scholarly journals Bayesian Inversion of Wrapped Satellite Interferometric Phase to Estimate Fault and Volcano Surface Ground Deformation Models

2020 ◽  
Author(s):  
Yu Jiang ◽  
Pablo González
Keyword(s):  
Bayesian Approach ◽  
Ground Deformation ◽  
Source Parameters ◽  
Source Model ◽  
Phase Unwrapping ◽  
Point Of View ◽  
Model Parameters ◽  
Novel Approach ◽  
Ill Posed ◽  
The Impact

<p>Phase unwrapping is the process of recovering the absolute phase from unambiguous wrapped phase values that are measured modulo 2pi rad. From a mathematical point of view, phase unwrapping is an inverse problem, however, it is ill-posed and notoriously difficult to solve in the presence of noise. Meanwhile, phase unwrapping errors severely impact the estimation of earthquake and volcano source parameters using interferometric observations, therefore avoiding phase unwrapping completely is desirable. </p><p>A potential solution to avoid the unwrapping error issue completely, is to carry out a geophysical inversion directly on the wrapped phase observations. To overcome the need for phase unwrapping, we propose a novel approach that we can invert directly the interferometric wrapped phase, circumventing the ill-posed phase unwrapping processing step. This approach includes (1) a downsampling algorithm, (2) a method to estimate the covariance function of the wrapped phase, (3) an appropriate misfit function between the observed and the simulated wrapped phase. We also assess the uncertainties of source parameters within a Bayesian approach, and finally we test the robustness of the inversion methodology in multiple simulations including variable decorrelation and atmospheric noise simulations.</p><p>We demonstrate the proposed methodology on synthetic cases with variable noise and one real earthquake case. We show that the method is robust in challenging noise scenarios. We also show an improvement with the Bayesian approach in performance with respect to similar previous methods, resulting in avoiding any influence of seed starting models, and escaping local minima. We study the impact of a small percentage of incorrectly unwrapped phase observations in current state-of-the-art methods, and show that the presence of a small fraction of unwrapping errors affect strongly the estimation process. We conclude that in the cases where phase unwrapping is difficult or even impossible, the proposed inversion methodology with wrapped phase will provide an alternative approach to assess earthquake and volcano source model parameters.</p>

scholarly journals Source Model of the 2014 Mw 6.9 Yutian Earthquake at the Southwestern End of the Altyn Tagh Fault in Tibet Estimated from Satellite Images

2020 ◽  
Vol 91 (6) ◽  
pp. 3161-3170
Author(s):  
Xing Li ◽  
Wenbin Xu ◽  
Sigurjón Jónsson ◽  
Yann Klinger ◽  
Guohong Zhang
Keyword(s):  
Ground Deformation ◽  
Source Parameters ◽  
Source Model ◽  
Coseismic Slip ◽  
Remote Sensing Technology ◽  
Sensing Technology ◽  
Altyn Tagh ◽  
Coulomb Failure Stress Change ◽  
Coulomb Failure ◽  
Source Geometry

Abstract Multiple fault segments ruptured during the 2014 Yutian earthquake, but the detailed source parameters and the mechanism of rupture complexity remain poorly understood. Here, we use high-resolution TanDEM-X satellite data and Satellite Pour l’Observation de la Terre-6/7 images to map the coseismic ground deformation field of the event. We find that the majority of coseismic slip occurred in the upper 10 km with the maximum left-lateral fault slip of ∼2.5  m at ∼6  km depth. The fault ruptured across a large 4.5 km extensional stepover from one left-lateral fault segment to another, with some right-lateral relay faulting in between. We find that the earthquake was followed by shallow afterslip concentrating at the southwestern end of coseismic rupture, in an area of many aftershocks and positive Coulomb failure stress change. Our findings demonstrate the power of satellite remote sensing technology in constraining source geometry and slip model of complex earthquakes when ground measurements are limited.

scholarly journals Heated Topics in Thermochronology and Paths towards Resolution

