Tornado-like transport in a magnetized plasma

Science.gov (United States)

Poulos, Matthew; van Compernolle, Bart; Morales, George

2017-10-01

Recent heat transport experiments conducted in the LAPD device at UCLA in which avalanche events have been previously documented have also lead to the identification of a new tornado-like transport phenomenon. These tornados occur much earlier than the avalanches events, essentially in the interval following the application of the bias voltage that causes the injection of an electron beam from a ring-shaped LaB6 cathode into the afterglow of a cold, magnetized plasma. The tornados exhibit a low-frequency (4 kHz) (much lower than drift-waves), spiraling, global eigenmode whose transient behavior is responsible for significant radial transport well outside the heated region. Detailed experimental observations are compared with a Braginskii transport code that includes the effects of ExB convection induced by the spiraling global eigenmode. New insights are gained into the necessary modifications of classical transport to accurately simulate the spiraling effects and the possible interaction with avalanches. This work is supported by the NSF/DOE partnership in basic plasma science and engineering, Grant Number 1619505, and is performed at the Basic Plasma Science Facility, sponsored jointly by DOE and NSF. Sponsored by DOE/NSF at BaPSF and NSF 1619505.

Generation of missiles by tornadoes

International Nuclear Information System (INIS)

1974-11-01

Available data on tornado wind velocities and wind distribution are incorporated into a mathematical model of the tornado wind field. The mathematical model is then used to predict the time-history of motion of a potential missile in a tornado wind field. (U.S.)

Pneumonia cases following an EF-5 tornado.

Science.gov (United States)

Forshee-Hakala, Beth A

2015-07-01

Infections following a natural disaster such as an EF-5 tornado can be atypical and difficult to treat. Studies have looked at illness following several natural disasters, but few have studied respiratory illness following a tornado. A review of patients with pneumonia admitted during the period from May 22, 2009, through May 21, 2012, was completed. The Tornado Zone Group included adult patients who lived or worked in the tornado zone during the year following the tornado. Data were isolated by number of pneumonia cases within and outside the tornado zone per month per year. An analysis of variance comparing the number of pneumonia cases from the tornado zone per month per year was significant at F2,38 = 12.93 and P Tornado Zone Group (P Tornado Zone patients to be younger than controls (t390 = 5.14; P Tornado Zone Group included uncommon pathogens not isolated during the 2 years prior. The number of pneumonia cases may increase following tornadoes. Although current guidelines recommend narrow-spectrum antibiotics for community-acquired pneumonia, results of this study suggest the possible need for broader antimicrobial coverage after tornadoes. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

What's Left After a Tornado.

Science.gov (United States)

Lawrence Inst. of Tech., Southfield, MI.

Following recent tornadoes, terms of specially trained architectural and engineering faculty conducted onsite examinations and research of building damage. It was concluded that tornado damage to buildings is predictable. A trained architect or engineer can establish, before a tornado strikes, those portions of the building that will offer the…

Climatological and regional characteristics of supercell tornado occurrence based on a long-term reanalysis of tornado parameters

International Nuclear Information System (INIS)

Sugimoto, Soichiro; Nohara, Daisuke; Hirakuchi, Hiromaru

2016-01-01

This study investigates tornado climatology in Japan in terms of the regionalization of tornado intensity. A 50-year reanalysis dataset (the horizontal resolution of 5 km and hourly interval), produced by downscaling using the WRF mesoscale model and ECMWF reanalysis datasets, is used to estimate tornado parameters such as convective available potential energy (CAPE) and 3-km storm relative helicity (SReH). Energy helicity index (EHI) is also calculated as a composite parameter. Based on a long-term reanalysis data of tornado parameters, the number of times simultaneously exceeding threshold values is counted for SReH and CAPE parameters. The same procedure is done for EHI parameter. The thresholds are set from meteorological analysis of F3 tornadoes that are currently the most intense in Japan. Results indicate that the Pacific side of Japan along the south coast is the most favorable region for the occurrence of the most intense scale of tornado. This is consistent with the fact that the paths of most of all F3 tornadoes are include in this high-frequency region in exceeding thresholds. In other hand, approximately one-order smaller frequency in exceeding than the Pacific sides is evaluated in the Japan Sea side, which suggests topographic effects of blocking humid unstable air mass transported from the Pacific Ocean. The tornado intensity region evaluated by our approach is useful for a probabilistic hazard analysis of tornado wind speeds in the implementation of impact assessment of tornadoes for nuclear power plants. (author)

Annihilation and Reanimation of a Tornado in the Improved Tornado Tube

Science.gov (United States)

Bednarek, Stanislaw

2016-01-01

Some new experiments using an improved version of the "tornado tube" are described here. The improved tornado tube consists of two plastic transparent bottles whose openings are connected with a ball valve, available at most hardware stores. After being filled with fluid and inverting, this tube allows demonstration of the generation,…

Genesis of tornadoes associated with hurricanes

Science.gov (United States)

Gentry, R. C.

1983-01-01

The climatological history of hurricane-tornadoes is brought up to date through 1982. Most of the tornadoes either form near the center of the hurricane, from the outer edge of the eyewall outward, or in an area between north and east-southeast of the hurricane center. The blackbody temperatures of the cloud tops which were analyzed for several hurricane-tornadoes that formed in the years 1974, 1975, and 1979, did not furnish strong precursor signals of tornado formation, but followed one of two patterns: either the temperatures were very low, or the tornado formed in areas of strong temperature gradients. Tornadoes with tropical cyclones most frequently occur at 1200-1800 LST, and although most are relatively weak, they can reach the F3 intensity level. Most form in association with the outer rainbands of the hurricane.

Assessing a Tornado Climatology from Global Tornado Intensity Distributions

OpenAIRE

Feuerstein, B.; Dotzek, N.; Grieser, J.

2005-01-01

Recent work demonstrated that the shape of tornado intensity distributions from various regions worldwide is well described by Weibull functions. This statistical modeling revealed a strong correlation between the fit parameters c for shape and b for scale regardless of the data source. In the present work it is shown that the quality of the Weibull fits is optimized if only tornado reports of F1 and higher intensity are used and that the c–b correlation does indeed reflect a universal featur...

Numerical Simulation of a Tornado Generating Supercell

Science.gov (United States)

Proctor, Fred H.; Ahmad, Nashat N.; LimonDuparcmeur, Fanny M.

2012-01-01

The development of tornadoes from a tornado generating supercell is investigated with a large eddy simulation weather model. Numerical simulations are initialized with a sounding representing the environment of a tornado producing supercell that affected North Carolina and Virginia during the Spring of 2011. The structure of the simulated storm was very similar to that of a classic supercell, and compared favorably to the storm that affected the vicinity of Raleigh, North Carolina. The presence of mid-level moisture was found to be important in determining whether a supercell would generate tornadoes. The simulations generated multiple tornadoes, including cyclonic-anticyclonic pairs. The structure and the evolution of these tornadoes are examined during their lifecycle.

The tornado risk in eastern Canada

International Nuclear Information System (INIS)

Asmis, G.J.K.

1980-01-01

In the United States, a tornado design requirement was imposed on nuclear power plants in 1967. This requirement precipitated considerable study on the probability of toronado strikes and the consequent damage. As a data base, records of thousands of tornadoes which occurred in the U.S. in the last 50 years were available. Unfortunately, no such data base exists for tornadoes and other extreme atmospheric events in Canada. A theoretical study employing a Monte Carlo technique was used to simulate the tornado environment for a hypothetical site. This exercise concluded that a site the size of a large nuclear park such as Bruce can be traversed by a tornado every 500 years. The results are very preliminary since very little Canadian data or meteorological considerations have been involved. The results do, however, show that the frequency of a tornado strike is in the order of 10 -3 events/annum and is therefore of concern in the safety assessment of nuclear facilities. (auth)

Tornado protection by venting

International Nuclear Information System (INIS)

Cavanagh, C.A.

1987-01-01

The purpose of this paper is to demonstrate the ability to protect a modern nuclear power plant from the effects of a tornado by the use of a system of venting in all safety-related structures outside of the containment. The paper demonstrates this by presenting a method of analysis and of equipment selection that fully complies with the intent and the letter of applicable federal regulatory guides. A report of an actual tornado in the City of Kalamazoo, Michigan, suggests that the concept of sealing a plant during a tornado may not always be applicable

Mexico tornado climatology

Directory of Open Access Journals (Sweden)

Manuel Macías Medrano

2013-07-01

Full Text Available A brief introduction on some features of tornado database in Mexico is exposed showing its substantive criteria. We resent a brief analysis about main Mexican tornadoes´ characteristics, based on data collected between 2000 to 2010, talking about spatial and temporal expressions (historical, seasonal and horary in order to show the importance of it destruction capacity and also the people´s vulnerability in Mexico.

Kinetic Energy of Tornadoes in the United States.

Directory of Open Access Journals (Sweden)

Tyler Fricker

Full Text Available Tornadoes can cause catastrophic destruction. Here total kinetic energy (TKE as a metric of destruction is computed from the fraction of the tornado path experiencing various damage levels and a characteristic wind speed for each level. The fraction of the path is obtained from a model developed for the Nuclear Regulatory Commission that combines theory with empirical data. TKE is validated as a useful metric by comparing it to other indexes and loss indicators. Half of all tornadoes have TKE exceeding 62.1 GJ and a quarter have TKE exceeding 383.2 GJ. One percent of the tornadoes have TKE exceeding 31.9 TJ. April has more energy than May with fewer tornadoes; March has more energy than June with half as many tornadoes. September has the least energy but November and December have the fewest tornadoes. Alabama ranks number one in terms of tornado energy with 2.48 PJ over the period 2007-2013. TKE can be used to help better understand the changing nature of tornado activity.

Kinetic Energy of Tornadoes in the United States.

Science.gov (United States)

Fricker, Tyler; Elsner, James B

2015-01-01

Tornadoes can cause catastrophic destruction. Here total kinetic energy (TKE) as a metric of destruction is computed from the fraction of the tornado path experiencing various damage levels and a characteristic wind speed for each level. The fraction of the path is obtained from a model developed for the Nuclear Regulatory Commission that combines theory with empirical data. TKE is validated as a useful metric by comparing it to other indexes and loss indicators. Half of all tornadoes have TKE exceeding 62.1 GJ and a quarter have TKE exceeding 383.2 GJ. One percent of the tornadoes have TKE exceeding 31.9 TJ. April has more energy than May with fewer tornadoes; March has more energy than June with half as many tornadoes. September has the least energy but November and December have the fewest tornadoes. Alabama ranks number one in terms of tornado energy with 2.48 PJ over the period 2007-2013. TKE can be used to help better understand the changing nature of tornado activity.

Characteristics of tornado generated missiles

International Nuclear Information System (INIS)

Bhattacharyya, A.K.; Boritz, R.C.; Niyogi, P.K.

