WorldWideScience

Sample records for seismology tip sheet

  1. Seismology

    International Nuclear Information System (INIS)

    1980-01-01

    The Norwegian Seismic Array (NORSAR) has in 1979 worked mainly on reports and investigations for the seismological expert group established in 1976 by the UN Disarmament Committee in Geneva. One of NORSAR's staff is scientific secretary for the group. Reports published by the group in 1978 and 1979 proposed a global surveillance system for nuclear explosions and NORSAR as one of the largest stations will play a central role in the proposed network. A number of other tasks have been performed by NORSAR in connection with the seismology and tectonics of the Norwegian continental shelf, a projected dam in Tanzania, a dam in S.W.Norway, seismic activityin Spitzbergen and ore prospecting in N.Norway. (JIW)

  2. Assisted crack tip flipping under Mode I thin sheet tearing

    DEFF Research Database (Denmark)

    Felter, Christian Lotz; Nielsen, Kim Lau

    2017-01-01

    Crack tip flipping, where the fracture surface alternates from side to side in roughly 45° shear bands, seems to be an overlooked propagation mode in Mode I thin sheet tearing. In fact, observations of crack tip flipping is rarely found in the literature. Unlike the already established modes...

  3. Extraterrestrial seismology

    CERN Document Server

    Tong, Vincent C H

    2015-01-01

    Seismology is a highly effective tool for investigating the internal structure of the Earth. Similar techniques have also successfully been used to study other planetary bodies (planetary seismology), the Sun (helioseismology), and other stars (asteroseismology). Despite obvious differences between stars and planetary bodies, these disciplines share many similarities and together form a coherent field of scientific research. This unique book takes a transdisciplinary approach to seismology and seismic imaging, reviewing the most recent developments in these extraterrestrial contexts. With contributions from leading scientists, this timely volume systematically outlines the techniques used in observation, data processing, and modelling for asteroseismology, helioseismology, and planetary seismology, drawing comparisons with seismic methods used in geophysics. Important recent discoveries in each discipline are presented. With an emphasis on transcending the traditional boundaries of astronomy, solar, planetary...

  4. Experimental and Numerical Investigations of Applying Tip-bottomed Tool for Bending Advanced Ultra-high Strength Steel Sheet

    Science.gov (United States)

    Mitsomwang, Pusit; Borrisutthekul, Rattana; Klaiw-awoot, Ken; Pattalung, Aran

    2017-09-01

    This research was carried out aiming to investigate the application of a tip-bottomed tool for bending an advanced ultra-high strength steel sheet. The V-die bending experiment of a dual phase steel (DP980) sheet which had a thickness of 1.6 mm was executed using a conventional bending and a tip-bottomed punches. Experimental results revealed that the springback of the bent worksheet in the case of the tip-bottomed punch was less than that of the conventional punch case. To further discuss bending characteristics, a finite element (FE) model was developed and used to simulate the bending of the worksheet. From the FE analysis, it was found that the application of the tip-bottomed punch contributed the plastic deformation to occur at the bending region. Consequently, the springback of the worksheet reduced. In addition, the width of the punch tip was found to affect the deformation at the bending region and determined the springback of the bent worksheet. Moreover, the use of the tip-bottomed punch resulted in the apparent increase of the surface hardness of the bent worksheet, compared to the bending with the conventional punch.

  5. Rotational seismology

    Science.gov (United States)

    Lee, William H K.

    2016-01-01

    Rotational seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation waves.Rotational effects of seismic waves, together with rotations caused by soil–structure interaction, have been observed for centuries (e.g., rotated chimneys, monuments, and tombstones). Figure 1a shows the rotated monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres rotated about 15° relative to the base. The study of rotational seismology began only recently when sensitive rotational sensors became available due to advances in aeronautical and astronomical instrumentations.

  6. [TIPS

    Science.gov (United States)

    Brazzini, Augusto; Carrillo, Alvaro; Cantella, Raúl

    1998-01-01

    Esophageal hemorrage due to variceal bleeding in cirrhotic patients represents a serious problem for the physician in charge, especially in this country where liver transplants are inexistent; and also, it is a drama for the patient and its familly. We propose here the Transjugular Intrahepatic Portosystemic Shunt (TIPS). Twenty one patients were part of a study where 23 TIPS were placed, observing an immediate improval in 18 of them, a rebleeding in 2, within the first 24 and 48 hours. An embolization of the coronary veins was performed in the procedure in 15 patients, and a second intervention due to rebleeding in 2 of them. In the latter patients, the embolization of the coronary veins was rutinary.The survival of the patients has been outstanding.We conclude that this interventional procedure is a worldwide reality in the treatment of esophageal hemorrage by variceal bleeding due to portal hipertension, and it does not cut down the probability of liver transplant, unfortunately inexistent in our country. This procedure results in a low morbimortality with an adequate quality of life.

  7. Citizen Seismology

    Science.gov (United States)

    Bossu, Rémy; Gilles, Sébastien; Mazet-Roux, Gilles; Kamb, Linus; Frobert, Laurent

    2010-05-01

    In science, projects which involve volunteers for observations, measurements, computation are grouped under the term, Citizen Science. They range from bird or planet census to distributing computing on volonteers's computer. Over the last five years, the EMSC has been developing tools and strategy to collect information on earthquake's impact from the first persons to be informed, i.e. the witnesses. By extension, it is named Citizen Seismology. The European Mediterranean Seismological Centre (EMSC), a scientific not-for-profit NGO, benefits from the high visibility of its rapid earthquake information services (www.emsc-csem.org) which attract an average of more than half a million visits a month from 160 countries. Witnesses converge to its site within a couple of minutes of earthquake's occurrence to find out information about the cause of the shaking they have just been through. The convergence generates brutal increases of hit rate which can be automatically detected. They are often the first indication about the occurrence of a felt event. Witnesses' locations are determined from their IP addresses. Localities exhibiting statistically significant increase of traffic are mapped to produce the "felt map". This map available within 5 to 8 minutes of the earthquake's occurrence represents the area where the event was felt. It is the fastest way to collect in-situ information on the consequences of an earthquake. Widespread damage region are expected to be mapped through a significant lack or absence of visitors. A second tool involving the visitors is an online macroseismic questionnaire available in 21 languages. It complements the felt maps as it can describes the level of shaking or damage, but is only available in 90 to 120 minutes. Witnesses can also share their pictures of damage. They used it also to provide us exceptional pictures of transient phenomena. With the University of Edinburgh, we are finalising a prototype named ShakemApple, linking Apple

  8. Volcano seismology

    Science.gov (United States)

    Chouet, B.

    2003-01-01

    A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of portable broadband seismic instrumentation, availability of digital networks with wide dynamic range, and development of new powerful analysis techniques, rapid progress is being made toward a synthesis of high-quality seismic data to develop a coherent model of eruption mechanics. Examples of recent advances are: (1) high-resolution tomography to image subsurface volcanic structures at scales of a few hundred meters; (2) use of small-aperture seismic antennas to map the spatio-temporal properties of long-period (LP) seismicity; (3) moment tensor inversions of very-long-period (VLP) data to derive the source geometry and mass-transport budget of magmatic fluids; (4) spectral analyses of LP events to determine the acoustic properties of magmatic and associated hydrothermal fluids; and (5) experimental modeling of the source dynamics of volcanic tremor. These promising advances provide new insights into the mechanical properties of volcanic fluids and subvolcanic mass-transport dynamics. As new seismic methods refine our understanding of seismic sources, and geochemical methods better constrain mass balance and magma behavior, we face new challenges in elucidating the physico-chemical processes that cause volcanic unrest and its seismic and gas-discharge manifestations. Much work remains to be done toward a synthesis of seismological, geochemical, and petrological observations into an integrated model of volcanic behavior. Future important goals must include: (1) interpreting the key types of magma movement, degassing and boiling events that produce characteristic seismic phenomena; (2) characterizing multiphase fluids in subvolcanic

  9. Know Your School District: Tips for Parents. PACER Center ACTion Information Sheets. PHP-c112

    Science.gov (United States)

    PACER Center, 2006

    2006-01-01

    Becoming familiar with the school district will help parents become active and involved partners in their child's education. Research has demonstrated that family involvement in children's education can boost their academic success. Knowing about the following areas, which are discussed in this information sheet, can help parental involvement at…

  10. Seismology of the Jupiter

    International Nuclear Information System (INIS)

    Vorontsov, S.V.; Gudkova, T.V.; Zharkov, V.N.

    1989-01-01

    The structure and diagnostic properties of the spectrum of free oscillations of the models of the Jupiter are discussed. The spectrum is very sensitive to the properties of the inner core and density discontinuities in the interior of the planet. It is shown that in seismology of the Jupiter unlike to solar seismology, it is not possible to use the asymptotic theory for investigation of the high-frequency part of the acoustic spectrum

  11. Jesuits in seismology

    Science.gov (United States)

    Linehan, D.

    1984-01-01

    Jesuits have been involved with scientific endeavors since the 16th century, although their association with seismology is more recent. What impelled Jesuit priests to also become seismologists is am matter of conjecture. Certainly the migration of missionaries to various parts of the world must have resulted in queries to their fellow Jesuits in Europe. What caused earthquakes? Could they be predicted? Were they connected with the weather?

  12. Controlled Noise Seismology

    KAUST Repository

    Hanafy, Sherif M.

    2015-08-19

    We use controlled noise seismology (CNS) to generate surface waves, where we continuously record seismic data while generating artificial noise along the profile line. To generate the CNS data we drove a vehicle around the geophone line and continuously recorded the generated noise. The recorded data set is then correlated over different time windows and the correlograms are stacked together to generate the surface waves. The virtual shot gathers reveal surface waves with moveout velocities that closely approximate those from active source shot gathers.

  13. The Colombia Seismological Network

    Science.gov (United States)

    Blanco Chia, J. F.; Poveda, E.; Pedraza, P.

    2013-05-01

    The latest seismological equipment and data processing instrumentation installed at the Colombia Seismological Network (RSNC) are described. System configuration, network operation, and data management are discussed. The data quality and the new seismological products are analyzed. The main purpose of the network is to monitor local seismicity with a special emphasis on seismic activity surrounding the Colombian Pacific and Caribbean oceans, for early warning in case a Tsunami is produced by an earthquake. The Colombian territory is located at the South America northwestern corner, here three tectonic plates converge: Nazca, Caribbean and the South American. The dynamics of these plates, when resulting in earthquakes, is continuously monitored by the network. In 2012, the RSNC registered in 2012 an average of 67 events per day; from this number, a mean of 36 earthquakes were possible to be located well. In 2010 the network was also able to register an average of 67 events, but it was only possible to locate a mean of 28 earthquakes daily. This difference is due to the expansion of the network. The network is made up of 84 stations equipped with different kind of broadband 40s, 120s seismometers, accelerometers and short period 1s sensors. The signal is transmitted continuously in real-time to the Central Recording Center located at Bogotá, using satellite, telemetry, and Internet. Moreover, there are some other stations which are required to collect the information in situ. Data is recorded and processed digitally using two different systems, EARTHWORM and SEISAN, which are able to process and share the information between them. The RSNC has designed and implemented a web system to share the seismological data. This innovative system uses tools like Java Script, Oracle and programming languages like PHP to allow the users to access the seismicity registered by the network almost in real time as well as to download the waveform and technical details. The coverage

  14. Controlled Noise Seismology

    KAUST Repository

    Hanafy, Sherif M.; AlTheyab, Abdullah; Schuster, Gerard T.

    2015-01-01

    We use controlled noise seismology (CNS) to generate surface waves, where we continuously record seismic data while generating artificial noise along the profile line. To generate the CNS data we drove a vehicle around the geophone line and continuously recorded the generated noise. The recorded data set is then correlated over different time windows and the correlograms are stacked together to generate the surface waves. The virtual shot gathers reveal surface waves with moveout velocities that closely approximate those from active source shot gathers.

  15. Understanding and Observing Subglacial Friction Using Seismology

    Science.gov (United States)

    Tsai, V. C.

    2017-12-01

    Glaciology began with a focus on understanding basic mechanical processes and producing physical models that could explain the principal observations. Recently, however, more attention has been paid to the wealth of recent observations, with many modeling efforts relying on data assimilation and empirical scalings, rather than being based on first-principles physics. Notably, ice sheet models commonly assume that subglacial friction is characterized by a "slipperiness" coefficient that is determined by inverting surface velocity observations. Predictions are usually then made by assuming these slipperiness coefficients are spatially and temporally fixed. However, this is only valid if slipperiness is an unchanging material property of the bed and, despite decades of work on subglacial friction, it has remained unclear how to best account for such subglacial physics in ice sheet models. Here, we describe how basic seismological concepts and observations can be used to improve our understanding and determination of subglacial friction. First, we discuss how standard models of granular friction can and should be used in basal friction laws for marine ice sheets, where very low effective pressures exist. We show that under realistic West Antarctic Ice Sheet conditions, standard Coulomb friction should apply in a relatively narrow zone near the grounding line and that this should transition abruptly as one moves inland to a different, perhaps Weertman-style, dependence of subglacial stress on velocity. We show that this subglacial friction law predicts significantly different ice sheet behavior even as compared with other friction laws that include effective pressure. Secondly, we explain how seismological observations of water flow noise and basal icequakes constrain subglacial physics in important ways. Seismically observed water flow noise can provide constraints on water pressures and channel sizes and geometry, leading to important data on subglacial friction

  16. Geology and seismology

    International Nuclear Information System (INIS)

    Schneider, J.F.; Blanc, B.

    1980-01-01

    For the construction of nuclear power stations, comprehensive site investigations are required to assure the adequacy and suitability of the site under consideration, as well as to establish the basic design data for designing and building the plant. The site investigations cover mainly the following matters: geology, seismology, hydrology, meteorology. Site investigations for nuclear power stations are carried out in stages in increasing detail and to an appreciable depth in order to assure the soundness of the project, and, in particular, to determine all measures required to assure the safety of the nuclear power station and the protection of the population against radiation exposure. The aim of seismological investigations is to determine the strength of the vibratory ground motion caused by an expected strong earthquake in order to design the plant resistant enough to take up these vibrations. In addition, secondary effects of earthquakes, such as landslides, liquefaction, surface faulting, etc. must be studied. For seashore sites, the tsunami risk must be evaluated. (orig.)

  17. Forensic seismology revisited

    Science.gov (United States)

    Douglas, A.

    2007-01-01

    contrast simple, comprising one or two cycles of large amplitude followed by a low-amplitude coda. Earthquake signals on the other hand were often complex with numerous arrivals of similar amplitude spread over 35 s or more. It therefore appeared that earthquakes could be recognised on complexity. Later however, complex explosion signals were observed which reduced the apparent effectiveness of complexity as a criterion for identifying earthquakes. Nevertheless, the AWE Group concluded that for many paths to teleseismic distances, Earth is transparent for P signals and this provides a window through which source differences will be most clearly seen. Much of the research by the Group has focused on understanding the influence of source type on P seismograms recorded at teleseismic distances. Consequently the paper concentrates on teleseismic methods of distinguishing between explosions and earthquakes. One of the most robust criteria for discriminating between earthquakes and explosions is the m b : M s criterion which compares the amplitudes of the SP P waves as measured by the body-wave magnitude m b, and the long-period (LP: ˜0.05 Hz) Rayleigh-wave amplitude as measured by the surface-wave magnitude M s; the P and Rayleigh waves being the main wave types used in forensic seismology. For a given M s, the m b for explosions is larger than for most earthquakes. The criterion is difficult to apply however, at low magnitude (say m b fail. Consequently the AWE Group in cooperation with the University of Cambridge used seismogram modelling to try and understand what controls complexity of SP P seismograms, and to put the m b : M s criterion on a theoretical basis. The results of this work show that the m b : M s criterion is robust because several factors contribute to the separation of earthquakes and explosions. The principal reason for the separation however, is that for many orientations of the earthquake source there is at least one P nodal plane in the teleseismic

  18. Bucharest urban seismology

    International Nuclear Information System (INIS)

    Balan, Stefan Florin; Ritter, Joachim R.R.

    2005-01-01

    An important project was carried out in Bucharest area by the National Institute of Research-Development for Earth Physics and Collaborative Research Center 461 (CRC 461) Geophysical Institute from the University of Karlsruhe (Germany) in the period October 2003 - August 2004. The project consists of an array of 33 stations, uniformly arranged in the city of Bucharest and in the outskirts (Magurele, Voluntari, Otopeni, Buftea, etc). The station functioned 24 h/day for a period of 10 months. The number of functioning stations had a little variation in time, some of them had to be moved because some sites became improper in time. The sensors used by the stations were of the type: STS - 2, LE - 3D, 4OT, 3ESP and KS2000. The performance of continuous recording was possible by using on each station a hard disk drive of 120 Gb, which gives independence of 3 month. For preventing some accidental electric power stops a rechargeable battery on each station was used . A service was performed for each station every month to avoid accidental stops, which consisted usually of mechanical bumps. All the recorded data by the stations was saved on DVSs, the final number being around 140. This project helped gathering a large number of seismological data for the city of Bucharest and outskirts from seismic events of magnitude of 4, 3, 2 and ambient noise. (authors)

  19. Seismology Outreach in Alaska

    Science.gov (United States)

    Gardine, L.; Tape, C.; West, M. E.

    2014-12-01

    Despite residing in a state with 75% of North American earthquakes and three of the top 15 ever recorded, most Alaskans have limited knowledge about the science of earthquakes. To many, earthquakes are just part of everyday life, and to others, they are barely noticed until a large event happens, and often ignored even then. Alaskans are rugged, resilient people with both strong independence and tight community bonds. Rural villages in Alaska, most of which are inaccessible by road, are underrepresented in outreach efforts. Their remote locations and difficulty of access make outreach fiscally challenging. Teacher retention and small student bodies limit exposure to science and hinder student success in college. The arrival of EarthScope's Transportable Array, the 50th anniversary of the Great Alaska Earthquake, targeted projects with large outreach components, and increased community interest in earthquake knowledge have provided opportunities to spread information across Alaska. We have found that performing hands-on demonstrations, identifying seismological relevance toward career opportunities in Alaska (such as natural resource exploration), and engaging residents through place-based experience have increased the public's interest and awareness of our active home.

  20. Sports Injury Prevention Tip Sheet

    Science.gov (United States)

    ... this site from a secured browser on the server. Please enable scripts and reload this page. Early Career Pediatric Trainees Medical Students International HealthyChildren.org Become a Member Sign In Professional Resources Practice Transformation Economics of Healthcare Managing Your ...

  1. Seismological Constraints on Geodynamics

    Science.gov (United States)

    Lomnitz, C.

    2004-12-01

    Earth is an open thermodynamic system radiating heat energy into space. A transition from geostatic earth models such as PREM to geodynamical models is needed. We discuss possible thermodynamic constraints on the variables that govern the distribution of forces and flows in the deep Earth. In this paper we assume that the temperature distribution is time-invariant, so that all flows vanish at steady state except for the heat flow Jq per unit area (Kuiken, 1994). Superscript 0 will refer to the steady state while x denotes the excited state of the system. We may write σ 0=(J{q}0ṡX{q}0)/T where Xq is the conjugate force corresponding to Jq, and σ is the rate of entropy production per unit volume. Consider now what happens after the occurrence of an earthquake at time t=0 and location (0,0,0). The earthquake introduces a stress drop Δ P(x,y,z) at all points of the system. Response flows are directed along the gradients toward the epicentral area, and the entropy production will increase with time as (Prigogine, 1947) σ x(t)=σ 0+α {1}/(t+β )+α {2}/(t+β )2+etc A seismological constraint on the parameters may be obtained from Omori's empirical relation N(t)=p/(t+q) where N(t) is the number of aftershocks at time t following the main shock. It may be assumed that p/q\\sim\\alpha_{1}/\\beta times a constant. Another useful constraint is the Mexican-hat geometry of the seismic transient as obtained e.g. from InSAR radar interferometry. For strike-slip events such as Landers the distribution of \\DeltaP is quadrantal, and an oval-shaped seismicity gap develops about the epicenter. A weak outer triggering maxiμm is found at a distance of about 17 fault lengths. Such patterns may be extracted from earthquake catalogs by statistical analysis (Lomnitz, 1996). Finally, the energy of the perturbation must be at least equal to the recovery energy. The total energy expended in an aftershock sequence can be found approximately by integrating the local contribution over

  2. Mathematical treatment of seismologic data

    International Nuclear Information System (INIS)

    Gama, C.A.J.V.D. da

    The principle methods of seismologic data treatment with application in engineering design, emphasizing the need for the utilization of reliable data, appropriate algorithims and rigorous calculations so that correct results and valid conclusions be achieved, are examined. (E.G.) [pt

  3. Seismological programs in Costa Rica

    Science.gov (United States)

    Montero, W.; Spall, Henry

    1983-01-01

    At the beginning of the 1970's, a series of programs in seismology were initiated by different Costa Rican institutions, and some of these programs are still in the process of development. The institutions are Insituto Costaricense de Electricidad (ICE)- The Costa Rica Institute of Electricity

  4. Tips for TIPS

    NARCIS (Netherlands)

    Cuijpers, C.F.

    2015-01-01

    The transjugular intrahepatic portosystemic shunt (TIPS) procedure is one of the most technically challenging procedures in interventional radiology. During the procedure, interventional radiologists (IRs) insert very thin and long instruments through a little incision in the patient’s neck. They

  5. Web Based Seismological Monitoring (wbsm)

    Science.gov (United States)

    Giudicepietro, F.; Meglio, V.; Romano, S. P.; de Cesare, W.; Ventre, G.; Martini, M.

    Over the last few decades the seismological monitoring systems have dramatically improved tanks to the technological advancements and to the scientific progresses of the seismological studies. The most modern processing systems use the network tech- nologies to realize high quality performances in data transmission and remote controls. Their architecture is designed to favor the real-time signals analysis. This is, usually, realized by adopting a modular structure that allow to easy integrate any new cal- culation algorithm, without affecting the other system functionalities. A further step in the seismic processing systems evolution is the large use of the web based appli- cations. The web technologies can be an useful support for the monitoring activities allowing to automatically publishing the results of signals processing and favoring the remote access to data, software systems and instrumentation. An application of the web technologies to the seismological monitoring has been developed at the "Os- servatorio Vesuviano" monitoring center (INGV) in collaboration with the "Diparti- mento di Informatica e Sistemistica" of the Naples University. A system named Web Based Seismological Monitoring (WBSM) has been developed. Its main objective is to automatically publish the seismic events processing results and to allow displaying, analyzing and downloading seismic data via Internet. WBSM uses the XML tech- nology for hypocentral and picking parameters representation and creates a seismic events data base containing parametric data and wave-forms. In order to give tools for the evaluation of the quality and reliability of the published locations, WBSM also supplies all the quality parameters calculated by the locating program and allow to interactively display the wave-forms and the related parameters. WBSM is a modular system in which the interface function to the data sources is performed by two spe- cific modules so that to make it working in conjunction with a

  6. Tipping Point

    Medline Plus

    Full Text Available ... death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ... tv tip-overs. The force of a large television falling from tipping furniture can be staggering. A ...

  7. CPAP Tips

    Science.gov (United States)

    ... now Try it free Find out why Close CPAP Tips from FDA USFoodandDrugAdmin Loading... Unsubscribe from USFoodandDrugAdmin? ... apnea and use a continuous positive airway pressure (CPAP) device when sleeping? Here are some tips from ...

  8. Tipping Point

    Medline Plus

    Full Text Available ... and furniture, appliance and tv tip-overs. The force of a large television falling from tipping furniture ... 50 lb. TV falls with about the same force as child falling from the third story of ...

  9. Tipping Point

    Medline Plus

    Full Text Available ... Tipping Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture ... about horrible accidents involving young children and furniture, appliance and tv tip-overs. The force of a ...

  10. Tipping Point

    Medline Plus

    Full Text Available ... en español Blog About OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by ... danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe ...

  11. CFD analysis of cloud cavitation on three tip-modified propellers with systematically varied tip geometry

    DEFF Research Database (Denmark)

    Shin, K. W.; Andersen, Poul

    2015-01-01

    The blade tip loading is often reduced as an effort to restrain sheet and tip vortex cavitation in the design of marine propellers. This CFD analysis demonstrates that an excessive reduction of the tip loading can cause cloud cavitation responsible for much of noise and surface erosion. Detached...

  12. Global teaching of global seismology

    Science.gov (United States)

    Stein, S.; Wysession, M.

    2005-12-01

    Our recent textbook, Introduction to Seismology, Earthquakes, & Earth Structure (Blackwell, 2003) is used in many countries. Part of the reason for this may be our deliberate attempt to write the book for an international audience. This effort appears in several ways. We stress seismology's long tradition of global data interchange. Our brief discussions of the science's history illustrate the contributions of scientists around the world. Perhaps most importantly, our discussions of earthquakes, tectonics, and seismic hazards take a global view. Many examples are from North America, whereas others are from other areas. Our view is that non-North American students should be exposed to North American examples that are type examples, and that North American students should be similarly exposed to examples elsewhere. For example, we illustrate how the Euler vector geometry changes a plate boundary from spreading, to strike-slip, to convergence using both the Pacific-North America boundary from the Gulf of California to Alaska and the Eurasia-Africa boundary from the Azores to the Mediterranean. We illustrate diffuse plate boundary zones using western North America, the Andes, the Himalayas, the Mediterranean, and the East Africa Rift. The subduction zone discussions examine Japan, Tonga, and Chile. We discuss significant earthquakes both in the U.S. and elsewhere, and explore hazard mitigation issues in different contexts. Both comments from foreign colleagues and our experience lecturing overseas indicate that this approach works well. Beyond the specifics of our text, we believe that such a global approach is facilitated by the international traditions of the earth sciences and the world youth culture that gives students worldwide common culture. For example, a video of the scene in New Madrid, Missouri that arose from a nonsensical earthquake prediction in 1990 elicits similar responses from American and European students.

  13. Seismology and space-based geodesy

    Science.gov (United States)

    Tralli, David M.; Tajima, Fumiko

    1993-01-01

    The potential of space-based geodetic measurement of crustal deformation in the context of seismology is explored. The achievements of seismological source theory and data analyses, mechanical modeling of fault zone behavior, and advances in space-based geodesy are reviewed, with emphasis on realizable contributions of space-based geodetic measurements specifically to seismology. The fundamental relationships between crustal deformation associated with an earthquake and the geodetically observable data are summarized. The response and spatial and temporal resolution of the geodetic data necessary to understand deformation at various phases of the earthquake cycle is stressed. The use of VLBI, SLR, and GPS measurements for studying global geodynamics properties that can be investigated to some extent with seismic data is discussed. The potential contributions of continuously operating strain monitoring networks and globally distributed geodetic observatories to existing worldwide modern digital seismographic networks are evaluated in reference to mutually addressable problems in seismology, geophysics, and tectonics.

  14. CPAP Tips

    Medline Plus

    Full Text Available ... now Try it free Find out why Close CPAP Tips from FDA USFoodandDrugAdmin Loading... Unsubscribe from USFoodandDrugAdmin? ... apnea and use a continuous positive airway pressure (CPAP) device when sleeping? Here are some tips from ...

  15. Technology Tips

    Science.gov (United States)

    Mathematics Teacher, 2004

    2004-01-01

    Some inexpensive or free ways that enable to capture and use images in work are mentioned. The first tip demonstrates the methods of using some of the built-in capabilities of the Macintosh and Windows-based PC operating systems, and the second tip describes methods to capture and create images using SnagIt.

  16. Tipping Point

    Medline Plus

    Full Text Available ... OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point ... 24 hours a day. For young children whose home is a playground, it’s the best way to ...

  17. Tipping Point

    Medline Plus

    Full Text Available ... 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ...

  18. Bulgarian National Digital Seismological Network

    Science.gov (United States)

    Dimitrova, L.; Solakov, D.; Nikolova, S.; Stoyanov, S.; Simeonova, S.; Zimakov, L. G.; Khaikin, L.

    2011-12-01

    The Bulgarian National Digital Seismological Network (BNDSN) consists of a National Data Center (NDC), 13 stations equipped with RefTek High Resolution Broadband Seismic Recorders - model DAS 130-01/3, 1 station equipped with Quanterra 680 and broadband sensors and accelerometers. Real-time data transfer from seismic stations to NDC is realized via Virtual Private Network of the Bulgarian Telecommunication Company. The communication interruptions don't cause any data loss at the NDC. The data are backed up in the field station recorder's 4Mb RAM memory and are retransmitted to the NDC immediately after the communication link is re-established. The recorders are equipped with 2 compact flash disks able to save more than 1 month long data. The data from the flash disks can be downloaded remotely using FTP. The data acquisition and processing hardware redundancy at the NDC is achieved by two clustered SUN servers and two Blade Workstations. To secure the acquisition, processing and data storage processes a three layer local network is designed at the NDC. Real-time data acquisition is performed using REFTEK's full duplex error-correction protocol RTPD. Data from the Quanterra recorder and foreign stations are fed into RTPD in real-time via SeisComP/SeedLink protocol. Using SeisComP/SeedLink software the NDC transfers real-time data to INGV-Roma, NEIC-USA, ORFEUS Data Center. Regional real-time data exchange with Romania, Macedonia, Serbia and Greece is established at the NDC also. Data processing is performed by the Seismic Network Data Processor (SNDP) software package running on the both Servers. SNDP includes subsystems: Real-time subsystem (RTS_SNDP) - for signal detection; evaluation of the signal parameters; phase identification and association; source estimation; Seismic analysis subsystem (SAS_SNDP) - for interactive data processing; Early warning subsystem (EWS_SNDP) - based on the first arrived P-phases. The signal detection process is performed by

  19. High-performance computing in seismology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The scientific, technical, and economic importance of the issues discussed here presents a clear agenda for future research in computational seismology. In this way these problems will drive advances in high-performance computing in the field of seismology. There is a broad community that will benefit from this work, including the petroleum industry, research geophysicists, engineers concerned with seismic hazard mitigation, and governments charged with enforcing a comprehensive test ban treaty. These advances may also lead to new applications for seismological research. The recent application of high-resolution seismic imaging of the shallow subsurface for the environmental remediation industry is an example of this activity. This report makes the following recommendations: (1) focused efforts to develop validated documented software for seismological computations should be supported, with special emphasis on scalable algorithms for parallel processors; (2) the education of seismologists in high-performance computing technologies and methodologies should be improved; (3) collaborations between seismologists and computational scientists and engineers should be increased; (4) the infrastructure for archiving, disseminating, and processing large volumes of seismological data should be improved.

  20. Tipping Point

    Medline Plus

    Full Text Available ... fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash format. Almost ... accidents involving young children and furniture, appliance and tv tip-overs. The force of a large television ...

  1. Tipping Point

    Medline Plus

    Full Text Available ... of a large television falling from tipping furniture can be staggering. A 50 lb. TV falls with ... story of a building. That kind of impact can kill a child or cause severe injuries. About ...

  2. Tipping Point

    Medline Plus

    Full Text Available ... Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head ... see news reports about horrible accidents involving young children and furniture, appliance and tv tip-overs. The ...

  3. CPAP Tips

    Medline Plus

    Full Text Available ... sleeping? Here are some tips from the U.S. Food and Drug Administration (FDA) on how to safely and effectively use your CPAP device. Category Education License Standard YouTube License Show more Show ...

  4. CPAP Tips

    Medline Plus

    Full Text Available ... opinion count. Sign in ... and use a continuous positive airway pressure (CPAP) device when sleeping? Here are some tips from the U.S. Food and Drug Administration (FDA) on how to safely ...

  5. Tipping Point

    Medline Plus

    Full Text Available ... third story of a building. That kind of impact can kill a child or cause severe injuries. ... to prevent a tip-over tragedy. Share Post Facebook Twitter Google Plus Reddit Connect with Me:  Visit ...

  6. Statistical Seismology and Induced Seismicity

    Science.gov (United States)

    Tiampo, K. F.; González, P. J.; Kazemian, J.

    2014-12-01

    While seismicity triggered or induced by natural resources production such as mining or water impoundment in large dams has long been recognized, the recent increase in the unconventional production of oil and gas has been linked to rapid rise in seismicity in many places, including central North America (Ellsworth et al., 2012; Ellsworth, 2013). Worldwide, induced events of M~5 have occurred and, although rare, have resulted in both damage and public concern (Horton, 2012; Keranen et al., 2013). In addition, over the past twenty years, the increase in both number and coverage of seismic stations has resulted in an unprecedented ability to precisely record the magnitude and location of large numbers of small magnitude events. The increase in the number and type of seismic sequences available for detailed study has revealed differences in their statistics that previously difficult to quantify. For example, seismic swarms that produce significant numbers of foreshocks as well as aftershocks have been observed in different tectonic settings, including California, Iceland, and the East Pacific Rise (McGuire et al., 2005; Shearer, 2012; Kazemian et al., 2014). Similarly, smaller events have been observed prior to larger induced events in several occurrences from energy production. The field of statistical seismology has long focused on the question of triggering and the mechanisms responsible (Stein et al., 1992; Hill et al., 1993; Steacy et al., 2005; Parsons, 2005; Main et al., 2006). For example, in most cases the associated stress perturbations are much smaller than the earthquake stress drop, suggesting an inherent sensitivity to relatively small stress changes (Nalbant et al., 2005). Induced seismicity provides the opportunity to investigate triggering and, in particular, the differences between long- and short-range triggering. Here we investigate the statistics of induced seismicity sequences from around the world, including central North America and Spain, and

  7. News Releases, Press Releases, Tip Sheet Statements

    Science.gov (United States)

    Employment and Payroll Survey of Business Owners Work from Home Our statistics highlight trends in household statistics from multiple surveys. Data Tools & Apps Main American FactFinder Census Business Builder My Classification Codes (i.e., NAICS) Economic Census Economic Indicators Economic Studies Industry Statistics

  8. Introduction: seismology and earthquake engineering in Central and South America.

    Science.gov (United States)

    Espinosa, A.F.

    1983-01-01

    Reports the state-of-the-art in seismology and earthquake engineering that is being advanced in Central and South America. Provides basic information on seismological station locations in Latin America and some of the programmes in strong-motion seismology, as well as some of the organizations involved in these activities.-from Author

  9. Satellite Remote Sensing in Seismology. A Review

    Directory of Open Access Journals (Sweden)

    Andrew A. Tronin

    2009-12-01

    Full Text Available A wide range of satellite methods is applied now in seismology. The first applications of satellite data for earthquake exploration were initiated in the ‘70s, when active faults were mapped on satellite images. It was a pure and simple extrapolation of airphoto geological interpretation methods into space. The modern embodiment of this method is alignment analysis. Time series of alignments on the Earth's surface are investigated before and after the earthquake. A further application of satellite data in seismology is related with geophysical methods. Electromagnetic methods have about the same long history of application for seismology. Stable statistical estimations of ionosphere-lithosphere relation were obtained based on satellite ionozonds. The most successful current project "DEMETER" shows impressive results. Satellite thermal infra-red data were applied for earthquake research in the next step. Numerous results have confirmed previous observations of thermal anomalies on the Earth's surface prior to earthquakes. A modern trend is the application of the outgoing long-wave radiation for earthquake research. In ‘80s a new technology—satellite radar interferometry—opened a new page. Spectacular pictures of co-seismic deformations were presented. Current researches are moving in the direction of pre-earthquake deformation detection. GPS technology is also widely used in seismology both for ionosphere sounding and for ground movement detection. Satellite gravimetry has demonstrated its first very impressive results on the example of the catastrophic Indonesian earthquake in 2004. Relatively new applications of remote sensing for seismology as atmospheric sounding, gas observations, and cloud analysis are considered as possible candidates for applications.

  10. CPAP Tips

    Medline Plus

    Full Text Available ... Get YouTube Red. Working... Not now Try it free Find out why Close CPAP Tips from FDA ... safely and effectively use your CPAP device. Category Education License Standard YouTube License Show more Show less ...

  11. Tipping Point

    Medline Plus

    Full Text Available ... to prevent a tip-over tragedy. Share Post Facebook Twitter Google Plus Reddit Connect with Me:  Visit other Web Sites Maintained by CPSC: cpsc.gov| poolsafely.gov| recalls.gov| saferproducts.gov Privacy, Security, and Legal Notice | Accessibility Policy | Open Government @ ...

  12. CPAP Tips

    Medline Plus

    Full Text Available ... starting stop Loading... Watch Queue Queue __count__/__total__ It’s YouTube. Uninterrupted. Loading... Want music and videos with ... ads? Get YouTube Red. Working... Not now Try it free Find out why Close CPAP Tips from ...

  13. CPAP Tips

    Medline Plus

    Full Text Available ... sleeping? Here are some tips from the U.S. Food and Drug Administration (FDA) on how to safely and effectively use your CPAP device. Category ... Ambulance Service 21,588 views 4:34 Obstructive Sleep Apnea ...

  14. CPAP Tips

    Medline Plus

    Full Text Available ... sleeping? Here are some tips from the U.S. Food and Drug Administration (FDA) on how to safely ... Developers +YouTube Terms Privacy Policy & Safety Send feedback Test new features Loading... Working... Sign in to add ...

  15. Tip enhancement

    CERN Document Server

    Kawata, Satoshi

    2007-01-01

    This book discusses the recent advances in the area of near-field Raman scattering, mainly focusing on tip-enhanced and surface-enhanced Raman scattering. Some of the key features covered here are the optical structuring and manipulations, single molecule sensitivity, analysis of single-walled carbon nanotubes, and analytic applications in chemistry, biology and material sciences. This book also discusses the plasmonic materials for better enhancement, and optical antennas. Further, near-field microscopy based on second harmonic generation is also discussed. Chapters have been written by some of the leading scientists in this field, who present some of their recent work in this field.·Near-field Raman scattering·Tip-enhanced Raman spectroscopy·Surface-enhanced Raman spectroscopy·Nano-photonics·Nanoanalysis of Physical, chemical and biological materials beyond the diffraction limits·Single molecule detection

  16. Seismology software: state of the practice

    Science.gov (United States)

    Smith, W. Spencer; Zeng, Zheng; Carette, Jacques

    2018-05-01

    We analyzed the state of practice for software development in the seismology domain by comparing 30 software packages on four aspects: product, implementation, design, and process. We found room for improvement in most seismology software packages. The principal areas of concern include a lack of adequate requirements and design specification documents, a lack of test data to assess reliability, a lack of examples to get new users started, and a lack of technological tools to assist with managing the development process. To assist going forward, we provide recommendations for a document-driven development process that includes a problem statement, development plan, requirement specification, verification and validation (V&V) plan, design specification, code, V&V report, and a user manual. We also provide advice on tool use, including issue tracking, version control, code documentation, and testing tools.

  17. Seismology software: state of the practice

    Science.gov (United States)

    Smith, W. Spencer; Zeng, Zheng; Carette, Jacques

    2018-02-01

    We analyzed the state of practice for software development in the seismology domain by comparing 30 software packages on four aspects: product, implementation, design, and process. We found room for improvement in most seismology software packages. The principal areas of concern include a lack of adequate requirements and design specification documents, a lack of test data to assess reliability, a lack of examples to get new users started, and a lack of technological tools to assist with managing the development process. To assist going forward, we provide recommendations for a document-driven development process that includes a problem statement, development plan, requirement specification, verification and validation (V&V) plan, design specification, code, V&V report, and a user manual. We also provide advice on tool use, including issue tracking, version control, code documentation, and testing tools.

  18. Strategic decision analysis applied to borehole seismology

    International Nuclear Information System (INIS)

    Menke, M.M.; Paulsson, B.N.P.

    1994-01-01

    Strategic Decision Analysis (SDA) is the evolving body of knowledge on how to achieve high quality in the decision that shapes an organization's future. SDA comprises philosophy, process concepts, methodology, and tools for making good decisions. It specifically incorporates many concepts and tools from economic evaluation and risk analysis. Chevron Petroleum Technology Company (CPTC) has applied SDA to evaluate and prioritize a number of its most important and most uncertain R and D projects, including borehole seismology. Before SDA, there were significant issues and concerns about the value to CPTC of continuing to work on borehole seismology. The SDA process created a cross-functional team of experts to structure and evaluate this project. A credible economic model was developed, discrete risks and continuous uncertainties were assessed, and an extensive sensitivity analysis was performed. The results, even applied to a very restricted drilling program for a few years, were good enough to demonstrate the value of continuing the project. This paper explains the SDA philosophy concepts, and process and demonstrates the methodology and tools using the borehole seismology project example. SDA is useful in the upstream industry not just in the R and D/technology decisions, but also in major exploration and production decisions. Since a major challenge for upstream companies today is to create and realize value, the SDA approach should have a very broad applicability

  19. Rotational Seismology Workshop of February 2006

    Science.gov (United States)

    Evans, John R.; Cochard, A.; Graizer, Vladimir; Huang, Bor-Shouh; Hudnut, Kenneth W.; Hutt, Charles R.; Igel, H.; Lee, William H.K.; Liu, Chun-Chi; Majewski, Eugeniusz; Nigbor, Robert; Safak, Erdal; Savage, William U.; Schreiber, U.; Teisseyre, Roman; Trifunac, Mihailo; Wassermann, J.; Wu, Chien-Fu

    2007-01-01

    Introduction A successful workshop titled 'Measuring the Rotation Effects of Strong Ground Motion' was held simultaneously in Menlo Park and Pasadena via video conference on 16 February 2006. The purpose of the Workshop and this Report are to summarize existing data and theory and to explore future challenges for rotational seismology, including free-field strong motion, structural strong motion, and teleseismic motions. We also forged a consensus on the plan of work to be pursued by this international group in the near term. At this first workshop were 16 participants in Menlo Park, 13 in Pasadena, and a few on the telephone. It was organized by William H. K. Lee and John R. Evans and chaired by William U. Savage in Menlo Park and by Kenneth W. Hudnut in Pasadena. Its agenda is given in the Appendix. This workshop and efforts in Europe led to the creation of the International Working Group on Rotational Seismology (IWGoRS), an international volunteer group providing forums for exchange of ideas and data as well as hosting a series of Workshops and Special Sessions. IWGoRS created a Web site, backed by an FTP site, for distribution of materials related to rotational seismology. At present, the FTP site contains the 2006 Workshop agenda (also given in the Appendix below) and its PowerPoint presentations, as well as many papers (reasonable-only basis with permission of their authors), a comprehensive citations list, and related information. Eventually, the Web site will become the sole authoritative source for IWGoRS and shared information: http://www.rotational-seismology.org ftp://ehzftp.wr.usgs.gov/jrevans/IWGoRS_FTPsite/ With contributions from various authors during and after the 2006 Workshop, this Report proceeds from the theoretical bases for making rotational measurements (Graizer, Safak, Trifunac) through the available observations (Huang, Lee, Liu, Nigbor), proposed suites of measurements (Hudnut), a discussion of broadband teleseismic rotational

  20. EPOS Seismology services and their users

    Science.gov (United States)

    Haslinger, Florian; Dupont, Aurelien; Michelini, Alberto; Rietbrock, Andreas; Sleeman, Reinoud; Wiemer, Stefan; Basili, Roberto; Bossu, Rémy; Cakti, Eser; Cotton, Fabrice; Crawford, Wayne; Crowley, Helen; Danciu, Laurentiu; Diaz, Jordi; Garth, Tom; Locati, Mario; Luzi, Lucia; Pitilakis, Kyriazis; Roumelioti, Zafeiria; Strollo, Angelo

    2017-04-01

    The construction of seismological community services for the European Plate Observing System Research Infrastructure (EPOS) is by now well under way. A significant number of services are already operational, largely based on those existing at established institutions or collaborations like ORFEUS, EMSC, AHEAD and EFEHR, and more are being added to be ready for internal validation by late 2017. In this presentation we focus on a number of issues related to the interaction of the community of users with the services provided by the seismological part of the EPOS research infrastructure. How users interact with a service (and how satisfied they are with this interaction) is viewed as one important component of the validation of a service within EPOS, and certainly is key to the uptake of a service and from that also it's attributed value. Within EPOS Seismology, the following aspects of user interaction have already surfaced: - user identification (and potential tracking) versus ease-of-access and openness Requesting users to identify themselves when accessing a service provides various advantages to providers and users (e.g. quantifying & qualifying the service use, customization of services and interfaces, handling access rights and quotas), but may impact the ease of access and also shy away users who don't wish to be identified for whatever reason. - service availability versus cost There is a clear and prominent connection between the availability of a service, both regarding uptime and capacity, and its operational cost (IT systems and personnel), and it is often not clear where to draw the line (and based on which considerations). In connection to that, how to best utilize third-party IT infrastructures (either commercial or public), and what the long-term cost implications of that might be, is equally open. - licensing and attribution The issue of intellectual property and associated licensing policies for data, products and services is only recently gaining

  1. Early warning of climate tipping points

    Science.gov (United States)

    Lenton, Timothy M.

    2011-07-01

    A climate 'tipping point' occurs when a small change in forcing triggers a strongly nonlinear response in the internal dynamics of part of the climate system, qualitatively changing its future state. Human-induced climate change could push several large-scale 'tipping elements' past a tipping point. Candidates include irreversible melt of the Greenland ice sheet, dieback of the Amazon rainforest and shift of the West African monsoon. Recent assessments give an increased probability of future tipping events, and the corresponding impacts are estimated to be large, making them significant risks. Recent work shows that early warning of an approaching climate tipping point is possible in principle, and could have considerable value in reducing the risk that they pose.

  2. EPOS-Seismology: building the Thematic Core Service for Seismology during the EPOS Implementation Phase

    Science.gov (United States)

    Haslinger, Florian; EPOS Seismology Consortium, the

    2015-04-01

    After the successful completion of the EPOS Preparatory Phase, the community of European Research Infrastructures in Seismology is now moving ahead with the build-up of the Thematic Core Service (TCS) for Seismology in EPOS, EPOS-Seismology. Seismology is a domain where European-level infrastructures have been developed since decades, often supported by large-scale EU projects. Today these infrastructures provide services to access earthquake waveforms (ORFEUS), parameters (EMSC) and hazard data and products (EFEHR). The existing organizations constitute the backbone of infrastructures that also in future will continue to manage and host the services of the TCS EPOS-Seismology. While the governance and internal structure of these organizations will remain active, and continue to provide direct interaction with the community, EPOS-Seismology will provide the integration of these within EPOS. The main challenge in the build-up of the TCS EPOS-Seismology is to improve and extend these existing services, producing a single framework which is technically, organizationally and financially integrated with the EPOS architecture, and to further engage various kinds of end users (e.g. scientists, engineers, public managers, citizen scientists). On the technical side the focus lies on four major tasks: - the construction of the next generation software architecture for the European Integrated (waveform) Data Archive EIDA, developing advanced metadata and station information services, fully integrate strong motion waveforms and derived parametric engineering-domain data, and advancing the integration of mobile (temporary) networks and OBS deployments in EIDA; - the further development and expansion of services to access seismological products of scientific interest as provided by the community by implementing a common collection and development (IT) platform, improvements in the earthquake information services e.g. by introducing more robust quality indicators and diversifying

  3. Decontamination sheet

    International Nuclear Information System (INIS)

    Hirose, Emiko; Kanesaki, Ken.

    1995-01-01

    The decontamination sheet of the present invention is formed by applying an adhesive on one surface of a polymer sheet and releasably appending a plurality of curing sheets. In addition, perforated lines are formed on the sheet, and a decontaminating agent is incorporated in the adhesive. This can reduce the number of curing operation steps when a plurality steps of operations for radiation decontamination equipments are performed, and further, the amount of wastes of the cured sheets, and operator's exposure are reduced, as well as an efficiency of the curing operation can be improved, and propagation of contamination can be prevented. (T.M.)

  4. WFCatalog: A catalogue for seismological waveform data

    Science.gov (United States)

    Trani, Luca; Koymans, Mathijs; Atkinson, Malcolm; Sleeman, Reinoud; Filgueira, Rosa

    2017-09-01

    This paper reports advances in seismic waveform description and discovery leading to a new seismological service and presents the key steps in its design, implementation and adoption. This service, named WFCatalog, which stands for waveform catalogue, accommodates features of seismological waveform data. Therefore, it meets the need for seismologists to be able to select waveform data based on seismic waveform features as well as sensor geolocations and temporal specifications. We describe the collaborative design methods and the technical solution showing the central role of seismic feature catalogues in framing the technical and operational delivery of the new service. Also, we provide an overview of the complex environment wherein this endeavour is scoped and the related challenges discussed. As multi-disciplinary, multi-organisational and global collaboration is necessary to address today's challenges, canonical representations can provide a focus for collaboration and conceptual tools for agreeing directions. Such collaborations can be fostered and formalised by rallying intellectual effort into the design of novel scientific catalogues and the services that support them. This work offers an example of the benefits generated by involving cross-disciplinary skills (e.g. data and domain expertise) from the early stages of design, and by sustaining the engagement with the target community throughout the delivery and deployment process.

  5. Vital Signs: Seismology of Icy Ocean Worlds.

    Science.gov (United States)

    Vance, Steven D; Kedar, Sharon; Panning, Mark P; Stähler, Simon C; Bills, Bruce G; Lorenz, Ralph D; Huang, Hsin-Hua; Pike, W T; Castillo, Julie C; Lognonné, Philippe; Tsai, Victor C; Rhoden, Alyssa R

    2018-01-01

    Ice-covered ocean worlds possess diverse energy sources and associated mechanisms that are capable of driving significant seismic activity, but to date no measurements of their seismic activity have been obtained. Such investigations could reveal the transport properties and radial structures, with possibilities for locating and characterizing trapped liquids that may host life and yielding critical constraints on redox fluxes and thus on habitability. Modeling efforts have examined seismic sources from tectonic fracturing and impacts. Here, we describe other possible seismic sources, their associations with science questions constraining habitability, and the feasibility of implementing such investigations. We argue, by analogy with the Moon, that detectable seismic activity should occur frequently on tidally flexed ocean worlds. Their ices fracture more easily than rocks and dissipate more tidal energy than the worlds also should create less thermal noise due to their greater distance and consequently smaller diurnal temperature variations. They also lack substantial atmospheres (except in the case of Titan) that would create additional noise. Thus, seismic experiments could be less complex and less susceptible to noise than prior or planned planetary seismology investigations of the Moon or Mars. Key Words: Seismology-Redox-Ocean worlds-Europa-Ice-Hydrothermal. Astrobiology 18, 37-53.

  6. a Collaborative Cyberinfrastructure for Earthquake Seismology

    Science.gov (United States)

    Bossu, R.; Roussel, F.; Mazet-Roux, G.; Lefebvre, S.; Steed, R.

    2013-12-01

    One of the challenges in real time seismology is the prediction of earthquake's impact. It is particularly true for moderate earthquake (around magnitude 6) located close to urbanised areas, where the slightest uncertainty in event location, depth, magnitude estimates, and/or misevaluation of propagation characteristics, site effects and buildings vulnerability can dramatically change impact scenario. The Euro-Med Seismological Centre (EMSC) has developed a cyberinfrastructure to collect observations from eyewitnesses in order to provide in-situ constraints on actual damages. This cyberinfrastructure takes benefit of the natural convergence of earthquake's eyewitnesses on EMSC website (www.emsc-csem.org), the second global earthquake information website within tens of seconds of the occurrence of a felt event. It includes classical crowdsourcing tools such as online questionnaires available in 39 languages, and tools to collect geolocated pics. It also comprises information derived from the real time analysis of the traffic on EMSC website, a method named flashsourcing; In case of a felt earthquake, eyewitnesses reach EMSC website within tens of seconds to find out the cause of the shaking they have just been through. By analysing their geographical origin through their IP address, we automatically detect felt earthquakes and in some cases map the damaged areas through the loss of Internet visitors. We recently implemented a Quake Catcher Network (QCN) server in collaboration with Stanford University and the USGS, to collect ground motion records performed by volunteers and are also involved in a project to detect earthquakes from ground motions sensors from smartphones. Strategies have been developed for several social media (Facebook, Twitter...) not only to distribute earthquake information, but also to engage with the Citizens and optimise data collection. A smartphone application is currently under development. We will present an overview of this

  7. ASDF - A Modern Data Format for Seismology

    Science.gov (United States)

    Krischer, Lion; Smith, James; Lei, Wenjie; Lefebvre, Matthieu; Ruan, Youyi; Sales de Andrade, Elliot; Podhorszki, Norbert; Bozdag, Ebru; Tromp, Jeroen

    2017-04-01

    Seismology as a science is driven by observing and understanding data and it is thus vital to make this as easy and accessible as possible. The growing volume of freely available data coupled with ever expanding computational power enables scientists to take on new and bigger problems. This evolution is to some part hindered as existing data formats have not been designed with it in mind. We present ASDF (http://seismic-data.org), the Adaptable Seismic Data Format, a novel, modern, and especially practical data format for all branches of seismology with particular focus on how it is incorporated into seismic full waveform inversion workflows. The format aims to solve five key issues: Efficiency: Fast I/O operations especially in high performance computing environments, especially limiting the total number of files. Data organization: Different types of data are needed for a variety of tasks. This results in ad hoc data organization and formats that are hard to maintain, integrate, reproduce, and exchange. Data exchange: We want to exchange complex and complete data sets. Reproducibility: Oftentimes just not existing but crucial to advance our science. Mining, visualization, and understanding of data: As data volumes grow, more complex, new techniques to query and visualize large datasets are needed. ASDF tackles these by defining a structure on top of HDF5 reusing as many existing standards (QuakeML, StationXML, PROV) as possible. An essential trait of ASDF is that it empowers the construction of completely self-describing data sets including waveform, station, and event data together with non-waveform data and a provenance description of everything. This for example for the first time enables the proper archival and exchange of processed or synthetic waveforms. To aid community adoption we developed mature tools in Python as well as in C and Fortran. Additionally we provide a formal definition of the format, a validation tool, and integration into widely used

  8. Solving seismological problems using sgraph program: II-waveform modeling

    International Nuclear Information System (INIS)

    Abdelwahed, Mohamed F.

