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351.
以整个中国海为研究区域,把开边界取在TOPEX/POSEIDON(T/P)高度计资料数据点,利用趋近插值法将高度计资料同化到二维非线性潮汐数值模式中,反演了中国近海M2分潮的分布.计算结果与60个验潮站资料比较,符合良好振幅平均绝对偏差为6.7cm,相角偏差为5.5°,均方根偏差为12.6cm.根据计算结果给出东中国海和南海M2分潮的同潮图,与相关文献比较,符合良好.研究结果表明,以本方法利用T/P资料来反演中国海潮汐是可行的. 相似文献
352.
Accurate decomposition of Electron Spin Resonance (ESR) spectrum is a crucial task to extract compound signal intensities of enamel fragments at different irradiation time, in particular for dose recovery accuracy. While it can be achieved manually, the task is laborious and repetitive. In this paper, we present a new freely available program “ESRfrag” that allows the alignment, merging, and computation of complex angular ESR spectra. This program is an open access web-based code, designed to specifically alleviate the daunting task of working with large amounts of ESR spectra for enamel fragment dating. ESRfrag provides an increased reliability and precision on the results compared to manual calculation by removing operators bias. The program can be freely access through the Geoarchaeology and Archaeometry Research Group website (https://www.garg.org.au/projects). 相似文献
353.
A deep ROSAT PSPC image centred on the Orion Trapezium has been reduceda second time using an improved version of the PSF to fit the data. The outer rim of the field of view was also included. The new catalogue contains 316 X‐ray sources which are easily identified with pre‐main sequence stars of the Ori OB1 Ic and Id association. All 316 sources were tested for variability. No variations were found inside the single exposures of about 45 minutes length each. Between the 4 exposures spaced over 5 days about 1/3 of the sources show signs of activities of various forms. As above 25% of these have somewhat regular lights curves (monotonically rising or falling or hill‐shaped) we infer that at least some outbursts with time scales longer than a day are present and that past searches for X‐ray flares of pre‐main sequence stars were biased towards shorter time scales. 相似文献