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Femtosecond laser modulated into Bessel beam by spatial light modulator for Fresnel zone plate processing
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作者 DUAN Lian ZHOU Fang +3 位作者 KONG De-jian ZHANG Fan SUN Xiao-yan DUAN Ji-an 《Journal of Central South University》 2025年第2期469-482,共14页
Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,... Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells. 展开更多
关键词 femtosend laser Fresnel zone plate spatial light modulator Bessel beam GAAS
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Protection against respiratory depression by novel allosteric AMPA receptor modulator
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作者 DAI Wei GAO Xiang +2 位作者 LI Yu-lei YONG Zheng SU Rui-bin 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第9期735-736,共2页
OBJECTIVE Respiratory depression hinders the use of anaesthetics and sedative hypnotics.For emergency use,specific antagonists are currently administered to counteract respiratory depression.However,antagonists are of... OBJECTIVE Respiratory depression hinders the use of anaesthetics and sedative hypnotics.For emergency use,specific antagonists are currently administered to counteract respiratory depression.However,antagonists are often short-lasting and can have multiple unexpected side effects.A novel AMPA receptor modulator LCX001,synthesized by our Institute of Medicinal Chemistry,is expected to relieve suppressed respiration.To explore the mechanism and impact of LCX001 on protection against respiratory depression.METHODS LCX001 was tested to alleviate respiratory depression triggered by opioid,propofol and pentobarbital in the plethysmography recording.The acetic acid writhing and hot-plate tests were conducted to evaluate potential analgesic effect of LCX001.Binding assay and whole-cell recording were used to analyze the property of LCX001 on positive modulation.The function of AMPA receptors were determined by location of receptors inthe membrane and state of channel opening,and both processes were impressed by AMPA receptor regulatory proteins.According to the theory,the effect of LCX001 on the expression of stargazin was measured firstly by Western blotting.The variation of receptor surface location were observed by live cell imaging.The regulation on neuronal Ca2+and cell function was investigated intensively by Ca2+imaging to clarify mechanism of LCX001.RESULTS LCX001 effectively rescued and prevented opioid(fentanyl and TH-030418),propofol,and pentobarbitalinduced respiratory depression by strengthening respiratory frequency and minute ventilation by 30%-50% in rats.The acetic acid writhing test and hot-plate test revealed potent anti-nociceptive efficacy of LCX001 on increasing the inhibition rate and %MPE to 80% and 65% respectively,in contrast to some ampakines that did not affect analgesia.Furthermore,LCX001 potentiated[3 H]AMPA and L-glutamate binding affinity to AMPA receptors,and facilitated glutamateevoked inward currents in HEK293 cells stably expressing GluA2(R).At 10 mmol·L^(-1) glutamate evoked amplitudes,LCX001 at 100 μmol·L^(-1) increased the potency of glutamate