    2012-01-01

    One of the seismological programs to manipulate seismic data is SGRAPH program. It consists of integrated tools to perform advanced seismological techniques. SGRAPH is considered a new system for maintaining and analyze seismic waveform data in a stand-alone Windows-based application that manipulate a wide range of data formats. SGRAPH was described in detail in the first part of this paper. In this part, I discuss the advanced techniques including in the program and its applications in seismology. Because of the numerous tools included in the program, only SGRAPH is sufficient to perform the basic waveform analysis and to solve advanced seismological problems. In the first part of this paper, the application of the source parameters estimation and hypocentral location was given. Here, I discuss SGRAPH waveform modeling tools. This paper exhibits examples of how to apply the SGRAPH tools to perform waveform modeling for estimating the focal mechanism and crustal structure of local earthquakes.

  9. Tips on Blood Testing

    Science.gov (United States)

    ... Test Pain, Discomfort and Anxiety Tips to Help Children through Their Medical Tests Tips to Help the Elderly through Their Medical Tests Find Us On Social Media: Facebook Twitter Google Plus Footer Menu Home About ...

  10. The TIPS Liquidity Premium

    DEFF Research Database (Denmark)

    Andreasen, Martin Møller; Christensen, Jens H.E.; Simon Riddell, Simon

    We introduce an arbitrage-free term structure model of nominal and real yields that accounts for liquidity risk in Treasury inflation-protected securities (TIPS). The novel feature of our model is to identify liquidity risk from individual TIPS prices by accounting for the tendency that TIPS, lik...

  11. Tip studies using CFD and comparison with tip loss models

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver; Johansen, J.

    2004-01-01

    The flow past a rotating LM8.2 blade equipped with two different tips are computed using CFD. The different tip flows are analysed and a comparison with two different tip loss models is made. Keywords: tip flow, aerodynamics, CFD......The flow past a rotating LM8.2 blade equipped with two different tips are computed using CFD. The different tip flows are analysed and a comparison with two different tip loss models is made. Keywords: tip flow, aerodynamics, CFD...

  12. Tipping elements in the Arctic marine ecosystem.

    Science.gov (United States)

    Duarte, Carlos M; Agustí, Susana; Wassmann, Paul; Arrieta, Jesús M; Alcaraz, Miquel; Coello, Alexandra; Marbà, Núria; Hendriks, Iris E; Holding, Johnna; García-Zarandona, Iñigo; Kritzberg, Emma; Vaqué, Dolors

    2012-02-01

    The Arctic marine ecosystem contains multiple elements that present alternative states. The most obvious of which is an Arctic Ocean largely covered by an ice sheet in summer versus one largely devoid of such cover. Ecosystems under pressure typically shift between such alternative states in an abrupt, rather than smooth manner, with the level of forcing required for shifting this status termed threshold or tipping point. Loss of Arctic ice due to anthropogenic climate change is accelerating, with the extent of Arctic sea ice displaying increased variance at present, a leading indicator of the proximity of a possible tipping point. Reduced ice extent is expected, in turn, to trigger a number of additional tipping elements, physical, chemical, and biological, in motion, with potentially large impacts on the Arctic marine ecosystem.

  13. Bringing Seismological Research into the School Setting

    Science.gov (United States)

    Pavlis, G. L.; Hamburger, M. W.

    2004-12-01

    One of the primary goals of educational seismology programs is to bring inquiry-based research to the middle- and high-school classroom setting. Although it is often stated as a long-term goal of science outreach programs, in practice there are many barriers to research in the school setting, among them increasing emphasis on test-oriented training, decreasing interest and participation in science fairs, limited teacher confidence and experience for mentoring research, insufficient student preparedness for research projects, and the short term of university involvement (typically limited to brief one-day encounters). For the past three+ years we have tried to address these issues through a focused outreach program we have called the PEPP Research Fellows Program. This is treated as an honors program in which high school teachers in our group nominate students with interests in science careers. These students are invited to participate in the program, and those who elect to take part participate in a one-day education and training session in the fall. Rather than leave research projects completely open, we direct the students at toward one of two specific, group-oriented projects (in our case, one focusing on local recordings of mining explosions, and a second on teleseismic body-wave analysis), but we encourage them to act as independent researchers and follow topics of interest. The students then work on seismic data from the local educational network or from the IRIS facilities. Following several months of informal interaction with teachers and students (email, web conferencing, etc.), we bring the students and teachers to our university for a weekend research symposium in the spring. Students present their work in oral or poster form and prizes are given for the best papers. Projects range from highly local projects (records of seismic noise at school X) to larger-scale regional projects (analysis of teleseismic P-wave delays at PEPP network stations) From 20 to

  14. Tsunami Ionospheric warning and Ionospheric seismology

    Science.gov (United States)

    Lognonne, Philippe; Rolland, Lucie; Rakoto, Virgile; Coisson, Pierdavide; Occhipinti, Giovanni; Larmat, Carene; Walwer, Damien; Astafyeva, Elvira; Hebert, Helene; Okal, Emile; Makela, Jonathan

    2014-05-01

    The last decade demonstrated that seismic waves and tsunamis are coupled to the ionosphere. Observations of Total Electron Content (TEC) and airglow perturbations of unique quality and amplitude were made during the Tohoku, 2011 giant Japan quake, and observations of much lower tsunamis down to a few cm in sea uplift are now routinely done, including for the Kuril 2006, Samoa 2009, Chili 2010, Haida Gwai 2012 tsunamis. This new branch of seismology is now mature enough to tackle the new challenge associated to the inversion of these data, with either the goal to provide from these data maps or profile of the earth surface vertical displacement (and therefore crucial information for tsunami warning system) or inversion, with ground and ionospheric data set, of the various parameters (atmospheric sound speed, viscosity, collision frequencies) controlling the coupling between the surface, lower atmosphere and the ionosphere. We first present the state of the art in the modeling of the tsunami-atmospheric coupling, including in terms of slight perturbation in the tsunami phase and group velocity and dependance of the coupling strength with local time, ocean depth and season. We then show the confrontation of modelled signals with observations. For tsunami, this is made with the different type of measurement having proven ionospheric tsunami detection over the last 5 years (ground and space GPS, Airglow), while we focus on GPS and GOCE observation for seismic waves. These observation systems allowed to track the propagation of the signal from the ground (with GPS and seismometers) to the neutral atmosphere (with infrasound sensors and GOCE drag measurement) to the ionosphere (with GPS TEC and airglow among other ionospheric sounding techniques). Modelling with different techniques (normal modes, spectral element methods, finite differences) are used and shown. While the fits of the waveform are generally very good, we analyse the differences and draw direction of future

  15. The Albuquerque Seismological Laboratory Data Quality Analyzer

    Science.gov (United States)

    Ringler, A. T.; Hagerty, M.; Holland, J.; Gee, L. S.; Wilson, D.

    2013-12-01

    The U.S. Geological Survey's Albuquerque Seismological Laboratory (ASL) has several efforts underway to improve data quality at its stations. The Data Quality Analyzer (DQA) is one such development. The DQA is designed to characterize station data quality in a quantitative and automated manner. Station quality is based on the evaluation of various metrics, such as timing quality, noise levels, sensor coherence, and so on. These metrics are aggregated into a measurable grade for each station. The DQA consists of a website, a metric calculator (Seedscan), and a PostgreSQL database. The website allows the user to make requests for various time periods, review specific networks and stations, adjust weighting of the station's grade, and plot metrics as a function of time. The website dynamically loads all station data from a PostgreSQL database. The database is central to the application; it acts as a hub where metric values and limited station descriptions are stored. Data is stored at the level of one sensor's channel per day. The database is populated by Seedscan. Seedscan reads and processes miniSEED data, to generate metric values. Seedscan, written in Java, compares hashes of metadata and data to detect changes and perform subsequent recalculations. This ensures that the metric values are up to date and accurate. Seedscan can be run in a scheduled task or on demand by way of a config file. It will compute metrics specified in its configuration file. While many metrics are currently in development, some are completed and being actively used. These include: availability, timing quality, gap count, deviation from the New Low Noise Model, deviation from a station's noise baseline, inter-sensor coherence, and data-synthetic fits. In all, 20 metrics are planned, but any number could be added. ASL is actively using the DQA on a daily basis for station diagnostics and evaluation. As Seedscan is scheduled to run every night, data quality analysts are able to then use the

  16. Recent achievements in real-time computational seismology in Taiwan

    Science.gov (United States)

    Lee, S.; Liang, W.; Huang, B.

    2012-12-01

    Real-time computational seismology is currently possible to be achieved which needs highly connection between seismic database and high performance computing. We have developed a real-time moment tensor monitoring system (RMT) by using continuous BATS records and moment tensor inversion (CMT) technique. The real-time online earthquake simulation service is also ready to open for researchers and public earthquake science education (ROS). Combine RMT with ROS, the earthquake report based on computational seismology can provide within 5 minutes after an earthquake occurred (RMT obtains point source information ROS completes a 3D simulation real-time now. For more information, welcome to visit real-time computational seismology earthquake report webpage (RCS).

  17. Orientation and Morphology Effects in Rapid Silicon Sheet Solidification

    Science.gov (United States)

    Ciszek, T. F.

    1984-01-01

    Radial growth anisotropies and equilibrium forms of point nucleated, dislocation free silicon sheets spreading horizontally on the free surface of a silicon melt were measured for (100), (110), (111), and (112) sheet planes. The growth process was recorded. Qualitative Wulff surface free energy polar plots were deduced from the equilibrium shapes for each sheet plane. Predicted geometries for the tip shape of unidirectional, dislocation free, horizontally grown sheets growing in various directions within the planes were analyzed. Polycrystalline sheets and dendrite propagation were analyzed. For dendrites, growth rates on the order of 2.5 m/min and growth rate anisotropies of 25 are measured.

  18. Vertically Integrated Seismological Analysis II : Inference

    Science.gov (United States)

    Arora, N. S.; Russell, S.; Sudderth, E.

    2009-12-01

    accepting such complex moves need not be hand-designed. Instead, they are automatically determined by the underlying probabilistic model, which is in turn calibrated via historical data and scientific knowledge. Consider a small seismic event which generates weak signals at several different stations, which might independently be mistaken for noise. A birth move may nevertheless hypothesize an event jointly explaining these detections. If the corresponding waveform data then aligns with the seismological knowledge encoded in the probabilistic model, the event may be detected even though no single station observes it unambiguously. Alternatively, if a large outlier reading is produced at a single station, moves which instantiate a corresponding (false) event would be rejected because of the absence of plausible detections at other sensors. More broadly, one of the main advantages of our MCMC approach is its consistent handling of the relative uncertainties in different information sources. By avoiding low-level thresholds, we expect to improve accuracy and robustness. At the conference, we will present results quantitatively validating our approach, using ground-truth associations and locations provided either by simulation or human analysts.

  19. Introduction: seismology and earthquake engineering in Mexico and Central and South America.

    Science.gov (United States)

    Espinosa, A.F.

    1982-01-01

    The results from seismological studies that are used by the engineering community are just one of the benefits obtained from research aimed at mitigating the earthquake hazard. In this issue of Earthquake Information Bulletin current programs in seismology and earthquake engineering, seismic networks, future plans and some of the cooperative programs with different internation organizations are described by Latin-American seismologists. The article describes the development of seismology in Latin America and the seismological interest of the OAS. -P.N.Chroston

  20. Research and development activities of the seismology section for the period January 1986 to December 1987

    International Nuclear Information System (INIS)

    Basu, T.K.; Murty, G.S.

    1988-01-01

    This report sumarises the R and D in Seismology during the period from January 1986 to December 1987. Major topics of current study are (1) Forensic Seismology, (2) Seismicity and Seismic Risk estimates, (3) Reservoir induced seismicity and (4) Rockburst monitoring. Considerable effort is devoted to development of seismic data acquisition systems and theoretical aspects of seismology. (author)

  1. Seismo-Live: Training in Seismology with Jupyter Notebooks

    Science.gov (United States)

    Krischer, Lion; Tape, Carl; Igel, Heiner

    2016-04-01

    Seismological training tends to occur within the isolation of a particular institution with a limited set of tools (codes, libraries) that are often not transferrable outside. Here, we propose to overcome these limitations with a community-driven library of Jupyter notebooks dedicated to training on any aspect of seismology for purposes of education and outreach, on-site or archived tutorials for codes, classroom instruction, and research. A Jupyter notebook (jupyter.org) is an open-source interactive computational environment that allows combining code execution, rich text, mathematics, and plotting. It can be considered a platform that supports reproducible research, as all inputs and outputs may be stored. Text, external graphics, equations can be handled using Markdown (incl. LaTeX) format. Jupyter notebooks are driven by standard web browsers, can be easily exchanged in text format, or converted to other documents (e.g. PDF, slide shows). They provide an ideal format for practical training in seismology. A pilot-platform was setup with a dedicated server such that the Jupyter notebooks can be run in any browser (PC, notepad, smartphone). We show the functionalities of the Seismo-Live platform with examples from computational seismology, seismic data access and processing using the ObsPy library, seismic inverse problems, and others. The current examples are all using the Python programming language but any free language can be used. Potentially, such community platforms could be integrated with the EPOS-IT infrastructure and extended to other fields of Earth sciences.

  2. ADHD: Tips to Try

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español ADHD: Tips to Try KidsHealth / For Teens / ADHD: Tips to Try Print en español TDAH: Consejos que puedes probar ADHD , short for attention deficit hyperactivity disorder , is a ...

  3. Total Telephone Tips.

    Science.gov (United States)

    Corder, Lloyd E.; And Others

    This manual of telephone behavior tips for business and sales professionals offers ways to handle the disgruntled caller and makes suggestions on topics relevant to the telephone. The manual is divided into the following sections and subsections: (1) Common Courtesy (staff tips, answering the telephone, screening calls, transferring calls, taking…

  4. Tip Cells in Angiogenesis

    NARCIS (Netherlands)

    M.G. Dallinga (Marchien); S.E.M. Boas (Sonja); I. Klaassen (Ingeborg); R.M.H. Merks (Roeland); C.J.F. van Noorden; R.O. Schlingemann (Reinier)

    2015-01-01

    htmlabstractIn angiogenesis, the process in which blood vessel sprouts grow out from a pre-existing vascular network, the so-called endothelial tip cells play an essential role. Tip cells are the leading cells of the sprouts; they guide following endothelial cells and sense their environment for

  5. Safety Tips: Basketball (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Safety Tips: Basketball KidsHealth / For Parents / Safety Tips: Basketball ... make sure they follow these tips. Why Basketball Safety Is Important Fortunately, very few basketball injuries are ...

  6. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the liver). Portal hypertension can also occur in children, although children are much less likely to require a TIPS. ... intentionally to solve the problem. Although extremely rare, children may also require a TIPS procedure. TIPS in ...

  7. Crack Tip Flipping Under Mode I/III Tearing

    DEFF Research Database (Denmark)

    Felter, Christian Lotz; Specht Jensen, Lasse; Nielsen, Kim Lau

    Crack tip flipping, where the fracture surface alternates from side to side in 45° shear bands, seems to be an overlooked propagation mode in Mode I sheet tearing often disregarded as  “transitional” or tied to randomness in the material. In fact, such observations rarely make it to the literature...

  8. Rotational Seismology: AGU Session, Working Group, and Website

    Science.gov (United States)

    Lee, William H.K.; Igel, Heiner; Todorovska, Maria I.; Evans, John R.

    2007-01-01

    Introduction Although effects of rotational motions due to earthquakes have long been observed (e. g., Mallet, 1862), nevertheless Richter (1958, p. 213) stated that: 'Perfectly general motion would also involve rotations about three perpendicular axes, and three more instruments for these. Theory indicates, and observation confirms, that such rotations are negligible.' However, Richter provided no references for this claim. Seismology is based primarily on the observation and modeling of three-component translational ground motions. Nevertheless, theoretical seismologists (e.g., Aki and Richards, 1980, 2002) have argued for decades that the rotational part of ground motions should also be recorded. It is well known that standard seismometers are quite sensitive to rotations and therefore subject to rotation-induced errors. The paucity of observations of rotational motions is mainly the result of a lack, until recently, of affordable rotational sensors of sufficient resolution. Nevertheless, in the past decade, a number of authors have reported direct observations of rotational motions and rotations inferred from rigid-body rotations in short baseline accelerometer arrays, creating a burgeoning library of rotational data. For example, ring laser gyros in Germany and New Zealand have led to the first significant and consistent observations of rotational motions from distant earthquakes (Igel et al., 2005, 2007). A monograph on Earthquake Source Asymmetry, Structural Media and Rotation Effects was published recently as well by Teisseyre et al. (2006). Measurement of rotational motions has implications for: (1) recovering the complete ground-displacement history from seismometer recordings; (2) further constraining earthquake rupture properties; (3) extracting information about subsurface properties; and (4) providing additional ground motion information to earthquake engineers for seismic design. A special session on Rotational Motions in Seismology was convened by H

  9. Broad band seismology in the Scotia region. The base Esperanza seismological observatory

    International Nuclear Information System (INIS)

    Russi, M.; Costa, G.; Febrer, J.

    1995-08-01

    The lithospheric study and the identification of relevant lateral heterogeneities in the Antarctic continent and borderlands, is essential to understand the geodynamic evolution both of the continental and oceanic bordering regions. The complexity of the geological evolution and the structural properties of the lithosphere in the Scotia area have been stressed by many authors. The present setting of the area is the result of the mutual interaction among the Antarctic, South American and several minor plants whose geodynamic history and actual boundaries are still partially unknown. The intense seismic activity that characterizes the region encourages the use of the seismological approach to investigate the lithospheric structure of the area. Since January 1992 a broad band three components station is operating at the Antarctic base Esperanza in the NE area of Antarctic Peninsula. The station has been installed with financial support of the Italian Programma Nazionale di Ricerche in Antartide (PNRA) by Osservatorio Geofisico Sperimentale (OGS) and Instituto Antartico Argentino (IAA). Russi et al. (1994) have analyzed selected recordings using the frequency-time analysis (FTAN) method obtaining some relevant information on the large scale structure of the lithosphere in the Scotia region even if data recorded by a single station were available. The extension of our analysis to further events and to horizontal component records is here presented. Within the framework of the international co-operation to the Antarctic Seismographic Network, the OGS and the IAA are upgrading the Esperanza station and installing an additional broad band station near the town of Ushuaia (Tierra del Fuego, Argentina) with the financial support of PNRA. The inversion of the dispersion curves through the FTAN of the signals recorded by an increased number of stations and generated by events with source-station paths spanning the region will allow us to extract the elastic and anelastic

  10. Lightning Safety Tips and Resources

    Science.gov (United States)

    ... Services Careers Contact Us Glossary Safety National Program Lightning Safety Tips and Resources Weather.gov > Safety > Lightning Safety Tips and Resources Lightning Resources Lightning strikes ...

  11. QuakeML - An XML Schema for Seismology

    Science.gov (United States)

    Wyss, A.; Schorlemmer, D.; Maraini, S.; Baer, M.; Wiemer, S.

    2004-12-01

    We propose an extensible format-definition for seismic data (QuakeML). Sharing data and seismic information efficiently is one of the most important issues for research and observational seismology in the future. The eXtensible Markup Language (XML) is playing an increasingly important role in the exchange of a variety of data. Due to its extensible definition capabilities, its wide acceptance and the existing large number of utilities and libraries for XML, a structured representation of various types of seismological data should in our opinion be developed by defining a 'QuakeML' standard. Here we present the QuakeML definitions for parameter databases and further efforts, e.g. a central QuakeML catalog database and a web portal for exchanging codes and stylesheets.

  12. Low Vision Tips

    Science.gov (United States)

    ... this page: https://medlineplus.gov/lowvision.html MedlinePlus: Low Vision Tips We are sorry. MedlinePlus no longer maintains the For Low Vision Users page. You will still find health resources ...

  13. Diabetes: Dental Tips

    Science.gov (United States)

    Diabetes: Dental Tips For more copies contact: National Institute of Dental and Craniofacial Research National Oral Health Information Clearinghouse ... damage the gum and bone that hold your teeth in place and may lead to painful chewing ...

  14. Incontinence Treatment: Dietary Tips

    Science.gov (United States)

    ... helpful, please consider supporting IFFGD with a small tax-deductible donation. Lifestyle Changes Dietary Tips Medication Bowel ... arises requiring an expert’s care. © Copyright 1998-2018 International Foundation for Functional Gastrointestinal Disorders, Inc. (IFFGD). All ...

  15. Benefits of rotational ground motions for planetary seismology

    Science.gov (United States)

    Donner, S.; Joshi, R.; Hadziioannou, C.; Nunn, C.; van Driel, M.; Schmelzbach, C.; Wassermann, J. M.; Igel, H.

    2017-12-01

    Exploring the internal structure of planetary objects is fundamental to understand the evolution of our solar system. In contrast to Earth, planetary seismology is hampered by the limited number of stations available, often just a single one. Classic seismology is based on the measurement of three components of translational ground motion. Its methods are mainly developed for a larger number of available stations. Therefore, the application of classical seismological methods to other planets is very limited. Here, we show that the additional measurement of three components of rotational ground motion could substantially improve the situation. From sparse or single station networks measuring translational and rotational ground motions it is possible to obtain additional information on structure and source. This includes direct information on local subsurface seismic velocities, separation of seismic phases, propagation direction of seismic energy, crustal scattering properties, as well as moment tensor source parameters for regional sources. The potential of this methodology will be highlighted through synthetic forward and inverse modeling experiments.

  16. ObsPy: A Python Toolbox for Seismology

    Science.gov (United States)

    Krischer, Lion; Megies, Tobias; Sales de Andrade, Elliott; Barsch, Robert; MacCarthy, Jonathan

    2017-04-01

    In recent years the Python ecosystem evolved into one of the most powerful and productive scientific environments across disciplines. ObsPy (https://www.obspy.org) is a fully community-driven, open-source project dedicated to providing a bridge for seismology into that ecosystem. It does so by offering Read and write support for essentially every commonly used data format in seismology with a unified interface and automatic format detection. This includes waveform data (MiniSEED, SAC, SEG-Y, Reftek, …) as well as station (SEED, StationXML, …) and event meta information (QuakeML, ZMAP, …). Integrated access to the largest data centers, web services, and real-time data streams (FDSNWS, ArcLink, SeedLink, ...). A powerful signal processing toolbox tuned to the specific needs of seismologists. Utility functionality like travel time calculations with the TauP method, geodetic functions, and data visualizations. ObsPy has been in constant development for more than seven years and is developed and used by scientists around the world with successful applications in all branches of seismology. Additionally it nowadays serves as the foundation for a large number of more specialized packages. This presentation will give a short overview of the capabilities of ObsPy and point out several representative or new use cases. Additionally we will discuss the road ahead as well as the long-term sustainability of open-source scientific software.

  17. Trends and opportunities in seismology. [Asilomar, California, January 3--9, 1976

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    Thirty-five experts in the fields of geology, geophysics, and engineering, from academia, government, and industry, were invited to participate in a workshop and address the many problems of national and global concern that require seismological expertise for their solutions. This report reviews the history, accomplishments, and status of seismology; assesses changing trends in seismological research and applications; and recommends future directions in the light of these changes and of the growing needs of society in areas in which seismology can make significant contributions. The first part of the volume discusses areas of opportunity (understanding earthquakes and reducing their hazards; exploration, energy, and resources; understanding the earth and planets) and realizing the benefits (the roles of Federal, state, and local governments, industry, and universities). The second part, Background and Progress, briefly considers each of the following topics: the birth and early growth of seismology, nuclear test monitoring and its scientific ramifications, instrumentation and data processing, geodynamics and plate tectonics, theoretical seismology, structure and composition of the earth, exploration seismology, seismic exploration for minerals, earthquake source mechanism studies, engineering seismology, strong ground motion and related earthquake hazards, volcanoes, tsunamis, planetary seismology, and international aspects of seismology. 26 figures. (RWR)

  18. Chlamydia - CDC Fact Sheet

    Science.gov (United States)

    ... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... sheet Pelvic Inflammatory Disease (PID) – CDC fact sheet Gonorrhea – CDC fact sheet STDs Home Page Bacterial Vaginosis ( ...

  19. CSC Tip Sheets: Community-Based Social Marketing

    Science.gov (United States)

    Use community-based social marketing (CBSM) to facilitate direct neighbor-to-neighbor communication and influence to promote behavior change. In-person communications are often complemented by electronic social media tools.

  20. Large earthquake rates from geologic, geodetic, and seismological perspectives

    Science.gov (United States)

    Jackson, D. D.

    2017-12-01

    Earthquake rate and recurrence information comes primarily from geology, geodesy, and seismology. Geology gives the longest temporal perspective, but it reveals only surface deformation, relatable to earthquakes only with many assumptions. Geodesy is also limited to surface observations, but it detects evidence of the processes leading to earthquakes, again subject to important assumptions. Seismology reveals actual earthquakes, but its history is too short to capture important properties of very large ones. Unfortunately, the ranges of these observation types barely overlap, so that integrating them into a consistent picture adequate to infer future prospects requires a great deal of trust. Perhaps the most important boundary is the temporal one at the beginning of the instrumental seismic era, about a century ago. We have virtually no seismological or geodetic information on large earthquakes before then, and little geological information after. Virtually all-modern forecasts of large earthquakes assume some form of equivalence between tectonic- and seismic moment rates as functions of location, time, and magnitude threshold. That assumption links geology, geodesy, and seismology, but it invokes a host of other assumptions and incurs very significant uncertainties. Questions include temporal behavior of seismic and tectonic moment rates; shape of the earthquake magnitude distribution; upper magnitude limit; scaling between rupture length, width, and displacement; depth dependence of stress coupling; value of crustal rigidity; and relation between faults at depth and their surface fault traces, to name just a few. In this report I'll estimate the quantitative implications for estimating large earthquake rate. Global studies like the GEAR1 project suggest that surface deformation from geology and geodesy best show the geography of very large, rare earthquakes in the long term, while seismological observations of small earthquakes best forecasts moderate earthquakes

  1. GASN sheets

    International Nuclear Information System (INIS)

    2013-12-01

    This document gathers around 50 detailed sheets which describe and present various aspects, data and information related to the nuclear sector or, more generally to energy. The following items are addressed: natural and artificial radioactive environment, evolution of energy needs in the world, radioactive wastes, which energy for France tomorrow, the consequences in France of the Chernobyl accident, ammunitions containing depleted uranium, processing and recycling of used nuclear fuel, transport of radioactive materials, seismic risk for the basic nuclear installations, radon, the precautionary principle, the issue of low doses, the EPR, the greenhouse effect, the Oklo nuclear reactors, ITER on the way towards fusion reactors, simulation and nuclear deterrence, crisis management in the nuclear field, does nuclear research put a break on the development of renewable energies by monopolizing funding, nuclear safety and security, the plutonium, generation IV reactors, comparison of different modes of electricity production, medical exposure to ionizing radiations, the control of nuclear activities, food preservation by ionization, photovoltaic solar collectors, the Polonium 210, the dismantling of nuclear installations, wind energy, desalination and nuclear reactors, from non-communication to transparency about nuclear safety, the Jules Horowitz reactor, CO 2 capture and storage, hydrogen, solar energy, the radium, the subcontractors of maintenance of the nuclear fleet, biomass, internal radio-contamination, epidemiological studies, submarine nuclear propulsion, sea energy, the Three Mile Island accident, the Chernobyl accident, the Fukushima accident, the nuclear after Fukushima

  2. Sustainable access to data, products, services and software from the European seismological Research Infrastructures: the EPOS TCS Seismology

    Science.gov (United States)

    Haslinger, Florian; Dupont, Aurelien; Michelini, Alberto; Rietbrock, Andreas; Sleeman, Reinoud; Wiemer, Stefan; Basili, Roberto; Bossu, Rémy; Cakti, Eser; Cotton, Fabrice; Crawford, Wayne; Diaz, Jordi; Garth, Tom; Locati, Mario; Luzi, Lucia; Pinho, Rui; Pitilakis, Kyriazis; Strollo, Angelo

    2016-04-01

    Easy, efficient and comprehensive access to data, data products, scientific services and scientific software is a key ingredient in enabling research at the frontiers of science. Organizing this access across the European Research Infrastructures in the field of seismology, so that it best serves user needs, takes advantage of state-of-the-art ICT solutions, provides cross-domain interoperability, and is organizationally and financially sustainable in the long term, is the core challenge of the implementation phase of the Thematic Core Service (TCS) Seismology within the EPOS-IP project. Building upon the existing European-level infrastructures ORFEUS for seismological waveforms, EMSC for seismological products, and EFEHR for seismological hazard and risk information, and implementing a pilot Computational Earth Science service starting from the results of the VERCE project, the work within the EPOS-IP project focuses on improving and extending the existing services, aligning them with global developments, to at the end produce a well coordinated framework that is technically, organizationally, and financially integrated with the EPOS architecture. This framework needs to respect the roles and responsibilities of the underlying national research infrastructures that are the data owners and main providers of data and products, and allow for active input and feedback from the (scientific) user community. At the same time, it needs to remain flexible enough to cope with unavoidable challenges in the availability of resources and dynamics of contributors. The technical work during the next years is organized in four areas: - constructing the next generation software architecture for the European Integrated (waveform) Data Archive EIDA, developing advanced metadata and station information services, fully integrate strong motion waveforms and derived parametric engineering-domain data, and advancing the integration of mobile (temporary) networks and OBS deployments in

  3. Magnet pole tips

    Science.gov (United States)

    Thorn, Craig E.; Chasman, Chellis; Baltz, Anthony J.

    1984-04-24

    An improved magnet which more easily provides a radially increasing magnetic field, as well as reduced fringe field and requires less power for a given field intensity. The subject invention comprises a pair of spaced, opposed magnetic poles which further comprise a pair of pole roots, each having a pole tip attached to its center. The pole tips define the gap between the magnetic poles and at least a portion of each pole tip is separated from its associated pole root. The separation begins at a predetermined distance from the center of the pole root and increases with increasing radial distance while being constant with azimuth within that portion. Magnets in accordance with the subject invention have been found to be particularly advantageous for use in large isochronous cyclotrons.

  4. Improved flare tip design

    Energy Technology Data Exchange (ETDEWEB)

    Gogolek, P. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

    2004-07-01

    This paper discusses the testing procedures and development of an improved flare tip design. Design objectives included performance equal to or better than utility flares at low wind speed; conversion efficiency; fuel slip; smoking; significant improvement at high wind speed; and no increase in trace emissions. A description of the testing facility of the flare tip was provided, with reference to the fact that the facility allowed for realistic near full scale gas flares in a single-pass flare test facility. Other details of the facility included: an adjustable ceiling; high capacity variable speed fan; sampling ports along working section in stack; windows along working section; and air cooled walls, floor, and ceiling. The fuels used in the flare tip included natural gas, propane, gasoline and inert gases. Details of wind speed, appurtenances and turbulence generating grids were presented, with reference to continuous gas emission measurements. A list of design constraints was provided. Flare performance included wind speed, turbulence and fuel composition. A chart of conversion inefficiencies with a correlation of wind speed and turbulence, fuel flow and pipe size was also presented. Several new tip designs were fabricated for testing, with screening tests for comparison to basic pipe and ranking designs. Significant improvements were found in one of the new designs, including results with 30 per cent propane in fuel. Emissions reduction from 10 to 35 per cent were noted. It was concluded that future work should focus on evaluating improved tip for stability at low wind speeds. Fuel slips are the primary source of emissions, and it was recommended that further research is necessary to improve existing flare tips. tabs, figs.

  5. Productivity tips for developers

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    I like to read about productivity tools and techniques, but the problem is - most of them are completely overrated, the tips are not that useful or they are too difficult to implement. But, sometimes I can find some stuff that really makes me think "damn, how could I live without this before?!". Today, I would like to share some of them and hopefully hear about the tips and tricks that you use. Maybe we can find a way to share them somehow (github repo/forum)?

  6. Bringing Seismology's Grand Challenges to the Undergraduate Classroom

    Science.gov (United States)

    Benoit, M. H.; Taber, J.; Hubenthal, M.

    2011-12-01

    The "Seismological Grand Challenges in Understanding Earth's Dynamic Systems," a community-written long-range science plan for the next decade, poses 10 questions to guide fundamental seismological research. Written in an approachable fashion suitable for policymakers, the broad questions and supporting discussion contained in this document offer an ideal framework for the development of undergraduate curricular materials. Leveraging this document, we have created a collection of inquiry-based classroom modules that utilize authentic data to modernize seismological instruction in 100 and 200 level undergraduate courses. The modules not only introduce undergraduates to the broad questions that the seismological community seeks to answer in the future but also showcase the numerous areas where modern seismological research is actively contributing to our understanding of fundamental Earth processes. To date 6 in-depth explorations that correspond to the Grand Challenges document have been developed. The specific topics for each exploration were selected to showcase modern seismological research while also covering topics commonly included in the curriculum of these introductory classes. Examples of activities that have been created and their corresponding Grand Challenge include: -A guided inquiry that introduces students to episodic tremor and slip and compares the GPS and seismic signatures of ETS with those produced from standard tectonic earthquakes (Grand Challenge "How do faults slip?"). - A laboratory exercise where students engage in b-value mapping of volcanic earthquakes to assess potential eruption hazards (How do magmas ascend and erupt?). - A module that introduce students to glacial earthquakes in Greenland and compares their frequency and spatial distribution to tectonic earthquakes (How do processes in the ocean and atmosphere interact with the solid Earth?). What is the relationship between stress and strain in the lithosphere? - An activity that

  7. Thirty Years of Innovation in Seismology with the IRIS Consortium

    Science.gov (United States)

    Sumy, D. F.; Woodward, R.; Aderhold, K.; Ahern, T. K.; Anderson, K. R.; Busby, R.; Detrick, R. S.; Evers, B.; Frassetto, A.; Hafner, K.; Simpson, D. W.; Sweet, J. R.; Taber, J.

    2015-12-01

    The United States academic seismology community, through the National Science Foundation (NSF)-funded Incorporated Research Institutions for Seismology (IRIS) Consortium, has promoted and encouraged a rich environment of innovation and experimentation in areas such as seismic instrumentation, data processing and analysis, teaching and curriculum development, and academic science. As the science continually evolves, IRIS helps drive the market for new research tools that enable science by establishing a variety of standards and goals. This has often involved working directly with manufacturers to better define the technology required, co-funding key development work or early production prototypes, and purchasing initial production runs. IRIS activities have helped establish de-facto international standards and impacted the commercial sector in areas such as seismic instrumentation, open-access data management, and professional development. Key institutional practices, conducted and refined over IRIS' thirty-year history of operations, have focused on open-access data availability, full retention of maximum-bandwidth, continuous data, and direct community access to state-of-the-art seismological instrumentation and software. These practices have helped to cultivate and support a thriving commercial ecosystem, and have been a key element in the professional development of multiple generations of seismologists who now work in both industry and academia. Looking toward the future, IRIS is increasing its engagement with industry to better enable bi-directional exchange of techniques and technology, and enhancing the development of tomorrow's workforce. In this presentation, we will illustrate how IRIS has promoted innovations grown out of the academic community and spurred technological advances in both academia and industry.

  8. Inge Lehmann’s work materials and seismological epistolary archive

    Directory of Open Access Journals (Sweden)

    Erik Hjortenberg

    2009-06-01

    Full Text Available

     

    The Inge Lehmann archive contains thousands of seismological work documents from Inge Lehmann’s private home. For a long time the author thought that the main concern was to keep the documents for posterity. There is now a renewed interest in Inge Lehmann, and some documents were presented in a poster at ESC Potsdam 2004, and the collection of documents were scanned and catalogued 2005-2006 at Storia Geofisica Ambiente in Bologna. Inge Lehmann (1888-1993 is famous for her discovery in 1936 of the earth’s inner core and for work on the upper mantle. A short biography is given. After her retirement in 1953 she worked at home in Denmark, and abroad in USA and in Canada. She took part in the creation of the European Seismological Commission in 1951, and in the creation of the International Seismological Centre in 1964. Inge Lehmann received many awards. Some letters from her early correspondence with Harold Jeffreys are discussed, they show how the inner core was discussed already in 1932. A few of the author’s reminiscences of Inge Lehmann are given.


  9. SEIS-PROV: Practical Provenance for Seismological Data

    Science.gov (United States)

    Krischer, L.; Smith, J. A.; Tromp, J.

    2015-12-01

    It is widely recognized that reproducibility is crucial to advance science, but at the same time it is very hard to actually achieve. This results in it being recognized but also mostly ignored by a large fraction of the community. A key ingredient towards full reproducibility is to capture and describe the history of data, an issue known as provenance. We present SEIS-PROV, a practical format and data model to store provenance information for seismological data. In a seismological context, provenance can be seen as information about the processes that generated and modified a particular piece of data. For synthetic waveforms the provenance information describes which solver and settings therein were used to generate it. When looking at processed seismograms, the provenance conveys information about the different time series analysis steps that led to it. Additional uses include the description of derived data types, such as cross-correlations and adjoint sources, enabling their proper storage and exchange. SEIS-PROV is based on W3C PROV (http://www.w3.org/TR/prov-overview/), a standard for generic provenance information. It then applies an additional set of constraints to make it suitable for seismology. We present a definition of the SEIS-PROV format, a way to check if any given file is a valid SEIS-PROV document, and two sample implementations: One in SPECFEM3D GLOBE (https://geodynamics.org/cig/software/specfem3d_globe/) to store the provenance information of synthetic seismograms and another one as part of the ObsPy (http://obspy.org) framework enabling automatic tracking of provenance information during a series of analysis and transformation stages. This, along with tools to visualize and interpret provenance graphs, offers a description of data history that can be readily tracked, stored, and exchanged.

  10. A Look at the Future of Controlled-Source Seismology

    Science.gov (United States)

    Keller, G. R.; Klemperer, S.; Hole, J.; Snelson, C.

    2008-12-01

    Facilities like EarthScope and IRIS/PASSCAL offer a framework in which to re-assess the role of our highest- resolution geophysical tool, controlled-source seismology. This tool is effective in near surface studies that focus on the upper 100 m of the crust to studies that focus on Moho structure and the lithospheric mantle. IRIS has now existed for over two decades and has transformed the way in which passive-source seismology in particular is carried out. Progress over these two decades has led to major discoveries about continental architecture and evolution through the development of three-dimensional images of the upper mantle and lithosphere. Simultaneously the hydrocarbon exploration industry has mapped increasingly large fractions of our sedimentary basins in three-dimensions and at unprecedented resolution and fidelity. Thanks to the additional instruments in the EarthScope facility, a clear scientific need and opportunity exists to map, at similar resolution, all of the crust - the igneous/metamorphic basement, the non-petroliferous basins that contain the record of continental evolution, and the seismogenic faults and active volcanoes that are the principal natural hazards we face. Controlled-source seismology remains the fundamental technology behind exploration for all fossil fuels and many water resources, and as such is a multi-billion-dollar industry centered in the USA. Academic scientists are leaders in developing the algorithms to process the most advanced industry data, but lack the academic data sets to which to apply this technology. University and government controlled-source seismologists, and their students who will populate the exploration industry, are increasingly divorced from that industry by their reliance on sparse spatial recording of usually only a single-component of the wavefield, generated by even sparser seismic sources. However, if we can find the resources, the technology now exists to provide seismic images of immense

  11. Coronal seismology waves and oscillations in stellar coronae

    CERN Document Server

    Stepanov, Alexander; Nakariakov, Valery M

    2012-01-01

    This concise and systematic account of the current state of this new branch of astrophysics presents the theoretical foundations of plasma astrophysics, magneto-hydrodynamics and coronal magnetic structures, taking into account the full range of available observation techniques -- from radio to gamma. The book discusses stellar loops during flare energy releases, MHD waves and oscillations, plasma instabilities and heating and charged particle acceleration. Current trends and developments in MHD seismology of solar and stellar coronal plasma systems are also covered, while recent p

  12. The experimental operation of a seismological data centre at Blacknest

    International Nuclear Information System (INIS)

    Grover, F.H.

    1978-10-01

    A short account is given of the development and operation of a unit within Blacknest which acts as a centre for handling data received from overseas seismological array stations and stations in the British Isles and also exchanges data with other centres. The work has been carried out as a long-term experiment to assess the capability of small networks of existing research and development stations to participate in the monitoring of a possible future Comprehensive Test Ban treaty (CTB) and to gain experience of the operational requirements for Data Centres. A preliminary assessment of a UK National Technical Means (NTM) for verifying a CTB is obtained inter alia. (author)

  13. Sports Dehydration Safety Tips

    Science.gov (United States)

    Sports Dehydration Safety Tips Everything you need to know to keep your kids safe from dehydration when playing sports. To keep kids in top ... to stay hydrated by drinking plenty of fluids. Dehydration occurs when a body loses more water than ...

  14. Evaluating Potential Tipping Points of Antarctic basins

    Science.gov (United States)

    Durand, G.; Sainan, S.; Pattyn, F.; Jourdain, N.

    2017-12-01

    Antarctica is currently loosing mass and its forthcoming contribution to sea-level rise could substantially increase during the coming centuries. This is essentially due to geometrical constraints, i.e., in regions where grounded ice lies on a bedrock below sea-level sloping down towards the interior of the ice sheet (retrograde slope). For such a configuration the ice sheet is considered potentially unstable, as suggested by theory. However, recent observations on accelerated grounding-line retreat and new insights in modeling Pine Island and Thwaites glaciers give evidence that such self-sustained retreat, called marine ice sheet instability (MISI), has already been on its way. Although West Antarctica appears to be the most vulnerable region for MISI occurrence, similar topographic configurations are also observed in East Antarctica, in the Wilkes Basin in particular. Therefore, evaluating the MISI potential at a pan-Antarctic scale is becoming a priority. Here, using the f.ETISh ice sheet model, an ensemble of simulations of the entire contemporary Antarctic ice sheet has been carried out. In particular, we investigate the debuttressing of ice shelves required to initiate MISI for each coastal region around Antarctica by forcing the model with realistic sub-shelf melt pulses of varying duration and amplitude. We further identify the currently grounded areas where the outlet glaciers could hardly stabilize, the Amundsen Sea Sector being the more prone to large self-sustained retreats. On the contrary, the ability of Cook and Ninnis ice shelves to recover after large perturbations and enough buttress upstream outlet glaciers tends to limit self-sustained retreat of the sector. For each basin, rates of contribution to sea-level rise are discussed together with the RCPs and time when tipping points could be reached and MISI triggered.

  15. Towards monitoring the englacial fracture state using virtual-reflector seismology

    Science.gov (United States)

    Lindner, F.; Weemstra, C.; Walter, F.; Hadziioannou, C.

    2018-04-01

    In seismology, coda wave interferometry (CWI) is an effective tool to monitor time-lapse changes using later arriving, multiply scattered coda waves. Typically, CWI relies on an estimate of the medium's impulse response. The latter is retrieved through simple time-averaging of receiver-receiver cross-correlations of the ambient field, i.e. seismic interferometry (SI). In general, the coda are induced by heterogeneities in the Earth. Being comparatively homogeneous, however, ice bodies such as glaciers and ice sheets exhibit little scattering. In addition, the temporal stability of the time-averaged cross-correlations suffers from temporal variations in the distribution and amplitude of the passive seismic sources. Consequently, application of CWI to ice bodies is currently limited. Nevertheless, fracturing and changes in the englacial macroscopic water content alter the bulk elastic properties of ice bodies, which can be monitored with cryoseismological measurements. To overcome the current limited applicability of CWI to ice bodies, we therefore introduce virtual-reflector seismology (VRS). VRS relies on a so-called multidimensional deconvolution (MDD) process of the time-averaged crosscorrelations. The technique results in the retrieval of a medium response that includes virtual reflections from a contour of receivers enclosing the region of interest (i.e., the region to be monitored). The virtual reflections can be interpreted as artificial coda replacing the (lacking) natural scattered coda. Hence, this artificial coda might be exploited for the purpose of CWI. From an implementation point of view, VRS is similar to SI by MDD, which, as its name suggests, also relies on a multidimensional deconvolution process. SI by MDD, however, does not generate additional virtual reflections. Advantageously, both techniques mitigate spurious coda changes associated with temporal variations in the distribution and amplitude of the passive seismic sources. In this work, we

  16. Using Cascading Style Sheets to Design a Fly-Out Menu with Microsoft Visual Studio

    Science.gov (United States)

    Liu, Chang; Downing, Charles

    2010-01-01

    The menu has become an integrated component within nearly all professionally designed websites. This teaching tip presents a no-code way to design either a vertical or a horizontal fly-out menu by using Cascading Style Sheets (CSS) within Microsoft Visual Studio 2008. The approach described in this tip helps students fully understand how to…

  17. seismo-live: Training in Seismology using Jupyter Notebooks

    Science.gov (United States)

    Igel, Heiner; Krischer, Lion; van Driel, Martin; Tape, Carl

    2017-04-01

    Practical training in computational methodologies is still underrepresented in Earth science curriculae despite the increasing use of sometimes highly sophisticated simulation and data processing technologies in research projects. At the same time well-engineered community codes make it easy to return results yet with the danger that the inherent traps of black-box solutions are not well understood. For this purpose we have initiated a community platform (www.seismo-live.org) where Python-based Jupyter notebooks can be accessed and run without necessary downloads or local software installations. The increasingly popular Jupyter notebooks allow combining markup language, graphics, equations, with interactive, executable python codes. The platform already includes general Python training, introduction to the ObsPy library for seismology as well as seismic data processing, noise analysis, and a variety of forward solvers for seismic wave propagation. In addition, an example is shown how Jupyter notebooks can be used to increase reproducibility of published results. Submission of Jupyter notebooks for general seismology are encouraged. The platform can be used for complementary teaching in Earth Science courses on compute-intensive research areas. We present recent developments and new features.

  18. seismo-live: Training in Computational Seismology using Jupyter Notebooks

    Science.gov (United States)

    Igel, H.; Krischer, L.; van Driel, M.; Tape, C.

    2016-12-01

    Practical training in computational methodologies is still underrepresented in Earth science curriculae despite the increasing use of sometimes highly sophisticated simulation technologies in research projects. At the same time well-engineered community codes make it easy to return simulation-based results yet with the danger that the inherent traps of numerical solutions are not well understood. It is our belief that training with highly simplified numerical solutions (here to the equations describing elastic wave propagation) with carefully chosen elementary ingredients of simulation technologies (e.g., finite-differencing, function interpolation, spectral derivatives, numerical integration) could substantially improve this situation. For this purpose we have initiated a community platform (www.seismo-live.org) where Python-based Jupyter notebooks can be accessed and run without and necessary downloads or local software installations. The increasingly popular Jupyter notebooks allow combining markup language, graphics, equations with interactive, executable python codes. We demonstrate the potential with training notebooks for the finite-difference method, pseudospectral methods, finite/spectral element methods, the finite-volume and the discontinuous Galerkin method. The platform already includes general Python training, introduction to the ObsPy library for seismology as well as seismic data processing and noise analysis. Submission of Jupyter notebooks for general seismology are encouraged. The platform can be used for complementary teaching in Earth Science courses on compute-intensive research areas.

  19. Seismologically determined bedload flux during the typhoon season.

    Science.gov (United States)

    Chao, Wei-An; Wu, Yih-Min; Zhao, Li; Tsai, Victor C; Chen, Chi-Hsuan

    2015-02-05

    Continuous seismic records near river channels can be used to quantify the energy induced by river sediment transport. During the 2011 typhoon season, we deployed a seismic array along the Chishan River in the mountain area of southern Taiwan, where there is strong variability in water discharge and high sedimentation rates. We observe hysteresis in the high-frequency (5-15 Hz) seismic noise level relative to the associated hydrological parameters. In addition, our seismic noise analysis reveals an asymmetry and a high coherence in noise cross-correlation functions for several station pairs during the typhoon passage, which corresponds to sediment particles and turbulent flows impacting along the riverbed where the river bends sharply. Based on spectral characteristics of the seismic records, we also detected 20 landslide/debris flow events, which we use to estimate the sediment supply. Comparison of sediment flux between seismologically determined bedload and derived suspended load indicates temporal changes in the sediment flux ratio, which imply a complex transition process from the bedload regime to the suspension regime between typhoon passage and off-typhoon periods. Our study demonstrates the possibility of seismologically monitoring river bedload transport, thus providing valuable additional information for studying fluvial bedrock erosion and mountain landscape evolution.

  20. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... or bypass, without the risks that accompany open surgery. TIPS is a minimally invasive procedure that typically has a shorter recovery time than surgery. Your TIPS should have less of an effect ...

  1. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... then placed in this tunnel to keep the pathway open. Patients who typically need a TIPS have ... and stomach. A TIPS procedure involves creating a pathway through the liver that connects the portal vein ( ...

  2. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... and/or hydrothorax (in the chest). Budd-Chiari syndrome , a blockage in one or more veins that ... intentionally to solve the problem. Although extremely rare, children may also require a TIPS procedure. TIPS in ...

  3. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... filtered out by the liver. The TIPS may cause too much of these substances to bypass the ...

  4. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the esophagus and stomach. A TIPS procedure involves creating a pathway through the liver that connects the ... diseases. This can result in significant challenges in creating the TIPS. top of page Additional Information and ...

  5. Tips for Living with Scleroderma

    Science.gov (United States)

    ... Patients Tips for Living Tips for Living with Scleroderma Ways to help manage your symptoms The Scleroderma ... help find improved therapies and a cure for scleroderma! Your gift today will be matched to have ...

  6. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... TIPS. top of page What are some common uses of the procedure? A TIPS is used to ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  7. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... recovery time than surgery. Your TIPS should have less of an effect than open surgical bypass on ...

  8. 10 CFR 72.102 - Geological and seismological characteristics for applications before October 16, 2003 and...

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Geological and seismological characteristics for... WASTE Siting Evaluation Factors § 72.102 Geological and seismological characteristics for applications..., sites will be acceptable if the results from onsite foundation and geological investigation, literature...

  9. Characterization of metal-coated fiber tip for NSOM lithography by tip-to-tip scan

    International Nuclear Information System (INIS)

    Kubicova, I.; Pudis, D.; Suslik, L.; Skriniarova, J.

