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Type division and controlling factor analysis of 3rd-order sequences in marine carbonate rocks 被引量:1
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作者 Yunbo Zhang Zongju Zhao +4 位作者 Genhou Wang Zaixing Jiang Mingjian Wang Min Zheng Shiben Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期289-298,共10页
Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehens... Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehensive analysis of carbon and oxygen isotope trends, paleobathymetry and spectral-frequency of representative well logs, 3rd-order sequences can be divided into 3 types: (a) global sea level (GSL) sequence mainly controlled by GSL change;(b) tectonic sequence mainly controlled by regional tectonic activity;and (c) composite sequence jointly controlled by GSL change and regional tectonic activity. This study aims to identify the controlling factors of 3rd-order sequences and to illustrate a new method for classification of 3rd-order sequences of the middle Permian strata in the Sichuan Basin, China. The middle Permian strata in the Sichuan Basin consist of 3 basin-contrastive 3rd-order sequences, i.e., PSQ1, PSQ2 and PSQ3. Of these, PSQ1 is a GSL sequence while PSQ2 and PSQ3 are composite sequences. The results suggest that the depositional environment was stable during the deposition of PSQ1, but was activated by tectonic activity during the deposition of the middle Permian Maokou Formation. 展开更多
关键词 Carbon isotope 3rd-order sequence Milankovitch cycles Middle Permian strata Sichuan Basin
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2进1出3 dB宽带定向耦合器的设计 被引量:1
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作者 汪海英 江海金 《电子科技》 2017年第8期131-133,共3页
基于平行耦合线的理论,研究了2进1出3dB宽带定向耦合器的设计原理及方法。根据理论计算及电路仿真,采用三节耦合线,结合耦合带状线上下空间结构,进行三维建模仿真,优化低互调大功率负载。通过实物加工和调试,获得了工作带宽内驻波比<... 基于平行耦合线的理论,研究了2进1出3dB宽带定向耦合器的设计原理及方法。根据理论计算及电路仿真,采用三节耦合线,结合耦合带状线上下空间结构,进行三维建模仿真,优化低互调大功率负载。通过实物加工和调试,获得了工作带宽内驻波比<1.15、耦合度<3.4dB、隔离度>30dB、三阶互调<-160dBc的结果,能较好地满足实际工程需要。 展开更多
关键词 定向耦合器 耦合带状线 三阶互调 3 DB
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移动通信(3G)的发展与射频同轴电缆 被引量:1
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作者 李恩铭 《现代有线传输》 2005年第5期52-55,共4页
本文阐述了移动通信,特别是第三代移动通信的发展,分析了射频同轴电缆的结构、特点及生产制遣,探讨了适应第三代移动通信网络建设性能要求的射频同轴电缆的工艺改进问题。
关键词 移动通信 3G技术 射频同轴电缆 网络建设 驻波比
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地铁通信系统中的新型多系统合路平台设计与应用 被引量:1
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作者 李安庆 江晋剑 《安庆师范大学学报(自然科学版)》 2018年第4期50-58,共9页
针对地铁4G移动通信覆盖方案,设计了一款10进2出POI系统,实现了LTE与2/3G多系统的信号合路传输。该系统具有合路损耗小、端口隔离度高、带外抑制度高、功率容量大、高温度稳定性和三阶互调低等特点,能够避免系统间的相互干扰。另外,POI... 针对地铁4G移动通信覆盖方案,设计了一款10进2出POI系统,实现了LTE与2/3G多系统的信号合路传输。该系统具有合路损耗小、端口隔离度高、带外抑制度高、功率容量大、高温度稳定性和三阶互调低等特点,能够避免系统间的相互干扰。另外,POI器件具有体积小、性能高且满足低成本、易量产等优势。 展开更多