Geosciences ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 375 ◽  
Author(s):  
Matthew Fox ◽  
Andrew Carter
Keyword(s):  
Approximate Model ◽  
Future Research ◽  
Model Parameters ◽  
Suitable Model ◽  
Temperature Dependent ◽  
Cooling History ◽  
Combine Data ◽  
Exhumation Rate ◽  
Ill Posed ◽  
The Impact

Thermochronometry is widely used to track exhumation, the motion of rock towards Earth’s surface, and to gain fresh insights into geodynamic and geomorphic processes. Applications require models to reconstruct a rock’s cooling history as it is exhumed from higher temperatures at depth within the crust to cooler shallower levels and eventually Earth’s surface. Thermochronometric models are dependent on the predictable accumulation and the temperature-dependent loss of radiogenic daughter products measured in the laboratory. However, there are many geologically reasonable scenarios that will yield very similar thermochronometric ages. This similarity hinders finding the actual scenario, so instead an approximate model is sought. Finding suitable model parameters is a potentially ill-posed inverse problem that requires making decisions about how best to extract information from the data and how to combine data to leverage redundant information and reduce the impact of data noise. Often these decisions lead to differences in conclusions of studies and such discrepancies have led to heated debates. Here, we discuss debates centred on the use of a variety of modelling approaches and potential sources of biases that lead to differences in the predicted exhumation rate. We also provide some suggestions about future research paths that will help resolve these debates.

scholarly journals The Impact of KLT Coder on the Image Distortion in Astronomy

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Petr Pata
Keyword(s):  
Image Data ◽  
Image Distortion ◽  
Point Of View ◽  
The Novel ◽  
Gaussian Probability Density Function ◽  
Novel Approach ◽  
Spread Function ◽  
Karhunen Loeve Transform ◽  
Astronomical Image Processing ◽  
The Impact

Presented paper is devoted to the application of Karhunen-Loève transform (KLT) for compression and to study of KLT impact on the image distortion in astronomy. This transform is an optimal fit for images with Gaussian probability density function in order to minimize the root mean square error (RMSE). The main part of the encoder is proposed in relation to statistical image properties. Selected astronomical image processing algorithms are used for the encoder testing. The astrometry and point spread function distortion are selected as the most important criteria. The results are compared with JPEG2000 standard. The KLT encoder provides better results from the RMSE point of view. These results are promising and show the novel approach to the design of lossy image compression algorithms and also suitability for algorithms of image data structuring for retrieving, transfer, and distribution.

scholarly journals Using the Framework Method for the Analysis of Qualitative Dyadic Data in Health Research

2021 ◽  
pp. 104973232110115
Author(s):  
Nicole Collaço ◽  
Richard Wagland ◽  
Obrey Alexis ◽  
Anna Gavin ◽  
Adam Glaser ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Health Care ◽  
Health Care Professionals ◽  
Qualitative Methodology ◽  
Point Of View ◽  
Dyadic Analysis ◽  
Dyadic Data ◽  
Novel Approach ◽  
Younger Men ◽  
The Impact

There are an increasing number of qualitative studies which focus on the dyad (couples, families, caregivers–patients, health care professionals–patients). However, there is limited literature regarding qualitative methodology for dyadic analysis when members of the couple have been interviewed separately. The aim of this article is to share the knowledge we gained from undertaking a novel approach to dyadic analysis. We used an adapted version of the Framework method on data gathered in a study exploring the impact of prostate cancer on younger men and their partners. In this article, we examine and reflect on the challenges of this type of analysis and describe how we analyzed the interview data from a dyadic point of view, to share what we learned in the process.

scholarly journals Residual Hole Concentration in Recombination Centres after Bleaching

2021 ◽  
Vol 48 (1) ◽  
pp. 415-427
Author(s):  
N. K. Pawlak ◽  
A. Timar-Gabor ◽  
A. Chruścińska
Keyword(s):  
Total Dose ◽  
Hole Concentration ◽  
Transport Processes ◽  
Point Of View ◽  
Model Parameters ◽  
Sediment Dating ◽  
The Past ◽  
Wide Range ◽  
Dating Method ◽  
The Impact