1975-10-01

The development of techniques designed to calculate tornado missile velocities is traced. It is shown that there is a need for a consistent method for obtaining missile velocities for a variety of tornado parameters. A consistent method for determination of trajectories and velocities of missiles generated by a tornado is described. The effects of plant layout upon missile impact velocity at a given building are discussed from the point of view of determining the necessary missile barrier characteristics. 19 references

Apparent Solar Tornado-Like Prominences

Science.gov (United States)

Panasenco, Olga; Martin, Sara F.; Velli, Marco

2014-02-01

Recent high-resolution observations from the Solar Dynamics Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado-like prominences. This class of prominences was first introduced by Pettit ( Astrophys. J. 76, 9, 1932), who studied them over many years. Observations of tornado prominences similar to the ones seen by SDO had already been documented by Secchi ( Le Soleil, 1877). High-resolution and high-cadence multiwavelength data obtained by SDO reveal that the tornado-like appearance of these prominences is mainly an illusion due to projection effects. We discuss two different cases where prominences on the limb might appear to have a tornado-like behavior. One case of apparent vortical motions in prominence spines and barbs arises from the (mostly) 2D counterstreaming plasma motion along the prominence spine and barbs together with oscillations along individual threads. The other case of apparent rotational motion is observed in a prominence cavity and results from the 3D plasma motion along the writhed magnetic fields inside and along the prominence cavity as seen projected on the limb. Thus, the "tornado" impression results either from counterstreaming and oscillations or from the projection on the plane of the sky of plasma motion along magnetic-field lines, rather than from a true vortical motion around an (apparent) vertical or horizontal axis. We discuss the link between tornado-like prominences, filament barbs, and photospheric vortices at their base.

A Statistical Model for Regional Tornado Climate Studies.

Science.gov (United States)

Jagger, Thomas H; Elsner, James B; Widen, Holly M

2015-01-01

Tornado reports are locally rare, often clustered, and of variable quality making it difficult to use them directly to describe regional tornado climatology. Here a statistical model is demonstrated that overcomes some of these difficulties and produces a smoothed regional-scale climatology of tornado occurrences. The model is applied to data aggregated at the level of counties. These data include annual population, annual tornado counts and an index of terrain roughness. The model has a term to capture the smoothed frequency relative to the state average. The model is used to examine whether terrain roughness is related to tornado frequency and whether there are differences in tornado activity by County Warning Area (CWA). A key finding is that tornado reports increase by 13% for a two-fold increase in population across Kansas after accounting for improvements in rating procedures. Independent of this relationship, tornadoes have been increasing at an annual rate of 1.9%. Another finding is the pattern of correlated residuals showing more Kansas tornadoes in a corridor of counties running roughly north to south across the west central part of the state consistent with the dryline climatology. The model is significantly improved by adding terrain roughness. The effect amounts to an 18% reduction in the number of tornadoes for every ten meter increase in elevation standard deviation. The model indicates that tornadoes are 51% more likely to occur in counties served by the CWAs of DDC and GID than elsewhere in the state. Flexibility of the model is illustrated by fitting it to data from Illinois, Mississippi, South Dakota, and Ohio.

Mathematical modeling of tornadoes and squall storms

Directory of Open Access Journals (Sweden)

Sergey A. Arsen’yev

2011-04-01

Full Text Available Recent advances in modeling of tornadoes and twisters consist of significant achievements in mathematical calculation of occurrence and evolution of a violent F5-class tornado on the Fujita scale, and four-dimensional mathematical modeling of a tornado with the fourth coordinate time multiplied by its characteristic velocity. Such a tornado can arise in a thunderstorm supercell filled with turbulent whirlwinds. A theory of the squall storms is proposed. The squall storm is modeled by running perturbation of the temperature inversion on the lower boundary of cloudiness. This perturbation is induced by the action of strong, hurricane winds in the upper and middle troposphere, and looks like a running solitary wave (soliton; which is developed also in a field of pressure and velocity of a wind. If a soliton of a squall storm gets into the thunderstorm supercell then this soliton is captured by supercell. It leads to additional pressure fall of air inside a storm supercell and stimulate amplification of wind velocity here. As a result, a cyclostrophic balance inside a storm supercell generates a tornado. Comparison of the radial distribution of wind velocity inside a tornado calculated by using the new formulas and equations with radar observations of the wind velocity inside Texas Tornado Dummit in 1995 and inside the 3 May 1999 Oklahoma City Tornado shows good correspondence.

A Statistical Model for Regional Tornado Climate Studies.

Directory of Open Access Journals (Sweden)

Thomas H Jagger

Full Text Available Tornado reports are locally rare, often clustered, and of variable quality making it difficult to use them directly to describe regional tornado climatology. Here a statistical model is demonstrated that overcomes some of these difficulties and produces a smoothed regional-scale climatology of tornado occurrences. The model is applied to data aggregated at the level of counties. These data include annual population, annual tornado counts and an index of terrain roughness. The model has a term to capture the smoothed frequency relative to the state average. The model is used to examine whether terrain roughness is related to tornado frequency and whether there are differences in tornado activity by County Warning Area (CWA. A key finding is that tornado reports increase by 13% for a two-fold increase in population across Kansas after accounting for improvements in rating procedures. Independent of this relationship, tornadoes have been increasing at an annual rate of 1.9%. Another finding is the pattern of correlated residuals showing more Kansas tornadoes in a corridor of counties running roughly north to south across the west central part of the state consistent with the dryline climatology. The model is significantly improved by adding terrain roughness. The effect amounts to an 18% reduction in the number of tornadoes for every ten meter increase in elevation standard deviation. The model indicates that tornadoes are 51% more likely to occur in counties served by the CWAs of DDC and GID than elsewhere in the state. Flexibility of the model is illustrated by fitting it to data from Illinois, Mississippi, South Dakota, and Ohio.

Three scales of motions associated with tornadoes

International Nuclear Information System (INIS)

Forbes, G.S.

1978-03-01

This dissertation explores three scales of motion commonly associated with tornadoes, and the interaction of these scales: the tornado cyclone, the tornado, and the suction vortex. The goal of the research is to specify in detail the character and interaction of these scales of motion to explain tornadic phenomena

Solar Magnetized Tornadoes: Rotational Motion in a Tornado-like Prominence

Science.gov (United States)

Su, Yang; Gömöry, Peter; Veronig, Astrid; Temmer, Manuela; Wang, Tongjiang; Vanninathan, Kamalam; Gan, Weiqun; Li, YouPing

2014-04-01

Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ~5 km s-1.

SOLAR MAGNETIZED 'TORNADOES': RELATION TO FILAMENTS

Energy Technology Data Exchange (ETDEWEB)

Su Yang; Veronig, Astrid; Temmer, Manuela [IGAM-Kanzelhoehe Observatory, Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria); Wang Tongjiang [Department of Physics, Catholic University of America, Washington, DC 20064 (United States); Gan Weiqun, E-mail: yang.su@uni-graz.at [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2012-09-10

Solar magnetized 'tornadoes', a phenomenon discovered in the solar atmosphere, appear as tornado-like structures in the corona but are rooted in the photosphere. Like other solar phenomena, solar tornadoes are a feature of magnetized plasma and therefore differ distinctly from terrestrial tornadoes. Here we report the first analysis of solar 'tornadoes' (two papers which focused on different aspects of solar tornadoes were published in the Astrophysical Journal Letters and Nature, respectively, during the revision of this Letter). A detailed case study of two events indicates that they are rotating vertical magnetic structures probably driven by underlying vortex flows in the photosphere. They usually exist as a group and are related to filaments/prominences, another important solar phenomenon whose formation and eruption are still mysteries. Solar tornadoes may play a distinct role in the supply of mass and twists to filaments. These findings could lead to a new explanation of filament formation and eruption.

Changing volatility of U.S. annual tornado reports

Science.gov (United States)

Tippett, Michael K.

2014-10-01

United States (U.S.) tornado activity results in substantial loss of life and property damage each year. A simple measure of the U.S. tornado climatology is the average number of tornadoes per year. However, even this statistic is elusive because of nonstationary behavior due in large part to changes in reporting practices. Differencing of the annual report data results in a quantity without mean trends and whose standard deviation we denote as volatility, since it is an indication of the likely year-to-year variation in the number of tornadoes reported. While volatility changes detected prior to 2000 can be associated with known reporting practice changes, an increase in volatility in the 2000s across intensity levels cannot. A volatility increase is also seen in a tornado environment index which measures the favorability of atmospheric conditions to tornado activity, providing evidence that the recent increase in tornado report volatility is related to the physical environment.

Dispersion of small particles in a tornado

International Nuclear Information System (INIS)

Pepper, D.W.

1975-05-01

Based on 22 years of tornado statistics for South Carolina and Georgia, the probability of a tornado of Class F3 or greater striking a point at the Savannah River Plant is calculated to be approximately 14 x 10 -5 per year. These statistics show that Class F3 tornados (0.56-psi pressure drop and winds of 158 to 206 mph), are the most frequently occurring but cause only 23 percent of the damage compared with all classes of tornadoes. F4 tornadoes (1.10-psi pressure drop and winds of 207 to 260 mph) constitute only 20 percent of the total, but cause 63 percent of the damage. A Gaussian diffusion model is used to calculate the ground level concentration (ratio of concentration to source mass chi/Q) as a function of distance downwind should a tornado strike a point within the Savannah River Plant (SRP). The particles released to the atmosphere are assumed to be 1 to 3-μm diameter. For the calculations, two cases of possible small particle pickup are considered. In Case I a unit source of small particles is assumed to be injected into the tornado core and transported into the thunderstorm. In Case II, the cluster of particles is assumed to exit the side of the tornado core below the thunderstorm cloud. Several different stabilization heights within the thunderstorm, different horizontal wind speeds, and different turbulence dissipation rates are assumed for the calculations. (U.S.)

ARE GIANT TORNADOES THE LEGS OF SOLAR PROMINENCES?

Energy Technology Data Exchange (ETDEWEB)

Wedemeyer, Sven; Scullion, Eamon; Rouppe van der Voort, Luc; Bosnjak, Antonija [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Antolin, Patrick, E-mail: sven.wedemeyer@astro.uio.no [Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, bus 2400, B-3001 Leuven (Belgium)

2013-09-10

Observations in the 171 A channel of the Atmospheric Imaging Assembly of the space-borne Solar Dynamics Observatory show tornado-like features in the atmosphere of the Sun. These giant tornadoes appear as dark, elongated, and apparently rotating structures in front of a brighter background. This phenomenon is thought to be produced by rotating magnetic field structures that extend throughout the atmosphere. We characterize giant tornadoes through a statistical analysis of properties such as spatial distribution, lifetimes, and sizes. A total number of 201 giant tornadoes are detected in a period of 25 days, suggesting that, on average, about 30 events are present across the whole Sun at a time close to solar maximum. Most tornadoes appear in groups and seem to form the legs of prominences, thus serving as plasma sources/sinks. Additional H{alpha} observations with the Swedish 1 m Solar Telescope imply that giant tornadoes rotate as a structure, although they clearly exhibit a thread-like structure. We observe tornado groups that grow prior to the eruption of the connected prominence. The rotation of the tornadoes may progressively twist the magnetic structure of the prominence until it becomes unstable and erupts. Finally, we investigate the potential relation of giant tornadoes to other phenomena, which may also be produced by rotating magnetic field structures. A comparison to cyclones, magnetic tornadoes, and spicules implies that such events are more abundant and short-lived the smaller they are. This comparison might help to construct a power law for the effective atmospheric heating contribution as a function of spatial scale.

ARE GIANT TORNADOES THE LEGS OF SOLAR PROMINENCES?