关键词 地铁 多系统合路平台 三阶互调 3dB电桥
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Nonlinear Optical Response of nc-Si-SiO2 Films Studied with Femtosecond Four-Wave Mixing Technique 被引量:3
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作者 郭亨群 王启明 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第11期2989-2992,共4页
Nonlinear optical properties of silicon nanocrystals (nc-Si) embedded in SiO2 films are investigated using timeresolved four-wave mixing technique with a femtosecond laser. The off-resonant third-order nonlinear sus... Nonlinear optical properties of silicon nanocrystals (nc-Si) embedded in SiO2 films are investigated using timeresolved four-wave mixing technique with a femtosecond laser. The off-resonant third-order nonlinear susceptibility X^(3) is observed to be 1.3×10^-10 esu at 800nm. The relaxation time of the film is fast as short as 50fs. The off-resonant nonlinearity is predominantly electronic in origin and enhanced due to quantum confinement. 展开更多
关键词 3rd-order TIME GAAS
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一种星载天线金属网PIM性能的波导测试方法
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作者 崔镇 马小飞 +3 位作者 施锦文 李维梅 周兰兰 彭健 《太赫兹科学与电子信息学报》 2023年第3期286-290,共5页
金属网的无源互调(PIM)是大功率星载网状天线的一项重要性能参数。传统的金属网无源互调测试主要采用空间辐射法,但空间辐射法需要的金属网样件尺寸大,测试效率低。对此,提出一种基于三端口模块波导测试系统的金属网无源互调性能测试方... 金属网的无源互调(PIM)是大功率星载网状天线的一项重要性能参数。传统的金属网无源互调测试主要采用空间辐射法,但空间辐射法需要的金属网样件尺寸大,测试效率低。对此,提出一种基于三端口模块波导测试系统的金属网无源互调性能测试方法。为验证测试方法的有效性,搭建了基于三端口模块的金属网PIM性能测试系统,并对传统型和改进型2个金属网样件进行了PIM性能测试。测试结果表明,改进后的金属网PIM性能提升了50 dB以上。本文提出的金属网PIM性能测试方法使用的三端口测试系统集成度高,性能稳定,系统搭建效率高。相比传统的空间辐射测试法,本文方法的测试样件尺寸减小了一个数量级,为快速研究新型低PIM金属网提供了有力支持。 展开更多
关键词 星载天线 金属网 无源互调 测试 三端口波导法
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The 3rd-order nonlinearity of bacteriorhodopsin by four-wave mixing 被引量:1
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作者 HUANG Yanping WANG Liying +2 位作者 CHEN Shudi WANG Zugeng LI Qingguo 《Chinese Science Bulletin》 SCIE EI CAS 2000年第19期1752-1755,共4页
The 3rd-order nonlinear optical susceptibility x(3) and the response time of the light-transducing biomolecule bacteriorhodopsin were measured with the four-wave mixing technique and a picosecond frequency-doubled Nd:... The 3rd-order nonlinear optical susceptibility x(3) and the response time of the light-transducing biomolecule bacteriorhodopsin were measured with the four-wave mixing technique and a picosecond frequency-doubled Nd: YAG laser (532 nm). The x(3) and the response time measured are 10-9 esu and 20 ps , respectively. The possible mechanism for generating the 3rd-order nonlinear optical susceptibility x(3) and response time were discussed. 展开更多
关键词 BACTERIORHODOPSIN 3rd-order NONLINEARITY four-wave MIXING light-transducing BIOMOLECULE response time.
