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Tooth surface error correction of hypoid gears machined by duplex helical method 被引量:5
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作者 WU Shun-xing YAN Hong-zhi +3 位作者 WANG Zhi-yong BI Ren-gui CHEN Zhi ZHU Peng-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1402-1411,共10页
In this work,synchronous cutting of concave and convex surfaces was achieved using the duplex helical method for the hypoid gear,and the problem of tooth surface error correction was studied.First,the mathematical mod... In this work,synchronous cutting of concave and convex surfaces was achieved using the duplex helical method for the hypoid gear,and the problem of tooth surface error correction was studied.First,the mathematical model of the hypoid gears machined by the duplex helical method was established.Second,the coordinates of discrete points on the tooth surface were obtained by measurement center,and the normal errors of the discrete points were calculated.Third,a tooth surface error correction model is established,and the tooth surface error was corrected using the Levenberg-Marquard algorithm with trust region strategy and least square method.Finally,grinding experiments were carried out on the machining parameters obtained by Levenberg-Marquard algorithm with trust region strategy,which had a better effect on tooth surface error correction than the least square method.After the tooth surface error is corrected,the maximum absolute error is reduced from 30.9μm before correction to 6.8μm,the root mean square of the concave error is reduced from 15.1 to 2.1μm,the root mean square of the convex error is reduced from 10.8 to 1.8μm,and the sum of squared errors of the concave and convex surfaces was reduced from 15471 to 358μm^(2).It is verified that the Levenberg-Marquard algorithm with trust region strategy has a good accuracy for the tooth surface error correction of hypoid gear machined by duplex helical method. 展开更多
关键词 duplex helical method hypoid gear error measurement Levenberg–Marquard algorithm with trust region strategy correction of tooth surface error
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A Superlinerly Convergent ODE-type Trust Region Algorithm for LC^1 Optimization Problems 被引量:5
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作者 OUYi-gui HOUDing-pi 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期140-145,共6页
In this paper, a new trust region algorithm for unconstrained LC1 optimization problems is given. Compare with those existing trust regiion methods, this algorithm has a different feature: it obtains a stepsize at eac... In this paper, a new trust region algorithm for unconstrained LC1 optimization problems is given. Compare with those existing trust regiion methods, this algorithm has a different feature: it obtains a stepsize at each iteration not by soloving a quadratic subproblem with a trust region bound, but by solving a system of linear equations. Thus it reduces computational complexity and improves computation efficiency. It is proven that this algorithm is globally convergent and locally superlinear under some conditions. 展开更多
关键词 LC1 optimization ODE methods trust region algorithm superlinear convergence
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A Nonmonotone Trust Region Method for Solving Symmetric Nonlinear Equations 被引量:3
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作者 YUAN Gong-lin WEI Zeng-xin LU Xi-wen 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期574-584,共11页
A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical res... A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical results show that the method is interesting for the given problems. 展开更多
关键词 trust region method nonlinear equations nonmonotone technique
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Mobile robot path planning method combined improved artificial potential field with optimization algorithm 被引量:1
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作者 赵杰 Yu Zhenzhong Yan Jihong Gao Yongsheng Chen Zhifeng 《High Technology Letters》 EI CAS 2011年第2期160-165,共6页