International Nuclear Information System (INIS)

Wedemeyer, Sven; Scullion, Eamon; Rouppe van der Voort, Luc; Bosnjak, Antonija; Antolin, Patrick

2013-01-01

Observations in the 171 Å channel of the Atmospheric Imaging Assembly of the space-borne Solar Dynamics Observatory show tornado-like features in the atmosphere of the Sun. These giant tornadoes appear as dark, elongated, and apparently rotating structures in front of a brighter background. This phenomenon is thought to be produced by rotating magnetic field structures that extend throughout the atmosphere. We characterize giant tornadoes through a statistical analysis of properties such as spatial distribution, lifetimes, and sizes. A total number of 201 giant tornadoes are detected in a period of 25 days, suggesting that, on average, about 30 events are present across the whole Sun at a time close to solar maximum. Most tornadoes appear in groups and seem to form the legs of prominences, thus serving as plasma sources/sinks. Additional Hα observations with the Swedish 1 m Solar Telescope imply that giant tornadoes rotate as a structure, although they clearly exhibit a thread-like structure. We observe tornado groups that grow prior to the eruption of the connected prominence. The rotation of the tornadoes may progressively twist the magnetic structure of the prominence until it becomes unstable and erupts. Finally, we investigate the potential relation of giant tornadoes to other phenomena, which may also be produced by rotating magnetic field structures. A comparison to cyclones, magnetic tornadoes, and spicules implies that such events are more abundant and short-lived the smaller they are. This comparison might help to construct a power law for the effective atmospheric heating contribution as a function of spatial scale

Methods for tornado frequency calculation of nuclear power plant

International Nuclear Information System (INIS)

Liu Haibin; Li Lin

2012-01-01

In order to take probabilistic safety assessment of nuclear power plant tornado attack event, a method to calculate tornado frequency of nuclear power plant is introduced based on HAD 101/10 and NUREG/CR-4839 references. This method can consider history tornado frequency of the plant area, construction dimension, intensity various along with tornado path and area distribution and so on and calculate the frequency of different scale tornado. (authors)

Increased variability of tornado occurrence in the United States.

Science.gov (United States)

Brooks, Harold E; Carbin, Gregory W; Marsh, Patrick T

2014-10-17

Whether or not climate change has had an impact on the occurrence of tornadoes in the United States has become a question of high public and scientific interest, but changes in how tornadoes are reported have made it difficult to answer it convincingly. We show that, excluding the weakest tornadoes, the mean annual number of tornadoes has remained relatively constant, but their variability of occurrence has increased since the 1970s. This is due to a decrease in the number of days per year with tornadoes combined with an increase in days with many tornadoes, leading to greater variability on annual and monthly time scales and changes in the timing of the start of the tornado season. Copyright © 2014, American Association for the Advancement of Science.

Risk factors for tornado injuries.

Science.gov (United States)

Eidson, M; Lybarger, J A; Parsons, J E; MacCormack, J N; Freeman, J I

1990-12-01

Tornadoes in North and South Carolina on 28 March 1984 caused 252 people to be injured seriously enough to require hospitalization and 59 to be killed. To evaluate risk factors, we gathered information on 238 (94%) of those hospitalized and 46 (78%) of those killed. Those hospitalized or deceased had statistically significantly more deep cuts, concussions, unconsciousness and broken bones than those with them at the time of the tornado who were not hospitalized or killed. People living in mobile homes were more likely to be hospitalized or die than people occupying conventional houses. Other risk factors for hospitalization or death included advanced age (60+ years), no physical protection (not having been covered with a blanket or other object), having been struck by broken window glass or other falling objects, home lifted off its foundation, collapsed ceiling or floor, or walls blown away. More awareness of the tornado risk before it strikes and better adherence to tornado protection guidelines could reduce injuries and deaths in the future.

Tornado Strikes Southern Maryland

Science.gov (United States)

2002-01-01

Evening light catches the tops of towering thunderheads over the Mid-Atlantic states on April 28, 2002. The powerful storms spawned several tornados, one of which was classified as an F4 tornado. The powerful tornado touched down in the southern Maryland town of La Plata, destroying most of the historic downtown. The twister-one of the strongest ever to hit the state-beat a 24-mile swath running west to east through the state and claimed at least three lives. The image above was taken by the Geostationary Operational Environmental Satellite (GOES) at 7:15 PM Eastern Daylight Savings Time. A large version of the animation shows more detail. (5.9 MB Quicktime) Image courtesy National Oceanic and Atmospheric Administration (NOAA) and the GOES Project Science Office. Animation by Robert Simmon, NASA GSFC.

Self-organization in the tornado: the new approach in the tornado description

OpenAIRE

Bystrai, G. P.; Lykov, I. A

2012-01-01

For the mathematical modeling of highly non-equilibrium and nonlinear processes in a tornado in this paper a new approach based on nonlinear equations of momentum transfer with function of sources and sinks is suggested. In constructing the model thermodynamic description is used, which is not entered before and allows discovering new principles of self-organization in a tornado. This approach gives fairly consistent physical results. This is an attempt to answer some fundamental questions co...

Wind and tornado guidelines

International Nuclear Information System (INIS)

McDonald, J.R.

1989-01-01

The objective of the Department of Energy Natural Phenomena Hazards Project is to provide guidance and criteria for design of new facilities and for evaluation of existing ones subjected to extreme winds, earthquakes, and floods. This paper describes the treatment of wind and tornado hazards. Four facility-use categories are defined which represent increasing levels of risk to personnel or the environment in the event of a high wind event. Facilities are assigned to a particular category, depending on their mission, value, or toxic material content. The assigned facility-use category determines the design and evaluation criteria. The criteria are based on probabilistic hazard assessment. Performance goals are also specified for each facility-use category. A uniform approach to design wind loads, based on the ANSI A58.1-1982 standard, allows treatment of high winds and hurricane and tornado winds in a similar manner. Based on the wind hazard models, some sites must account for the possibility of tornadoes while others do not. Atmospheric pressure changes and missiles must be taken into account when considering tornadoes. The design and evaluation guidelines are designed to establish consistent levels of risk for different natural phenomena hazards and for facilities at different geographical locations

Tornado-borne missile speeds. Final report

International Nuclear Information System (INIS)

Simiu, E.; Cordes, M.

1976-04-01

An investigation of the question of tornado-borne missile speeds was carried out, with a view to identify pertinent areas of uncertainty and to estimate credible tornado-borne missile speeds - within the limitations inherent in the present state of the art. The investigation consists of two parts: (1) a study in which a rational model for the missile motion is proposed, and numerical experiments are carried out corresponding to various assumptions on the initial conditions of the missile motion, the structure of the tornado flow, and the aerodynamic properties of the missile; (2) a theoretical and experimental study of tornado-borne missile aerodynamics, conducted by Colorado State Univ. (CSU) to be covered in a separate report by CSU. In the present report, the factors affecting missile motion and their influence upon such motion are examined

SOLAR MAGNETIZED TORNADOES: ROTATIONAL MOTION IN A TORNADO-LIKE PROMINENCE

Energy Technology Data Exchange (ETDEWEB)

Su, Yang; Veronig, Astrid; Temmer, Manuela; Vanninathan, Kamalam [IGAM-Kanzelhöhe Observatory, Institute of Physics, University of Graz, Universitätsplatz 5, A-8010 Graz (Austria); Gömöry, Peter [Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranská Lomnica (Slovakia); Wang, Tongjiang [Department of Physics, the Catholic University of America, Washington, DC 20064 (United States); Gan, Weiqun; Li, YouPing, E-mail: yang.su@uni-graz.at [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2014-04-10

Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ∼5 km s{sup –1}.

SOLAR MAGNETIZED TORNADOES: ROTATIONAL MOTION IN A TORNADO-LIKE PROMINENCE

International Nuclear Information System (INIS)

Su, Yang; Veronig, Astrid; Temmer, Manuela; Vanninathan, Kamalam; Gömöry, Peter; Wang, Tongjiang; Gan, Weiqun; Li, YouPing

2014-01-01

Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ∼5 km s –1

Some New Ideas About Tornadoes

Science.gov (United States)

Weigel, Edwin P.

1975-01-01

Based on the assumption that if occupants of buildings knew which places in these buildings were relatively safe in disasters such as tornadoes, and if they had sufficient warning, architects and engineers feel there is a significant opportunity to advance the art of school (or building) design to provide tornado-protected areas. (EB)

Modeling the Excitation of Seismic Waves by the Joplin Tornado

Science.gov (United States)

Valovcin, Anne; Tanimoto, Toshiro

2017-10-01

Tornadoes generate seismic signals when they contact the ground. Here we examine the signals excited by the Joplin tornado, which passed within 2 km of a station in the Earthscope Transportable Array. We model the tornado-generated vertical seismic signal at low frequencies (0.01-0.03 Hz) and solve for the strength of the seismic source. The resulting source amplitude is largest when the tornado was reported to be strongest (EF 4-5), and the amplitude is smallest when the tornado was weak (EF 0-2). A further understanding of the relationship between source amplitude and tornado intensity could open up new ways to study tornadoes from the ground.

Population and energy elasticity of tornado casualties

Science.gov (United States)

Fricker, Tyler; Elsner, James B.; Jagger, Thomas H.

2017-04-01

Tornadoes are capable of catastrophic destruction and mass casualties, but there are yet no estimates of how sensitive the number of casualties are to changes in the number of people in harm's way or to changes in tornado energy. Here the relationship between tornado casualties (deaths and injuries), population, and energy dissipation is quantified using the economic concept of "elasticity." Records of casualties from individual tornadoes over the period 2007-2015 are fit to a regression model. The coefficient on the population term (population elasticity) indicates that a doubling in population increases the casualty rate by 21% [(17, 24)%, 95% credible interval]. The coefficient on the energy term (energy elasticity) indicates that a doubling in energy dissipation leads to a 33% [(30, 35)%, 95% credible interval] increase in the casualty rate. The difference in elasticity values show that on average, changes in energy dissipation have been relatively more important in explaining tornado casualties than changes in population. Assuming no changes in warning effectiveness or mitigation efforts, these elasticity estimates can be used to project changes in casualties given the known population trends and possible trends in tornado activity.

The probability of a tornado missile hitting a target

International Nuclear Information System (INIS)

Goodman, J.; Koch, J.E.

1983-01-01

It is shown that tornado missile transportation is a diffusion Markovian process. Therefore, the Green's function method is applied for the estimation of the probability of hitting a unit target area. This propability is expressed through a joint density of tornado intensity and path area, a probability of tornado missile injection and a tornado missile height distribution. (orig.)

Infrasonic Emissions From A Tornado

Science.gov (United States)

Petrin, Christopher; Elbing, Brian

2017-11-01

Tornadoes cause dozens of deaths and significant damage throughout the United States every year. Tornado-producing storm systems emit infrasound (sound at frequencies below human hearing) up to 2 hours before tornadogenesis. Weak atmospheric attenuation at these frequencies allows them to be detected hundreds of miles away. Hence, passive infrasonic monitoring may be used for long-range study of tornadogenesis. This requires characterization of infrasound during the life of a tornado and from other background sources. This is being accomplished as part of the Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics (CLOUD-MAP) project, a multi-university collaboration focused on the development and implementation of unmanned aerial systems (UAS) and their integration with sensors for atmospheric measurement. This presentation will report findings from a fixed infrasonic microphone that has been continuously monitoring the atmosphere since September 2, 2016. Infrasound from a tornado that occurred 19 km from the microphone on May 11, 2017 will be presented as well as an overview of other infrasonic observations. This work was supported by NSF Grant 1539070.