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Third Order Adjoint Sensitivity and Uncertainty Analysis of an OECD/NEA Reactor Physics Benchmark: III. Response Moments 被引量:3
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作者 Ruixian Fang Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第4期559-570,共12页
The (180)<sup>3</sup> third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental benchmark with respect to the benchmark’s 180 microscopic total cros... The (180)<sup>3</sup> third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental benchmark with respect to the benchmark’s 180 microscopic total cross sections have been computed in accompanying works [1] [2]. This work quantifies the contributions of these (180)<sup>3</sup> third-order mixed sensitivities to the PERP benchmark’s leakage response distribution moments (expected value, variance and skewness) and compares these contributions to those stemming from the corresponding first- and second-order sensitivities of the PERP benchmark’s leakage response with respect to the total cross sections. The numerical results obtained in this work reveal that the importance of the 3<sup>rd</sup>-order sensitivities can surpass the importance of the 1<sup>st</sup>- and 2<sup>nd</sup>-order sensitivities when the parameters’ uncertainties increase. In particular, for a uniform standard deviation of 10% of the microscopic total cross sections, the 3<sup>rd</sup>-order sensitivities contribute 80% to the response variance, whereas the contribution stemming from the 1st- and 2nd-order sensitivities amount only to 2% and 18%, respectively. Consequently, neglecting the 3<sup>rd</sup>-order sensitivities could cause a very large non-conservative error by under-reporting the response variance by a factor of 506%. The results obtained in this work also indicate that the effects of the 3<sup>rd</sup>-order sensitivities are to reduce the response’s skewness in parameter space, rendering the distribution of the leakage response more symmetric about its expected value. The results obtained in this work are the first such results ever published in reactor physics. Since correlations among the group-averaged microscopic total cross sections are not available, only the effects of typical standard deviations for these cross sections could be considered. Due to this lack of correlations among the cross sections, the effects of the <em>mixed</em> 3<sup>rd</sup>-order sensitivities could not be quantified exactly at this time. These effects could be quantified only when correlations among the group-averaged microscopic total cross sections would be obtained experimentally by the nuclear physics community. 展开更多
关键词 Polyethylene-Reflected Plutonium Sphere 3rd-order Sensitivities 1st-Order 2nd-Order and 3rd-order Uncertainty Analysis Microscopic Total Cross Sections Expected Value Variance and Skewness of Response Distribution
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新型内置合路器天线仿真与设计 被引量:1
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作者 张帅 《电子设计工程》 2017年第18期131-133,138,共4页
随着移动通信的发展,为了满足通信市场的需求,提出了一种能满足4G频段的合路器天线。采用内置合路器的方法使天线能工作在不同频段的同时,优化了天线的尺寸,减少了损耗。本文使用HFSS电磁仿真软件对天线阵列进行仿真分析,利用awr软件对... 随着移动通信的发展,为了满足通信市场的需求,提出了一种能满足4G频段的合路器天线。采用内置合路器的方法使天线能工作在不同频段的同时,优化了天线的尺寸,减少了损耗。本文使用HFSS电磁仿真软件对天线阵列进行仿真分析,利用awr软件对天线指标进行优化。实际天线驻波互调稳定,装配简单,指标基本满足要求。 展开更多
关键词 天线 合路器 3阶互调 HFSS 驻波
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A Sign Alternation of Nonlinear Absorption in Gold Composite Films in Z-Scan
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作者 陈代坚 丁沙 +4 位作者 韩俊波 周慧君 肖思 熊贵光 王取泉 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第9期2286-2289,共4页
Au-TiO2 composite films with Au atom content varying from about 15% to 82% are prepared by co-sputtering technique. Both open- and closed-aperture Z-scan of the samples are performed in the femtosecond time region. A ... Au-TiO2 composite films with Au atom content varying from about 15% to 82% are prepared by co-sputtering technique. Both open- and closed-aperture Z-scan of the samples are performed in the femtosecond time region. A conversion of the nonlinear absorption from negative to positive is observed as the A u atom content increases due to the saturation of reverse saturable absorption. The nonlinear refractive index γ and effective nonlinear absorption coefficient βeff at the Au atom content of 54% are measured to be 1.6 × 10^-2 cm^2/GW and -2.6 ×10^3 cm/GW, respectively. The corresponding third-order optical nonlinearity X^(3) is about 6.3 × 10^-8 esu. 展开更多
