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A Comparative Study on Chinese and American Views of Time
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作者 周海霞 《海外英语》 2013年第14期286-288,共3页
This paper focuses on people's attitude towards time and the reason. In addition, it discusses the cultural implication behind. Through the writing of this paper, readers are able to find out the reasons for the c... This paper focuses on people's attitude towards time and the reason. In addition, it discusses the cultural implication behind. Through the writing of this paper, readers are able to find out the reasons for the conception and behavior conflicts that you might have encountered in your communication. The aim of this paper is to help readers to decrease the chance or avoid of conflicts caused by time views in intercultural communication. 展开更多
关键词 ATTITUDE time views COMMUNICATION
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On the Feminist Comparative Study of Views on Marriage Between the Early Nineteenth Century and Modern Times—Taking Pride and Prejudice for Example
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作者 张平 《海外英语》 2016年第9期176-178,共3页
Marriage is a theme influenced by cultural progress. Economic factor is one of the main elements that people of the early nineteenth century considered when deciding a marriage. The pursuit of economic interest result... Marriage is a theme influenced by cultural progress. Economic factor is one of the main elements that people of the early nineteenth century considered when deciding a marriage. The pursuit of economic interest results in the advent of some tragic marriages while now it is a side reason. However, women today have made great advancement in education background, employment situation and social status. Women gradually have their economic ability, autonomy and social status. Hence, they began to lay emphasis on the equality and sense of happiness. This is why the views on marriage vary in different eras. This paper, based on the view of marriage from the nineteenth- century English novel Pride and Pejudice, is dedicated to elucidating the changes and improvements of view on marriage from feminist perspective via comparing and contrasting the similarities and the differences of people's view on marriage between the early 1800 s and modern times, and then draws a conclusion that the women's degree of receptive education can influence their social status and view on marriage. In modern times the view on marriage based on equality attribute to the sense of happiness of a family and the degree of satisfaction of marriage. 展开更多
关键词 the EARLY 1800s modern times view on MARRIAGE FEMINIST perspective SIMILARITIES differences degree o
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Capsule endoscopy: Improving transit time and image view 被引量:25
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作者 Zvi Fireman D Paz Y Kopelman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5863-5866,共4页
AIM: To evaluate the effect of various methods of small bowel preparation on the transit time and the quality of visualization of the entire small bowel mucosa. METHODS: Ninety-five patients underwent capsule endosc... AIM: To evaluate the effect of various methods of small bowel preparation on the transit time and the quality of visualization of the entire small bowel mucosa. METHODS: Ninety-five patients underwent capsule endoscopy (CE) by easily swallowing the capsule. They were divided into three study groups according to the preparation used: group A (n = 26) by polyethylene glycol (PEG) liter or with sodium phosphate (SP) 12 h prior to the CE study; group B (n = 29) by erythromycin 1 h prior to the CE study; and group C (n = 40) without any preparation. Visualization ranged from good to satisfactory to poor. RESULTS: The gastric emptying time in the group prepared with erythromycin was shorter but without statistical significance and the small bowel transit time was unaffected. In elderly subjects prepared by PEG or SP, the gastric emptying time was significantly longer (163.7 rain, P = 0.05). The transit times of the three sub-groups were not affected by gender or pathology. The grade of cleaning of the entire study group was 3.27±1.1. The erythromycin group presented significantly the worst quality of images (P = 0.05) compared to the other sub-groups. Age, gender, and pathology had no effect on the quality of the cleaning of the small bowel in the sub-groups. One (1.05%) case had no natural excretion. CONCLUSION: Erythromycin markedly reduces gastric emptying time, but has a negative effect on the quality of the image in the small bowel. The preparation of elderly subjects with PEG or SP has a negative effect on the small bowel transit time. 展开更多
