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Iterative maximum likelihood time delay and Doppler estimation using stationary signalsJanuary 1989 (has links)
Bruce R. Musicus and Ehud Weinstein. / Includes bibliographical references (p. 155-156). / Supported by the USA AMCCOM and ARDEC. Supported by the U.S. Army Research Office managed by Battelle. DAAL03-86-D-0001 Supported in part by the Advanced Research Projects Agency monitored by ONR. N00014-85-K-0272
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從語言角度考察今本《鄧析子》的成書時代= Dating the extant version of the Deng Xi Zi: a linguistic and the textual exploration吳佩蓉, 17 January 2014 (has links)
《 鄧析子》為先秦名家典籍,《 漢書﹒藝文志》將之列為名家之首。 惟 所錄的仁部名家典籍中, 只得《 尹文子》 、《公孫龍子》 及 《鄧析子》仍流傳於世。然而今本《鄧析子》的成書時代卻有多達六種的說法, 時代更橫跨春秋至唐宋以後, 使到相關研究在缺乏明確的成書時代下,很難得到學者的 認同。前人研究今本《鄧析子》的成書時代,多著眼於二手文獻材料, 或其思想內容等等,鮮有從語言著手。語言是最能反映文本的時代的,故本文嘗試以這種最切身的方法, 研究今本《鄧析子》的成書時代。 本文首先詳細校勘了今本《鄧析子》及《鄧敘錄》的文本,為全文的論述奠下根基。又把《鄧析子》及《鄧敘錄》細分成古本及今本兩個概念, 以清綱目。第二章考釋了今本《鄧敘錄》的內涵和流傳情況,並配合唐宋時代的文獻記載,推斷今本《鄧析子》的成書時代。第三章為本文的主體部份,從新詞新義、舊詞新義及中古語法的角度切人,除考釋這些詞語的配搭外,亦著重其演變的情況、使用的環境,以判定這些詞語出現的時代上下限。其中共發現15個新詞新義的詞語﹔1個舊詞新義的詞語﹔及2個具中古語法特徵的詞語。藉助這些例證,並輔以第二章據舊志及文獻紀錄的推測,得出今本《 鄧析子》的成書時代為西晉末年間。
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Earthquake Focal Mechanism And Stress Tensor Analysisalong The Central Segment Of The North Anatolian FaultKarasozen, Ezgi 01 July 2010 (has links) (PDF)
The North Anatolian Fault (NAF) is one of the world&rsquo / s largest active continental strikeslip
faults, and forms the northern margin of the Anatolian plate. Although its geologic
and geomorphologic features are well defined, crustal deformation and associated
seismicity around central segment of the NAF is relatively less-known. In this study, we
analyzed locations and focal mechanisms of 172 events with magnitude &ge / 3, which are
recorded by 39 broadband seismic stations deployed by the North Anatolian Passive
Seismic Experiment (2005-2008). Distribution of the events shows that the local
seismicity in the area is widely distributed, suggesting a widespread continental
deformation, particularly in the southern block. For the entire data set, P- and S- arrival
times are picked and events are relocated using the HYPOCENTER program. Then,
relocated events which have a good azimuthal coverage with a maximum gap of 120° / and at least 13 P- wave readings are selected and 1-D inversion algorithm, VELEST, is
used to derive the 1-D seismic velocity model of the region. The final model with
updated locations is later put together to the FOCMEC program, to obtain focal
mechanisms solutions. In this step, an iterative scheme is applied by increasing the
number of data errors. To obtain more unique solutions, first motions of P and SH
v
phases are used along with SH/P amplitude ratios. Resultant 109 well-constrained focal
mechanisms later used to perform stress tensor inversion across the region.
Our focal mechanisms suggest a dominant strike-slip deformation along two major fault
sets in the region. In the east, E-W trending splays (Ezinepazari, Almus, and Laç / in
Kizilirmak) show right-lateral strike-slip motion similar to the NAF whereas in the west,
N-S trending faults (Dodurga, Eldivan) show left lateral strike-slip motion. Overall,
stress orientations are found as: maximum principal stress, &sigma / 1, is found to be
subhorizontal striking NW-SE, the intermediate principle stress, &sigma / 2, is vertically
orientated and the minimum principal stress, &sigma / 3, is found to be NE &ndash / SW striking,
consistent with the strike-slip regime of the region.
