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EVALUATION OF SOFTWARE OF FOUR-PARAMETER SINE WAVE CURVE -FIT 被引量:2
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作者 梁志国 路克杰 孙璟宇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期100-106,共7页
Sinusoid curve fit is a very useful method in precise measurement, based on the modeling measurement. There are many valuable uses. But, what′s the specifications of the sinusoid curve fit software, and how to eval... Sinusoid curve fit is a very useful method in precise measurement, based on the modeling measurement. There are many valuable uses. But, what′s the specifications of the sinusoid curve fit software, and how to evaluate the uncertainty of it are still unknown yet, because they involve manifold factors and are complicated. Every one using the sinusoid curve fit software wants to know it. In this paper, the basic process and the uses of sinusoid curve fit are described, and some specifications and evaluation methods are introduced. One evaluation example of sinusoid curve fit software is discussed, the results and the specification are good. 展开更多
关键词 SOFTWARE EVALUATIONS measurements sine wave curve fit
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Research of sine waveguide slow-wave structure for a 220-GHz backward wave oscillator 被引量:1
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作者 许雄 魏彦玉 +4 位作者 沈飞 黄民智 唐涛 段兆云 宫玉彬 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期543-547,共5页
A watt-class backward wave oscillator is proposed, using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz. Firstly, the dispersion curve of the sine waveguide i... A watt-class backward wave oscillator is proposed, using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz. Firstly, the dispersion curve of the sine waveguide is calculated, then, the oscillation frequency and operating voltage of the device are predicted and the circuit transmission loss is calculated. Finally, the particle-in-cell simulation method is used to forecast its radiation performance. The results show that this novel backward wave oscillator can produce over 1-W continuous wave power output in a frequency range from 210 GHz to 230 GHz. Therefore, it will be considered as a very promising high-power millimeter-wave to terahertz-wave radiation source. 展开更多
关键词 backward wave oscillator sine waveguide slow-wave structure TERAHERTZ
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Controlling a sine wave gating single-photon detector by exploiting its filtering loophole
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作者 Lin-Xi Feng Mu-Sheng Jiang +3 位作者 Wan-Su Bao Hong-Wei Li Chun Zhou Yang Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期124-129,共6页
GHz single-photon detector (SPD) is a crucial part in the practical high speed quantum key distribution (QKD) system. However, any imperfections in a practical QKD system may be exploited by an eavesdropper (Eve... GHz single-photon detector (SPD) is a crucial part in the practical high speed quantum key distribution (QKD) system. However, any imperfections in a practical QKD system may be exploited by an eavesdropper (Eve) to collect information about the key without being discovered. The sine wave gating SPD (SG-SPD) based on InGaAs/InP avalanche photodiode, one kind of practical high speed SPD, may also contain loopholes. In this paper, we study the principle and characteristic of the SG-SPD and find out the filtering loophole of the SG-SPD for the first time. What is more, the proof-of-principle experiment shows that Eve could blind and control Bob's SG-SPD by exploiting this loophole. We believe that giving enough attention to this loophole can improve the practical security of the existing QKD system. GHz single-photon detector (SPD) is a crucial part in the practical high speed quantum key distribution (QKD) system. However, any imperfections in a practical QKD system may be exploited by an eavesdropper (Eve) to collect information about the key without being discovered. The sine wave gating SPD (SG-SPD) based on InGaAs/InP avalanche photodiode, one kind of practical high speed SPD, may also contain loopholes. In this paper, we study the principle and characteristic of the SG-SPD and find out the filtering loophole of the SG-SPD for the first time. What is more, the proof-of-principle experiment shows that Eve could blind and control Bob's SG-SPD by exploiting this loophole. We believe that giving enough attention to this loophole can improve the practical security of the existing QKD system. 展开更多