关键词 Capsule endoscopy Gastric emptying time Small bowel transit time view ERYTHROMYCIN Polyethylene glycol
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Calculation of Taper Rolling Time in Plan View Pattern Control Process 被引量:2
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第5期1-3,共3页
The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper... The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper thickness can be obtained. The numerical solution for this formula was used on site. According to the simulation result, the roll gap value should be changed linearly with rolling time. 展开更多
关键词 plan view pattern control forward slip model TAPER time calculation
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Comparison between the Chinese time view and the western view
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作者 LIU He-jun 《Sino-US English Teaching》 2008年第11期60-64,共5页
The difference between the Chinese time view and the western time view originates from agricultural civilization's inertia and industrial civilization's feeling way. This time coordinate controls people's behavior,... The difference between the Chinese time view and the western time view originates from agricultural civilization's inertia and industrial civilization's feeling way. This time coordinate controls people's behavior, awareness of concepts, industrial relationship, interpersonal relationship and value orientation. Different cultures bred different time conceptions and time behaviors. This paper mainly talks about the aspects of their differences. When different time views are reflected in cross-cultural communication, conflicts and obstacles of interpersonal communication may arise. With the development of social economy and cultural communication, the time views of Chinese culture and western culture have impacts on each other and are gradually integrated with each other. 展开更多
关键词 view on time cultural difference cross-cultural communication FUSION
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High Accuracy and Real-Time Gated Viewing Laser Radar
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作者 Dong Li Hua-Jun Yang Shan-Pei Zhou 《Journal of Electronic Science and Technology》 CAS 2011年第3期261-264,共4页
A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according... A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according to the demand for real-time imaging is presented, and then the simulation is used to analyze the performance of the real-time gated viewing system. The range accuracy performance is limited by the slice number, the width of gate, the delay time step, the initial delay time, as well as the system noise and atmospheric turbulence. The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters. Finally, how to choose the optimal parameters has been researched. 展开更多
关键词 Index Terms Gated viewing range accuracy real-time laser radar target detection.
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The LabVIEW Simulation of Space-Time Coding Technique in the MIMO-OFDM System
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作者 Jiancai Liu Shutin Chen Jiakai Xu 《遥感科学(中英文版)》 2013年第1期9-14,共6页
关键词 MIMO-OFDM系统 空时编码技术 LABview MIMO系统 V-BLAST 空时分组码 仿真 软件模拟
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Analysis of Viewing Paintings from the Perspective of Iconography
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作者 Min Li 《Journal of Contemporary Educational Research》 2024年第7期297-303,共7页