induced currents by(1120 ± 60) pA,compared with that of(752 ± 35) pA in the control group.LCX001 also prominently promoted steady state/peak amplitude ratio.LCX001 significantly slowed down the desensitization rates of the AMPA ion channel,and inhibited current decay.Importantly,application of LCX001 generated a significant increase in GluA2(R) surface expression in a mechanism of stargazin up-regulation,and restrained opioidinduced abnormal intracel ular Ca2+load,which might participate in breathing modulation.CONCLUSION The typical positive modulatory impact and potential new mechanism of LCX001 might promote ampakines to be a therapeutic option for protection against respiratory depression. 展开更多
关键词 RESPIRATORY DEPRESSION GLUTAMATE AMPA receptor modulator
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双级矩阵变换器Delta-Sigma变频调制策略
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作者 周湛清 谢琦坤 耿强 《天津工业大学学报》 北大核心 2025年第1期69-74,共6页
针对定开关频率调制下输出侧含有高频谐波边带的问题,提出了双级矩阵变换器变频调制策略,以提升双级矩阵变换器的电磁兼容性能以及运行性能。将Delta-Sigma矢量调制技术应用于双级矩阵变换器的逆变级中,基于仿真与实验结果分析了该调制... 针对定开关频率调制下输出侧含有高频谐波边带的问题,提出了双级矩阵变换器变频调制策略,以提升双级矩阵变换器的电磁兼容性能以及运行性能。将Delta-Sigma矢量调制技术应用于双级矩阵变换器的逆变级中,基于仿真与实验结果分析了该调制策略下的双级矩阵变换器运行性能。仿真与实验结果表明:本文所提调制策略有效实现了双级矩阵变换器输出电流的频谱整形,不再含有高频谐波尖峰,有效降低了输出侧相电流高频谐波边带的幅值;本文调制策略下双级矩阵变换器输出相电流THD最高为4.26%,最低为1.62%,相较于空间矢量调制策略输出相电流THD平均降低了0.256%,这表明本文策略具有良好的运行性能;动态实验结果表明该策略具有良好的动态特性。 展开更多
关键词 双级矩阵变换器 delta-sigma调制 变频调制 频谱整形 运行性能
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Waveguide electro-optic modulators based on self-assembled material systems 被引量:1
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作者 LIU Zhi-fu MA Jing +6 位作者 SUN De-gui XU Guo-yang HO Seng-Tiong ZHU Pei wang KANG Hu Antonio Facchetti Tobin J. Marks 《光学精密工程》 EI CAS CSCD 北大核心 2005年第5期554-560,共7页
Fabrication and characterization of electro-optic modulators based on the novel organic electro-optic materials composed of self-assembled superlattices (SAS) were presented, both wet-dipping self-assembly and vapor p... Fabrication and characterization of electro-optic modulators based on the novel organic electro-optic materials composed of self-assembled superlattices (SAS) were presented, both wet-dipping self-assembly and vapor phase deposition approaches were discussed. Prototype waveguide electro-optic modulators were fabricated using SAS films integrated with low-loss polymeric materials functioning as partial guiding and cladding layers.Promising electro-optic thin film materials including DTPT and PEPCOOH grown from the vapor phase were used for fabrication and test of electro-optic prototype modulators. Finally,the EO coefficient of tens of pm/V was obtained,which can sufficiently support high-speed and small size EO modulators. 展开更多
关键词 电子波导 光电子调节器 SAS 薄膜
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Magnetic-fluid microelectromechanical light modulator 被引量:6
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作者 SEO Jong-wook WANG Xi-jun 《光学精密工程》 EI CAS CSCD 北大核心 2005年第5期542-547,共6页
