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A GENERALIZED SCALAR AUXILIARY VARIABLE METHOD FOR THE TIME-DEPENDENT GINZBURG-LANDAU EQUATIONS
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作者 司智勇 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期650-670,共21页
This paper develops a generalized scalar auxiliary variable(SAV)method for the time-dependent Ginzburg-Landau equations.The backward Euler method is used for discretizing the temporal derivative of the time-dependent ... This paper develops a generalized scalar auxiliary variable(SAV)method for the time-dependent Ginzburg-Landau equations.The backward Euler method is used for discretizing the temporal derivative of the time-dependent Ginzburg-Landau equations.In this method,the system is decoupled and linearized to avoid solving the non-linear equation at each step.The theoretical analysis proves that the generalized SAV method can preserve the maximum bound principle and energy stability,and this is confirmed by the numerical result,and also shows that the numerical algorithm is stable. 展开更多
关键词 time-dependent Ginzburg-Landau equation generalized scalar auxiliary variable algorithm maximum bound principle energy stability
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Reconsidering “Does the Sum Rule Hold at the Big Bang?” with Pre Planckian HUP, and Division Algebras 被引量:1
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作者 Andrew W. Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期539-557,共19页
In 2012, the author submitted an article to the Prespacetime Journal based upon the premise of inquiry as to the alleged vanishing of disjoint open sets contributing to quantum vector measures no longer working, i.e. ... In 2012, the author submitted an article to the Prespacetime Journal based upon the premise of inquiry as to the alleged vanishing of disjoint open sets contributing to quantum vector measures no longer working, i.e. the solution in 2012 was that the author stated that quantum measures in 4 dimensions would not work, mandating, if measure theory were used, imbedding in higher dimensions was necessary for a singularity. The idea was to use the methodology of String Theory as to come up with a way out of the impasse if higher dimensions do not exist. We revisit this question, taking into account a derived HUP, for metric tensors if we look at Pre-Planckian space-time introducing a pre-quantum mechanical HUP which may be a way to ascertain a solution not mandating higher dimensions, as well as introducing cautions as to what will disrupt the offered solution. Note that first, measurable spaces allow disjoint sets. Also, that smooth relations alone do not define separability or admit sets Planck’s length, if it exists, is a natural way to get about the “bad effects” of a cosmic singularity at the beginning of space-time evolution, but if a development is to be believed, namely by Stoica in the article, about removing the cosmic singularity as a breakdown point in relativity, there is nothing which forbids space-time from collapsing to a point. Without the use of a Pre Planckian HUP, for metric tensors, the quantum measures in four dimensions break down. We try to ascertain if a Pre Planckian HUP is sufficient to avoid this pathology and also look at if division algebras which can link Octonionic geometry and E8, to Quark spinors, in the standard model and add sufficient definition to the standard model are necessary and sufficient conditions for a metric tensor HUP which may remove this breakdown of the sum rule in the onset of the “Big Bang”. 展开更多