To overcome the shortcomings of the traditional artificial potential field method in mobile robot path planning, an improved artificial potential field model (IAPFM) was established, then a new path planning method ... To overcome the shortcomings of the traditional artificial potential field method in mobile robot path planning, an improved artificial potential field model (IAPFM) was established, then a new path planning method combining the IAPFM with optimization algorithm (trust region algorithm) is proposed. Attractive force between the robot and the target location, and repulsive force between the robot and the obstacles are both converted to the potential field intensity; and filled potential field is used to guide the robot to go out of the local minimum points ; on this basis, the effect of dynamic obstacles velocity and the robot's velocity is consid thers and the IAPFM is established, then both the expressions of the attractive potential field and the repulsive potential field are obtained. The trust region algorithm is used to search the minimum value of the sum of all the potential field inten- sities within the movement scope which the robot can arrive in a sampling period. Connecting of all the points which hare the minimum intensity in every sampling period constitutes the global optimization path. Experiment result shows that the method can meet the real-time requirement, and is able to execute the mobile robot path planning task effectively in the dynamic environment. 展开更多
关键词 trust region optimization algorithm path planning artificial potential field mobile robot potential field intensity
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A framework for quantifying properties of 3-dimensional movement-based signals 被引量:2
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作者 Shaun TD NEW Richard A PETERS 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期327-336,共10页
Understanding how signal properties are optimized for the reliable transmission of information requires accurate de- scription of the signal in time and space. For movement-based signals where movement is restricted t... Understanding how signal properties are optimized for the reliable transmission of information requires accurate de- scription of the signal in time and space. For movement-based signals where movement is restricted to a single plane, measure- ments from a single viewpoint can be used to consider a range of viewing positions based on simple geometric calculations. However, considerations of signal properties from a range of viewing positions for movements extending into three-dimensions (3D) are more problematic. We present here a new framework that overcomes this limitation, and enables us to quantify the extent to which movement-based signals are view-specific. To illustrate its application, a Jacky lizard tail flick signal was filmed with synchronized cameras and the position of the tail tip digitized for both recordings. Camera aligmnent enabled tl^e construction of a 3D display action pattern profile. We analyzed the profile directly and used it to create a detailed 3D animation. In the virtual environment, we were able to film the same signal from multiple viewing positions and using a computational motion analysis algorithm (gradient detector model) to measure local image velocity in order to predict view dependent differences in signal properties. This approach will enable consideration of a range of questions concerning movement-based signal design and evolu- tion that were previously out of reach [Current Zoology 56 (3): 327-336, 2010]. 展开更多
关键词 Signal evolution Sensory Ecology Movement-based signal 3D Display Action Pattern
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Endocytosis of adiponectin receptor I through a clathrin- and Rab5-dependent pathway 被引量:4
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作者 Qiurong Ding Zhenzhen Wang Yan Chen 《Cell Research》 SCIE CAS CSCD 2009年第3期317-327,共11页
In eukaryotic cells, receptor endocytosis is a key event regulating signaling transduction. Adiponectin receptors belong to a new receptor family that is distinct from G-protein-coupled receptors and has critical role... In eukaryotic cells, receptor endocytosis is a key event regulating signaling transduction. Adiponectin receptors belong to a new receptor family that is distinct from G-protein-coupled receptors and has critical roles in the pathogenesis of diabetes and metabolic syndrome. Here, we analyzed the endocytosis of adiponectin and adiponectin receptor 1 (AdipoR1) and found that they are both internalized into transferrin-positive compartments that follow similar traffic routes. Blocking clathrin-mediated endocytosis by expressing Eps15 mutants or depleting K^+ trapped AdipoR1 at the plasma membrane, and K^+ depletion abolished adiponectin internalization, indicating that the endocytosis of AdipoR1 and adiponectin is clathrin-dependent. Depletion of K^+ and overexpression of Eps15 mutants enhance adiponectin- stimulated AMP-activated protein kinase phosphorylation, suggesting that the endocytosis of AdipoR1 might down-regulate adiponectin signaling. In addition, AdipoR1 colocalizes with the small GTPase Rab5, and a dominant negative Rab5 abrogates AdipoR1 endocytosis. These data indicate that AdipoR1 is internalized through a clathrin- and Rab5- dependent pathway and that endocytosis may play a role in the regulation of adiponectin signaling. 展开更多