关键词 quantum key distribution sine wave gating single-photon detector quantum hacking practicalsecurity
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NEW THREE PHASE VFVA SINE WAVE GENERATOR AND PWM HARMONICS ANALYSIS
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作者 林棋 《Journal of Electronics(China)》 1994年第1期79-87,共9页
The new three phase VFVA sine wave generator is presented in this paper. A new sampling holding three phase VFVA sine wave generator’s principle, circuit and experimentation waveform are introduced. The principle of ... The new three phase VFVA sine wave generator is presented in this paper. A new sampling holding three phase VFVA sine wave generator’s principle, circuit and experimentation waveform are introduced. The principle of this sampling holding circuit is simple and the realization of har’dware circuit is easy. Here we describe the three phase reference sine wave which is produced by this generator’s circuit and is required by PWM inverter is described in this paper, and also introduced the speed control and harmonir analysis of PWM inverter variable frequency. 展开更多
关键词 sine wave GENERATOR HARMONICS analysis THREE phase VFVA
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Longitudinal injection scheme for an ultra-low-emittance storage ring light source with a sine wave kicker
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作者 Kun Wang Chang-Liang Li +3 位作者 Zheng-He Bai Man-Zhou Zhang Qing-Lei Zhang Bo-Cheng Jiang 《Radiation Detection Technology and Methods》 CSCD 2019年第4期29-37,共9页
Methods The method of longitudinal injection to an ultra-low emittance storage ring by a sine wave kicker is investigated in this paper.Beam dynamics of the injected and stored beams are both studied.With a third-harm... Methods The method of longitudinal injection to an ultra-low emittance storage ring by a sine wave kicker is investigated in this paper.Beam dynamics of the injected and stored beams are both studied.With a third-harmonic kicker,the emittance and the orbit of the stored beam can be well preserved and the injection efficiency can reach 100%. 展开更多
关键词 Longitudinal injection Storage ring sine wave kicker
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Spectral Target-Detecting System Using Sine-Wave Modulation 被引量:1
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作者 DENG Wei ZHAO Chun-jiang +2 位作者 ZHANG Lu-da CHENG Li-ping Andrew Landers 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2011年第10期2771-2777,共7页
Target detection is one of the key technology of precision chemical application.Previously the digital coding modulation technique was commonly used to emit and receive the optical signal in the target detection syste... Target detection is one of the key technology of precision chemical application.Previously the digital coding modulation technique was commonly used to emit and receive the optical signal in the target detection systems previously in China.It was difficult to adjust the output power,and the anti-interference ability was weak in these systems.In order to resolve these problems,the target detection method based on analog sine-wave modulation was studied.The spectral detecting system was set up in the aspects of working principle,electric circuit,and optical path.Lab testing was performed.The results showed that the reflected signal from the target varied inversely with detection distances.It indicated that it was feasible to establish the target detection system using analog sine-wave modulation technology.Furthermore,quantitative measurement of the reflected optical signal for near-infrared and visible light could be achieved by using this system.The research laid the foundation for the future development of the corresponding instrument. 展开更多
关键词 sine-wave modulation ANALOG Target detection Optical spectrum