Abstract Trapped charge dating method using electron spin resonance (ESR) of quartz is progressively used for sediment dating. ESR signals can be used for accurate age estimation only when these signals are zeroed by sunlight exposure before the layer creation or when one knows their ESR residual level (the part of the signal that is not bleached). It is well known that the ESR signal related to the Al-hole centres in quartz used for sediment dating has a significant residual signal. From the point of view of luminescence models, as a hole trap, the Al-hole centre is considered as a recombination centre in quartz. Recently, it was demonstrated experimentally that the ESR signal of the Al-hole centre is dependent on the total dose absorbed by the quartz sample in the past. The same effect was confirmed by simulations of the charge transport processes for a model including two recombination centres. Here, the dependence of residual hole concentration (RHC) in the recombination centres on the total dose absorbed by a sample in the past is studied in detail by computer simulations for a wide range of model parameters. The impact that the various relations of centre parameters have on the dependence of the residual as a function of dose is investigated and the implications for the dating practice are discussed.

The Geosciences Applied to Lunar Exploration

1962 ◽  
Vol 14 ◽  
pp. 169-257 ◽  
Author(s):  
J. Green
Keyword(s):  
Lunar Surface ◽  
Probable Mechanism ◽  
Point Of View ◽  
Lunar Exploration ◽  
Geological Model ◽  
Apply Geophysics ◽  
Surface Features ◽  
The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

МАРКЕТИНГОВІ АСПЕКТИ ФУНКЦІОНУВАННЯ ЛІТЕРАТУРНИХ КОНКУРСІВ ТА ПРЕМІЙ

2020 ◽  
pp. 90
Author(s):  
O. Bondar
Keyword(s):  
Publishing House ◽  
Target Audience ◽  
Point Of View ◽  
Information Support ◽  
Literary Field ◽  
Non Profit ◽  
Functional Aspects ◽  
The Media ◽  
Literary Prizes ◽  
The Impact

<p><em>In this study, I have collected and summarized the functional aspects of a literary prize, contest, and rating, which indicate their affiliation with the marketing complex of the publishing house for the first time. For this purpose, I have analyzed and summarized the common concepts of the functioning of literary prizes and contests as advertising tools for publishing activity. Because the previous studies are only focused on the fact of the impact of the prize on the promotion of editions but do not explain it, these aspects have been considered and introduced by me from the book production’s point of view. I investigated that the prizes and the contests in the literary field are effective marketing tools, which meet many publisher’s needs at the same time and can be considered a non-profit form of capital. I have reviewed the works of other authors, who accept that the economic success of the book is rising if the author is a winner of the literary prize or contest. I have found out that the book prize activates the demand for the book, and the literary contest is a tool to track the reader’s reaction to a future publication. In this way, literary prizes and contests can be considered as a way of conducting a marketing dialogue with the target audience. I have focused on the information support of literary national and international prizes and contests by the media, which attracts attention to the book and forms the reader’s interest. The literary prizes and contests are also considered as a way of exploring trends and their changes, familiarization the popular genres among the target audience and fixation the current choice of modern readers. Literary prizes and contests motivate the authors to improve their literary excellence, are the source of new authors and works, and assist in increasing sales of books. However, further research is recommended.</em></p><strong><em>Key words:</em></strong><em> book prize, book rating, literary contest, literary prize, functions of the literary prizes.</em>

On the Impact of Aptness, Conventionality and Familiarity on Metaphor Processing from a Meta-analytical Point of View

2020 ◽  
Vol 6 (1) ◽  
pp. 55-106
Author(s):  
Csilla Rákosi
Keyword(s):  
Meta Analysis ◽  
Point Of View ◽  
Psycholinguistic Research ◽  
Analytical Point ◽  
Metaphor Processing ◽  
The Impact

Psycholinguistic research into metaphor processing is burdened with empirical problems as experiments provide diverging evidence on the impact of conventionality, familiarity and aptness, and with conceptual issues as the interpretation and operationalization of the three concepts mentioned, as well as the related predictions which can be drawn from theories of metaphor processing, are controversial in the literature. This paper uses tools of statistical meta-analysis in order to bring us closer to the solution of these problems and reveal future lines of research.

