Combination procedure for length-of-day time series according to the noise frequency behavior

 Length-of-day (LOD) estimates from seven Global Positioning System (GPS) and three satellite laser ranging (SLR) analysis centers were combined into an even-spaced time series for a 27-month period (1996–1998). This time series was compared to the multi-technique Earth-orientation-parameter (EOP) combined solution (C04) derived at the Central Bureau of the International Earth Rotation Service (IERS/CB). Due to inhomogeneities in the different series derived from the various techniques (time, length, quality, and spatial resolution), the concept of a combined solution is justified. The noise behavior in LOD for different techniques varies with frequency; the data series were divided into frequency windows after removing both biases and trends. Different weight factors were assigned in each window, discriminating by technique, and produced one-technique combined solutions. Finally, these one-technique combined solutions were combined to obtain the final multi-technique solution. The LOD combined time series obtained by the present method based on the frequency windows combined series (FWCS) is very close to the IERS C04 solution. It could be useful to generate a new LOD reference time series to be used in the study of high-frequency variations of Earth rotation. Received: 28 March 2000 / Accepted: 15 February 2001     

地震场源应变前兆的区别及其在地震预报中的应用

本文以组合模式基础，用三维有限元方法计算了两个模型，主要研究结论是：（１）在发生大地震前，调整单元首先破裂，其应变随时间变化曲线呈准“λ”型；（２）在调整单元破裂后，积累单元破裂，其应变随时间变化曲线呈“λ”型；（３）在断层垂直方向上应变衰减很快，而沿断层走向方向上衰减很慢；（４）场区各单元的情况很复杂，其应变随时间变化的曲线呈非“λ”型。最后本文列举了一些有关“λ”型的震例，并利用结论（１）解释了几种前兆现象。     

Automated Ion-pair extraction and Ion-pair chromatography — a versatile method in water analysis for the determination of highly polar micropollutants

An automated HPLC method is presented which combines on-line ion-pair extraction on small exchangeable RP-C18 precolumns (RP-IPE) with ion-pair chromatography (RP-IPC). Weakly acidic herbicides — carboxylic acids, phenols, and the N-H acidic bentazone — and strong acids, e.g. aromatic sulfonic acids, can be determined simultaneously. Performance data are given. The tetrabutylammonium ion pairs of all investigated compounds are readily transferred from the RP-C18 precolumn to the analytical column by a phosphate buffer/methanol gradient. This is also true for the chlorinated phenoxy acids which, in earlier off-line extraction experiments, could not be desorbed from the RP-C18 material by the lower polar acetone. The RP-IPC is carried out at neutral pH where weakly acidic compounds appear in their stronger UV absorbing dissociated form. Compared to conventional reversed phase chromatography using an acidified eluent, the sensitivity of UV detection is markedly enhanced, especially for the phenol herbicides and bentazone. In addition, phenols can be detected more selectively because they show a second intense absorption band in the wavelength range between 280 nm and 290 nm, where there are only little interferences with the matrix. Due to miniaturization and automation, the online combination IPE/IPC allows a large sample throughput at a lower consumption of solid phase material and organic solvents. Time consuming manual steps are totally missing. The IPE/IPC technique is well suited as a screening method for fate studies of polar micropollutants, e. g. for monitoring the efficiency of different water treatment technologies. An example for balancing an activated carbon filter is presented.     

密度分层组合合成技术及影象地质解译

密度分层组合成技术是通过对遥感图象密度层次的分折,以突出影象的结构信息为主的一种光孚图象处理方法。根据不同密度层次的多波段遥感图象具有不同类别结构的“信息丰度”的原理,通过对分层片的组合处理,比较成功地对影象信息进行增强和提取,从而获得较好的地质解译效果。实践表明,它不仅对构造解译是有效的,而且对地层、岩性解译也是可行的。在矿床、矿田构造解译力面,它可以获得一些以前没有被认识的信息。本文是基于对我国某铀矿田的卫片进行密度分层处理和解译,提出了矿田受菱形断裂构造块体控制的看法。它对认识铀矿田的构造特点,指导找矿是有一定意义的。     