    2011-01-01

    For the optical field characterization, a tip-to-tip scan of two metal-coated fiber tips with circular aperture at the apex was performed. The optical field irradiated from the fiber probe in illumination mode was analyzed by NSOM represented by fiber probe in collection mode. The near-field intensity profile of the source fiber tip in the plane perpendicular to the axis of the tip was taken. Experimental stage requires high resolution 3D motion system controlled by computer (Fig. 1). The source and the detector fiber tip were placed on the moving and static part of the 3D nanoposition system, respectively. As a light source, a modulated 473 nm DPSS laser was used. After the source fiber tip characterization, the NSOM lithography was performed. In the experimental setup from Fig. 1, the detector fiber tip was replaced by a sample fixed in a vacuum holder. As a sample, a 600 nm positive photoresist AZ 5214E was spin-coated on a GaAs substrate. Exposure was carried out by irradiation of the sample at desired positions through the fiber tip aperture. The sample was developed in AZ 400K developer for 30 s and rinsed in DI water. A promising tip-to-tip scanning technique for characterization of metal-coated fiber tips with aperture at the apex was presented. Nearly-circular aperture shapes were documented from NSOM measurements with diameter estimated to be less than 460 nm. By knowing the source-detector distance and the FWHM of the near-field intensity profile, the tip-to-tip scan proves an easy and fast method to analyze the fiber tip aperture properties. The fiber tip resolution was confirmed by preparation of 2D planar structures in thin photoresist layer, where the NSOM lithography uses the metal-coated fiber tip characterized in previous section. (authors)

  10. TIPS Pamphlets for Parents.

    Science.gov (United States)

    Algozzine, Bob, Ed.; Ysseldyke, Jim, Ed.

    This manual presents 99 one-sheet informational brochures designed to improve parenting skills for children with and without disabilities. Each brochure is in a format suitable for duplicating, folding, and distributing. Each brochure offers references to related brochures in the collection. Brochures are grouped under the following broad areas:…

  11. New developments in high resolution borehole seismology and their applications to reservoir development and management

    Energy Technology Data Exchange (ETDEWEB)

    Paulsson, B.N.P. [Chevron Petroleum Technology Company, La Habra, CA (United States)

    1997-08-01

    Single-well seismology, Reverse Vertical Seismic Profiles (VSP`s) and Crosswell seismology are three new seismic techniques that we jointly refer to as borehole seismology. Borehole seismic techniques are of great interest because they can obtain much higher resolution images of oil and gas reservoirs than what is obtainable with currently used seismic techniques. The quality of oil and gas reservoir management decisions depend on the knowledge of both the large and the fine scale features in the reservoirs. Borehole seismology is capable of mapping reservoirs with an order of magnitude improvement in resolution compared with currently used technology. In borehole seismology we use a high frequency seismic source in an oil or gas well and record the signal in the same well, in other wells, or on the surface of the earth.

  12. Tip-modified Propellers

    DEFF Research Database (Denmark)

    Andersen, Poul

    1999-01-01

    The paper deals with tip-modified propellers and the methods which, over a period of two decades, have been applied to develop such propellers. The development is driven by the urge to increase the efficiency of propellers and can be seen as analogous to fitting end plates and winglets to aircraft...... propeller, have efficiency increases of a reasonable magnitude in both open-water and behind-ship conditions....

  13. Using a Web Site to Support a Seismology Course Textbook

    Science.gov (United States)

    Wysession, M. E.; Stein, S.

    2004-12-01

    We present a course in seismology that consists of a textbook with an accompanying web site (http://epscx.wustl.edu/seismology/book). The web site serves many different functions, and is of great importance as a companion to the curriculum in several different ways: (1) All of the more than 600 figures from the book are available on the web site. Geophysics is a very visually-oriented discipline, and many concepts are more easily taught with appropriate visual tools. In addition, many instructors are now using computer-based lecture programs such as PowerPoint. To aid in this, all of the figures are displayed in a common JPG format, both with and without titles. They are available to be used in a seismology course, or any kind of Earth Science course. This way, an instructor can easily grab a figure from the web site and drop it into a PowerPoint format. The figures are listed by number, but are also obtainable from menus of thumbnail sketches. If an instructor would like all of the figures, they can be obtained as large zip files, which can be unzipped after downloading. In addition, sample PowerPoint lectures using the figures as well the equations from the text will be available on the course web site. (2) Solutions to all of the homework problems are available in PDF format on the course website. Homework is a vital component of any quantitative course, but it is often a significant time commitment for instructors to derive all of the homework problems. In addition, it is much easier to select which homework problems are desired to be assigned if the solutions can be seen. The 64 pages of homework solutions are on a secure web site that requires a user ID and password that can be obtained from the authors. (3) Any errors found in the textbook are immediately posted on an "Errata" web page. Many of these errors are found by instructors who are using the curriculum (and they are given credit for finding the errors!). The text becomes an interactive process

  14. ObsPy - A Python Toolbox for Seismology - and Applications

    Science.gov (United States)

    Krischer, L.; Megies, T.; Barsch, R.; MacCarthy, J.; Lecocq, T.; Koymans, M. R.; Carothers, L.; Eulenfeld, T.; Reyes, C. G.; Falco, N.; Sales de Andrade, E.

    2017-12-01

    Recent years witnessed the evolution of Python's ecosystem into one of the most powerful and productive scientific environments across disciplines. ObsPy (https://www.obspy.org) is a fully community driven, open-source project dedicated to provide a bridge for seismology into that ecosystem. It is a Python toolbox offering: Read and write support for essentially every commonly used data format in seismology with a unified interface and automatic format detection. This includes waveform data (MiniSEED, SAC, SEG-Y, Reftek, …) as well as station (SEED, StationXML, SC3ML, …) and event meta information (QuakeML, ZMAP, …). Integrated access to the largest data centers, web services, and real-time data streams (FDSNWS, ArcLink, SeedLink, ...). A powerful signal processing toolbox tuned to the specific needs of seismologists. Utility functionality like travel time calculations with the TauP method, geodetic functions, and data visualizations. ObsPy has been in constant development for more than eight years and is developed and used by scientists around the world with successful applications in all branches of seismology. Additionally it nowadays serves as the foundation for a large number of more specialized packages. Newest features include: Full interoperability of SEED and StationXML/Inventory objects Access to the Nominal Response Library (NRL) for easy and quick creation of station metadata from scratch Support for the IRIS Federated Catalog Service Improved performance of the EarthWorm client Several improvements to MiniSEED read/write module Improved plotting capabilities for PPSD (spectrograms, PSD of discrete frequencies over time, ..) Support for.. Reading ArcLink Inventory XML Reading Reftek data format Writing SeisComp3 ML (SC3ML) Writing StationTXT format This presentation will give a short overview of the capabilities of ObsPy and point out several representative or new use cases and show-case some projects that are based on ObsPy, e.g.: seismo

  15. Solving some problems of engineering seismology by structural method

    International Nuclear Information System (INIS)

    Ishtev, K.G.; Hadjikov, L.M.; Dineva, P.S.; Jordanov, P.P.

    1983-01-01

    The work suggests a method for solving the direct and inverse problems of the engineer seismology by means of the structural approach of the systems theory. This approach gives a possibility for a simultaneous accounting of the two basic types of damping of the seismic signals in the earth foundation-geometrical damping and a damping in consequence of a dissipative energy loss. By the structural scheme an automatic account is made of the geometric damping of the signals. The damping from a dissipative energy loss on the other hand is accounted for through a choice of the type of frequency characteristics or the transmission functions of the different layers. With a few examples the advantages of the model including the two types of attenuation of the seismic signal are illustrated. An integral coefficient of damping is calculated which analogously to the frequency functions represents a generalized characteristic of is the whole earth foundation. (orig./HP)

  16. Can mobile phones used in strong motion seismology?

    Science.gov (United States)

    D'Alessandro, Antonino; D'Anna, Giuseppe

    2013-04-01

    Micro Electro-Mechanical Systems (MEMS) accelerometers are electromechanical devices able to measure static or dynamic accelerations. In the 1990s MEMS accelerometers revolutionized the automotive-airbag system industry and are currently widely used in laptops, game controllers and mobile phones. Nowadays MEMS accelerometers seems provide adequate sensitivity, noise level and dynamic range to be applicable to earthquake strong motion acquisition. The current use of 3 axes MEMS accelerometers in mobile phone maybe provide a new means to easy increase the number of observations when a strong earthquake occurs. However, before utilize the signals recorded by a mobile phone equipped with a 3 axes MEMS accelerometer for any scientific porpoise, it is fundamental to verify that the signal collected provide reliable records of ground motion. For this reason we have investigated the suitability of the iPhone 5 mobile phone (one of the most popular mobile phone in the world) for strong motion acquisition. It is provided by several MEMS devise like a three-axis gyroscope, a three-axis electronic compass and a the LIS331DLH three-axis accelerometer. The LIS331DLH sensor is a low-cost high performance three axes linear accelerometer, with 16 bit digital output, produced by STMicroelectronics Inc. We have tested the LIS331DLH MEMS accelerometer using a vibrating table and the EpiSensor FBA ES-T as reference sensor. In our experiments the reference sensor was rigidly co-mounted with the LIS331DHL MEMS sensor on the vibrating table. We assessment the MEMS accelerometer in the frequency range 0.2-20 Hz, typical range of interesting in strong motion seismology and earthquake engineering. We generate both constant and damped sine waves with central frequency starting from 0.2 Hz until 20 Hz with step of 0.2 Hz. For each frequency analyzed we generate sine waves with mean amplitude 50, 100, 200, 400, 800 and 1600 mg0. For damped sine waves we generate waveforms with initial amplitude

  17. AERODYNAMICS OF WING TIP SAILS

    Directory of Open Access Journals (Sweden)

    MUSHTAK AL-ATABI

    2006-06-01

    Full Text Available Observers have always been fascinated by soaring birds. An interesting feature of these birds is the existence of few feathers extending from the tip of the wing. In this paper, small lifting surfaces were fitted to the tip of a NACA0012 wing in a fashion similar to that of wing tip feathers. Experimental measurements of induced drag, longitudinal static stability and trailing vortex structure were obtained.The tests showed that adding wing tip surfaces (sails decreased the induced drag factor and increased the longitudinal static stability. Results identified two discrete appositely rotated tip vortices and showed the ability of wing tip surfaces to break them down and to diffuse them.

  18. Tips for Starting Physical Activity

    Science.gov (United States)

    ... Legislative Information Advisory & Coordinating Committees Strategic Plans & Reports Research Areas FAQs ... Starting Physical Activity Related Topics Section Navigation Tips to Help You Get Active ...

  19. Moving towards persistent identification in the seismological community

    Science.gov (United States)

    Quinteros, Javier; Evans, Peter; Strollo, Angelo; Ulbricht, Damian; Elger, Kirsten; Bertelmann, Roland

    2016-04-01

    The GEOFON data centre and others in the seismological community have been archiving seismic waveforms for many years. The amount of seismic data available continuously increases due to the use of higher sampling rates and the growing number of stations. In recent years, there is a trend towards standardization of the protocols and formats to improve and homogenise access to these data [FDSN, 2013]. The seismological community has begun assigning a particular persistent identifier (PID), the Digital Object Identifier (DOI), to seismic networks as a first step for properly and consistently attributing the use of data from seismic networks in scientific articles [Evans et al., 2015]. This was codified in a recommendation by the international Federation of Digital Seismic Networks [FDSN, 2014]; DOIs for networks now appear in community web pages. However, our community, in common with other fields of science, still struggles with issues such as: supporting reproducibility of results; providing proper attribution (data citation) for data sets; and measuring the impact (by tracking their use) of, those data sets. Seismological data sets used for research are frequently created "on-the-fly" based on particular user requirements such as location or time period; users prepare requests to select subsets of the data held in seismic networks; the data actually provided may even be held at many different data centres [EIDA, 2016]. These subsets also require careful citation. For persistency, a request must receive exactly the same data when repeated at a later time. However, if data are curated between requests, the data set delivered may differ, severely complicating the ability to reproduce a result. Transmission problems or configuration problems may also inadvertently modify the response to a request. With this in mind, our next step is the assignment of additional EPIC-PIDs to daily data files (currently over 28 million in the GEOFON archive) for use within the data

  20. Towards a single seismological service infrastructure in Europe

    Science.gov (United States)

    Spinuso, A.; Trani, L.; Frobert, L.; Van Eck, T.

    2012-04-01

    In the last five year services and data providers, within the seismological community in Europe, focused their efforts in migrating the way of opening their archives towards a Service Oriented Architecture (SOA). This process tries to follow pragmatically the technological trends and available solutions aiming at effectively improving all the data stewardship activities. These advancements are possible thanks to the cooperation and the follow-ups of several EC infrastructural projects that, by looking at general purpose techniques, combine their developments envisioning a multidisciplinary platform for the earth observation as the final common objective (EPOS, Earth Plate Observation System) One of the first results of this effort is the Earthquake Data Portal (http://www.seismicportal.eu), which provides a collection of tools to discover, visualize and access a variety of seismological data sets like seismic waveform, accelerometric data, earthquake catalogs and parameters. The Portal offers a cohesive distributed search environment, linking data search and access across multiple data providers through interactive web-services, map-based tools and diverse command-line clients. Our work continues under other EU FP7 projects. Here we will address initiatives in two of those projects. The NERA, (Network of European Research Infrastructures for Earthquake Risk Assessment and Mitigation) project will implement a Common Services Architecture based on OGC services APIs, in order to provide Resource-Oriented common interfaces across the data access and processing services. This will improve interoperability between tools and across projects, enabling the development of higher-level applications that can uniformly access the data and processing services of all participants. This effort will be conducted jointly with the VERCE project (Virtual Earthquake and Seismology Research Community for Europe). VERCE aims to enable seismologists to exploit the wealth of seismic data

  1. Creating a Facebook Page for the Seismological Society of America

    Science.gov (United States)

    Newman, S. B.

    2009-12-01

    In August, 2009 I created a Facebook “fan” page for the Seismological Society of America. We had been exploring cost-effective options for providing forums for two-way communication for some months. We knew that a number of larger technical societies had invested significant sums of money to create customized social networking sites but that a small society would need to use existing low-cost software options. The first thing I discovered when I began to set up the fan page was that an unofficial SSA Facebook group already existed, established by Steven J. Gibbons, a member in Norway. Steven had done an excellent job of posting material about SSA. Partly because of the existing group, the official SSA fan page gained fans rapidly. We began by posting information about our own activities and then added links to activities in the broader geoscience community. While much of this material also appeared on our website and in our publication, Seismological Research Letters (SRL), the tone on the FB page is different. It is less formal with more emphasis on photos and links to other sites, including our own. Fans who are active on FB see the posts as part of their social network and do not need to take the initiative to go to the SSA site. Although the goal was to provide a forum for two-way communication, our initial experience was that people were clearly reading the page but not contributing content. This appears to be case with fan pages of sister geoscience societies. FB offers some demographic information to fan site administrators. In an initial review of the demographics it appeared that fans were younger than the overall demographics of the Society. It appeared that a few of the fans are not members or even scientists. Open questions are: what content will be most useful to fans? How will the existence of the page benefit the membership as a whole? Will the page ultimately encourage two-way communication as hoped? Web 2.0 is generating a series of new

  2. Refining Southern California Geotherms Using Seismologic, Geologic, and Petrologic Constraints

    Science.gov (United States)

    Thatcher, W. R.; Chapman, D. S.; Allam, A. A.; Williams, C. F.

    2017-12-01

    Lithospheric deformation in tectonically active regions depends on the 3D distribution of rheology, which is in turn critically controlled by temperature. Under the auspices of the Southern California Earthquake Center (SCEC) we are developing a 3D Community Thermal Model (CTM) to constrain rheology and so better understand deformation processes within this complex but densely monitored and relatively well-understood region. The San Andreas transform system has sliced southern California into distinct blocks, each with characteristic lithologies, seismic velocities and thermal structures. Guided by the geometry of these blocks we use more than 250 surface heat-flow measurements to define 13 geographically distinct heat flow regions (HFRs). Model geotherms within each HFR are constrained by averages and variances of surface heat flow q0 and the 1D depth distribution of thermal conductivity (k) and radiogenic heat production (A), which are strongly dependent on rock type. Crustal lithologies are not always well known and we turn to seismic imaging for help. We interrogate the SCEC Community Velocity Model (CVM) to determine averages and variances of Vp, Vs and Vp/Vs versus depth within each HFR. We bound (A, k) versus depth by relying on empirical relations between seismic wave speed and rock type and laboratory and modeling methods relating (A, k) to rock type. Many 1D conductive geotherms for each HFR are allowed by the variances in surface heat flow and subsurface (A, k). An additional constraint on the lithosphere temperature field is provided by comparing lithosphere-asthenosphere boundary (LAB) depths identified seismologically with those defined thermally as the depth of onset of partial melting. Receiver function studies in Southern California indicate LAB depths that range from 40 km to 90 km. Shallow LAB depths are correlated with high surface heat flow and deep LAB with low heat flow. The much-restricted families of geotherms that intersect peridotite

  3. Regional geology, tectonic, geomorphology and seismology studies to interest to nuclear power plants at Itaorna beach

    International Nuclear Information System (INIS)

    Hasui, Y.; Almeida, F.F.M. de; Mioto, J.A.; Melo, M.S. de.

    1982-01-01

    The study prepared for the nuclear power plants to be located at Itaorna comprised, the analysis and integration of Geologic, tectonic, geomorphologic and seismologic information and satisfactory results of regional stability were obtained. (L.H.L.L.) [pt

  4. Recent research in earth structure, earthquake and mine seismology, and seismic hazard evaluation in South Africa

    CSIR Research Space (South Africa)

    Wright, C

    2003-07-01

    Full Text Available of earthquakes, earthquake hazard and earth structure in South Africa was prepared for the centennial handbook of the Interna- tional Association of Seismology and the Physics of the Earth?s Interior(IASPEI).3 Referencestothesescompletedinthelastfour...

  5. Mobile and modular. BGR develops seismological monitoring stations for universal applications

    International Nuclear Information System (INIS)

    Hinz, Erwin; Hanneken, Mark

    2016-01-01

    BGR seismologists often set up monitoring stations for testing purposes. The engineers from the Central Seismological Observatory have now developed a new type of mobile monitoring station which can be remotely controlled.

  6. QuakeML: status of the XML-based seismological data exchange format

    OpenAIRE

    Joachim Saul; Philipp Kästli; Fabian Euchner; Danijel Schorlemmer

    2011-01-01

    QuakeML is an XML-based data exchange standard for seismology that is in its fourth year of active community-driven development. Its development was motivated by the need to consolidate existing data formats for applications in statistical seismology, as well as setting a cutting-edge, community-agreed standard to foster interoperability of distributed infrastructures. The current release (version 1.2) is based on a public Request for Comments process and accounts for suggestions and comments...

  7. Urban Seismology: on the origin of earth vibrations within a city

    OpenAIRE

    Díaz, Jordi; Ruiz, Mario; Sánchez-Pastor, Pilar S.; Romero, Paula

    2017-01-01

    Urban seismology has become an active research field in the recent years, both with seismological objectives, as obtaining better microzonation maps in highly populated areas, and with engineering objectives, as the monitoring of traffic or the surveying of historical buildings. We analyze here the seismic records obtained by a broad-band seismic station installed in the ICTJA-CSIC institute, located near the center of Barcelona city. Although this station was installed to introdu...

  8. Research and development activities of the Seismology Section for the period January 1988-December 1989

    International Nuclear Information System (INIS)

    Kumar, Vijay; Murty, G.S.

    1990-01-01

    This report summarises the research and development activities of the Seismology Section during the periods from January 1988 to December 1989. Apart from the ongoing work on forensic seismology, seismicity studies, rock burst monitoring, elastic wave propagation, a new field system became operational at Bhatsa, located about 100 km from Bombay, comprising 11 station radio-telemetered seismic network with a central recording laboratory to study the reservoir induced seismicity. (author). figs., tabs

  9. State-of-the-art of the historical seismology in Colombia

    Directory of Open Access Journals (Sweden)

    E. J. Salcedo Hurtado

    2004-06-01

    Full Text Available In Colombia are available a discreet number of historical seismology investigations, dating back 50 years. This paper reviews basic information about earthquakes studies in Colombia, such as primary sources, compilation of descriptive catalogues and parametric catalogues. Father Jesús Emilio Ramírez made the main systematic study before 1975. During the last 20 years, great earthquakes hit Colombia and, as consequence, historical seismology investigation was developed in the frame of seismic hazard projects.

  10. Tips for Good Electronic Presentations.

    Science.gov (United States)

    Strasser, Dennis

    1996-01-01

    Describes library uses of presentation graphics software and offers tips for creating electronic presentations. Tips include: audience retention; visual aid options; software package options; presentation planning; presentation showing; and use of text, colors, and graphics. Sidebars note common presentation errors and popular presentation…

  11. Effects of magnitude, depth, and time on cellular seismology forecasts

    Science.gov (United States)

    Fisher, Steven Wolf

    This study finds that, in most cases analyzed to date, past seismicity tends to delineate zones where future earthquakes are likely to occur. Network seismicity catalogs for the New Madrid Seismic Zone (NMSZ), Australia (AUS), California (CA), and Alaska (AK) are analyzed using modified versions of the Cellular Seismology (CS) method of Kafka (2002, 2007). The percentage of later occurring earthquakes located near earlier occurring earthquakes typically exceeds the expected percentage for randomly distributed later occurring earthquakes, and the specific percentage is influenced by several variables, including magnitude, depth, time, and tectonic setting. At 33% map area coverage, hit percents are typically 85-95% in the NMSZ, 50-60% in AUS, 75-85% in CA, and 75-85% in AK. Statistical significance testing is performed on trials analyzing the same variables so that the overall regions can be compared, although some tests are inconclusive due to the small number of earthquake sample sizes. These results offer useful insights into understanding the capabilities and limits of CS studies, which can provide guidance for improving the seismicity-based components of seismic hazard assessments.

  12. Ambient seismic noise tomography for exploration seismology at Valhall

    Science.gov (United States)

    de Ridder, S. A.

    2011-12-01

    Permanent ocean-bottom cables installed at the Valhall field can repeatedly record high quality active seismic surveys. But in the absence of active seismic shooting, passive data can be recorded and streamed to the platform in real time. Here I studied 29 hours of data using seismic interferometry. I generate omni-directional Scholte-wave virtual-sources at frequencies considered very-low in the exploration seismology community (0.4-1.75 Hz). Scholte-wave group arrival times are inverted using both eikonal tomography and straight-ray tomography. The top 100 m near-surface at Valhall contains buried channels about 100 m wide that have been imaged with active seismic. Images obtained by ASNT using eikonal tomography or straight-ray tomography both contain anomalies that match these channels. When continuous recordings are made in real-time, tomography images of the shallow subsurface can be formed or updated on a daily basis, forming a very low cost near-surface monitoring system using seismic noise.

  13. Jovian seismology: preliminary results of the SYMPA instrument

    Science.gov (United States)

    Gaulme, P.; Schmider, F. X.; Gay, J.; Jacob, C.; Jeanneaux, F.; Alvarez, M.; Reyes, M.; Valtier, J. C.; Fossat, E.; Palle, P. L.; Belmonte, J. C.; Gelly, B.

    2006-06-01

    Jupiter's internal structure is poorly known (Guillot et al. 2004). Seismology is a powerful tool to investigate the internal structure of planets and stars, by analyzing how acoustic waves propagate. Mosser (1997) and Gudkova & Zarkhov (1999) showed that the detection and the identification of non-radial modes up to degree ℓ=25 can constrain strongly the internal structure. SYMPA is a ground-based network project dedicated to the Jovian oscillations (Schmider et al. 2002). The instrument is composed of a Mach-Zehnder interferometer producing four interferograms of the planetary spectrum. The combination of the four images in phase quadrature allows the reconstruction of the incident light phase, which is related to the Doppler shift generated by the oscillations. Two SYMPA instruments were built at the Nice university and were used simultaneously during two observation campaigns, in 2004 and 2005, at the San Pedro Martir observatory (Mexico) and the Teide observatory (Las Canarias). We will present for the first time the data processing and the preliminary results of the experiment.

  14. Waves and rays in seismology answers to unasked questions

    CERN Document Server

    Slawinski, Michael A

    2016-01-01

    The author dedicates this book to readers who are concerned with finding out the status of concepts, statements and hypotheses, and with clarifying and rearranging them in a logical order. It is thus not intended to teach tools and techniques of the trade, but to discuss the foundations on which seismology — and in a larger sense, the theory of wave propagation in solids — is built. A key question is: why and to what degree can a theory developed for an elastic continuum be used to investigate the propagation of waves in the Earth, which is neither a continuum nor fully elastic. But the scrutiny of the foundations goes much deeper: material symmetry, effective tensors, equivalent media; the influence (or, rather, the lack thereof) of gravitational and thermal effects and the rotation of the Earth, are discussed ab initio. The variational principles of Fermat and Hamilton and their consequences for the propagation of elastic waves, causality, Noether's theorem and its consequences on conservation of energy...

  15. Simulated Nano scale Peeling Process of Monolayer Graphene Sheet: Effect of Edge Structure and Lifting Position

    International Nuclear Information System (INIS)

    Sasaki, N.; Okamoto, H.; Masuda, S.; Itamura, N.; Miura, K.

    2010-01-01

    The nanoscale peeling of the graphene sheet on the graphite surface is numerically studied by molecular mechanics simulation. For center-lifting case, the successive partial peelings of the graphene around the lifting center appear as discrete jumps in the force curve, which induce the arched deformation of the graphene sheet. For edge-lifting case, marked atomic-scale friction of the graphene sheet during the nanoscale peeling process is found. During the surface contact, the graphene sheet takes the atomic-scale sliding motion. The period of the peeling force curve during the surface contact decreases to the lattice period of the graphite. During the line contact, the graphene sheet also takes the stick-slip sliding motion. These findings indicate the possibility of not only the direct observation of the atomic-scale friction of the graphene sheet at the tip/surface interface but also the identification of the lattice orientation and the edge structure of the graphene sheet.

  16. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions...

  17. Mobility Balance Sheet 2009

    International Nuclear Information System (INIS)

    Jorritsma, P.; Derriks, H.; Francke, J.; Gordijn, H.; Groot, W.; Harms, L.; Van der Loop, H.; Peer, S.; Savelberg, F.; Wouters, P.

    2009-06-01

    The Mobility Balance Sheet provides an overview of the state of the art of mobility in the Netherlands. In addition to describing the development of mobility this report also provides explanations for the growth of passenger and freight transport. Moreover, the Mobility Balance Sheet also focuses on a topical theme: the effects of economic crises on mobility. [nl

  18. At the Tipping Point

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, H. S.

    2011-02-28

    There comes a time in every field of science when things suddenly change. While it might not be immediately apparent that things are different, a tipping point has occurred. Biology is now at such a point. The reason is the introduction of high-throughput genomics-based technologies. I am not talking about the consequences of the sequencing of the human genome (and every other genome within reach). The change is due to new technologies that generate an enormous amount of data about the molecular composition of cells. These include proteomics, transcriptional profiling by sequencing, and the ability to globally measure microRNAs and post-translational modifications of proteins. These mountains of digital data can be mapped to a common frame of reference: the organism’s genome. With the new high-throughput technologies, we can generate tens of thousands of data points from each sample. Data are now measured in terabytes and the time necessary to analyze data can now require years. Obviously, we can’t wait to interpret the data fully before the next experiment. In fact, we might never be able to even look at all of it, much less understand it. This volume of data requires sophisticated computational and statistical methods for its analysis and is forcing biologists to approach data interpretation as a collaborative venture.

  19. Tipping the scales.

    Science.gov (United States)

    1998-12-01

    In the US, the October 1998 murder of a physician who performed abortions was an outward manifestation of the insidious battle against legal abortion being waged by radical Christian social conservatives seeking to transform the US democracy into a theocracy. This movement has been documented in a publication entitled, "Tipping the Scales: The Christian Right's Legal Crusade Against Choice" produced as a result of a 4-year investigation conducted by The Center for Reproductive Law and Policy. This publication describes how these fundamentalists have used sophisticated legal, lobbying, and communication strategies to further their goals of challenging the separation of church and state, opposing family planning and sexuality education that is not based solely on abstinence, promoting school prayer, and restricting homosexual rights. The movement has resulted in the introduction of more than 300 anti-abortion bills in states, 50 of which have passed in 23 states. Most Christian fundamentalist groups provide free legal representation to abortion clinic terrorists, and some groups solicit women to bring specious malpractice claims against providers. Sophisticated legal tactics are used by these groups to remove the taint of extremism and mask the danger posed to US constitutional principles being posed by "a well-financed and zealous brand of radical lawyers and their supporters."

  20. STSHV a teleinformatic system for historic seismology in Venezuela

    Science.gov (United States)

    Choy, J. E.; Palme, C.; Altez, R.; Aranguren, R.; Guada, C.; Silva, J.

    2013-05-01

    From 1997 on, when the first "Jornadas Venezolanas de Sismicidad Historica" took place, a big interest awoke in Venezuela to organize the available information related to historic earthquakes. At that moment only existed one published historic earthquake catalogue, that from Centeno Grau published the first time in 1949. That catalogue had no references about the sources of information. Other catalogues existed but they were internal reports for the petroleum companies and therefore difficult to access. In 2000 Grases et al reedited the Centeno-Grau catalogue, it ended up in a new, very complete catalogue with all the sources well referenced and updated. The next step to organize historic seismicity data was, from 2004 to 2008, the creation of the STSHV (Sistema de teleinformacion de Sismologia Historica Venezolana, http://sismicidad.hacer.ula.ve ). The idea was to bring together all information about destructive historic earthquakes in Venezuela in one place in the internet so it could be accessed easily by a widespread public. There are two ways to access the system. The first one, selecting an earthquake or a list of earthquakes, and the second one, selecting an information source or a list of sources. For each earthquake there is a summary of general information and additional materials: a list with the source parameters published by different authors, a list with intensities assessed by different authors, a list of information sources, a short text summarizing the historic situation at the time of the earthquake and a list of pictures if available. There are searching facilities for the seismic events and dynamic maps can be created. The information sources are classified in: books, handwritten documents, transcription of handwritten documents, documents published in books, journals and congress memories, newspapers, seismologic catalogues and electronic sources. There are facilities to find specific documents or lists of documents with common characteristics

  1. Regional dependence in earthquake early warning and real time seismology

    International Nuclear Information System (INIS)

    Caprio, M.

    2013-01-01

    An effective earthquake prediction method is still a Chimera. What we can do at the moment, after the occurrence of a seismic event, is to provide the maximum available information as soon as possible. This can help in reducing the impact of the quake on population or and better organize the rescue operations in case of post-event actions. This study strives to improve the evaluation of earthquake parameters shortly after the occurrence of a major earthquake, and the characterization of regional dependencies in Real-Time Seismology. The recent earthquake experience from Tohoku (M 9.0, 11.03.2011) showed how an efficient EEW systems can inform numerous people and thus potentially reduce the economic and human losses by distributing warning messages several seconds before the arrival of seismic waves. In the case of devastating earthquakes, usually, in the first minutes to days after the main shock, the common communications channels can be overloaded or broken. In such cases, a precise knowledge of the macroseismic intensity distribution will represent a decisive contribution in help management and in the valuation of losses. In this work, I focused on improving the adaptability of EEW systems (chapters 1 and 2) and in deriving a global relationship for converting peak ground motion into macroseismic intensity and vice versa (chapter 3). For EEW applications, in chapter 1 we present an evolutionary approach for magnitude estimation for earthquake early warning based on real-time inversion of displacement spectra. The Spectrum Inversion (SI) method estimates magnitude and its uncertainty by inferring the shape of the entire displacement spectral curve based on the part of the spectra constrained by available data. Our method can be applied in any region without the need for calibration. SI magnitude and uncertainty estimates are updated each second following the initial P detection and potentially stabilize within 10 seconds from the initial earthquake detection

  2. Regional dependence in earthquake early warning and real time seismology

    Energy Technology Data Exchange (ETDEWEB)

    Caprio, M.

    2013-07-01

    An effective earthquake prediction method is still a Chimera. What we can do at the moment, after the occurrence of a seismic event, is to provide the maximum available information as soon as possible. This can help in reducing the impact of the quake on population or and better organize the rescue operations in case of post-event actions. This study strives to improve the evaluation of earthquake parameters shortly after the occurrence of a major earthquake, and the characterization of regional dependencies in Real-Time Seismology. The recent earthquake experience from Tohoku (M 9.0, 11.03.2011) showed how an efficient EEW systems can inform numerous people and thus potentially reduce the economic and human losses by distributing warning messages several seconds before the arrival of seismic waves. In the case of devastating earthquakes, usually, in the first minutes to days after the main shock, the common communications channels can be overloaded or broken. In such cases, a precise knowledge of the macroseismic intensity distribution will represent a decisive contribution in help management and in the valuation of losses. In this work, I focused on improving the adaptability of EEW systems (chapters 1 and 2) and in deriving a global relationship for converting peak ground motion into macroseismic intensity and vice versa (chapter 3). For EEW applications, in chapter 1 we present an evolutionary approach for magnitude estimation for earthquake early warning based on real-time inversion of displacement spectra. The Spectrum Inversion (SI) method estimates magnitude and its uncertainty by inferring the shape of the entire displacement spectral curve based on the part of the spectra constrained by available data. Our method can be applied in any region without the need for calibration. SI magnitude and uncertainty estimates are updated each second following the initial P detection and potentially stabilize within 10 seconds from the initial earthquake detection

  3. A uniform seismological bulletin for the European - Mediterranean region

    International Nuclear Information System (INIS)

    Bossu, R.; Piedfroid, O.; Riviere, F.

    2002-01-01

    The goal of this EU funded project is to develop means and tools to produce a homogeneous European-Mediterranean seismic bulletin that could serve as a reference. The 3 main objectives are 1) the definition of a unified magnitude scale for M > 3, 2) an improved location of events especially in border regions, 3) Improving rapid and regular data exchange within the European-Mediterranean region. The first step is to define an homogeneous and accurate magnitude estimation for the whole region of interest. Experience shows that the differences in the magnitudes reported by several institutes for a given event may vary up to 1.5 units. Three different magnitude computations are applied on a reference data set of well known events: a Lg waves coda magnitude, a Richter local magnitude and a moment magnitude scale. The comparison of the results is currently carried out. The algorithm associated to the selected magnitude will be implemented locally on a set of stations. New velocity models for border regions are developed from the analysis of the residuals of events recorded by permanent and temporary networks. The robustness and reliability of the 3D models versus 1D model have been evaluated. EMSC gathers via e-mail manually picked seismic phase arrival times with or without associated locations from about 50 seismological institutes of the European- Mediterranean region in a database. These bulletins are automatically merged by unique software. The number of processed events is about 2000 / month and should grow significantly with larger input from Middle East and Northern Africa. Events are then submitted to an automatic analysis of the location reliability, and, for dubious events, to a manual reprocessing. In order to improve data exchange, the installation of autoDRM systems is promoted. (authors)

  4. Monitoring the englacial fracture state using virtual-reflector seismology

    Science.gov (United States)

    Lindner, F.; Weemstra, C.; Walter, F.; Hadziioannou, C.

    2017-12-01

    Fracturing and changes in the englacial macroscopic water content change the elastic bulk properties of ice bodies. Small seismic velocity variations, resulting from such changes, can be measured using a technique called coda-wave interferometry. Here, coda refers to the later-arriving, multiply scattered waves. Often, this technique is applied to so-called virtual-source responses, which can be obtained using seismic interferometry (a simple crosscorrelation process). Compared to other media (e.g., the Earth's crust), however, ice bodies exhibit relatively little scattering. This complicates the application of coda-wave interferometry to the retrieved virtual-source responses. In this work, we therefore investigate the applicability of coda-wave interferometry to virtual-source responses obtained using two alternative seismic interferometric techniques, namely, seismic interferometry by multidimensional deconvolution (SI by MDD), and virtual-reflector seismology (VRS). To that end, we use synthetic data, as well as active-source glacier data acquired on Glacier de la Plaine Morte, Switzerland. Both SI by MDD and VRS allow the retrieval of more accurate virtual-source responses. In particular, the dependence of the retrieved virtual-source responses on the illumination pattern is reduced. We find that this results in more accurate glacial phase-velocity estimates. In addition, VRS introduces virtual reflections from a receiver contour (partly) enclosing the medium of interest. By acting as a sort of virtual reverberation, the coda resulting from the application of VRS significantly increases seismic monitoring capabilities, in particular in cases where natural scattering coda is not available.

  5. Accuracy assessment of high-rate GPS measurements for seismology

    Science.gov (United States)

    Elosegui, P.; Davis, J. L.; Ekström, G.

    2007-12-01

    Analysis of GPS measurements with a controlled laboratory system, built to simulate the ground motions caused by tectonic earthquakes and other transient geophysical signals such as glacial earthquakes, enables us to assess the technique of high-rate GPS. The root-mean-square (rms) position error of this system when undergoing realistic simulated seismic motions is 0.05~mm, with maximum position errors of 0.1~mm, thus providing "ground truth" GPS displacements. We have acquired an extensive set of high-rate GPS measurements while inducing seismic motions on a GPS antenna mounted on this system with a temporal spectrum similar to real seismic events. We found that, for a particular 15-min-long test event, the rms error of the 1-Hz GPS position estimates was 2.5~mm, with maximum position errors of 10~mm, and the error spectrum of the GPS estimates was approximately flicker noise. These results may however represent a best-case scenario since they were obtained over a short (~10~m) baseline, thereby greatly mitigating baseline-dependent errors, and when the number and distribution of satellites on the sky was good. For example, we have determined that the rms error can increase by a factor of 2--3 as the GPS constellation changes throughout the day, with an average value of 3.5~mm for eight identical, hourly-spaced, consecutive test events. The rms error also increases with increasing baseline, as one would expect, with an average rms error for a ~1400~km baseline of 9~mm. We will present an assessment of the accuracy of high-rate GPS based on these measurements, discuss the implications of this study for seismology, and describe new applications in glaciology.

  6. Expanding Horizons in Mitigating Earthquake Related Disasters in Urban Areas: Global Development of Real-Time Seismology

    OpenAIRE

    Utkucu, Murat; Küyük, Hüseyin Serdar; Demir, İsmail Hakkı

    2016-01-01

    Abstract Real-time seismology is a newly developing alternative approach in seismology to mitigate earthquake hazard. It exploits up-to-date advances in seismic instrument technology, data acquisition, digital communications and computer systems for quickly transforming data into earthquake information in real-time to reduce earthquake losses and its impact on social and economic life in the earthquake prone densely populated urban and industrial areas.  Real-time seismology systems are not o...

  7. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... echoes from the tissues in the body. The principles are similar to sonar used by boats and ... bleeding resistant to traditional medical treatments. The greatest difference in performing TIPS in children is their tremendous ...

  8. Fitness: Tips for Staying Motivated

    Science.gov (United States)

    Healthy Lifestyle Fitness Fitness is for life. Motivate yourself with these practical tips. By Mayo Clinic Staff Have ... 27, 2015 Original article: http://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/fitness/art-20047624 . Mayo Clinic ...

  9. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... deeply you are sedated. When the needle is advanced through the liver and the pathway is expanded ... are the limitations of TIPS? Patients with more advanced liver disease are at greater risk for worsening ...

  10. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... to determine the severity of the condition. To help plan for the placement of the TIPS stent, ... Radiological Society of North America, Inc. (RSNA). To help ensure current and accurate information, we do not ...

  11. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... avoiding the liver. TIPS may successfully reduce internal bleeding in the stomach and esophagus in patients with ... stomach, lower esophagus, and intestines, causing enlarged vessels, bleeding and the accumulation of fluid in the chest ...

  12. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... in the chest or abdomen. This condition is most commonly seen in adults, often as a result ... minimally invasive procedures such as a TIPS are most often performed by a specially trained interventional radiologist ...

  13. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... open. Patients who typically need a TIPS have portal hypertension , meaning they have increased pressure in the portal ... problems leading to cirrhosis (scarring of the liver). Portal hypertension can also occur in children, although children are ...

  14. Energy Savers: Cool Summer Tips

    International Nuclear Information System (INIS)

    Miller, M.

    2001-01-01

    A tri-fold brochure addressing energy-saving tips for homeowners ranging from low- or no-cost suggestions to higher cost suggestions for longer-term savings. Cooling, windows, weatherizing, and landscaping are addressed

  15. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... complex and lengthy procedures requiring extended fluoroscopy use) death (rare) top of page What are the limitations ... filtered out by the liver. The TIPS may cause too much of these substances to bypass the ...

  16. Girlfriends' Health and Safety Tips

    Science.gov (United States)

    ... in Women? Women's Safety and Health Issues at Work Health Equity Girlfriends' Health and Safety Tips Recommend on Facebook Tweet Share Compartir Having friends is an important part of life. Celebrate female friendship and support your girlfriends by ...

  17. Search Tips: MedlinePlus

    Science.gov (United States)

    ... of this page: https://medlineplus.gov/searchtips.html Search Tips To use the sharing features on this page, please enable JavaScript. How do I search MedlinePlus? The search box appears at the top ...

  18. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... you are pregnant and discuss any recent illnesses, medical conditions, allergies and medications you’re taking. You ... with ascites or variceal bleeding resistant to traditional medical treatments. The greatest difference in performing TIPS in ...

  19. Computerized automatic tip scanning operation

    International Nuclear Information System (INIS)

    Nishikawa, K.; Fukushima, T.; Nakai, H.; Yanagisawa, A.

    1984-01-01

    In BWR nuclear power stations the Traversing Incore Probe (TIP) system is one of the most important components in reactor monitoring and control. In previous TIP systems, however, operators have suffered from the complexity of operation and long operation time required. The system presented in this paper realizes the automatic operation of the TIP system by monitoring and driving it with a process computer. This system significantly reduces the burden on customer operators and improves plant efficiency by simplifying the operating procedure, augmenting the accuracy of the measured data, and shortening operating time. The process computer is one of the PODIA (Plant Operation by Displayed Information Automation) systems. This computer transfers control signals to the TIP control panel, which in turn drives equipment by microprocessor control. The process computer contains such components as the CRT/KB unit, the printer plotter, the hard copier, and the message typers required for efficient man-machine communications. Its operation and interface properties are described

  20. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the TIPS. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient Center This ... To locate a medical imaging or radiation oncology provider in your community, you can search the ACR- ...

  1. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in ...

  2. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... surgery. Your TIPS should have less of an effect than open surgical bypass on future liver transplantation ... Encephalopathy can be treated with certain medications, a special diet or, by revising the stent, but sometimes ...

  3. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in ... limitations of TIPS? Patients with more advanced liver disease are at greater risk for worsening liver failure ...

  4. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... is completed. top of page What are the benefits vs. risks? Benefits A TIPS is designed to produce the same ... risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in ...

  5. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... hepatic vein to identify the portal venous system. Access is then gained from the hepatic vein into ... TIPS procedure to make sure that it remains open and functions properly. top of page Who interprets ...

  6. Tips to Prevent Mosquito Bites

    Science.gov (United States)

    ... discourage mosquitoes, ticks and other biting insects from landing on you. Here are tips for other preventive ... CDC Mosquito Control Methods - NPIC Exit Top of Page Contact Us to ask a question, provide feedback, ...

  7. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... while avoiding the liver. TIPS may successfully reduce internal bleeding in the stomach and esophagus in patients ... site. Using ultrasound, the doctor will identify your internal jugular vein , which is situated above your collarbone, ...

  8. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... and medical diseases. This can result in significant challenges in creating the TIPS. top of page Additional ... Please note RadiologyInfo.org is not a medical facility. Please contact your physician with specific medical questions ...

  9. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the TIPS. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient Center This ... here Images × Image Gallery Radiologist and patient consultation. View full size with caption Pediatric Content Some imaging ...

  10. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams Contrast Materials Venography Images related to Transjugular Intrahepatic Portosystemic Shunt (TIPS) Sponsored ...

  11. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... story about radiology? Share your patient story here Images × Image Gallery Radiologist and patient consultation. View full size ... X-Ray and CT Exams Contrast Materials Venography Images related to Transjugular Intrahepatic Portosystemic Shunt (TIPS) Sponsored ...

  12. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... observed. This procedure is usually completed in an hour or two but may take up to several ...

  13. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the portal system using a TIPS needle (a special long needle extending from the neck into the ... Encephalopathy can be treated with certain medications, a special diet or, by revising the stent, but sometimes ...

  14. (Allium cepa) root tip mitosis

    African Journals Online (AJOL)

    Aghomotsegin

    their chemical composition and genotoxic effects on cell reproduction. Two petrochemicals, air ... the chromosomes of the individual cells of the root tip could be a pointer to their ..... Chromosome technique: Theory and. Practice. Butterworths ...

  15. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... Intrahepatic Portosystemic Shunt (TIPS)? What are some common uses of the procedure? How should I prepare? What does the equipment look like? How does the procedure work? How is the procedure performed? What will I ...

  16. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... in creating the TIPS. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient ... Send us your feedback Did you find the information you were looking for? Yes No Please type ...

  17. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... of bleeding that can occur can sometimes be life threatening and those patients are monitored in intensive ...

  18. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... blood draining from the bowel back to the heart while avoiding the liver. TIPS may successfully reduce ... blood away from the liver back to the heart). A stent is then placed in this tunnel ...

  19. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... portal vein to the hepatic vein in the liver. A small metal device called a stent is ... bowel back to the heart while avoiding the liver. TIPS may successfully reduce internal bleeding in the ...

  20. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose ...

  1. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... the liver. A small metal device called a stent is placed to keep the connection open and ... a small, tubular metal device commonly called a stent . During a TIPS procedure, interventional radiologists use image ...

  2. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... who typically need a TIPS have portal hypertension , meaning they have increased pressure in the portal vein ... the local anesthetic is injected. Most of the sensation is at the skin incision site, which is ...

  3. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... physician will numb an area just above your right collarbone with a local anesthetic . A very small ...

  4. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits A TIPS is designed to produce the ... skin that does not have to be stitched. Risks Any procedure where the skin is penetrated carries ...

  5. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... Patients who typically need a TIPS have portal hypertension , meaning they have increased pressure in the portal ... leading to cirrhosis (scarring of the liver). Portal hypertension can also occur in children, although children are ...

  6. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... pressure. top of page How does the procedure work? A TIPS reroutes blood flow in the liver ... above your collarbone, and guide a catheter, a long, thin, hollow plastic tube into the vessel. Using ...

  7. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... This can result in significant challenges in creating the TIPS. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient Center This page ...

  8. Evaluation of Aircraft Wing-Tip Vortex Using PIV

    Science.gov (United States)

    Alsayed, Omer A.; Asrar, Waqar; Omar, Ashraf A.

    2010-06-01

    The formation and development of a wing-tip vortex in a near and extended near filed were studied experimentally. Particle image velocimetry was used in a wind tunnel to measure the tip vortex velocity field and hence investigate the flow structure in a wake of aircraft half-wing model. The purpose of this investigation is to evaluate the main features of the lift generated vortices in order to find ways to alleviate hazardous wake vortex encounters for follower airplanes during start and approach such that the increase in airport capacity can be achieved. First the wake structure at successive downstream planes crosswise to the axis of the wake vortices was investigated by measuring parameters such as core radius, maximum tangential velocities, vorticities and circulation distributions. The effect of different angles of attack setting on vortex parameters was examined at one downstream location. In very early stages the vortex sheet evolution makes the tip vortex to move inward and to the suction side of the wing. While the core radius and circulation distributions hardly vary with the downstream distance, noticeable differences for the same vortex parameters at different angles of attack settings were observed. The center of the wing tip vortices scatter in a circle of radius nearly equal to 1% of the mean wing chord and wandering amplitudes shows no direct dependence on the vortex strength but linearly increase with the downstream distance.

  9. Carbon sheet pumping

    International Nuclear Information System (INIS)

    Ohyabu, N.; Sagara, A.; Kawamura, T.; Motojima, O.; Ono, T.

    1993-07-01

    A new hydrogen pumping scheme has been proposed which controls recycling of the particles for significant improvement of the energy confinement in toroidal magnetic fusion devices. In this scheme, a part of the vacuum vessel surface near the divertor is covered with carbon sheets of a large surface area. Before discharge initiation, the sheets are baked up to 700 ∼ 1000degC to remove the previously trapped hydrogen atoms. After being cooled down to below ∼ 200degC, the unsaturated carbon sheets trap high energy charge exchange hydrogen atoms effectively during a discharge and overall pumping efficiency can be as high as ∼ 50 %. (author)

  10. Tip model of cold fission

    International Nuclear Information System (INIS)

    Goennenwein, F.; Boersig, B.

    1991-01-01

    Cold fission is defined to be the limiting case of nuclear fission where virtually all of the available energy is converted into the total kinetic energy of the fragments. The fragments have, therefore, to be born in or at least close to their respective ground states. Starting from the viewpoint that cold fission corresponds to most compact scission configurations, energy constraints have been exploited to calculate minimum tip distances between the two nascent fragments in binary fission. Crucial input parameters to this tip model of cold fission are the ground-state deformations of fragment nuclei. It is shown that the minimum tip distances being compatible with energy conservation vary strongly with both the mass and charge fragmentation of the fission prone nucleus. The tip distances refer to nuclei with equivalent sharp surfaces. In keeping with the size of the surface width of leptodermous nuclei, only configurations where the tip distances are smaller than a few fm may be considered as valid scission configurations. From a comparison with experimental data on cold fission this critical tip distance appears to be 3.0 fm for the model parameters chosen. Whenever the model calculation yields tip distances being smaller than the critical value, a necessary condition for attaining cold fission is considered to be fulfilled. It is shown that this criterion allows to understand in fair agreement with experiment which mass fragmentations are susceptible to lead to cold fission and which fragment-charge divisions are the most favored in each isobaric mass chain. Being based merely on energy arguments, the model cannot aim at predicting fragment yields in cold fission. However, the tip model proposed appears well suited to delineate the phase space where cold fission phenomena may come into sight. (orig.)

  11. Glacier seismology: eavesdropping on the ice-bed interface

    Science.gov (United States)

    Walter, F.; Röösli, C.

    2015-12-01

    Glacier sliding plays a central role in ice dynamics. A number of remote sensing and deep drilling initiatives have therefore focused on the ice-bed interface. Although these techniques have provided valuable insights into bed properties, they do not supply theorists with data of sufficient temporal and spatial resolution to rigorously test mathematical sliding laws. As an alternative, passive seismic techniques have gained popularity in glacier monitoring. Analysis of glacier-related seismic sources ('icequakes') has become a useful technique to study inaccessible regions of the cryosphere, including the ice-bed interface. Seismic monitoring networks on the polar ice sheets have shown that ice sliding is not only a smooth process involving viscous deformation and regelation of basal ice layers. Instead, ice streams exhibit sudden slip episodes over their beds and intermittent phases of partial or complete stagnation. Here we discuss new and recently published discoveries of basal seismic sources beneath various glacial bodies. We revisit basal seismicity of hard-bedded Alpine glaciers, which is not the result of pure stick-slip motion. Sudden changes in seismicity suggest that the local configuration of the subglacial drainage system undergoes changes on sub daily time scales. Accordingly, such observations place constraints on basal resistance and sliding of hard-bedded glaciers. In contrast, certain clusters of stick-slip dislocations associated with micro seismicity beneath the Greenland ice sheet undergo diurnal variations in magnitudes and inter event times. This is best explained with a soft till bed, which hosts the shear dislocations and whose strength varies in response to changes in subglacial water pressure. These results suggest that analysis of basal icequakes is well suited for characterizing glacier and ice sheet beds. Future studies should address the relative importance between "smooth" and seismogenic sliding in different glacial environments.

  12. Anesthesia Fact Sheet

    Science.gov (United States)

    ... Education About NIGMS NIGMS Home > Science Education > Anesthesia Anesthesia Tagline (Optional) Middle/Main Content Area En español ... Version (464 KB) Other Fact Sheets What is anesthesia? Anesthesia is a medical treatment that prevents patients ...

  13. Structural Biology Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  14. Radiation protecting sheet

    International Nuclear Information System (INIS)

    Makiguchi, Hiroshi.

    1989-01-01

    As protection sheets used in radioactivity administration areas, a thermoplastic polyurethane composition sheet with a thickness of less 0.5 mm, solid content (ash) of less than 5% and a shore D hardness of less than 60 is used. A composite sheet with thickness of less than 0.5 mm laminated or coated with such a thermoplastic polyurethane composition as a surface layer and the thermoplastic polyurethane composition sheet applied with secondary fabrication are used. This can satisfy all of the required properties, such as draping property, abrasion resistance, high breaking strength, necking resistance, endurance strength, as well as chemical resistance and easy burnability in burning furnace. Further, by forming uneveness on the surface by means of embossing, etc. safety problems such as slippage during operation and walking can be overcome. (T.M.)

  15. Global ice sheet modeling

    International Nuclear Information System (INIS)

    Hughes, T.J.; Fastook, J.L.