Estimating OLED Display Device Lifetime from pixel and screen brightness and its application

2019 ◽  
Vol 2019 (1) ◽  
pp. 331-338 ◽  
Author(s):  
Jérémie Gerhardt ◽  
Michael E. Miller ◽  
Hyunjin Yoo ◽  
Tara Akhavan
Keyword(s):  
Image Processing ◽  
Power Consumption ◽  
Model Parameters ◽  
Display Device ◽  
Image Processing Algorithm ◽  
Pixel Value ◽  
Device Lifetime ◽  
The Impact ◽  
Oled Display

In this paper we discuss a model to estimate the power consumption and lifetime (LT) of an OLED display based on its pixel value and the brightness setting of the screen (scbr). This model is used to illustrate the effect of OLED aging on display color characteristics. Model parameters are based on power consumption measurement of a given display for a number of pixel and scbr combinations. OLED LT is often given for the most stressful display operating situation, i.e. white image at maximum scbr, but having the ability to predict the LT for other configurations can be meaningful to estimate the impact and quality of new image processing algorithms. After explaining our model we present a use case to illustrate how we use it to evaluate the impact of an image processing algorithm for brightness adaptation.

Wacana Kolonial dalam Novel Max Havelaar: Sebuah Kajian Poskolonial

Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 411
Author(s):  
Abu Bakar Ramadhan Muhamad
Keyword(s):  
Point Of View ◽  
The Other ◽  
The Novel ◽  
Colonial Discourse ◽  
The Impact ◽  
The Voice

AbstrakHegemoni kolonialisme dalam budaya poskolonial merupakan alasan penelitian inikemudian mengkaji wacana kolonial dalam novel Max Havellar (MH) khususnya dampakditimbulkannya. Dampak dimaksud adalah posisi keberpihakan pemikiran tersirat darikarya tersebut. Hasil pembahasan menunjukkan, secara temporal maupun permanen MHmenyuarakan ketidakadilan dalam kondisi-kondisi kolonial menyangkut penindasan sangpenjajah terhadap terjajah. Hanya saja, upaya mengatasnamakan atau mewakili suarakaum terjajah terbukti mengimplikasikan ciri ideologis statis kerangka kolonialisme(orientalisme); yakni cara pandang Eropasentris, di mana “Barat” sebagai self adalah superior,dan “Timur” sebagai other adalah inferior. Dalam konteks poskolonialisme, MH dengan sifatkritisnya yang berupaya “menyuarakan” nasib pribumi terjajah, justru menampilkan stigmapenguatan kolonialitas itu sendiri secara hegemonik. Artinya, “menyuarakan” nasib pribumidimaknai sebagai keberpihankan kolonial yang kontradiktif, di mana stigma penguatankolonialitas justru lebih terasa, ujung-ujungnya melanggengkan hegemoni kolonial. Tidakmembela yang terjajah, tetapi memperhalus cara kerja mesin kolonial.AbstractThe hegemony of colonialism in the culture of postcolonial society is the reason this studythen examines the colonial discourse in the novel Max Havellar (MH) in particular the impactit brings. The impact in question is the implied position of thought in the work. The resultsof the discussion show that, temporarily or permanently, MH voiced injustice in the colonialconditions regarding the oppression of the colonist against the colonized. However, the effort toname or represent the voice of the colonized has proven to imply a static ideological characterin the framework of colonialism (orientalism); ie Eropacentric point of view, in which “West” asself is superior, and “East” as the other is the inferior. In the context of postcolonialism, MH withits critical nature that seeks to “voice” the fate of the colonized natives, actually presents thestigma of strengthening coloniality itself hegemonicly. That is, “voicing” the fate of the pribumiis interpreted as a contradictory colonial flare, where the stigma of strengthening colonialityis more pronounced, which ultimately perpetuates the hegemony of colonialism. No longerdefending the colonized, but refining the workings of the colonial machinery.

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