Vorticity budget of a tornado-like vortex

Energy Technology Data Exchange (ETDEWEB)

Sassa, Koji; Takemura, Saki, E-mail: sassa@kochi-u.ac.jp [Department of Applied Science, Kochi University (Japan)

2011-12-22

We evaluated the vorticity budget of a tornado-like vortex by measuring vertical and horizontal circulations of it. Though spiral horizontal vortices are clearly observed to converge and tilted into the tornado-like vortex, their circulation is quite small. The conversion of the vertical vorticity concentrated at the side of the spiral horizontal vortices was found to mainly contribute to the maintenance of the tornado-like vortex.

Impact assessment of tornado against nuclear power plant

International Nuclear Information System (INIS)

Sato, Daisuke

2015-01-01

The impact assessment of tornado against nuclear power plants conforms to the 'Assessment guide for tornado effect on nuclear power plants' stipulated by the Nuclear Regulation Authority. In face of the assessment, important items are the setting of the maximum wind speed considered in design, and the setting of a flying object evaluation model, on the basis of observation results. The Japan Society of Maintenology summarized the verification results of the concept on the setting of tornado design and flying object valuation model, the contents of which are explained here. The following are explained: (1) validity of the setting of tornado design in the Assessment Guide, (2) analysis of synoptic field, (3) study on the regional characteristics of tornado occurrence environmental field by means of the analysis of synoptic field and gust associated index, and (4) setting of tornado design based on the above (1)-(3). Next, on the flying object evaluation model, the authors picked up the Rankine vortex model and Fujita model, and verified the reproducibility of the models using the features of each and the actual state of tornado damage. (A.O.)

Impact of tornadoes on hospital admissions for acute cardiovascular events.

Science.gov (United States)

Silva-Palacios, Federico; Casanegra, Ana Isabel; Shapiro, Alan; Phan, Minh; Hawkins, Beau; Li, Ji; Stoner, Julie; Tafur, Alfonso

2015-11-01

There is a paucity of data describing cardiovascular events after tornado outbreaks. We proposed to study the effects of tornadoes on the incidence of cardiovascular events at a tertiary care institution. Hospital admission records from a single center situated in a tornado-prone area three months before and after a 2013 tornado outbreak were abstracted. To control for seasonal variation, we also abstracted data from the same period of the prior year (control). Hospital admissions for cardiovascular events (CVEs) including acute myocardial infarction, stroke and venous thromboembolism (VTE) were summated by zip codes, and compared by time period. There were 22,607 admissions analyzed, of which 6,705 (30%), 7,980 (35%), and 7,922 (35%) were during the pre-tornado, post-tornado, and control time frames, respectively. There were 344 CVE in the controls, 317 CVE in pre-tornado and 364 CVEs in post tornado periods. There was no difference in the prevalence of CVE during the post-tornado season compared with the control (PPR=1.05 95% CI: 0.91 to 1.21, p=0.50) or the pre-tornado season (PPR=0.96, 95% CI: 0.83 to 1.21, p=0.63). In conclusion, tornado outbreaks did not increase the prevalence of cardiovascular events. In contrast to the effect of hurricanes, implementation of a healthcare policy change directed toward the early treatment and prevention of cardiovascular events after tornadoes does not seem warranted. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rationale for reduced tornado design bases

International Nuclear Information System (INIS)

Rutherford, P.D.; Ho, H.W.; Hartung, J.A.; Kastenberg, W.E.

1985-01-01

This paper provides a rationale for relaxing the present NRC tornado design requirements, which are based on a design basis tornado (DBT) whose frequency of exceedance is 10 -7 per year. It is proposed that a reduced DBT frequency of 10 -5 to 10 -6 per year is acceptable. This change in the tornado design bases for LMFBRs (and possibly all types of nuclear plants) is justified based on (1) existing NRC regulations and guidelines, (2) probabilistic arguments, (3) consistency with NRC trial safety goals, and (4) cost-benefit analysis

Tornadoes Strike Northern Wisconsin

Science.gov (United States)

2007-01-01

A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

Magnetohydrodynamic Models of Molecular Tornadoes

Science.gov (United States)

Au, Kelvin; Fiege, Jason D.

2017-07-01

Recent observations near the Galactic Center (GC) have found several molecular filaments displaying striking helically wound morphology that are collectively known as molecular tornadoes. We investigate the equilibrium structure of these molecular tornadoes by formulating a magnetohydrodynamic model of a rotating, helically magnetized filament. A special analytical solution is derived where centrifugal forces balance exactly with toroidal magnetic stress. From the physics of torsional Alfvén waves we derive a constraint that links the toroidal flux-to-mass ratio and the pitch angle of the helical field to the rotation laws, which we find to be an important component in describing the molecular tornado structure. The models are compared to the Ostriker solution for isothermal, nonmagnetic, nonrotating filaments. We find that neither the analytic model nor the Alfvén wave model suffer from the unphysical density inversions noted by other authors. A Monte Carlo exploration of our parameter space is constrained by observational measurements of the Pigtail Molecular Cloud, the Double Helix Nebula, and the GC Molecular Tornado. Observable properties such as the velocity dispersion, filament radius, linear mass, and surface pressure can be used to derive three dimensionless constraints for our dimensionless models of these three objects. A virial analysis of these constrained models is studied for these three molecular tornadoes. We find that self-gravity is relatively unimportant, whereas magnetic fields and external pressure play a dominant role in the confinement and equilibrium radial structure of these objects.

Magnetohydrodynamic Models of Molecular Tornadoes

Energy Technology Data Exchange (ETDEWEB)

Au, Kelvin; Fiege, Jason D., E-mail: fiege@physics.umanitoba.ca [Department of Physics and Astronomy, University of Manitoba Winnipeg, MB R3T 2N2 (Canada)

2017-07-10

Recent observations near the Galactic Center (GC) have found several molecular filaments displaying striking helically wound morphology that are collectively known as molecular tornadoes. We investigate the equilibrium structure of these molecular tornadoes by formulating a magnetohydrodynamic model of a rotating, helically magnetized filament. A special analytical solution is derived where centrifugal forces balance exactly with toroidal magnetic stress. From the physics of torsional Alfvén waves we derive a constraint that links the toroidal flux-to-mass ratio and the pitch angle of the helical field to the rotation laws, which we find to be an important component in describing the molecular tornado structure. The models are compared to the Ostriker solution for isothermal, nonmagnetic, nonrotating filaments. We find that neither the analytic model nor the Alfvén wave model suffer from the unphysical density inversions noted by other authors. A Monte Carlo exploration of our parameter space is constrained by observational measurements of the Pigtail Molecular Cloud, the Double Helix Nebula, and the GC Molecular Tornado. Observable properties such as the velocity dispersion, filament radius, linear mass, and surface pressure can be used to derive three dimensionless constraints for our dimensionless models of these three objects. A virial analysis of these constrained models is studied for these three molecular tornadoes. We find that self-gravity is relatively unimportant, whereas magnetic fields and external pressure play a dominant role in the confinement and equilibrium radial structure of these objects.

Science 101: What Causes Severe Thunderstorms and Tornadoes?

Science.gov (United States)

Robertson, Bill

2016-01-01

What causes severe thunderstorms and tornadoes? Tornadoes, often accompanied by severe thunderstorms and hail, form in pretty much the same way as severe thunderstorms. In the continental United States, tornadoes usually form in spring and summer, when warm, humid air from the Gulf of Mexico moves across the continent from southeast to northwest…

Tornado intensity estimated from damage path dimensions.

Science.gov (United States)

Elsner, James B; Jagger, Thomas H; Elsner, Ian J

2014-01-01

The Newcastle/Moore and El Reno tornadoes of May 2013 are recent reminders of the destructive power of tornadoes. A direct estimate of a tornado's power is difficult and dangerous to get. An indirect estimate on a categorical scale is available from a post-storm survery of the damage. Wind speed bounds are attached to the scale, but the scale is not adequate for analyzing trends in tornado intensity separate from trends in tornado frequency. Here tornado intensity on a continuum is estimated from damage path length and width, which are measured on continuous scales and correlated to the EF rating. The wind speeds on the EF scale are treated as interval censored data and regressed onto the path dimensions and fatalities. The regression model indicates a 25% increase in expected intensity over a threshold intensity of 29 m s(-1) for a 100 km increase in path length and a 17% increase in expected intensity for a one km increase in path width. The model shows a 43% increase in the expected intensity when fatalities are observed controlling for path dimensions. The estimated wind speeds correlate at a level of .77 (.34, .93) [95% confidence interval] with a small sample of wind speeds estimated independently from a doppler radar calibration. The estimated wind speeds allow analyses to be done on the tornado database that are not possible with the categorical scale. The modeled intensities can be used in climatology and in environmental and engineering applications. Research is needed to understand the upward trends in path length and width.

Tornado intensity estimated from damage path dimensions.

Directory of Open Access Journals (Sweden)

James B Elsner

Full Text Available The Newcastle/Moore and El Reno tornadoes of May 2013 are recent reminders of the destructive power of tornadoes. A direct estimate of a tornado's power is difficult and dangerous to get. An indirect estimate on a categorical scale is available from a post-storm survery of the damage. Wind speed bounds are attached to the scale, but the scale is not adequate for analyzing trends in tornado intensity separate from trends in tornado frequency. Here tornado intensity on a continuum is estimated from damage path length and width, which are measured on continuous scales and correlated to the EF rating. The wind speeds on the EF scale are treated as interval censored data and regressed onto the path dimensions and fatalities. The regression model indicates a 25% increase in expected intensity over a threshold intensity of 29 m s(-1 for a 100 km increase in path length and a 17% increase in expected intensity for a one km increase in path width. The model shows a 43% increase in the expected intensity when fatalities are observed controlling for path dimensions. The estimated wind speeds correlate at a level of .77 (.34, .93 [95% confidence interval] with a small sample of wind speeds estimated independently from a doppler radar calibration. The estimated wind speeds allow analyses to be done on the tornado database that are not possible with the categorical scale. The modeled intensities can be used in climatology and in environmental and engineering applications. Research is needed to understand the upward trends in path length and width.

Dual-Polarimetric Radar-Based Tornado Debris Signatures and Paths Associated with Tornadoes Over Northern Alabama During the Historic Outbreak of 27 April 2011

Science.gov (United States)

Carey, Lawrence D.; Schultz, Christopher J.; Schultz, Elise V.; Petersen, Walter A.; Gatlin, Patrick N.; Knupp, Kevin R.; Molthan, Andrew L.; Jedloved, Gary J.; Carcione, Brian C.; Darden, Christopher B.;

Review of worldwide occurrence of tornadoes

CSIR Research Space (South Africa)

Goliger, Adam M

1998-01-01

Full Text Available of about 3]10~5/yr/km2. Tornado events were also reported in Holland, Spain, Switzerland and Malta. 6. Africa Tornado events have been recorded in several Southern African countries (Bot- swana, Swaziland and Namibia) and possibly over Liberia, Ivory Coast...

Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets

Energy Technology Data Exchange (ETDEWEB)

Chen, Huadong; Zhang, Jun; Ma, Suli [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Yan, Xiaoli [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Xue, Jianchao, E-mail: hdchen@nao.cas.cn, E-mail: zjun@nao.cas.cn [Key Laboratory for Dark Matter and Space Science, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2017-05-20

We investigate the formations and evolutions of two successive solar tornadoes in/near AR 12297 during 2015 March 19–20. Recurrent EUV jets close to two filaments were detected along a large-scale coronal loop prior to the appearances of the tornadoes. Under the disturbances from the activities, the filaments continually ascended and finally interacted with the loops tracked by the jets. Subsequently, the structures of the filaments and the loop were merged together, probably via magnetic reconnections, and formed tornado-like structures with a long spiral arm. Our observations suggest that solar tornadoes can be triggered by the interaction between filaments and nearby coronal jets, which has rarely been reported before. At the earlier development phase of the first tornado, about 30 small-scale sub-jets appeared in the tornado’s arm, accompanied by local EUV brightenings. They have an ejection direction approximately vertical to the axis of the arm and a typical maximum speed of ∼280 km s{sup −1}. During the ruinations of the two tornadoes, fast plasma outflows from the strong EUV brightenings inside tornadoes are observed, in company with the untangling or unwinding of the highly twisted tornado structures. These observational features indicate that self reconnections probably occurred between the tangled magnetic fields of the tornadoes and resulted in the rapid disintegrations and disappearances of the tornadoes. According to the reconnection theory, we also derive the field strength of the tornado core to be ∼8 G.

Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets

International Nuclear Information System (INIS)

Chen, Huadong; Zhang, Jun; Ma, Suli; Yan, Xiaoli; Xue, Jianchao

2017-01-01

We investigate the formations and evolutions of two successive solar tornadoes in/near AR 12297 during 2015 March 19–20. Recurrent EUV jets close to two filaments were detected along a large-scale coronal loop prior to the appearances of the tornadoes. Under the disturbances from the activities, the filaments continually ascended and finally interacted with the loops tracked by the jets. Subsequently, the structures of the filaments and the loop were merged together, probably via magnetic reconnections, and formed tornado-like structures with a long spiral arm. Our observations suggest that solar tornadoes can be triggered by the interaction between filaments and nearby coronal jets, which has rarely been reported before. At the earlier development phase of the first tornado, about 30 small-scale sub-jets appeared in the tornado’s arm, accompanied by local EUV brightenings. They have an ejection direction approximately vertical to the axis of the arm and a typical maximum speed of ∼280 km s −1 . During the ruinations of the two tornadoes, fast plasma outflows from the strong EUV brightenings inside tornadoes are observed, in company with the untangling or unwinding of the highly twisted tornado structures. These observational features indicate that self reconnections probably occurred between the tangled magnetic fields of the tornadoes and resulted in the rapid disintegrations and disappearances of the tornadoes. According to the reconnection theory, we also derive the field strength of the tornado core to be ∼8 G.

Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets

Science.gov (United States)

Chen, Huadong; Zhang, Jun; Ma, Suli; Yan, Xiaoli; Xue, Jianchao

2017-05-01

We investigate the formations and evolutions of two successive solar tornadoes in/near AR 12297 during 2015 March 19-20. Recurrent EUV jets close to two filaments were detected along a large-scale coronal loop prior to the appearances of the tornadoes. Under the disturbances from the activities, the filaments continually ascended and finally interacted with the loops tracked by the jets. Subsequently, the structures of the filaments and the loop were merged together, probably via magnetic reconnections, and formed tornado-like structures with a long spiral arm. Our observations suggest that solar tornadoes can be triggered by the interaction between filaments and nearby coronal jets, which has rarely been reported before. At the earlier development phase of the first tornado, about 30 small-scale sub-jets appeared in the tornado’s arm, accompanied by local EUV brightenings. They have an ejection direction approximately vertical to the axis of the arm and a typical maximum speed of ˜280 km s-1. During the ruinations of the two tornadoes, fast plasma outflows from the strong EUV brightenings inside tornadoes are observed, in company with the untangling or unwinding of the highly twisted tornado structures. These observational features indicate that self reconnections probably occurred between the tangled magnetic fields of the tornadoes and resulted in the rapid disintegrations and disappearances of the tornadoes. According to the reconnection theory, we also derive the field strength of the tornado core to be ˜8 G.

Two Categories of Apparent Tornado-like Prominences

Science.gov (United States)

Martin, Sara F.; Venkataramanasastry, Aparna

2014-06-01

Two categories of solar prominences have been described in the literature as having a pattern of mass motions and/or a shape similar to terrestrial tornados. We first identify the two categories associated with prominences in the historic literature and then show that counterparts do exist for both in recent literature but one has not been called a tornado prominence. One category described as being similar to tornados is associated with the barbs of quiescent filaments but barbs appear to have rotational motion only under special conditions. H alpha Doppler observations from Helio Research confirm that this category is an illusion in our mind’s eye resulting from counterstreaming in the large barbs of quiescent filaments. The second category is a special case of rotational motion occurring during the early stages of some erupting prominences, in recent years called the roll effect in erupting prominences. In these cases, the eruption begins with the sideways rolling of the top of a prominence. As the eruption proceeds the rolling motion propagates down one leg or both legs of an erupting prominence depending on whether the eruption is asymmetric or symmetric respectively. As an asymmetric eruption proceeds, the longer lasting leg becomes nearly vertical and has true rotational motion. If only this phase of the eruption was observed, as in the historic cases, it was called a tornado prominence and spectra recorded in these cases provide proof of the rotational motion. When one observes an entire eruption which exhibits the rolling motion, as accomplished at Helio Research, the similarity to a tornado is lost because the event as a whole has quite a different nature and the analogy to a terrestrial tornado not longer appears suitable or helpful in understanding the observed and deduced physical processes. Our conclusion is that there are no solar prominences with motions that are usefully described as tornado or tornado-like events aside from the fun of observing

Modern tornado design of nuclear and other potentially hazardous facilities

International Nuclear Information System (INIS)

Stevenson, J.D.; Zhao, Y.

1996-01-01

Tornado wind loads and other tornado phenomena, including tornado missiles and differential pressure effects, have not usually been considered in the design of conventional industrial, commercial, or residential facilities in the United States; however, tornado resistance has often become a design requirement for certain hazardous facilities, such as large nuclear power plants and nuclear materials and waste storage facilities, as well as large liquefied natural gas storage facilities. This article provides a review of current procedures for the design of hazardous industrial facilities to resist tornado effects. 23 refs., 19 figs., 13 tabs

Cold-Season Tornadoes: Climatological, Meteorological, and Social Perspectives

Science.gov (United States)

Childs, Samuel J.

Tornadoes that occur during the cold season, defined here as November-February (NDJF), pose many unique societal risks. For example, people can be caught off-guard because in general one does not expect severe weather and tornadoes during winter months. The public can also be unsuspecting of significant weather due to the bustle of major holidays like Thanksgiving, Christmas, and New Year's, when most people are concerned with family activities and not thinking about the weather. Cold-season tornadoes also have a propensity to be nocturnal and occur most frequently in the South and Southeastern U.S., where variable terrain, inadequate resources, and a relatively high mobile home density add additional social vulnerabilities. Over the period 1953-2015 within a study domain of (25-42.5°N, 75-100°W), some 937 people lost their lives as a result of NDJF tornadoes. Despite this enhanced societal risk of cold-season tornadoes in the South, very little attention has been given to their meteorological characteristics and climate patterns, and public awareness of their potential impacts is lacking. This thesis aims to greatly advance the current state of knowledge of NDJF tornadoes by providing an in-depth investigation from three different science perspectives. First, a climatology of all (E)F1-(E)F5 NDJF tornadoes is developed, spanning the period 1953-2015 within a domain of (25-42.5°N, 75-100°W), in order to assess frequency and spatial changes over time. A large increasing trend in cold-season tornado occurrence is found across much of the Southeastern U.S., with the greatest uptick in Tennessee, while a decreasing trend is found across eastern Oklahoma. Spectral analysis reveals a cyclic pattern of enhanced NDJF counts every 3-7 years, coincident with the known period for ENSO. Indeed, La Nina episodes are found to be correlated with NDJF tornado counts, although a stronger teleconnection correlation exists with the Arctic Oscillation (AO), which explains 25% of

Family emergency preparedness plans in severe tornadoes.

Science.gov (United States)

Cong, Zhen; Liang, Daan; Luo, Jianjun

2014-01-01

Tornadoes, with warnings usually issued just minutes before their touchdowns, pose great threats to properties and people's physical and mental health. Few studies have empirically investigated the association of family emergency preparedness planning and observed protective behaviors in the context of tornadoes. The purpose of this study was to examine predictors for the action of taking shelter at the time of tornadoes. Specifically, this study investigated whether having a family emergency preparedness plan was associated with higher likelihood of taking shelter upon receiving tornado warnings. This study also examined the effects of socioeconomic status and functional limitations on taking such actions. A telephone survey based on random sampling was conducted in 2012 with residents in Tuscaloosa AL and Joplin MO. Each city experienced considerable damages, injuries, and casualties after severe tornadoes (EF-4 and EF-5) in 2011. The working sample included 892 respondents. Analysis was conducted in early 2013. Logistic regression identified emergency preparedness planning as the only shared factor that increased the likelihood of taking shelter in both cities and the only significant factor in Joplin. In Tuscaloosa, being female and white also increased the likelihood of taking shelter. Disability was not found to have an effect. This study provided empirical evidence on the importance of having a family emergency preparedness plan in mitigating the risk of tornadoes. The findings could be applied to other rapid-onset disasters. © 2013 American Journal of Preventive Medicine Published by American Journal of Preventive Medicine All rights reserved.

Re-interpreting Prominences Classified as Tornadoes

Science.gov (United States)

Martin, Sara F.; Venkataramanasastry, Aparna

2015-04-01

Some papers in the recent literature identify tornado prominences with barbs of quiescent prominences while papers in the much older historic literature include a second category of tornado prominence that does not correspond to a barb of a quiescent prominence. The latter are described as prominence mass rotating around a nearly vertical axis prior to its eruption and the rotation was verified by spectral measurements. From H alpha Doppler-shifted mass motions recorded at Helio Research or the Dutch Open Telescope, we illustrate how the apparent tornado-like motions, identified with barbs, are illusions in our mind’s eye resulting from poorly resolved counterstreaming threads of mass in the barbs of quiescent prominences. In contrast, we confirm the second category of rotational motion in prominences shortly before and during eruption. In addition, we identify this second category as part of the late phase of a phenomenon called the roll effect in erupting prominences. In these cases, the eruption begins with the sideways rolling of the top of a prominence. As the eruption proceeds the rolling motion propagates down one leg or both legs of the prominence depending on whether the eruption is asymmetric or symmetric respectively. As an asymmetric eruption continues, the longer lasting leg becomes nearly vertical and its rotational motion also continues. If only this phase of the eruption was observed, as in some historic cases, it was called a tornado prominence. However, when we now observe entire eruptions in time-lapse sequences, the similarity to terrestrial tornadoes is lost. We conclude that neither prominence barbs, that give the illusion of rotation, nor the cases of true rotational motion, in the legs of erupting prominences, are usefully described as tornado prominences when the complete prominence structure or complete erupting event is observed.

US tornadoes. Part 1: 70-year statistics

Science.gov (United States)

Fujita, T. T.