    1994-05-01

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

  16. Provenance for Runtime Workflow Steering and Validation in Computational Seismology

    Science.gov (United States)

    Spinuso, A.; Krischer, L.; Krause, A.; Filgueira, R.; Magnoni, F.; Muraleedharan, V.; David, M.

    2014-12-01

    Provenance systems may be offered by modern workflow engines to collect metadata about the data transformations at runtime. If combined with effective visualisation and monitoring interfaces, these provenance recordings can speed up the validation process of an experiment, suggesting interactive or automated interventions with immediate effects on the lifecycle of a workflow run. For instance, in the field of computational seismology, if we consider research applications performing long lasting cross correlation analysis and high resolution simulations, the immediate notification of logical errors and the rapid access to intermediate results, can produce reactions which foster a more efficient progress of the research. These applications are often executed in secured and sophisticated HPC and HTC infrastructures, highlighting the need for a comprehensive framework that facilitates the extraction of fine grained provenance and the development of provenance aware components, leveraging the scalability characteristics of the adopted workflow engines, whose enactment can be mapped to different technologies (MPI, Storm clusters, etc). This work looks at the adoption of W3C-PROV concepts and data model within a user driven processing and validation framework for seismic data, supporting also computational and data management steering. Validation needs to balance automation with user intervention, considering the scientist as part of the archiving process. Therefore, the provenance data is enriched with community-specific metadata vocabularies and control messages, making an experiment reproducible and its description consistent with the community understandings. Moreover, it can contain user defined terms and annotations. The current implementation of the system is supported by the EU-Funded VERCE (http://verce.eu). It provides, as well as the provenance generation mechanisms, a prototypal browser-based user interface and a web API built on top of a NoSQL storage

  17. Big Data and High-Performance Computing in Global Seismology

    Science.gov (United States)

    Bozdag, Ebru; Lefebvre, Matthieu; Lei, Wenjie; Peter, Daniel; Smith, James; Komatitsch, Dimitri; Tromp, Jeroen

    2014-05-01

    Much of our knowledge of Earth's interior is based on seismic observations and measurements. Adjoint methods provide an efficient way of incorporating 3D full wave propagation in iterative seismic inversions to enhance tomographic images and thus our understanding of processes taking place inside the Earth. Our aim is to take adjoint tomography, which has been successfully applied to regional and continental scale problems, further to image the entire planet. This is one of the extreme imaging challenges in seismology, mainly due to the intense computational requirements and vast amount of high-quality seismic data that can potentially be assimilated. We have started low-resolution inversions (T > 30 s and T > 60 s for body and surface waves, respectively) with a limited data set (253 carefully selected earthquakes and seismic data from permanent and temporary networks) on Oak Ridge National Laboratory's Cray XK7 "Titan" system. Recent improvements in our 3D global wave propagation solvers, such as a GPU version of the SPECFEM3D_GLOBE package, will enable us perform higher-resolution (T > 9 s) and longer duration (~180 m) simulations to take the advantage of high-frequency body waves and major-arc surface waves, thereby improving imbalanced ray coverage as a result of the uneven global distribution of sources and receivers. Our ultimate goal is to use all earthquakes in the global CMT catalogue within the magnitude range of our interest and data from all available seismic networks. To take the full advantage of computational resources, we need a solid framework to manage big data sets during numerical simulations, pre-processing (i.e., data requests and quality checks, processing data, window selection, etc.) and post-processing (i.e., pre-conditioning and smoothing kernels, etc.). We address the bottlenecks in our global seismic workflow, which are mainly coming from heavy I/O traffic during simulations and the pre- and post-processing stages, by defining new data

  18. Twitter Seismology: Earthquake Monitoring and Response in a Social World

    Science.gov (United States)

    Bowden, D. C.; Earle, P. S.; Guy, M.; Smoczyk, G.

    2011-12-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public, text messages, can augment USGS earthquake response products and the delivery of hazard information. The potential uses of Twitter for earthquake response include broadcasting earthquake alerts, rapidly detecting widely felt events, qualitatively assessing earthquake damage effects, communicating with the public, and participating in post-event collaboration. Several seismic networks and agencies are currently distributing Twitter earthquake alerts including the European-Mediterranean Seismological Centre (@LastQuake), Natural Resources Canada (@CANADAquakes), and the Indonesian meteorological agency (@infogempabmg); the USGS will soon distribute alerts via the @USGSted and @USGSbigquakes Twitter accounts. Beyond broadcasting alerts, the USGS is investigating how to use tweets that originate near the epicenter to detect and characterize shaking events. This is possible because people begin tweeting immediately after feeling an earthquake, and their short narratives and exclamations are available for analysis within 10's of seconds of the origin time. Using five months of tweets that contain the word "earthquake" and its equivalent in other languages, we generate a tweet-frequency time series. The time series clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a simple Short-Term-Average / Long-Term-Average algorithm similar to that commonly used to detect seismic phases. As with most auto-detection algorithms, the parameters can be tuned to catch more or less events at the cost of more or less false triggers. When tuned to a moderate sensitivity, the detector found 48 globally-distributed, confirmed seismic events with only 2 false triggers. A space-shuttle landing and "The Great California ShakeOut" caused the false triggers. This number of

  19. Energy information sheets

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  20. Montessus de Ballore, a pioneer of seismology: The man and his work

    Science.gov (United States)

    Cisternas, Armando

    2009-06-01

    Ferdinand de Montessus de Ballore was one of the founders of scientific seismology. He was a pioneer in seismology at the same level as Perrey, Mallet, Milne and Omori. He became familiar with earthquakes and volcanoes in Central America (1881-1885). After his experience in El Salvador his interest for understanding earthquakes and volcanoes oriented all of his life. Back in France he worked out a most complete world catalogue of earthquakes with 170.000 events (1885-1907), and completed his career being the head of the Chilean Seismological Service (1907-1923). Many of his ideas were in advance of later discoveries. He was an exceptional writer and published more than 30 books and hundreds of papers.

  1. ObsPy: A Python toolbox for seismology - Sustainability, New Features, and Applications

    Science.gov (United States)

    Krischer, L.; Megies, T.; Sales de Andrade, E.; Barsch, R.; MacCarthy, J.

    2016-12-01

    ObsPy (https://www.obspy.org) is a community-driven, open-source project dedicated to offer a bridge for seismology into the scientific Python ecosystem. Amongst other things, it provides Read and write support for essentially every commonly used data format in seismology with a unified interface. This includes waveform data as well as station and event meta information. A signal processing toolbox tuned to the specific needs of seismologists. Integrated access to the largest data centers, web services, and databases. Wrappers around third party codes like libmseed and evalresp. Using ObsPy enables users to take advantage of the vast scientific ecosystem that has developed around Python. In contrast to many other programming languages and tools, Python is simple enough to enable an exploratory and interactive coding style desired by many scientists. At the same time it is a full-fledged programming language usable by software engineers to build complex and large programs. This combination makes it very suitable for use in seismology where research code often must be translated to stable and production ready environments, especially in the age of big data. ObsPy has seen constant development for more than six years and enjoys a large rate of adoption in the seismological community with thousands of users. Successful applications include time-dependent and rotational seismology, big data processing, event relocations, and synthetic studies about attenuation kernels and full-waveform inversions to name a few examples. Additionally it sparked the development of several more specialized packages slowly building a modern seismological ecosystem around it. We will present a short overview of the capabilities of ObsPy and point out several representative use cases and more specialized software built around ObsPy. Additionally we will discuss new and upcoming features, as well as the sustainability of open-source scientific software.

  2. Risk-analysis of global climate tipping points

    Energy Technology Data Exchange (ETDEWEB)

    Frieler, Katja; Meinshausen, Malte; Braun, N [Potsdam Institute for Climate Impact Research e.V., Potsdam (Germany). PRIMAP Research Group; and others

    2012-09-15

    There are many elements of the Earth system that are expected to change gradually with increasing global warming. Changes might prove to be reversible after global warming returns to lower levels. But there are others that have the potential of showing a threshold behavior. This means that these changes would imply a transition between qualitatively disparate states which can be triggered by only small shifts in background climate (2). These changes are often expected not to be reversible by returning to the current level of warming. The reason for that is, that many of them are characterized by self-amplifying processes that could lead to a new internally stable state which is qualitatively different from before. There are different elements of the climate system that are already identified as potential tipping elements. This group contains the mass losses of the Greenland and the West-Antarctic Ice Sheet, the decline of the Arctic summer sea ice, different monsoon systems, the degradation of coral reefs, the dieback of the Amazon rainforest, the thawing of the permafrost regions as well as the release of methane hydrates (3). Crucially, these tipping elements have regional to global scale effects on human society, biodiversity and/or ecosystem services. Several examples may have a discernable effect on global climate through a large-scale positive feedback. This means they would further amplify the human induced climate change. These tipping elements pose risks comparable to risks found in other fields of human activity: high-impact events that have at least a few percent chance to occur classify as high-risk events. In many of these examples adaptation options are limited and prevention of occurrence may be a more viable strategy. Therefore, a better understanding of the processes driving tipping points is essential. There might be other tipping elements even more critical but not yet identified. These may also lie within our socio-economic systems that are

  3. 10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Geological and seismological characteristics for... § 72.103 Geological and seismological characteristics for applications for dry cask modes of storage on... foundation and geological investigation, literature review, and regional geological reconnaissance show no...

  4. Magnetic seismology of interstellar gas clouds: Unveiling a hidden dimension.

    Science.gov (United States)

    Tritsis, Aris; Tassis, Konstantinos

    2018-05-11

    Stars and planets are formed inside dense interstellar molecular clouds by processes imprinted on the three-dimensional (3D) morphology of the clouds. Determining the 3D structure of interstellar clouds remains challenging because of projection effects and difficulties measuring the extent of the clouds along the line of sight. We report the detection of normal vibrational modes in the isolated interstellar cloud Musca, allowing determination of the 3D physical dimensions of the cloud. We found that Musca is vibrating globally, with the characteristic modes of a sheet viewed edge on, not the characteristics of a filament as previously supposed. We reconstructed the physical properties of Musca through 3D magnetohydrodynamic simulations, reproducing the observed normal modes and confirming a sheetlike morphology. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  5. Root tips moving through soil

    Science.gov (United States)

    Curlango-Rivera, Gilberto

    2011-01-01

    Root elongation occurs by the generation of new cells from meristematic tissue within the apical 1–2 mm region of root tips. Therefore penetration of the soil environment is carried out by newly synthesized plant tissue, whose cells are inherently vulnerable to invasion by pathogens. This conundrum, on its face, would seem to reflect an intolerable risk to the successful establishment of root systems needed for plant life. Yet root tip regions housing the meristematic tissues repeatedly have been found to be free of microbial infection and colonization. Even when spore germination, chemotaxis, and/or growth of pathogens are stimulated by signals from the root tip, the underlying root tissue can escape invasion. Recent insights into the functions of root border cells, and the regulation of their production by transient exposure to external signals, may shed light on long-standing observations. PMID:21455030

  6. Crack tip stress and strain

    International Nuclear Information System (INIS)

    Francois, D.

    1975-01-01

    The study of potential energy variations in a loaded elastic solid containing a crack leads to determination of the crack driving force G. Generalization of this concept to cases other than linear elasticity leads to definition of the integral J. In a linear solid, the crack tip stress field is characterized by a single parameter: the stress-intensity factor K. When the crack tip plastic zone size is confined to the elastic singularity J=G, it is possible to establish relationship between these parameters and plastic strain (and in particular the crack tip opening displacement delta). The stress increases because of the triaxiality effect. This overload rises with increasing strain hardening. When the plastic zone size expands, using certain hypotheses, delta can be calculated. The plastic strain intensity is exclusively dependent on parameter J [fr

  7. Optical fiber meta-tips

    Science.gov (United States)

    Principe, Maria; Micco, Alberto; Crescitelli, Alessio; Castaldi, Giuseppe; Consales, Marco; Esposito, Emanuela; La Ferrara, Vera; Galdi, Vincenzo; Cusano, Andrea

    2016-04-01

    We report on the first example of a "meta-tip" configuration that integrates a metasurface on the tip of an optical fiber. Our proposed design is based on an inverted-Babinet plasmonic metasurface obtained by patterning (via focused ion beam) a thin gold film deposited on the tip of an optical fiber, so as to realize an array of rectangular aperture nanoantennas with spatially modulated sizes. By properly tuning the resonances of the aperture nanoantennas, abrupt variations can be impressed in the field wavefront and polarization. We fabricated and characterized several proof-of-principle prototypes operating an near-infrared wavelengths, and implementing the beam-steering (with various angles) of the cross-polarized component, as well as the excitation of surface waves. Our results pave the way to the integration of the exceptional field-manipulation capabilities enabled by metasurfaces with the versatility and ubiquity of fiber-optics technological platforms.

  8. ZBrush Professional Tips and Techniques

    CERN Document Server

    Gaboury, Paul

    2012-01-01

    Learn to work effectively and creatively with all versions of ZBrush! ZBrush is used by top artists in Hollywood to model and sculpt characters in such films as Avatar, Iron Man, and Pirates of the Caribbean. In addition, this amazing technology is also used in jewelry design, forensic science, aerospace, video games, toy creation, and the medical field. Written by Pixologic's in-house ZBrush expert Paul Gaboury, this full-color, beautifully illustrated guide provides you with the ultimate tips and tricks to maximize your use of all versions of ZBrush. Reveals numerous little-known tips and tr

  9. Disintegration of liquid sheets

    Science.gov (United States)

    Mansour, Adel; Chigier, Norman

    1990-01-01

    The development, stability, and disintegration of liquid sheets issuing from a two-dimensional air-assisted nozzle is studied. Detailed measurements of mean drop size and velocity are made using a phase Doppler particle analyzer. Without air flow the liquid sheet converges toward the axis as a result of surface tension forces. With airflow a quasi-two-dimensional expanding spray is formed. The air flow causes small variations in sheet thickness to develop into major disturbances with the result that disruption starts before the formation of the main break-up region. In the two-dimensional variable geometry air-blast atomizer, it is shown that the air flow is responsible for the formation of large, ordered, and small chaotic 'cell' structures.

  10. Safety advice sheets

    CERN Multimedia

    HSE Unit

    2013-01-01

    You never know when you might be faced with questions such as: when/how should I dispose of a gas canister? Where can I find an inspection report? How should I handle/store/dispose of a chemical substance…?   The SI section of the DGS/SEE Group is primarily responsible for safety inspections, evaluating the safety conditions of equipment items, premises and facilities. On top of this core task, it also regularly issues “Safety Advice Sheets” on various topics, designed to be of assistance to users but also to recall and reinforce safety rules and procedures. These clear and concise sheets, complete with illustrations, are easy to display in the appropriate areas. The following safety advice sheets have been issued so far: Other sheets will be published shortly. Suggestions are welcome and should be sent to the SI section of the DGS/SEE Group. Please send enquiries to general-safety-visits.service@cern.ch.

  11. Network of Research Infrastructures for European Seismology (NERIES)—Web Portal Developments for Interactive Access to Earthquake Data on a European Scale

    OpenAIRE

    A. Spinuso; L. Trani; S. Rives; P. Thomy; F. Euchner; Danijel Schorlemmer; Joachim Saul; Andres Heinloo; R. Bossu; T. van Eck

    2009-01-01

    The Network of Research Infrastructures for European Seismology (NERIES) is European Commission (EC) project whose focus is networking together seismological observatories and research institutes into one integrated European infrastructure that provides access to data and data products for research. Seismological institutes and organizations in European and Mediterranean countries maintain large, geographically distributed data archives, therefore this scenario suggested a design approach bas...

  12. Ice Sheets & Ice Cores

    DEFF Research Database (Denmark)

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known....... The first part concerns time series analysis of ice core data obtained from the Greenland Ice Sheet. We analyze parts of the time series where DO-events occur using the so-called transfer operator and compare the results with time series from a simple model capable of switching by either undergoing...

  13. Energy information sheets

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-02

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. Written for the general public, the EIA publication Energy Information Sheets was developed to provide information on various aspects of fuel production, prices, consumption and capability. The information contained herein pertains to energy data as of December 1991. Additional information on related subject matter can be found in other EIA publications as referenced at the end of each sheet.

  14. Seismology and Research in Schools: One School's Experience

    Science.gov (United States)

    Tedd, Joe; Tedd, Bernie

    2018-01-01

    The UK School Seismology Project started in 2007. King Edward VI High School for Girls was one of the fortunate schools to obtain a school seismometer system, free of charge, as an early adopter of the resource. This report outlines our experiences with the system over the past 10 years and describes our recent research on the relationship between…

  15. The establishment of the Blacknest seismological database on the Rutherford Laboratory system 360/195 computer

    International Nuclear Information System (INIS)

    Blamey, C.

    1977-01-01

    In order to assess the problems which might arise from monitoring a comprehensive test ban treaty by seismological methods, an experimental monitoring operation is being conducted. This work has involved the establishment of a database on the Rutherford Laboratory 360/195 system computer. The database can be accessed in the UK over the public telephone network and in the USA via ARPANET. (author)

  16. Solving seismological problems using SGRAPH program: I-source parameters and hypocentral location

    International Nuclear Information System (INIS)

    Abdelwahed, Mohamed F.

    2012-01-01

    SGRAPH program is considered one of the seismological programs that maintain seismic data. SGRAPH is considered unique for being able to read a wide range of data formats and manipulate complementary tools in different seismological subjects in a stand-alone Windows-based application. SGRAPH efficiently performs the basic waveform analysis and solves advanced seismological problems. The graphical user interface (GUI) utilities and the Windows facilities such as, dialog boxes, menus, and toolbars simplified the user interaction with data. SGRAPH supported the common data formats like, SAC, SEED, GSE, ASCII, and Nanometrics Y-format, and others. It provides the facilities to solve many seismological problems with the built-in inversion and modeling tools. In this paper, I discuss some of the inversion tools built-in SGRAPH related to source parameters and hypocentral location estimation. Firstly, a description of the SGRAPH program is given discussing some of its features. Secondly, the inversion tools are applied to some selected events of the Dahshour earthquakes as an example of estimating the spectral and source parameters of local earthquakes. In addition, the hypocentral location of these events are estimated using the Hypoinverse 2000 program operated by SGRAPH.

  17. Jupyter Notebooks for Earth Sciences: An Interactive Training Platform for Seismology

    Science.gov (United States)

    Igel, H.; Chow, B.; Donner, S.; Krischer, L.; van Driel, M.; Tape, C.

    2017-12-01

    We have initiated a community platform (http://www.seismo-live.org) where Python-based Jupyter notebooks (https://jupyter.org) can be accessed and run without necessary downloads or local software installations. The increasingly popular Jupyter notebooks allow the combination of markup language, graphics, and equations with interactive, executable Python code examples. Jupyter notebooks are a powerful and easy-to-grasp tool for students to develop entire projects, scientists to collaborate and efficiently interchange evolving workflows, and trainers to develop efficient practical material. Utilizing the tmpnb project (https://github.com/jupyter/tmpnb), we link the power of Jupyter notebooks with an underlying server, such that notebooks can be run from anywhere, even on smart phones. We demonstrate the potential with notebooks for 1) learning the programming language Python, 2) basic signal processing, 3) an introduction to the ObsPy library (https://obspy.org) for seismology, 4) seismic noise analysis, 5) an entire suite of notebooks for computational seismology (the finite-difference method, pseudospectral methods, finite/spectral element methods, the finite-volume and the discontinuous Galerkin methods, Instaseis), 6) rotational seismology, 7) making results in papers fully reproducible, 8) a rate-and-state friction toolkit, 9) glacial seismology. The platform is run as a community project using Github. Submission of complementary Jupyter notebooks is encouraged. Extension in the near future include linear(-ized) and nonlinear inverse problems.

  18. The EGU Seismology Division Early Career Scientist Representative team and its initiatives

    Science.gov (United States)

    Parisi, Laura; Ermert, Laura; Gualtieri, Lucia; Spieker, Kathrin; Van Noten, Koen; Agius, Matthew R.; Mai, P. Martin

    2017-04-01

    Since 2014, the Seismology Division (SM) of the European Geosciences Union (EGU) has its Early Career Scientist (ECS) representative to reach out to its numerous 'younger' members. In April 2016, a new team of representatives joined the Division. We are a vivid team of early career scientists, representing both (either) PhD students and post-doctoral researchers working in different seismological disciplines and different countries. The initiatives of the SM ECS-rep team have various aims: (1) to motivate the ECSs to get involved in activities and initiatives of the EGU and the Seismology Division, (2) to promote the research of ECSs, (3) to discuss issues concerning seismologists during this particular stage of their career, (4) to share ideas on how to promote equality between scientists and (5) to improve on the public dissemination of scientific knowledge. In an effort to reach out to experienced and ECS seismologists more effectively and to continuously encourage to voice their ideas by contributing and following our initiatives, a blog and social media pages dedicated to seismology and earthquake trivia are run by the team. Weekly posts are published on the blog and shared on the social media regarding scientific and social aspects of seismology. One of the major contributions recently introduced to the blog is the "Paper of the Month" series where experienced seismologists write about recent or classical - must read - seismology articles. We also aim to organise and promote social and scientific events. During the EGU General Assembly 2016 a social event was held in Vienna allowing ECS to network with peers in an informal environment. Given the success of this event, a similar event will be organized during the General Assembly 2017. Also, similar to previous years, a short course on basic seismology for non seismologists will be requested and offered to all ECSs attending the General Assembly. Finally, a workshop dedicated entirely to ECSs seismologists

  19. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... procedure work? How is the procedure performed? What will I experience during and after the procedure? Who interprets the results and how do I get them? What are the benefits vs. risks? What are the limitations of TIPS? ...

  20. Nanobits: customizable scanning probe tips

    DEFF Research Database (Denmark)

    Kumar, Rajendra; Shaik, Hassan Uddin; Sardan Sukas, Özlem

    2009-01-01

    We present here a proof-of-principle study of scanning probe tips defined by planar nanolithography and integrated with AFM probes using nanomanipulation. The so-called 'nanobits' are 2-4 mu m long and 120-150 nm thin flakes of Si3N4 or SiO2, fabricated by electron beam lithography and standard s...

  1. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... thin, hollow plastic tube into the vessel. Using real time x-ray guidance, your doctor will then guide ... invasive procedure that typically has a shorter recovery time than surgery. Your TIPS should have less of an effect ...

  2. The tip of the iceberg

    DEFF Research Database (Denmark)

    Bjørst, Lill Rastad

    2010-01-01

      Abstract: The tip of the iceberg: Ice as a nonhuman actor of the climate change debate   The global climate change debate has the Arctic as a core region of concern and ice has become a central aspect of discourses. This article discusses ice representations from six different contexts linked...

  3. Gardening Health and Safety Tips

    Science.gov (United States)

    ... or who take certain medications (i.e. for depression, insomnia, or poor circulation). Eat healthy foods to help keep you energized. Extreme Heat Keep Your Cool in Hot Weather Tips for persons with disabilities and physical activity. Talk to your health care provider if you have physical, mental, or ...

  4. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... Portosystemic Shunt (TIPS) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ... links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo.org , ACR ...

  5. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    Medline Plus

    Full Text Available ... in creating the TIPS. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient Center This page ... of Use | Links | Site Map Copyright © 2018 ... To help ensure current and accurate information, we do not permit copying but encourage linking ...

  6. Useful Tips on Avoiding Plagiarism

    Science.gov (United States)

    Hamalainen, Maryellen

    2007-01-01

    Teachers are generally kind and nurturing people. Students who plagiarize their assignments from these kind and nurturing teachers are often given a second chance when caught and encouraged to do their work over, but it would be better to eliminate their need to plagiarize. The first tip for eliminating plagiarism has not so much to do with what…

  7. Assigning Effective Homework. Classroom Tips

    Science.gov (United States)

    American Federation of Teachers (NJ), 2010

    2010-01-01

    Each new school year brings high hopes, great expectations and challenges for both new and seasoned educators. The American Federation of Teachers (AFT) has developed a series called "Classroom Tips" to help educators start the year right and anticipate the year ahead. Over the past 40 years, most research studies on homework have found that…

  8. SGRAPH (SeismoGRAPHer): Seismic waveform analysis and integrated tools in seismology

    Science.gov (United States)

    Abdelwahed, Mohamed F.

    2012-03-01

    Although numerous seismological programs are currently available, most of them suffer from the inability to manipulate different data formats and the lack of embedded seismological tools. SeismoGRAPHer, or simply SGRAPH, is a new system for maintaining and analyzing seismic waveform data in a stand-alone, Windows-based application that manipulates a wide range of data formats. SGRAPH was intended to be a tool sufficient for performing basic waveform analysis and solving advanced seismological problems. The graphical user interface (GUI) utilities and the Windows functionalities, such as dialog boxes, menus, and toolbars, simplify the user interaction with the data. SGRAPH supports common data formats, such as SAC, SEED, GSE, ASCII, and Nanometrics Y-format, and provides the ability to solve many seismological problems with built-in inversion tools. Loaded traces are maintained, processed, plotted, and saved as SAC, ASCII, or PS (post script) file formats. SGRAPH includes Generalized Ray Theory (GRT), genetic algorithm (GA), least-square fitting, auto-picking, fast Fourier transforms (FFT), and many additional tools. This program provides rapid estimation of earthquake source parameters, location, attenuation, and focal mechanisms. Advanced waveform modeling techniques are provided for crustal structure and focal mechanism estimation. SGRAPH has been employed in the Egyptian National Seismic Network (ENSN) as a tool assisting with routine work and data analysis. More than 30 users have been using previous versions of SGRAPH in their research for more than 3 years. The main features of this application are ease of use, speed, small disk space requirements, and the absence of third-party developed components. Because of its architectural structure, SGRAPH can be interfaced with newly developed methods or applications in seismology. A complete setup file, including the SGRAPH package with the online user guide, is available.

  9. Promoting seismology education and research via the IRIS Education and Public Outreach Program

    Science.gov (United States)

    Taber, J. J.; Bravo, T. K.; Dorr, P. M.; Hubenthal, M.; Johnson, J. A.; McQuillan, P.; Sumy, D. F.; Welti, R.

    2015-12-01

    The Incorporated Research Institutions for Seismology's Education and Public Outreach (EPO) program is committed to advancing awareness and understanding of seismology and geophysics, while inspiring careers in the Earth sciences. To achieve this mission, IRIS EPO combines content and research expertise of consortium membership with educational and outreach expertise of IRIS staff to create a portfolio of programs, products, and services that target a range of audiences, including grades 6-12 students and teachers, undergraduate and graduate students, faculty, and the general public. IRIS also partners with UNAVCO and other organizations in support of EarthScope where the facilities are well-suited for sustained engagement of multiple audiences. Examples of research-related EPO products and services include the following resources. Tools developed in collaboration with IRIS Data Services provide public and educational access to data, and to a suite of data products. Teachers can stream seismic data from educational or research sensors into their classroom, and the Active Earth Monitor display, designed for visitor centers, universities and small museums, provides views of recent data along with animations that explain seismology concepts, and stories about recent research. Teachable Moment slide sets, created in collaboration with the University of Portland within 24 hours of major earthquakes, provide interpreted USGS tectonic maps and summaries, animations, visualizations, and other event-specific information so educators can explore newsworthy earthquakes with their students. Intro undergraduate classroom activities have been designed to introduce students to some grand challenges in seismological research, while our Research Experiences for Undergraduates program pairs students with seismology researchers throughout the Consortium and provides the opportunity for the students to present their research at a national meeting. EPO activities are evaluated via a

  10. Recent activities of the Seismology Division Early Career Representative(s)

    Science.gov (United States)

    Agius, Matthew; Van Noten, Koen; Ermert, Laura; Mai, P. Martin; Krawczyk, CharLotte

    2016-04-01

    The European Geosciences Union is a bottom-up-organisation, in which its members are represented by their respective scientific divisions, committees and council. In recent years, EGU has embarked on a mission to reach out for its numerous 'younger' members by giving awards to outstanding young scientists and the setting up of Early Career Scientists (ECS) representatives. The division representative's role is to engage in discussions that concern students and early career scientists. Several meetings between all the division representatives are held throughout the year to discuss ideas and Union-wide issues. One important impact ECS representatives have had on EGU is the increased number of short courses and workshops run by ECS during the annual General Assembly. Another important contribution of ECS representatives was redefining 'Young Scientist' to 'Early Career Scientist', which avoids discrimination due to age. Since 2014, the Seismology Division has its own ECS representative. In an effort to more effectively reach out for young seismologists, a blog and a social media page dedicated to seismology have been set up online. With this dedicated blog, we'd like to give more depth to the average browsing experience by enabling young researchers to explore various seismology topics in one place while making the field more exciting and accessible to the broader community. These pages are used to promote the latest research especially of young seismologists and to share interesting seismo-news. Over the months the pages proved to be popular, with hundreds of views every week and an increased number of followers. An online survey was conducted to learn more about the activities and needs of early career seismologists. We present the results from this survey, and the work that has been carried out over the last two years, including detail of what has been achieved so far, and what we would like the ECS representation for Seismology to achieve. Young seismologists are

  11. Collisionless current sheet equilibria

    Science.gov (United States)

    Neukirch, T.; Wilson, F.; Allanson, O.

    2018-01-01

    Current sheets are important for the structure and dynamics of many plasma systems. In space and astrophysical plasmas they play a crucial role in activity processes, for example by facilitating the release of magnetic energy via processes such as magnetic reconnection. In this contribution we will focus on collisionless plasma systems. A sensible first step in any investigation of physical processes involving current sheets is to find appropriate equilibrium solutions. The theory of collisionless plasma equilibria is well established, but over the past few years there has been a renewed interest in finding equilibrium distribution functions for collisionless current sheets with particular properties, for example for cases where the current density is parallel to the magnetic field (force-free current sheets). This interest is due to a combination of scientific curiosity and potential applications to space and astrophysical plasmas. In this paper we will give an overview of some of the recent developments, discuss their potential applications and address a number of open questions.

  12. Cholera Fact Sheet

    Science.gov (United States)

    ... news-room/fact-sheets/detail/cholera","@context":"http://schema.org","@type":"Article"}; العربية 中文 français русский español ... that includes feedback at the local level and information-sharing at the global level. Cholera cases are ...

  13. Pseudomonas - Fact Sheet

    OpenAIRE

    Public Health Agency

    2012-01-01

    Fact sheet on Pseudomonas, including:What is Pseudomonas?What infections does it cause?Who is susceptible to pseudomonas infection?How will I know if I have pseudomonas infection?How can Pseudomonas be prevented from spreading?How can I protect myself from Pseudomonas?How is Pseudomonas infection treated?

  14. NTPR Fact Sheets

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  15. Production (information sheets)

    NARCIS (Netherlands)

    2007-01-01

    Documentation sheets: Geo energy 2 Integrated System Approach Petroleum Production (ISAPP) The value of smartness 4 Reservoir permeability estimation from production data 6 Coupled modeling for reservoir application 8 Toward an integrated near-wellbore model 10 TNO conceptual framework for "E&P

  16. Hibernia fact sheet

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This fact sheet gives details of the Hibernia oil field including its location, discovery date, oil company's interests in the project, the recoverable reserves of the two reservoirs, the production system used, capital costs of the project, and overall targets for Canadian benefit. Significant dates for the Hibernia project are listed. (UK)

  17. Ethanol Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  18. Fuels planning: science synthesis and integration; social issues fact sheet 12: Keys to successful collaboration

    Science.gov (United States)

    Christine Esposito

    2006-01-01

    Collaborating on fire and fuels management with a host of public and private partners may seem like an impossible undertaking, and presents many challenges. This fact sheet reviews tips for what to focus on as you embark on a collaborative fuels management project.Other...

  19. Tips for Postpartum Dads and Partners

    Science.gov (United States)

    ... Blues: Partners Interview with Wade Bowen Coping with Suicide & Loss Tips for Postpartum Dads and Partners Pregnancy and postpartum mood and anxiety disorders affect the whole family. Here are some tips ...

  20. Tips for Reducing Pesticide Impacts on Wildlife

    Science.gov (United States)

    This Web page provides tips for pesticide users in residential and agricultural settings, as well as tips for certified pesticide applicators for ways to protect wildlife from potentially harmful effects of pesticides.

  1. Rubella - Fact Sheet for Parents

    Science.gov (United States)

    ... and 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Rubéola The best way ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

  2. Changes in Greenland ice bed conditions inferred from seismology

    Science.gov (United States)

    Toyokuni, Genti; Takenaka, Hiroshi; Takagi, Ryota; Kanao, Masaki; Tsuboi, Seiji; Tono, Yoko; Childs, Dean; Zhao, Dapeng

    2018-04-01

    Basal conditions of the Greenland Ice Sheet (GrIS) are a key research topic in climate change studies. The recent construction of a seismic network has provided a new opportunity for direct, real-time, and continuous monitoring of the GrIS. Here we use ambient noise surface wave data from seismic stations all over Greenland for a 4.5-year period to detect changes in Rayleigh-wave phase velocity between seismic station pairs. We observe clear seasonal and long-term velocity changes for many pairs, and propose a plausible mechanism for these changes. Dominant factors driving the velocity changes might be seasonal and long-term pressurization/depressurization of the GrIS and shallow bedrock by air and ice mass loading/unloading. However, heterogeneity of the GrIS basal conditions might impose strong regionalities on the results. An interesting feature is that, even at adjacent two station pairs in the inland GrIS, one pair shows velocity decrease while another shows velocity increase as a response to the high air and snow pressure. The former pair might be located on a thawed bed that decreases velocity by increased meltwater due to pressure melting, whereas the latter pair might be located on a frozen bed that increases velocity by compaction of ice and shallow bedrock. The results suggest that surface waves are very sensitive to the GrIS basal conditions, and further observations will contribute to a more direct and quantitative estimation of water balance in the Arctic region.

  3. Sound source location in cavitating tip vortices

    International Nuclear Information System (INIS)

    Higuchi, H.; Taghavi, R.; Arndt, R.E.A.

    1985-01-01

    Utilizing an array of three hydrophones, individual cavitation bursts in a tip vortex could be located. Theoretically, four hydrophones are necessary. Hence the data from three hydrophones are supplemented with photographic observation of the cavitating tip vortex. The cavitation sound sources are found to be localized to within one base chord length from the hydrofoil tip. This appears to correspond to the region of initial tip vortex roll-up. A more extensive study with a four sensor array is now in progress

  4. Radiofrequency Wire Recanalization of Chronically Thrombosed TIPS

    Energy Technology Data Exchange (ETDEWEB)

    Majdalany, Bill S., E-mail: bmajdala@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States); Elliott, Eric D., E-mail: eric.elliott@osumc.edu [The Ohio State University Wexner Medical Center, Division of Interventional Radiology, Department of Radiology (United States); Michaels, Anthony J., E-mail: Anthony.michaels@osumc.edu; Hanje, A. James, E-mail: James.Hanje@osumc.edu [The Ohio State University Wexner Medical Center, Division of Gastroenterology and Hepatology, Department of Medicine (United States); Saad, Wael E. A., E-mail: wsaad@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States)

    2016-07-15

    Radiofrequency (RF) guide wires have been applied to cardiac interventions, recanalization of central venous thromboses, and to cross biliary occlusions. Herein, the use of a RF wire technique to revise chronically occluded transjugular intrahepatic portosystemic shunts (TIPS) is described. In both cases, conventional TIPS revision techniques failed to revise the chronically thrombosed TIPS. RF wire recanalization was successfully performed through each of the chronically thrombosed TIPS, demonstrating initial safety and feasibility in this application.

  5. Injector tip for an internal combustion engine

    Science.gov (United States)

    Shyu, Tsu Pin; Ye, Wen

    2003-05-20

    This invention relates to a the tip structure of a fuel injector as used in a internal combustion engine. Internal combustion engines using Homogeneous Charge Compression Ignition (HCCI) technology require a tip structure that directs fuel spray in a downward direction. This requirement necessitates a tip design that is capable of withstanding mechanical stresses associated with the design.

  6. CURRENT SHEET ENERGETICS, FLARE EMISSIONS, AND ENERGY PARTITION IN A SIMULATED SOLAR ERUPTION

    International Nuclear Information System (INIS)

    Reeves, Katharine K.; Linker, Jon A.; Mikic, Zoran; Forbes, Terry G.

    2010-01-01

    We investigate coronal energy flow during a simulated coronal mass ejection (CME). We model the CME in the context of the global corona using a 2.5D numerical MHD code in spherical coordinates that includes coronal heating, thermal conduction, and radiative cooling in the energy equation. The simulation domain extends from 1 to 20 R s . To our knowledge, this is the first attempt to apply detailed energy diagnostics in a flare/CME simulation when these important terms are considered in the context of the MHD equations. We find that the energy conservation properties of the code are quite good, conserving energy to within 4% for the entire simulation (more than 6 days of real time). We examine the energy release in the current sheet as the eruption takes place, and find, as expected, that the Poynting flux is the dominant carrier of energy into the current sheet. However, there is a significant flow of energy out of the sides of the current sheet into the upstream region due to thermal conduction along field lines and viscous drag. This energy outflow is spatially partitioned into three separate components, namely, the energy flux flowing out the sides of the current sheet, the energy flowing out the lower tip of the current sheet, and the energy flowing out the upper tip of the current sheet. The energy flow through the lower tip of the current sheet is the energy available for heating of the flare loops. We examine the simulated flare emissions and energetics due to the modeled CME and find reasonable agreement with flare loop morphologies and energy partitioning in observed solar eruptions. The simulation also provides an explanation for coronal dimming during eruptions and predicts that the structures surrounding the current sheet are visible in X-ray observations.

  7. Film sheet cassette

    International Nuclear Information System (INIS)

    1981-01-01

    A novel film sheet cassette is described for handling CAT photographic films under daylight conditions and facilitating their imaging. A detailed description of the design and operation of the cassette is given together with appropriate illustrations. The resulting cassette is a low-cost unit which is easily constructed and yet provides a sure light-tight seal for the interior contents of the cassette. The individual resilient fingers on the light-trap permit the ready removal of the slide plate for taking pictures. The stippled, non-electrostatic surface of the pressure plate ensures an air layer and free slidability of the film for removal and withdrawal of the film sheet. The advantage of the daylight system is that a darkroom need not be used for inserting and removing the film in and out of the cassette resulting in a considerable time saving. (U.K.)

  8. Clean Cities Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    2004-01-01

    This fact sheet explains the Clean Cities Program and provides contact information for all coalitions and regional offices. It answers key questions such as: What is the Clean Cities Program? What are alternative fuels? How does the Clean Cities Program work? What sort of assistance does Clean Cities offer? What has Clean Cities accomplished? What is Clean Cities International? and Where can I find more information?

  9. Information sheets on energy

    International Nuclear Information System (INIS)

    2004-01-01

    These sheets, presented by the Cea, bring some information, in the energy domain, on the following topics: the world energy demand and the energy policy in France and in Europe, the part of the nuclear power in the energy of the future, the greenhouse gases emissions and the fight against the greenhouse effect, the carbon dioxide storage cost and the hydrogen economy. (A.L.B.)

  10. Biomolecular Science (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-04-01

    A brief fact sheet about NREL Photobiology and Biomolecular Science. The research goal of NREL's Biomolecular Science is to enable cost-competitive advanced lignocellulosic biofuels production by understanding the science critical for overcoming biomass recalcitrance and developing new product and product intermediate pathways. NREL's Photobiology focuses on understanding the capture of solar energy in photosynthetic systems and its use in converting carbon dioxide and water directly into hydrogen and advanced biofuels.

  11. Sheet pinch devices

    International Nuclear Information System (INIS)

    Anderson, O.A.; Baker, W.R.; Ise, J. Jr.; Kunkel, W.B.; Pyle, R.V.; Stone, J.M.

    1958-01-01

    Three types of sheet-like discharges are being studied at Berkeley. The first of these, which has been given the name 'Triax', consists of a cylindrical plasma sleeve contained between two coaxial conducting cylinders A theoretical analysis of the stability of the cylindrical sheet plasma predicts the existence of a 'sausage-mode' instability which is, however, expected to grow more slowly than in the case of the unstabilized linear pinch (by the ratio of the radial dimensions). The second pinch device employs a disk shaped discharge with radial current guided between flat metal plates, this configuration being identical to that of the flat hydromagnetic capacitor without external magnetic field. A significant feature of these configurations is the absence of a plasma edge, i.e., there are no regions of sharply curved magnetic field lines anywhere in these discharges. The importance of this fact for stability is not yet fully investigated theoretically. As a third configuration a rectangular, flat pinch tube has been constructed, and the behaviour of a flat plasma sheet with edges is being studied experimentally

  12. Mobile and modular. BGR develops seismological monitoring stations for universal applications; Mobil und modular. BGR entwickelt universell einsetzbare seismologische Messstationen

    Energy Technology Data Exchange (ETDEWEB)

    Hinz, Erwin; Hanneken, Mark [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany). Fachbereich ' ' Seismologisches Zentralobservatorium, Kernwaffenteststopp' '

    2016-05-15

    BGR seismologists often set up monitoring stations for testing purposes. The engineers from the Central Seismological Observatory have now developed a new type of mobile monitoring station which can be remotely controlled.

  13. Study of seismological evasion. Part III. Evaluation of evasion possibilities using codas of large earthquakes

    International Nuclear Information System (INIS)

    Evernden, J.F.

    1976-01-01

    The seismological aspects of various proposed means of obscuring or hiding the seismic signatures of explosions from a surveillance network are discussed. These so-called evasion schemes are discussed from the points of view of both the evader and the monitor. The analysis will be conducted in terms of the USSR solely because that country is so vast and the geological/geophysical complexities of the country are so great that the complete spectrum of hypothesized evasion schemes requires discussion. Techniques appropriate for use when the seismic noise problem is interference due to codas of P and surface waves from earthquakes are described, and the capabilities of several seismological networks to restrain use of such codas for effective evasion are analyzed

  14. Research and development activities of the Seismology Section for the period January 1984 - December 1985

    International Nuclear Information System (INIS)

    Krishnan, C.A.; Murty, G.S.

    1987-01-01

    The Research and Development (R and D) activities during 1984-1985 of the Seismology Section of the Bhabha Atomic Research Centre, Bombay are reported in the form of individual summaries. The R and D activities of the Section are directed towards development of seismological instruments and methods of analysis of the seismic field data with the main objective of detecting underground nuclear explosions and assessing seismicity and seismic risk of sites considered for nuclear power stations. The Section has two field stations - one at Gauribidanur in the Southern part of the country and another at Delhi i.e. in the northern part of the country. During the report period, a total of 62 events out of the detected ones were identified as underground explosions. The expertise of the Section is also made available for outside organisations. (M.G.B.)

  15. Seismology, 1983, nuclear test ban verification earthquake and earth resource investigation

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-01

    This progress report for 1983 is the fourth yearly report summarizing the activities of the Division of Applied Seismology of the National Defence Research Institute (FOA) in Sweden. This division of the Institute is mainly involved in seismic discrimination and nuclear explosion monitoring. Special attention is paid in this report to the development of International Data Centers as a component of a global monitoring system. The division is also conducting a project on seismic risk estimation at nuclear power plants in Sweden. This project includes operating a network of local seismic stations in Sweden. Two seismic exploration projects are also currently being conducted. One project involves the further development of seismic methods for oil exploration, and the other the investigation of crystalline rock using seismic cross hole measurement. Finally the Division of Applied Seismology is conducting a project where seismic sensor in military applications are studied.

  16. Seismology: Ways and means for regional cooperation. Transparencies used during the presentation

    International Nuclear Information System (INIS)

    Menzhi, M.

    1999-01-01

    Within the frame of international cooperation in the field of CTBT, this paper describes the first seismologic station established in Morocco in 1934, and in sixties and seventies another 15 stations after the earthquake in Agadir. In 1982, a system for seismic detection was installed having as main objectives he following: coordination and correlation of activities concerned with evaluation of seismic risks in the Mediterranean region, and integration of geophysical data needed for seismic risk assessment

  17. Reflections from the interface between seismological research and earthquake risk reduction

    Science.gov (United States)

    Sargeant, S.

    2012-04-01

    Scientific understanding of earthquakes and their attendant hazards is vital for the development of effective earthquake risk reduction strategies. Within the global disaster reduction policy framework (the Hyogo Framework for Action, overseen by the UN International Strategy for Disaster Reduction), the anticipated role of science and scientists is clear, with respect to risk assessment, loss estimation, space-based observation, early warning and forecasting. The importance of information sharing and cooperation, cross-disciplinary networks and developing technical and institutional capacity for effective disaster management is also highlighted. In practice, the degree to which seismological information is successfully delivered to and applied by individuals, groups or organisations working to manage or reduce the risk from earthquakes is variable. The challenge for scientists is to provide fit-for-purpose information that can be integrated simply into decision-making and risk reduction activities at all levels of governance and at different geographic scales, often by a non-technical audience (i.e. people without any seismological/earthquake engineering training). The interface between seismological research and earthquake risk reduction (defined here in terms of both the relationship between the science and its application, and the scientist and other risk stakeholders) is complex. This complexity is a function of a range issues that arise relating to communication, multidisciplinary working, politics, organisational practices, inter-organisational collaboration, working practices, sectoral cultures, individual and organisational values, worldviews and expectations. These factors can present significant obstacles to scientific information being incorporated into the decision-making process. The purpose of this paper is to present some personal reflections on the nature of the interface between the worlds of seismological research and risk reduction, and the

  18. Antarctic ice sheet thickness estimation based on P-receiver function and waveform inversion

    Science.gov (United States)

    Yan, P.; Li, F.; LI, Z.; Li, J.; Yang, Y.; Hao, W.

    2016-12-01

    Antarctic ice sheet thickness is key parameter and boundary condition for ice sheet model construction, which has great significance for glacial isostatic adjustment, ice sheet mass balance and global change study. Ice thickness acquired utilizing seismological receiver function method can complement and verify with results obtained by radar echo sounding method. In this paper, P-receiver functions(PRFs) are extracted for stations deployed on Antarctic ice sheet, then Vp/Vs ratio and ice thickness are obtained using H-Kappa stacking. Comparisons are made between Bedmap2 dataset and the ice thickness from PRFs, most of the absolute value of the differences are less than 200 meters, only a few reach 600 meters. Taking into account of the intensity of Bedmap2 dataset survey lines and the uncertainty of radio echo sounding, as well as the inherit complexity of the internal ice structure beneath some stations, the ice thickness obtained from receiver function method is reliable. However limitation exists when using H-Kappa stacking method for stations where sediment squeezed between the ice and the bed rock layer. For better verifying the PRF result, a global optimizing method-Neighbourhood algotithm(NA) and spline interpolation are used to modeling PRFs assuming an isotropic layered ice sheet with depth varied densities and velocities beneath the stations. Then the velocity structure and ice sheet thickness are obtained through nonlinear searching by optimally fitting the real and the theoretical PRFs. The obtained ice sheet thickness beneath the stations agree well with the former H-Kappa method, but further detailed study are needed to constrain the inner ice velocity structure.

  19. Dense sheet Z-pinches

    International Nuclear Information System (INIS)

    Tetsu, Miyamoto

    1999-01-01

    The steady state and quasi-steady processes of infinite- and finite-width sheet z-pinches are studied. The relations corresponding to the Bennett relation and Pease-Braginskii current of cylindrical fiber z-pinches depend on a geometrical factor in the sheet z-pinches. The finite-width sheet z-pinch is approximated by a segment of infinite-width sheet z-pinch, if it is wide enough, and corresponds to a number of (width/thickness) times fiber z-pinch plasmas of the diameter that equals the sheet thickness. If the sheet current equals this number times the fiber current, the plasma created in the sheet z-pinches is as dense as in the fiber z-pinches. The total energy of plasma and magnetic field per unit mass is approximately equal in both pinches. Quasi-static transient processes are different in several aspects from the fiber z-pinch. No radiation collapse occurs in the sheet z-pinch. The stability is improved in the sheet z-pinches. The fusion criterions and the experimental arrangements to produce the sheet z-pinches are also discussed. (author)

  20. Local measurement and numerical modeling of mass/heat transfer from a turbine blade in a linear cascade with tip clearance

    Science.gov (United States)

    Jin, Peitong

    2000-11-01

    Local mass/heat transfer measurements from the turbine blade near-tip and the tip surfaces are performed using the naphthalene sublimation technique. The experiments are conducted in a linear cascade consisting of five high-pressure blades with a central test-blade configuration. The incoming flow conditions are close to those of the gas turbine engine environment (boundary layer displacement thickness is about 0.01 of chord) with an exit Reynolds number of 6.2 x 105. The effects of tip clearance level (0.86%--6.90% of chord), mainstream Reynolds number and turbulence intensity (0.2 and 12.0%) are investigated. Two methods of flow visualization---oil and lampblack, laser light sheet smoke wire---as well as static pressure measurement on the blade surface are used to study the tip leakage flow and vortex in the cascade. In addition, numerical modeling of the flow and heat transfer processes in the linear cascade with different tip clearances is conducted using commercial software incorporating advanced turbulence models. The present study confirms many important results on the tip leakage flow and vortex from the literature, contributes to the current understanding in the effects of tip leakage flow and vortex on local heat transfer from the blade near-tip and the tip surfaces, and provides detailed local and average heat/mass transfer data applicable to turbine blade tip cooling design.

  1. Twitter Tips, Tricks, and Tweets

    CERN Document Server

    McFedries, Paul

    2010-01-01

    Maximize your fun and boost your productivity with this updated, full-color guide to tantalizing Twitter tips!. The popularity of Twitter continues to soar, and is fast becoming the most popular social networking site online. Whether you're looking to learn how to set up an account for the first time or are on the prowl for some cool third-party Twitter apps, this full-color guide will boost your entire Twitter experience. Allowing you to communicate with fellow Twitters within a 140-character limit, this fun and fascinating social networking tool is easier than maintaining a blog and quicker

  2. Windows 8 visual quick tips

    CERN Document Server

    McFedries, Paul

    2012-01-01

    Easy-in, easy-out format covers all the bells and whistles of Windows 8 If you want to learn how to work smarter and faster in Microsoft's Windows 8 operating system, this easy-to-use, compact guide delivers the goods. Designed for visual learners, it features short explanations and full-color screen shots on almost every page, and it's packed with timesaving tips and helpful productivity tricks. From enhancing performance and managing digital content to setting up security and much more, this handy guide will help you get more out of Windows 8. Uses full-color screen shots and short, step-by-

  3. Perforation of metal sheets

    DEFF Research Database (Denmark)

    Steenstrup, Jens Erik

    simulation is focused on the sheet deformation. However, the effect on the tool and press is included. The process model is based on the upper bound analysis in order to predict the force progress and hole characteristics etc. Parameter analyses are divided into two groups, simulation and experimental tests......The main purposes of this project are:1. Development of a dynamic model for the piercing and performation process2. Analyses of the main parameters3. Establishing demands for process improvements4. Expansion of the existing parameter limitsThe literature survey describes the process influence...

  4. SeisCode: A seismological software repository for discovery and collaboration

    Science.gov (United States)

    Trabant, C.; Reyes, C. G.; Clark, A.; Karstens, R.

