关键词： 异构网络   数据缓冲区   替换算法   数学建模   缓冲区  

摘要： 针对异构网络数据的缓冲存储效率低、分区存储精准度、运行代价高等问题,提出异构网络数据缓冲区替换算法的数学模型。首先将异构网络数据划分为多个数据阶层,确定数据格式,同时利用新的异构网络数据传输途径控制传输链路,对控制算法的窗口大小进行计算,以此梳理数据。最后将缓冲区分为冷区与热区两部分,分析算法的干扰因素,利用交替算法完成异构网络数据缓冲区替换算法的数学建模。仿真结果表明,基于异构网络数据缓冲区替换算法的数学模型可以有效提升算法的效率和精准度,同时可以降低算法运行代价。

关键词： 编程加工   数控编程   数控机床加工   数学算法   断刀   刻字   结合运用  

摘要： 所谓骗刀法,就是编程刀具和实际在数控机床加工时的刀具不一致的情况。以下对骗刀法在数控编程与数控机床中结合运用进行了深入探讨和论述,主要对刻字、雕花加工时骗刀法的合理使用,进行了深入详细的探讨和论述。得出采用骗刀法可有效解决在刻字时出现刀路断续和不完整情况,同时可避免断刀,且大大提高编程加工效率;解决了在雕花中用骗刀法灵活处理不同类型刀具的编程加工。总之,CAM数控编程软件数学算法无法解决的上述问题,通过骗刀法得以合理有效解决,并使数控编程加工高效顺利进行,合格地加工出零件。

关键词： 图像处理   STM图像   数学形态学   阈值分割  

摘要： 高温扫描隧道显微镜(HT-STM)可以实时原位地捕捉到表面原子的熔化相变过程.在这一原位变温实验中,快速可靠地识别出每帧STM图像中的熔融相十分关键.传统的手工统计方法存在效率低下、随意性大等问题.我们发展出一套基于数学形态学的算法,来自动快速地识别.与人工方法相比,该算法消除了人为主观误差,使确定的边界更加准确、光滑,处理效率提高了266倍.

关键词： 计算机科学   计算机数学   数学应用   深度融合   数值分析   数学与计算机   高等数学   辅助作用  

摘要： 随着计算机科学的快速发展,数学与计算机在数值分析领域得到了十分广泛的应用,对于高等数学的数值计算与分析有着重要的辅助作用,促进现代数学应用的深度发展。如何推动数学与计算机技术的深度融合,使其在数值分析领域发挥“1+1>2”的功效,是当前计算机数学研究领域的重要议题。

关键词： 小学数学   多样化计算   优化算法  

摘要： 小学数学教学中倡导算法多样化的教学理念.教师在数学教学中融入多样化的算法,不仅能培养学生的基础运算能力,而且能让学生形成解题思维,让学生体会到解决数学问题的多样性,从而锻炼学生的逻辑思维能力,培养学生的创新精神.在小学数学多样化计算教学中优化算法代表了计算教学的改革,实现了让学生成为课堂主体的目标,让学生在课堂中进行思考.本文主要讲述了在小学数学多样化计算教学中优化算法的具体策略,希望为数学教师提升数学课堂的教学质量提供帮助.

关键词： 上下文因素   参数学习   兴趣点推荐算法   融合方法  

摘要： 基于位置的社交网络的快速发展,通过借助社交网络来分享用户位置信息,其中包含了丰富的上下文信息,比如用户签到、兴趣点地理位置、用户社交关系等,从而对兴趣点推荐的发展提供了很大的机遇。但是,如何有效地利用这些上下文信息,解决数据稀疏和隐式反馈等问题,是很大的挑战。针对这一问题,提出了一种能够动态融合不同上下文因素的推荐算法,该推荐算法可以融合不同类型的上下文因素,比如地理信息、类别信息、时间信息等,通过一种类似梯度下降的动态权重参数学习的方法,动态地学习每个因素的权重,适应不同类型用户特点,从而改善兴趣点推荐效果。