关键词 ADIPONECTIN adiponectin receptors CLATHRIN ENDOCYTOSIS Rab5
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DVD CD
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《新潮电子》 2007年第6期138-139,共2页
《信赖铃音-肖邦之梦》;《鬼泣4》;《破绽》;《热血警探/终棘警探》;《疯羊》;
关键词 DVD CD 《信赖铃音-肖邦之梦》 《鬼泣4》 《破绽》 《疯羊》
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TRAIL receptor mediates inflammatory cytokine release in an NF-κB-dependent manner 被引量:14
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作者 Wanhu Tang Weimin Wang Yaxi Zhang Shilian Liu Yanxin Liu Dexian Zheng 《Cell Research》 SCIE CAS CSCD 2009年第6期758-767,共10页
In the present article, we report that DR4 or DR5 overexpression dramatically activates the release of the inflammatory cytokines IL-8, TNF-α, CCL20, MIP-2 and MIP-1β in an NF-κB-dependent manner in 293T, MDA-MB-23... In the present article, we report that DR4 or DR5 overexpression dramatically activates the release of the inflammatory cytokines IL-8, TNF-α, CCL20, MIP-2 and MIP-1β in an NF-κB-dependent manner in 293T, MDA-MB-231 and HCT-116 cells. We showed that death receptor-mediated signals were extracellular domain-independent, whereas the effect of overexpression of the DR4 intracellular domain was much less potent. The TRADD-TRAF2-NIK- IKKα/β signaling cascade, which plays an essential role in TNF-induced NF-κB activation, was found to be involved in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-mediated signal transduction. The FADD-caspase signaling pathway, which has been reported to be mostly related to apoptosis, was identified as being essential for DR4 or DR5 overexpression-mediated NF-κB activation and cytokine secretion and crosstalks with the TRADD-TRAF2-NIK-IKKα/β signaling cascade. Furthermore, a DR5 agonistic antibody (AD5-10) triggered the inflammatory cytokine release. These data, together with previous reports, provide strong evidence that TRAIL and TRAIL receptors play an important role in inflammation. 展开更多
关键词 TRAIL receptor INFLAMMATION CYTOKINE NF-ΚB
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System Design Of Security Evaluation For Data Link Communications
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作者 Feng Haixun ZangYong 《International Journal of Technology Management》 2014年第7期46-47,共2页
Data link communication requires data communication process must have reliability, availability, confidentiality, availability, integrity, non-repudiation, controllability.This has a great effect to ensure the normal ... Data link communication requires data communication process must have reliability, availability, confidentiality, availability, integrity, non-repudiation, controllability.This has a great effect to ensure the normal communication functions.In this paper the author on the basis of many years of work experience, first discussed the establishment of a risk assessment system data link,then focused on the problem of index weight assessment.To data communication security, this research article will provide some references. 展开更多
关键词 Data link Communications security AHP
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Second-Order Consensus of Multiple Agents with Coupling Delay 被引量:5
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作者 SU Hou-Sheng ZHANG Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期101-109,共9页
In this paper, we investigate two kinds of second-order consensus algorithms for multiple agents with coupling delay under general fixed directed information topology. Stability analysis is performed based on Lyapunov... In this paper, we investigate two kinds of second-order consensus algorithms for multiple agents with coupling delay under general fixed directed information topology. Stability analysis is performed based on Lyapunov- Krasovskii functional method. Delay-dependent asymptotical stability condition in terms of linear matrix inequalities (LMIs) is derived for the second-order consensus algorithm of delayed dynamical networks. Both delay-independent and delay-dependent asymptotical stability conditions in terms of LMIs are derived for the second-order consensus algorithm with information feedback. 展开更多
关键词 CONSENSUS time delay linear matrix inequality multi-agent systems
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Proline-rich tyrosine kinase 2 and its inhibitor PRNK 被引量:1
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作者 Hao Jia Guo Hong You Kai Xiao Yinbing 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第5期307-312,共6页
Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulat... Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK. 展开更多
关键词 Proline-rich tyrosine kinase 2 Pyk2 related non-kinase Dominant negative
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信赖
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作者 孙道荣 《做人与处世》 2010年第12期40-40,共1页
黄昏,几个男孩子,在小区的草地上玩耍.不时听到他们快乐的叫声。 一个胖胖的男孩,拘谨地站在一边,他们不带他玩,因为他是“傻子”有时候.他们的球踢到路那头了,他们就喊他:“傻子,去帮我们把球捡回来。”
关键词 《信赖》 小说 文学 孙道荣
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信赖
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作者 佚名 《芝麻开门(益智阅读)》 2011年第7期21-21,共1页
信赖是孩子遭惊怕时要寻找的母亲的怀抱,是妻子受委屈时想依偎的丈夫的臂膀,是你我有心事时欲倾吐的朋友的小屋。
关键词 小学 课外阅读 阅读材料 《信赖》
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信赖能创造美好境界
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作者 赵昱 《小主人报》 2010年第4期15-15,共1页
生活中快乐的事情有很多,如有好吃的、好玩的、去游乐场、得到老师韵表扬等,但我觉得被信任的喜悦是最美好的。我听到过这样一句话:“信赖往往创造出美好的境界”。这句话让我懂得,人一定要信赖别人,信任可以搭建起友谊的桥梁。
关键词 小学 作文 语文教学 《信赖能创造美好境界》
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Optimality Condition for Infinite-dimensional Programming Problem with Operator and Bound Constraints
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作者 李春发 冯恩民 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2004年第2期257-266,共10页
A first-order necessary condition for an infinite-dimensional nonlinear op-timization problem, which arises when the all-at-once method is employed to slove theoptimal control problems, is formulated and analyzed. Ope... A first-order necessary condition for an infinite-dimensional nonlinear op-timization problem, which arises when the all-at-once method is employed to slove theoptimal control problems, is formulated and analyzed. Operator constraint and simplebound on part of the variables are both considered. Based on this optimality condition,the trust-region subproblems are built, then the trust region method rnay be employedto deal with the optimizatiou problem in infinite-dimensional space. 展开更多
关键词 optimal control operator constraint trust-region method
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A Trust-region Algorithm for Nonlinear Constrained Optimization Problem
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作者 童小娇 周叔子 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2004年第3期445-460,共16页
This paper presents a new trust-region algorithm for general nonlinear constrained optimization problems. Certain equivalent KKT conditions of the problems are derived. Global convergence of the algorithm to a first-o... This paper presents a new trust-region algorithm for general nonlinear constrained optimization problems. Certain equivalent KKT conditions of the problems are derived. Global convergence of the algorithm to a first-order KKT point is established under mild conditions on the trial steps. Numerical example is also reported. 展开更多
关键词 nonlinear constrained optimization trust-region method global convergence.
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Curvilinear Paths with Nonmonotonic Inexact Line Search Technique for Unconstrained Optimization
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作者 朱德通 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2004年第4期627-648,共22页
In this paper we modify approximate trust region methods via three precon ditional curvilinear paths for unconstrained optimization. To easily form preconditional curvilinear paths within the trust region subproblem, ... In this paper we modify approximate trust region methods via three precon ditional curvilinear paths for unconstrained optimization. To easily form preconditional curvilinear paths within the trust region subproblem, we employ the stable Bunch-Parlett factorization method of symmetric matrices and use the unit lower triangular matrix as a preconditioner of the optimal path and modified gradient path. In order to accelerate the preconditional conjugate gradient path, we use preconditioner to improve the eigenvalue distribution of Hessian matrix. Based on the trial steps produced by the trust region subproblem along the three curvilinear paths providing a direction of sufficient descent, we mix a strategy using both trust region and nonmonotonic line search techniques which switch to back tracking steps when a trial step is unacceptable. Theoretical analysis is given to prove that the proposed algorithms are globally convergent and have a local su-pcrlinear convergent rate under some reasonable conditions. The results of the numerical experiment are reported to show the effectiveness of the proposed algorithms. 展开更多
关键词 Curvilinear paths preconditioned trust region methods nonmonotonic technique.