    2012-12-01

    SeisCode is a community repository for software used in seismological and related fields. The repository is intended to increase discoverability of such software and to provide a long-term home for software projects. Other places exist where seismological software may be found, but none meet the requirements necessary for an always current, easy to search, well documented, and citable resource for projects. Organizations such as IRIS, ORFEUS, and the USGS have websites with lists of available or contributed seismological software. Since the authors themselves do often not maintain these lists, the documentation often consists of a sentence or paragraph, and the available software may be outdated. Repositories such as GoogleCode and SourceForge, which are directly maintained by the authors, provide version control and issue tracking but do not provide a unified way of locating geophysical software scattered in and among countless unrelated projects. Additionally, projects are hosted at language-specific sites such as Mathworks and PyPI, in FTP directories, and in websites strewn across the Web. Search engines are only partially effective discovery tools, as the desired software is often hidden deep within the results. SeisCode provides software authors a place to present their software, codes, scripts, tutorials, and examples to the seismological community. Authors can choose their own level of involvement. At one end of the spectrum, the author might simply create a web page that points to an existing site. At the other extreme, an author may choose to leverage the many tools provided by SeisCode, such as a source code management tool with integrated issue tracking, forums, news feeds, downloads, wikis, and more. For software development projects with multiple authors, SeisCode can also be used as a central site for collaboration. SeisCode provides the community with an easy way to discover software, while providing authors a way to build a community around their

  5. The art of communicating seismology to broad audiences: the exhibition which changed the perception

    Science.gov (United States)

    Toma-Danila, Dragos; Tataru, Dragos; Nastase, Eduard; Muntean, Alexandra; Partheniu, Raluca

    2017-04-01

    Seismology is a geoscience often perceived by uninstructed broad audiences as unreliable or inconsistent, since it cannot predict future earthquakes or warn about them effectively; this criticism disregards important achievements that seismology has offered during its more than 100 years of history - such as evidence of Earth's inner structure, knowledge regarding plate tectonics, mineral resource identification, contributions to risk mitigation, monitoring of explosions etc. Moreover, seismology is a field of study with significant advances, which make (or could make) living much safer, in areas with high seismic hazard. We mentioned "could make" since people often fail to understand an important aspect: seismology offers consistent knowledge regarding how to prepare, construct or behave - but it's up to people and authorities to implement the effective measures. In all this story, the effective communication between scientists and the general public plays a major role, making the leap from misconception to relevant impact. As scientists, we wanted to show the true meaning and purpose of seismology to all categories of people. We are in the final stage of the MOBEE (MOBile Earthquake Exhibition) Project implementation, an innovative initiative in a highly seismic country (Romania), where major Vrancea intermediate-depth earthquakes source have the potential to generate a significant amount of damage over large areas; however, unlike countries like Japan, the medium to long period between felt or significant events (20-40 years) is long enough to make the newer generation in Romania disregardful of the hazard, and older generations skeptical about the role of seismology. MOBEE intended to freshen up things, raise awareness and change the overall perception - through new approaches involving a blend of digital content (interactive apps, responsive and continuously updated website), 3D models achieved through new technologies (3D printing, fiber optics), non

  6. Experiments on sheet metal shearing

    OpenAIRE

    Gustafsson, Emil

    2013-01-01

    Within the sheet metal industry, different shear cutting technologies are commonly used in several processing steps, e.g. in cut to length lines, slitting lines, end cropping etc. Shearing has speed and cost advantages over competing cutting methods like laser and plasma cutting, but involves large forces on the equipment and large strains in the sheet material.Numerical models to predict forces and sheared edge geometry for different sheet metal grades and different shear parameter set-ups a...

  7. Towards easy and reliable AFM tip shape determination using blind tip reconstruction

    International Nuclear Information System (INIS)

    Flater, Erin E.; Zacharakis-Jutz, George E.; Dumba, Braulio G.; White, Isaac A.; Clifford, Charles A.

    2014-01-01

    Quantitative determination of the geometry of an atomic force microscope (AFM) probe tip is critical for robust measurements of the nanoscale properties of surfaces, including accurate measurement of sample features and quantification of tribological characteristics. Blind tip reconstruction, which determines tip shape from an AFM image scan without knowledge of tip or sample shape, was established most notably by Villarrubia [J. Res. Natl. Inst. Stand. Tech. 102 (1997)] and has been further developed since that time. Nevertheless, the implementation of blind tip reconstruction for the general user to produce reliable and consistent estimates of tip shape has been hindered due to ambiguity about how to choose the key input parameters, such as tip matrix size and threshold value, which strongly impact the results of the tip reconstruction. These key parameters are investigated here via Villarrubia's blind tip reconstruction algorithms in which we have added the capability for users to systematically vary the key tip reconstruction parameters, evaluate the set of possible tip reconstructions, and determine the optimal tip reconstruction for a given sample. We demonstrate the capabilities of these algorithms through analysis of a set of simulated AFM images and provide practical guidelines for users of the blind tip reconstruction method. We present a reliable method to choose the threshold parameter corresponding to an optimal reconstructed tip shape for a given image. Specifically, we show that the trend in how the reconstructed tip shape varies with threshold number is so regular that the optimal, or Goldilocks, threshold value corresponds with the peak in the derivative of the RMS difference with respect to the zero threshold curve vs. threshold number. - Highlights: • Blind tip reconstruction algorithms have been implemented and augmented to determine the optimal input parameters. • We demonstrate the capabilities of the algorithms using a simulated AFM

  8. Influence of the tip mass on the tip-sample interactions in TM-AFM

    Energy Technology Data Exchange (ETDEWEB)

    Pishkenari, Hossein Nejat, E-mail: nejat@mech.sharif.edu [Nano-Robotics Laboratory, Center of Excellence in Design, Robotics and Automation, School of Mechanical Engineering, Sharif University of Technology, Tehran, P.O. Box 11365-9465 (Iran, Islamic Republic of); Meghdari, Ali [Nano-Robotics Laboratory, Center of Excellence in Design, Robotics and Automation, School of Mechanical Engineering, Sharif University of Technology, Tehran, P.O. Box 11365-9465 (Iran, Islamic Republic of)

    2011-07-15

    This paper focuses on the influences of the tip mass ratio (the ratio of the tip mass to the cantilever mass), on the excitation of higher oscillation eigenmodes and also on the tip-sample interaction forces in tapping mode atomic force microscopy (TM-AFM). A precise model for the cantilever dynamics capable of accurate simulations is essential for the investigation of the tip mass effects on the interaction forces. In the present work, the finite element method (FEM) is used for modeling the AFM cantilever to consider the oscillations of higher eigenmodes oscillations. In addition, molecular dynamics (MD) is used to calculate precise data for the tip-sample force as a function of tip vertical position with respect to the sample. The results demonstrate that in the presence of nonlinear tip-sample interaction forces, the tip mass ratio plays a significant role in the excitations of higher eigenmodes and also in the normal force applied on the surface. Furthermore, it has been shown that the difference between responses of the FEM and point-mass models in different system operational conditions is highly affected by the tip mass ratio. -- Highlights: {yields} A strong correlation exists between the tip mass ratio and the 18th harmonic amplitude. {yields} Near the critical tip mass ratio a small change in the tip mass may lead to a significant force change. {yields} Inaccuracy of the lumped model depends significantly on the tip mass ratio.

  9. Tip Clearance Control Using Plasma Actuators

    Science.gov (United States)

    2007-03-01

    Clearance Control Using Plasma Actuators 4 posed by Denton (1993). A number of investigators have used partial shrouds, or " winglet " designs to...SDBD actuator Plasma enhanced aerodynamics has been demonstrated in a range of applications involving sepa- ration control, lift enhancement, drag... aerodynamic benefits of a squealer tip geometry. Specifically, the squealer tip is known to reduce the discharge coefficient of the tip gap, thereby

  10. Numerical investigation of tip leakage vortex

    OpenAIRE

    Fredriksen, Vegard

    2017-01-01

    The Kaplan turbine has a small clearance gap between the blade tip and casing to allow the blades to rotate freely. This clearance gap is the cause of an undesirable Tip Leakage Vortex (TLV). A TLV might reduce the turbine efficiency, erode the turbine blades or cause instabilities for the power output. A literature study indicated that the tip clearance gap was a critical parameter affecting the behavior of the TLV. A research gap was observed for an operating Kaplan turbine where the ...

  11. RANS computations of tip vortex cavitation

    Science.gov (United States)

    Decaix, Jean; Balarac, Guillaume; Dreyer, Matthieu; Farhat, Mohamed; Münch, Cécile

    2015-12-01

    The present study is related to the development of the tip vortex cavitation in Kaplan turbines. The investigation is carried out on a simplified test case consisting of a NACA0009 blade with a gap between the blade tip and the side wall. Computations with and without cavitation are performed using a R ANS modelling and a transport equation for the liquid volume fraction. Compared with experimental data, the R ANS computations turn out to be able to capture accurately the development of the tip vortex. The simulations have also highlighted the influence of cavitation on the tip vortex trajectory.

  12. Direct calculation of wind turbine tip loss

    DEFF Research Database (Denmark)

    Wood, D.H.; Okulov, Valery; Bhattacharjee, D.

    2016-01-01

    . We develop three methods for the direct calculation of the tip loss. The first is the computationally expensive calculation of the velocities induced by the helicoidal wake which requires the evaluation of infinite sums of products of Bessel functions. The second uses the asymptotic evaluation......The usual method to account for a finite number of blades in blade element calculations of wind turbine performance is through a tip loss factor. Most analyses use the tip loss approximation due to Prandtl which is easily and cheaply calculated but is known to be inaccurate at low tip speed ratio...

  13. Study on unsteady tip leakage vortex cavitation in an axial-flow pump using an improved filter-based model

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Desheng; Shi, Lei; Zhao, Ruijie; Shi, Weidong; Pan, Qiang [Jiangsu University, Zhenjiang (China); Esch, B. P. [Eindhoven University of Technology, Eindhoven (Netherlands)

    2017-02-15

    The aim of the present investigation is to simulate and analyze the tip leakage flow structure and instantaneous evolution of tip vortex cavitation in a scaled axial-flow pump model. The improved filter-based turbulence model based on the density correction and a homogeneous cavitation model were used for implementing this work. The results show that when entering into the tip clearance, the backward flow separates from the blade tip near the pressure side, resulting in the generation of a corner vortex with high magnitude of turbulence kinetic energy. Then, at the exit of the tip clearance, the leakage jets would re-attach on the blade tip wall. Moreover, the maximum swirling strength method was employed in identifying the TLV core and a counter-rotating induced vortex near the end-wall successfully. The three dimensional cavitation patterns and in-plain cavitation structures obtained by the improved numerical method agree well with the experimental results. At the sheet cavitation trailing edge in the tip region, the perpendicular cavitation cloud induced by TLV sheds and migrates toward the pressure side of the neighboring blade. During its migration, it breaks down abruptly and generates a large number of smallscale cavities, leading to severe degradation of the pump performance, which is similar with the phenomenon observed by Tan et al.

  14. Soft Costs Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-05-01

    This fact sheet is an overview of the systems integration subprogram at the U.S. Department of Energy SunShot Initiative. Soft costs can vary significantly as a result of a fragmented energy marketplace. In the U.S., there are 18,000 jurisdictions and 3,000 utilities with different rules and regulations for how to go solar. The same solar equipment may vary widely in its final installation price due to process and market variations across jurisdictions, creating barriers to rapid industry growth. SunShot supports the development of innovative solutions that enable communities to build their local economies and establish clean energy initiatives that meet their needs, while at the same time creating sustainable solar market conditions.

  15. Photovoltaics Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-02-01

    This fact sheet is an overview of the Photovoltaics (PV) subprogram at the U.S. Department of Energy SunShot Initiative. The U.S. Department of Energy (DOE)’s Solar Energy Technologies Office works with industry, academia, national laboratories, and other government agencies to advance solar PV, which is the direct conversion of sunlight into electricity by a semiconductor, in support of the goals of the SunShot Initiative. SunShot supports research and development to aggressively advance PV technology by improving efficiency and reliability and lowering manufacturing costs. SunShot’s PV portfolio spans work from early-stage solar cell research through technology commercialization, including work on materials, processes, and device structure and characterization techniques.

  16. Systems Integration Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    This fact sheet is an overview of the Systems Integration subprogram at the U.S. Department of Energy SunShot Initiative. The Systems Integration subprogram enables the widespread deployment of safe, reliable, and cost-effective solar energy technologies by addressing the associated technical and non-technical challenges. These include timely and cost-effective interconnection procedures, optimal system planning, accurate prediction of solar resources, monitoring and control of solar power, maintaining grid reliability and stability, and many more. To address the challenges associated with interconnecting and integrating hundreds of gigawatts of solar power onto the electricity grid, the Systems Integration program funds research, development, and demonstration projects in four broad, interrelated focus areas: grid performance and reliability, dispatchability, power electronics, and communications.

  17. Hyperspectral light sheet microscopy

    Science.gov (United States)

    Jahr, Wiebke; Schmid, Benjamin; Schmied, Christopher; Fahrbach, Florian O.; Huisken, Jan

    2015-09-01

    To study the development and interactions of cells and tissues, multiple fluorescent markers need to be imaged efficiently in a single living organism. Instead of acquiring individual colours sequentially with filters, we created a platform based on line-scanning light sheet microscopy to record the entire spectrum for each pixel in a three-dimensional volume. We evaluated data sets with varying spectral sampling and determined the optimal channel width to be around 5 nm. With the help of these data sets, we show that our setup outperforms filter-based approaches with regard to image quality and discrimination of fluorophores. By spectral unmixing we resolved overlapping fluorophores with up to nanometre resolution and removed autofluorescence in zebrafish and fruit fly embryos.

  18. Evolution of the Concordia seismological observatory station CCD (GEOSCOPE network): a new post-hole installation on Antarctica inlandsis

    Science.gov (United States)

    Zigone, D.; Danecek, P.; Bès de Berc, M.; Maggi, A.; Thore, J. Y.; Leveque, J. J.; Vallee, M.; Bernard, A.; Sayadi, J.; Morelli, A.; Delladio, A.; Chappellaz, J. A.; Alemany, O.; Possenti, P.; Stutzmann, E.; Bonaime, S.; Pesqueira, F.; Pardo, C.; Vincent, D.

    2017-12-01

    Concordia (75°S 123°E) is a scientific base operated by French polar institute IPEV (Institut Paul-Emile Victor) and Italian Antarctic Program PNRA (Programma Nazionale di Ricerche in Antartide), and is located at Dome C, on the ice sheet of the East Antarctica plateau. It hosts a seismological observatory (CCD), which is jointly operated by EOST (Strasbourg) and INGV (Roma). The highly strategic location and remoteness is the key strength of our program, which has provided observatory quality data since 2000. The station has been integrated into the GEOSCOPE network in 2008 and the data are now available in real time through GEOSCOPE and IRIS. The observatory is located at distance of 1km from the base. The current installation is placed at a depth of 12m in an artificial vault constructed from two shipping containers and buried in the snow. The vault is thermally very stable, but the relatively close proximity to the base causes increased diurnal noise ( 40 dB) at frequencies above 1Hz, especially during the summer season. The uppermost 100 m thick firn (snow) layer forms a waveguide, where anthropic noise from the base is trapped and easily picked up by the seismometers (T240 and STS2). Another limitation comes from the hydrostatic pressure of the snow which is continuously deforming the metallic structures: we record container cracking events on the seismograms, and we see visual evidence of structural deformations inside the tunnel and the vault. We propose an evolution of the CCD station towards a post-hole installation. Placing a sensor at a depth of approximately 130 meters, will reduce noise from thermal effects, from tilting and from anthropogenic activity, because it would be located below the firn layer waveguide and the ice pinch-out depth. In order to operate the borehole station for several years, we intend to keep the hole open and the sensor accessible, while ensuring good coupling between the sensor and the surrounding hard ice. To achieve these

  19. Settlement during vibratory sheet piling

    NARCIS (Netherlands)

    Meijers, P.

    2007-01-01

    During vibratory sheet piling quite often the soil near the sheet pile wall will settle. In many cases this is not a problem. For situations with houses, pipelines, roads or railroads at relative short distance these settlements may not be acceptable. The purpose of the research described in this

  20. Facilitating open global data use in earthquake source modelling to improve geodetic and seismological approaches

    Science.gov (United States)

    Sudhaus, Henriette; Heimann, Sebastian; Steinberg, Andreas; Isken, Marius; Vasyura-Bathke, Hannes

    2017-04-01

    In the last few years impressive achievements have been made in improving inferences about earthquake sources by using InSAR (Interferometric Synthetic Aperture Radar) data. Several factors aided these developments. The open data basis of earthquake observations has expanded vastly with the two powerful Sentinel-1 SAR sensors up in space. Increasing computer power allows processing of large data sets for more detailed source models. Moreover, data inversion approaches for earthquake source inferences are becoming more advanced. By now data error propagation is widely implemented and the estimation of model uncertainties is a regular feature of reported optimum earthquake source models. Also, more regularly InSAR-derived surface displacements and seismological waveforms are combined, which requires finite rupture models instead of point-source approximations and layered medium models instead of homogeneous half-spaces. In other words the disciplinary differences in geodetic and seismological earthquake source modelling shrink towards common source-medium descriptions and a source near-field/far-field data point of view. We explore and facilitate the combination of InSAR-derived near-field static surface displacement maps and dynamic far-field seismological waveform data for global earthquake source inferences. We join in the community efforts with the particular goal to improve crustal earthquake source inferences in generally not well instrumented areas, where often only the global backbone observations of earthquakes are available provided by seismological broadband sensor networks and, since recently, by Sentinel-1 SAR acquisitions. We present our work on modelling standards for the combination of static and dynamic surface displacements in the source's near-field and far-field, e.g. on data and prediction error estimations as well as model uncertainty estimation. Rectangular dislocations and moment-tensor point sources are exchanged by simple planar finite

  1. Plasma dynamics in current sheets

    International Nuclear Information System (INIS)

    Bogdanov, S.Yu.; Drejden, G.V.; Kirij, N.P.; AN SSSR, Leningrad

    1992-01-01

    Plasma dynamics in successive stages of current sheet evolution is investigated on the base of analysis of time-spatial variations of electron density and electrodynamic force fields. Current sheet formation is realized in a two-dimensional magnetic field with zero line under the action of relatively small initial disturbances (linear regimes). It is established that in the limits of the formed sheet is concentrated dense (N e ∼= 10 16 cm -3 ) (T i ≥ 100 eV, bar-Z i ≥ 2) hot pressure of which is balanced by the magnetic action of electrodynamic forces is carried out both plasma compression in the sheet limits and the acceleration along the sheet surface from a middle to narrow side edges

  2. COST Action ES1401 TIDES: a European network on TIme DEpendent Seismology

    Science.gov (United States)

    Morelli, Andrea

    2016-04-01

    Using the full-length records of seismic events and background ambient noise, today seismology is going beyond still-life snapshots of the interior of the Earth, and look into time-dependent changes of its properties. Data availability has grown dramatically with the expansion of seismographic networks and data centers, so as to enable much more detailed and accurate analyses. COST Action ES1401 TIDES (TIme DEpendent Seismology; http://tides-cost.eu) aims at structuring the EU seismological community to enable development of data-intensive, time-dependent techniques for monitoring Earth active processes (e.g., earthquakes, volcanic eruptions, landslides, glacial earthquakes) as well as oil/gas reservoirs. The main structure of TIDES is organised around working groups on: Workflow integration of data and computing resources; Seismic interferometry and ambient noise; Forward problems and High-performance computing applications; Seismic tomography, full waveform inversion and uncertainties; Applications in the natural environment and industry. TIDES is an open network of European laboratories with complementary skills, and is organising a series of events - workshops and advanced training schools - as well as supporting short-duration scientific stays. The first advanced training school was held in Bertinoro (Italy) on June 2015, with attendance of about 100 participants from 20 European countries, was devoted to how to manage and model seismic data with modern tools. The next school, devoted to ambient noise, will be held in 2016 Portugal: the program will be announced at the time of this conference. TIDES will strengthen Europe's role in a critical field for natural hazards and natural resource management.

  3. How citizen seismology is transforming rapid public earthquake information and interactions between seismologists and society

    Science.gov (United States)

    Bossu, Rémy; Steed, Robert; Mazet-Roux, Gilles; Roussel, Fréderic; Caroline, Etivant

    2015-04-01

    Historical earthquakes are only known to us through written recollections and so seismologists have a long experience of interpreting the reports of eyewitnesses, explaining probably why seismology has been a pioneer in crowdsourcing and citizen science. Today, Internet has been transforming this situation; It can be considered as the digital nervous system comprising of digital veins and intertwined sensors that capture the pulse of our planet in near real-time. How can both seismology and public could benefit from this new monitoring system? This paper will present the strategy implemented at Euro-Mediterranean Seismological Centre (EMSC) to leverage this new nervous system to detect and diagnose the impact of earthquakes within minutes rather than hours and how it transformed information systems and interactions with the public. We will show how social network monitoring and flashcrowds (massive website traffic increases on EMSC website) are used to automatically detect felt earthquakes before seismic detections, how damaged areas can me mapped through concomitant loss of Internet sessions (visitors being disconnected) and the benefit of collecting felt reports and geolocated pictures to further constrain rapid impact assessment of global earthquakes. We will also describe how public expectations within tens of seconds of ground shaking are at the basis of improved diversified information tools which integrate this user generated contents. A special attention will be given to LastQuake, the most complex and sophisticated Twitter QuakeBot, smartphone application and browser add-on, which deals with the only earthquakes that matter for the public: the felt and damaging earthquakes. In conclusion we will demonstrate that eyewitnesses are today real time earthquake sensors and active actors of rapid earthquake information.

  4. Developing Federated Services within Seismology: IRIS' involvement in the CoopEUS Project

    Science.gov (United States)

    Ahern, T. K.; Trabant, C. M.; Stults, M.

    2014-12-01

    As a founding member of the CoopEUS initiative, IRIS Data Services has partnered with five data centers in Europe and the UC Berkeley (NCEDC) in the US to implement internationally standardized web services to access seismological data using identical methodologies. The International Federation of Digital Seismograph Networks (FDSN) holds commission status within IASPEI/IUGG and as such is the international body that governs data exchange formats and access protocols within seismology. The CoopEUS project involves IRIS and UNAVCO as part of the EarthScope project and the European collaborators are all members of the European Plate Observing System (EPOS). CoopEUS includes one work package that attempts to coordinate data access between EarthScope and EPOS facilities. IRIS has worked with its partners in the FDSN to develop and adopt three key international service standards within seismology. These include 1) fdsn-dataselect, a service that returns time series data in a variety of standard formats, 2) fdsn-station, a service that returns related metadata about a seismic station in stationXML format, and 3) fdsn-event, a service that returns information about earthquakes and other seismic events in QuakeML format. Currently the 5 European data centers supporting these services include the ORFEUS Data Centre in the Netherlands, the GFZ German Research Centre for Geosciences in Potsdam, Germany, ETH Zurich in Switzerland, INGV in Rome, Italy, and the RESIF Data Centre in Grenoble France. Presently these seven centres can all be accessed using standardized web services with identical service calls and returns results in standardized ways. IRIS is developing an IRIS federator that will allow a client to seamlessly access information across the federated centers. Details and current status of the IRIS Federator will be presented.

  5. QuakeML: XML for Seismological Data Exchange and Resource Metadata Description

    Science.gov (United States)

    Euchner, F.; Schorlemmer, D.; Becker, J.; Heinloo, A.; Kästli, P.; Saul, J.; Weber, B.; QuakeML Working Group

    2007-12-01

    QuakeML is an XML-based data exchange format for seismology that is under development. Current collaborators are from ETH, GFZ, USC, USGS, IRIS DMC, EMSC, ORFEUS, and ISTI. QuakeML development was motivated by the lack of a widely accepted and well-documented data format that is applicable to a broad range of fields in seismology. The development team brings together expertise from communities dealing with analysis and creation of earthquake catalogs, distribution of seismic bulletins, and real-time processing of seismic data. Efforts to merge QuakeML with existing XML dialects are under way. The first release of QuakeML will cover a basic description of seismic events including picks, arrivals, amplitudes, magnitudes, origins, focal mechanisms, and moment tensors. Further extensions are in progress or planned, e.g., for macroseismic information, location probability density functions, slip distributions, and ground motion information. The QuakeML language definition is supplemented by a concept to provide resource metadata and facilitate metadata exchange between distributed data providers. For that purpose, we introduce unique, location-independent identifiers of seismological resources. As an application of QuakeML, ETH Zurich currently develops a Python-based seismicity analysis toolkit as a contribution to CSEP (Collaboratory for the Study of Earthquake Predictability). We follow a collaborative and transparent development approach along the lines of the procedures of the World Wide Web Consortium (W3C). QuakeML currently is in working draft status. The standard description will be subjected to a public Request for Comments (RFC) process and eventually reach the status of a recommendation. QuakeML can be found at http://www.quakeml.org.

  6. QuakeML: status of the XML-based seismological data exchange format

    Directory of Open Access Journals (Sweden)

    Joachim Saul

    2011-04-01

    Full Text Available QuakeML is an XML-based data exchange standard for seismology that is in its fourth year of active community-driven development. Its development was motivated by the need to consolidate existing data formats for applications in statistical seismology, as well as setting a cutting-edge, community-agreed standard to foster interoperability of distributed infrastructures. The current release (version 1.2 is based on a public Request for Comments process and accounts for suggestions and comments provided by a broad international user community. QuakeML is designed as an umbrella schema under which several sub-packages are collected. The present scope of QuakeML 1.2 covers a basic description of seismic events including picks, arrivals, amplitudes, magnitudes, origins, focal mechanisms, and moment tensors. Work on additional packages (macroseismic information, ground motion, seismic inventory, and resource metadata has been started, but is at an early stage. Several applications based on the QuakeML data model have been created so far. Among these are earthquake catalog web services at the European Mediterranean Seismological Centre (EMSC, GNS Science, and the Southern California Earthquake Data Center (SCEDC, and QuakePy, an open-source Python-based seismicity analysis toolkit. Furthermore, QuakeML is being used in the SeisComP3 system from GFZ Potsdam, and in the Collaboratory for the Study of Earthquake Predictability (CSEP testing center installations, developed by Southern California Earthquake Center (SCEC. QuakeML is still under active and dynamic development. Further contributions from the community are crucial to its success and are highly welcome.

  7. 20 year IRIS: impact on seismological research at home and abroad

    Science.gov (United States)

    van der Hilst, R. D.

    2004-12-01

    : The positive impact of IRIS, through its programs (GSN, PASSCAL, DMS, EO) and its workshops, on seismological research and community building can hardly be overestimated. The Data Management System has been very successful in bringing data to users for research and education anywhere in the world; it enables routine, and in many cases real time, analysis of massive amounts of waveform data for a spectacularly diverse range of studies. (I will give examples of surface wave tomography and inverse scattering studies of the core mantle boundary.) The support that PASSCAL provides for the planning and execution of field campaigns allows seismologists to shift attention from operational issues to exciting science, and the required data dissemination through DMS does not only result in tremendously valuable data sets but also contributes to community building through (international) collaboration. Europe, Australia, and Asia also have rich histories of network and portable array seismometry, and in many areas the cumulative station density exceeds that of North America (even, perhaps, with USArray). Moreover, in some cases, such as the use of temporary, roving arrays of broad band seismometers, activities overseas may have preceded and inspired developments in the US. However, the absence of effective central systems for management and dissemination of quality-controlled data has left many unique historical and regional data sets underutilized. This situation is changing, however. As an example I will mention the NERIES initiative to build a better infrastructure for seismological research and education in Europe. Apart from providing an example, through international collaboration IRIS can continue to play an important role in the improvement of the global seismological infrastructure.

  8. A short history of Japanese historical seismology: past and the present

    Science.gov (United States)

    Matsu'ura, Ritsuko S.

    2017-12-01

    Since seismicity in Japan is fairly high, Japanese interest in historical seismicity can be traced back to the nineth century, only a few centuries after the formation of the ancient ruling state. A 1000 years later, 2 years earlier than the modern seismological society was founded, the research on historical seismology started in Japan in 1878. By the accumulation for the recent 140 years, the present Japanese seismologists can read many historical materials without reading cursive scripts. We have a convenient access to the historical information related to earthquakes, in the modern characters of 27,759 pages. We now have 214 epicenters of historical earthquakes from 599 ad to 1872. Among them, 134 events in the early modern period were assigned hypocentral depths and proper magnitudes. The intensity data of 8700 places by those events were estimated. These precise intensity data enabled us to compare the detailed source areas of pairs of repeated historical earthquakes, such as the 1703 Genroku earthquake with the 1923 Kanto earthquake, and the 1707 Hoei earthquake with the summation of the 1854 Ansei Tokai and Ansei Nankai earthquakes. It is revealed that the focal area of the former larger event cannot completely include those of the latter smaller earthquakes, although those were believed to be typical sets of characteristic interplate earthquakes at the Sagami trough and at the Nankai trough. Research on historical earthquakes is very important to assess the seismic hazard in the future. We still have one-fifth events of the early modern period to be analyzed in detail. The compilation of places experienced high intensities in the modern events is also necessary. For the ancient and medieval periods, many equivocal events are still left. The further advance of the interdisciplinary research on historical seismology is necessary.

  9. Seismological and Geodynamic Monitoring Network in the "javakheti" Test Zone in the Southern Caucasus

    Science.gov (United States)

    Arakelyan, A.; Babayan, H.; Karakhanyan, A.; Durgaryan, R.; Basilaia, G.; Sokhadze, G.; Bidzinashvili, G.

    2012-12-01

    The Javakheti Highland located in the border region between Armenia and Georgia (sharing a border with Turkey) is an area in the Southern Caucasus of young Holocene-Quaternary volcanism and a region with convergence of a number of active faults. Issues related to the geometry, kinematics and slip-rate of these faults and assessment of their seismic hazard remain unclear in part due to the fragmentary nature of the studies carried out soley within the borders of each of the countries as opposed to region wide. In the frame of the ISTC A-1418 Project "Open network of scientific Centers for mitigation risk of natural hazards in the Southern Caucasus and Central Asia" the Javakheti Highland was selected as a trans-border test-zone. This designation allowed for the expansion and upgrading of the seismological and geodynamic monitoring networks under the auspices of several international projects (ISTC CSP-053 Project "Development of Communication System for seismic hazard situations in the Southern Caucasus and Central Asia", NATO SfP- 983284 Project "Caucasus Seismic Emergency Response") as well as through joint research programs with the National Taiwan University and Institute of Earth Sciences (IES, Taiwan), Universite Montpellier II (France) and Ecole et Observatoire des Sciences de la Terre-Université de Strasbourg (France). Studies of geodynamic processes, and seismicity of the region and their interaction have been carried out utilizing the newly established seismological and geodynamic monitoring networks and have served as a basis for the study of the geologic and tectonic structure . Upgrading and expansion of seismological and geodynamic networks required urgent solutions to the following tasks: Introduction of efficient online systems for information acquisition, accumulation and transmission (including sattelite systems) from permanent and temporary installed stations, Adoption of international standards for organization and management of databases in GIS

  10. Prediction of the area affected by earthquake-induced landsliding based on seismological parameters

    Science.gov (United States)

    Marc, Odin; Meunier, Patrick; Hovius, Niels

    2017-07-01

    We present an analytical, seismologically consistent expression for the surface area of the region within which most landslides triggered by an earthquake are located (landslide distribution area). This expression is based on scaling laws relating seismic moment, source depth, and focal mechanism with ground shaking and fault rupture length and assumes a globally constant threshold of acceleration for onset of systematic mass wasting. The seismological assumptions are identical to those recently used to propose a seismologically consistent expression for the total volume and area of landslides triggered by an earthquake. To test the accuracy of the model we gathered geophysical information and estimates of the landslide distribution area for 83 earthquakes. To reduce uncertainties and inconsistencies in the estimation of the landslide distribution area, we propose an objective definition based on the shortest distance from the seismic wave emission line containing 95 % of the total landslide area. Without any empirical calibration the model explains 56 % of the variance in our dataset, and predicts 35 to 49 out of 83 cases within a factor of 2, depending on how we account for uncertainties on the seismic source depth. For most cases with comprehensive landslide inventories we show that our prediction compares well with the smallest region around the fault containing 95 % of the total landslide area. Aspects ignored by the model that could explain the residuals include local variations of the threshold of acceleration and processes modulating the surface ground shaking, such as the distribution of seismic energy release on the fault plane, the dynamic stress drop, and rupture directivity. Nevertheless, its simplicity and first-order accuracy suggest that the model can yield plausible and useful estimates of the landslide distribution area in near-real time, with earthquake parameters issued by standard detection routines.

  11. Crack Tip Mechanics in Distortion Gradient Plasticity

    DEFF Research Database (Denmark)

    Fuentes-Alonso, Sandra; Martínez Pañeda, Emilio

    2017-01-01

    Gradient Plasticity (DGP), the influence on crack tip mechanics of DGP's distinguishing features that entail superior modelling capabilities has not been investigated yet. In this work crack tip fields are thoroughly examined by implementing the higher order theory of DGP in an implicit finite element...

  12. Jagged gives endothelial tip cells an edge.

    Science.gov (United States)

    Suchting, Steven; Eichmann, Anne

    2009-06-12

    Sprouting blood vessels have tip cells that lead and stalk cells that follow. Benedito et al. (2009) now show that competition between endothelial cells for the tip position is regulated by glycosylation of Notch receptors and by the opposing actions of the Notch ligands Jagged1 and Delta-like 4.

  13. Twelve Tips for Effective Electronic Presentation.

    Science.gov (United States)

    Crosby, Joy

    1994-01-01

    Offers 12 tips for effective electronic presentation. This article is intended for readers who may be considering using electronic presentation for the first time. Offers reasons for its popularity and occasions when it may be used. The tips offer assistance in the design and presentation of electronic material. (LZ)

  14. Recent advance in polar seismology: Global impact of the International Polar Year

    Science.gov (United States)

    Kanao, Masaki; Zhao, Dapeng; Wiens, Douglas A.; Stutzmann, Éléonore

    2015-03-01

    The most exciting initiative for the recent polar studies was the International Polar Year (IPY) in 2007-2008. The IPY has witnessed a growing community of seismologists who have made considerable efforts to acquire high-quality data in polar regions. It also provided an excellent opportunity to make significant advances in seismic instrumentation of the polar regions to achieve scientific targets involving global issues. Taking these aspects into account, we organize and publish a special issue in Polar Science on the recent advance in polar seismology and cryoseismology as fruitful achievements of the IPY.

  15. European seismological data exchange, access and processing: current status of the Research Infrastructure project NERIES

    Science.gov (United States)

    Giardini, D.; van Eck, T.; Bossu, R.; Wiemer, S.

    2009-04-01

    The EC Research infrastructure project NERIES, an Integrated Infrastructure Initiative in seismology for 2006-2010 has passed its mid-term point. We will present a short concise overview of the current state of the project, established cooperation with other European and global projects and the planning for the last year of the project. Earthquake data archiving and access within Europe has dramatically improved during the last two years. This concerns earthquake parameters, digital broadband and acceleration waveforms and historical data. The Virtual European Broadband Seismic Network (VEBSN) consists currently of more then 300 stations. A new distributed data archive concept, the European Integrated Waveform Data Archive (EIDA), has been implemented in Europe connecting the larger European seismological waveform data. Global standards for earthquake parameter data (QuakeML) and tomography models have been developed and are being established. Web application technology has been and is being developed to make a jump start to the next generation data services. A NERIES data portal provides a number of services testing the potential capacities of new open-source web technologies. Data application tools like shakemaps, lossmaps, site response estimation and tools for data processing and visualisation are currently available, although some of these tools are still in an alpha version. A European tomography reference model will be discussed at a special workshop in June 2009. Shakemaps, coherent with the NEIC application, are implemented in, among others, Turkey, Italy, Romania, Switzerland, several countries. The comprehensive site response software is being distributed and used both inside and outside the project. NERIES organises several workshops inviting both consortium and non-consortium participants and covering a wide range of subjects: ‘Seismological observatory operation tools', ‘Tomography', ‘Ocean bottom observatories', 'Site response software training

  16. Effects of Seismological and Soil Parameters on Earthquake Energy demand in Level Ground Sand Deposits

    Science.gov (United States)

    nabili, sara; shahbazi majd, nafiseh

    2013-04-01

    Liquefaction has been a source of major damages during severe earthquakes. To evaluate this phenomenon there are several stress, strain and energy based approaches. Use of the energy method has been more focused by researchers due to its advantages with respect to other approaches. The use of the energy concept to define the liquefaction potential is validated through laboratory element and centrifuge tests as well as field studies. This approach is based on the hypothesis that pore pressure buildup is directly related to the dissipated energy in sands which is the accumulated areas between the stress-strain loops. Numerous investigations were performed to find a relationship which correlates the dissipated energy to the soil parameters, but there are not sufficient studies to relate this dissipated energy, known as demand energy, concurrently, to the seismological and the soil parameters. The aim of this paper is to investigate the dependency of the demand energy in sands to seismological and the soil parameters. To perform this task, an effective stress analysis has been executed using FLAC finite difference program. Finn model, which is a built-in constitutive model implemented in FLAC program, was utilized. Since an important stage to predict the liquefaction is the prediction of excess pore water pressure at a given point, a simple numerical framework is presented to assess its generation during a cyclic loading in a given centrifuge test. According to the results, predicted excess pore water pressures did not closely match to the measured excess pore water pressure values in the centrifuge test but they can be used in the numerical assessment of excess pore water pressure with an acceptable degree of preciseness. Subsequently, the centrifuge model was reanalyzed using several real earthquake acceleration records with different seismological parameters such as earthquake magnitude and Hypocentral distance. The accumulated energies (demand energy) dissipated in

  17. Seismological database for Banat seismic region (Romania) - Part 1: The parametric earthquake catalogue

    International Nuclear Information System (INIS)

    Oros, E.; Popa, M.; Moldovan, I. A.

    2008-01-01

    The most comprehensive seismological database for Banat seismic region (Romania) has been achieved. This paper refers to the essential characteristics of the first component of this database, namely the Parametric Earthquakes Catalogue for the Banat Seismic Region (PECBSR). PECBSR comprises 7783 crustal earthquakes (3 ≤ h ≤ 25 km) with 0.4 ≤ M i ≥ 5.6 (M i is M L , M D , M S , M W , Mm and/or mb from compiled sources) occurred in the Banat region and its surroundings between years 1443 and 2006. Different magnitude scales were converted into moment magnitude scale, Mw. The completeness of PECBSR strongly depends on the time. (authors)

  18. Evaluation results after seven years of operation for the permanent Hellenic Seismological Network of Crete (HSNC).

    Science.gov (United States)

    Vallianatos, F.; Hloupis, G.; Papadopoulos, I.

    2012-04-01

    The Hellenic arc and the adjacent areas of the Greek mainland are the most active in western Eurasia and some of the most seismically active zones of the world. The seismicity of South Aegean is extremely high and is characterised by the frequent occurrence of large shallow and intermediate depth earthquakes. Until 2004, the installed seismological stations from several providers (NOA, GEOFON, MEDNET) provide average interstation distance around 130km resulting to catalogues with minimum magnitude of completeness (Mc) equals to 3.7. Towards to the direction of providing dense and state of the art instrumental coverage of seismicity in the South Aegean, HSNC begun its operation in 2004. Today it consists of (12) permanent seismological stations equipped with short period and broadband seismographs coupled with 3rd generation 24bit data loggers as well as from (2) accelerographs . The addition of HSNC along with combined use of all the active networks in South Aegean area (NOA, GEOFON, AUTH) decrease the average interstation distance to 60km and provide catalogues with Mc≥3.2. Data transmission and telemetry is implemented by a hybrid network consisting of dedicated wired ADSL links as well as VSAT links by using a unique private satellite hub. Real time data spread over collaborating networks (AUTH) and laboratories (Department of Earth Science - UCL) while at the same time, events are appended automatically and manually to EMSC database. Additional value to the network is provided by means of prototype systems which deployed in-situ for the purposes of: a) Acquiring aftershock data in the minimum time after main event. This is a mobile seismological network called RaDeSeis (Rapid Deployment Seismological network) which consists of a central station acting also as the central communication hub and wifi coupled mobile stations. b) The development of dedicated hardware and software solutions for rapid installation times (around 1 hour for each station) leading to

  19. 25 Years of Research in Earth Physics and One Century of Seismology in Romania

    International Nuclear Information System (INIS)

    Marmureanu, Gh.

    2002-01-01

    The conference '25 Years of Research in Earth Physics and One Century of Seismology in Romania' held at Bucharest, Romania on September 27-29, 2002 was structured as follows: 1. Keynote lectures (4 papers); Section 1 - Exchange of data and improvement of earthquake monitoring during the last 25 years (6 papers); Section 2 - Study of the seismic source (5 papers); Section 3 - Seismotectonics and geodynamics of the Carphato - Balkan area (16 papers); Section 4 - Seismic hazard assesment (14 papers); Section 5 - Earthquake prediction research (7 papers); Section 6 - Lessons from earthquake damage and policies for seismic risk mitigation (3 papers)

  20. Vitamin and Mineral Supplement Fact Sheets

    Science.gov (United States)

    ... website Submit Search NIH Office of Dietary Supplements Vitamin and Mineral Supplement Fact Sheets Search the list ... Supplements: Background Information Botanical Dietary Supplements: Background Information Vitamin and Mineral Fact Sheets Botanical Supplement Fact Sheets ...

  1. Transcaval TIPS in patients with failed revision of occluded previous TIPS

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Chang Kyu; Kim, Yong Joo; Shin, Tae Beom; Park, Hyo Yong; Kim, Tae Hun; Kang, Duk Sik [Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

    2001-12-01

    To determine the feasibility of transcaval transjugular intrahepatic portosystemic shunt (TIPS) in patients with occluded previous TIPS. Between February 1996 and December 2000 we performed five transcaval TIPS procedures in four patients with recurrent gastric cardiac variceal bleeding. All four had occluded TIPS, which was between the hepatic and portal vein. The interval between initial TIPS placement and revisional procedures with transcaval TIPS varied between three and 31 months; one patient underwent transcaval TIPS twice, with a 31-month interval. After revision of the occluded shunt failed, direct cavoportal puncture at the retrohepatic segment of the IVC was attempted. Transcaval TIPS placement was technically successful in all cases. In three, tractography revealed slight leakage of contrast materials into hepatic subcapsular or subdiaphragmatic pericaval space. There was no evidence of propagation of extravasated contrast materials through the retroperitoneal space or spillage into the peritoneal space. After the tract was dilated by a bare stent, no patient experienced trans-stent bleeding and no serious procedure-related complications occurred. After successful shunt creation, variceal bleeding ceased in all patients. Transcaval TIPS placement is an effective and safe alternative treatment in patients with occluded previous TIPS and no hepatic veins suitable for new TIPS.

  2. The tipping point: A mathematical model for the profit-driven abandonment of restaurant tipping

    Science.gov (United States)

    Clifton, Sara M.; Herbers, Eileen; Chen, Jack; Abrams, Daniel M.

    2018-02-01

    The custom of voluntarily tipping for services rendered has gone in and out of fashion in America since its introduction in the 19th century. Restaurant owners that ban tipping in their establishments often claim that social justice drives their decisions, but we show that rational profit-maximization may also justify the decisions. Here, we propose a conceptual model of restaurant competition for staff and customers, and we show that there exists a critical conventional tip rate at which restaurant owners should eliminate tipping to maximize profits. Because the conventional tip rate has been increasing steadily for the last several decades, our model suggests that restaurant owners may abandon tipping en masse when that critical tip rate is reached.

  3. Selectively reflective transparent sheets

    Science.gov (United States)

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  4. Superfund fact sheet: The remedial program. Fact sheet

    International Nuclear Information System (INIS)

    1992-09-01

    The fact sheet describes what various actions the EPA can take to clean up hazardous wastes sites. Explanations of how the criteria for environmental and public health risk assessment are determined and the role of state and local governments in site remediation are given. The fact sheet is one in a series providing reference information about Superfund issues and is intended for readers with no formal scientific training

  5. Seismological and geological investigation for earthquake hazard in the Greater Accra Metropolitan Area

    International Nuclear Information System (INIS)

    Doku, M. S.

    2013-07-01

    A seismological and geological investigation for earthquake hazard in the Greater Accra Metropolitan Area was undertaken. The research was aimed at employing a methematical model to estimate the seismic stress for the study area by generating a complete, unified and harmonized earthquake catalogue spanning 1615 to 2012. Seismic events were souced from Leydecker, G. and P. Amponsah, (1986), Ambraseys and Adams, (1986), Amponsah (2008), Geological Survey Department, Accra, Ghana, Amponsah (2002), National Earthquake Information Service, United States Geological Survey, Denver, Colorado 80225, USA, the International Seismological Centre and the National Data Centre of the Ghana Atomic Energy Commission. Events occurring in the study area were used to create and Epicentral Intensity Map and a seismicity map of the study area after interpolation of missing seismic magnitudes. The least square method and the maximum likelihood estimation method were employed to evaluate b-values of 0.6 and 0.9 respectively for the study area. A thematic map of epicentral intensity superimposed on the geology of the study area was also developed to help understand the relationship between the virtually fractured, jointed and sheared geology and the seismic events. The results obtained are indicative of the fact that the stress level of GAMA has a telling effect on its seismicity and also the events are prevalents at fractured, jointed and sheared zones. (au)

  6. The CTBTO Link to the database of the International Seismological Centre (ISC)

    Science.gov (United States)

    Bondar, I.; Storchak, D. A.; Dando, B.; Harris, J.; Di Giacomo, D.

    2011-12-01

    The CTBTO Link to the database of the International Seismological Centre (ISC) is a project to provide access to seismological data sets maintained by the ISC using specially designed interactive tools. The Link is open to National Data Centres and to the CTBTO. By means of graphical interfaces and database queries tailored to the needs of the monitoring community, the users are given access to a multitude of products. These include the ISC and ISS bulletins, covering the seismicity of the Earth since 1904; nuclear and chemical explosions; the EHB bulletin; the IASPEI Reference Event list (ground truth database); and the IDC Reviewed Event Bulletin. The searches are divided into three main categories: The Area Based Search (a spatio-temporal search based on the ISC Bulletin), the REB search (a spatio-temporal search based on specific events in the REB) and the IMS Station Based Search (a search for historical patterns in the reports of seismic stations close to a particular IMS seismic station). The outputs are HTML based web-pages with a simplified version of the ISC Bulletin showing the most relevant parameters with access to ISC, GT, EHB and REB Bulletins in IMS1.0 format for single or multiple events. The CTBTO Link offers a tool to view REB events in context within the historical seismicity, look at observations reported by non-IMS networks, and investigate station histories and residual patterns for stations registered in the International Seismographic Station Registry.

  7. The GINGERino ring laser gyroscope, seismological observations at one year from the first light

    Science.gov (United States)

    Simonelli, Andreino; Belfi, Jacopo; Beverini, Nicolò; Di Virgilio, Angela; Carelli, Giorgio; Maccioni, Enrico; De Luca, Gaetano; Saccorotti, Gilberto

    2016-04-01

    The GINGERino ring laser gyroscope (RLG) is a new large observatory-class RLG located in Gran Sasso underground laboratory (LNGS), one national laboratory of the INFN (Istituto Nazionale di Fisica Nucleare). The GINGERino apparatus funded by INFN in the context of a larger project of fundamental physics is intended as a pathfinder instrument to reach the high sensitivity needed to observe general relativity effects; more details are found at the URL (https://web2.infn.it/GINGER/index.php/it/). The sensitivity reached by our instrument in the first year after the set up permitted us to acquire important seismological data of ground rotations during the transit of seismic waves generated by seisms at different epicentral distances. RLGs are in fact the best sensors for capturing the rotational motions associated with the transit of seismic waves, thanks to the optical measurement principle, these instruments are in fact insensitive to translations. Ground translations are recorded by two seismometers: a Nanometrics Trillium 240 s and Guralp CMG 3T 360 s, the first instrument is part of the national earthquake monitoring program of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and provides the ground translation data to be compared to the RLG rotational data. We report the waveforms and the seismological analysis of some seismic events recorded during our first year of activity inside the LNGS laboratory.

  8. ObspyDMT: a Python toolbox for retrieving and processing large seismological data sets

    Directory of Open Access Journals (Sweden)

    K. Hosseini

    2017-10-01

    Full Text Available We present obspyDMT, a free, open-source software toolbox for the query, retrieval, processing and management of seismological data sets, including very large, heterogeneous and/or dynamically growing ones. ObspyDMT simplifies and speeds up user interaction with data centers, in more versatile ways than existing tools. The user is shielded from the complexities of interacting with different data centers and data exchange protocols and is provided with powerful diagnostic and plotting tools to check the retrieved data and metadata. While primarily a productivity tool for research seismologists and observatories, easy-to-use syntax and plotting functionality also make obspyDMT an effective teaching aid. Written in the Python programming language, it can be used as a stand-alone command-line tool (requiring no knowledge of Python or can be integrated as a module with other Python codes. It facilitates data archiving, preprocessing, instrument correction and quality control – routine but nontrivial tasks that can consume much user time. We describe obspyDMT's functionality, design and technical implementation, accompanied by an overview of its use cases. As an example of a typical problem encountered in seismogram preprocessing, we show how to check for inconsistencies in response files of two example stations. We also demonstrate the fully automated request, remote computation and retrieval of synthetic seismograms from the Synthetics Engine (Syngine web service of the Data Management Center (DMC at the Incorporated Research Institutions for Seismology (IRIS.

  9. Urban Seismology: on the origin of earth vibrations within a city.

    Science.gov (United States)

    Díaz, Jordi; Ruiz, Mario; Sánchez-Pastor, Pilar S; Romero, Paula

    2017-11-10

    Urban seismology has become an active research field in the recent years, both with seismological objectives, as obtaining better microzonation maps in highly populated areas, and with engineering objectives, as the monitoring of traffic or the surveying of historical buildings. We analyze here the seismic records obtained by a broad-band seismic station installed in the ICTJA-CSIC institute, located near the center of Barcelona city. Although this station was installed to introduce visitors to earth science during science fairs and other dissemination events, the analysis of the data has allowed to infer results of interest for the scientific community. The main results include the evidence that urban seismometers can be used as a easy-to-use, robust monitoring tool for road traffic and subway activity inside the city. Seismic signals generated by different cultural activities, including rock concerts, fireworks or football games, can be detected and discriminated from its seismic properties. Beside the interest to understand the propagation of seismic waves generated by those rather particular sources, those earth shaking records provide a powerful tool to gain visibility in the mass media and hence have the opportunity to present earth sciences to a wider audience.

  10. Coronal Seismology of Flare-Excited Standing Slow-Mode Waves Observed by SDO/AIA

    Science.gov (United States)

    Wang, Tongjiang; Ofman, Leon; Davila, Joseph M.

    2016-05-01

    Flare-excited longitudinal intensity oscillations in hot flaring loops have been recently detected by SDO/AIA in 94 and 131 Å bandpasses. Based on the interpretation in terms of a slow-mode wave, quantitative evidence of thermal conduction suppression in hot (>9 MK) loops has been obtained for the first time from measurements of the polytropic index and phase shift between the temperature and density perturbations (Wang et al. 2015, ApJL, 811, L13). This result has significant implications in two aspects. One is that the thermal conduction suppression suggests the need of greatly enhanced compressive viscosity to interpret the observed strong wave damping. The other is that the conduction suppression provides a reasonable mechanism for explaining the long-duration events where the thermal plasma is sustained well beyond the duration of impulsive hard X-ray bursts in many flares, for a time much longer than expected by the classical Spitzer conductive cooling. In this study, we model the observed standing slow-mode wave in Wang et al. (2015) using a 1D nonlinear MHD code. With the seismology-derived transport coefficients for thermal conduction and compressive viscosity, we successfully simulate the oscillation period and damping time of the observed waves. Based on the parametric study of the effect of thermal conduction suppression and viscosity enhancement on the observables, we discuss the inversion scheme for determining the energy transport coefficients by coronal seismology.

  11. Citizen seismology in Taiwan: what went wrong and what is the future?

    Science.gov (United States)

    Chen, K. H.; Liang, W. T.; Wu, Y. F.

    2017-12-01

    Citizen seismology encourages the public involvement to data collection, analysis, and reporting, and has the potential to greatly improve the emergency response to seismic hazard. This of course, is important for scientific achievement due to the dense network. We believed the value of citizen seismology and started with distributing Quake-Catcher-Network (QCN) sensor at schools in Taiwan. While working with teachers, we hoped to motivate the learning of how to read seismograms, what to see in the data, and what to teach in the class. Through lots of workshops and activities, even with near-real time earthquake game competition and board game (quake-nopoly) developed along the way, we came to realize the huge gap between what people need and what we do. And to bridge the gap, a new generation of citizen seismic network is needed. Imagine at work, you receive the alarm from sensors at home that tells you the location, size, and type of anomalous shaking events in the neighborhood. Can this future "warning" system happen, allowing citizen to do emergence response? This is a story about facing the challenge, transforming the doubt of "why do I care" to a future IoT world.

  12. ObspyDMT: a Python toolbox for retrieving and processing large seismological data sets

    Science.gov (United States)

    Hosseini, Kasra; Sigloch, Karin

    2017-10-01

    We present obspyDMT, a free, open-source software toolbox for the query, retrieval, processing and management of seismological data sets, including very large, heterogeneous and/or dynamically growing ones. ObspyDMT simplifies and speeds up user interaction with data centers, in more versatile ways than existing tools. The user is shielded from the complexities of interacting with different data centers and data exchange protocols and is provided with powerful diagnostic and plotting tools to check the retrieved data and metadata. While primarily a productivity tool for research seismologists and observatories, easy-to-use syntax and plotting functionality also make obspyDMT an effective teaching aid. Written in the Python programming language, it can be used as a stand-alone command-line tool (requiring no knowledge of Python) or can be integrated as a module with other Python codes. It facilitates data archiving, preprocessing, instrument correction and quality control - routine but nontrivial tasks that can consume much user time. We describe obspyDMT's functionality, design and technical implementation, accompanied by an overview of its use cases. As an example of a typical problem encountered in seismogram preprocessing, we show how to check for inconsistencies in response files of two example stations. We also demonstrate the fully automated request, remote computation and retrieval of synthetic seismograms from the Synthetics Engine (Syngine) web service of the Data Management Center (DMC) at the Incorporated Research Institutions for Seismology (IRIS).

