An algorithm for detecting and estimating cycle slips in single-frequency GPS   总被引：1，自引：0，他引：1  

Jia Pei-zhang  Wu Lian-da 《Chinese Astronomy and Astrophysics》2001,25(4):1089-521

An algorithm for detecting outliers and cycle slips in single-frequency GPS using a 3rd order polynomial model of the Kalman filter and for estimating the ambiguity by using optimal wavelet is presented in this paper. It is applicable to the carrier phase measurement with sample rate of one per second. The results of calculation with the GPS data aboard satellite Topex on 1995 June 22 show that the algorithm is so efficient that it can accurately estimate the ambiguity even for signals interrupted by a few seconds.  相似文献   

Morphological characters of the two-ribbon flare of 1981 May 13 and their explanation     

Zu-yan Zhu  Hong-ao Wu  Tian-jun Cao 《Chinese Astronomy and Astrophysics》1985,9(2):119-123

We give a summary of the morphology of the two-ribbon flare of 1981 May 13. One striking feature is that the Ha flare began at about 0338' UT and the double-ribbon structure was formed about 0346, $\text{before}$ the impulsive phase of the radio 3 cm burst at 04 11 UT. The 3 cm radio burst flux beginning at 03 33 UT showed only slow, stepwise increases lasting half an hour until the impulsive phase and this type of increase is usually regarded to be a typical thermal process. Each step in the radio flux corresponded to a variation in the Ha flare, showing that the radio and Hα emissions during this period came from the same thermal source. In this paper, we explain this behaviour in terms of Hyder's model: we think that the magnetic trough supporting the solar prominence rose for some reason, causing the prominence matter (the dark filaments) to fall along the magnetic lines and to hit the chromosphere and trigger off the flare. We give rough estimates of the energy density, the height of prominence and the infall matter at the different radio increments. We also give a qualitative explanation for the appearances of the single-peak structure in the radio burst at 0411 and the covering of the sunspot shortly after at 04 13 and propose several possible mechanisms.  相似文献   

Systematic uncertainties in the analysis of star cluster parameters based on broad-band imaging observations     

R. de Grijs  P. Anders  H. J. G. L. M. Lamers  N. Bastian  U. Fritze-v. Alvensleben  G. Parmentier †  M. E. Sharina  S. Yi 《Monthly notices of the Royal Astronomical Society》2005,359(3):874-894

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陕西秦巴山区农业自然资源开发利用     

刘胤汉  陆立新 《山地学报》1990,(1)

农业自然资源据其在农业利用过程中的地位可分为两类:一类是生成农业自然资源的环境,另一类为可资直接利用的自然生成物(即狭义的农业自然资源)。陕西秦巴山区自然环境的主要特点是:复合山体高峻庞大,地跨暖温带和北亚热带,垂直分异明显。区内有:森林、草场、野生生物、林特产与农作物等多种农业自然资源。据此,提出了本区农业自然资源的开发利用途径。  相似文献   

现代天文选址中的视宁度（Ⅱ）     

仇朴章  刘忠 《天文学进展》1996,14(3):175-180

在文献」１「４ 基础上，根据近年文选址实践中提出的问题，先进一步讨论了大气相干直径和时间的的物理和意义，然后强调了自由大气湍流的天文成像效应及选址中进行研究和测量的重要性。最后对差分像运动方法测量视宁度的定标和系统误差等问题作了分析。  相似文献   

The Optical Gravitational Lensing Experiment: catalogue of stellar proper motions in the OGLE-II Galactic bulge fields     

T. Sumi  X. Wu  A. Udalski  M. Szyma&#;ski  M. Kubiak  G. Pietrzy&#;ski  I. Soszy&#;ski  P. Wo&#;niak  K. &#;ebru&#;  O. Szewczyk  &#;. Wyrzykowski 《Monthly notices of the Royal Astronomical Society》2004,348(4):1439-1450

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Statistical analysis of surface hydrography and circulation variations in northern South China Sea     

吴玲娟  崔茂常 《中国海洋湖沼学报》2005,23(4):383-392

1 INTRODUCTIONThe South China Sea (SCS) is a semi-enclosedmarginal sea in western North Pacific Ocean withvery complex topography and is the important pas-sage connecting the Pacific and Indian Oceans. Ithas great impact to the global climate and a greatinterest of many oceanography researchers. Twodominant surface hydrographic and circulation fea-tures in the northern SCS are a strong fresh waterexpansion and a warm and high-salinity seawaterintrusion such as the SCS Diluted Water…  相似文献   

X-shaped radio galaxies as observational evidence for the interaction of supermassive binary black holes and accretion disc at parsec scale     

F. K. Liu 《Monthly notices of the Royal Astronomical Society》2004,347(4):1357-1369

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元岭金矿蚀变破碎带特征及其找矿意义     

刘红樱  周顺之  胡受奚  王群昌 《河南国土资源》1996,(2)

根据对元岭金矿三条蚀变破碎带一般地质特征、微量元素特征的对比研究，并借鉴邻近矿区蚀变破碎带的矿化特征，本文阐明了元岭蚀变破碎带矿化的有利构造部位，总结了蚀变破碎带特征与矿化强度之间的关系，指出蚀变破碎带的矿化蚀变元素为中低温组合，矿化蚀变愈强则参与元素的种类愈多、数量愈大。围岩性质对矿化蚀变有一定影响，围岩中的易迁移亲铜元素和亲硫铁族无素对矿化有利。据此，为进一步成矿预测、评价蚀变破碎带的含矿性提供依据。  相似文献   

彭州市立体农业气候资源的研究(二)热量资源分析   总被引：2，自引：0，他引：2  

周定文  胡毅 《成都信息工程学院学报》2001,16(3):169-173

利用彭州市境内市气象站，新兴，白果坪的日平均气温资料，进行热量资源分析。结果表明，彭州市7－8月为最热月，多年平均温度低于24．9℃，12－2月为最冷月，多年平均温度高于1．7℃。大多数年全年稳定通过0℃，可一年四季进行农业耕作，有利于作物越冬和多年生作物的种植，生长期长，积温丰富。界限温度的初，终日期及持续日数变化较大，积温际变化显著，热量资源随海拔高度增加而减少，各界限温度的初日推迟，终日提前，持续日数和积温减少，温度强度也降低，形成显著的立体农业气候。  相似文献