1987-01-01

If tornadoes were counted as the Gross National Product, no other country on the surface of the earth could come even close to the United States. During the recent 70 year period, the United States produced 31,054 tornadoes which left behind a cumulative path of 132,005 miles (212,396 km) which would circle the world 5.3 times along the equator. In completing the book, staff members of the Satellite and Mesometeorlogy Research Project (1961 to the present) played an important role in collecting, evaluating, and archiving the historical tornado data.

Predictors of compliance with tornado warnings issued in Joplin, Missouri, in 2011.

Science.gov (United States)

Paul, Bimal Kanti; Stimers, Mitchel; Caldas, Marcellus

2015-01-01

Joplin, a city in the southwest corner of Missouri, United States, suffered an EF-5 tornado in the late afternoon of 22 May 2011. This event, which claimed the lives of 162 people, represents the deadliest single tornado to strike the US since modern record-keeping began in 1950. This study examines the factors associated with responses to tornado warnings. Based on a post-tornado survey of survivors in Joplin, it reveals that tornado warnings were adequate and timely. Multivariate logistic regression identified four statistically significant determinants of compliance with tornado warnings: number of warning sources, whether respondents were at home when the tornado struck, past tornado experience, and gender. The findings suggest several recommendations, the implementation of which will further improve responses to tornado warnings. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

Physical Patterns Associated with 27 April 2011 Tornado Outbreak

Science.gov (United States)

Ramos, Fernanda; Salem, Thomas

2012-02-01

The National Weather Service office in Memphis, Tennessee has aimed their efforts to improve severe tornado forecasting. Everything is not known about tornadogenesis, but one thing is: tornadoes tend to form within supercell thunderstorms. Hence, 27 April 2011 and 25 May 2011 were days when a Tornado Outbreak was expected to arise. Although 22 tornadoes struck the region on 27 April 2011, only 1 impacted the area on 25 May 2011. In order to understand both events, comparisons of their physical features were made. These parameters were studied using the Weather Event Simulator system and the NOAA/NWS Storm Prediction database. This research concentrated on the Surface Frontal Analysis, NAM40 700mb Dew-Points, NAM80 250mb Wind Speed and NAM20 500mb Vorticity images as well as 0-6 km Shear, MUCAPE and VGP mesoscale patterns. As result of this research a Dry-Line ahead of a Cold Front, Dew-points 5C and higher, and high Vorticity values^ were synoptic patterns that influenced to the formation of supercell tornadoes. Finally, MUCAPE and VGP favored the possibility of tornadoes occurrence on 25 May 2011, but shear was the factor that made 27 April 2011 a day for a Tornado Outbreak weather event.

Statistical Models for Tornado Climatology: Long and Short-Term Views.

Science.gov (United States)

Elsner, James B; Jagger, Thomas H; Fricker, Tyler

2016-01-01

This paper estimates regional tornado risk from records of past events using statistical models. First, a spatial model is fit to the tornado counts aggregated in counties with terms that control for changes in observational practices over time. Results provide a long-term view of risk that delineates the main tornado corridors in the United States where the expected annual rate exceeds two tornadoes per 10,000 square km. A few counties in the Texas Panhandle and central Kansas have annual rates that exceed four tornadoes per 10,000 square km. Refitting the model after removing the least damaging tornadoes from the data (EF0) produces a similar map but with the greatest tornado risk shifted south and eastward. Second, a space-time model is fit to the counts aggregated in raster cells with terms that control for changes in climate factors. Results provide a short-term view of risk. The short-term view identifies a shift of tornado activity away from the Ohio Valley under El Niño conditions and away from the Southeast under positive North Atlantic oscillation conditions. The combined predictor effects on the local rates is quantified by fitting the model after leaving out the year to be predicted from the data. The models provide state-of-the-art views of tornado risk that can be used by government agencies, the insurance industry, and the general public.

l tornado che colpì la laguna di Venezia I ' l l Settembre 1970 Qualche considerazione intorno alla teoria elettrica dei tornado

Directory of Open Access Journals (Sweden)

R. JANESELLI

1972-06-01

Full Text Available After a short description of the disastrous effects of the
tornado which struck the Venice lagoon on September 11, 1970, the principal
theories which in the centuries tried to account for the origin of such
terrible vortexes, are reviewed. In particular, some remarks are given about
the electrical theory of the tornadoes. It seems to the author that some features
would be explained in a simple way by considering the tornado as a
convectivo cell with electric currents of high intensity. Finally, after recalling
the meteorological conditions preceding the tornado of September 11,
its chief features are described.

Dynamical analysis and visualization of tornadoes time series.

Directory of Open Access Journals (Sweden)

António M Lopes

Full Text Available In this paper we analyze the behavior of tornado time-series in the U.S. from the perspective of dynamical systems. A tornado is a violently rotating column of air extending from a cumulonimbus cloud down to the ground. Such phenomena reveal features that are well described by power law functions and unveil characteristics found in systems with long range memory effects. Tornado time series are viewed as the output of a complex system and are interpreted as a manifestation of its dynamics. Tornadoes are modeled as sequences of Dirac impulses with amplitude proportional to the events size. First, a collection of time series involving 64 years is analyzed in the frequency domain by means of the Fourier transform. The amplitude spectra are approximated by power law functions and their parameters are read as an underlying signature of the system dynamics. Second, it is adopted the concept of circular time and the collective behavior of tornadoes analyzed. Clustering techniques are then adopted to identify and visualize the emerging patterns.

Acoustic detection, tracking, and characterization of three tornadoes.

Science.gov (United States)

Frazier, William Garth; Talmadge, Carrick; Park, Joseph; Waxler, Roger; Assink, Jelle

2014-04-01

Acoustic data recorded at 1000 samples per second by two sensor arrays located at ranges of 1-113 km from three tornadoes that occurred on 24 May 2011 in Oklahoma are analyzed. Accurate bearings to the tornadoes have been obtained using beamforming methods applied to the data at infrasonic frequencies. Beamforming was not viable at audio frequencies, but the data demonstrate the ability to detect significant changes in the shape of the estimated power spectral density in the band encompassing 10 Hz to approximately 100 Hz at distances of practical value from the sensors. This suggests that arrays of more closely spaced sensors might provide better bearing accuracy at practically useful distances from a tornado. Additionally, a mathematical model, based on established relationships of aeroacoustic turbulence, is demonstrated to provide good agreement to the estimated power spectra produced by the tornadoes at different times and distances from the sensors. The results of this analysis indicate that, qualitatively, an inverse relationship appears to exist between the frequency of an observed peak of the power spectral density and the reported tornado intensity.

Dynamical analysis and visualization of tornadoes time series.

Science.gov (United States)

Lopes, António M; Tenreiro Machado, J A

2015-01-01

In this paper we analyze the behavior of tornado time-series in the U.S. from the perspective of dynamical systems. A tornado is a violently rotating column of air extending from a cumulonimbus cloud down to the ground. Such phenomena reveal features that are well described by power law functions and unveil characteristics found in systems with long range memory effects. Tornado time series are viewed as the output of a complex system and are interpreted as a manifestation of its dynamics. Tornadoes are modeled as sequences of Dirac impulses with amplitude proportional to the events size. First, a collection of time series involving 64 years is analyzed in the frequency domain by means of the Fourier transform. The amplitude spectra are approximated by power law functions and their parameters are read as an underlying signature of the system dynamics. Second, it is adopted the concept of circular time and the collective behavior of tornadoes analyzed. Clustering techniques are then adopted to identify and visualize the emerging patterns.

Tornado missile impact study

International Nuclear Information System (INIS)

McDonald, J.R.

1991-01-01

UCRL-15910 specifies wind and tornado missiles for moderate- and high-hazard DOE facilities. Wall-barrier specimens have been tested at the Tornado Missile Impact Facility at Texas Tech University. The facility has an air-activated tornado missile cannon capable of firing 2x4 timber planks weighing 12 lb at speeds up to 150 mph and 3-in-diameter steel pipes weighing 75 lb at speeds to 7 5 mph. Wall barriers tested to date include reinforced concrete walls from 4-in. to 10-in. thick; 8-in. and 12-in. walls of reinforced concrete masonry units (CMU); two other masonry wall configurations consisting of an 8-in. CMU with a 4-in. clay-brick veneer and a 10-in. composite wall with two wythes of 4-in. clay brick. The impact test series is designed to determine the impact speed that will produce backface spall of each wall barrier. A set of 15 wall sections has been constructed and tested at this time. Preliminary finding suggest that all cells of CMU walls must be grouted to prevent missile penetration. Walls recommended in the workshop on UCRL-15910 provide acceptable protection if cracking can be accepted

Tornado missiles protections taken at the Ikata NPP of SEPCO

International Nuclear Information System (INIS)

Ikeda, Kazutoyo; Takagi, Toshimitsu; Inoue, Haruhisa; Yoshida, Hisao; Moriuchi, Takehiro

2014-01-01

On July 8, 2013, the new regulatory requirements for commercial power reactors got in force. Based on a concept of 'Defense-in-depth', essential importance was placed on the third and fourth layers of defense and prevention of simultaneous loss of all safety functions due to common causes. In this regards, the previous assumptions on the impact of earthquakes, tsunamis and other external events such as volcanic eruptions, tornadoes and forest fires were re-evaluated, and countermeasures for nuclear safety against these external events were decided to be enhanced. For tornado, Nuclear Regulation Authority promulgated the 'Assessment Guide for Tornado Effect on Nuclear Power Plants' to evaluate the effect of tornadoes. This paper will introduce the outline of evaluation cases of tornado effect, and tornado missiles protections taken at the Ikata Unit 3 Nuclear Power Plant (for actual case studies). (author)

Examining social, physical, and environmental dimensions of tornado vulnerability in Texas.

Science.gov (United States)

Siebeneck, Laura

2016-01-01

To develop a vulnerability model that captures the social, physical, and environmental dimensions of tornado vulnerability of Texas counties. Guided by previous research and methodologies proposed in the hazards and emergency management literature, a principle components analysis is used to create a tornado vulnerability index. Data were gathered from open source information available through the US Census Bureau, American Community Surveys, and the Texas Natural Resources Information System. Texas counties. The results of the model yielded three indices that highlight geographic variability of social vulnerability, built environment vulnerability, and tornado hazard throughout Texas. Further analyses suggest that counties with the highest tornado vulnerability include those with high population densities and high tornado risk. This article demonstrates one method for assessing statewide tornado vulnerability and presents how the results of this type of analysis can be applied by emergency managers towards the reduction of tornado vulnerability in their communities.

Theoretical tornado vortex model for nuclear plant design

International Nuclear Information System (INIS)

Sun, C.N.; Barnett, R.O.; Burdette, E.G.

1977-01-01

A simplified tornado vortex model is defined using fluid dynamics theory. Beginning with the Navier-Stokes equations of motion for an incompressible fluid and simpifying in a way consistent with a tornado wind field, develops the well-known cyclostrophic wind equation referred to by Hoecker and another equation which defines the tangential velocity profile. Together, they define a simplified tornado vertex model of which the Rankine and Hoecker vortices are special cases. Practical implications of the results obtained are discussed. (Auth.)

