4,834 research outputs found

    Geological investigation of palaeotsunamis in the Samoan islands: interim report and research directions

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    The Komandorsky seismic gap has distinctive boundaries and a length of 650 km. Its period of “seismic silence” comes close to the maximum recurrence interval for great earthquakes in the Aleutian Island Arc - the stress concentration here probably having reached the critical value. So,estimation of possible earthquake and tsunami characteristics within this gap becomes a significant problem. The closest analog of a similar gap is the area where the 2004 Sumatra-Andaman catastrophic event occurred. Thus, for the present study we used the same modeling scheme as we used for that event. It was assumed that a source length of 650 km, consisting of 9 blocks, and an earthquake with a moment magnitude MW=8.5. Several block motion scenarios were considered. The tsunami generation and propagation in the Pacific Ocean and the possible wave characteristics on near and far-field coasts were estimated. Modeling of such an event showed that the wave heights on different Pacific coasts will vary from 3 to 9 meters. A tsunami wave with a 9-meter height is capable in causing significant loss of human life and economic damage.© 2013, Tsunami Society International

    Magnetic Excitations in the Quasi-1D Ising-like Antiferromagnet TlCoCl3_3

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    Neutron inelastic scattering measurements have been performed in order to investigate the magnetic excitations in the quasi-1D Ising-like antiferromagnet TlCoCl3_3. We observed the magnetic excitation, which corresponds to the spin-wave excitation continuum corresponding to the domain-wall pair excitation in the 1D Ising-like antiferromagnet. According to the Ishimura-Shiba theory, we analyzed the observed spin-wave excitation, and the exchange constant 2J2J and the anistropy ϵ\epsilon were estimated as 14.7 meV and 0.14 in TlCoCl3_3, respectively.Comment: 2 pages, 3 figures, jpsj2.cls, to be published in J. Phys. Soc. Jpn. Vol.75 (2006) No.

    Optimal representation of our knowledge about seismic sources for PSHA in low deformation areas

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    characterization of the seismic sources, the definition of the attenuation law and the computation of the probabilistic seismic hazard. Our work is focus on the first two steps. Given that most active faults are not characterized well enough, in low deformation areas, seismic sources are generally defined as areal zones, delimited with finite boundary polygons, within which the geological features of active tectonics and the seismicity are deemed homogeneous. Besides the lack of data (e.g., narrow range of recorded magnitudes), the application of this representation generates different problems: 1) a large sensitivity of resulting hazard maps on the location of zone boundaries, while these boundaries are set by expert decision; 2) the zoning can not represent any variation in faulting mechanism; 3) the seismicity rates are distributed throughout the zones and we lose the location of the determinant information used for their calculation. We propose an exploratory study for an alternative procedure in area source modeling. This method allows to obtain a limit, and its uncertainties, between two zones, separated by two different seismic activity rates. Since we obtain this limit, we can recover the seismic activity rates for both zones.The important features for this developed method is the location and magnitude of the largest earthquakes. Given than the largest events are not recorded by instruments,we decide to use the Bakun and Wentworth method (1997) to better characterize the epicentral region and the magnitude of the instrumental earthquakes. Because of the unusual shape of the isoseismal lines of the 1909 Benavente event, we decided to apply this methodology to this event. The result show that the estimated epicenter (Kárnik, 1969) is within all the confidence-level. Because of the low magnitude estimation, we decide to test the sensibility of this method to the attenuation law. A new law is developed using a compilation of macroseismic reports and will be used to re-estimate the epicentral region and the magnitude of the 1909 Benavente event.The logarithmic trends of intensities with the median distance suggests a logarithmic form for the attenuation law. Then, this law will be used to re-evaluate the estimations of both epicentral region and magnitude of the 1909 Benavente event

    Cross-Modal Health State Estimation

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    Individuals create and consume more diverse data about themselves today than any time in history. Sources of this data include wearable devices, images, social media, geospatial information and more. A tremendous opportunity rests within cross-modal data analysis that leverages existing domain knowledge methods to understand and guide human health. Especially in chronic diseases, current medical practice uses a combination of sparse hospital based biological metrics (blood tests, expensive imaging, etc.) to understand the evolving health status of an individual. Future health systems must integrate data created at the individual level to better understand health status perpetually, especially in a cybernetic framework. In this work we fuse multiple user created and open source data streams along with established biomedical domain knowledge to give two types of quantitative state estimates of cardiovascular health. First, we use wearable devices to calculate cardiorespiratory fitness (CRF), a known quantitative leading predictor of heart disease which is not routinely collected in clinical settings. Second, we estimate inherent genetic traits, living environmental risks, circadian rhythm, and biological metrics from a diverse dataset. Our experimental results on 24 subjects demonstrate how multi-modal data can provide personalized health insight. Understanding the dynamic nature of health status will pave the way for better health based recommendation engines, better clinical decision making and positive lifestyle changes.Comment: Accepted to ACM Multimedia 2018 Conference - Brave New Ideas, Seoul, Korea, ACM ISBN 978-1-4503-5665-7/18/1