关键词 Quantum Measures Spatial DIFFEOMORPHISM Cylinder SETS Caratheodary-Hahn-Huvanek theorem Big Bang Singularity Causal SETS Modified PRE Planckian HEISENBERG Uncertainty Principle HUP division ALGEBRAS
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针对OFDM的低轨卫星资源动态分配算法
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作者 张美蓉 张晨 张更新 《太赫兹科学与电子信息学报》 2024年第9期992-999,共8页
在天地一体化信息网络场景下,卫星通信与地面5G的融合是大势所趋。因此,正交频分复用(OFDM)作为5G空口协议的关键技术,如何高效服务于频带资源受限的低轨卫星通信系统成为研究热点。针对低轨卫星高动态性、系统信道特征、业务时变性以... 在天地一体化信息网络场景下,卫星通信与地面5G的融合是大势所趋。因此,正交频分复用(OFDM)作为5G空口协议的关键技术,如何高效服务于频带资源受限的低轨卫星通信系统成为研究热点。针对低轨卫星高动态性、系统信道特征、业务时变性以及大多普勒频移等特点,提出一种针对OFDM的低轨卫星资源动态分配策略。首先根据3GPP标准规定和最大化频谱效率选择载波间隔,子载波分配前通过剔除劣子信道保证信道的传输性能,通过分簇成倍级减少分配时的循环次数;随后依据用户需求及信道特征对子载波进行贪婪分配;最后对单用户按照比例所分到的功率应用注水原理。仿真结果表明,该算法能有效适应低轨卫星场景,降低算法的复杂度,提高系统容量的同时仍可保证用户需求与传输速率的公平性。 展开更多
关键词 低轨卫星 正交频分复用 多普勒频移 贪婪算法 注水原理
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EXISTENCE AND ALGORITHM OF SOLUTIONS FOR GENERAL MULTIVALUED MIXED IMPLICIT QUASI-VARIATIONAL INEQUALITIES
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作者 曾六川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1324-1333,共10页
A new class of general multivalued mixed implicit quasi-variational inequalities in a real Hilbert space was introduced, which includes the known class of generalized mixed implicit quasi-variational inequalities as a... A new class of general multivalued mixed implicit quasi-variational inequalities in a real Hilbert space was introduced, which includes the known class of generalized mixed implicit quasi-variational inequalities as a special case , introduced and studied by Ding Xie-ping . The auxiliary variational principle technique was applied to solve this class of general multivalued mixed implicit quasi-variational inequalities. Firstly, a new auxiliary variational inequality with a proper convex , lower semicontinuous , binary functional was defined and a suitable functional was chosen so that its unique minimum point is equivalent to the solution of such an auxiliary variational inequality . Secondly , this auxiliary variational inequality was utilized to construct a new iterative algorithm for computing approximate solutions to general multivalued mixed implicit quasi-variational inequalities . Here , the equivalence guarantees that the algorithm can generate a sequence of approximate solutions. Finally, the existence of solutions and convergence of approximate solutions for general multivalued mixed implicit quasi-variational inequalities are proved. Moreover, the new convergerce criteria for the algorithm were provided. Therefore, the results give an affirmative answer to the open question raised by M. A . Noor, and extend and improve the earlier and recent results for various variational inequalities and complementarity problems including the corresponding results for mixed variational inequalities, mixed quasi-variational inequalities and quasi-complementarity problems involving the single-valued and set- valued mappings in the recent literature . 展开更多
关键词 general multivalued mixed implicit quasi-variational inequality auxiliary variational principle technique EXISTENCE algorithm
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Auxiliary principle and approximation solvability for system of new generalized mixed equilibrium problems in reflexive Banach spaces