A new microfluidic microelectromechanical light modulator using a magnetic fluid is introduced. The optical reflection from the device is modulated by applying an electric current into an electrode, which is enclosed ... A new microfluidic microelectromechanical light modulator using a magnetic fluid is introduced. The optical reflection from the device is modulated by applying an electric current into an electrode, which is enclosed by ferromagnetic thin films as in an inductive head for a magnetic data storage device. The magnetic field produced by the current exerts a magnetic force on the magnetic fluid and drives the fluid to cover the cell surface. The surface tension of the fluid provides a restoring force when the field is reduced. The actuation of the fluid is completed in about 12 ms for both thin-to-thick and thick-to-thin fluid film switchings by magnetic forces and surface tension forces, respectively. It was observed that the switching speed was almost independent of the driving current, and no considerable thermal effect were observed when driven by a current up to 100 mA. 展开更多
关键词 微电子学 光调节器 磁性 流动性 FPD MEMS 弯曲效应 电极 有限元法 FEM
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Mechanism and impact of a novel allosteric AMPA receptor modulator on protection against respiratory depression 被引量:1
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作者 Wei DAI Xiang GAO +2 位作者 Yu-lei LI Zheng YONG Rui-bin SU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期276-277,共2页
OBJECTIVE Respiratory depression hinders the use of anaesthetics and sedative hyp.notics.To explore the mechanism of LCX001 on protection against respiratory depression,a novel AMPA receptor modulator LCX001,synthesiz... OBJECTIVE Respiratory depression hinders the use of anaesthetics and sedative hyp.notics.To explore the mechanism of LCX001 on protection against respiratory depression,a novel AMPA receptor modulator LCX001,synthesized by our Institute of Medicinal Chemistry,is expected to relieve suppressed respiration.METHODS LCX001 was tested to alleviate respiratory depression triggered by opioid(fentanyl and TH-030418),propofol and pentobarbital in the plethysmography recording.The acetic acid writhing and hot-plate tests were conducted to evaluate analgesic effect of LCX001.Binding assay and whole-cell recording were used to analyze the property of LCX001 on positive modulation.The function of AMPA receptors were determined by location of receptors in the membrane and state of channel opening,and both processes were impressed by AMPA receptor regulatory proteins.Ac.cording to the theory,the effect of LCX001 on the expression of stargazin was measured firstly by west.ern blotting.The variation of receptor surface location was observed by live cell imaging.The regula.tion on neuronal Ca^(2+) and cell function was investigated intensively by Ca^(2+) imaging to clarify mecha.nism of LCX001.RESULTS LCX001 effectively rescued and prevented opioid(fentanyl and TH-030418),propofol,and pentobarbital-induced respiratory depression by strengthening respiratory fre.quency and minute ventilation in rats.The acetic acid writhing test and hot-plate test revealed potent anti-nociceptive efficacy of LCX001,in contrast to some ampakines that did not affect analgesia.Fur.thermore,LCX001 potentiated [3 H]AMPA and L-glutamate binding affinity to AMPA receptors,and