanced Steepest Descent Method for Global Optimization-Based Mesh Smoothing 被引量:1
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作者 Kang Zhao Yabang Ma +2 位作者 You Wang Xin Yin Yufei Guo 《Journal of Applied Mathematics and Physics》 2020年第11期2509-2518,共10页
<div style="text-align:justify;"> In order to speed up the global optimization-based mesh smoothing, an enhanced steepest descent method is presented in the paper. Numerical experiment results show tha... <div style="text-align:justify;"> In order to speed up the global optimization-based mesh smoothing, an enhanced steepest descent method is presented in the paper. Numerical experiment results show that the method performs better than the steepest descent method in the global smoothing. We also presented a physically-based interpretation to explain why the method works better than the steepest descent method. </div> 展开更多
关键词 MESH Mesh Smoothing Global Mesh Smoothing Optimization-Based Steepest descent Method
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PROJECTED GRADIENT DESCENT BASED ON SOFT THRESHOLDING IN MATRIX COMPLETION 被引量:1
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作者 Zhao Yujuan Zheng Baoyu Chen Shouning 《Journal of Electronics(China)》 2013年第6期517-524,共8页
Matrix completion is the extension of compressed sensing.In compressed sensing,we solve the underdetermined equations using sparsity prior of the unknown signals.However,in matrix completion,we solve the underdetermin... Matrix completion is the extension of compressed sensing.In compressed sensing,we solve the underdetermined equations using sparsity prior of the unknown signals.However,in matrix completion,we solve the underdetermined equations based on sparsity prior in singular values set of the unknown matrix,which also calls low-rank prior of the unknown matrix.This paper firstly introduces basic concept of matrix completion,analyses the matrix suitably used in matrix completion,and shows that such matrix should satisfy two conditions:low rank and incoherence property.Then the paper provides three reconstruction algorithms commonly used in matrix completion:singular value thresholding algorithm,singular value projection,and atomic decomposition for minimum rank approximation,puts forward their shortcoming to know the rank of original matrix.The Projected Gradient Descent based on Soft Thresholding(STPGD),proposed in this paper predicts the rank of unknown matrix using soft thresholding,and iteratives based on projected gradient descent,thus it could estimate the rank of unknown matrix exactly with low computational complexity,this is verified by numerical experiments.We also analyze the convergence and computational complexity of the STPGD algorithm,point out this algorithm is guaranteed to converge,and analyse the number of iterations needed to reach reconstruction error.Compared the computational complexity of the STPGD algorithm to other algorithms,we draw the conclusion that the STPGD algorithm not only reduces the computational complexity,but also improves the precision of the reconstruction solution. 展开更多
关键词 Matrix Completion (MC) Compressed Sensing (CS) Iterative thresholding algorithm Projected Gradient descent based on Soft Thresholding (STPGD)
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