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期231-240,共10页
A new system of generalized mixed equilibrium problems (SGMEPs) involving generalized mixed variational-like inequality problems is introduced and studied in reflexive Banach spaces. A system of auxiliary generalize... A new system of generalized mixed equilibrium problems (SGMEPs) involving generalized mixed variational-like inequality problems is introduced and studied in reflexive Banach spaces. A system of auxiliary generalized mixed equilibrium problems (SAGMEPs) for solving the SGMEPs is first introduced. Existence and uniqueness of the solutions to the SAGMEPs is proved under quite mild assumptions without any coercive conditions in reflexive Banach spaces. Using the auxiliary principle technique, a new iterative algorithm for solving the SGMEPs is proposed and analyzed. Strong convergence of the iterative sequences generated by the algorithm is also proved under quite mild assumptions without any coercive conditions. These results improve, unify, and generalize some recent results in this field. 展开更多
关键词 system of generalized mixed equilibrium problem auxiliary principle iterative algorithm reflexive Banach space
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Existence and Algorithm of Solutions for Generalized Mixed Implicit Quasi-Variational-Like Inequalities
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作者 胡润雪 张勇 张红龄 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期87-91,共5页
By applying the auxiliary variational principle technique, the existence of solutions for a new class of generalized mixed implicit quasi-variational-like inequalities and the convergence criteria of a new iterative a... By applying the auxiliary variational principle technique, the existence of solutions for a new class of generalized mixed implicit quasi-variational-like inequalities and the convergence criteria of a new iterative algorithm to compute approximate solutions are proved in Hilbert spaces. The obtained result is a improvement over and generalization of the main theorem proposed by Ding. 展开更多
关键词 Generalized mixed implicit quasi-variational-like inequality Auxiliary principle technique Gap function Iterative algorithm
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STUDY ON EFFICIENT COMPUTATION AND PERFORMANCE OF AV-BASED REDUCED-RANK FILTERING
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作者 XuBin YangChenyang MaoShiyi 《Journal of Electronics(China)》 2005年第2期153-160,共8页
In this paper, the complexity and performance of the Auxiliary Vector (AV) based reduced-rank filtering are addressed. The AV filters presented in the previous papers have the general form of the sum of the signature ... In this paper, the complexity and performance of the Auxiliary Vector (AV) based reduced-rank filtering are addressed. The AV filters presented in the previous papers have the general form of the sum of the signature vector of the desired signal and a set of weighted AVs,which can be classified as three categories according to the orthogonality of their AVs and the optimality of the weight coefficients of the AVs. The AV filter with orthogonal AVs and optimal weight coefficients has the best performance, but requires considerable computational complexity and suffers from the numerical unstable operation. In order to reduce its computational load while keeping the superior performance, several low complexity algorithms are proposed to efficiently calculate the AVs and their weight coefficients. The diagonal loading technique is also introduced to solve the numerical unstability problem without complexity increase. The performance of the three types of AV filters is also compared through their application to Direct Sequence Code Division Multiple Access (DS-CDM A) systems for interference suppression. 展开更多