关键词： Geometric algebra   Adaptive filtering   M-estimate   Multidimensional signal processing   Variable step-size  

摘要： In this paper, the transient performance of the geometric algebra based least mean M-estimate (GA-LMM) filtering algorithm is analyzed in detail under some simplifying assumptions. Further, the variable step-size variant VSS-GA-LMM is designed to eliminate the constraint of the constant step size on the per-formance of the GA-LMM and the optimal step size is obtained by maximizing the difference of mean square deviation (MSD) between successive iterations, which effectively balances the contradiction be-tween convergence rate and steady-state error. Finally, numerical simulations are presented to verify the validity of the theoretical analysis of the GA-LMM and the advantages of the GA-LMM and VSS-GA-LMM algorithms. (c) 2021 Elsevier B.V. All rights reserved.

关键词： 小学数学   算法优化   多样化   思考  

摘要： 小学阶段属于我国义务教学的重要阶段,也是小学生奠定学科基础的重要阶段,在素质教育的理念影响下,小学的教学不仅需要教授学生学科的基础知识,同时还需要培养小学生的学科综合素养,本文以小学数学教学为陈述对象,通过对小学数学算法多样化的分析,进一步分析如何优化小学数学算法,以此来提高小学生的数学学习能力以及计算能力,同时也锻炼小学生的数学思维,培养小学生的逻辑思维能力等,进而培养小学生的数学核心素养。因此在本篇文章当中首先陈述了进行小学数学算法多样化以及优化的价值,然后提出有效的策略来进行小学数学算法优化以及多样化,希望给予教育工作者以借鉴。

关键词： Preprojective algebra   Deformed preprojective algebra   Self-injective algebra   Periodic algebra   System of equations  

摘要： We construct a numeric algorithm for completing the proof of a conjecture asserting that all deformed preprojective algebras of generalized Dynkin type are periodic. In particular, we obtain an algorithmic procedure showing that non-trivial deformed preprojective algebras of Dynkin types E-7 and E-8 exist only in characteristic 2. As a consequence, we show that deformed preprojective algebras of Dynkin types E-6, E-7 and E-8 are periodic and we obtain an algorithm for a classification of such algebras, up to algebra isomorphism. We do it by a reduction of the conjecture to a solution of a system of equations associated with the problem of the existence of a suitable algebra isomorphism. phi(f): P-f (E-n) -> P(E-n) described in Theorem 2.1. One also shows that our algorithmic approach to the conjecture is also applicable to the classification of the mesh algebras of generalized Dynkin type. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Assembly   Job shop   Branch and bound   Scheduling   Two-stage production system  

摘要： Purpose Two-stage production systems including a processing shop and an assembly stage are widely used in various manufacturing industries. These two stages are usually studied independently which may not lead to ideal results. This paper aims to deal with a two-stage production system including a job shop and an assembly stage. Design/methodology/approach Some exact methods are proposed based on branch and bound (B&B) approach to minimize the total completion time of products. As B&B approaches are usually time-consuming, three efficient lower bounds are developed for the problem and variable neighborhood search is used to provide proper upper bound of the solution in each branch. In addition, to create branches and search new nodes, two strategies are applied including the best-first search and the depth-first search (DFS). Another feature of the proposed algorithms is that the search space is reduced by releasing the precedence constraint. In this case, the problem becomes equivalent to a parallel machine scheduling problem, and the redundant branches that do not consider the precedence constraint are removed. Therefore, the number of nodes and computational time are significantly reduced without eliminating the optimal solution. Findings Some numerical examples are used to evaluate the performance of the proposed methods. Comparison result to mathematical model (mixed-integer linear programming) validates the performance accuracy and efficiency of the proposed methods. In addition, computational results indicate the superiority of the DFS strategy with regard to CPU time. Originality/value Studies about the scheduling problems for two-stage production systems including job shop followed by an assembly stage traditionally present approximate method and metaheuristic algorithms to solve the problem. This is the first study that introduces exact methods based on (B&B) approach.