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An Integrated Seismic Hazard Framework For Liquefaction Triggering Assessment Of Earthfill Dams' / Foundation SoilsUnsal Oral, Sevinc 01 February 2009 (has links) (PDF)
Within the confines of this study, seismic soil liquefaction triggering potential of a dam foundation is assessed within an integrated probabilistic seismic hazard assessment framework. More specifically, the scheme presented hereby directly integrates effective stress-based seismic soil liquefaction triggering assessment with seismic hazard analysis framework, supported by an illustrative case. The proposed methodology successively, i) processes the discrete stages of probabilistic seismic hazard workflow upon seismic source characterization, ii) numerically develops the target elastic acceleration response spectra for typical rock sites, covering all the earthquake scenarios that are re-grouped with respect to earthquake magnitude and distance, iii) matches the strong ground motion records selected from a database with the target response spectra for every defined scenario, and iv) performs 2-D equivalent linear seismic response analyses of a 56 m high earth fill dam founded on 24 m thick alluvial deposits. Results of seismic response analyses are presented in the form of annual probability of excess pore pressure ratios and seismically-induced lateral deformations exceeding various threshold values. For the purpose of assessing the safety of the dam slopes, phi-c reduction based slope stability analyses were also performed representing post-liquefaction conditions. After having integrated this phi-c reduction analyses results into the probabilistic hazard framework, annual probabilities of factor of safety of slopes exceeding various threshold values were estimated. As the concluding remark, probability of liquefaction triggering, induced deformations and factor of safeties are presented for a service life of 100 years. It is believed that the proposed probabilistic seismic performance assessment methodology which incorporates both phi-c reduction based failure probabilities and seismic soil liquefaction-induced deformation potentials, provides dam engineers a robust methodology to rationally quantify the level of confidence with their decisions regarding if costly mitigation of dam foundation soils against seismic soil liquefaction triggering hazard and induced risks is necessary.
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Neotectonics Of The Karamik Graben-afyon- (isparta Angle), Sw TurkeyCicek, Aydin 01 July 2009 (has links) (PDF)
ABSTRACT
NEOTECTONICS OF THE KARAMIK GRABEN-AFYON-(ISPARTA ANGLE), SW
TURKEY
Ç / iç / ek, Aydin
M.Sc., Department of Geological Engineering
Supervisor: Prof. Dr. Ali Koç / yigit
July 2009, 98 pages
The Karamik Graben (KG) is 6-17-km-wide, 29-km-long and NNE-SSWtrending
active depression located within the Isparta Angle of the Southwestern
Turkey extensional neotectonic domain. The KG is bounded by ENE-SSWtrending
Karacaö / ren fault zone to the south, the NNE-SSW-trending Koç / beyli-
Akkonak fault zone to the east, the WNW-ESE-trending AkSehir fault zone to the
north, and the NE-SW to NNE-SSW-trending Devederesi fault zone to the west.
The KG contains two graben infills separated by an angular unconformity:
(1) Middle Miocene-Middle Pliocene deformed infill, and (2) the Upper Pliocenerecent
non-deformed infill. Some geological structures reveal that the older infill
was accumulated under the control of an extensional tectonic regime (phase-I
extension). Analysis of NW-SE-trending folds and some strike-slip faults indicate
that the older infill deformed by a short-term NE-SW-directed compression. This
contractional event is the last record of the paleotectonic period. Some geological and geophysical evidence indicate that the younger infill has been deposited under the control of an extensional tectonic regime (phase-II extension). Analysis of some slickensides implies that the current tectonic regime
is being characterized by a multi-directional extension in predominantly N-S, E-W and NW-SE directions. This multi-directional extension dominates the Plio- Quaternary neotectonic period initiated Late Pliocene.
Total throw amounts accumulated along the margin boundary faults imply that subsidence rates are ~0.15 mm/yr and ~0.21 mm/yr since Late Pliocene.
Some of the northern margin-boundary faults of the KG reactivated during the neotectonic period as evidenced by 2002.02.02 Mw = 6.5 Ç / ay earthquake.
However, the rest of these faults are still active and they keep their nature of seismic gap.
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Analysis Of Seismic Behavior Of Underground Structures: A Case Study On Bolu TunnelsErtugrul, Niyazi 01 December 2010 (has links) (PDF)
In today&rsquo / s world, buried structures are used for a variety of purposes in many areas such as transportation, underground depot areas, metro stations and water transportation. The serviceability of these structures is crucial in many cases following an earthquake / that is, the earthquake should not impose such damage leading to the loss of serviceability of the structure. The seismic design methodology utilized for these structures differs in many ways from the above ground structures. The most commonly utilized approach in dynamic analysis of underground structures is to neglect the inertial forces of the substructures since these forces are relatively insignificant contrary to the case of surface structures. In seismic design of these underground structures, different approaches are utilized like free-field deformation approach and soil-structure interaction approach.
Within the confines of this thesis, seismic response of highway tunnels is considered through a case study on Bolu Tunnels, which are well documented and subjected to Dü / zce earthquake. In the analyses, the seismic response of a section of the Bolu tunnels is examined with 2-D finite element models and results are compared with the recorded data to evaluate the capability of the available analysis methods. In general, the results of analyses did not show any distinct difference from the recorded data regarding the seismic performance of the analyzed section and that the liner capacities were sufficient, which is consistent with the post earthquake condition of the Bolu Tunnels.
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Probabilistic Seismic Hazard Assessment For EskisehirGenc, Gence 01 September 2004 (has links) (PDF)
The purpose of this study is to develop probabilistic hazard maps for EskiSehir including &lsquo / Peak Ground Acceleration&rsquo / values for 10% probability of exceedance in 50-year and 100-year periods at different site classes.
A seismotectonic map has been prepared in the Geographical Information Systems environment by compiling instrumental seismicity and neotectonic data for the study area.