关键词 Reduced-rank filtering Auxiliary Vector(AV) Efficient computation Direct Sequence Code division Multiple Access(DS-CDMA) Interference suppression
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新时代我国行政区划的制度设计、目标指向与优化策略 被引量:1
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作者 赵聚军 《新疆师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第3期125-136,F0002,共13页
新时代在完善优化行政区划制度设计过程中,坚持发展与治理并重的新理念是认识前提,加强党对行政区划工作的集中统一领导是根本保障,持续推动法治建设是关键支撑,健全论证评估机制与方法是基本路径。在目标导向方面,应重点关注三项新课题... 新时代在完善优化行政区划制度设计过程中,坚持发展与治理并重的新理念是认识前提,加强党对行政区划工作的集中统一领导是根本保障,持续推动法治建设是关键支撑,健全论证评估机制与方法是基本路径。在目标导向方面,应重点关注三项新课题:以优化基层行政区划为主要着力点,提升超大特大城市的资源承载能力;通过优化乡镇行政区划设置,推动以县城为重要载体的新型城镇化;通过优化收缩型城市和“小县”的行政区划设置,助推区域协同高质量发展。作为完成上述目标的保障机制,要在充分发挥党的全面领导、协调各方作用基础上强化党政部门协同,在明确价值导向前提下健全论证与评估体系,系统总结我国行政区划设置的历史经验,提升调整方案的明确性,减少调整的“后遗症”。 展开更多
关键词 行政区划 指导理念 决策体制 论证评估 法治建设
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抽水蓄能电站厂用电系统备自投设计及实现
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作者 司青花 宁翰 马力 《水电与新能源》 2024年第9期9-12,共4页
大中型水电站厂用电系统接线复杂,备自投动作逻辑也不简单,同时还需考虑两级备自投之间的动作配合。针对某抽水蓄能电站10 kV及0.4 kV厂用电系统备自投的设计原则、动作逻辑等方面开展了研究,提出两级厂用电系统备自投间的定值及动作时... 大中型水电站厂用电系统接线复杂,备自投动作逻辑也不简单,同时还需考虑两级备自投之间的动作配合。针对某抽水蓄能电站10 kV及0.4 kV厂用电系统备自投的设计原则、动作逻辑等方面开展了研究,提出两级厂用电系统备自投间的定值及动作时间配合方案,可以保证电站厂用电系统的安全可靠运行。 展开更多
关键词 抽水蓄能电站 厂用电系统 备自投 设计原则 动作逻辑
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适用2000 HSC CODE的高速船特点及总体设计要求
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作者 张伟 曲宁宁 段玉龙 《船舶》 2024年第3期60-67,共8页
高速船由于其航速高、质量轻、营运特殊等特点,需要适用的规则与常规船型不同。2000年的《国际高速船安全规则》(简称2000 HSC CODE)作为较完备的适用于高速船的规则,被各海事主管机关广泛接受作为高速船的设计依据。文中简要介绍2000 H... 高速船由于其航速高、质量轻、营运特殊等特点,需要适用的规则与常规船型不同。2000年的《国际高速船安全规则》(简称2000 HSC CODE)作为较完备的适用于高速船的规则,被各海事主管机关广泛接受作为高速船的设计依据。文中简要介绍2000 HSC CODE的安全原理,以及该规则对各海事主管机关的适用程度;然后通过国内外高速船事故来分析该类船的事故类型及致因特点,并进一步介绍了适用高速船的风险控制及设计措施,包括营运限制、破舱稳性、防火要求和撤离分析等总体设计要求,以供理解高速船的安全原理并指导其设计。 展开更多
关键词 国际高速船安全规则 安全原理 高速船事故 营运限制 船底破损 阻火分隔
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二维非线性耦合复Ginzburg-Landau方程组的周期波解 被引量:1
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作者 陈兆蕙 李泽华 《宝鸡文理学院学报(自然科学版)》 CAS 2011年第2期6-10,共5页
目的研究一类二维非线性耦合复Ginzburg-Landau方程组。方法采用齐次平衡原理和辅助函数方法。结果与结论得到了此类方程组的周期波解。
关键词 Ginzburg-Landau耦合方程组 周期波解 辅助函数方法 齐次平衡原理
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辅助站立坐便器设计与试验
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作者 郭家伟 赵民 +1 位作者 王佐 王小甜 《机械设计与制造》 北大核心 2024年第4期95-99,共5页
针对老龄人及行动不便患者在如厕时存在难以自行站立的问题,设计了一款辅助站立坐便器。首先在对人体自然站立阶段分析的基础上采集了关节运动轨迹数据,提出了辅助站立装置要尽可能地还原自然站立状态需要满足三个原则;其次对菱形传动... 针对老龄人及行动不便患者在如厕时存在难以自行站立的问题,设计了一款辅助站立坐便器。首先在对人体自然站立阶段分析的基础上采集了关节运动轨迹数据,提出了辅助站立装置要尽可能地还原自然站立状态需要满足三个原则;其次对菱形传动机构进行分析计算,并对关节理论轨运动迹进行了评估;再次设计了辅助站立机构的功能尺寸,并对其运动稳定性进行了评价;最后通过搭建的原型装置完成了辅助站立实验,结果表明髋关节与肩关节位移幅值分别为22cm和46cm,与自然站立采集结果基本吻合。辅助装置可以还原自然站立状态。 展开更多
关键词 辅助站立 关节运动轨迹 设计原则 菱形机构 功能尺寸
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基于生态原则的青藏高原行政区划调整思考
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作者 潘峰华 刘紫星 +1 位作者 葛岳静 宋长青 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期106-111,共6页