关键词 3rd-order OPTICAL NONLINEARITY THIN-FILMS SINGLE-BEAM THRESHOLD POLYMER SILVER
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Fifth-Order Comprehensive Adjoint Sensitivity Analysis Methodology for Nonlinear Systems (5th-CASAM-N): I. Mathematical Framework 被引量:1
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2022年第1期44-78,共35页
This work presents the mathematical framework of the “Fifth-Order Comprehensive Adjoint Sensitivity Analysis Methodology for Nonlinear Systems (5<sup>th</sup>-CASAM-N),” which generalizes and extends all... This work presents the mathematical framework of the “Fifth-Order Comprehensive Adjoint Sensitivity Analysis Methodology for Nonlinear Systems (5<sup>th</sup>-CASAM-N),” which generalizes and extends all of the previous works performed to date on this subject. The 5<sup>th</sup>-CASAM-N enables the exact and efficient computation of all sensitivities, up to and including fifth-order, of model responses to uncertain model parameters and uncertain boundaries of the system’s domain of definition, thus enabling, inter alia, the quantification of uncertainties stemming from manufacturing tolerances. The 5<sup>th</sup>-CASAM-N provides a fundamental step towards overcoming the curse of dimensionality in sensitivity and uncertainty analysis. 展开更多
关键词 Nonlinear Models of Physical Systems High-Order Sensitivity Analysis 1st-Order Sensitivities 2nd-Order Sensitivities 3rd-order Sensitivities 4th-Order Sensitivities 5th-Order Sensitivities
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接收机三阶截点原理分析及测试方法探讨 被引量:1
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作者 郭锋 《上海计量测试》 2008年第3期20-23,共4页
介绍接收机存在的两种互调失真及其测试方法,针对最新数字超短波接收机的技术特点,提出一种实用的三阶截点测试方法,并分析该方法的测试原理。
关键词 三阶截点 互调失真 中频带宽 数字接收机 中频滤波器
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Carbon and oxygen isotope variation and its implication for marine sequence: A case study of Ordovician in Tarim Basin 被引量:3
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作者 Zongju Zhao Jianguo Wang Peixi Wang 《Petroleum Research》 2017年第3期281-290,共10页
Carbon and oxygen isotopes of marine carbonate rocks or fossil shells could indicate global sea-level relative change.Generally,heavier carbon isotopes or lighter oxygen isotopes reflected rise of global sea-level rel... Carbon and oxygen isotopes of marine carbonate rocks or fossil shells could indicate global sea-level relative change.Generally,heavier carbon isotopes or lighter oxygen isotopes reflected rise of global sea-level relative changes,and vice versa.For carbonate rocks deposited before Tertiary,carbon isotope was more stable than oxygen isotope,and thus it was more suitable to indicate global sea-level relative fluctuation.Within time limit of the 3rd-order sequence(1-10Ma),large scale migration of carbonate platforms would not occur and carbonate productivity would not change greatly,therefore,a research method of marine tectonic sequence(i.e,a contrastive analysis method of carbon and oxygen isotopessedimentary cycles)was proposed.Thus,the marine 3rd-order sequences were divided the global sealevel sequence which was controlled by global sea-level change and the tectonic sequence which was controlled by regional tectonic subsidence and uplift.The global sea-level fluctuation indicated by carbon and oxygen isotopes were consistent with variation of sedimentary cycles and water depth of the global sea-level sequence,but were not consistent with variation of sedimentary cycles and water depth of the tectonic sequence.As a case study of Ordovician in Tarim Basin,two 3rd-order global sea-level sequences were identified in the Lower Ordovician,while six 3rd-order tectonic sequences controlled by collision and compression between Arkin island arc,Kudi active continental margin uplift and Tarim Plate were identified in the Middle and Upper Ordovician.Particularly,OSQ6 in the Upper Ordovician(Lianglitage Formation)was a typical tectonic sequence. 展开更多
关键词 The global sea-level sequence The tectonic sequence The 3rd-order sequence Carbon and oxygen isotope Lianglitage Formation ORDOVICIAN Tarim Basin
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