Automatic classification of dome instabilities based on Doppler radar measurements at Merapi volcano, Indonesia: Part II     

M. Vöge  M. Hort  R. Seyfried  A. Ratdomopurbo 《Geophysical Journal International》2008,172(3):1207-1218

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Geodetic inversion for space–time distribution of fault slip with time-varying smoothing regularization     

Jun'ichi Fukuda  Shin'ichi Miyazaki  Tomoyuki Higuchi  Teruyuki Kato 《Geophysical Journal International》2008,173(1):25-48

We have developed a new geodetic inversion method for space–time distribution of fault slip velocity with time-varying smoothing regularization in order to reconstruct accurate time histories of aseismic fault slip transients. We introduce a temporal smoothing regularization on slip and slip velocity through a Bayesian state space approach in which the strength of regularization (temporal smoothness of slip velocity) is controlled by a hyperparameter. The time-varying smoothing regularization is realized by treating the hyperparameter as a time-dependent stochastic variable and adopting a hierarchical Bayesian state space model, in which a prior distribution on the hyperparameter is introduced in addition to a conventional Bayesian state space model. We have tested this inversion method on two synthetic data sets generated by simulated aseismic slip transients. Results show that our method reproduces well both rapid changes of slip velocity and steady-state velocity without significant oversmoothing and undersmoothing, which has been hard to overcome by the conventional Bayesian approach with time-independent smoothing regularization. Application of this method to transient deformation in 2002 caused by a silent earthquake off the Boso peninsula, Japan, also shows similar advantages of this method over the conventional approach.  相似文献   

Seismicity rate and wave-velocity variations as consequences of rainfall: the case of the catastrophic storm of September 2002 in the Nîmes Fault region (Gard, France)   总被引：1，自引：0，他引：1  

Alexis Rigo  Nicole Béthoux  Frédéric Masson  Jean-François Ritz 《Geophysical Journal International》2008,173(2):473-482

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Constraints on surface deformation in the Seattle, WA, urban corridor from satellite radar interferometry time-series analysis     

Noah J. Finnegan  Mathew E. Pritchard  Rowena B. Lohman  Paul R. Lundgren 《Geophysical Journal International》2008,174(1):29-41

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Low detection capability of global earthquakes after the occurrence of large earthquakes: investigation of the Harvard CMT catalogue   总被引：4，自引：0，他引：4  

Takaki Iwata 《Geophysical Journal International》2008,174(3):849-856

We investigated the detection capability of global earthquakes immediately after the occurrence of a large earthquake. We stacked global earthquake sequences after occurrences of large earthquakes obtained from the Harvard centroid-moment tensor catalogue, and applied a statistical model that represents an observed magnitude–frequency distribution of earthquakes to the stacked sequence. The temporal variation in model parameters, which corresponds to the detection capability of earthquakes, was estimated using a Bayesian approach. We found that the detection capability of global earthquakes is lower than normal for several hours after the occurrence of large earthquakes; for instance, the duration of lowered detection capability of global earthquakes after the occurrence of an earthquake with a magnitude of seven or larger is estimated to be approximately 12 hr.  相似文献   

基于Nevanlinna-Pick插值的时滞系统鲁棒控制器设计     

王常虹  刘斌  张玉鹏  宋启闻  曲国瑞  孙巍 《东北石油大学学报》2012,36(4):90-94,10

针对时滞系统,提出一种基于Nevanlinna-Pick插值的鲁棒控制器设计方法.它首先通过互质分解得到控制器和灵敏度函数的参数化形式,将控制器的设计转化为灵敏度函数成型;然后利用同伦法求解具有阶次约束的Nevanlin-na-Pick插值问题,从而求得控制器和灵敏度函数.仿真实验结果表明,闭环系统的灵敏度函数由被控对象的非最小相位零点和不稳定极点决定.  相似文献   

连线干涉系统测量共位双星宽带信号处理与分析     

陈明  刘庆会  唐歌实  陈略  李黎  邵华  赵融冰  戴志强 《中国科学院上海天文台年刊》2011,(0)

随着人类空间活动的急剧增加,同步轨道资源已变得十分稀缺。为此人们采用了多星共位技术,来充分挖掘同步轨道资源。多星共位中,由于卫星存在位置漂移的情况,安全问题成为维护卫星正常工作必须考虑的问题之一。考虑到同步卫星的轨道特性,常采用三程测距的方式对卫星进行测轨,而且需要较长时间的测轨弧段。连线干涉测量可以获得高精度的差分相位时延,这对卫星在垂直视线方向上构成了很强的约束。给出了连线干涉测量系统设计及测量数据处理方法,并对测量中的关键技术与设备特性、测量数据精度进行了初步分析。  相似文献   

前陆盆地陆源沉积序列的特征与成因机制   总被引：2，自引：0，他引：2  

吕红华  周祖翼 《地球科学进展》2010,25(7):706-714

前陆盆地接受的来自毗邻造山带的陆源碎屑沉积是盆山耦合关系研究的主要对象之一.这套沉积通常具有以下3个方面的特征:①在地层剖面中,前陆盆地陆源沉积序列呈向上变粗的趋势,其成因有多种可能,包括源区构造隆升、侵蚀卸栽导致的盆地基底均衡回弹、气候变化、岩性变化等;②构造抬升导致的粗粒相沉积事件与构造事件之间存在时滞,其大小取决于源区基岩剥露速率、侵蚀与搬运条件、沉积区距造山带构造变形前缘之间的距离等因素;③粗粒相沉积在前陆盆地内的分布具有穿时性.重视这些方面的研究,有助于得出有关前陆盆地及毗邻造山带演化的合理结论.  相似文献   

大型滑坡发生的时间分布与固体潮的关系     

李松龄  陈征宙 《工程地质学报》2010,18(6):873-879

为研究大型滑坡在发生时间呈现的规律,本文对我国近年来发生的大型滑坡在时间分布和诱导因素上进行了统计。从统计结果可以看出,自然边坡往往在一定的诱导因素下发生失稳破坏,而大型滑坡的失稳破坏在时间分布上则表现出望日或者朔日前后易于发生,并且滑坡在一天中发生的具体时刻则呈现出正态分布的特点。因此,根据固体潮的理论,以及固体潮在一天之中引潮力的变化与滑坡发生时刻的对应关系,本文认为固体潮是诱导大型边坡失稳的因素之一。同时由于组成边坡物质的蠕变特性不同,造成了大型滑坡的发生往往有超前或滞后现象,以上结果为滑坡的预报或预防工作提供了一定的理论支持。  相似文献   

铅物相分析选择性溶剂、浓度及浸取时间探讨   总被引：1，自引：0，他引：1  

朱松  张丽微  韦克桥  余虹 《云南地质》2010,29(2):210-214

个旧铅矿石以铅钒、白铅矿、砷铅矿、方铅矿、铅铁钒为主要赋存状态。试验探讨浸取时间、选择性溶剂、及其浓度对各赋存状态下铅的溶解情况,制定适合个旧地区铅矿石的物相分析方法,取得满意效果。  相似文献