  13. Tipping device for large components

    International Nuclear Information System (INIS)

    Guigon, J.P.; Beraudier, D.

    1984-01-01

    For large components machining as components of a pressurized water reactor, it is necessary to have means allowing to present them in a position determined with regard to the machine tool used. The aim of the invention is a tipping device which consists of a base resting on the ground, a support-table mounted on this base, moving in rotation with the aid of at least a pivot joint of which axis is horizontal and parallel to the table and a gear pivot allowing to get a very good precision for the orientation of the piece and a very good stability whatever the orientation may be. The output shaft pinion of the base meshes with a gear wheel segment fixed to the table structure. Safety straps fasten the table structure to the base, as they are secured by horizontal pins. The toe pins run in straight slot holes incorporated in base jaws. The table rotation may be controlled by a spring-loaded braking mechanism which acts on the pivot axis and can be released by a hydraulic jack. The hydraulic pressure is used to prevent motor operation, unless the brakes have been released [fr

  14. Tipping Points, Great and Small

    Science.gov (United States)

    Morrison, Foster

    2010-12-01

    The Forum by Jordan et al. [2010] addressed environmental problems of various scales in great detail, but getting the critical message through to the formulators of public policies requires going back to basics, namely, that exponential growth (of a population, an economy, or most anything else) is not sustainable. When have you heard any politician or economist from anywhere across the ideological spectrum say anything other than that more growth is essential? There is no need for computer models to demonstrate “limits to growth,” as was done in the 1960s. Of course, as one seeks more details, the complexity of modeling will rapidly outstrip the capabilities of both observation and computing. This is common with nonlinear systems, even simple ones. Thus, identifying all possible “tipping points,” as suggested by Jordan et al. [2010], and then stopping just short of them, is impractical if not impossible. The main thing needed to avoid environmental disasters is a bit of common sense.

  15. Super-large optical gyroscopes for applications in geodesy and seismology: state-of-the-art and development prospects

    International Nuclear Information System (INIS)

    Velikoseltsev, A A; Luk'yanov, D P; Vinogradov, V I; Shreiber, K U

    2014-01-01

    A brief survey of the history of the invention and development of super-large laser gyroscopes (SLLGs) is presented. The basic results achieved using SLLGs in geodesy, seismology, fundamental physics and other fields are summarised. The concept of SLLG design, specific features of construction and implementation are considered, as well as the prospects of applying the present-day optical technologies to laser gyroscope engineering. The possibilities of using fibre-optical gyroscopes in seismologic studies are analysed and the results of preliminary experimental studies are presented. (laser gyroscopes)

  16. Super-large optical gyroscopes for applications in geodesy and seismology: state-of-the-art and development prospects

    Energy Technology Data Exchange (ETDEWEB)

    Velikoseltsev, A A; Luk' yanov, D P [St. Petersburg Electrotechnical University ' ' LETI' ' , St. Petersburg (Russian Federation); Vinogradov, V I [OJSC Tambov factory Elektropribor (Russian Federation); Shreiber, K U [Forschungseinrichtung Satellitengeodaesie, Technosche Universitaet Muenchen, Geodaetisches Observatorium Wettzell, Sackenrieder str. 25, 93444 Bad Koetzting (Germany)

    2014-12-31

    A brief survey of the history of the invention and development of super-large laser gyroscopes (SLLGs) is presented. The basic results achieved using SLLGs in geodesy, seismology, fundamental physics and other fields are summarised. The concept of SLLG design, specific features of construction and implementation are considered, as well as the prospects of applying the present-day optical technologies to laser gyroscope engineering. The possibilities of using fibre-optical gyroscopes in seismologic studies are analysed and the results of preliminary experimental studies are presented. (laser gyroscopes)

  17. Real-time GPS seismology using a single receiver: method comparison, error analysis and precision validation

    Science.gov (United States)

    Li, Xingxing

    2014-05-01

    Earthquake monitoring and early warning system for hazard assessment and mitigation has traditional been based on seismic instruments. However, for large seismic events, it is difficult for traditional seismic instruments to produce accurate and reliable displacements because of the saturation of broadband seismometers and problematic integration of strong-motion data. Compared with the traditional seismic instruments, GPS can measure arbitrarily large dynamic displacements without saturation, making them particularly valuable in case of large earthquakes and tsunamis. GPS relative positioning approach is usually adopted to estimate seismic displacements since centimeter-level accuracy can be achieved in real-time by processing double-differenced carrier-phase observables. However, relative positioning method requires a local reference station, which might itself be displaced during a large seismic event, resulting in misleading GPS analysis results. Meanwhile, the relative/network approach is time-consuming, particularly difficult for the simultaneous and real-time analysis of GPS data from hundreds or thousands of ground stations. In recent years, several single-receiver approaches for real-time GPS seismology, which can overcome the reference station problem of the relative positioning approach, have been successfully developed and applied to GPS seismology. One available method is real-time precise point positioning (PPP) relied on precise satellite orbit and clock products. However, real-time PPP needs a long (re)convergence period, of about thirty minutes, to resolve integer phase ambiguities and achieve centimeter-level accuracy. In comparison with PPP, Colosimo et al. (2011) proposed a variometric approach to determine the change of position between two adjacent epochs, and then displacements are obtained by a single integration of the delta positions. This approach does not suffer from convergence process, but the single integration from delta positions to

  18. TEM observations of crack tip: cavity interactions

    International Nuclear Information System (INIS)

    Horton, J.A.; Ohr, S.M.; Jesser, W.A.

    1981-01-01

    Crack tip-cavity interactions have been studied by performing room temperature deformation experiments in a transmission electron microscope on ion-irradiated type 316 stainless steel with small helium containing cavities. Slip dislocations emitted from a crack tip cut, sheared, and thereby elongated cavities without a volume enlargement. As the crack tip approached, a cavity volume enlargement occurred. Instead of the cavities continuing to enlarge until they touch, the walls between the cavities fractured. Fracture surface dimples do not correlate in size or density with these enlarged cavities

  19. 2012 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  20. State Fact Sheets on COPD

    Science.gov (United States)

    ... Submit Search The CDC Chronic Obstructive Pulmonary Disease (COPD) Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . COPD Homepage Data and Statistics Fact Sheets Publications Publications ...

  1. Australian Government Balance Sheet Management

    OpenAIRE

    Wilson Au-Yeung; Jason McDonald; Amanda Sayegh

    2006-01-01

    Since almost eliminating net debt, the Australian Government%u2019s attention has turned to the financing of broader balance sheet liabilities, such as public sector superannuation. Australia will be developing a significant financial asset portfolio in the %u2018Future Fund%u2019 to smooth the financing of expenses through time. This raises the significant policy question of how best to manage the government balance sheet to reduce risk. This paper provides a framework for optimal balance sh...

  2. Energy information sheets, July 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  3. Energy information sheets, September 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  4. Taking Care of Your Diabetes Means Taking Care of Your Heart (Tip Sheet)

    Science.gov (United States)

    ... foods low in saturated and transfats such as lean meat, chicken without the skin, fish, and non- ... Communication Programs FAQs About NIDDK Meet the Director Offices & Divisions Staff Directory Budget & Legislative Information Advisory & Coordinating ...

  5. The future of ice sheets and sea ice: between reversible retreat and unstoppable loss.

    Science.gov (United States)

    Notz, Dirk

    2009-12-08

    We discuss the existence of cryospheric "tipping points" in the Earth's climate system. Such critical thresholds have been suggested to exist for the disappearance of Arctic sea ice and the retreat of ice sheets: Once these ice masses have shrunk below an anticipated critical extent, the ice-albedo feedback might lead to the irreversible and unstoppable loss of the remaining ice. We here give an overview of our current understanding of such threshold behavior. By using conceptual arguments, we review the recent findings that such a tipping point probably does not exist for the loss of Arctic summer sea ice. Hence, in a cooler climate, sea ice could recover rapidly from the loss it has experienced in recent years. In addition, we discuss why this recent rapid retreat of Arctic summer sea ice might largely be a consequence of a slow shift in ice-thickness distribution, which will lead to strongly increased year-to-year variability of the Arctic summer sea-ice extent. This variability will render seasonal forecasts of the Arctic summer sea-ice extent increasingly difficult. We also discuss why, in contrast to Arctic summer sea ice, a tipping point is more likely to exist for the loss of the Greenland ice sheet and the West Antarctic ice sheet.

  6. Sleep Tips: 7 Steps to Better Sleep

    Science.gov (United States)

    ... turn every night. Consider simple tips for better sleep, from setting a sleep schedule to including physical activity in your daily ... factors that can interfere with a good night's sleep — from work stress and family responsibilities to unexpected ...

  7. Diabetes Prevention: 5 Tips for Taking Control

    Science.gov (United States)

    ... Consider the latest diabetes prevention tips from the American Diabetes Association. There are many benefits to regular physical activity. ... if diabetes testing is appropriate for you. The American Diabetes Association recommends blood glucose screening if: You're age ...

  8. Tips to Help You Get Active

    Science.gov (United States)

    ... A Step in the Right Direction Tips to Help You Get Active View or Print All Sections ... and quality of life. Being more active may help you manage your weight. Starting Physical Activity Healthy ...

  9. Brain Injury Safety Tips and Prevention

    Science.gov (United States)

    ... submit" name="commit" type="submit" value="Submit" /> Brain Injury Safety Tips and Prevention Recommend on Facebook ... not grass or dirt. More HEADS UP Video: Brain Injury Safety and Prevention frame support disabled and/ ...

  10. Tips for Teens with Diabetes: About Diabetes

    Science.gov (United States)

    National Diabetes Education Program (NDEP), 2010

    2010-01-01

    Diabetes is a serious disease. It means that one's blood glucose, also called blood sugar, is too high. Having too much glucose in a person's blood is not healthy. This paper offers tips for managing diabetes.

  11. Daily Tips for Good Oral Hygiene

    Science.gov (United States)

    ... this article Daily Tips for Good Oral Hygiene Bacteria can live in your mouth in the form of plaque, causing cavities and gingivitis, which can lead to periodontal (gum) disease. In order to keep your mouth ...

  12. Impetigo: Tips for Treatment and Prevention

    Science.gov (United States)

    ... DO Videos Contact Close ‹ Back to Healthy Living Impetigo: Tips for Treatment and Prevention The symptoms of ... to other parts of their bodies. Causes of Impetigo Impetigo usually affects preschool and school-aged children, ...

  13. Can't sleep? Try these tips

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000853.htm Can't sleep? Try these tips To use the ... you get the rest you need. What you can do Some people have trouble falling asleep. Others ...

  14. Four Medication Safety Tips for Older Adults

    Science.gov (United States)

    ... Products For Consumers Home For Consumers Consumer Updates 4 Medication Safety Tips for Older Adults Share Tweet ... you are experiencing could be due to medications. 4. Review Medications with Your Health Care Provider Ideally, ...

  15. Essential Outdoor Sun Safety Tips for Winter

    Science.gov (United States)

    ... Weekend Warriors expand/collapse Vitamin D Essential Outdoor Sun Safety Tips for Winter Winter sports enthusiasts are ... skiing! Be Mindful of Time Spent in the Sun, Regardless of the Season If possible, ski early ...

  16. 6 Tips: IBS and Complementary Health Practices

    Science.gov (United States)

    ... health practice for IBS, here are 6 tips: Hypnotherapy (hypnosis). This practice involves the power of suggestion by ... IBS. According to reviews of the scientific literature, hypnotherapy may be a helpful treatment for managing IBS ...

  17. Compressor airfoil tip clearance optimization system

    Science.gov (United States)

    Little, David A.; Pu, Zhengxiang

    2015-08-18

    A compressor airfoil tip clearance optimization system for reducing a gap between a tip of a compressor airfoil and a radially adjacent component of a turbine engine is disclosed. The turbine engine may include ID and OD flowpath boundaries configured to minimize compressor airfoil tip clearances during turbine engine operation in cooperation with one or more clearance reduction systems that are configured to move the rotor assembly axially to reduce tip clearance. The configurations of the ID and OD flowpath boundaries enhance the effectiveness of the axial movement of the rotor assembly, which includes movement of the ID flowpath boundary. During operation of the turbine engine, the rotor assembly may be moved axially to increase the efficiency of the turbine engine.

  18. Tips for Older Dietary Supplement Users

    Science.gov (United States)

    ... Information for Consumers Tips for Older Dietary Supplement Users Share Tweet Linkedin Pin it More sharing options ... site are provided as a service to our users and do not represent FDA endorsement of these ...

  19. Stress induced martensite at the crack tip in NiTi alloys during fatigue loading

    Directory of Open Access Journals (Sweden)

    E. Sgambitterra

    2014-10-01

    Full Text Available Crack tip stress-induced phase transformation mechanisms in nickel-titanium alloys (NiTi were analyzed by Digital Image Correlation (DIC, under fatigue loads. In particular, Single Edge Crack (SEC specimens, obtained from a commercial pseudoelastic NiTi sheet, and an ad-hoc experimental setup were used, for direct measurements of the near crack tip displacement field by the DIC technique. Furthermore, a fitting procedure was developed to calculate the mode I Stress Intensity Factor (SIF, starting from the measured displacement field. Finally, cyclic tensile tests were performed at different operating temperature, in the range 298-338 K, and the evolution of the SIF was studied, which revealed a marked temperature dependence.

  20. FDTD modeling of thin impedance sheets

    Science.gov (United States)

    Luebbers, Raymond J.; Kunz, Karl S.

    1991-01-01

    Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. In this paper it is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods.

  1. The transjugular intrahepatic portosystemic shunt (TIPS)

    International Nuclear Information System (INIS)

    Owen, A.R.; Stanley, A.J.; Vijayananthan, A.; Moss, J.G.

    2009-01-01

    The creation of an intrahepatic portosystemic shunt via a transjugular approach (TIPS) is an interventional radiological procedure used to treat the complications of portal hypertension. TIPS insertion is principally indicated to prevent or arrest variceal bleeding when medical or endoscopic treatments fail, and in the management refractory ascites. This review discusses the development and execution of the technique, with focus on its clinical efficacy. Patient selection, imaging surveillance, revision techniques, and complications are also discussed.

  2. The transjugular intrahepatic portosystemic shunt (TIPS)

    Energy Technology Data Exchange (ETDEWEB)

    Owen, A.R. [Department of Radiology, Austin Health, Heidelberg, Melbourne (Australia)], E-mail: andrewowen@doctors.org.uk; Stanley, A.J. [Department of Gastroenterology, Glasgow Royal Infirmary, Glasgow (United Kingdom); Vijayananthan, A. [Department of Biomedical Imaging, University of Malaya, Kuala Lumpur (Malaysia); Moss, J.G. [Department of Radiology, Gartnavel General Hospital, Glasgow (United Kingdom)

    2009-07-15

    The creation of an intrahepatic portosystemic shunt via a transjugular approach (TIPS) is an interventional radiological procedure used to treat the complications of portal hypertension. TIPS insertion is principally indicated to prevent or arrest variceal bleeding when medical or endoscopic treatments fail, and in the management refractory ascites. This review discusses the development and execution of the technique, with focus on its clinical efficacy. Patient selection, imaging surveillance, revision techniques, and complications are also discussed.

  3. Crustal Models Assessment in Western Part of Romania Employing Active Seismic and Seismologic Methods

    Science.gov (United States)

    Bala, Andrei; Toma-Danila, Dragos; Tataru, Dragos; Grecu, Bogdan

    2017-12-01

    In the years 1999 - 2000 two regional seismic refraction lines were performed within a close cooperation with German partners from University of Karlsruhe. One of these lines is Vrancea 2001, with 420 km in length, almost half of them recorded in Transylvanian Basin. The structure of the crust along the seismic line revealed a very complicated crustal structure beginning with Eastern Carpathians and continuing in the Transylvanian Basin until Medias. As a result of the development of the National Seismic Network in the last ten years, more than 100 permanent broadband stations are now continuously operating in Romania. Complementary to this national dataset, maintained and developed in the National Institute for Earth Physics, new data emerged from the temporary seismologic networks established during the joint projects with European partners in the last decades. The data gathered so far is valuable both for seismology purposes and crustal structure studies, especially for the western part of the country, where this kind of data were sparse until now. Between 2009 and 2011, a new reference model for the Earth’s crust and mantle of the European Plate was defined through the NERIES project from existing data and models. The database gathered from different kind of measurements in Transylvanian Basin and eastern Pannonian Basin were included in this NERIES model and an improved and upgraded model of the Earth crust emerged for western part of Romania. Although the dataset has its origins in several periods over the last 50 years, the results are homogeneous and they improve and strengthen our image about the depth of the principal boundaries in the crust. In the last chapter two maps regarding these boundaries are constructed, one for mid-crustal boundary and one for Moho. They were build considering all the punctual information available from different sources in active seismic and seismology which are introduced in the general maps from the NERIES project for

  4. Adapting Controlled-source Coherence Analysis to Dense Array Data in Earthquake Seismology

    Science.gov (United States)

    Schwarz, B.; Sigloch, K.; Nissen-Meyer, T.

    2017-12-01

    Exploration seismology deals with highly coherent wave fields generated by repeatable controlled sources and recorded by dense receiver arrays, whose geometry is tailored to back-scattered energy normally neglected in earthquake seismology. Owing to these favorable conditions, stacking and coherence analysis are routinely employed to suppress incoherent noise and regularize the data, thereby strongly contributing to the success of subsequent processing steps, including migration for the imaging of back-scattering interfaces or waveform tomography for the inversion of velocity structure. Attempts have been made to utilize wave field coherence on the length scales of passive-source seismology, e.g. for the imaging of transition-zone discontinuities or the core-mantle-boundary using reflected precursors. Results are however often deteriorated due to the sparse station coverage and interference of faint back-scattered with transmitted phases. USArray sampled wave fields generated by earthquake sources at an unprecedented density and similar array deployments are ongoing or planned in Alaska, the Alps and Canada. This makes the local coherence of earthquake data an increasingly valuable resource to exploit.Building on the experience in controlled-source surveys, we aim to extend the well-established concept of beam-forming to the richer toolbox that is nowadays used in seismic exploration. We suggest adapted strategies for local data coherence analysis, where summation is performed with operators that extract the local slope and curvature of wave fronts emerging at the receiver array. Besides estimating wave front properties, we demonstrate that the inherent data summation can also be used to generate virtual station responses at intermediate locations where no actual deployment was performed. Owing to the fact that stacking acts as a directional filter, interfering coherent wave fields can be efficiently separated from each other by means of coherent subtraction. We

  5. Laboratory-based Interpretation of Seismological Models: Dealing with Incomplete or Incompatible Experimental Data (Invited)

    Science.gov (United States)

    Jackson, I.; Kennett, B. L.; Faul, U. H.

    2009-12-01

    In parallel with cooperative developments in seismology during the past 25 years, there have been phenomenal advances in mineral/rock physics making laboratory-based interpretation of seismological models increasingly useful. However, the assimilation of diverse experimental data into a physically sound framework for seismological application is not without its challenges as demonstrated by two examples. In the first example, that of equation-of-state and elasticity data, an appropriate, thermodynamically consistent framework involves finite-strain expansion of the Helmholz free energy incorporating the Debye approximation to the lattice vibrational energy, as advocated by Stixrude and Lithgow-Bertelloni. Within this context, pressure, specific heat and entropy, thermal expansion, elastic constants and their adiabatic and isothermal pressure derivatives are all calculable without further approximation in an internally consistent manner. The opportunities and challenges of assimilating a wide range of sometimes marginally incompatible experimental data into a single model of this type will be demonstrated with reference to MgO, unquestionably the most thoroughly studied mantle mineral. A neighbourhood-algorithm inversion has identified a broadly satisfactory model, but uncertainties in key parameters associated particularly with pressure calibration remain sufficiently large as to preclude definitive conclusions concerning lower-mantle chemical composition and departures from adiabaticity. The second example is the much less complete dataset concerning seismic-wave dispersion and attenuation emerging from low-frequency forced-oscillation experiments. Significant progress has been made during the past decade towards an understanding of high-temperature, micro-strain viscoelastic relaxation in upper-mantle materials, especially as regards the roles of oscillation period, temperature, grain size and melt fraction. However, the influence of other potentially important

  6. Seismology of Giant Planets: General Overview and Results from the Kepler K2 Observations of Neptune

    Directory of Open Access Journals (Sweden)

    Gaulme Patrick

    2017-01-01

    Full Text Available For this invited contribution, I was asked to give an overview about the application of helio and aster-oseismic techniques to study the interior of giant planets, and to specifically present the recent observations of Neptune by Kepler K2. Seismology applied to giant planets could drastically change our understanding of their deep interiors, as it has happened with the Earth, the Sun, and many main-sequence and evolved stars. The study of giant planets' composition is important for understanding both the mechanisms enabling their formation and the origins of planetary systems, in particular our own. Unfortunately, its determination is complicated by the fact that their interior is thought not to be homogeneous, so that spectroscopic determinations of atmospheric abundances are probably not representative of the planet as a whole. Instead, the determination of their composition and structure must rely on indirect measurements and interior models. Giant planets are mostly fluid and convective, which makes their seismology much closer to that of solar-like stars than that of terrestrial planets. Hence, helioseismology techniques naturally transfer to giant planets. In addition, two alternative methods can be used: photometry of the solar light reflected by planetary atmospheres, and ring seismology in the specific case of Saturn. The current decade has been promising thanks to the detection of Jupiter's acoustic oscillations with the ground-based imaging-spectrometer SYMPA and indirect detection of Saturn's f-modes in its rings by the NASA Cassini orbiter. This has motivated new projects of ground-based and space-borne instruments that are under development. The K2 observations represented the first opportunity to search for planetary oscillations with visible photometry. Despite the excellent quality of K2 data, the noise level of the power spectrum of the light curve was not low enough to detect Neptune's oscillations. The main results from the

  7. Seismology of Giant Planets: General Overview and Results from the Kepler K2 Observations of Neptune

    Science.gov (United States)

    Gaulme, Patrick

    2017-10-01

    For this invited contribution, I was asked to give an overview about the application of helio and aster-oseismic techniques to study the interior of giant planets, and to specifically present the recent observations of Neptune by Kepler K2. Seismology applied to giant planets could drastically change our understanding of their deep interiors, as it has happened with the Earth, the Sun, and many main-sequence and evolved stars. The study of giant planets' composition is important for understanding both the mechanisms enabling their formation and the origins of planetary systems, in particular our own. Unfortunately, its determination is complicated by the fact that their interior is thought not to be homogeneous, so that spectroscopic determinations of atmospheric abundances are probably not representative of the planet as a whole. Instead, the determination of their composition and structure must rely on indirect measurements and interior models. Giant planets are mostly fluid and convective, which makes their seismology much closer to that of solar-like stars than that of terrestrial planets. Hence, helioseismology techniques naturally transfer to giant planets. In addition, two alternative methods can be used: photometry of the solar light reflected by planetary atmospheres, and ring seismology in the specific case of Saturn. The current decade has been promising thanks to the detection of Jupiter's acoustic oscillations with the ground-based imaging-spectrometer SYMPA and indirect detection of Saturn's f-modes in its rings by the NASA Cassini orbiter. This has motivated new projects of ground-based and space-borne instruments that are under development. The K2 observations represented the first opportunity to search for planetary oscillations with visible photometry. Despite the excellent quality of K2 data, the noise level of the power spectrum of the light curve was not low enough to detect Neptune's oscillations. The main results from the K2 observations are

  8. The Hellenic Seismological Network Of Crete (HSNC): Validation and results of the 2013 aftershock sequences

    Science.gov (United States)

    Chatzopoulos, Georgios; Papadopoulos, Ilias; Vallianatos, Filippos

    2015-04-01

    The number and quality of seismological networks in Europe has increased in the past decades. Nevertheless, the need for localized networks monitoring areas of great seismic and scientific interest is constant. Hellenic Seismological Network of Crete (HSNC) covers this need for the vicinity of the South Aegean Sea and Crete Island. In the present work with the use of Z-map software (www.seismo.ethz.ch) the spatial variability of Magnitude of Completeness (Mc) is calculated from HSNC's manual analysis catalogue of events for the period 2011 until today, proving the good coverage of HSNC in the areas. Furthermore the 2013, South Aegean seismicity where two large shallow earthquakes occurred in the vicinity of Crete Island, is discussed. The first event takes place on 15th June 2013 in the front of the Hellenic Arc, south from central Crete, while the second one on 12th October, 2013 on the western part of Crete. The two main shocks and their aftershock sequences have been relocated with the use of hypoinverse earthquake location software and an appropriate crust model. The HSNC identified more than 500 and 300 aftershocks respectively followed after the main events. The detailed construction of aftershocks catalogue permits the applicability of modern theories based on complexity sciences as described recently in the frame of non extensive statistical physics. In addition site effects in the stations locations are presented using event and noise recordings. This work was implemented through the project IMPACT-ARC in the framework of action "ARCHIMEDES III-Support of Research Teams at TEI of Crete" (MIS380353) of the Operational Program "Education and Lifelong Learning" and is co-financed by the European Union (European Social Fund) and Greek national funds References A. Tzanis and F. Vallianatos, "Distributed power-law seismicity changes and crustal deformation in the EW Hellenic Arc", Natural Hazards and Earth Systems Sciences, 3, 179-195, 2003 F. Vallianatos, G

  9. Promoting seismology education through collaboration between university research scientists and school teachers

    Science.gov (United States)

    Brunt, M. R.; Ellins, K. K.; Boyd, D.; Mote, A. S.; Pulliam, J.; Frohlich, C. A.

    2012-12-01

    Participation in the NSF-sponsored Texas Earth and Space Science (TXESS) Revolution teacher professional development project paved the way for several teachers to receive educational seismometers and join the IRIS Seismograph in Schools program. This, in turn, has led to secondary school teachers working with university seismologists on research projects. Examples are the NSF-EarthScope SIEDCAR (Seismic Investigation of Edge Driven Convection Associated with the Rio Grande Rift) project; field studies to compile felt-reports for Texas earthquakes, some which may have been induced by human activities; and a seismic study of the Texas Gulf Coast to investigate ocean-continent transition processes along a passive margin. Such collaborations are mutually beneficial in nature. They help scientists to accomplish their research objectives, involve teachers and their students in the authentic, inquiry-based science, promote public awareness of such projects, and open the doors to advancement opportunities for those teachers involved. In some cases, bringing together research scientists and teachers results in collaborations that produce publishable research. In order to effectively integrate seismology research into 7-12 grade education, one of us (Brunt) established the Eagle Pass Junior High Seismology Team in connection with IRIS Seismograph in Schools, station EPTX (AS-1 seismograph), to teach students about earthquakes using authentic real-time data. The concept has sparked interest among other secondary teachers, leading to the creation of two similarly organized seismology teams: WPTX (Boyd, Williams Preparatory School, Dallas) and THTX (Mote, Ann Richards School for Young Women Leaders, Austin). Although the educational seismometers are basic instruments, they are effective educational tools. Seismographs in schools offer students opportunities to learn how earthquakes are recorded and how modern seismometers work, to collect and interpret seismic data, and to

  10. Superconducting phase transition in STM tips

    Energy Technology Data Exchange (ETDEWEB)

    Eltschka, Matthias; Jaeck, Berthold; Assig, Maximilian; Etzkorn, Markus; Ast, Christian R. [Max Planck Institute for Solid State Research, Stuttgart (Germany); Kern, Klaus [Max Planck Institute for Solid State Research, Stuttgart (Germany); Ecole Polytechnique Federale de Lausanne (Switzerland)

    2015-07-01

    The superconducting properties of systems with dimensions comparable to the London penetration depth considerably differ from macroscopic systems. We have studied the superconducting phase transition of vanadium STM tips in external magnetic fields. Employing Maki's theory we extract the superconducting parameters such as the gap or the Zeeman splitting from differential conductance spectra. While the Zeeman splitting follows the theoretical description of a system with s=1/2 and g=2, the superconducting gaps as well as the critical fields depend on the specific tip. For a better understanding of the experimental results, we solve a one dimensional Usadel equation modeling the superconducting tip as a cone with the opening angle α in an external magnetic field. We find that only a small region at the apex of the tip is superconducting in high magnetic fields and that the order of the phase transition is directly determined by α. Further, the spectral broadening increases with α indicating an intrinsic broadening mechanism due to the conical shape of the tip. Comparing these calculations to our experimental results reveals the order of the superconducting phase transition of the STM tips.

  11. On Jovian plasma sheet structure

    International Nuclear Information System (INIS)

    Khurana, K.K.; Kivelson, M.G.

    1989-01-01

    The authors evaluate several models of Jovian plasma sheet structure by determining how well they organize several aspects of the observed Voyager 2 magnetic field characteristics as a function of Jovicentric radial distance. It is shown that in the local time sector of the Voyager 2 outbound pass (near 0300 LT) the published hinged-magnetodisc models with wave (i.e., models corrected for finite wave velocity effects) are more successful than the published magnetic anomaly model in predicting locations of current sheet crossings. They also consider the boundary between the plasma sheet and the magnetotail lobe which is expected to vary slowly with radial distance. They use this boundary location as a further test of the models of the magnetotail. They show that the compressional MHD waves have much smaller amplitude in the lobes than in the plasma sheet and use this criterion to refine the identification of the plasma-sheet-lobe boundary. When the locations of crossings into and out of the lobes are examined, it becomes evident that the magnetic-anomaly model yields a flaring plasma sheet with a halfwidth of ∼ 3 R J at a radial distance of 20 R J and ∼ 12 R J at a radial distance of 100 R J . The hinged-magnetodisc models with wave, on the other hand, predict a halfwidth of ∼ 3.5 R J independent of distance beyond 20 R J . New optimized versions of the two models locate both the current sheet crossings and lobe encounters equally successfully. The optimized hinged-magnetodisc model suggests that the wave velocity decreases with increasing radial distance. The optimized magnetic anomaly model yields lower velocity contrast than the model of Vasyliunas and Dessler (1981)

  12. Automobile sheet metal part production with incremental sheet forming

    Directory of Open Access Journals (Sweden)

    İsmail DURGUN

    2016-02-01

    Full Text Available Nowadays, effect of global warming is increasing drastically so it leads to increased interest on energy efficiency and sustainable production methods. As a result of adverse conditions, national and international project platforms, OEMs (Original Equipment Manufacturers, SMEs (Small and Mid-size Manufacturers perform many studies or improve existing methodologies in scope of advanced manufacturing techniques. In this study, advanced manufacturing and sustainable production method "Incremental Sheet Metal Forming (ISF" was used for sheet metal forming process. A vehicle fender was manufactured with or without die by using different toolpath strategies and die sets. At the end of the study, Results have been investigated under the influence of method and parameters used.Keywords: Template incremental sheet metal, Metal forming

  13. The "Tsunami Earthquake" of 13 April 1923 in Northern Kamchatka: Seismological and Hydrodynamic Investigations

    Science.gov (United States)

    Salaree, Amir; Okal, Emile A.

    2018-04-01

    We present a seismological and hydrodynamic investigation of the earthquake of 13 April 1923 at Ust'-Kamchatsk, Northern Kamchatka, which generated a more powerful and damaging tsunami than the larger event of 03 February 1923, thus qualifying as a so-called "tsunami earthquake". On the basis of modern relocations, we suggest that it took place outside the fault area of the mainshock, across the oblique Pacific-North America plate boundary, a model confirmed by a limited dataset of mantle waves, which also confirms the slow nature of the source, characteristic of tsunami earthquakes. However, numerical simulations for a number of legitimate seismic models fail to reproduce the sharply peaked distribution of tsunami wave amplitudes reported in the literature. By contrast, we can reproduce the distribution of reported wave amplitudes using an underwater landslide as a source of the tsunami, itself triggered by the earthquake inside the Kamchatskiy Bight.

  14. The West-African craton margin in eastern Senegal: a seismological study

    International Nuclear Information System (INIS)

    Dorbath, Catherine; Dorbath, Louis; Gaulon, Roland; Le Page, Alain

    1983-01-01

    A vertical short period seismological array was operated for six months in earstern Senegal. Large P wave travel-time anomalies are in fairly good relation with the gravity and geological features. Two-dimensional inversion of the data shows the existence of a major vertical discontinuity extending from the surface to 150-200 km depth. The other heterogeneities are mainly located in the crust and related to specific segments of the regional geology: craton, Mauritanides and Senegalo-Mauritanian basin. The main discontinuity dipping to the east is interpreted as the trace of an old subduction slab. We propose the following geodynamical process to explain the formation of the Mauritanides orogenic belt: continental collision after opening of a back-arc marginal basin in late Precambrian and its closure until Devonian

  15. Research and development activities of the Seismology Section for the period January 1982-December 1983

    International Nuclear Information System (INIS)

    Roy, Falguni

    1984-01-01

    The research and development activities of the Seismology Section of the Bhabha Atomic Research Centre (BARC) at Bombay are reported for the period January 1982-December 1983 in the form of summaries. The Section's activities are mainly directed towards detection of underground nuclear explosions. During the report period 64 signals out of about 12000 seismograms which were examined were identified as the signals due to underground nuclear explosions. The instrumentation work for Kolar rockburst research was almost completed under the collaboration programme of BARC with Bharat Gold Mines Ltd. Analytical methods have been developed for interpreting the frequency-magnitude relation of earthquake. These methods will be useful in the seismic estimation of risk in case only restricted data involving events of low magnitude are available. A list of publications of the staff-members of the Section during the report period is given. (M.G.B.)

  16. A Serviced-based Approach to Connect Seismological Infrastructures: Current Efforts at the IRIS DMC

    Science.gov (United States)

    Ahern, Tim; Trabant, Chad

    2014-05-01

    As part of the COOPEUS initiative to build infrastructure that connects European and US research infrastructures, IRIS has advocated for the development of Federated services based upon internationally recognized standards using web services. By deploying International Federation of Digital Seismograph Networks (FDSN) endorsed web services at multiple data centers in the US and Europe, we have shown that integration within seismological domain can be realized. By deploying identical methods to invoke the web services at multiple centers this approach can significantly ease the methods through which a scientist can access seismic data (time series, metadata, and earthquake catalogs) from distributed federated centers. IRIS has developed an IRIS federator that helps a user identify where seismic data from global seismic networks can be accessed. The web services based federator can build the appropriate URLs and return them to client software running on the scientists own computer. These URLs are then used to directly pull data from the distributed center in a very peer-based fashion. IRIS is also involved in deploying web services across horizontal domains. As part of the US National Science Foundation's (NSF) EarthCube effort, an IRIS led EarthCube Building Block's project is underway. When completed this project will aid in the discovery, access, and usability of data across multiple geoscienece domains. This presentation will summarize current IRIS efforts in building vertical integration infrastructure within seismology working closely with 5 centers in Europe and 2 centers in the US, as well as how we are taking first steps toward horizontal integration of data from 14 different domains in the US, in Europe, and around the world.

  17. ObsPy: A Python Toolbox for Seismology - Recent Developments and Applications

    Science.gov (United States)

    Megies, T.; Krischer, L.; Barsch, R.; Sales de Andrade, E.; Beyreuther, M.

    2014-12-01

    ObsPy (http://www.obspy.org) is a community-driven, open-source project dedicated to building a bridge for seismology into the scientific Python ecosystem. It offersa) read and write support for essentially all commonly used waveform, station, and event metadata file formats with a unified interface,b) a comprehensive signal processing toolbox tuned to the needs of seismologists,c) integrated access to all large data centers, web services and databases, andd) convenient wrappers to legacy codes like libtau and evalresp.Python, currently the most popular language for teaching introductory computer science courses at top-ranked U.S. departments, is a full-blown programming language with the flexibility of an interactive scripting language. Its extensive standard library and large variety of freely available high quality scientific modules cover most needs in developing scientific processing workflows. Together with packages like NumPy, SciPy, Matplotlib, IPython, Pandas, lxml, and PyQt, ObsPy enables the construction of complete workflows in Python. These vary from reading locally stored data or requesting data from one or more different data centers through to signal analysis and data processing and on to visualizations in GUI and web applications, output of modified/derived data and the creation of publication-quality figures.ObsPy enjoys a large world-wide rate of adoption in the community. Applications successfully using it include time-dependent and rotational seismology, big data processing, event relocations, and synthetic studies about attenuation kernels and full-waveform inversions to name a few examples. All functionality is extensively documented and the ObsPy tutorial and gallery give a good impression of the wide range of possible use cases.We will present the basic features of ObsPy, new developments and applications, and a roadmap for the near future and discuss the sustainability of our open-source development model.

  18. Uranium mining sites - Thematic sheets

    International Nuclear Information System (INIS)

    2009-01-01

    A first sheet proposes comments, data and key numbers about uranium extraction in France: general overview of uranium mining sites, status of waste rock and tailings after exploitation, site rehabilitation. The second sheet addresses the sources of exposure to ionizing radiations due to ancient uranium mining sites: discussion on the identification of these sources associated with these sites, properly due to mining activities or to tailings, or due to the transfer of radioactive substances towards water and to the contamination of sediments, description of the practice and assessment of radiological control of mining sites. A third sheet addresses the radiological exposure of public to waste rocks, and the dose assessment according to exposure scenarios: main exposure ways to be considered, studied exposure scenarios (passage on backfilled path and grounds, stay in buildings built on waste rocks, keeping mineralogical samples at home). The fourth sheet addresses research programmes of the IRSN on uranium and radon: epidemiological studies (performed on mine workers; on French and on European cohorts, French and European studies on the risk of lung cancer associated with radon in housing), study of the biological effects of chronic exposures. The last sheet addresses studies and expertises performed by the IRSN on ancient uranium mining sites in France: studies commissioned by public authorities, radioactivity control studies performed by the IRSN about mining sites, participation of the IRSN to actions to promote openness to civil society

  19. TIPS Evaluation Project Retrospective Study: Wave 1 and 2.

    Science.gov (United States)

    Hubbard, Susan M.; Mulvey, Kevin P.

    2003-01-01

    Measured substance abuse treatment professionals' knowledge, attitudes, and practices regarding the Treatment Improvement Protocol (TIP) series and the 28 TIPs. Results for 3,267 respondents in wave 1 and 1,028 in wave 2 indicate that almost half of all professionals were aware of the TIPs. Attitudes toward TIPs were positive, but professionals…

  20. Root-growth-inhibiting sheet

    Science.gov (United States)

    Burton, F.G.; Cataldo, D.A.; Cline, J.F.; Skiens, W.E.; Van Voris, P.

    1993-01-26

    In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a geotextile'' and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

  1. Optimal swimming of a sheet.

    Science.gov (United States)

    Montenegro-Johnson, Thomas D; Lauga, Eric

    2014-06-01

    Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

  2. Root-growth-inhibiting sheet

    Science.gov (United States)

    Burton, Frederick G.; Cataldo, Dominic A.; Cline, John F.; Skiens, W. Eugene; Van Voris, Peter

    1993-01-01

    In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a "geotextile" and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

  3. Reconstruction of the Tip-Surface Interaction Potential by Analysis of the Brownian Motion of an Atomic Force Microscope Tip

    NARCIS (Netherlands)

    Willemsen, O.H.; Kuipers, L.; van der Werf, Kees; de Grooth, B.G.; Greve, Jan

    2000-01-01

    The thermal movement of an atomic force microscope (AFM) tip is used to reconstruct the tip-surface interaction potential. If a tip is brought into the vicinity of a surface, its movement is governed by the sum of the harmonic cantilever potential and the tip-surface interaction potential. By

  4. Ice sheet hydrology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter; Naeslund, Jens-Ove [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden); Rodhe, Lars [Geological Survey of Sweden, Uppsala (Sweden)

    2007-03-15

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  5. Modelling the Antarctic Ice Sheet

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke; Holm, A.

    2015-01-01

    to sea level high stands during past interglacial periods. A number of AIS models have been developed and applied to try to understand the workings of the AIS and to form a robust basis for future projections of the AIS contribution to sea level change. The recent DCESS (Danish Center for Earth System......The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...

  6. Ice sheet hydrology - a review

    International Nuclear Information System (INIS)

    Jansson, Peter; Naeslund, Jens-Ove; Rodhe, Lars

    2007-03-01

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  7. Sheet Beam Klystron Instability Analysis

    International Nuclear Information System (INIS)

    Bane, K.

    2009-01-01

    Using the principle of energy balance we develop a 2D theory for calculating growth rates of instability in a two-cavity model of a sheet beam klystron. An important ingredient is a TE-like mode in the gap that also gives a longitudinal kick to the beam. When compared with a self-consistent particle-in-cell calculation, with sheet beam klystron-type parameters, agreement is quite good up to half the design current, 65 A; at full current, however, other, current-dependent effects come in and the results deviate significantly

  8. The social balance sheet 2004

    OpenAIRE

    Ph. Delhez; P. Heuse

    2005-01-01

    Each year, in the 4th quarter’s Economic Review, the National Bank examines the provisional results of the social balance sheets. As all the social balance sheets are not yet available for 2004, the study is based on a limited population of enterprises, compiled according to the principle of a constant sample. This population is made up of 38,530 enterprises employing around 1,331,000 workers in 2004. The main results of the analysis, in terms of employment, working hours, labour cost and tra...

  9. Hard-tip, soft-spring lithography.

    Science.gov (United States)

    Shim, Wooyoung; Braunschweig, Adam B; Liao, Xing; Chai, Jinan; Lim, Jong Kuk; Zheng, Gengfeng; Mirkin, Chad A

    2011-01-27

    Nanofabrication strategies are becoming increasingly expensive and equipment-intensive, and consequently less accessible to researchers. As an alternative, scanning probe lithography has become a popular means of preparing nanoscale structures, in part owing to its relatively low cost and high resolution, and a registration accuracy that exceeds most existing technologies. However, increasing the throughput of cantilever-based scanning probe systems while maintaining their resolution and registration advantages has from the outset been a significant challenge. Even with impressive recent advances in cantilever array design, such arrays tend to be highly specialized for a given application, expensive, and often difficult to implement. It is therefore difficult to imagine commercially viable production methods based on scanning probe systems that rely on conventional cantilevers. Here we describe a low-cost and scalable cantilever-free tip-based nanopatterning method that uses an array of hard silicon tips mounted onto an elastomeric backing. This method-which we term hard-tip, soft-spring lithography-overcomes the throughput problems of cantilever-based scanning probe systems and the resolution limits imposed by the use of elastomeric stamps and tips: it is capable of delivering materials or energy to a surface to create arbitrary patterns of features with sub-50-nm resolution over centimetre-scale areas. We argue that hard-tip, soft-spring lithography is a versatile nanolithography strategy that should be widely adopted by academic and industrial researchers for rapid prototyping applications.

  10. Numerical analysis of turbine blade tip treatments

    Science.gov (United States)

    Gopalaswamy, Nath S.; Whitaker, Kevin W.

    1992-01-01

    Three-dimensional solutions of the Navier-Stokes equations for a turbine blade with a turning angle of 180 degrees have been computed, including blade tip treatments involving cavities. The geometry approximates a preliminary design for the GGOT (Generic Gas Oxidizer Turbine). The data presented here will be compared with experimental data to be obtained from a linear cascade using original GGOT blades. Results have been computed for a blade with 1 percent clearance, based on chord, and three different cavity sizes. All tests were conducted at a Reynolds number of 4 x 10 exp 7. The grid contains 39,440 points with 10 spanwise planes in the tip clearance region of 5.008E-04 m. Streamline plots and velocity vectors together with velocity divergence plots reveal the general flow behavior in the clearance region. Blade tip temperature calculations suggest placement of a cavity close to the upstream side of the blade tip for reduction of overall blade tip temperature. The solutions do not account for the relative motion between the endwall and the turbine blade. The solutions obtained are generally consistent with previous work done in this area,

  11. Centrifugal compressor tip clearance and impeller flow

    Energy Technology Data Exchange (ETDEWEB)

    Jaatinen-Varri, Ahti; Tiainen, Jonna; Turunen-Saaresti, Teemu; Gronman, Aki; Ameli, Alireza; Backman, Jari [Laboratory of Fluid Dynamics, LUT School of Energy Systems, Lappeenranta University of Technology, Lappeenranta (Finland); Engeda, Abraham [Turbomachinery Laboratory, Dept. of Mechanical Engineering, Michigan State University, East Lansing (United States)

    2016-11-15

    Compressors consume a considerable portion of the electricity used in the industrial sector. Hence, improvements in compressor efficiency lead to energy savings and reduce environmental impacts. The efficiency of an unshrouded centrifugal compressor suffers from leakage flow over the blade tips. The effect of tip leakage flow on the passage flow differs between the full and splitter blade passages. In this study, the differences in the flow fields between the full and splitter blade passages were studied numerically in detail. An industrial high-speed compressor with a design pressure ratio of 1.78 was modelled. Numerical studies were conducted with six different tip clearances and three different diffuser widths. The results show that increasing tip clearance considerably increases the reversed flow into the impeller with an unpinched diffuser. The reversed flow then partly mixes into the flow in the same blade passage it entered the impeller and the rest migrates over the blade, mixing with the tip clearance flow. Furthermore, as the reversed and clearance flow mix into the wake, the wake is weakened. As pinch reduces both the reversed flow and clearance flow, the passage wakes are stronger with pinches. However, the pinch is beneficial as the losses at the impeller outlet decrease.

  12. Centrifugal compressor tip clearance and impeller flow

    International Nuclear Information System (INIS)

    Jaatinen-Varri, Ahti; Tiainen, Jonna; Turunen-Saaresti, Teemu; Gronman, Aki; Ameli, Alireza; Backman, Jari; Engeda, Abraham

    2016-01-01

    Compressors consume a considerable portion of the electricity used in the industrial sector. Hence, improvements in compressor efficiency lead to energy savings and reduce environmental impacts. The efficiency of an unshrouded centrifugal compressor suffers from leakage flow over the blade tips. The effect of tip leakage flow on the passage flow differs between the full and splitter blade passages. In this study, the differences in the flow fields between the full and splitter blade passages were studied numerically in detail. An industrial high-speed compressor with a design pressure ratio of 1.78 was modelled. Numerical studies were conducted with six different tip clearances and three different diffuser widths. The results show that increasing tip clearance considerably increases the reversed flow into the impeller with an unpinched diffuser. The reversed flow then partly mixes into the flow in the same blade passage it entered the impeller and the rest migrates over the blade, mixing with the tip clearance flow. Furthermore, as the reversed and clearance flow mix into the wake, the wake is weakened. As pinch reduces both the reversed flow and clearance flow, the passage wakes are stronger with pinches. However, the pinch is beneficial as the losses at the impeller outlet decrease

  13. SPR Characteristics Curve and Distribution of Residual Stress in Self-Piercing Riveted Joints of Steel Sheets

    Directory of Open Access Journals (Sweden)

    Rezwanul Haque

    2017-01-01

    Full Text Available Neutron diffraction was used to describe the residual stress distributions in self-piercing riveted (SPR joints. The sheet material displayed a compressive residual stress near the joint, and the stress gradually became tensile in the sheet material far away from the joint. The stress in the rivet leg was lower in the thick joint of the softer steel sheet than in the thin joint of the harder steel sheet. This lower magnitude was attributed to the lower force gradient during the rivet flaring stage of the SPR process curve. This study shows how the residual stress results may be related to the physical occurrences that happened during joining, using the characteristics curve. The study also shows that neutron diffraction technique enabled a crack in the rivet tip to be detected which was not apparent from a cross-section.

  14. Nanobits - exchangable and customisable scanning probe tips

    DEFF Research Database (Denmark)

    Yildiz, Izzet

    dimensions: tips suitable for imaging high-aspect ratio structures and sidewall profiles were designed. Tip diameters in the order of 30 nm were reproducibly obtained with the FIB milling and the smallest tip diameter achieved was ... process by providing direct picking up of the NanoBits by the AFM probe was investigated. Two different bending mechanisms were studied for out-of-plane bending studies: FIB irradiation- and the residual stress-driven bending in bimorph structures. With FIB irradiation studies, NanoBits were demonstrated...... of the structure which may be starting at 170°C. The fabricated NanoBits were assembled and their performance as AFM probes were tested at OFFIS. The NanoBits were successfully picked up by a microgripper, collected in a cartridge and mounted to an AFM probe. Performances of the assembled high-aspect-ratio Nano...

  15. Some observations of tip-vortex cavitation

    Science.gov (United States)

    Arndt, R. E. A.; Arakeri, V. H.; Higuchi, H.

    1991-08-01

    Cavitation has been observed in the trailing vortex system of an elliptic platform hydrofoil. A complex dependence on Reynolds number and gas content is noted at inception. Some of the observations can be related to tension effects associated with the lack of sufficiently large-sized nuclei. Inception measurements are compared with estimates of pressure in the vortex obtained from LDV measurements of velocity within the vortex. It is concluded that a complete correlation is not possible without knowledge of the fluctuating levels of pressure in tip-vortex flows. When cavitation is fully developed, the observed tip-vortex trajectory flows. When cavitation is fully developed, the observed tip-vortex trajectory shows a surprising lack of dependence on any of the physical parameters varied, such as angle of attack, Reynolds number, cavitation number, and dissolved gas content.

  16. Tip vortices in the actuator line model

    Science.gov (United States)

    Martinez, Luis; Meneveau, Charles

    2017-11-01

    The actuator line model (ALM) is a widely used tool to represent the wind turbine blades in computational fluid dynamics without the need to resolve the full geometry of the blades. The ALM can be optimized to represent the `correct' aerodynamics of the blades by choosing an appropriate smearing length scale ɛ. This appropriate length scale creates a tip vortex which induces a downwash near the tip of the blade. A theoretical frame-work is used to establish a solution to the induced velocity created by a tip vortex as a function of the smearing length scale ɛ. A correction is presented which allows the use of a non-optimal smearing length scale but still provides the downwash which would be induced using the optimal length scale. Thanks to the National Science Foundation (NSF) who provided financial support for this research via Grants IGERT 0801471, IIA-1243482 (the WINDINSPIRE project) and ECCS-1230788.

  17. Modeling of Unsteady Sheet Cavitation on Marine Propeller Blades

    Directory of Open Access Journals (Sweden)

    Spyros A. Kinnas

    2003-01-01

    Full Text Available Unsteady sheet cavitation is very common on marine propulsor blades. The authors summarize a lifting-surface and a surface-panel model to solve for the unsteady cavitating flow around a propeller that is subject to nonaxisymmetric inflow. The time-dependent extent and thickness of the cavity were determined by using an iterative method. The cavity detachment was determined by applying the smooth detachment criterion in an iterative manner. A nonzeroradius developed vortex cavity model was utilized at the tip of the blade, and the trailing wake geometry was determined using a fully unsteady wake-alignment process. Comparisons of predictions by the two models and measurements from several experiments are given.

  18. Learning from Balance Sheet Visualization

    Science.gov (United States)

    Tanlamai, Uthai; Soongswang, Oranuj

    2011-01-01

    This exploratory study examines alternative visuals and their effect on the level of learning of balance sheet users. Executive and regular classes of graduate students majoring in information technology in business were asked to evaluate the extent of acceptance and enhanced capability of these alternative visuals toward their learning…

  19. Off-Balance Sheet Financing.

    Science.gov (United States)

    Adams, Matthew C.

    1998-01-01

    Examines off-balance sheet financing, the facilities use of outsourcing for selected needs, as a means of saving operational costs and using facility assets efficiently. Examples of using outside sources for energy supply and food services, as well as partnering with business for facility expansion are provided. Concluding comments address tax…

  20. Tip-Based Nanofabrication for Scalable Manufacturing

    Directory of Open Access Journals (Sweden)

    Huan Hu

    2017-03-01

    Full Text Available Tip-based nanofabrication (TBN is a family of emerging nanofabrication techniques that use a nanometer scale tip to fabricate nanostructures. In this review, we first introduce the history of the TBN and the technology development. We then briefly review various TBN techniques that use different physical or chemical mechanisms to fabricate features and discuss some of the state-of-the-art techniques. Subsequently, we focus on those TBN methods that have demonstrated potential to scale up the manufacturing throughput. Finally, we discuss several research directions that are essential for making TBN a scalable nano-manufacturing technology.