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Partial sine wave tracking dual mode control topology for a single-phase transformerless photovoltaic system
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作者 Koki OGURA Mohan Lal KOLHE Mutsuo NAKAOKA 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2018年第6期1338-1343,共6页
A unique high efficiency photovoltaic(PV)system is presented. It uses partial sine wave tracking for a pulse-width modulation(PWM) boost converter as well as a full-bridge inverter. The boost converter and full-bridge... A unique high efficiency photovoltaic(PV)system is presented. It uses partial sine wave tracking for a pulse-width modulation(PWM) boost converter as well as a full-bridge inverter. The boost converter and full-bridge inverter are connected via a compact intermediate film capacitor(i.e. non-smoothing DC link stage). PWM switching is activated by a dual mode control technique. In the proposed topology, simultaneous switching of both power conversion stages is avoided and therefore this increases the power conversion efficiency. The distinctive operating principles of these two power processing stages are discussed and analyzed with the experimental results for single-phase loading of the PV system. 展开更多
关键词 PARTIAL sine wave instantaneous TRACKING PULSEWIDTH modulation(PWM) boost converter BYPASS diode Dual mode CONTROL High efficiency power conversion
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(2+1)维双sine-Gordon方程新的无穷序列精确解
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作者 吴国将 吁艳林 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第6期37-46,共10页
(2+1)维双sine-Gordon方程常用于描述非线性光学、超流体及铁磁材料等领域的非线性波现象.提出一种新的无穷序列孤立波解和周期波解的构造方法.将Riccati方程作为辅助方程,通过不同迭代关系求解Riccati方程,得到该方程许多新的双曲函数... (2+1)维双sine-Gordon方程常用于描述非线性光学、超流体及铁磁材料等领域的非线性波现象.提出一种新的无穷序列孤立波解和周期波解的构造方法.将Riccati方程作为辅助方程,通过不同迭代关系求解Riccati方程,得到该方程许多新的双曲函数解和三角函数解.将所得到的解代入(2+1)维双sine-Gordon方程,获得了(2+1)维双sine-Gordon方程的大量新无穷序列精确孤立波解和周期波解,这些解的大部分在其他文献中未见报道. 展开更多
关键词 (2+1)维双sine-Gordon方程 孤立波解 周期波解 无穷序列解
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Travelling Wave Solutions to the m-KdV-Sine-Gordon Equation and the m-KdV-Sinh-Gordon Equation
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作者 LI Er-qiang CHEN Jin-lan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期82-86,共5页
By using the function transformation and proper Sub-ODE, exact travelling wave solutions of the m-KdV-Sine-Gordon and the m-KdV-Sinh-Gordon equation are obtained, from which exact travelling wave solutions of the m-Kd... By using the function transformation and proper Sub-ODE, exact travelling wave solutions of the m-KdV-Sine-Gordon and the m-KdV-Sinh-Gordon equation are obtained, from which exact travelling wave solutions of the m-KdV equation, the Sine-Gordon equation and the Sinh-Gordon equation are derived. 展开更多
关键词 function transformation m-KdV-sine-Gordon equation m-KdV-Sinh-Gordon equation Sub-ODE travelling wave solutions
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渭北地区中更新世黄土的压电性试验研究
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作者 井彦林 刘杰 +3 位作者 刘清颖 段晓晓 谢娜 杨登科 《煤田地质与勘探》 北大核心 2025年第1期184-192,共9页
【背景】石英为最早被发现的压电材料,石英的压电性在工业、军事及人们的日常生活等方面均得到了广泛应用。黄土在世界上分布较广,其主要矿物成分为石英,石英质量分数为37.0%~69.9%,但目前国内外对黄土的压电性少有研究。【方法】为了... 【背景】石英为最早被发现的压电材料,石英的压电性在工业、军事及人们的日常生活等方面均得到了广泛应用。黄土在世界上分布较广,其主要矿物成分为石英,石英质量分数为37.0%~69.9%,但目前国内外对黄土的压电性少有研究。【方法】为了探讨黄土的压电性,以陕西渭北黄土Qeol2塬黄土为研究对象,对其压电系数进行测定,并对黄土在静力作用下及振动作用下的压电电压进行试验研究。【结果和结论】结果表明:黄土具有压电性。基于黄土的压电性,可制作压电式电池,也可进行压电式发电。黄土的压电性与其厚度无关,与干密度、含水率相关。干密度越小、含水率越高,压电性越强,压电系数越大,反之,压电系数越小;黄土在天然密度及天然含水率状态下,其压电系数为16.1pC/N。在静力作用下,压电电压信号为正弦波,波形较规则,电压频率10MHz,周期100ns。静力作用下压电电压可达到0.6V以上;多个试样串联连接,则电压值累加式增高。在振动作用下,黄土压电电压显著增高,且在不同的振动频率作用下电压不同,共振作用下压电电压最高,共振时单个黄土试样电压最大值超过2.1V。在振动及上部荷载双重作用下,以(黄土)压电式电池替代传统汽车电池的可行性研究无疑是一个备受关注的课题,同时,基于黄土的压电性,在黄土地区进行土壤湿度、地震活动监测以及卓越周期测试等方面的研究颇具理论和实际意义,研究成果可为上述研究提供重要参考和借鉴。 展开更多
关键词 黄土 压电性 影响因素 正弦波 压电式发电 汽车电池
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sine-Gordon型方程的新的孤立波解 被引量:4
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作者 套格图桑 斯仁道尔吉 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2004年第4期361-365,共5页
用新辅助方程和函数变换,构造了sine Gordon方程、双sine Gordon方程、sinh Gordon方程和Otherthirdorder方程的新的精确孤立波解.