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An improved trust region method for unconstrained optimization 被引量:5
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作者 ZHOU QingHua ZHANG YaRui +2 位作者 XU FengXia GENG Yan SUN XiaoDian 《Science China Mathematics》 SCIE 2013年第2期425-434,共10页
In this paper,we propose an improved trust region method for solving unconstrained optimization problems.Different with traditional trust region methods,our algorithm does not resolve the subproblem within the trust r... In this paper,we propose an improved trust region method for solving unconstrained optimization problems.Different with traditional trust region methods,our algorithm does not resolve the subproblem within the trust region centered at the current iteration point,but within an improved one centered at some point located in the direction of the negative gradient,while the current iteration point is on the boundary set.We prove the global convergence properties of the new improved trust region algorithm and give the computational results which demonstrate the effectiveness of our algorithm. 展开更多
关键词 unconstrained optimization trust region methods global convergence negative gradient direction ITERATIVE
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AN AFFINE SCALING DERIVATIVE-FREE TRUST REGION METHOD WITH INTERIOR BACKTRACKING TECHNIQUE FOR BOUNDED-CONSTRAINED NONLINEAR PROGRAMMING 被引量:1
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作者 GAO Jing ZHU Detong 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第3期537-564,共28页
This paper proposes an arlene scaling derivative-free trust region method with interior backtracking technique for bounded-constrained nonlinear programming. This method is designed to get a stationary point for such ... This paper proposes an arlene scaling derivative-free trust region method with interior backtracking technique for bounded-constrained nonlinear programming. This method is designed to get a stationary point for such a problem with polynomial interpolation models instead of the objective function in trust region subproblem. Combined with both trust region strategy and line search technique, at each iteration, the affine scaling derivative-free trust region subproblem generates a backtracking direction in order to obtain a new accepted interior feasible step. Global convergence and fast local convergence properties are established under some reasonable conditions. Some numerical results are also given to show the effectiveness of the proposed algorithm. 展开更多
关键词 Affine scaling backtracking technique box constrains derivative-free optimization non-linear programming trust region method.
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A necessary and sufficient condition of convexity for SOC reformulation of trust-region subproblem with two intersecting cuts 被引量:2
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作者 YUAN JianHua WANG MeiLing +1 位作者 AI WenBao SHUAI TianPing 《Science China Mathematics》 SCIE CSCD 2016年第6期1127-1140,共14页
We consider the extended trust-region subproblem with two linear inequalities. In the "nonintersecting" case of this problem, Burer and Yang(2015) have proved that its semi-definite programming relaxation wi... We consider the extended trust-region subproblem with two linear inequalities. In the "nonintersecting" case of this problem, Burer and Yang(2015) have proved that its semi-definite programming relaxation with second-order-cone reformulation(SDPR-SOCR) is a tight relaxation. In the more complicated "intersecting" case, which is discussed in this paper, so far there is no result except for a counterexample for the SDPR-SOCR. We present a necessary and sufficient condition for the SDPR-SOCR to be a tight relaxation in both the "nonintersecting" and "intersecting" cases. As an application of this condition, it is verified easily that the "nonintersecting" SDPR-SOCR is a tight relaxation indeed. Furthermore, as another application of the condition, we prove that there exist at least three regions among the four regions in the trust-region ball divided by the two intersecting linear cuts, on which the SDPR-SOCR must be a tight relaxation. Finally, the results of numerical experiments show that the SDPR-SOCR can work efficiently in decreasing or even eliminating the duality gap of the nonconvex extended trust-region subproblem with two intersecting linear inequalities indeed. 展开更多
关键词 trust-region subproblem linear inequality constraints global solutions second-order-cone refor-mulation SDP relaxation
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