  1. Tip-Based Nanofabrication for Scalable Manufacturing

    International Nuclear Information System (INIS)

    Hu, Huan; Somnath, Suhas

    2017-01-01

    Tip-based nanofabrication (TBN) is a family of emerging nanofabrication techniques that use a nanometer scale tip to fabricate nanostructures. Here in this review, we first introduce the history of the TBN and the technology development. We then briefly review various TBN techniques that use different physical or chemical mechanisms to fabricate features and discuss some of the state-of-the-art techniques. Subsequently, we focus on those TBN methods that have demonstrated potential to scale up the manufacturing throughput. Finally, we discuss several research directions that are essential for making TBN a scalable nano-manufacturing technology.

  2. Twelve tips for "flipping" the classroom.

    Science.gov (United States)

    Moffett, Jennifer

    2015-04-01

    The flipped classroom is a pedagogical model in which the typical lecture and homework elements of a course are reversed. The following tips outline the steps involved in making a successful transition to a flipped classroom approach. The tips are based on the available literature alongside the author's experience of using the approach in a medical education setting. Flipping a classroom has a number of potential benefits, for example increased educator-student interaction, but must be planned and implemented carefully to support effective learning.

  3. Windows 7 Annoyances Tips, Secrets, and Solutions

    CERN Document Server

    Karp, David

    2010-01-01

    Windows 7 may be faster and more stable than Vista, but it's a far cry from problem-free. David A. Karp comes to the rescue with the latest in his popular Windows Annoyances series. This thorough guide gives you the tools you need to fix the troublesome parts of this operating system, plus the solutions, hacks, and timesaving tips to make the most of your PC. Streamline Windows Explorer, improve the Search tool, eliminate the Green Ribbon of Death, and tame User Account Control promptsExplore powerful Registry tips and tools, and use them to customize every aspect of Windows and solve its sho

  4. Study of tip loss corrections using CFD rotor computations

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zhu, Wei Jun; Sørensen, Jens Nørkær

    2014-01-01

    Tip loss correction is known to play an important role for engineering prediction of wind turbine performance. There are two different types of tip loss corrections: tip corrections on momentum theory and tip corrections on airfoil data. In this paper, we study the latter using detailed CFD...... computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out...... and compared with CFD results for the NordTank 500 kW turbine and the NREL 5 MW turbine. Comparisons show that BEM with the new tip loss function can predict correctly the loading near the blade tip....

  5. "Earth, from inside and outside - school activities based on seismology and astronomy"

    Science.gov (United States)

    Chivarean, Radu

    2016-04-01

    Through a multidisciplinary work that integrates Geography education with the other Earth Sciences, we developed an educational project to raise the students' awareness of seismic hazard and to disseminate good practices of earthquake safety. The Romanian Educational Seismic Network (ROEDUSEIS) project (started in 2012) is developed and implemented in partnership with schools from different Romanian cities, our school being one of these. In each participating school a SEP educational seismometer is installed. It is the first educational initiative in Romania in the field of seismology involving the National Institute for Earth Physics - NIEP as coordinator. The e-learning platform website (http://www.roeduseis.ro) represents a great opportunity for students to use real advanced research instruments and scientific data analysis tools in their everyday school activities and a link to observations of Earth phenomena and Earth science in general. The most important educational objectives are related to: preparing comprehensive educational materials as resources for training students and teachers in the analysis and interpretation of seismological data, experimentation of new technologies in projecting and implementing new didactic activities, professional development and support for teachers and development of science curriculum module. The scientific objective is to introduce in schools the use of scientific instruments like seismometer and experimental methods (seismic data analysis). The educational materials entitled "Earthquakes and their effects" is organized in a guide for teachers accompanied by a booklet for students. The structure of the educational material is divided in theoretical chapters followed by sections with activities and experiments adapted to the level of understanding particular to our students. The ROEDUSEIS e-platform should be considered as a modern method for teaching and learning that integrates and completes the work in classroom. The

  6. Proceedings of the OECD/NEA workshop on the relations between seismological data and seismic engineering

    International Nuclear Information System (INIS)

    2003-01-01

    The Committee on the Safety of Nuclear Installations (CSNI) of the OECD-NEA co-ordinates the NEA activities concerning the technical aspects of design, construction and operation of nuclear installations insofar as they affect the safety of such installations. The Integrity and Ageing Working Group (IAGE WG) of the CSNI deals with the integrity of structures and components, and has three sub-groups, dealing with the integrity of metal components and structures, ageing of concrete structures, and the seismic behaviour of structures. The sub-group dealing with the seismic behaviour of structures proposed this workshop. The OECD-NEA workshop on the relations between seismological data and seismic engineering analyses was held on October 17-18, 2002. A field visits in the Izmit area where the fault scarp is still visible was organised on Wednesday October 16, 2002. The Ttirkiye Atom Enerjisi Kurumu, TAEK (Turkish Atomic Energy Agency) in Istanbul, Turkey, hosted the workshop. A recommendation of the OECD workshop on the engineering characterisation of seismic input (hosted by the United States Nuclear Regulatory Commission and organised by Brookhaven National Laboratory on November 15-17, 1999) was to foster the growth of interaction between 'design engineers' and 'ground motion specialists'. The objective of the Istanbul workshop is to address this recommendation. The workshop gave seismologists the opportunity to present observed damages and their related ground motions and design engineers the opportunity to present current techniques used in the evaluation of seismic hazards. Bridging the gap between these two fields was a key objective - this workshop was a forum for bringing together the two communities. In addition, the location of the workshop was particularly interesting and provided possibilities for several of the host country participants to discuss the 1999 Kocaeli earthquake. On the basis of lessons learned from large earthquakes over the last decade, the

  7. Tip off the HAT- Epigenetic control of learning and memory by Drosophila Tip60.

    Science.gov (United States)

    Xu, Songjun; Elefant, Felice

    2015-01-01

    Disruption of epigenetic gene control mechanisms involving histone acetylation in the brain causes cognitive impairment, a debilitating hallmark of most neurodegenerative disorders. Histone acetylation regulates cognitive gene expression via chromatin packaging control in neurons. Unfortunately, the histone acetyltransferases (HATs) that generate such neural epigenetic signatures and their mechanisms of action remain unclear. Our recent findings provide insight into this question by demonstrating that Tip60 HAT action is critical for morphology and function of the mushroom body (MB), the learning and memory center in the Drosophila brain. We show that Tip60 is robustly produced in MB Kenyon cells and extending axonal lobes and that targeted MB Tip60 HAT loss results in axonal outgrowth disruption. Functional consequences of loss and gain of Tip60 HAT levels in the MB are evidenced by defects in memory. Tip60 ChIP-Seq analysis reveals enrichment for genes that function in cognitive processes and accordingly, key genes representing these pathways are misregulated in the Tip60 HAT mutant fly brain. Remarkably, increasing levels of Tip60 in the MB rescues learning and memory deficits resulting from Alzheimer's disease associated amyloid precursor protein (APP) induced neurodegeneration. Our studies highlight the potential of HAT activators as a therapeutic option for cognitive disorders.

  8. Dielectrophoretic positioning of single nanoparticles on atomic force microscope tips for tip-enhanced Raman spectroscopy.

    Science.gov (United States)

    Leiterer, Christian; Deckert-Gaudig, Tanja; Singh, Prabha; Wirth, Janina; Deckert, Volker; Fritzsche, Wolfgang

    2015-05-01

    Tip-enhanced Raman spectroscopy, a combination of Raman spectroscopy and scanning probe microscopy, is a powerful technique to detect the vibrational fingerprint of molecules at the nanometer scale. A metal nanoparticle at the apex of an atomic force microscope tip leads to a large enhancement of the electromagnetic field when illuminated with an appropriate wavelength, resulting in an increased Raman signal. A controlled positioning of individual nanoparticles at the tip would improve the reproducibility of the probes and is quite demanding due to usually serial and labor-intensive approaches. In contrast to commonly used submicron manipulation techniques, dielectrophoresis allows a parallel and scalable production, and provides a novel approach toward reproducible and at the same time affordable tip-enhanced Raman spectroscopy tips. We demonstrate the successful positioning of an individual plasmonic nanoparticle on a commercial atomic force microscope tip by dielectrophoresis followed by experimental proof of the Raman signal enhancing capabilities of such tips. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Whooping Cough (Pertussis) - Fact Sheet for Parents

    Science.gov (United States)

    ... months 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Tosferina (pertussis) The best ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

  10. Numerical investigation of three wind turbine blade tips

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, J.; Soerensen, N.N.

    2002-08-01

    The complex three-dimensional flow around three different tip shapes on a rotating wind turbine blade is investigated and analyzed using Computational Fluid Dynamics. Differences in production, flap wise bending moments and forces are discussed. A method for determining the local inflow angle of attack is presented and further analysis is performed on lift and drag coefficients. It is shown that the original Standard tip results in a more concentrated tip vortex leading to a steeper gradient on both tangential and normal forces when approaching the tip, whereas the two tapered tips show a more flat behavior. This again leads to lower flap wise bending moments and lower production for the Standard tip compared to the two tapered tips. At 12 m/s, though, the Swept tip shows a separation pattern on the surface. This separation causes a decrease in normal force and an increase in tangential force. The Taper tip keeps the higher loading causing the flap wise bending moment to be higher as seen in measurements. To determine the radial variation of lift and drag coefficients the local inflow angle of attack is determined. It is shown that the Standard tip experiences a slightly larger angle of attack at the tip compared to the two tapered tips. The lift coefficients are kept at a more constant level for the two tapered tips due to the decrease in chord, while the drag coefficients actually decrease for the two tapered tips, especially for the Swept tip. For the Swept tip at 12 m/s both lift and drag coefficients changed considerably due to the separation. Differences in aerodynamic damping of the three tips were investigated using HAWCDAMP. The Standard tip seems to be slightly less damped with respect to the edgewise vibrations. (au)

  11. Rebuild of the Bulletin of the International Seismological Centre (ISC), part 1: 1964-1979

    Science.gov (United States)

    Storchak, Dmitry A.; Harris, James; Brown, Lonn; Lieser, Kathrin; Shumba, Blessing; Verney, Rebecca; Di Giacomo, Domenico; Korger, Edith I. M.

    2017-12-01

    The data from the Bulletin of the International Seismological Centre (ISC) have always been and still remain in demand for a wide range of studies in Geosciences. The unique features of the Bulletin include long-term coverage (1904-present), the most comprehensive set of included seismic data from the majority of permanent seismic networks at any given time in the history of instrumental recording (currently 150) and homogeneity of the data and their representation. In order to preserve this homogeneity, the ISC has followed its own standard seismic event processing procedures that have not substantially changed until the early 2000s. Several considerable and necessary advancements in the ISC data collection and seismic event location procedures have created a need to rebuild the data for preceding years in line with the new procedures. Thus was set up a project to rebuild the ISC Bulletin for the period from the beginning of the ISC data till the end of data year 2010. The project is known as the Rebuild of the ISC Bulletin. From data month of January 2011, the ISC data have already been processed with the fully tested and established new procedures and do not require an alteration. It was inconceivable even to think about such a project for many tens of years, but great advances in computer power and increased support by the ISC Member-Institutions and Sponsors have given us a chance to perform this project. Having obtained a lot of experience on the way, we believe that within a few years the entire period of the ISC data will be reprocessed and extended for the entire period of instrumental seismological recordings from 1904 till present. The purpose of this article is to describe the work on reprocessing the ISC Bulletin data under the Rebuild project. We also announce the release of the rebuilt ISC Bulletin for the period 1964-1979 with all seismic events reprocessed and relocated in line with the modern ISC procedures, 68,000 new events, 255 new stations

  12. It’s our Fault: Immersing Young Learners in Authentic Practices of Seismology

    Science.gov (United States)

    Kilb, D. L.; Moher, T.; Wiley, J.

    2009-12-01

    The scalable RoomQuake seismology project uses a learning technology framework-embedded phenomena (Moher, 2006)—that simulates seismic phenomena mapped directly onto the physical space of classrooms. This project, aimed at the upper elementary level, situates students as the scientists engaged in an extended investigation designed to discover the spatial, temporal, and intensity distributions of a series of earthquakes. This project emulates earthquake occurrence over a condensed time and spatial span, with students mapping an earthquake fault imagined to be running through their classroom. The students learn: basic seismology terms; ability to identify seismic P- and S-waves; skills associated with trilateration; nomogram/graph reading skills; and the ability to recognize the emergence of a fault based on RoomQuake geometries. From the students’ perspectives, and similar to real-world earthquakes, RoomQuakes occur at unknown times over the course of several weeks. Multiple computers distributed around the perimeter of the classroom serve as simulated seismographs that depict continuous strip-chart seismic recordings. Most of the time the seismograms reflect background noise, but at (apparently) unpredictable times a crescendoing rumble (emanating from a subwoofer) signals a RoomQuake. Hearing this signal, students move to the seismic stations to read the strip charts. Next, the students trilaterate the RoomQuake epicenter by arcing calibrated strings of length proportional to S-P latencies from each seismic station until a common point is identified. Each RoomQuake epicenter is marked by hanging a Styrofoam ball (color-coded by magnitude) from the ceiling. The developing ‘fault’ within the classroom provides an immersive historic record of the RoomQuake’s spatial distribution. Students also maintain a temporal record of events on a large time-line on the wall (recognizing time-related phenomena like aftershocks) and a record of magnitude frequencies on

  13. Complex inner core of the Earth: The last frontier of global seismology

    Science.gov (United States)

    Tkalčić, Hrvoje

    2015-03-01

    The days when the Earth's inner core (IC) was viewed as a homogeneous solid sphere surrounded by the liquid outer core (OC) are now behind us. Due to a limited number of data sampling the IC and a lack of experimentally controlled conditions in the deep Earth studies, it has been difficult to scrutinize competitive hypotheses in this active area of research. However, a number of new concepts linking IC structure and dynamics has been proposed lately to explain different types of seismological observations. A common denominator of recent observational work on the IC is increased complexity seen in IC physical properties such as its isotropic and anisotropic structure, attenuation, inner core boundary (ICB) topography, and its rotational dynamics. For example, small-scale features have been observed to exist as a widespread phenomenon in the uppermost inner core, probably superimposed on much longer-scale features. The characterization of small-scale features sheds light on the nature of the solidification process and helps in understanding seismologically observed hemispherical dichotomy of the IC. The existence of variations in the rate and level of solidification is a plausible physical outcome in an environment where vigorous compositional convection in the OC and variations in heat exchange across the ICB may control the process of crystal growth. However, further progress is hindered by the fact that the current traveltime data of PKIKP waves traversing the IC do not allow discriminating between variations in isotropic P wave velocity and velocity anisotropy. Future studies of attenuation in the IC might provide crucial information about IC structure, although another trade-off exists—that of the relative contribution of scattering versus viscoelastic attenuation and the connection with the material properties. Future installations of dense arrays, cross paths of waves that sample the IC, and corresponding array studies will be a powerful tool to image and

  14. Autonomous BBOBS-NX (NX-2G) for New Era of Ocean Bottom Broadband Seismology

    Science.gov (United States)

    Shiobara, H.; Ito, A.; Sugioka, H.; Shinohara, M.

    2017-12-01

    The broadband ocean bottom seismometer (BBOBS) and its new generation system (BBOBS-NX) have been developed in Japan, and we performed several test and practical observations to create and establish a new category of the ocean floor broadband seismology, since 1999. Now, the data obtained by our BBOBS and BBOBS-NX is proved to be adequate for broadband seismic analyses. Especially, the BBOBS-NX can obtain the horizontal data comparable to land sites in longer periods (10 s -). Moreover, the BBOBST-NX is in practical evaluation for the mobile tilt observation that enables dense geodetic monitoring. The BBOBS-NX system is a powerful tool, although, it has intrinsic limitation of the ROV operation. If this system can be used without the ROV, like as the BBOBS, it should lead us a true breakthrough of ocean bottom seismology. Hereafter, the new autonomous BBOBS-NX is noted as NX-2G in short. The main problem to realize the NX-2G is a tilt of the sensor unit on landing, which exceed the acceptable limit (±8°) in about 50%. As we had no evidence at which moment and how this tilt occurred, we tried to observe it during the BBOBST-NX landing in 2015 by attaching a video camera and an acceleration logger. The result shows that the tilt on landing was determined by the final posture of the system at the penetration into the sediment, and the large oscillating tilt more than ±10° was observed in descending. The function of the NX-2G system is based on 3 stage operations as shown in the image. The glass float is aimed not only to obtain enough buoyancy to extract the sensor unit, but also to suppress the oscillating tilt of the system in descending. In Oct. 2016, we made the first in-situ test of the NX-2G system with a ROV. It was dropped from the sea surface with the video camera and the acceleration logger. The ROV was used to watch the operation of the system at the seafloor. The landing looked well and it was examined from the acceleration data. As the maximum tilt in

  15. Using Social Networks to Educate Seismology to Non-Science Audiences in Costa Rica

    Science.gov (United States)

    Lücke, O. H.; Linkimer, L.

    2013-12-01

    Costa Rica has a very high rate of seismicity with 63 damaging earthquakes in its history as a nation and 12 felt earthquakes per month on average. In Costa Rica, earthquakes are part of everyday life; hence the inhabitants are highly aware of seismic activity and geological processes. However, formal educational programs and mainstream media have not yet addressed the appropriate way of educating the public on these topics, thus myths and misconceptions are common. With the increasing influence of social networks on information diffusion, they have become a new channel to address this issue in Costa Rica. The National Seismological Network of Costa Rica (RSN) is a joint effort between the University of Costa Rica and the Costa Rican Institute of Electricity. Since 1973, the RSN studies the seismicity and volcanic activity in the country. Starting on January 2011 the RSN has an active Facebook Page, in which felt earthquakes are reported and information on Seismology, geological processes, scientific talks, and RSN activities are routinely posted. Additionally, RSN gets almost instantaneous feedback from RSN followers including people from all rural and urban areas of Costa Rica. In this study, we analyze the demographics, geographic distribution, reach of specific Facebook posts per topic, and the episodic growth of RSN followers related to specific seismic events. We observe that 70 % of the RSN users are between ages from 18 to 34. We consistently observe that certain regions of the country have more Facebook activity, although those regions are not the most populated nor have a high connectivity index. We interpret this pattern as the result of a higher awareness to geological hazards in those specific areas. We notice that educational posts are as well 'liked' as most earthquake reports. For exceptional seismic events, we observe sudden increments in the number of RSN followers in the order of tens of thousands. For example, the May 2013 Sixaola earthquake (Mw

  16. Seismology in Schools an integrated approach to funding developing and implementing a coordinated programme for teachers and high school students

    Science.gov (United States)

    Blake, T. A.; Jones, A. G.; Campbell, G.

    2010-12-01

    Statistics in Ireland show that physics at Advanced Level in Secondary Schools is declining in popularity and is the most likely subject to be cut first from the curriculum in a curriculum readjustment by school authorities. In an attempt to attract students to study Earth science and seismology the School of Cosmic Physics, DIAS embarked on an outreach programme in 2007 to promote Earth science, particularly seismology, in schools at both Primary and Secondary Levels. Since its inception, DIAS's Seismology in Schools programme has been very well received, with seismometers installed in over fifty schools across the State. Although this number may appear small, given that the population of Ireland is 4M this number of 1 per 80,000 compares favourably with the U.K. (70 in a population of 70M, 1 per 1M) and the U.S.A. (200 in a population of 300M, 1 per 1.5M) with an penetration of 15-20 times greater. The phenomenal success of our Seismology in Schools programme has been helped significantly by the support we have received from the British Geological Survey (BGS) and IRIS (Incorporated Research Institutions for Seismology) in terms of hardware, software and advice. Similarly, the programme would be a pale reflection of what it is today if the Directors of the Educational Centres (ATECI, Association of Teacher's/Education Centres in Ireland) across Ireland had not become enthused and funded the purchase of 34 additional seismometers, and the Geological Survey of Ireland purchased a further six. Also, funding support from Discover Science and Engineering (DSE) was absolutely critical for us to roll out this hugely enlarged programme of 50 seismometers from the originally envisioned four. As this programme is an initiation into seismology for students, it is important to stress that the seismometer is not used in the schools as a professional recording instrument but helps students visualize what seismology and the recording of earthquakes comprises. Essential to the

  17. The 21 August 2017 Ischia (Italy) Earthquake Source Model Inferred From Seismological, GPS, and DInSAR Measurements

    Science.gov (United States)

    De Novellis, V.; Carlino, S.; Castaldo, R.; Tramelli, A.; De Luca, C.; Pino, N. A.; Pepe, S.; Convertito, V.; Zinno, I.; De Martino, P.; Bonano, M.; Giudicepietro, F.; Casu, F.; Macedonio, G.; Manunta, M.; Cardaci, C.; Manzo, M.; Di Bucci, D.; Solaro, G.; Zeni, G.; Lanari, R.; Bianco, F.; Tizzani, P.

    2018-03-01

    The causative source of the first damaging earthquake instrumentally recorded in the Island of Ischia, occurred on 21 August 2017, has been studied through a multiparametric geophysical approach. In order to investigate the source geometry and kinematics we exploit seismological, Global Positioning System, and Sentinel-1 and COSMO-SkyMed differential interferometric synthetic aperture radar coseismic measurements. Our results indicate that the retrieved solutions from the geodetic data modeling and the seismological data are plausible; in particular, the best fit solution consists of an E-W striking, south dipping normal fault, with its center located at a depth of 800 m. Moreover, the retrieved causative fault is consistent with the rheological stratification of the crust in this zone. This study allows us to improve the knowledge of the volcano-tectonic processes occurring on the Island, which is crucial for a better assessment of the seismic risk in the area.

  18. 21 CFR 880.5180 - Burn sheet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Burn sheet. 880.5180 Section 880.5180 Food and... Burn sheet. (a) Identification. A burn sheet is a device made of a porous material that is wrapped aroung a burn victim to retain body heat, to absorb wound exudate, and to serve as a barrier against...

  19. Manifold free multiple sheet superplastic forming

    Science.gov (United States)

    Elmer, John W.; Bridges, Robert L.

    2004-01-13

    Fluid-forming compositions in a container attached to enclosed adjacent sheets are heated to relatively high temperatures to generate fluids (gases) that effect inflation of the sheets. Fluid rates to the enclosed space between the sheets can be regulated by the canal from the container. Inflated articles can be produced by a continuous, rather than batch-type, process.

  20. On the possible eigenoscillations of neutral sheets

    International Nuclear Information System (INIS)

    Almeida, W.A.; Costa, J.M. da; Aruquipa, E.G.; Sudano, J.P.

    1974-12-01

    A neutral sheet model with hyperbolic tangent equilibrium magnetic field and hyperbolic square secant density profiles is considered. It is shown that the equation for small oscillations takes the form of an eigenvalue oscillation problem. Computed eigenfrequencies of the geomagnetic neutral sheet were found to be in the range of the resonant frequencies of the geomagnetic plasma sheet computed by other authors

  1. Ten Tips for Better Time Management.

    Science.gov (United States)

    Van Loozen, Luann F.

    1982-01-01

    Presents time management tips, especially for board of education members, including recommendations to realize that managing time is a skill, develop a more accurate sense of how one's time is spent, examine and reestablish goals, learn to say no, organize files and information, and master the telephone. (Author/JM)

  2. The Tipping Points of Technology Development

    Directory of Open Access Journals (Sweden)

    Tauno Kekäle

    2014-07-01

    Full Text Available The tipping point, the decisive point in time in the competition between old and new, is an interesting phenomenon in physics of today. This aspect in technology acceptance is connected to many business decisions such as technology investments, product releases, resource allocation, sales forecasts and, ultimately, affects the profitability and even survival of a company. The tipping point itself is based on many stochastic and dynamic variables, and the process may at least partly be described as path-dependent. This paper analyses the tipping point from three aspects: (1 product performance, (2 features of the market and infrastructure (including related technologies and human network externalities, and (3 actions of the incumbents (including customer lock-in, systems lock-in, and sustaining innovation. The paper is based on the Bass s-curve idea and the technology trajectory concept proposed by Dosi. Three illustrative cases are presented to make the point of the multiple factors affecting technology acceptance and, thus, the tipping point. The paper also suggests outlines for further research in field of computer simulation.

  3. Tip Saves Energy, Money for Pennsylvania Plant

    Science.gov (United States)

    A wastewater treatment plant in Berks County, Pennsylvania is saving nearly $45,000 a year and reducing hundreds of metric tons of greenhouse gases since employing an energy conservation tip offered by the Water Protection Division in EPA’s R3 and PADEP.

  4. The Tipping Point and the Adventure Advantage.

    Science.gov (United States)

    Prouty, Dick

    1998-01-01

    Insights from chaos theory--the interconnectedness of everything, nonlinear cause and effect, leverage and the "tipping point," and the importance of aligning interventions within a system--are applied to social action and illustrated via the role of adventure education in school and community interventions in the Brattleboro (Vermont) Leadership…

  5. Adipogenesis: forces that tip the scales

    DEFF Research Database (Denmark)

    MacDougald, Ormond A; Mandrup, Susanne

    2001-01-01

    factors reviewed include Wnt, transforming growth factor beta, inflammatory cytokines and prostaglandin F(2alpha). Tipping the scales towards or away from adipogenesis has profound implications for human health. In this review, we describe recent contributions to the field and will focus on factors...

  6. Can Wing Tip Vortices Be Accurately Simulated?

    Science.gov (United States)

    2011-07-01

    Aerodynamics , Flow Visualization, Numerical Investigation, Aero Suite 16. SECURITY CLASSIFICATION OF: Unclassified 17. LIMITATION OF ABSTRACT 18...additional tail buffeting.2 In commercial applications, winglets have been installed on passenger aircraft to minimize vortex formation and reduce lift...air. In military applications, wing tip In commercial applications, winglets have been installed on passenger aircraft to minimize increases with downstream distances.

  7. Tip cells: master regulators of tubulogenesis?

    Science.gov (United States)

    Weavers, Helen; Skaer, Helen

    2014-07-01

    The normal development of an organ depends on the coordinated regulation of multiple cell activities. Focusing on tubulogenesis, we review the role of specialised cells or groups of cells that are selected from within tissue primordia and differentiate at the outgrowing tips or leading edge of developing tubules. Tip or leading cells develop distinctive patterns of gene expression that enable them to act both as sensors and transmitters of intercellular signalling. This enables them to explore the environment, respond to both tissue intrinsic signals and extrinsic cues from surrounding tissues and to regulate the behaviour of their neighbours, including the setting of cell fate, patterning cell division, inducing polarity and promoting cell movement and cell rearrangements by neighbour exchange. Tip cells are also able to transmit mechanical tension to promote tissue remodelling and, by interacting with the extracellular matrix, they can dictate migratory pathways and organ shape. Where separate tubular structures fuse to form networks, as in the airways of insects or the vascular system of vertebrates, specialised fusion tip cells act to interconnect disparate elements of the developing network. Finally, we consider their importance in the maturation of mature physiological function and in the development of disease. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Social Media Tips to Enhance Medical Education.

    Science.gov (United States)

    Shah, Vikas; Kotsenas, Amy L

    2017-06-01

    In this article, we describe how social media can supplement traditional education, articulate the advantages and disadvantages of various social media platforms for both teachers and learners, discuss best practices to maintain confidentiality of protected health information, and provide tips for implementing social media-based teaching into the training curriculum. Copyright © 2017 The Association of University Radiologists. All rights reserved.

  9. [Effective communication with talkative patients: 10 tips

    NARCIS (Netherlands)

    Giroldi, E.; Veldhuijzen, W.; Bareman, F.; Bueving, H.; Weijden, T.T. van der; Vleuten, C. van der; Muris, J.

    2016-01-01

    Consultations with talkative patients present a challenge to doctors. It is difficult to gather all the necessary information within the available time, without damaging the doctor-patient relationship. Based on the listed existing literature and doctors' experiences, we present ten tips for

  10. Barbecue Basics: Tips to Prevent Foodborne Illness

    Medline Plus

    Full Text Available ... Español Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, ... Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers Consumer Updates Barbecue Basics: Tips to ...

  11. What Do You Mean, 'Tipping Point'?

    NARCIS (Netherlands)

    Nes, van E.H.; Shojaei Arani, M.; Staal, A.; Bolt, van der B.; Flores, Bernardo M.; Bathiany, S.; Scheffer, M.

    2016-01-01

    Over the past 10 years the use of the term ‘tipping point’ in the scientific literature has exploded. It was originally used loosely as a metaphor for the phenomenon that, beyond a certain threshold, runaway change propels a system to a new state. Although several specific mathematical definitions

  12. Final Technical Report: Electrohydrodynamic Tip Streaming

    Energy Technology Data Exchange (ETDEWEB)

    Basaran, Osman [Purdue Univ., West Lafayette, IN (United States)

    2016-01-06

    When subjected to strong electric fields, liquid drops and films form conical tips and emit thin jets from their tips. Such electrodydrodynamic (EDH) tip streaming or cone-jetting phenomena, which are sometimes referred to as electrospraying, occur widely in nature, e.g., in ejection of streams of small charged drops from pointed tips of raindrops in thunderclouds, and technology, e.g., in electrospray mass spectrometry or electric field-driven solvent extraction. More recently, EHD cone-jetting has emerged as a powerful technique for direct printing of solar cells, micro- and nano- particle production, and microencapsulation for controlled release. In many of the aforementioned situations, of equal importance to the processes by which one drop disintegrates to form several drops are those by which (a) two drops come together and coalesce and (b) two drops are coupled to form a double droplet system (DDS) or a capillary switch (CS). the main objective of this research program is to advance through simulation, theory, and experiment the breakup, coalescence, and oscillatory dynamics of single and pairs of charged as well as uncharged drops.

  13. Separation of Stochastic and Deterministic Information from Seismological Time Series with Nonlinear Dynamics and Maximum Entropy Methods

    International Nuclear Information System (INIS)

    Gutierrez, Rafael M.; Useche, Gina M.; Buitrago, Elias

    2007-01-01

    We present a procedure developed to detect stochastic and deterministic information contained in empirical time series, useful to characterize and make models of different aspects of complex phenomena represented by such data. This procedure is applied to a seismological time series to obtain new information to study and understand geological phenomena. We use concepts and methods from nonlinear dynamics and maximum entropy. The mentioned method allows an optimal analysis of the available information

  14. VERCE: a productive e-Infrastructure and e-Science environment for data-intensive seismology research

    Science.gov (United States)

    Vilotte, J. P.; Atkinson, M.; Spinuso, A.; Rietbrock, A.; Michelini, A.; Igel, H.; Frank, A.; Carpené, M.; Schwichtenberg, H.; Casarotti, E.; Filgueira, R.; Garth, T.; Germünd, A.; Klampanos, I.; Krause, A.; Krischer, L.; Leong, S. H.; Magnoni, F.; Matser, J.; Moguilny, G.

    2015-12-01

    Seismology addresses both fundamental problems in understanding the Earth's internal wave sources and structures and augmented societal applications, like earthquake and tsunami hazard assessment and risk mitigation; and puts a premium on open-data accessible by the Federated Digital Seismological Networks. The VERCE project, "Virtual Earthquake and seismology Research Community e-science environment in Europe", has initiated a virtual research environment to support complex orchestrated workflows combining state-of-art wave simulation codes and data analysis tools on distributed computing and data infrastructures (DCIs) along with multiple sources of observational data and new capabilities to combine simulation results with observational data. The VERCE Science Gateway provides a view of all the available resources, supporting collaboration with shared data and methods, with data access controls. The mapping to DCIs handles identity management, authority controls, transformations between representations and controls, and access to resources. The framework for computational science that provides simulation codes, like SPECFEM3D, democratizes their use by getting data from multiple sources, managing Earth models and meshes, distilling them as input data, and capturing results with meta-data. The dispel4py data-intensive framework allows for developing data-analysis applications using Python and the ObsPy library, which can be executed on different DCIs. A set of tools allows coupling with seismology and external data services. Provenance driven tools validate results and show relationships between data to facilitate method improvement. Lessons learned from VERCE training lead us to conclude that solid-Earth scientists could make significant progress by using VERCE e-science environment. VERCE has already contributed to the European Plate Observation System (EPOS), and is part of the EPOS implementation phase. Its cross-disciplinary capabilities are being extended

  15. Construction of Modular Hydrogel Sheets for Micropatterned Macro-scaled 3D Cellular Architecture.

    Science.gov (United States)

    Son, Jaejung; Bae, Chae Yun; Park, Je-Kyun

    2016-01-11

    Hydrogels can be patterned at the micro-scale using microfluidic or micropatterning technologies to provide an in vivo-like three-dimensional (3D) tissue geometry. The resulting 3D hydrogel-based cellular constructs have been introduced as an alternative to animal experiments for advanced biological studies, pharmacological assays and organ transplant applications. Although hydrogel-based particles and fibers can be easily fabricated, it is difficult to manipulate them for tissue reconstruction. In this video, we describe a fabrication method for micropatterned alginate hydrogel sheets, together with their assembly to form a macro-scale 3D cell culture system with a controlled cellular microenvironment. Using a mist form of the calcium gelling agent, thin hydrogel sheets are easily generated with a thickness in the range of 100 - 200 µm, and with precise micropatterns. Cells can then be cultured with the geometric guidance of the hydrogel sheets in freestanding conditions. Furthermore, the hydrogel sheets can be readily manipulated using a micropipette with an end-cut tip, and can be assembled into multi-layered structures by stacking them using a patterned polydimethylsiloxane (PDMS) frame. These modular hydrogel sheets, which can be fabricated using a facile process, have potential applications of in vitro drug assays and biological studies, including functional studies of micro- and macrostructure and tissue reconstruction.

  16. Optimization study on pin tip diameter of an impact-pin nozzle at high pressure ratio

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, C. Palani; Lee, Kwon Hee [FMTRC, Daejoo Machinery Co. Ltd., Daegu (Korea, Republic of); Park, Tae Choon; Cha, Bong Jun [Engine Components Research Team, Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Kim, Heuy Dong [Dept. of Mechanical Engineering, Andong National University, Andong (Korea, Republic of)

    2016-09-15

    Wet compression system is typically installed in a gas turbine engine to increase the net power output and efficiency. A crucial component of the wet compression system is the nozzle which generates fine water droplets for injection into the compressor. The main objective of present work is to optimize a kind of nozzle called impact-pin spray nozzle and thereby produce better quality droplets. To achieve this, the dynamics occurring in the water jet impinging on the pin tip, the subsequent formation of water sheet, which finally breaks into water droplets, must be studied. In this manuscript, the progress on the numerical studies on impact-pin nozzle are reported. A small computational domain covering the orifice, pin tip and the region where primary atomization occurs is selected for numerical analysis. The governing equations are selected in three dimensional cartesian form and simulations are performed to predict the dynamics of water jet impinging on the pin. Systematic studies were carried out and the results leading to the choice of turbulence model and the effect of pin tip diameter are reported here. Further studies are proposed to show the future directions of the present research work.

  17. A Comparative Analysis of Seismological and Gravimetric Crustal Thicknesses below the Andean Region with Flat Subduction of the Nazca Plate

    Directory of Open Access Journals (Sweden)

    Mario E. Gimenez

    2009-01-01

    Full Text Available A gravimetric study was carried out in a region of the Central Andean Range between 28∘ and 32∘ south latitudes and from 72∘ and 66∘ west longitudes. The seismological and gravimetrical Moho models were compared in a sector which coincides with the seismological stations of the CHARGE project. The comparison reveals discrepancies between the gravity Moho depths and those obtained from seismological investigations (CHARGE project, the latter giving deeper values than those resulting from the gravimetric inversion. These discrepancies are attenuated when the positive gravimetric effect of the Nazca plate is considered. Nonetheless, a small residuum of about 5 km remains beneath the Cuyania terrane region, to the east of the main Andean chain. This residuum could be gravimetrically justified if the existence of a high density or eclogitized portion of the lower crust is considered. This result differed from the interpretations from Project “CHARGE” which revealed that the entire inferior crust extending from the Precordillera to the occidental “Sierras Pampeanas” could be “eclogitized”. In this same sector, we calculated the effective elastic thickness (Te of the crust. These results indicated an anomalous value of Te = 30 km below the Cuyania terrane. This is further conclusive evidence of the fact that the Cuyania terrane is allochthonous, for which also geological evidences exist.

  18. Tipping news in information accumulation system

    Science.gov (United States)

    Shin, J. K.

    2010-05-01

    As a continuous opinion dynamics model, the information accumulation system (IAS) includes three basic mechanisms of the news, the inheritance and the diffusion as contributing to the information accumulation process of a system. A system is composed of agents who diffuse information through internal interaction, while each of them has incomplete memory or inheritance rate. The news comes from external sources of information, such as mass media. Previously the model IAS was studied only for the small news problems. In this study, a tipping news problem is considered. A key question of the problem is: what is the minimum strength of advertisement that can tip the minority opinion to a majority one? Dynamics of the IAS is briefly revisited with a special interest on nonlinear behavior of the model. In particular, it is shown that a discrete map of the IAS for a single color problem can be transformed into a logistic map, from which the dynamics of the IAS can be better understood. To show the applicability of the IAS model, the result is applied to explain the concept of the critical population size, which claims that there is a minimum population size for a social knowledge system to be continuously inherited without being lost. And critical size of the tipping news is found analytically in terms of IAS parameters. Some of the key results from the present study are compared in detail with the results from the Brownian particle model, which is believed to be the most similar model to the IAS. The concept of tipping news is used to show that a traditional society can tip at an exceptionally low inter-community exposure. Finally, the result was applied to the language competition problem.

  19. Mode I fracture toughness analysis of a single-layer grapheme sheet

    Energy Technology Data Exchange (ETDEWEB)

    Ky, Minh Nguyen; Yum, Young Jin [University of Ulsan, Ulsan (Korea, Republic of)

    2014-09-15

    To predict the fracture toughness of a single-layer graphene sheet (SLGS), analytical formulations were devised for the hexagonal honeycomb lattice using a linkage equivalent discrete frame structure. Broken bonds were identified by a sharp increase in the position of the atoms. As crack propagation progressed, the crack tip position and crack path were updated from broken bonds in the molecular dynamics (MD) model. At each step in the simulation, the atomic model was centered on the crack tip to adaptively follow its path. A new formula was derived analytically from the deformation and bending mechanism of solid-state carbon-carbon bonds so as to describe the mode I fracture of SLGS. The fracture toughness of single-layer graphene is governed by a competition between bond breaking and bond rotation at a crack tip. K-field based displacements were applied on the boundary of the micromechanical model, and FEM results were obtained and compared with theoretical findings. The critical stress intensity factor for a graphene sheet was found to be K{sub IC} = 2.63 ∼ 3.2 MPa√m for the case of a zigzag crack.

  20. SEISMOLOGY OF A LARGE SOLAR CORONAL LOOP FROM EUVI/STEREO OBSERVATIONS OF ITS TRANSVERSE OSCILLATION

    International Nuclear Information System (INIS)

    Verwichte, E.; Van Doorsselaere, T.; Foullon, C.; Nakariakov, V. M.; Aschwanden, M. J.

    2009-01-01

    The first analysis of a transverse loop oscillation observed by both Solar TErrestrial RElations Observatories (STEREO) spacecraft is presented, for an event on the 2007 June 27 as seen by the Extreme Ultraviolet Imager (EUVI). The three-dimensional loop geometry is determined using a three-dimensional reconstruction with a semicircular loop model, which allows for an accurate measurement of the loop length. The plane of wave polarization is found from comparison with a simulated loop model and shows that the oscillation is a fundamental horizontally polarized fast magnetoacoustic kink mode. The oscillation is characterized using an automated method and the results from both spacecraft are found to match closely. The oscillation period is 630 ± 30 s and the damping time is 1000 ± 300 s. Also, clear intensity variations associated with the transverse loop oscillations are reported for the first time. They are shown to be caused by the effect of line-of-sight integration. The Alfven speed and coronal magnetic field derived using coronal seismology are discussed. This study shows that EUVI/STEREO observations achieve an adequate accuracy for studying long-period, large-amplitude transverse loop oscillations.

  1. USING HINODE/EXTREME-ULTRAVIOLET IMAGING SPECTROMETER TO CONFIRM A SEISMOLOGICALLY INFERRED CORONAL TEMPERATURE

    International Nuclear Information System (INIS)

    Marsh, M. S.; Walsh, R. W.

    2009-01-01

    The Extreme-Ultraviolet Imaging Spectrometer on board the HINODE satellite is used to examine the loop system described in Marsh et al. by applying spectroscopic diagnostic methods. A simple isothermal mapping algorithm is applied to determine where the assumption of isothermal plasma may be valid, and the emission measure locii technique is used to determine the temperature profile along the base of the loop system. It is found that, along the base, the loop has a uniform temperature profile with a mean temperature of 0.89 ± 0.09 MK which is in agreement with the temperature determined seismologically in Marsh et al., using observations interpreted as the slow magnetoacoustic mode. The results further strengthen the slow mode interpretation, propagation at a uniform sound speed, and the analysis method applied in Marsh et al. It is found that it is not possible to discriminate between the slow mode phase speed and the sound speed within the precision of the present observations.

  2. Tidal and seasonal variations in calving flux observed with passive seismology

    Science.gov (United States)

    Bartholomaus, T.C.; Larsen, Christopher F.; West, Michael E.; O'Neel, Shad; Pettit, Erin C.; Truffer, Martin

    2015-01-01

    The seismic signatures of calving events, i.e., calving icequakes, offer an opportunity to examine calving variability with greater precision than is available with other methods. Here using observations from Yahtse Glacier, Alaska, we describe methods to detect, locate, and characterize calving icequakes. We combine these icequake records with a coincident, manually generated record of observed calving events to develop and validate a statistical model through which we can infer iceberg sizes from the properties of calving icequakes. We find that the icequake duration is the single most significant predictor of an iceberg's size. We then apply this model to 18 months of seismic recordings and find elevated iceberg calving flux during the summer and fall and a pronounced lull in calving during midwinter. Calving flux is sensitive to semidiurnal tidal stage. Large calving events are tens of percent more likely during falling and low tides than during rising and high tides, consistent with a view that deeper water has a stabilizing influence on glacier termini. Multiple factors affect the occurrence of mechanical fractures that ultimately lead to iceberg calving. At Yahtse Glacier, seismology allows us to demonstrate that variations in the rate of submarine melt are a dominant control on iceberg calving rates at seasonal timescales. On hourly to daily timescales, tidal modulation of the normal stress against the glacier terminus reveals the nonlinear glacier response to changes in the near-terminus stress field.

  3. Conception and test of Echoes, a spectro-imager dedicated to the seismology of Jupiter

    Science.gov (United States)

    Soulat, L.; Schmider, F.-X.; Robbe-Dubois, S.; Appourchaux, T.; Gaulme, P.; Bresson, Y.; Gay, J.; Daban, J.-B.; Gouvret, C.

    2017-11-01

    Echoes is a project of a spaceborne Doppler Spectro-Imager (DSI) which has been proposed as payload to the JUICE mission project selected in the Cosmic Vision program of the European Space Agency (ESA). It is a Fourier transform spectrometer which measures phase shifts in the interference patterns induced by Doppler shifts of spectral lines reflected at the surface of the planet. Dedicated to the seismology of Jupiter, the instrument is designed to analyze the periodic movements induced by internal acoustic modes of the planet. It will allow the knowledge of the internal structure of Jupiter, in particular of the central region, which is essential for the comprehension of the scenario of the giant planets' formation. The optical design is based on a modified Mach-Zehnder interferometer operating in the visible domain and takes carefully into account the sensitivity of the optical path difference to the temperature. The instrument produces simultaneously four images in quadrature which allows the measurement of the phase without being contaminated by the continuum component of the incident light. We expect a noise level less than 1 cm2s-2µHz-1 in the frequency range [0.5 -10] mHz. In this paper, we present the prototype implemented at the Observatoire de la Côte d'Azur (OCA) in collaboration with Institut d'Astrophysique Spatiale (IAS) to study the real performances in laboratory and to demonstrate the capability to reach the required Technology Readiness Level 5.

  4. Geometry of thin liquid sheet flows

    Science.gov (United States)

    Chubb, Donald L.; Calfo, Frederick D.; Mcconley, Marc W.; Mcmaster, Matthew S.; Afjeh, Abdollah A.

    1994-01-01

    Incompresible, thin sheet flows have been of research interest for many years. Those studies were mainly concerned with the stability of the flow in a surrounding gas. Squire was the first to carry out a linear, invicid stability analysis of sheet flow in air and compare the results with experiment. Dombrowski and Fraser did an experimental study of the disintegration of sheet flows using several viscous liquids. They also detected the formulation of holes in their sheet flows. Hagerty and Shea carried out an inviscid stability analysis and calculated growth rates with experimental values. They compared their calculated growth rates with experimental values. Taylor studied extensively the stability of thin liquid sheets both theoretically and experimentally. He showed that thin sheets in a vacuum are stable. Brown experimentally investigated thin liquid sheet flows as a method of application of thin films. Clark and Dumbrowski carried out second-order stability analysis for invicid sheet flows. Lin introduced viscosity into the linear stability analysis of thin sheet flows in a vacuum. Mansour and Chigier conducted an experimental study of the breakup of a sheet flow surrounded by high-speed air. Lin et al. did a linear stability analysis that included viscosity and a surrounding gas. Rangel and Sirignano carried out both a linear and nonlinear invisid stability analysis that applies for any density ratio between the sheet liquid and the surrounding gas. Now there is renewed interest in sheet flows because of their possible application as low mass radiating surfaces. The objective of this study is to investigate the fluid dynamics of sheet flows that are of interest for a space radiator system. Analytical expressions that govern the sheet geometry are compared with experimental results. Since a space radiator will operate in a vacuum, the analysis does not include any drag force on the sheet flow.

  5. Chemically etched fiber tips for near-field optical microscopy: a process for smoother tips.

    Science.gov (United States)

    Lambelet, P; Sayah, A; Pfeffer, M; Philipona, C; Marquis-Weible, F

    1998-11-01

    An improved method for producing fiber tips for scanning near-field optical microscopy is presented. The improvement consists of chemically etching quartz optical fibers through their acrylate jacket. This new method is compared with the previous one in which bare fibers were etched. With the new process the meniscus formed by the acid along the fiber does not move during etching, leading to a much smoother surface of the tip cone. Subsequent metallization is thus improved, resulting in better coverage of the tip with an aluminum opaque layer. Our results show that leakage can be avoided along the cone, and light transmission through the tip is spatially limited to an optical aperture of a 100-nm dimension.

  6. Ice sheet hydrology from observations

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ-, Stockholm (Sweden)

    2010-11-15

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  7. Periodic folding of viscous sheets

    Science.gov (United States)

    Ribe, Neil M.

    2003-09-01

    The periodic folding of a sheet of viscous fluid falling upon a rigid surface is a common fluid mechanical instability that occurs in contexts ranging from food processing to geophysics. Asymptotic thin-layer equations for the combined stretching-bending deformation of a two-dimensional sheet are solved numerically to determine the folding frequency as a function of the sheet’s initial thickness, the pouring speed, the height of fall, and the fluid properties. As the buoyancy increases, the system bifurcates from “forced” folding driven kinematically by fluid extrusion to “free” folding in which viscous resistance to bending is balanced by buoyancy. The systematics of the numerically predicted folding frequency are in good agreement with laboratory experiments.

  8. Ice sheet hydrology from observations

    International Nuclear Information System (INIS)

    Jansson, Peter

    2010-11-01

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  9. Load Test in Sheet Pile

    OpenAIRE

    Luis Orlando Ibanez

    2016-01-01

    In this work, are discussed experiences in the use of mathematical modeling and testing in hydraulic engineering structures. For this purpose the results of load tests in sheet pile, evaluating horizontal and vertical deformations that occur in the same exposed. Comparisons between theoretical methods for calculating deformations and mathematical models based on the Finite Element Method are established. Finally, the coincidence between the numerical model and the results of the load test ful...

  10. Ohm's law for a current sheet

    Science.gov (United States)

    Lyons, L. R.; Speiser, T. W.

    1985-01-01

    The paper derives an Ohm's law for single-particle motion in a current sheet, where the magnetic field reverses in direction across the sheet. The result is considerably different from the resistive Ohm's law often used in MHD studies of the geomagnetic tail. Single-particle analysis is extended to obtain a self-consistency relation for a current sheet which agrees with previous results. The results are applicable to the concept of reconnection in that the electric field parallel to the current is obtained for a one-dimensional current sheet with constant normal magnetic field. Dissipated energy goes directly into accelerating particles within the current sheet.

  11. A novel fabrication process for out-of-plane microneedle sheets of biocompatible polymer

    Science.gov (United States)

    Han, Manhee; Hyun, Dong-Hun; Park, Hyoun-Hyang; Lee, Seung S.; Kim, Chang-Hyeon; Kim, Changgyou

    2007-06-01

    This paper presents a novel process for fabricating out-of-plane microneedle sheets of biocompatible polymer using in-plane microneedles. This process comprises four steps: (1) fabrication of in-plane microneedles using inclined UV lithography and electroforming, (2) conversion of the in-plane microneedles to an out-of-plane microneedle array, (3) fabrication of a negative PDMS mold and (4) fabrication of out-of-plane microneedle sheets of biocompatible polymer by hot embossing. The in-plane microneedles are fabricated with a sharp tip for low insertion forces and are made long to ensure sufficient penetration depth. The in-plane microneedles are converted into an out-of-plane microneedle array to increase the needle density. The negative mold is fabricated for mass-production using a polymer molding technique. The final out-of-plane microneedle sheets are produced using polycarbonate for biocompatibility by employing the hot embossing process. The height of the fabricated needles ranges from 500 to 1500 µm, and the distance between the needles is 500 to 2000 µm. The radii of curvature are approximately 2 µm, while the tip angles are in the range of 39-56°. Most of the geometrical characteristics of the out-of-plane microneedles can be freely controlled for real life applications such as drug delivery, cosmetic delivery and mesotherapy. Since it is also possible to mass-produce the microneedles, this novel process holds sufficient potential for applications in industrial fields.

  12. An Optical Fiber Bundle Sensor for Tip Clearance and Tip Timing Measurements in a Turbine Rig

    Directory of Open Access Journals (Sweden)

    María Asunción Illarramendi

    2013-06-01

    Full Text Available When it comes to measuring blade-tip clearance or blade-tip timing in turbines, reflective intensity-modulated optical fiber sensors overcome several traditional limitations of capacitive, inductive or discharging probe sensors. This paper presents the signals and results corresponding to the third stage of a multistage turbine rig, obtained from a transonic wind-tunnel test. The probe is based on a trifurcated bundle of optical fibers that is mounted on the turbine casing. To eliminate the influence of light source intensity variations and blade surface reflectivity, the sensing principle is based on the quotient of the voltages obtained from the two receiving bundle legs. A discrepancy lower than 3% with respect to a commercial sensor was observed in tip clearance measurements. Regarding tip timing measurements, the travel wave spectrum was obtained, which provides the average vibration amplitude for all blades at a particular nodal diameter. With this approach, both blade-tip timing and tip clearance measurements can be carried out simultaneously. The results obtained on the test turbine rig demonstrate the suitability and reliability of the type of sensor used, and suggest the possibility of performing these measurements in real turbines under real working conditions.

  13. Scaled multiple holes suction tip for microneurosurgery; Technical note

    Directory of Open Access Journals (Sweden)

    Abdolkarim Rahmanian, Associate Professor of Neurosurgery

    2017-12-01

    Conclusion: The new suction tip permits easy and precise adjustment of suction power in microneurosirgical operations. Our scaled 3 and 4-hole suction tip is a simple and useful device for controlling the suction power during the microneurosurgeical procedures.

  14. Tips to Help Parents Manage Their Child's Asthma Every Day

    Science.gov (United States)

    ... Tips to Help Parents Manage Their Child's Asthma Every Day Past Issues / Fall 2013 Table of Contents Asthma ... Tips to Help Parents Manage Their Child's Asthma Every Day Fall 2013 Issue: Volume 8 Number 3 Page ...

  15. Back-to-School Health Tips: Exercise and Sleep

    Science.gov (United States)

    ... up the same times each day. Keep room temperature on the cool side. A TV or computer in the bedroom can be a distraction. Read More "Back-to-School" Articles Health Tips: Immunizations / Health Tips: Exercise and ...