Spatial Distributions of Tropical Cyclone Tornadoes by Intensity and Size Characteristics

Directory of Open Access Journals (Sweden)

Todd W. Moore

2017-08-01

Full Text Available Tropical cyclones that make landfall often spawn tornadoes. Previous studies have shown that these tornadoes are not uniformly distributed in the United States or in the tropical cyclone environment. They show that tornadoes tend to occur relatively close to the coastline and that they tend to cluster to the east-of-center in the tropical cyclone environment, particularly in the northeast and east-of-center quadrants. This study contributes to these studies by analyzing the spatial distributions of tropical cyclone tornadoes by intensity, path length, path width, and the damage potential index. The analyses confirm that most tornadoes occur relatively close to the coastline, but show that stronger tornadoes with larger paths are disproportionately common farther inland. They also confirm that the highest amount of activity is located within the northeast and east-of-center quadrants and show that the most potentially damaging tornadoes cluster in a sub region near the intersection of these two quadrants.

Tornadoes: Nature's Most Violent Storms. A Preparedness Guide Including Safety Information for Schools.

Science.gov (United States)

American National Red Cross, Washington, DC.

This preparedness guide explains and describes tornadoes, and includes safety information for schools. A tornado is defined as a violently rotating column of air extending from a thunderstorm to the ground. The guide explains the cause of tornadoes, provides diagrams of how they form, describes variations of tornadoes, and classifies tornadoes by…

Design of convolutional tornado code

Science.gov (United States)

Zhou, Hui; Yang, Yao; Gao, Hongmin; Tan, Lu

2017-09-01

As a linear block code, the traditional tornado (tTN) code is inefficient in burst-erasure environment and its multi-level structure may lead to high encoding/decoding complexity. This paper presents a convolutional tornado (cTN) code which is able to improve the burst-erasure protection capability by applying the convolution property to the tTN code, and reduce computational complexity by abrogating the multi-level structure. The simulation results show that cTN code can provide a better packet loss protection performance with lower computation complexity than tTN code.

Tornadoes and related damage costs: statistical modeling with a semi-Markov approach

OpenAIRE

Corini, Chiara; D'Amico, Guglielmo; Petroni, Filippo; Prattico, Flavio; Manca, Raimondo

2015-01-01

We propose a statistical approach to tornadoes modeling for predicting and simulating occurrences of tornadoes and accumulated cost distributions over a time interval. This is achieved by modeling the tornadoes intensity, measured with the Fujita scale, as a stochastic process. Since the Fujita scale divides tornadoes intensity into six states, it is possible to model the tornadoes intensity by using Markov and semi-Markov models. We demonstrate that the semi-Markov approach is able to reprod...

Touchable Tornadoes

Science.gov (United States)

Gilhousen, David

2004-01-01

In this article, the author discusses a tornado-producing machine that he used in teacher-led, student assisted demonstrations in order to reinforce concepts learned during a unit on weather. The machine, or simulator, was powered by a hair dryer, fan, and cool-mist humidifier. The machine consists of a demonstration table containing a plenum box,…

A forensic re-analysis of one of the deadliest European tornadoes

Science.gov (United States)

Holzer, Alois M.; Schreiner, Thomas M. E.; Púčik, Tomáš

2018-06-01

Extremely rare events with high potential impact, such as violent tornadoes, are of strong interest for climatology and risk assessment. In order to obtain more knowledge about the most extreme events, it is vital to study historical cases. The purpose of this paper is twofold: (1) to demonstrate how a windstorm catastrophe that happened 100 years ago, such as the Wiener Neustadt, Lower Austria, tornado on 10 July 1916, can be successfully re-analyzed using a forensic approach, and (2) to propose a repeatable working method for assessing damage and reconstructing the path and magnitude of local windstorm and tornado cases with sufficient historical sources. Based on the results of the forensic re-analyses, a chronology of the tornado impact is presented, followed by a description of the key tornado characteristics: a maximum intensity rating of F4, a damage path length of 20 km and a maximum visible tornado diameter of 1 km. Compared to a historical scientific study published soon after the event, additional new findings are presented, namely the existence of two predecessor tornadoes and a higher number of fatalities: at least 34 instead of 32. While the storm-scale meteorology could not be reconstructed, rich damage data sources for the urban area of Wiener Neustadt facilitated a detailed analysis of damage tracks and wind intensities within the tornado. The authors postulate the requirement for an International Fujita Scale to rate tornadoes globally in a consistent way, based on comparable damage indicators.

Two Solar Tornadoes Observed with the Interface Region Imaging Spectrograph

Science.gov (United States)

Yang, Zihao; Tian, Hui; Peter, Hardi; Su, Yang; Samanta, Tanmoy; Zhang, Jingwen; Chen, Yajie

2018-01-01

The barbs or legs of some prominences show an apparent motion of rotation, which are often termed solar tornadoes. It is under debate whether the apparent motion is a real rotating motion, or caused by oscillations or counter-streaming flows. We present analysis results from spectroscopic observations of two tornadoes by the Interface Region Imaging Spectrograph. Each tornado was observed for more than 2.5 hr. Doppler velocities are derived through a single Gaussian fit to the Mg II k 2796 Å and Si IV 1393 Å line profiles. We find coherent and stable redshifts and blueshifts adjacent to each other across the tornado axes, which appears to favor the interpretation of these tornadoes as rotating cool plasmas with temperatures of 104 K–105 K. This interpretation is further supported by simultaneous observations of the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, which reveal periodic motions of dark structures in the tornadoes. Our results demonstrate that spectroscopic observations can provide key information to disentangle different physical processes in solar prominences.

Estimating dispersion from a tornado vortex and mesocyclone

International Nuclear Information System (INIS)

Weber, A.H.; Hunter, C.H.

1996-06-01

Atmospheric dispersion modeling is required to ensure that a postulated breach in radionuclide storage containers at the Savannah River Site (SRS) from a tornado strike of Fujita-scale intensity F2 or higher will not result in an unacceptable dose to individuals. Fujita-scale tornado descriptions are included in Appendix A of this report. Dispersion models previously used at SRS for estimating dispersion following a tornado strike were developed by D.W. Pepper in 1975 (DP-1387, Dispersion of Small Particles) and H.R. Haynes and D.W. Taylor in 1983 (DPST-82-982, Estimating Doses from Tornado Winds). Research conducted in 1983 on the formation and evolution of tornadic thunderstorms has lead to a more complete understanding of the tornado vortex and associated persistent updraft and downdraft regions within the parent thunderstorm. To ensure that appropriate, contemporary methods are used for safety analysis, the Pepper model and the Haynes and Taylor model were evaluated with respect to current knowledge of circulations within tornadic thunderstorms. Pepper's model is complex numerically but contains most of the desired physical parameterizations. Haynes and Taylor's model is used with the Puff-Plume model (an emergency response model on the Weather INformation and Display System at SRS) and has provisions for radionuclide deposition and rainout. Haynes and Taylor assumed heavy rain following the tornado for a period of ten minutes, followed by a lighter rain for another ten minutes, then no rain for the period when the material is transported to 100 km downwind. However, neither model incorporates the effects of a nearby thunderstorm downdraft

A solar tornado triggered by flares?

OpenAIRE

Panesar, N. K.; Innes, D. E.; Tiwari, S. K.; Low, B. C.

2013-01-01

Context. Solar tornados are dynamical, conspicuously helical magnetic structures that are mainly observed as a prominence activity. Aims. We investigate and propose a triggering mechanism for the solar tornado observed in a prominence cavity by SDO/AIA on September 25, 2011. Methods. High-cadence EUV images from the SDO/AIA and the Ahead spacecraft of STEREO/EUVI are used to correlate three flares in the neighbouring active-region (NOAA 11303) and their EUV waves with the dynamical de...

A forensic re-analysis of one of the deadliest European tornadoes

Directory of Open Access Journals (Sweden)

A. M. Holzer

2018-06-01

Full Text Available Extremely rare events with high potential impact, such as violent tornadoes, are of strong interest for climatology and risk assessment. In order to obtain more knowledge about the most extreme events, it is vital to study historical cases. The purpose of this paper is twofold: (1 to demonstrate how a windstorm catastrophe that happened 100 years ago, such as the Wiener Neustadt, Lower Austria, tornado on 10 July 1916, can be successfully re-analyzed using a forensic approach, and (2 to propose a repeatable working method for assessing damage and reconstructing the path and magnitude of local windstorm and tornado cases with sufficient historical sources. Based on the results of the forensic re-analyses, a chronology of the tornado impact is presented, followed by a description of the key tornado characteristics: a maximum intensity rating of F4, a damage path length of 20 km and a maximum visible tornado diameter of 1 km. Compared to a historical scientific study published soon after the event, additional new findings are presented, namely the existence of two predecessor tornadoes and a higher number of fatalities: at least 34 instead of 32. While the storm-scale meteorology could not be reconstructed, rich damage data sources for the urban area of Wiener Neustadt facilitated a detailed analysis of damage tracks and wind intensities within the tornado. The authors postulate the requirement for an International Fujita Scale to rate tornadoes globally in a consistent way, based on comparable damage indicators.

Mortality from a tornado outbreak, Alabama, April 27, 2011.

Science.gov (United States)

Chiu, Cindy H; Schnall, Amy H; Mertzlufft, Caitlin E; Noe, Rebecca S; Wolkin, Amy F; Spears, Jeanne; Casey-Lockyer, Mary; Vagi, Sara J

2013-08-01

We describe the demographics of the decedents from the tornado outbreak in Alabama on April 27, 2011; examine the circumstances of death surrounding these fatalities; and identify measures to prevent future tornado-related fatalities. We collected information about the decedents from death certificates, disaster-related mortality surveillance, and interview data collected by American Red Cross volunteers from the decedent's families. We describe demographic characteristics, circumstances and causes of death, and sheltering behaviors before death. Of the 247 fatalities, females and older adults were at highest risk for tornado-related deaths. Most deaths were directly related to the tornadoes, on scene, and trauma-related. The majority of the deceased were indoors in single-family homes. Word of mouth was the most common warning mechanism. This tornado event was the third deadliest in recent US history. Our findings support the need for local community shelters, enhanced messaging to inform the public of shelter locations, and encouragement of word-of-mouth warnings and personal and family preparedness planning, with a special focus on assisting vulnerable individuals in taking shelter.

School interventions after the Joplin tornado.

Science.gov (United States)

Kanter, Robert K; Abramson, David

2014-04-01

To qualitatively describe interventions by schools to meet children's needs after the May 2011 Joplin, Missouri tornado. Qualitative exploratory study conducted six months after the tornado. Key informant interviews with school staff (teachers, psychologists, guidance counselor, nurse, principal), public health official, and physicians. After the tornado, school staff immediately worked to contact every enrolled child to provide assistance and coordinate recovery services. Despite severe damage to half of the city's schools, the decision was made to reopen schools at the earliest possible time to provide a safe, reassuring environment and additional services. An expanded summer school session emphasized child safety and emotional wellbeing. The 2011-2012 school year began on time, less than three months after the disaster, using temporary facilities. Displaced children were bused to their usual schools regardless of their new temporary residence locations. In just-in-time training sessions, teachers developed strategies to support students and staff experiencing anxiety or depression. Certified counselors conducted school-based, small-group counseling for students. Selective referrals were made to community mental health providers for children with greatest needs. Evidence from Joplin adds to a small body of empirical experience demonstrating the important contribution of schools to postdisaster community recovery. Despite timely and proactive services, many families and children struggled after the tornado. Improvements in the effectiveness of postdisaster interventions at schools will follow from future scientific evidence on optimal approaches.

