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A Key to Solving the Angle Trisection Problem
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第9期625-634,共10页
This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach ... This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach that required first, designing a working model of a trisector mechanism, second, studying the motion of key elements of the mechanism and third, applying the fundamental principles of kinematics to arrive at the desired results. In presenting these results, since there was no requirement to provide a detailed analysis of the final construction, this information was not included. However, now that the publication is out, it is considered appropriate as well as instructive to explain more fully the mechanism analysis of the trisector in graphical detail, as covered in Section 3 of this paper, that formed the basis of the long sought solution to the age-old Angle Trisection Problem. 展开更多
关键词 Archimedes’ Construction College Geometry College Mathematics Angle Trisection trisector Famous Problems in Mathematics History of Mathematics Mechanism Analysis Kinematics Geometer’s Sketch Pad
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A Simplified Graphical Procedure for Constructing a 10˚or 20˚Angle
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第7期442-448,共7页
This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when... This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be not trisectable, produced a construction having the identical angular relationship with Archimedes’ Construction, in which the required trisection angles were found to be 10.00000˚ and 20.00000˚ respectively (i.e. exactly one-third of the given angle or ∠E’MA = 1/3∠E’CG). Based on this identical angular relationship as well as the numerical results obtained, one can only conclude that the geometric requirements for arriving at an exact trisection of the 30˚ or 60˚ angle, and therefore the construction of a 10˚ or 20˚ angle, have been met, notwithstanding the theoretical proofs of Wantzel, Dudley, and others. Thus, the solution to the age-old trisection problem, with respect to these two angles, has been accomplished. 展开更多
关键词 Archimedes’ Construction College Geometry Angle Trisection Trisection of an Angle Famous Problems in Mathematics. Geometer’s Sketch Pad Mechanisms Mechanism Analysis Kinematics trisector
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三分仓回转式空气预热器漏风综合治理 被引量:7
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作者 潘效军 马金凤 吴景兴 《中国电力》 CSCD 北大核心 2002年第7期22-25,共4页
针对三分仓回转式空气预热器在结构、安装、运行等方面所存在的漏风问题及主要缺陷进行简要分析,全面阐述目前国内外在漏风治理方面所采用的技术措施,对三分仓回转式空气预热器漏风治理具有一定的参考价值。
关键词 三分仓回转式空气预热器 漏风 综合治理 锅炉
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三分仓空气预热器一次风的泄漏问题初探 被引量:19
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作者 王建明 曹佳鸣 《动力工程》 CSCD 1999年第5期403-405,共3页
三分仓空气预热器一次风泄漏量偏大,引起国内部分用户的反响。该文作者从空气预热器漏风率和一次风泄漏率的定义出发,分析产生一次泄漏量差异的原因,以及如何正确认识这一问题。
关键词 锅炉 空气预热器 三分仓 一次风 泄漏
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A Procedure for Trisecting an Acute Angle 被引量:1
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2022年第2期63-69,共7页
This paper presents a graphical procedure, using an unmarked straightedge and compass only, for trisecting an arbitrary acute angle. The procedure, when applied to the 30&#730;angle that has been “proven” to be ... This paper presents a graphical procedure, using an unmarked straightedge and compass only, for trisecting an arbitrary acute angle. The procedure, when applied to the 30&#730;angle that has been “proven” to be not trisectable, produced a construction having the identical angular relationship with Archimedes’ Construction, in which the required trisection angle was found to be exactly one-third of the given angle (or &#8736;E'MA = 1/3&#8736;E'CG = 10&#730;), as shown in Figure 1(D) and Figure 1(E) and Section 4 PROOF in this paper. Hence, based on this identical angular relationship between the construction presented and Archimedes’ Construction, one can only conclude that geometric requirements for arriving at an exact trisection have been met, notwithstanding the theoretical proofs of Wantzel, Dudley, and others. 展开更多
关键词 Archimedes’ Construction College Geometry Angle Trisection trisectors Famous Problems in Mathematics History of Mathematics
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在扇区天线环境下的子空间干扰对齐技术 被引量:2
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作者 陈俊卿 郑宝玉 元超 《信号处理》 CSCD 北大核心 2013年第5期577-583,581-583,共7页
最近一些研究表明,干扰对齐算法可以在高信噪比的情况下使干扰信道容量接近香农容量。干扰对齐的主要思想是将来自其他基站的干扰信号对齐到相同的信号子空间,而将有用信号放在完全没有干扰的信号子空间进行传输。本文考虑每个基站采用... 最近一些研究表明,干扰对齐算法可以在高信噪比的情况下使干扰信道容量接近香农容量。干扰对齐的主要思想是将来自其他基站的干扰信号对齐到相同的信号子空间,而将有用信号放在完全没有干扰的信号子空间进行传输。本文考虑每个基站采用基于子空间干扰对齐的方法,在扇区天线环境下,来实现小区间的干扰对齐。在很多文献中,提到了小区间的协作方案,这样往往会引起协作簇之间的干扰,本文采用扇区天线,通过三小区进行协作,避免协作簇之间的干扰。仿真结果表明本文所提算法可以有效降低干扰,进一步提高中断容量和频谱效率。 展开更多
关键词 基站协作传输 扇区天线 干扰对齐 预编码
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大尺度信干比共享下的基站协作干扰协调 被引量:2
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作者 陈俊卿 郑宝玉 魏浩 《信号处理》 CSCD 北大核心 2012年第11期1551-1557,共7页
在基于正交频分多址接入(OFDMA)技术的蜂窝移动小区中,小区间的干扰是影响系统性能的主要因素。多点协调(CoMP)技术被视为能够协调小区间干扰的主要手段。在下行多点协作传输系统中,小区基站采用三向天线来对小区划分扇区,从而消除了相... 在基于正交频分多址接入(OFDMA)技术的蜂窝移动小区中,小区间的干扰是影响系统性能的主要因素。多点协调(CoMP)技术被视为能够协调小区间干扰的主要手段。在下行多点协作传输系统中,小区基站采用三向天线来对小区划分扇区,从而消除了相邻小区边缘处的干扰。各扇区分别计算扇区内用户的大尺度信干比(SIR),小区之间通过共享大尺度信干比信息,对各自服务的用户按照一定的规则进行匹配,对小区中心用户的SIR和边缘用户的SIR进行了折中,从而有效解决小区边缘用户由于小区间干扰带来的低信干噪比(SINR)问题。仿真结果表明,本文提出的用户匹配算法以较小的反馈开销,较大地提高了小区边缘用户的信干噪比和系统吞吐量。 展开更多
关键词 基站协作传输 三向天线 大尺度信干比 协作用户选择
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论中国三元经济结构的产生 被引量:1
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作者 徐平川 朱荣 《昆明理工大学学报(理工版)》 2002年第2期84-88,共5页
中国的乡镇企业,由于制度选择的结果而取得了举足轻重的经济地位,这样就使中国的经济呈现出有别于刘易斯模式的“三元经济结构”文章对这种特殊经济结构的生成机制进行了分析和研究.
关键词 中国 乡镇企业 二元经济模型 三元经济结构 企业发展 产生机制
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