在生态文明建设的新时代,传统行政区划原则和我国的行政区划调整实践对生态因素考虑不够,甚至与生态治理产生了冲突.本文提出行政区划要注重生态原则,要以有利于生态保护和开发作为行政区划调整和优化的重要出发点.在生态意义重大的地区... 在生态文明建设的新时代,传统行政区划原则和我国的行政区划调整实践对生态因素考虑不够,甚至与生态治理产生了冲突.本文提出行政区划要注重生态原则,要以有利于生态保护和开发作为行政区划调整和优化的重要出发点.在生态意义重大的地区,行政区划调整应该成为提升生态治理、促进生态文明建设的重要手段.依据生态原则调整和优化行政区划,要充分发挥生态功能区划的指导作用.青藏高原是我国重要的生态安全屏障,但是行政区划的分割在一定程度上影响了生态治理,重要生态项目的规划建设也对现有的行政区划格局提出了挑战.未来应该考虑将行政区划调整作为促进青藏高原生态治理的手段,通过发挥行政区划的资源效应,提升青藏高原的空间治理能力,促进生态文明建设. 展开更多
关键词 行政区划 生态原则 空间治理 生态文明建设 青藏高原
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分布式电源对电力系统电压无功优化影响的研究
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作者 李斌 罗晓伊 《电气技术》 2024年第10期55-61,78,共8页
为研究分布式电源接入电力系统后的电压和无功优化问题,提出基于多代理系统(MAS)的一种电压无功优化协调控制新方法。以系统网损最小为目标,同时考虑电压稳定性,通过MAS构建以辅助问题原理进行分区分布式计算的电压无功优化协调控制模型... 为研究分布式电源接入电力系统后的电压和无功优化问题,提出基于多代理系统(MAS)的一种电压无功优化协调控制新方法。以系统网损最小为目标,同时考虑电压稳定性,通过MAS构建以辅助问题原理进行分区分布式计算的电压无功优化协调控制模型,并通过分区并行求解获得全局最优解,得到最优网损和节点电压稳定数据;研究单个和多个分布式电源接入后,系统电压无功变化情况,通过分析得出分布式电源的最佳接入位置,即分布式电源从此点接入对系统电压无功的影响效果最好。最后,利用EPRI-36节点系统进行仿真计算,结果证明了所提方法的合理性与正确性。 展开更多
关键词 分布式电源 无功优化 电压稳定 多代理 辅助问题原理 协调控制
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基于数据挖掘探析《中医方剂大辞典》中妇人癥瘕组方规律
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作者 任依凡 赵永庆 +2 位作者 李享书 程林南 李冰冰 《基层中医药》 2024年第2期105-111,共7页
目的基于中医传承辅助系统挖掘探析《中医方剂大辞典》中妇人癥瘕用药组方规律。方法筛选《中医方剂大辞典》中主治妇人癥瘕的方剂,运用中医传承辅助平台(V2.5),录入方剂信息,构建数据库,使用软件的Apriori关联规则、熵层次聚类等数据... 目的基于中医传承辅助系统挖掘探析《中医方剂大辞典》中妇人癥瘕用药组方规律。方法筛选《中医方剂大辞典》中主治妇人癥瘕的方剂,运用中医传承辅助平台(V2.5),录入方剂信息,构建数据库,使用软件的Apriori关联规则、熵层次聚类等数据挖掘方法,分析妇人癥瘕用药组方规律。结果共纳入274首方剂,313味中药,主归肝、脾两经,性味以辛、温为主,高频药物有当归、肉桂、大黄、桃仁等,高频药物组合有当归-赤芍、当归-川芎、当归-延胡索等,并衍生候选新方8组。结论历代医家论治妇人癥瘕时多重视肝、脾两脏,用药以活血化瘀药为主,在此基础上还兼顾扶正、温通之品的应用,以及注重虫类药运用,为临床治疗提供一定借鉴指导作用。 展开更多
关键词 妇人癥瘕 中医方剂大辞典 中医传承辅助系统 组方规律
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Auxiliary principle and three-step iterative algorithms for generalized set-valued strongly nonlinear mixed variational-like inequalities 被引量:1
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作者 徐海丽 郭兴明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第6期721-729,共9页
An auxiliary principle technique to study a class of generalized set-valued strongly nonlinear mixed variational-like inequalities is extended. The existence and uniqueness of the solution of the auxiliary problem for... An auxiliary principle technique to study a class of generalized set-valued strongly nonlinear mixed variational-like inequalities is extended. The existence and uniqueness of the solution of the auxiliary problem for the generalized set-valued strongly nonlinear mixed variational-like inequalities are proved, a novel and innovative three-step iterative algorithm to compute approximate solution is constructed, and the existence of the solution of the generalized set-valued strongly nonlinear mixed variational-like inequality is shown using the auxiliary principle iterative sequences generated by the algorithm technique. The convergence of three-step is also proved. 展开更多
关键词 mixed variational-like inequality three-step iterative algorithm set-valued mapping auxiliary principle technique
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On Solving a System of Generalized Mixed Equilibrium-like Problems in Hilbert Spaces
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作者 LIU Bang-tao LUO Min 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期180-189,共10页
A system of generalized mixed equilibrium-like problems is introduced and the existence of its solutions is shown by using the auxiliary principle technique in Hilbert spaces.