Distinguished from purely formalistic research methods,iconography pursues the interpretation of the hidden historical and humanistic connotations behind artworks,and is a discipline that combines visual text and cont... Distinguished from purely formalistic research methods,iconography pursues the interpretation of the hidden historical and humanistic connotations behind artworks,and is a discipline that combines visual text and content analysis methods.Combining the three stages of iconography proposed by Panofsky,the paper studies Shizeng Chen’s Viewing Paintings from the perspective of iconography,summarizing the formation and change of the images and contents of the artworks in the cultural system and civilization at that time,as well as their implied ideology,and analyzing the hidden spirit of the times and the historical significance behind them,so as to expound their iconographic significance.Through an in-depth discussion at three levels:pre-pictorial iconographic description,iconographic analysis,and iconographic interpretation,the facts and surface contents reproduced in the images,the traditional level of literary,artistic,and cultural knowledge,as well as the interpretation of the potential meanings are revealed. 展开更多
关键词 ICONOGRAPHY viewing Paintings Spirit of the times Conceptual change
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iViewer:利用数据服务即时生成跨域数据视图 被引量:4
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作者 温彦 刘晨 韩燕波 《计算机科学与探索》 CSCD 2012年第3期221-236,共16页
越来越多的企业和组织选择通过广域、开放的互联网作为其协作平台,业务决策者往往需要即时汇聚并综合分析来自多个部门的资源信息以进行临机决策。如何即时构建满足用户需求的跨组织数据视图,动态维护视图和数据源之间的一致性是需要求... 越来越多的企业和组织选择通过广域、开放的互联网作为其协作平台,业务决策者往往需要即时汇聚并综合分析来自多个部门的资源信息以进行临机决策。如何即时构建满足用户需求的跨组织数据视图,动态维护视图和数据源之间的一致性是需要求解的一个关键问题。提出了一种互联网环境下跨组织业务数据视图的动态生成方法iViewer,利用数据服务来封装自治、异构和动态变化的数据源;通过可视化和易用的数据服务组合操作来动态构建数据视图;提出了一种基于轮询的视图动态更新算法,维护数据源和数据视图的一致性,从而使得数据视图能够随数据源的变化而自主变化;详述了iViewer方法的原理和过程,并通过一个火灾应急处置场景中,面向指挥中心的跨部门火灾救援设备数据视图的动态生成过程例证了iViewer方法的效果。 展开更多
关键词 数据服务 数据视图 跨组织数据 即时构建 视图维护
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WebView在线物化选择方案的研究 被引量:4
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作者 张欣 陈峰 乐嘉锦 《计算机研究与发展》 EI CSCD 北大核心 2004年第10期1629-1633,共5页
随着Internet的高速发展 ,产生了海量的Web信息 ,其中动态网页占了很大的部分 WebView是指通过数据查询所产生的HTML或者XML文件块 ,对WebView进行物化可以提高用户的查询速度 ,但是其代价是会可能为用户提供过期的数据 定义了WebView... 随着Internet的高速发展 ,产生了海量的Web信息 ,其中动态网页占了很大的部分 WebView是指通过数据查询所产生的HTML或者XML文件块 ,对WebView进行物化可以提高用户的查询速度 ,但是其代价是会可能为用户提供过期的数据 定义了WebView物化模型中的数据质量和服务质量的标准 ,并提出一种在线动态调整的WebView物化选择的算法WMS 。 展开更多
关键词 WEB view 物化视图 数据新鲜度 平均响应时间
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基于FameView的浮选液位控制系统的设计和应用 被引量:6
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作者 严凡涛 王俊鹏 +1 位作者 杨树亮 徐国宏 《有色金属工程》 CAS CSCD 北大核心 2017年第1期49-54,共6页
浮选工艺流程通常由粗选、扫选和精选等流程组成,每个流程配备矿浆液位控制系统用于控制液位的波动,使其稳定。然而,由于这些控制系统相互独立且分散,不能做到集中控制和协同控制,导致控制效果极差,液位波动大。针对这些缺点,北京矿冶... 浮选工艺流程通常由粗选、扫选和精选等流程组成,每个流程配备矿浆液位控制系统用于控制液位的波动,使其稳定。然而,由于这些控制系统相互独立且分散,不能做到集中控制和协同控制,导致控制效果极差,液位波动大。针对这些缺点,北京矿冶研究总院设计了一套浮选机液位控制系统,该系统以PC机和PLC为核心硬件,利用FameView软件作为组态软件,实现了在一个平台上可以控制多套液位控制系统的目的。该系统在陕西某镍矿选矿厂运行半年,控制效果显著,液位波动小,满足生产要求。 展开更多
关键词 FAMEview 浮选液位控制系统 实时监控
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基于LabVIEW的三极管寿命测试系统 被引量:1
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作者 李鹏 高天德 《电子设计工程》 2014年第20期71-74,共4页
针对一些功率器件(功率三极管、VDMOS,IGBT等),通过有规律给元器件通电和断电,循环施加电应力和热应力,可以检验其承受循环应力的能力。基于上述原理,借助可视化编程语言Lab VIEW和NI系列sb RIO-9612板卡,本文设计了一种三极管老化测试... 针对一些功率器件(功率三极管、VDMOS,IGBT等),通过有规律给元器件通电和断电,循环施加电应力和热应力,可以检验其承受循环应力的能力。基于上述原理,借助可视化编程语言Lab VIEW和NI系列sb RIO-9612板卡,本文设计了一种三极管老化测试系统,该系统满足国军标GJB1036的试验要求,每个工位的采样时间不大于4μs,总共64工位的采样周期不大于300μs,满足了快速控制的要求,同时还不失精准,电压和电流的采样分辨率达到了12 bit,精度达到1%,从而控制了器件结温误差。目前系统已经交付运行,实验结果达到了用户的需求,具有很高的实用价值。 展开更多
关键词 LAB view 老化测试 LAB view FPGA 实时
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Key-Time法及其用于时态过滤运算的研究 被引量:2
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作者 蔡启先 《广西工学院学报》 CAS 2005年第2期34-38,共5页
基于C-TRDM时态数据模型,利用传统的关系数据库来进行时态数据处理研究。先提出一种修正关系数据表结构的"Key-Time"法,然后讨论如何基于"Key-Time"法进行单表和多表之间的时态过滤操作,并结合实例加以说明。
关键词 Key-time 时态过滤 时态视图 C-TRDM
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基于C-TRDM模型的Key-Time法与时间过滤算子 被引量:1
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作者 蔡启先 《湖南师范大学自然科学学报》 EI CAS 北大核心 2005年第3期13-17,共5页
基于C-TRDM时态数据模型,利用传统的关系数据库来进行时态数据处理研究,提出一种修正关系数据表结构的“Key-Time”法和时间过滤算子的新概念,讨论了如何基于“Key-Time”法进行单表和多表之间的时间过滤操作,并结合实例给以说明.