The seismic sources have been defined spatially in six areal zones, characterized by a commonly used recurrence law and a maximum magnitude value.
Four attenuation relationships have been selected being one of them totaly developed from the strong-motion records of Turkey.
After the implementation of a seismic hazard model by using SEISRISK software, the probabilistic seismic hazard curves and maps were developed based on the selected attenuation relationships, at &lsquo / rock&rsquo / and &lsquo / soil&rsquo / sites, with a probability of exceedance of 10% in 50-year and 100-year periods. At rock sites the highest levels of hazard were calculated based on the predictive relationship of Abrahamson and Silva (1996), whereas the lowest ones based on the one of Boore et al. (1996). On the other hand the highest hazard levels were determined at soil sites based on the attenuation relationship of Ambraseys et al. (1996), whereas the lowest ones based on the one of Boore et al. (1997).
For EskiSehir, the peak ground acceleration values calculated based on attenuation relationship by Boore et al. (1997) were found to be applicable for 10% probability of exceedance in 50 and 100 years, taking into consideration the fact that a considerable portion of the city is founded over alluviums.
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Estimation Of Dynamic Soil Properties And Soil Amplification Ratios With Alternative TechniquesSisman, Fatma Nurten 01 January 2013 (has links) (PDF)
Earthquakes are among the most destructive natural disasters affecting urban populations. Structural damage caused by the earthquakes varies depending not only on the seismic source and propagation properties but also on the soil properties. The amplitude and frequency content of seismic shear waves reaching the earth&rsquo / s surface is dependent on local soil conditions. It is well known that the soft sediments on top of hard bedrock can greatly amplify the ground motion and cause severe structural damage. When the fundamental period of the soil is close to the fundamental period of a structure, structural damage increases significantly. Estimation of the fundamental periods, amplification factors and types of soils is critical in terms of reduction of loss and casualties. For the reasons stated, estimation of dynamic behavior of soils has become one of the major topics of earthquake engineering. Studies for determining dynamic properties of soils depend fundamentally on the estimation of the S-wave velocity profiles, amplification factors and ground response.
In this study first, the Multi-Mode Spatial Autocorrelation (MMSPAC) method is used to estimate the S-wave velocity profiles at the sites of interest. This method is different than the other ones in the sense that it works for the higher modes as well as the fundamental mode. In the second part, Horizontal to Vertical Spectral Ratio (HVSR) method will be used on both microtremor and ground motion data. Finally, the amplification factors from alternative methods are compared with each other. Consistent results are obtained in terms of both fundamental frequencies and amplification factors.
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Evaluation Of Alluvial Deposits In Gemlik Basin In Terms Of Earthquake OdesAvsar, Ulas 01 May 2006 (has links) (PDF)
Gemlik County is located in the Marmara Region (NW Turkey), which has been affected by destructive earthquakes sourced from North Anatolian Fault System throughout its history. The bulk of the settlement rests on alluvial deposits of the Gemlik pull-apart basin. So, it is vital to investigate the foundation soils in this basin and the response of them to earthquakes. Many earthquake codes were established by the authorities in different countries of the world to estimate the possible ground shaking and seismic loads which may act on buildings. In this study, Turkish Earthquake Code (TEC-1998) and Eurocode-8 (EN-1998) have been utilized. The analyses showed that EN-1998 results in more conservative estimates relative to TEC-1998, in terms of spectral ordinates. The source of difference between TEC-1998 and EN-1998 has been investigated and three possible reasons have been identified. The variation is probably due to the different seismic characteristics of Turkey and Europe, different soil amplification levels defined by the codes, and different soil classification procedures of the codes.
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Probabilistic Seismic Hazard Assessment For Earthquake Induced LandslidesBalal, Onur 01 January 2013 (has links) (PDF)
Earthquake-induced slope instability is one of the major sources of earthquake hazards in near fault regions. Simplified tools, such as Newmark&rsquo / s Sliding Block (NSB) Analysis are widely used to represent the stability of a slope under earthquake shaking. The outcome of this analogy is the slope displacement where larger displacement values indicate higher seismic slope instability risk. Recent studies in the literature propose empirical models between the slope displacement and single or multiple ground motion intensity measures such as peak ground acceleration or Arias intensity. These correlations are based on the analysis of large datasets from global ground motion recording database (PEER NGA-W1 Database). Ground motions from earthquakes occurred in Turkey are poorly represented in NGA-W1 database since corrected and processed data from Turkey was not available until recently. The objective of this study is to evaluate the compatibility of available NSB displacement prediction models for the Probabilistic Seismic Hazard Assessment (PSHA) applications in Turkey using a comprehensive dataset of ground motions recorded during earthquakes occurred in Turkey. Then the application of selected NSB displacement prediction model in a vector-valued PSHA framework is demonstrated with the explanations of seismic source characterization, ground motion prediction models and ground motion intensity measure correlation coefficients. The results of the study is presented in terms of hazard curves and a comparison is made with a case history in Asarsuyu Region where seismically induced landslides (Bakacak Landslides) had taken place during 1999 Dü / zce Earthquake.
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