    Polarized Neutron Inelastic Scattering Study of the Anisotropic Magnetic Fluctuations in the Quasi-1D Ising-like Antiferromagnet TlCoCl3_3

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    Polarized neutron inelastic scattering experiments have been carried out in the quasi-1D Ising-like antiferromagnet TlCoCl3_3. We observed the longitudinal magnetic fluctuation Szz(Q,ω)S_{zz} (Q, \omega) for the spin-wave excitation continuum, which has not been observed in the unpolarized neutron inelastic scattering experiments of the quasi-1D Ising-like antiferromagnets CsCoCl3_3 and TlCoCl3_3 so far, together with the transverse magnetic fluctuation Sxx(Q,ω)S_{xx} (Q, \omega). We compared both obtained intensities of Sxx(Q,ω)S_{xx} (Q, \omega) and Szz(Q,ω)S_{zz} (Q, \omega) with the perturbation theory from the pure Ising limit by Ishimura and Shiba, and a semi-quantitative agreement was found.Comment: 5 pages, 5 figures, jpsj2.cls, to be published in J. Phys. Soc. Jpn. Vol. 75 (2006) No.

    The Reification of Patterns in the Design of Description-Driven Systems

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    To address the issues of reusability and evolvability in designing self- describing systems, this paper proposes a pattern-based, object-oriented, description-driven system architecture. The proposed architecture embodies four pillars - first, the adoption of a multi-layered meta-modeling architecture and reflective meta-level architecture, second, the identification of four data modeling relationships that must be made explicit such that they can be examined and modified dynamically, third, the identification of five design patterns which have emerged from practice and have proved essential in providing reusable building blocks for data management, and fourth, the encoding of the structural properties of the five design patterns by means of one pattern, the Graph pattern. The CRISTAL research project served as the basis onto which the pattern-based meta-object approach has been applied. The proposed architecture allows the realization of reusability and adaptability, and is fundamental in the specification of self-describing data management components.Comment: 10 pages 11 figure

    Off-diagonal Interactions, Hund's Rules and Pair-binding in Hubbard Molecules

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    We have studied the effect of including nearest-neighbor, electron-electron interactions, in particular the off-diagonal (non density-density) terms, on the spectra of truncated tetrahedral and icosahedral ``Hubbard molecules,'' focusing on the relevance of these systems to the physics of doped C60_{60}. Our perturbation theoretic and exact diagonalization results agree with previous work in that the density-density term suppresses pair-binding. However, we find that for the parameter values of interest for C60C_{60} the off-diagonal terms {\em enhance} pair-binding, though not enough to offset the suppression due to the density-density term. We also find that the critical interaction strengths for the Hund's rules violating level crossings in C602_{60}^{-2}, C603_{60}^{-3} and C604_{60}^{-4} are quite insensitive to the inclusion of these additional interactions.Comment: 20p + 5figs, Revtex 3.0, UIUC preprint P-94-10-08

    From Design to Production Control Through the Integration of Engineering Data Management and Workflow Management Systems

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    At a time when many companies are under pressure to reduce "times-to-market" the management of product information from the early stages of design through assembly to manufacture and production has become increasingly important. Similarly in the construction of high energy physics devices the collection of (often evolving) engineering data is central to the subsequent physics analysis. Traditionally in industry design engineers have employed Engineering Data Management Systems (also called Product Data Management Systems) to coordinate and control access to documented versions of product designs. However, these systems provide control only at the collaborative design level and are seldom used beyond design. Workflow management systems, on the other hand, are employed in industry to coordinate and support the more complex and repeatable work processes of the production environment. Commercial workflow products cannot support the highly dynamic activities found both in the design stages of product development and in rapidly evolving workflow definitions. The integration of Product Data Management with Workflow Management can provide support for product development from initial CAD/CAM collaborative design through to the support and optimisation of production workflow activities. This paper investigates this integration and proposes a philosophy for the support of product data throughout the full development and production lifecycle and demonstrates its usefulness in the construction of CMS detectors.Comment: 18 pages, 13 figure
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