关键词 Key-time 时间过滤算子 时态视图 C-TRDM
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基于LabVIEW的多轮对超声探伤系统设计
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作者 吴凡 郭前岗 周西峰 《微型机与应用》 2016年第3期15-17,20,共4页
针对目前车轮检测方法大多以传统手持式人工探伤仪为主的现状,本文在国内某企业现役多通道超声探伤仪硬件结构的基础上设计了一套多轮对超声探伤系统。系统基于Lab VIEW平台,可以实现系统自检、用户信息管理、数据接收、数据分析、显示... 针对目前车轮检测方法大多以传统手持式人工探伤仪为主的现状,本文在国内某企业现役多通道超声探伤仪硬件结构的基础上设计了一套多轮对超声探伤系统。系统基于Lab VIEW平台,可以实现系统自检、用户信息管理、数据接收、数据分析、显示结果、数据存储、自动判伤、输出检测报告等功能。系统采用可变分辨率的数据处理方法,保证了检测过程的实时性及结果的准确性。 展开更多
关键词 多轮对 超声探伤 LABview 实时性
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Impact of random and scattered coincidences from outside of field of view on positron emission tomography/computed tomography imaging with different reconstruction protocols
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作者 Mahak Osouli Alamdari Pardis Ghafarian +2 位作者 Arman Rahmim Mehrdad Bakhshayesh‑Karam Mohammad Reza Ay 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期40-52,共13页
Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outsi... Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outside the field of view(FOV)on PET image quality for different reconstruction protocols.Imaging was performed on the Discovery 690 PET/CT scanner,using experimental configurations including the NEMA phantom(a body phantom,with six spheres of different sizes)with a signal background ratio of 4:1.The NEMA phantom(phantom I)was scanned separately in a one-bed position.To simulate the effect of random and scatter coincidences from outside the FOV,six cylindrical phantoms with various diameters were added to the NEMA phantom(phantom II).The 18 emission datasets with mean intervals of 15 min were acquired(3 min/scan).The emission data were reconstructed using different techniques.The image quality parameters were evaluated by both phantoms.Variations in the signal-to-noise ratio(SNR)in a 28-mm(10-mm)sphere of phantom II were 37.9%(86.5%)for ordered-subset expectation maximization(OSEM-only),36.8%(81.5%)for point spread function(PSF),32.7%(80.7%)for time of flight(TOF),and 31.5%(77.8%)for OSEM+PSF+TOF,respectively,indicating that OSEM+PSF+TOF reconstruction had the lowest noise levels and lowest coefficient of variation(COV)values.Random and scatter coincidences from outside the FOV induced lower SNR,lower contrast,and higher COV values,indicating image deterioration and significantly impacting smaller sphere sizes.Amongst reconstruction protocols,OSEM+PSF+TOF and OSEM+PSF showed higher contrast values for sphere sizes of 22,28,and 37 mm and higher contrast recovery coefficient values for smaller sphere sizes of 10 and 13 mm. 展开更多