应用遥感信息复合方法的森林分类和动态监测研究

在森林资源清查和动态监测中，一般要求能识别树种、在树种复杂时也要求识别到树种组。成图时要求可直接使用几何精度高、类型边界清晰的中比例尺如１：２．５万的影像图。为了满足生产的需要，我们进行了遥感信息复合、遥感与非遥感信息复合及复合方法等实用技术应用的研究。实验中应用了ＭＳＳ与ＴＭ卫星图像、ＴＭ不同时相的图像、ＴＭ与Ｓｐｏｔ的复合，及复合前后信息特征变化的定量分析等研究。从而为最优波段组合、特征信息提取方法提供了基础。在动态分析中主要进行了采伐迹地、林墙、迹地更新等方面的测定，并对测定精度进行了评估。     

Effective Removal of Microorganisms and Biostimulants of Wastewater by the Application of Various Electrolytes

A variety of electrolytes FeCl₃, CaCl₂, CuSO₄, Al₂(SO₄)₃, and LaCl₃ was investigated for their efficiency in removing biostimulants (phosphorous and nitrogen) to improve the water quality. Results show that the removal of PO₄^3– was achieved below the detection limit (BDL) by two electrolytes, CuSO₄ and Al₂(SO₄)₃, and up to 1.0 ± 0.0 mg/L by LaCl₃ from a value of 15.0 mg/L, of the concentration of PO₄^3– in amended water. The turbidity was found to be removed significantly by FeCl₃, CuSO₄, and Al₂(SO₄)₃ by about 5.8 ± 2.6, 9.7 ± 1.0, and 5.4 ± 1.1 nephalometric turbidity unit (NTU), respectively. The removal of the members of Enterobacteriaceae viz., Escherichia coli, Enterobacter spp. Pseudomonas fluorescence, and Pseudomonas spp. was found almost in all the chemical precipitants but their removal was more significant in the water samples treated with CuSO₄, Al₂(SO₄)₃, and LaCl₃. To achieve a complete removal and to sustain the after effects of precipitation, such as recurrence of algal growth, the combination of CuSO₄ and Al₂(SO₄)₃ was investigated. Reduction in the turbidity from 30.83 to <2 NTU, phosphate ion from a value of 1.28 mg/L to BDL and ammonia ion from a value of 44.71 to 36.48 mg/L of natural pond water were observed after the treatment with CuSO₄ and Al₂(SO₄)₃ in combination.     

统计-动力相结合的相似误差订正法

根据大气相似性原理,提出了利用历史资料的相似信息估计模式误差的反问题,并发展了一种相似误差订正(ACE)方法。该方法将统计和动力两种方法有机结合,在不改变现有数值预报模式的前提下,既充分利用了动力学发展的成就,又能够有效提取大量历史资料中的相似信息,达到减小模式误差、改进当前预报的目的。而且,ACE方法能够针对当前预报的特殊性来区分所利用过去资料的特殊性,提取历史相似信息间接求解反问题。定性分析表明,ACE方法与以往相似-动力模式原理是等价的,但无需重新建立复杂的相似离差预报模式,更具可行性和业务应用前景。在理想化的极限情形下,当数值模式或历史相似完全准确时,ACE方法的预报结果将分别蜕变为动力或统计学方法的预报结果。     

数据仓库基础上的辅助决策应饪——指挥监测中心桌面系统简介

指挥监测中心桌面系统是建立在数据仓库基础上,以Business Objects XI作为项目开发运行平台,专门为领导决策服务的定制系统,实现预警、监督、查询等功能,重点是实现主要关注指标的实时监测。     

地震场源应变前兆的区别及其三维有限元模拟

以组合模式为基础,用三维有限元方法计算了两个模型,主要研究结论是:①在大地震发生前,调整单元首先破裂,其应变随时间变化曲线呈准"λ"型;②在调整单元破裂后,积累单元破裂,其应变随时间变化曲线呈"λ"型;③在断层垂直方向上应变衰减很快,而沿断层走向方向衰减很慢;④场区各单元的情况很复杂,其应变随时间变化的曲线呈非"λ"型。并用数值分析方法证实了组合模式的正确性,还用结论(1)解释了几种前兆现象。