关键词 精确孤立波解 齐次平衡法 精确解 辅助方程 和函数 超导物理 双曲正切函数 离子 解构 求解
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用修正的F-展开法求解(n+1)维Sine-Gordon方程 被引量:9
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作者 卢殿臣 洪宝剑 田立新 《兰州理工大学学报》 CAS 北大核心 2007年第1期139-142,共4页
用一个未知函数的变换将(n+1)维Sine-Gordon方程转化为新未知函数及其偏导数为变元的多项式型的非线性偏微分方程.在拟设法、齐次平衡法和Jacobi椭圆函数法的基础上,借助Mathematica软件和修正的F-展开法,求出了(n+1)维SG方程的Weierstr... 用一个未知函数的变换将(n+1)维Sine-Gordon方程转化为新未知函数及其偏导数为变元的多项式型的非线性偏微分方程.在拟设法、齐次平衡法和Jacobi椭圆函数法的基础上,借助Mathematica软件和修正的F-展开法,求出了(n+1)维SG方程的Weierstrass椭圆函数解、Jacobi椭圆函数表示的双周期波解,研究了极限情况下解的退化形式,利用数学软件绘出了部分解对应的图形.研究表明,许多解在欧氏变换下是等价的. 展开更多
关键词 修正的F-展开法 (n+1)维sine-Gordon方程 周期波解 JACOBI椭圆函数 孤立波解
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基础激励下的振动台变压器虚拟试验研究
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作者 钱海玥 胡冠杰 +1 位作者 张在超 李翠翠 《变压器》 2025年第1期51-60,共10页
针对变压器因振动台基础激励引起的强度问题,本文作者应用虚拟试验技术和振动学理论研究两种构型的变压器的动力学特性。基于基础激励条件下的虚拟试验模型,应用模态分析理论,通过分析变压器的振型和固有频率,得到其薄弱环节。采用模态... 针对变压器因振动台基础激励引起的强度问题,本文作者应用虚拟试验技术和振动学理论研究两种构型的变压器的动力学特性。基于基础激励条件下的虚拟试验模型,应用模态分析理论,通过分析变压器的振型和固有频率,得到其薄弱环节。采用模态叠加法和冲击动力学理论,并结合瑞利阻尼模型,得到两种构型的变压器在正弦信号激励和半正弦波冲击时的应力和变形云图。研究结果显示:两种构型的变压器的侧向均为结构的最薄弱方向。变压器的长边底座单边长度减短25mm,对其基频和正弦信号激励下共振点处的变形有重大影响,但对其高频、振型、正弦信号激励下共振点处的应力以及半正弦波冲击下的动强度影响较小。在半正弦波冲击下,高量值的冲击过载对两种构型变压器的动力学特性有重大影响。该研究结果可为变压器优化设计提供理论基础。 展开更多
关键词 变压器 虚拟试验 基础激励 正弦激励 半正弦冲击波
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Sine-Gordon方程新的行波解
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作者 杨琼芬 杜先云 《聊城大学学报(自然科学版)》 2008年第2期33-35,共3页
利用F-展开法,得到了sine-Gordon方程一些新的精确解,其中包括新的孤立子波解.
关键词 F-展开法 sine-GORDON方程 行波解
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利用从sine-Gordon方程得到的变换求解非线性波动方程(英文)
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作者 扎其劳 斯仁道尔吉 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2005年第3期266-271,共6页
对一种求解非线性波动方程的新方法进行了扩展,并对其中的关键操作步骤做了改进.利用改进后的方法可以构造出一些新的非线性波动方程的精确解.
关键词 sine-GORDON方程 JACOBI椭圆函数 非线性波动方程 周期波解 孤立波解
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Sine-Gordon方程的新精确孤波与周期孤波解 被引量:1
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作者 李自田 《成都大学学报(自然科学版)》 2010年第2期112-114,共3页
应用变量分离常微分方程方法与辅助常微笑分方程方法得到了Sine-Gordon方程的新精确孤波与周期孤波解.
关键词 sine-GORDON方程 变量分离 辅助常微分方程 孤波解 周期解
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近似Sine-Gordon方程的孤子解
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作者 刘均华 《常德师范学院学报(自然科学版)》 2002年第2期8-9,42,共3页
采用行波法和近年来发展的齐次平衡法求解一类运用广泛的Sine -Gordon方程 ,获得形如tanh(x -vt)的扭结孤子解 .针对齐次平衡法出现解遗漏的情况 。
关键词 近似sine-Gordon方程 齐次平衡法 行波法 孤子解
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非线性Boussinesq方程的新孤立波解
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作者 贺锋 戴甲展 《零陵学院学报》 2003年第5期10-12,共3页
利用非线性Sine-Gordon方程的一种新变换可精确求解非线性Boussinesq方程,得到两个新孤立波解。
关键词 sine—Gordon方程 JACOBI椭圆函数 孤立波解 BOUSsineSQ方程
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双sine-Gordon方程的新的精确行波解 被引量:1
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作者 娜仁 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2007年第1期22-24,60,共4页
基于符号计算和Riccati方程解的新展式,利用扩展的双曲正切函数法给出双sine-Gordon方程的新的精确行波解.
关键词 Riceati方程 sine-Gordon方程 行波解
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变系数sine-Gordon方程的几种新解 被引量:1
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作者 范俊杰 套格图桑 《内蒙古大学学报(自然科学版)》 CAS 北大核心 2016年第4期347-351,共5页
通过函数变换,将变系数sine-Gordon方程的求解问题转化为二维线性波动方程的求解问题.然后利用波动方程的解,构造了变系数sine-Gordon方程的新解,并借助符号计算系统Mathematica,分析了解的性质.
关键词 函数变换 二维线性波动方程 变系数sine-Gordon方程
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