关键词 equilibrium-like problem auxiliary principle iterative algorithm Hilbert space
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Some New Systems of Exponentially General Equations
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作者 Muhammad Aslam Noor Khalida Inayat Noor 《Advances in Linear Algebra & Matrix Theory》 2022年第3期67-86,共20页
Some new systems of exponentially general equations are introduced and investigated, which can be used to study the odd-order, non-positive and nonsymmetric exponentially boundary value problems. Some important and in... Some new systems of exponentially general equations are introduced and investigated, which can be used to study the odd-order, non-positive and nonsymmetric exponentially boundary value problems. Some important and interesting results such as Riesz-Frechet representation theorem, Lax-Milgram lemma and system of absolute values equations can be obtained as special cases. It is shown that the system of exponentially general equations is equivalent to nonlinear optimization problem. The auxiliary principle technique is used to prove the existence of a solution to the system of exponentially general equations. This technique is also used to suggest some new iterative methods for solving the system of the exponentially general equations. The convergence analysis of the proposed methods is analyzed. Ideas and techniques of this paper may stimulate further research. 展开更多
关键词 General Equations Lax-Milgram Lemma Auxiliary Principle Iterative Method Convergence
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明式椅凳类家具赶枨部件构造特征与设计匠意研究 被引量:2
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作者 牛晓霆 龚娇 《家具与室内装饰》 北大核心 2023年第4期36-41,共6页
赶枨结构是指明式家具框架结构中地平面水平方向上与腿足垂直相交的系列横枨的组合结构。其主要分布在家具的前后、两侧、下盘处,用于加固和稳定腿足,显著提升了明式家具框架结构的力学性能。从赶枨结构的实用功能出发,以其在家具中的... 赶枨结构是指明式家具框架结构中地平面水平方向上与腿足垂直相交的系列横枨的组合结构。其主要分布在家具的前后、两侧、下盘处,用于加固和稳定腿足,显著提升了明式家具框架结构的力学性能。从赶枨结构的实用功能出发,以其在家具中的分布位置和不同的组织形式为划分依据,对明式椅凳类家具中的赶枨结构与辅助性构件进行分类,并按照所划分的不同结构类型梳理和归纳不同赶枨结构的构造特征和构造原理。研究结果表明,明式家具赶枨结构是科学与艺术的结合体,赶枨结构在腿足间位置的不同、枨子间位置关系的变换包括搭配构件的使用,均与家具整体结构的稳固有关。这对于国家非物质文化的传承与弘扬及明式家具理论的研究具有意义和价值。 展开更多
关键词 赶枨结构 辅助性构件 构造特征 构造原理
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OFDM技术的发展研究
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作者 孙华 《价值工程》 2014年第32期57-58,共2页
随着通信技术的逐步发展成熟,OFDM技术作为一种重要的多载波调制技术应运而生。本文详细介绍了OFDM技术的基本原理和特性,并对其主要优点做了系统分析,描述了其应用前景。
关键词 正交频分复用 基本原理 系统性能 研究
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