facili.tated glutamate-evoked inward currents in HEK293 cells stably expressing GluA2(R).Importantly,appli.cation of LCX001 generated a significant increase in GluA2(R) surface expression in a mechanism of stargazin up-regulation,and restrained opioid-induced abnormal intracellular Ca^(2+) load,which might par.ticipate in breathing modulation.CONCLUSION The novel pharmacological effect and potential new mechanism of LCX001 might promote ampakines to be a therapeutic option for protection against respi.ratory depression. 展开更多
关键词 麻醉药 镇静催眠药 临床分析 治疗方法
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Study on the Allosteric Modulators of Muscarinic M_2-Receptors: Synthesis of Unsymmetrical Analogous of W84
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作者 RuntaoLi UlrikeHolzgrabe 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期450-450,共1页
关键词 Study on the Allosteric modulators of Muscarinic M2-Receptors Synthesis of Unsymmetrical Analogous of W84
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Study on the Allosteric Modulators of Muscarinic M_2-Receptors Ⅱ: Synthesis of W84 Analogous with PiperazinylDithiocarbonate
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作者 RuntaoLi UlrikeHolzgrabe 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期451-451,共1页
关键词 Study on the Allosteric modulators of Muscarinic M2-Receptors Synthesis of W84 Analogous with PiperazinylDithiocarbonate
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面向电力通信的Delta-sigma调制高可靠传输研究
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作者 张俊 芮文君 吕娜 《光通信研究》 北大核心 2025年第1期29-34,共6页
【目的】电力通信专网用于电力系统的调度、运营和管理,其重要特点是高度的可靠性和实时性。当前电力通信专网的典型中继距离为40 km,为了进一步提升其可靠性,可以增加单光口传输距离和减少光放大器数量,从而减少潜在故障点。【方法】... 【目的】电力通信专网用于电力系统的调度、运营和管理,其重要特点是高度的可靠性和实时性。当前电力通信专网的典型中继距离为40 km,为了进一步提升其可靠性,可以增加单光口传输距离和减少光放大器数量,从而减少潜在故障点。【方法】文章提出了一种基于Delta-sigma调制的高保真度数字传输方法,在发射端利用过采样、噪声整形和两电平量化等方法,将原始高阶调制信号转化成正交相移键控(QPSK)的光域波形,以大幅提升传输过程中对链路噪声和非线性的抵抗能力。在接收端通过符号判决移除链路噪声,再利用低通滤波器消除整形后的带外量化噪声,最终实现原始信号的低复杂度解调。【结果】在验证性离线实验中,经过160 km标准单模光纤的无中继传输和相干检测后,50 GBaud偏振复用QPSK光域波形可以实现无误码传输。解调后的原始高阶调制信号在9倍过采样下,恢复信噪比(SNR)可以达到33.0 dB,达到32.0 dB的SNR门限,能够支持1024进制正交幅度调制(1024-QAM)信号的高保真传输,单波长比特率为111 Gbit/s。【结论】实验结果表明,Delta-sigma调制方案能够以带宽展宽获取SNR提升,从而有效拓展传输跨距和传输性能,为下一代低成本和高可靠性电力专网提供了潜在的解决方案。 展开更多
关键词 电力通信 delta-sigma调制 相干检测 无中继传输 信噪比
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Taming of trinitromethyl-oxadiazole to access high density and high oxygen balance via a dual modulation strategy
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作者 Jinya Zhang Teng Fei +4 位作者 Jingwei Meng Jinxiong Cai Lei Zhang Siping Pang Chunlin He 《Defence Technology(防务技术)》 2025年第1期142-149,共8页
Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involv... Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive performance.Utilizing this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic compounds.Notably,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),respectively.Additionally,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and stability.This work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials. 展开更多
关键词 Energetic materials High oxygen balance High density Dual modulation Trinitromethyl group