  16. Lifting Safety: Tips To Help Prevent Back Injuries

    Science.gov (United States)

    ... Prevent Back Injuries Lifting Safety: Tips to Help Prevent Back Injuries Share Print Back injuries are common problems at work, home, and play. They can be caused by accidents or improper lifting technique. Below are tips to ...

  17. The effect of full coverage winglets on tip leakage aerodynamics over the plane tip in a turbine cascade

    International Nuclear Information System (INIS)

    Lee, Sang Woo; Cheon, Joo Hong; Zhang, Qiang

    2014-01-01

    Highlights: • The effect of full coverage (FC) winglets on tip leakage aerodynamics is tested. • A qualitative tip gap flow model for the FC winglet is suggested. • The FC winglet of w/p = 10.55% is considered an optimal one for the plane tip. -- Abstract: The effect of full coverage (FC) winglets on tip leakage aerodynamics over the plane tip in a turbine cascade has been investigated with the variation of winglet width (w) up to w/p = 15.83% for a tip gap-to-span (chord) ratio of h/s = 1.36% (h/c = 2.0%). A qualitative tip gap flow model for the FC winglet is suggested on the bases of the near-tip surface flow visualizations. As w/p increases, the passage vortex tends to be weakened meanwhile the tip leakage vortex becomes stronger and wall-jet-like. With an increment of w/p, the mass-averaged aerodynamic loss all over the measurement plane decreases steeply up to w/p = 10.55% and then becomes almost unchanged. Thus, the FC winglet of w/p = 10.55% is considered an optimal one for the plane tip. With respect to the baseline plane tip without winglet, the maximum mass-averaged loss reduction by installing the FC winglet on the plane tip is still somewhat smaller than that by employing the cavity squealer rim on the plane tip surface

  18. Experimental formability analysis of bondal sandwich sheet

    Science.gov (United States)

    Kami, Abdolvahed; Banabic, Dorel

    2018-05-01

    Metal/polymer/metal sandwich sheets have recently attracted the interests of industries like automotive industry. These sandwich sheets have superior properties over single-layer metallic sheets including good sound and vibration damping and light weight. However, the formability of these sandwich sheets should be enhanced which requires more research. In this paper, the formability of Bondal sheet (DC06/viscoelastic polymer/DC06 sandwich sheet) was studied through different types of experiments. The mechanical properties of Bondal were determined by uniaxial tensile tests. Hemispherical punch stretching and hydraulic bulge tests were carried out to determine the forming limit diagram (FLD) of Bondal. Furthermore, cylindrical and square cup drawing tests were performed in dry and oil lubricated conditions. These tests were conducted at different blank holding forces (BHFs). An interesting observation about Bondal sheet deep drawing was obtaining of higher drawing depths at dry condition in comparison with oil-lubricated condition.

  19. Buckling and stretching of thin viscous sheets

    Science.gov (United States)

    O'Kiely, Doireann; Breward, Chris; Griffiths, Ian; Howell, Peter; Lange, Ulrich

    2016-11-01

    Thin glass sheets are used in smartphone, battery and semiconductor technology, and may be manufactured by producing a relatively thick glass slab and subsequently redrawing it to a required thickness. The resulting sheets commonly possess undesired centerline ripples and thick edges. We present a mathematical model in which a viscous sheet undergoes redraw in the direction of gravity, and show that, in a sufficiently strong gravitational field, buckling is driven by compression in a region near the bottom of the sheet, and limited by viscous resistance to stretching of the sheet. We use asymptotic analysis in the thin-sheet, low-Reynolds-number limit to determine the centerline profile and growth rate of such a viscous sheet.

  20. Facilitate, Collaborate, Educate: the Role of the IRIS Consortium in Supporting National and International Research in Seismology (Invited)

    Science.gov (United States)

    Simpson, D. W.; Beck, S. L.

    2009-12-01

    Over the twenty-five years since its founding in 1984, the IRIS Consortium has contributed in fundamental ways to change the practice and culture of research in seismology in the US and worldwide. From an original founding group of twenty-two U.S. academic institutions, IRIS membership has now grown to 114 U.S. Member Institutions, 20 Educational Affiliates and 103 Foreign Affiliates. With strong support from the National Science Foundation, additional resources provided by other federal agencies, close collaboration with the U.S. Geological Survey and many international partners, the technical resources of the core IRIS programs - the Global Seismographic Network (GSN), the Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL), the Data Management System (DMS) and Education and Outreach - have grown to become a major national and international source of experimental data for research on earthquakes and Earth structure, and a resource to support education and outreach to the public. While the primary operational focus of the Consortium is to develop and maintain facilities for the collection of seismological data for basic research, IRIS has become much more than an instrument facility. It has become a stimulus for collaboration between academic seismological programs and a focus for their interactions with national and international partners. It has helped establish the academic community as a significant contributor to the collection of data and an active participant in global research and monitoring. As a consortium of virtually all of the Earth science research institutions in the US, IRIS has helped coordinate the academic community in the development of new initiatives, such as EarthScope, to strengthen the support for science and argue for the relevance of seismology and its use in hazard mitigation. The early IRIS pioneers had the foresight to carefully define program goals and technical standards for the IRIS facilities that have stood

  1. 100 Consejos para los Padres (100 Tips for Parents).

    Science.gov (United States)

    Department of Education, Washington, DC.

    Noting that involved parents can improve their children's chances of succeeding in school, this packet of Spanish-language cards offers 100 tips created to help parents become more involved in their child's education. Following a card of general tips on becoming involved, tips are offered in the following topic areas: keeping a child alcohol,…

  2. Modular design of AFM probe with sputtered silicon tip

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Thaysen, Jacob; Bouwstra, Siebe

    2001-01-01

    of the thin films constituting the cantilever. The AFM probe has an integrated tip made of a thick sputtered silicon layer, which is deposited after the probe has been defined and just before the cantilevers are released. The tips are so-called rocket tips made by reactive ion etching. We present probes...

  3. AFM tip-sample convolution effects for cylinder protrusions

    Science.gov (United States)

    Shen, Jian; Zhang, Dan; Zhang, Fei-Hu; Gan, Yang

    2017-11-01

    A thorough understanding about the AFM tip geometry dependent artifacts and tip-sample convolution effect is essential for reliable AFM topographic characterization and dimensional metrology. Using rigid sapphire cylinder protrusions (diameter: 2.25 μm, height: 575 nm) as the model system, a systematic and quantitative study about the imaging artifacts of four types of tips-two different pyramidal tips, one tetrahedral tip and one super sharp whisker tip-is carried out through comparing tip geometry dependent variations in AFM topography of cylinders and constructing the rigid tip-cylinder convolution models. We found that the imaging artifacts and the tip-sample convolution effect are critically related to the actual inclination of the working cantilever, the tip geometry, and the obstructive contacts between the working tip's planes/edges and the cylinder. Artifact-free images can only be obtained provided that all planes and edges of the working tip are steeper than the cylinder sidewalls. The findings reported here will contribute to reliable AFM characterization of surface features of micron or hundreds of nanometers in height that are frequently met in semiconductor, biology and materials fields.

  4. Twelve tips for facilitating Millennials' learning.

    Science.gov (United States)

    Roberts, David H; Newman, Lori R; Schwartzstein, Richard M

    2012-01-01

    The current, so-called "Millennial" generation of learners is frequently characterized as having deep understanding of, and appreciation for, technology and social connectedness. This generation of learners has also been molded by a unique set of cultural influences that are essential for medical educators to consider in all aspects of their teaching, including curriculum design, student assessment, and interactions between faculty and learners.  The following tips outline an approach to facilitating learning of our current generation of medical trainees.  The method is based on the available literature and the authors' experiences with Millennial Learners in medical training.  The 12 tips provide detailed approaches and specific strategies for understanding and engaging Millennial Learners and enhancing their learning.  With an increased understanding of the characteristics of the current generation of medical trainees, faculty will be better able to facilitate learning and optimize interactions with Millennial Learners.

  5. Tip-over Prevention: Adaptive Control Development

    Science.gov (United States)

    2015-05-30

    Tip-over Prevention: Adaptive Control Development Leah Kelley Massachusetts Institute of Technology Cambridge, MA 02139 Email: lckelley@mit.edu Kurt...Papadopoulos and D. Rey, Proc. IEEE ICRA, vol.4, 1996, pp. 3111. [7] S. Ali, A. Moosavian, and K. Alipour, Robotics, Automation and Mechatronics , 2006 IEEE Conf...on, 2006, pp. 1–6. [8] K. Talke, L. Kelley, P. Longhini, and G. Catron, Proc. SPIE 9084, Unmanned Systems Technology XVI, June 2014, pp. 90 840L–11

  6. Oracle Apex reporting tips and tricks

    CERN Document Server

    Bara, George

    2013-01-01

    Take advantage of all the exciting Reporting features of Oracle Application Express 4.2. Designed for a hands-on approach, this book contains in-depth practical guidelines from George Bara, a well-known Oracle Apex expert and blogger. From Classic to Interactive Reports, Web Services and Pdf Printing, "Oracle Apex Reporting Tips & Tricks" is a must-have for all database developers that want to make the most out of the Oracle Apex reporting engine.

  7. Greenland Ice Sheet Monitoring Network (GLISN): Contributions to Science and Society

    Science.gov (United States)

    Anderson, K. R.; Bonaime, S.; Clinton, J. F.; Dahl-Jensen, T.; Debski, W. M.; Giardini, D.; Govoni, A.; Kanao, M.; Larsen, T. B.; Lasocki, S.; Lee, W. S.; McCormack, D. A.; Mykkeltveit, S.; Nettles, M.; Stutzmann, E.; Strollo, A.; Sweet, J. R.; Tsuboi, S.; Vallee, M.

    2017-12-01

    The Greenland Ice Sheet Monitoring Network (GLISN) is a broadband, multi-use seismological network, enhanced by selected geodetic observations, designed with the capability to allow researchers to understand the changes currently occurring in the Arctic, and with the operational characteristics necessary to enable response to those changes as understanding improves. GLISN was established through an international collaboration, with 10 nations coordinating their efforts to develop the current 34-station observing network during the last eight years. All of the data collected are freely and openly available in near-real time. The network was designed to transform the community capability for recording, analysis, and interpretation of seismic signals generated by discrete events in Greenland and the Arctic, as well as those traversing the region. Data from the network support a wide range of uses, including estimation of the properties of the solid Earth that control isostatic adjustment rates and set key boundary conditions for ice-sheet evolution; analysis of tectonic earthquakes throughout Greenland and the Arctic; study of the seismic signals associated with large calving events and changing glacier dynamics; and variations in ice and snow properties within the Greenland Ice Sheet. Recordings from the network have also provided invaluable data for rapid evaluation and understanding of the devastating landslide and tsunami that occurred near Nuugaatsiaq, Greenland, in June, 2017. The GLISN strategy of maximizing data quality from a network of approximately evenly distributed stations, delivering data in near-real time, and archiving a continuous data stream easily accessible to researchers, allows continuous discovery of new uses while also facilitating the generation of data products, such as catalogs of tectonic and glacial earthquakes and GPS-based estimates of snow height, that allow for assessment of change over time.

  8. Dispel4py: An Open-Source Python library for Data-Intensive Seismology

    Science.gov (United States)

    Filgueira, Rosa; Krause, Amrey; Spinuso, Alessandro; Klampanos, Iraklis; Danecek, Peter; Atkinson, Malcolm

    2015-04-01

    Scientific workflows are a necessary tool for many scientific communities as they enable easy composition and execution of applications on computing resources while scientists can focus on their research without being distracted by the computation management. Nowadays, scientific communities (e.g. Seismology) have access to a large variety of computing resources and their computational problems are best addressed using parallel computing technology. However, successful use of these technologies requires a lot of additional machinery whose use is not straightforward for non-experts: different parallel frameworks (MPI, Storm, multiprocessing, etc.) must be used depending on the computing resources (local machines, grids, clouds, clusters) where applications are run. This implies that for achieving the best applications' performance, users usually have to change their codes depending on the features of the platform selected for running them. This work presents dispel4py, a new open-source Python library for describing abstract stream-based workflows for distributed data-intensive applications. Special care has been taken to provide dispel4py with the ability to map abstract workflows to different platforms dynamically at run-time. Currently dispel4py has four mappings: Apache Storm, MPI, multi-threading and sequential. The main goal of dispel4py is to provide an easy-to-use tool to develop and test workflows in local resources by using the sequential mode with a small dataset. Later, once a workflow is ready for long runs, it can be automatically executed on different parallel resources. dispel4py takes care of the underlying mappings by performing an efficient parallelisation. Processing Elements (PE) represent the basic computational activities of any dispel4Py workflow, which can be a seismologic algorithm, or a data transformation process. For creating a dispel4py workflow, users only have to write very few lines of code to describe their PEs and how they are

  9. Insights on the lithospheric structure of the Zagros mountain belt from seismological data analysis

    Science.gov (United States)

    Paul, A.; Kaviani, A.; Vergne, J.; Hatzfeld, D.; Mokhtari, M.

    2003-04-01

    As part of a French-Iranian collaboration, we installed a temporary seismological network across the Zagros for 4.5 months in 2000-2001 to investigate the lithospheric structure of the mountain belt. The network included 65 stations located along a 600-km long line (average spacing of ˜10 km) from the coast of the Persian Gulf to the stable block of Central Iran. A migrated depth cross-section computed from radial receiver functions displays clear P-to-S conversions at the Moho beneath most of the profile. The average Moho depth is 45 to 50 km beneath the folded belt. It deepens rather abruptly beneath the suture zone of the MZT (Main Zagros Thrust) and the Sanandaj-Sirjan (SS) metamorphic zone. The maximum crustal thickness of ˜65 km is reached 50 km NE of the surface trace of the MZT. The region of over-thickened crust is shifted to the NE with respect to the areas of highest elevations and the strongest negative Bouguer anomaly. To the NE, the crust of the block of Central Iran is 40-km thick on average. Two patches of Ps converted energy can be seen below the Moho in the northern half of the transect that cannot be attributed to multiple reflections. Teleseismic P residual travel time curves display lateral variations as large as 1.5 s with both long (faster arrivals in the SW than in the NE) and short-scale variations (in the MZT region). They were inverted for variations of P wave velocity with the ACH technique. The crustal layer exhibits rather strong lateral variations of Vp with lower velocities under the MZT and the Urumieh-Dokhtar magmatic assemblage, and faster velocities under the SS zone. In the mantle, a clear difference appears between the faster P wave velocities of the Arabian craton and the relatively lower velocities of the mantle of Central Iran.

  10. QuakeML: Status of the XML-based Seismological Data Exchange Format

    Science.gov (United States)

    Euchner, Fabian; Schorlemmer, Danijel; Kästli, Philipp; Quakeml Working Group

    2010-05-01

    QuakeML is an XML-based data exchange standard for seismology that is in its fourth year of active community-driven development. The current release (version 1.2) is based on a public Request for Comments process that included contributions from ETH, GFZ, USC, SCEC, USGS, IRIS DMC, EMSC, ORFEUS, GNS, ZAMG, BRGM, Nanometrics, and ISTI. QuakeML has mainly been funded through the EC FP6 infrastructure project NERIES, in which it was endorsed as the preferred data exchange format. Currently, QuakeML services are being installed at several institutions around the globe, including EMSC, ORFEUS, ETH, Geoazur (Europe), NEIC, ANSS, SCEC/SCSN (USA), and GNS Science (New Zealand). Some of these institutions already provide QuakeML earthquake catalog web services. Several implementations of the QuakeML data model have been made. QuakePy, an open-source Python-based seismicity analysis toolkit using the QuakeML data model, is being developed at ETH. QuakePy is part of the software stack used in the Collaboratory for the Study of Earthquake Predictability (CSEP) testing center installations, developed by SCEC. Furthermore, the QuakeML data model is part of the SeisComP3 package from GFZ Potsdam. QuakeML is designed as an umbrella schema under which several sub-packages are collected. The present scope of QuakeML 1.2 covers a basic description of seismic events including picks, arrivals, amplitudes, magnitudes, origins, focal mechanisms, and moment tensors. Work on additional packages (macroseismic information, seismic inventory, and resource metadata) has been started, but is at an early stage. Contributions from the community that help to widen the thematic coverage of QuakeML are highly welcome. Online resources: http://www.quakeml.org, http://www.quakepy.org

  11. Enhancing Outreach using Social Networks at the National Seismological Network of Costa Rica

    Science.gov (United States)

    Linkimer, L.; Lücke, O. H.

    2014-12-01

    Costa Rica has a very high seismicity rate and geological processes are part of everyday life. Traditionally, information about these processes has been provided by conventional mass media (television and radio). However, due to the new trends in information flow a new approach towards Science Education is necessary for transmitting knowledge from scientific research for the general public in Costa Rica. Since 1973, the National Seismological Network of Costa Rica (RSN: UCR-ICE) studies the seismicity and volcanic activity in the country. In this study, we describe the different channels to report earthquake information that the RSN is currently using: email, social networks, and a website, as well as the development of a smartphone application. Since the RSN started actively participating in Social Networks, an increase in awareness in the general public has been noticed particularly regarding felt earthquakes. Based on this trend, we have focused on enhancing public outreach through Social Media. We analyze the demographics and geographic distribution of the RSN Facebook Page, the growth of followers, and the significance of their feedback for reporting intensity data. We observe that certain regions of the country have more Facebook activity, although those regions are not the most populated nor have a high Internet connectivity index. We interpret this pattern as the result of a higher awareness to geological hazards in those specific areas. We noticed that the growth of RSN users on Facebook has a strong correlation with the seismic events as opposed to Twitter that displays a steady growth with no clear correlations with specific seismic events. We see the Social Networks as opportunities to engage non-science audiences and encourage the population to participate in reporting seismic observations, thus providing intensity data. With the increasing access to Internet from mobile phones in Costa Rica, we see this approach to science education as an opportunity

  12. Seismological studies carried out by the CEA in connection with the safety of nuclear sites

    International Nuclear Information System (INIS)

    Barbreau, A.; Ferrieux, H.; Mohammadioun, B.

    1975-01-01

    In order to evaluate the seismic risk at nuclear sites, the Department of Nuclear Safety of the French Atomic Energy Commission (CEA) has been conducting a programme of seismological studies for several years past. This programme is aimed at acquiring a better knowledge of seismic phenomena, in particular the spectral distribution of the energy of earthquakes, considered to be the only correct approach to the problem of earthquake protection, as well as a better knowledge of the seismic activity of the areas surrounding nuclear sites. The authors propose defining the design spectrum of the site on the basis of the probable energy at the source, the distance from the epicentre and the transfer function of the geological formations. The need - for the purpose of defining this spectrum - to acquire data on the characteristics of French earthquakes and on regional seismicity led the Department of Nuclear Safety to set up a network of seismic stations. It now has an observatory at the Cadarache Nuclear Research Centre and mobile stations with automatic magnetic recording for studying aftershock sequences and the activity of faults in the vicinity of nuclear sites, and for making the measurements necessary to calculate the transfer functions. With this equipment it was possible to record six aftershocks of the Oleron earthquake on 7 September 1972 close to the epicentre, and to calculate the spectra therefrom. The latter contained a lot of high frequencies, which is in agreement with the data obtained from other sources for earthquakes of low energy. The synthetic spectra calculated on the basis of one magnitude and one distance are in good agreement with the spectra obtained experimentally

  13. Seismological investigation of September 09 2016, North Korea underground nuclear test

    Directory of Open Access Journals (Sweden)

    H. Gaber

    2017-12-01

    Full Text Available On Sep. 9, 2016, a seismic event of mb 5.3 took place in North Korea. This event was reported as a nuclear test. In this study, we applied a number of discriminant techniques that facilitate the ability to distinguish between explosions and earthquakes on the Korean Peninsula. The differences between explosions and earthquakes are due to variation in source dimension, epicenter depth and source mechanism, or a collection of them. There are many seismological differences between nuclear explosions and earthquakes, but not all of them are detectable at large distances or are appropriate to each earthquake and explosion. The discrimination methods used in the current study include the seismic source location, source depth, the differences in the frequency contents, complexity versus spectral ratio and Ms-mb differences for both earthquakes and explosions. Sep. 9, 2016, event is located in the region of North Korea nuclear test site at a zero depth, which is likely to be a nuclear explosion. Comparison between the P wave spectra of the nuclear test and the Sep. 8, 2000, North Korea earthquake, mb 4.9 shows that the spectrum of both events is nearly the same. The results of applying the theoretical model of Brune to P wave spectra of both explosion and earthquake show that the explosion manifests larger corner frequency than the earthquake, reflecting the nature of the different sources. The complexity and spectral ratio were also calculated from the waveform data recorded at a number of stations in order to investigate the relation between them. The observed classification percentage of this method is about 81%. Finally, the mb:Ms method is also investigated. We calculate mb and Ms for the Sep. 9, 2016, explosion and compare the result with the mb: Ms chart obtained from the previous studies. This method is working well with the explosion. Keywords: Discrimination, Seismic source location, Brune model, Spectral parameters, Complexity method, Mb: Ms

  14. High-rate multi-GNSS: what does it mean to seismology?

    Science.gov (United States)

    Geng, J.

    2017-12-01

    GNSS precise point positioning (PPP) is capable of measuring centimeter-level positions epoch by epoch at a single station, and is thus treasured in tsunami/earthquake early warning where static displacements in the near field are critical to rapidly and reliably determining the magnitude of destructive events. However, most operational real-time PPP systems at present rely on only GPS data. The deficiency of such systems is that the high reliability and availability of precise displacements cannot be maintained continuously in real time, which is however a crucial requirement for disaster resistance and response. Multi-GNSS, including GLONASS, BeiDou, Galileo and QZSS other than only GPS, can be a solution to this problem because much more satellites per epoch (e.g. 30-40) will be available. In this case, positioning failure due to data loss or blunders can be minimized, and on the other hand, positioning initializations can be accelerated to a great extent since the satellite geometry for each epoch will be enhanced enormously. We established a prototype real-time multi-GNSS PPP service based on Asia-Pacific real-time network which can collect and stream high-rate data from all five navigation systems above. We estimated high-rate satellite clock corrections and enabled undifferenced ambiguity fixing for multi-GNSS, which therefore ensures high availability and reliability of precise displacement estimates in contrast to GPS-only systems. We will report how we can benefit from multi-GNSS for seismology, especially the noise characteristics of high-rate and sub-daily displacements. We will also use storm surge loading events to demonstrate the contribution of multi-GNSS to sub-daily transient signals.

  15. Young solar-type stars evolution: the lithium and seismology contributions

    International Nuclear Information System (INIS)

    Piau, Laurent Eric

    2001-01-01

    This PhD thesis is devoted to young low-mass stars. We modeled many of them since their formation until the solar age covering the range between 0.65 and 1.4 solar masses and metallicity values ranging from -0.1 to 0.1 dex. The theoretical computations are related to observations in nearby open-clusters: Hyades, Pleiades... This comparison demonstrates that the lithium evolution is still poorly understood in such stars. In stellar interiors, this nuclide is destroyed by nuclear processes at low temperatures. Its surface abundance evolution traduces mixing phenomena between surface and deeper layers and therefore allows a direct insight into stellar structure and evolution. Both of which depend on microscopic and macroscopic physical phenomena whose effects we systematically examine. As regards microphysics we mainly concentrate upon changes in metallicity, in distribution among metals and their consequences on stellar opacity. We also address atmospheric models while the star still lies close to its Hayashi track. Accretion and convective parameters are the macroscopic phenomena we address during pre-main sequence. The rotational effects are considered along the entire evolution including the much realistic rotation laws. The last part of this PhD thesis makes use of seismology. Today this Discipline allows direct probing of the solar internal structure and motions. Its future application in the realm of stars will substantially improve their understanding. We derive here some relevant seismic variables for the understanding of stellar evolution. Then we show how this powerful tool permits to determine fundamental stellar parameters such as the mass or the helium fraction. (author) [fr

  16. Antarctic climate and ice-sheet configuration during the early Pliocene interglacial at 4.23 Ma

    Directory of Open Access Journals (Sweden)

    N. R. Golledge

    2017-07-01

    Full Text Available The geometry of Antarctic ice sheets during warm periods of the geological past is difficult to determine from geological evidence, but is important to know because such reconstructions enable a more complete understanding of how the ice-sheet system responds to changes in climate. Here we investigate how Antarctica evolved under orbital and greenhouse gas conditions representative of an interglacial in the early Pliocene at 4.23 Ma, when Southern Hemisphere insolation reached a maximum. Using offline-coupled climate and ice-sheet models, together with a new synthesis of high-latitude palaeoenvironmental proxy data to define a likely climate envelope, we simulate a range of ice-sheet geometries and calculate their likely contribution to sea level. In addition, we use these simulations to investigate the processes by which the West and East Antarctic ice sheets respond to environmental forcings and the timescales over which these behaviours manifest. We conclude that the Antarctic ice sheet contributed 8.6 ± 2.8 m to global sea level at this time, under an atmospheric CO2 concentration identical to present (400 ppm. Warmer-than-present ocean temperatures led to the collapse of West Antarctica over centuries, whereas higher air temperatures initiated surface melting in parts of East Antarctica that over one to two millennia led to lowering of the ice-sheet surface, flotation of grounded margins in some areas, and retreat of the ice sheet into the Wilkes Subglacial Basin. The results show that regional variations in climate, ice-sheet geometry, and topography produce long-term sea-level contributions that are non-linear with respect to the applied forcings, and which under certain conditions exhibit threshold behaviour associated with behavioural tipping points.

  17. Antarctic climate and ice-sheet configuration during the early Pliocene interglacial at 4.23 Ma

    Science.gov (United States)

    Golledge, Nicholas R.; Thomas, Zoë A.; Levy, Richard H.; Gasson, Edward G. W.; Naish, Timothy R.; McKay, Robert M.; Kowalewski, Douglas E.; Fogwill, Christopher J.

    2017-07-01

    The geometry of Antarctic ice sheets during warm periods of the geological past is difficult to determine from geological evidence, but is important to know because such reconstructions enable a more complete understanding of how the ice-sheet system responds to changes in climate. Here we investigate how Antarctica evolved under orbital and greenhouse gas conditions representative of an interglacial in the early Pliocene at 4.23 Ma, when Southern Hemisphere insolation reached a maximum. Using offline-coupled climate and ice-sheet models, together with a new synthesis of high-latitude palaeoenvironmental proxy data to define a likely climate envelope, we simulate a range of ice-sheet geometries and calculate their likely contribution to sea level. In addition, we use these simulations to investigate the processes by which the West and East Antarctic ice sheets respond to environmental forcings and the timescales over which these behaviours manifest. We conclude that the Antarctic ice sheet contributed 8.6 ± 2.8 m to global sea level at this time, under an atmospheric CO2 concentration identical to present (400 ppm). Warmer-than-present ocean temperatures led to the collapse of West Antarctica over centuries, whereas higher air temperatures initiated surface melting in parts of East Antarctica that over one to two millennia led to lowering of the ice-sheet surface, flotation of grounded margins in some areas, and retreat of the ice sheet into the Wilkes Subglacial Basin. The results show that regional variations in climate, ice-sheet geometry, and topography produce long-term sea-level contributions that are non-linear with respect to the applied forcings, and which under certain conditions exhibit threshold behaviour associated with behavioural tipping points.

  18. Strontium-90 fluoride data sheet

    Energy Technology Data Exchange (ETDEWEB)

    Fullam, H.T.

    1981-06-01

    This report is a compilation of available data and appropriate literature references on the properties of strontium-90 fluoride and nonradioactive strontium fluoride. The objective of the document is to compile in a single source pertinent data to assist potential users in the development, licensing, and use of /sup 90/SrF/sub 2/-fueled radioisotope heat sources for terrestrial power conversion and thermal applications. The report is an update of the Strontium-90 Fluoride Data Sheet (BNWL-2284) originally issued in April 1977.

  19. Vietnamese Hurricane Response Fact Sheets

    Science.gov (United States)

    Các tờ dữ kiện được cung cấp nơi đây mô tả vai trò của EPA trong việc đáp ứng với bão và cách các chương trình cụ thể cung cấp sự hỗ trợ. The Vietnamese fact sheets provided here describe EPA's role in a hurricane response.

  20. Towards a tipping point in responding to change: rising costs, fewer options for Arctic and global societies.

    Science.gov (United States)

    Huntington, Henry P; Goodstein, Eban; Euskirchen, Eugénie

    2012-02-01

    Climate change incurs costs, but government adaptation budgets are limited. Beyond a certain point, individuals must bear the costs or adapt to new circumstances, creating political-economic tipping points that we explore in three examples. First, many Alaska Native villages are threatened by erosion, but relocation is expensive. To date, critically threatened villages have not yet been relocated, suggesting that we may already have reached a political-economic tipping point. Second, forest fires shape landscape and ecological characteristics in interior Alaska. Climate-driven changes in fire regime require increased fire-fighting resources to maintain current patterns of vegetation and land use, but these resources appear to be less and less available, indicating an approaching tipping point. Third, rapid sea level rise, for example from accelerated melting of the Greenland ice sheet, will create a choice between protection and abandonment for coastal regions throughout the world, a potential global tipping point comparable to those now faced by Arctic communities. The examples illustrate the basic idea that if costs of response increase more quickly than available resources, then society has fewer and fewer options as time passes.

  1. The development of fabrication techniques for europia/iron cermet tips for coarse-control arms in DIDO and PLUTO

    International Nuclear Information System (INIS)

    Moore, D.A.; Tarrant, E.A.

    1980-11-01

    The applicability of cermet-fabrication techniques to the production of europia/iron cermets for use as coarse-control arm tips in the materials test reactors DIDO and PLUTO has been investigated. Spheroids of europia were prepared by a dry agglomeration process. These were sintered, dispersed in iron powder and pressed into plates; the plates were then sintered to densify the iron matrix. These stages were optimised to produce a strong cermet with a europia density of >= 2.75 g/cm 3 . The uniformity of distribution of the absorber particles was confirmed by radiography, and adequate neutron-absorption worth by measurements carried out in the GLEEP reactor. An outline flow sheet has been prepared for the manufacture of europia/iron cermet plates suitable for use in the tips of DIDO and PLUTO coarse-control arms. (author)

  2. Magnetic elements for switching magnetization magnetic force microscopy tips

    International Nuclear Information System (INIS)

    Cambel, V.; Elias, P.; Gregusova, D.; Martaus, J.; Fedor, J.; Karapetrov, G.; Novosad, V.

    2010-01-01

    Using combination of micromagnetic calculations and magnetic force microscopy (MFM) imaging we find optimal parameters for novel magnetic tips suitable for switching magnetization MFM. Switching magnetization MFM is based on two-pass scanning atomic force microscopy with reversed tip magnetization between the scans. Within the technique the sum of the scanned data with reversed tip magnetization depicts local atomic forces, while their difference maps the local magnetic forces. Here we propose the design and calculate the magnetic properties of tips suitable for this scanning probe technique. We find that for best performance the spin-polarized tips must exhibit low magnetic moment, low switching fields, and single-domain state at remanence. The switching field of such tips is calculated and optimum shape of the Permalloy elements for the tips is found. We show excellent correspondence between calculated and experimental results for Py elements.

  3. Continuum damage mechanics analysis of crack tip zone

    International Nuclear Information System (INIS)

    Yinchu, L.; Jianping, Z.

    1989-01-01

    The crack tip field and its intensity factor play an important role in fracture mechanics. Generally, the damage such as microcracks, microvoids etc. will initiate and grow in materials as the cracked body is subjected to external loadings, especially in the crack tip zone. The damage evolution will load to the crack tip damage field and the change of the stress, strain and displacement fields of cracks tip zone. In this paper, on the basis of continuum damage mechanics, the authors have derived the equations which the crack tip field and its intensity factor must satisfy in a loading process, calculated the angle distribution curves of stress, strain and displacement fields in a crack tip zone and have compared them with the corresponding curves of HRR field and linear elastic field in undamaged materials. The equations of crack tip field intensity factors have been solved and its solutions give the variation of the field intensity factors with the loading parameter

  4. Arctic tipping points in an Earth system perspective.

    Science.gov (United States)

    Wassmann, Paul; Lenton, Timothy M

    2012-02-01

    We provide an introduction to the volume The Arctic in the Earth System perspective: the role of tipping points. The terms tipping point and tipping element are described and their role in current science, general debates, and the Arctic are elucidated. From a wider perspective, the volume focuses upon the role of humans in the Arctic component of the Earth system and in particular the envelope for human existence, the Arctic ecosystems. The Arctic climate tipping elements, the tipping elements in Arctic ecosystems and societies, and the challenges of governance and anticipation are illuminated through short summaries of eight publications that derive from the Arctic Frontiers conference in 2011 and the EU FP7 project Arctic Tipping Points. Then some ideas based upon resilience thinking are developed to show how wise system management could ease pressures on Arctic systems in order to keep them away from tipping points.

  5. AI applications in sheet metal forming

    CERN Document Server

    Hussein, Hussein

    2017-01-01

    This book comprises chapters on research work done around the globe in the area of artificial intelligence (AI) applications in sheet metal forming. The first chapter offers an introduction to various AI techniques and sheet metal forming, while subsequent chapters describe traditional procedures/methods used in various sheet metal forming processes, and focus on the automation of those processes by means of AI techniques, such as KBS, ANN, GA, CBR, etc. Feature recognition and the manufacturability assessment of sheet metal parts, process planning, strip-layout design, selecting the type and size of die components, die modeling, and predicting die life are some of the most important aspects of sheet metal work. Traditionally, these activities are highly experience-based, tedious and time consuming. In response, researchers in several countries have applied various AI techniques to automate these activities, which are covered in this book. This book will be useful for engineers working in sheet metal industri...

  6. Dynamics of Radially Expanding Liquid Sheets

    Science.gov (United States)

    Majumdar, Nayanika; Tirumkudulu, Mahesh S.

    2018-04-01

    The process of atomization often involves ejecting thin liquid sheets at high speeds from a nozzle that causes the sheet to flap violently and break up into fine droplets. The flapping of the liquid sheet has long been attributed to the sheet's interaction with the surrounding gas phase. Here, we present experimental evidence to the contrary and show that the flapping is caused by the thinning of the liquid sheet as it spreads out from the nozzle exit. The measured growth rates of the waves agree remarkably well with the predictions of a recent theory that accounts for the sheet's thinning but ignores aerodynamic interactions. We anticipate these results to not only lead to more accurate predictions of the final drop-size distribution but also enable more efficient designs of atomizers.

  7. Unzip instabilities: Straight to oscillatory transitions in the cutting of thin polymer sheets

    Science.gov (United States)

    Reis, P. M.; Kumar, A.; Shattuck, M. D.; Roman, B.

    2008-06-01

    We report an experimental investigation of the cutting of a thin brittle polymer sheet with a blunt tool. It was recently shown that the fracture path becomes oscillatory when the tool is much wider than the sheet thickness. Here we uncover two novel transitions from straight to oscillatory fracture by varying either the tilt angle of the tool or the speed of cutting, respectively. We denote these by angle and speed unzip instabilities and analyze them by quantifying both the dynamics of the crack tip and the final shapes of the fracture paths. Moreover, for the speed unzip instability, the straight crack lip obtained at low speeds exhibits out-of-plane buckling undulations (as opposed to being flat above the instability threshold) suggesting a transition from ductile to brittle fracture.

  8. Shape Optimization of Swimming Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  9. Magnetic properties of sheet silicates

    International Nuclear Information System (INIS)

    Ballet, O.; Coey, J.M.D.

    1982-01-01

    Susceptibility, magnetisation and Moessbauer measurements are reported for a representative selection of 2:1 layer phyllosilicates. Eight samples from the mica, vermiculite and smectite groups include examples diluted in iron which are paramagnetic at all temperatures, as well as iron-rich silicates which order magnetically below 10 K. Anisotropic susceptibility of crystals of muscovite, biotite and vermiculite is quantitatively explained with a model where the Fe 2+ ions lie in sites of effective trigonal symmetry, the trigonal axis lying normal to the sheets. The ferrous ground state is an orbital singlet. Ferric iron gives an isotropic contribution to the susceptibility. Fe 2+ -Fe 2+ exchange interactions are ferromagnetic with Gapprox. equal to2 K, whereas Fe 3+ -Fe 3+ coupling is antiferromagnetic in the purely ferric minerals. A positive paramagnetic Curie temperature for glauconite may be attributable to Fe 2+ → Fe 3+ charge transfer. Magnetic order was found to set in inhomogeneously for glauconite at 1-7 K. One biotite sample showed an antiferromagnetic transition at Tsub(N) = 7 K marked by a well-defined susceptibility maximum. Its magnetic structure, consisting of ferromagnetic sheets with moments in their planes coupled antiferromagnetically by other, weak interactions, resembles that found earlier for the 1:1 mineral greenalite. (orig.)

  10. Weld Repair of Thin Aluminum Sheet

    Science.gov (United States)

    Beuyukian, C. S.; Mitchell, M. J.

    1986-01-01

    Weld repairing of thin aluminum sheets now possible, using niobium shield and copper heat sinks. Refractory niobium shield protects aluminum adjacent to hole, while copper heat sinks help conduct heat away from repair site. Technique limits tungsten/inert-gas (TIG) welding bombardment zone to melt area, leaving surrounding areas around weld unaffected. Used successfully to repair aluminum cold plates on Space Shuttle, Commercial applications, especially in sealing fractures, dents, and holes in thin aluminum face sheets or clad brazing sheet in cold plates, heat exchangers, coolers, and Solar panels. While particularly suited to thin aluminum sheet, this process also used in thicker aluminum material to prevent surface damage near weld area.

  11. Predicting Pulsar Scintillation from Refractive Plasma Sheets

    Science.gov (United States)

    Simard, Dana; Pen, Ue-Li

    2018-05-01

    The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along sheets in the ionized interstellar medium, such as those due to Alfvén waves propagating along current sheets. If these sheets are closely aligned to our line-of-sight to the pulsar, high bending angles arise at the wave crests and a selection effect causes alignment of images produced at different crests, similar to grazing reflection off of a lake. Using geometric optics, we develop a simple parameterized model of these corrugated sheets that can be constrained with a single observation and that makes observable predictions for variations in the scintillation of the pulsar over time and frequency. This model reveals qualitative differences between lensing from overdense and underdense corrugated sheets: Only if the sheet is overdense compared to the surrounding interstellar medium can the lensed images be brighter than the line-of-sight image to the pulsar, and the faint lensed images are closer to the pulsar at higher frequencies if the sheet is underdense, but at lower frequencies if the sheet is overdense.

  12. Using seismology to raise science awareness in kindergarten and elementary levels, with the help of high school students

    Science.gov (United States)

    Rocha, F. L.; Silveira, G. M.; Moreira, G.; Afonso, I. P.; Maciel, B. A. P. C.; Melo, M. O.; Neto, R. P.; Gonçalves, M.; Marques, G.; Hartmann, R. P.

    2014-12-01

    Teaching students, aged from 4 up to 18 years old, is a challenging task. It continuously implies new strategies and new subjects adapted to all of them. This is even more evident, when we have to teach natural-hazards scientific aspects and safe attitudes toward risk. We often see that most of the high-school students (16 -18 years old) are not motivated for extra-curricular activities implying science and/or behaviours changes. But, they have a very positive response when we give them some responsibility. On top of that, we also realised that young children are quite receptive to the involvement of older students in the school environment Taking this into consideration, our project use the k12 students to prepare scientific activities and subjects, based in questions, which they need to answer themselves. The students need to answer those questions and, only then, adapt and teach the right answers to the different school-levels. With this approach, we challenged the students to solve three questions: How to use a SEP seismometer at school, and its data? How to set up a shaking table? How to introduce waves and vibrations contents to all ages of students? During the project they developed many science skills, and worked in straight cooperation with teachers, the parents association and the seismology research group at Instituto Dom Luíz. As a result, it was possible to reach all school students with the help of the k-12 ones. This is an outcome of the project W-Shake, a Parents-in-Science Initiative to promote the study of seismology and related subjects. This project, supported by the Portuguese "Ciência Viva" program, results from a direct cooperation between the parents association, science school-teachers and the seismology research group at Instituto Dom Luíz.

  13. The fate of the Greenland Ice Sheet in a geoengineered, high CO2 world

    International Nuclear Information System (INIS)

    Irvine, Peter J; Lunt, Daniel J; Stone, Emma J; Ridgwell, Andy

    2009-01-01

    Solar radiation management (SRM) geoengineering has been proposed as one means of helping avoid the occurrence of dangerous climate change and undesirable state transitions ('tipping points') in the Earth system. The irreversible melting of the Greenland Ice Sheet is a case in point-a state transition that could occur as a result of CO 2 -driven elevated global temperatures, and one leading to potentially catastrophic sea-level rise. SRM schemes such as the creation of a 'sunshade' or injection of sulfate aerosols into the stratosphere could reduce incoming solar radiation, and in theory balance, in a global mean, the greenhouse warming resulting from elevated concentrations of CO 2 in the atmosphere. Previous work has highlighted that a geoengineered world would have: warming towards the poles, cooling in the tropics, and a reduction in the global hydrological cycle, which may have important implications for the Greenland Ice Sheet. Using a fully coupled global climate model in conjunction with an ice sheet model, we assess the consequences for the mass balance of the Greenland Ice Sheet of the reorganization of climate patterns by the combination of high CO 2 and geoengineering. We find that Greenland surface temperature and precipitation anomalies, compared to the pre-industrial situation, decrease almost linearly with increasing levels of SRM geoengineering, but that these combine to create a highly non-linear response of the ice sheet. The substantial melting of the Greenland Ice Sheet predicted for four times pre-industrial CO 2 levels is prevented in our model with only a partial application of SRM, and hence without having to fully restore the global average temperature back to pre-industrial levels. This suggests that the degree of SRM geoengineering required to mitigate the worst impacts of greenhouse warming, such as sea-level rise, need not be as extensive as generally assumed.

  14. Microstructure and Mechanical Performance of Friction Stir Spot-Welded Aluminum-5754 Sheets

    Science.gov (United States)

    Pathak, N.; Bandyopadhyay, K.; Sarangi, M.; Panda, Sushanta Kumar

    2013-01-01

    Friction stir spot welding (FSSW) is a recent trend of joining light-weight sheet metals while fabricating automotive and aerospace body components. For the successful application of this solid-state welding process, it is imperative to have a thorough understanding of the weld microstructure, mechanical performance, and failure mechanism. In the present study, FSSW of aluminum-5754 sheet metal was tried using tools with circular and tapered pin considering different tool rotational speeds, plunge depths, and dwell times. The effects of tool design and process parameters on temperature distribution near the sheet-tool interface, weld microstructure, weld strength, and failure modes were studied. It was found that the peak temperature was higher while welding with a tool having circular pin compared to tapered pin, leading to a bigger dynamic recrystallized stir zone (SZ) with a hook tip bending towards the upper sheet and away from the keyhole. Hence, higher lap shear separation load was observed in the welds made from circular pin compared to those made from tapered pin. Due to influence of size and hardness of SZ on crack propagation, three different failure modes of weld nugget were observed through optical cross-sectional micrograph and SEM fractographs.

  15. Eagle Pass Jr. High Seismology Team: Strategies for Engaging Middle School "At-Risk" Students in Authentic Research

    Science.gov (United States)

    Brunt, M. R.; Ellins, K. K.; Frohlich, C. A.

    2011-12-01

    In 2008, during my participation in the NSF-sponsored Texas Earth & Space Science (TXESS) Revolution professional development program, I was awarded an AS-1 seismograph through IRIS's Seismographs in Schools Program. This program serves to create an international educational seismic network that allows teachers across the country and around the world to share seismic data in real-time using online tools, classroom activities, and technical support documents for seismic instruments. Soon after receiving my AS-1, I founded and began sponsoring the Eagle Pass Jr. High Seismology Team which consists of selected 7th and 8th grade students. Eagle Pass Jr. High is a Title 1 school that serves a predominantly "at-risk" Hispanic population. We meet after school once a week to learn about earthquakes, seismic waves, analyze recorded seismic event data using computer software programming, and correspond with other students from schools around the country. This team approach has been well received by fellow TXESS Revolution teachers with AS-1 seismographs and will be implemented by David Boyd, STEM coordinator for Williams Preparatory Academy in Dallas, Texas this fall 2011. All earthquakes recorded by our seismograph station (EPTX), which has remained online and actively recording seismic data since 2008, are catalogued and then plotted on a large world map displayed on my classroom wall. A real-time seismogram image updates every five minutes and along with all earthquakes recorded since installation can be viewed on our webpage http://www.iris.edu/hq/ssn/schools/view/eptx. During the 2010-2011 school year, my seismology team and I participated in an earthquake research study led by Dr. Cliff Frohlich at the Institute for Geophysics. The study examined seismograms and felt reports for the 25 April 2010 Alice, Texas, earthquake, in order to investigate its possible connection to oil and gas production in the Stratton oil and gas field. A research paper detailing our findings

  16. Numerical Simulation of LVAD Inflow Cannulas with Different Tip

    Directory of Open Access Journals (Sweden)

    Guang-Mao Liu

    2012-01-01

    Full Text Available The tip structure of LVAD inflow cannula is one of major factors to lead adverse events such as thrombosis and suction leading to obstruction. In this research, four kinds of tips that had been used in inflow cannulas were selected and designed. The flow field of the four inflow cannulas inserted into the apex of left ventricle (LV was numerically computed by computational fluid dynamics. The flow behavior was analyzed in order to compare the blood compatibility and suction in left ventricle and cannulas after the inflow cannulas with different tips were inserted to the apex of LV. The results showed that the cannula tip structure affected the LVAD performance. Among these four cannulas, the trumpet-tipped inflow cannula owned the best performance in smooth flow velocity distribution without backflow or low-velocity flow so that it was the best in blood compatibility. Nevertheless, the caged tipped cannula was the worst in blood compatibility. And the blunt-tipped and beveled tipped inflow cannulas may obstruct more easily than trumpet and caged tipped inflow cannulas because of their shape. The study indicated that the trumpet tip was the most preferable for the inflow cannula of long-term LVAD.

  17. Relocalization of human chromatin remodeling cofactor TIP48 in mitosis

    International Nuclear Information System (INIS)

    Sigala, Barbara; Edwards, Mina; Puri, Teena; Tsaneva, Irina R.

    2005-01-01

    TIP48 is a highly conserved eukaryotic AAA + protein which is an essential cofactor for several complexes involved in chromatin acetylation and remodeling, transcriptional and developmental regulation and nucleolar organization and trafficking. We show that TIP48 abundance in HeLa cells did not change during the cell cycle, nor did its distribution in various biochemical fractions. However, we observed distinct changes in the subcellular localization of TIP48 during M phase using immunofluorescence microscopy. Our studies demonstrate that in interphase cells TIP48 was found mainly in the nucleus and exhibited a distinct localization in the nuclear periphery. As the cells entered mitosis, TIP48 was excluded from the condensing chromosomes but showed association with the mitotic apparatus. During anaphase, some TIP48 was detected in the centrosome colocalizing with tubulin but the strongest staining appeared in the mitotic equator associated with the midzone central spindle. Accumulation of TIP48 in the midzone and the midbody was observed in late telophase and cytokinesis. This redeployment of TIP48 during anaphase and cytokinesis was independent of microtubule assembly. The relocation of endogenous TIP48 to the midzone/midbody under physiological conditions suggests a novel and distinct function for TIP48 in mitosis and possible involvement in the exit of mitosis

  18. ASDF: A New Adaptable Data Format for Seismology Suitable for Large-Scale Workflows

    Science.gov (United States)

    Krischer, L.; Smith, J. A.; Spinuso, A.; Tromp, J.

    2014-12-01

    Increases in the amounts of available data as well as computational power opens the possibility to tackle ever larger and more complex problems. This comes with a slew of new problems, two of which are the need for a more efficient use of available resources and a sensible organization and storage of the data. Both need to be satisfied in order to properly scale a problem and both are frequent bottlenecks in large seismic inversions using ambient noise or more traditional techniques.We present recent developments and ideas regarding a new data format, named ASDF (Adaptable Seismic Data Format), for all branches of seismology aiding with the aforementioned problems. The key idea is to store all information necessary to fully understand a set of data in a single file. This enables the construction of self-explaining and exchangeable data sets facilitating collaboration on large-scale problems. We incorporate the existing metadata standards FDSN StationXML and QuakeML together with waveform and auxiliary data into a common container based on the HDF5 standard. A further critical component of the format is the storage of provenance information as an extension of W3C PROV, meaning information about the history of the data, assisting with the general problem of reproducibility.Applications of the proposed new format are numerous. In the context of seismic tomography it enables the full description and storage of synthetic waveforms including information about the used model, the solver, the parameters, and other variables that influenced the final waveforms. Furthermore, intermediate products like adjoint sources, cross correlations, and receiver functions can be described and most importantly exchanged with others.Usability and tool support is crucial for any new format to gain acceptance and we additionally present a fully functional implementation of this format based on Python and ObsPy. It offers a convenient way to discover and analyze data sets as well as making

  19. Applications of seismic spatial wavefield gradient and rotation data in exploration seismology

    Science.gov (United States)

    Schmelzbach, C.; Van Renterghem, C.; Sollberger, D.; Häusler, M.; Robertsson, J. O. A.

    2017-12-01

    Seismic spatial wavefield gradient and rotation data have the potential to open up new ways to address long-standing problems in land-seismic exploration such as identifying and separating P-, S-, and surface waves. Gradient-based acquisition and processing techniques could enable replacing large arrays of densely spaced receivers by sparse spatially-compact receiver layouts or even one single multicomponent station with dedicated instruments (e.g., rotational seismometers). Such approaches to maximize the information content of single-station recordings are also of significant interest for seismic measurements at sites with limited access such as boreholes, the sea bottom, and extraterrestrial seismology. Arrays of conventional three-component (3C) geophones enable measuring not only the particle velocity in three dimensions but also estimating their spatial gradients. Because the free-surface condition allows to express vertical derivatives in terms of horizontal derivatives, the full gradient tensor and, hence, curl and divergence of the wavefield can be computed. In total, three particle velocity components, three rotational components, and divergence, result seven-component (7C) seismic data. Combined particle velocity and gradient data can be used to isolate the incident P- or S-waves at the land surface or the sea bottom using filtering techniques based on the elastodynamic representation theorem. Alternatively, as only S-waves exhibit rotational motion, rotational measurements can directly be used to identify S-waves. We discuss the derivations of the gradient-based filters as well as their application to synthetic and field data, demonstrating that rotational data can be of particular interest to S-wave reflection and P-to-S-wave conversion imaging. The concept of array-derived gradient estimation can be extended to source arrays as well. Therefore, source arrays allow us to emulate rotational (curl) and dilatational (divergence) sources. Combined with 7C

  20. Engaging High School Science Teachers in Field-Based Seismology Research: Opportunities and Challenges

    Science.gov (United States)

    Long, M. D.

    2015-12-01

    Research experiences for secondary school science teachers have been shown to improve their students' test scores, and there is a substantial body of literature about the effectiveness of RET (Research Experience for Teachers) or SWEPT (Scientific Work Experience Programs for Teachers) programs. RET programs enjoy substantial support, and several opportunities for science teachers to engage in research currently exist. However, there are barriers to teacher participation in research projects; for example, laboratory-based projects can be time consuming and require extensive training before a participant can meaningfully engage in scientific inquiry. Field-based projects can be an effective avenue for involving teachers in research; at its best, earth science field work is a fun, highly immersive experience that meaningfully contributes to scientific research projects, and can provide a payoff that is out of proportion to a relatively small time commitment. In particular, broadband seismology deployments provide an excellent opportunity to provide teachers with field-based research experience. Such deployments are labor-intensive and require large teams, with field tasks that vary from digging holes and pouring concrete to constructing and configuring electronics systems and leveling and orienting seismometers. A recently established pilot program, known as FEST (Field Experiences for Science Teachers) is experimenting with providing one week of summer field experience for high school earth science teachers in Connecticut. Here I report on results and challenges from the first year of the program, which is funded by the NSF-CAREER program and is being run in conjunction with a temporary deployment of 15 seismometers in Connecticut, known as SEISConn (Seismic Experiment for Imaging Structure beneath Connecticut). A small group of teachers participated in a week of field work in August 2015 to deploy seismometers in northern CT; this experience followed a visit of the