关键词 Positron emission tomography/computed tomography(PET/CT) Random coincidences Scatter coincidences·time of flight(TOF) Point spread function(PSF) Field of view(FOV) Noise equivalent count rate(NECR) Signal-toNoise ratio(SNR)
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不同比对方式下的洲际标准时间复现性能分析
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作者 许龙霞 刘娅 +2 位作者 陈瑞琼 赵志雄 孟令达 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第2期160-167,共8页
中国科学院国家授时中心研制的标准时间复现系统具备支持洲际用户对标准时间频率信号的需求。本文以位于欧洲白俄罗斯明斯克的复现终端为分析对象,分析了共视、全视不同比对方式对复现时频信号性能的影响。对于洲际范围的时间复现,复现... 中国科学院国家授时中心研制的标准时间复现系统具备支持洲际用户对标准时间频率信号的需求。本文以位于欧洲白俄罗斯明斯克的复现终端为分析对象,分析了共视、全视不同比对方式对复现时频信号性能的影响。对于洲际范围的时间复现,复现终端与参考端共同可视卫星数变少。单一卫星导航系统可利用的共视卫星数明显减少,GPS/BDS共视可明显增加可视卫星数量,提高共视时间比对精度,全视比对对两地共同可视卫星数没有要求。分析结果表明,单GPS全视比对就可以达到优于GPS/BDS的共视比对复现效果。受BDS卫星星间偏差的影响,基于单BDS全视比对的复现效果比GPS稍差,GPS/BDS全视比对效果略有改善。复现终端运行在GPS/BDS共视比对融合GPS全视比对模式复现的时频信号的性能最优,可以满足洲际范围内5 ns的时间同步要求,为后续洲际大尺度范围的标准时间复现终端的运行模式提供参考。 展开更多
关键词 共视时间比对 全视时间比对 标准时间复现 GPS BDS
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Real Time Chatter Vibration Control System in High Speed Milling
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作者 Hyeok Kim Mun-Ho Cho +2 位作者 Jun-Yeong Koo Jong-Whan Lee Jeong-Suk Kim 《材料科学与工程(中英文A版)》 2015年第5期221-229,共9页
关键词 振动控制系统 高速铣削加工 实时控制 快速傅里叶变换 切削颤振 刀具寿命 切削条件 表面完整性
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有限视场下的攻击时间和角度多约束制导律 被引量:2
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作者 王江 刘经纬 +1 位作者 崔晓曦 范卫鹏 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第1期18-27,共10页
针对精确打击任务存在导引头视场受限这一过程约束的制导问题,提出了一种考虑视场限制以及攻击角度和时间多种约束的制导律.首先,在以比例导引项实现精确命中的基础上,利用最优控制理论,采用弹目距离加权控制能耗形式的指标函数,设计了... 针对精确打击任务存在导引头视场受限这一过程约束的制导问题,提出了一种考虑视场限制以及攻击角度和时间多种约束的制导律.首先,在以比例导引项实现精确命中的基础上,利用最优控制理论,采用弹目距离加权控制能耗形式的指标函数,设计了攻击角度控制项,并推导了相应的剩余飞行时间解析预测表达式.其次,基于最优误差动力学方法,设计了攻击时间相关的控制项,保证了攻击时间误差的有限时间收敛.同时,针对导引头视场有限的问题,分析了各控制项对前置角收敛性的影响,利用特定的限制函数确保前置角在整个制导过程中始终处于有效视场内,并给出了前置角的有界性及收敛性证明.数学仿真结果验证了所提出制导律对多约束制导问题的有效性. 展开更多
关键词 最优控制 攻击角度控制 攻击时间控制 视场约束 最优误差动力学
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时间传递链路闭合钟差处理方法与性能分析
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作者 陈亮 展昕 +1 位作者 王崇阳 郭晓松 《导航定位学报》 CSCD 北大核心 2024年第3期55-62,共8页
守时实验室和全球卫星导航系统(GNSS)维持的时间基准都通过不同溯源链路溯源至UTC(k),k为实验室代号。目前主流溯源方式包括光纤时间传递、卫星双向时间传递和GNSS共视时间传递。通过对不同溯源链路构造闭环钟差模型,利用间接平差修正... 守时实验室和全球卫星导航系统(GNSS)维持的时间基准都通过不同溯源链路溯源至UTC(k),k为实验室代号。目前主流溯源方式包括光纤时间传递、卫星双向时间传递和GNSS共视时间传递。通过对不同溯源链路构造闭环钟差模型,利用间接平差修正各溯源链路钟差,消除了不同链路中存在在系统差和周期项等误差,提升了时间传递精度。采用5个时频站中8条独立不同溯源链路的钟差实测数据的对算法进行验证,结果表明:由于存在未消除空间误差的影响,卫星双向时间传递和GNSS共视时间传递在长基线条件下都存在明显的周期项,通过对溯源链路的平差修正,消除了溯源钟差不闭合的问题。通过对钟差的二次多项式拟合得到的残差计算,GNSS共视时间传递噪声由0.43ns降低至0.25 ns,卫星双向时间传递噪声0.21 ns降低至0.14 ns,光纤时间传递噪声由0.18 ns降低至0.12 ns。通过提升各溯源链路的时间传递精度,有效地改善了各时间基准的服务能力。 展开更多
关键词 时间基准 时间频率传递 共视 残差 平差
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