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Generalized multiple-mode prolate spheroidal wave functions multi-carrier waveform with index modulation
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作者 XU Zhichao LU Faping +5 位作者 ZHANG Lifan YANG Dongkai LIU Chuanhui KANG Jiafang AN Qi ZHANG Zhilin 《Journal of Systems Engineering and Electronics》 2025年第2期311-322,共12页
A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The p... A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The proposed method,based on the optimized multi-index modulation, does not limit the number of signals in the first and second constellations and abandons the concept of limiting the number of signals in different constellations. It successfully increases the spectrum efficiency of the system while expanding the number of modulation symbol combinations and the index dimension of PSWFs signals. The proposed method outperforms the PSWFs multi-carrier index modulation method based on optimized multiple indexes in terms of spectrum efficiency, but at the expense of system computational complexity and bit error performance. For example, with n=10 subcarriers and a bit error rate of 1×10^(-5),spectral efficiency can be raised by roughly 12.4%. 展开更多
关键词 prolate spherical wave function(PSWF) generalized multiple-mode index modulation spectral efficiency.
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一种24位Delta-Sigma A/D数字抽取滤波器设计 被引量:5
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作者 骆丽 李晓玥 +1 位作者 曾俊琦 徐子轩 《北京交通大学学报》 CAS CSCD 北大核心 2016年第5期45-49,共5页
为了可以对天文望远镜环境温度实现更好的监控,本文设计了一种针对天文望远镜温度监控的24位高精度Delta-Sigma(简称D-S)A/D数字抽取滤波器,主要工作包括D-S A/D数字抽取滤波器Matlab建模与仿真、Verilog代码编写和使用SMIC18工艺的数... 为了可以对天文望远镜环境温度实现更好的监控,本文设计了一种针对天文望远镜温度监控的24位高精度Delta-Sigma(简称D-S)A/D数字抽取滤波器,主要工作包括D-S A/D数字抽取滤波器Matlab建模与仿真、Verilog代码编写和使用SMIC18工艺的数字后端设计.其中有限冲击响应(FIR)抽取滤波器共3级:第1级为级联积分梳状(CIC)滤波器,抽取因子为32;第2级为级联积分梳状补偿滤波器,抽取因子为16;第3级为半带(HB)滤波器,抽取因子为2.最后设计的滤波器的输入信号为4位,采样频率4.096 MHz,输出信号24位,采样频率4kHz,输出信噪比154dB.得到的输出波形满足设计要求. 展开更多
关键词 delta-sigma A/D 数字抽取滤波器 24位 版图
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一种用于差分电容检测的电荷Delta-Sigma调制器的研究 被引量:3
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作者 王展飞 李志宏 《传感技术学报》 CAS CSCD 北大核心 2006年第05B期2252-2254,2259,共4页
研究一种用于差分电容传感器检测的电荷Delta-Sigma调制器结构.在该检测电路中不需要C/V转换电路,待检测的差分电容直接作为调制器环路的输入电容,差分电容的变化量首先被转换为变化的电荷,然后被调制成一位的数字输出信号.文章最后给... 研究一种用于差分电容传感器检测的电荷Delta-Sigma调制器结构.在该检测电路中不需要C/V转换电路,待检测的差分电容直接作为调制器环路的输入电容,差分电容的变化量首先被转换为变化的电荷,然后被调制成一位的数字输出信号.文章最后给出了一个二阶的Delta-Sigma调制器的行为级仿真结果. 展开更多
关键词 电容检测 delta-sigma 电容传感器
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Delta-Sigma A/D转换器原理及其PSpice仿真 被引量:4
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作者 陈拓 刘铮 《现代电子技术》 2011年第16期119-122,共4页
为了深入理解Delta-Sigma A/D转换器的工作原理,合理地使用这类A/D转换器产品,或者用FPGA实现自己的Delta-Sigma A/D转换器设计。采用PSpice仿真软件进行模拟仿真的方法,对不同幅度的输入信号进行了一阶Delta-Sig-ma A/D转换器仿真实验... 为了深入理解Delta-Sigma A/D转换器的工作原理,合理地使用这类A/D转换器产品,或者用FPGA实现自己的Delta-Sigma A/D转换器设计。采用PSpice仿真软件进行模拟仿真的方法,对不同幅度的输入信号进行了一阶Delta-Sig-ma A/D转换器仿真实验,获得了与理论相一致的结果。通过对元件的参数扫描仿真为实际电路设计中元件的选择提供了实验依据。仿真实验过程完整,易于重复,与纯数学推导相比,仿真具有直观的特点。 展开更多
关键词 delta-sigma A/D转换器 过采样 PSPICE仿真
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On minimal quasi-injective modules and strong Kasch modules 被引量:2
