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隆格-楞次矢量在高中物理竞赛中的应用
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作者 郑荣炜 王成睿 +1 位作者 黄张铃 陈诺涵 《物理通报》 2025年第2期72-75,共4页
介绍在平方反比有心力场下的重要守恒量——隆格楞次矢量(简称LRL矢量).运用LRL矢量相关物理规律分别对高中物理竞赛中常见的行星轨道方程、行星进动角以及α粒子散射实验散射角等计算问题进行了解答.
关键词 LRL矢量守恒 有心力 高中物理竞赛
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LRL校准法及其在微波测量中的应用 被引量:8
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作者 廖进昆 刘仁厚 《电子科技大学学报》 EI CAS CSCD 北大核心 2000年第2期149-152,共4页
讨论了微波器件的测量问题,阐明了LRL(Line-Reflect-Line)校准法的物理模型。应用微波网络理论建立了基本方程,运用矩阵方法推导出待测件散射参量的闭定式表达式。由于利用代数消去法,去除了嵌入参量相位不确... 讨论了微波器件的测量问题,阐明了LRL(Line-Reflect-Line)校准法的物理模型。应用微波网络理论建立了基本方程,运用矩阵方法推导出待测件散射参量的闭定式表达式。由于利用代数消去法,去除了嵌入参量相位不确定性引入的误差,LRL法可用于微波晶体管测试夹具的去嵌入。 展开更多
关键词 微波测量 去嵌入 LRL校准法 微波器件
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矢量网络分析仪的校准方法 被引量:4
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作者 樊中山 《国外电子测量技术》 2003年第5期35-36,40,共3页
从误差网络模型出发,解释了两端口矢量网络分析仪的校准原理。根据实际测试精度要求和测试条件,介绍了几种不同的校准程序,对可能导致精度降低的因素加以分析。
关键词 误差网络 矢量网络分析仪 校准程序 LRL校准
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微带铁氧体器件测试夹具LRL校准与设计
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作者 韩晓川 闫欢 +1 位作者 胡艺缤 杨洋 《磁性材料及器件》 CAS 2017年第5期40-43,共4页
对于传统微波无源器件S参数的测量,通常是先在矢量网络分析仪上对同轴端进行SOLT的全二口校准,再通过测试夹具对微带器件进行测试,测试夹具引入了一定的测试误差。为实现微带双端口器件的准确测试,设计了用于LRL校准方法的测试夹具及校... 对于传统微波无源器件S参数的测量,通常是先在矢量网络分析仪上对同轴端进行SOLT的全二口校准,再通过测试夹具对微带器件进行测试,测试夹具引入了一定的测试误差。为实现微带双端口器件的准确测试,设计了用于LRL校准方法的测试夹具及校准件。介绍了校准原理及校准件设计,通过HFSS仿真软件对测试夹具进行仿真优化,设计制作了LRL精确校准的测试夹具及校准件。对X波段微带器件进行测试,验证LRL测试夹具测试的准确性。 展开更多
关键词 微带铁氧体器件 LRL校准 测试夹具
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Hodographs of the Gravitational Two-Body System and Discrepancies between Newtonian Laws of Equivalent Kepler Orbits and General Relativity
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作者 Caesar P. Viazminsky Piere K. Vizminiska 《Applied Mathematics》 2014年第1期55-69,共15页
We show first that an orbit, which is naturally characterized by its eccentricity and semi-latus rectum, can equally be characterized by other sets of parameters, and proceed to determine mass-independent characteriza... We show first that an orbit, which is naturally characterized by its eccentricity and semi-latus rectum, can equally be characterized by other sets of parameters, and proceed to determine mass-independent characterizations. The latter is employed to obtain the laws of equivalent orbits, which by definition have the same eccentricity and orbit’s parameter [1]. These laws relate the values of the same physical observables on two equivalent orbits to the corresponding total mass;they include the laws of velocity, angular velocity, radial velocity, areal velocity, acceleration, period, energy and angular momentum. Regardless of the share of the two bodies of a fixed total mass, the same relative orbit occurs for the same initial conditions. Moreover, the same orbit can be traced by different total masses but with different relative velocities. The concept of a gravitational field generated by a set of masses is shown to be meaningful only when the center of mass is not changed by the test mass. The associated concept of the “nothing”, which is an infinitesimal mass that allows for the property just mentioned to be fulfilled, is introduced and its orbits are determined. The perturbation of the nothing orbits due to its replacement by a finite mass is determined. It is proved that such a replacement can have a qualitative effect resulting in a “phase transition” of an orbit from unbound to bound, and that the nothing’s circular orbits cannot be occupied by any material body. The Galileo law of free fall, on which the equivalence principle hinges and which is exact only for “nothing-like” falling objects, is revised to determine the duration of free fall of a body of an arbitrary mass. The wholeness of Newton’s laws and the associated concept of force as an interaction are highlighted, and some contradictions between the Newtonian laws of equivalent Kepler’s orbits and the general relativistic predictions are discussed. It is demonstrated that Newton’s law of gravitation is not an approximation of Einstein field Equations even in the case of a static weak field. However, both theories have a common limit corresponding to the case in which the alien concept of a field can be incorporated in the Newtonian theory. We also show that the relative velocity’s hodograph [2-4], the alternative Laplace-Runge-Lenz (LRL) vector derived by Hamilton [4-6], as well as an infinite set of LRL vectors, result all from one vector. The hodograph is a proper circular arc for hyperbolic motion, a circle less a point for parabolic motion, and a full circle for bound motion. 展开更多
关键词 Hodographs LRL Vector LAWS of EQUIVALENT ORBITS Revised Galileo Law of Free Fall Equivalence Principle
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为中国农机现代化再作贡献东方红LR系列柴油机家族又添新军——LR108系列柴油机
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《农机市场》 2004年第10期49-49,共1页
秉承科技造福人类,全力服务社会的理念,一拖(洛阳)柴油机有限公司与英国里卡多公司携手,三年磨剑,推出LR108系列柴油机,为中国的农机现代化再做贡献。
关键词 LRl08系列柴油机 一拖柴油机有限公司 整机刚度 农机现代化 东方红LR系列产品 技术指标
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LR108系列柴油机横空出世
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《农机市场》 2004年第8期47-47,共1页
关键词 农机现代化 中国 东方红LR系列柴油机 一拖柴油机有限公司 LRl08系列柴油机 技术创新 产品性能 新产品开发 设计理念
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