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作者 朱占敏 张小向 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2009年第3期243-248,253,共7页
设R为一个环,M为一个右R-模.若每个从M的单子模到M的同态都可以开拓为M的自同态,则称M为一个极小拟内射模.若每个单的右R-模都可以嵌入M,则称M为一个强Kasch模.本文研究了这两类模的一些刻画和性质.
关键词 极小拟内射模 强Kasch模 半完全环 半局部环
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基于串联型DC module的光伏发电系统研究 被引量:3
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作者 张琦 孙向东 +2 位作者 钟彦儒 吴迎丰 张凯 《西安理工大学学报》 CAS 北大核心 2009年第4期410-414,共5页
提出了一种基于串联型直流功率单元(DC module)电路的光伏发电系统,讨论了采用单端反激变换器实现的DC module电路。由于反激变换器用于升压变换时变压器原边电流较大,当并联使用时效率较低,为了减小DC module电路升压压力,提高每组变... 提出了一种基于串联型直流功率单元(DC module)电路的光伏发电系统,讨论了采用单端反激变换器实现的DC module电路。由于反激变换器用于升压变换时变压器原边电流较大,当并联使用时效率较低,为了减小DC module电路升压压力,提高每组变换器能量传输效率,采用串联形式的DC module电路,且每组DC module电路使用独立的最大功率追踪算法,由此组成的光伏发电系统提高了DC module电路的升压效率,且可以实现每块光伏电池板的最大功率点跟踪,解决了不同光照(阴影)、不同规格以及不同朝向等因素引起的失配问题。实验结果表明,当一路或多路电路中的电池板受到阴影影响时,各路电池板在控制器的作用下仍然工作在各自的最大功率点处。 展开更多
关键词 直流功率单元 单端反激变换器 光伏发电系统
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多位数字delta-sigma调制器的设计
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作者 杨文荣 程媛媛 《电子测量技术》 2007年第5期11-13,共3页
本文介绍了一个高信噪比的、用在24位44.1kHz采样率的音频数/模转换器(DAC)中的4阶15级量化的delta-sigma调制器(DSM)。在设计中,为了减少量化噪声,选用了奇数个量化等级;为了提高动态范围(DR),在设计噪声传输函数(NTF)时对零点进行优化... 本文介绍了一个高信噪比的、用在24位44.1kHz采样率的音频数/模转换器(DAC)中的4阶15级量化的delta-sigma调制器(DSM)。在设计中,为了减少量化噪声,选用了奇数个量化等级;为了提高动态范围(DR),在设计噪声传输函数(NTF)时对零点进行优化,通过这些方法降低量化噪声和时钟抖动的影响。这个DSM的峰值信噪比(SNR)可以达到130dB以上,满足0.35μmCMOS工艺设计的音频DAC的系统要求。本文给出了这个DSM的MATLAB仿真模型及仿真结果,并在此基础上给出了电路实现结构。 展开更多
关键词 delta-sigma调制器 数模转换器 量化 过采样
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Markov-modulated风险模型破产前最大盈余额与破产赤字的联合分布 被引量:2
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作者 董继国 刘国欣 《高校应用数学学报(A辑)》 CSCD 北大核心 2010年第1期9-12,共4页
应用逐段决定马尔可夫过程理论及补充变量技巧,使Markov-modulated风险过程成为齐次强马尔可夫过程,然后利用强马氏性及首达时间分布给出了其破产前最大盈余额与破产赤字的联合分布.
关键词 Markov-modulated风险模型 逐段决定马尔可夫过程 补充变量
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基于STM32的Delta-Sigma调制的鱼探仪发射机信号源设计 被引量:8
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作者 陈继华 吴晨昺 谌志新 《仪器仪表学报》 EI CAS CSCD 北大核心 2016年第S1期67-73,共7页
在鱼探仪发射机的信号源设计中提出了一种基于STM32的Delta-Sigma调制的D类软件可调幅正弦波的设计方法。采用MATLAB的DSToolbox工具箱设计了2阶过采样率为40的2值Delta-Sigma调制器,并在STM32中软件实现。分析了影响源输出的诸多因素,... 在鱼探仪发射机的信号源设计中提出了一种基于STM32的Delta-Sigma调制的D类软件可调幅正弦波的设计方法。采用MATLAB的DSToolbox工具箱设计了2阶过采样率为40的2值Delta-Sigma调制器,并在STM32中软件实现。分析了影响源输出的诸多因素,如死区、电源纹波、调制比;对电路设计和布板给出了建议。该方法可灵活方便地扩展设计任意波形,对于各类仪器仪表,如超声波探测仪、信号发生器、测量仪表、EMC抗干扰度模拟发生器等的信号源设计具有极大的参考价值。 展开更多
关键词 STM32 delta-sigma调制器 MATLAB DSToolbox工具箱 鱼探仪 发射机
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Delta-Sigma调制器在空间指向镜位置伺服系统中的应用 被引量:2
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作者 王淳 谢妮慧 林喆 《航天返回与遥感》 2014年第5期54-60,共7页
在目前的空间指向镜位置伺服系统中,数字控制器输出脉宽调制(PWM)的量化误差会导致指向出现小幅角度振荡,使得指向的稳定性降低,进而导致光学遥感成像质量发生退化。针对航天器工程实现的特点,将Delta-Sigma调制器引入到数控软件中,在... 在目前的空间指向镜位置伺服系统中,数字控制器输出脉宽调制(PWM)的量化误差会导致指向出现小幅角度振荡,使得指向的稳定性降低,进而导致光学遥感成像质量发生退化。针对航天器工程实现的特点,将Delta-Sigma调制器引入到数控软件中,在不改变硬件电路与系统参数的前提下,显著的降低了输出量化误差对伺服系统的影响。Matlab仿真结果表明,该方法可使指向镜的指向角度振荡幅值衰减至原来的1/5以下,有效地提高了指向镜的指向稳定性。 展开更多
关键词 三角积分调制器 指向镜 伺服系统 量化 空间遥感
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