Dual-Polarimetric Radar-Based Tornado Debris Paths Associated with EF-4 and EF-5 Tornadoes over Northern Alabama During the Historic Outbreak of 27 April 2011

Science.gov (United States)

Carey, Lawrence D.; Schultz, Chrstopher J.; Schultz, Elise V.; Petersen, Walter A.; Gatlin, Patrick N.; Knupp, Kevin R.; Molthan, Andrew L.; Jedlovec, Gary J.; Darden, Christopher B.

2012-01-01

An historic tornado and severe weather outbreak devastated much of the southeastern United States between 25 and 28 April 2011. On 27 April 2011, northern Alabama was particularly hard hit by a large number of tornadoes, including several that reached EF-4 and EF-5 on the Enhanced Fujita damage scale. In northern Alabama alone, there were approximately 100 fatalities and hundreds of more people who were injured or lost their homes during the havoc caused by these violent tornadic storms. Two long-track and violent (EF-4 and EF-5) tornadoes occurred within range of the University of Alabama in Huntsville (UAHuntsville) Advanced Radar for Meteorological and Operational Research (ARMOR, C-band dual-polarimetric). A unique capability of dual-polarimetric radar is the near-real time identification of lofted debris associated with ongoing tornadoes on the ground. The focus of this paper is to analyze the dual-polarimetric radar-inferred tornado debris signatures and identify the associated debris paths of the long-track EF-4 and EF-5 tornadoes near ARMOR. The relative locations of the debris and damage paths for each tornado will be ascertained by careful comparison of the ARMOR analysis with NASA MODIS (Moderate Resolution Imaging Spectroradiometer) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite imagery of the tornado damage scenes and the National Weather Service tornado damage surveys. With the ongoing upgrade of the WSR-88D (Weather Surveillance Radar 1988 Doppler) operational network to dual-polarimetry and a similar process having already taken place or ongoing for many private sector radars, dual-polarimetric radar signatures of tornado debris promise the potential to assist in the situational awareness of government and private sector forecasters and emergency managers during tornadic events. As such, a companion abstract (Schultz et al.) also submitted to this conference explores The use of dual-polarimetric tornadic debris

Coupling Between Doppler Radar Signatures and Tornado Damage Tracks

Science.gov (United States)

Jedlovec, Gary J.; Molthan, Andrew L.; Carey, Lawrence; Carcione, Brian; Smith, Matthew; Schultz, Elise V.; Schultz, Christopher; Lafontaine, Frank

2011-01-01

On April 27, 2011, the southeastern United States was raked with several episodes of severe weather. Numerous tornadoes caused extensive damage, and tragically, the deaths of over 300 people. In Alabama alone, there were 61 confirmed tornados, 4 of them produced EF5 damage, and several were on the ground an hour or more with continuous damage tracks exceeding 80km. The use of Doppler radars covering the region provided reflectivity and velocity signatures that allowed forecasters to monitors the severe storms from beginning to end issuing hundreds of severe weather warnings throughout the day. Meteorologists from the the NWS performed extensive surveys to assess the intensity, duration, and ground track of tornadoes reported during the event. Survey activities included site visits to the affected locations, analysis of radar and satellite data, aerial surveys, and interviews with eyewitnesses. Satellite data from NASA's MODIS and ASTER instruments played a helpful role in determining the location of tornado damage paths and in the assessment. High resolution multispectral and temporal composites helped forecasters corroborate their damage assessments, determine starting and ending points for tornado touchdowns, and helped to provide forecasters with a better big-picture view of the damage region. The imagery also helped to separate damage from the April 27th tornados from severe weather that occurred earlier that month. In a post analysis of the outbreak, tornado damage path signatures observed in the NASA satellite data have been correlated to "debris ball" signatures in the NWS Doppler radars and a special ARMOR dual-polarization radar operated by the University of Alabama Huntsville during the event. The Doppler radar data indicates a circular enhanced reflectivity signal and rotational couplet in the radial velocity likely associated with the tornado that is spatially correlated with the damage tracks in the observed satellite data. An algorithm to detect and

A rational method to evaluate tornado-borne missile speed in nuclear power plants. Validation of a numerical code based on Fujita's tornado model

International Nuclear Information System (INIS)

Eguchi, Yuzuru; Sugimoto, Soichiro; Hattori, Yasuo; Hirakuchi, Hiromaru

2015-01-01

Explanation is given about a rational method to evaluate tornado-borne missile speed, flight distance and flight height to be used for safety design of a nuclear power plant. In the method, the authors employed Fujita's DBT-77 model as a tornado wind model to take the near-ground tornado wind profile into account. A liftoff model of an object on the ground was developed by conservatively modeling the lift force due to ground effect. The wind field model and the liftoff model have been compiled together with a conventional flight model into a computer code, named TONBOS. In this study, especially, the code is verified for one- and two-dimensional free-fall problems as well as a case of 1957 Dallas tornado wind field model, whose solutions are theoretically or numerically known. Finally, the code is validated by typical car behaviors characterized by tornado wind speeds of the enhanced Fujita scale, as well as by an actual event where a truck was blown away by a tornado which struck a part of the town of Saroma, Hokkaido in November, 2006. (author)

Tornado-resistance design for the nuclear safety structure of Qinshan Nuclear Power Plant

International Nuclear Information System (INIS)

Xia Zufeng.

1987-01-01

The primary design consideration of anti-tornado of the nuclear safety structure of Qinshan Nuclear Power Plant is briefly presented. It mainly includes estimating the probability of tornado arising in the site, ascertaining the design requirments of the anti-tornado structures and deciding the tornado load acted on the structures

Magnetic traps with a sperical separatrix: Tornado traps

International Nuclear Information System (INIS)

Peregood, B.P.; Lehnert, B.

1979-11-01

A review is given on the features of magnetic traps with a spherical separatrix, with special emphesis on Tornado spiral coil configurations. The confinement and heating of static plasmas in Tornado traps is treated, including the topology of the magnetic field structure, the magneto-mechanical properties of the magnetic coil system, as well as the particle orbits and plasma behaviour in these traps. In additio, the mode of rotating plasma operation by crossed electric and magnetic fields is being described. The results of experiments on static and rotating plasmas are summarized, and conclusions are drawn about future possibilities of Tornado traps for the creation and containment of hot plasmas. (author)

Magnetic traps with a spherical separatrix: Tornado traps

International Nuclear Information System (INIS)

Peregood, B.P.; Lehnert, B.

1981-01-01

A review is given on the features of magnetic traps with a spherical separatrix, with special emphasis on Tornado spiral coil configurations. The confinement and heating of static plasms in Tornado traps is treated, including the topology of the magnetic field structure, the magneto-mechanical properties of the magnetic coil system, as well as the particle orbits and plasma behaviour in these traps. In addition, the mode of rotating plasma operation by crossed electric and magnetic fields is described. The results of experiments on static and rotating plasmas are summarized, and conclusions are drawn about future possibilities of Tornado traps in the creation and containment of hot plasmas. (orig.)

Community Post-Tornado Support Groups: Intervention and Evaluation.

Science.gov (United States)

McCammon, Susan; And Others

Post-tornado support groups were organized by the Greene County, North Carolina disaster coordinators and the Pitt County outreach workers from the Community Mental Health Center sponsored tornado follow-up project. The most significant intervention used was the emphasis on creating a climate of group support by establishing a forum for…

Tornado from Texas.

Science.gov (United States)

Vail, Kathleen

1996-01-01

Santa Fe School Superintendent Yvonne Gonzales, the "Texas Tornado," was hired to fix a 40% student-dropout rate and a white/Hispanic gap in achievement test scores. Gonzales is an avid integrationist; relies on humor, appeasement, and persuasion tactics; and has alienated some school employees by increasing central office…

Tornadoes: A Center Approach.

Science.gov (United States)

Christman-Rothlein, Liz; Meinbach, Anita M.

1981-01-01

Information is given on how to put together a learning center. Discusses information and activity packets for a complete learning center on tornadoes including objectives, directions, materials, photographs of physical arrangements, and posttest. (DC)

A Bayesian modelling framework for tornado occurrences in North America.

Science.gov (United States)

Cheng, Vincent Y S; Arhonditsis, George B; Sills, David M L; Gough, William A; Auld, Heather

2015-03-25

Tornadoes represent one of nature's most hazardous phenomena that have been responsible for significant destruction and devastating fatalities. Here we present a Bayesian modelling approach for elucidating the spatiotemporal patterns of tornado activity in North America. Our analysis shows a significant increase in the Canadian Prairies and the Northern Great Plains during the summer, indicating a clear transition of tornado activity from the United States to Canada. The linkage between monthly-averaged atmospheric variables and likelihood of tornado events is characterized by distinct seasonality; the convective available potential energy is the predominant factor in the summer; vertical wind shear appears to have a strong signature primarily in the winter and secondarily in the summer; and storm relative environmental helicity is most influential in the spring. The present probabilistic mapping can be used to draw inference on the likelihood of tornado occurrence in any location in North America within a selected time period of the year.

Preliminar calculation of tornado risk in the site of Ipero

Energy Technology Data Exchange (ETDEWEB)

Pacheco, Rafael R.; Costa, Saulo Barros, E-mail: rafael.rade@ctmsp.mar.mil.br, E-mail: saulo.costa@ctmsp.mar.mil.br [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil); Andrade, Delvonei A., E-mail: delvonei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

General Design Criterion (GDC) 2 to 10 CFR 50 requires that 'structures, systems, and components that are important to safety shall be designed to withstand the effects of natural phenomena, such as tornadoes, without loss of capability to perform their safety functions'. According to Regulatory Guide 1.76, the design-basis intensity of a tornado for a nuclear power plant shall not exceed the intensity of the strongest tornado that occurs with the frequency of 10-7/years. Reinforcing the plant to achieve this goal represents a high increase in the costs of the project, and correspondently increase in the time required to have it commissioned. This way, the right definition of tornado risk in a site would represent savings in money for the project and in time for the licensing of a nuclear power plants. This works aims to establish a preliminary calculation of the tornado risk in the site of Ipero, where will work LABGENE from Brazilian Navy, and RMB from CNEN. (author)

The assessment of tornado missile hazard to nuclear power plants

International Nuclear Information System (INIS)

Goodman, J.; Koch, J.E.

1983-01-01

Numerical methods and computer codes for assessing tornado missile hazards to nuclear power plants are developed. Due to the uncertainty and randomness of tornado and tornado-generated missiles' characteristics, the damage probability of targets has a highly spread distribution. The proposed method is useful for assessing the risk of not providing protection to some nonsafety-related targets whose failure can create a hazard to the safe operation of nuclear power plants

An Analysis of Operational Total Lightning Data During Long-Track Tornadoes

Science.gov (United States)

Carcione, Brian C.; Stano, Geoffrey T.

2012-01-01

The 27 April 2011 tornado outbreak brought three distinct waves of tornadic thunderstorms to portions of Mississippi, Alabama, Tennessee, and Georgia, striking the Tennessee Valley of north Alabama and southern Tennessee particularly hard. A total of 42 tornado paths were surveyed across the fourteen county area covered by the National Weather Service (NWS) forecast office in Huntsville, Alabama. Ten of these tornadoes were on the ground for at least 20 miles, two had total path lengths over 130 miles, and six tornadoes were classified as violent (EF-4 or EF-5 on the Enhanced Fujita Scale). Many of these tornadoes occurred within the domain of the North Alabama Lightning Mapping Array (NALMA), a ground-based total lightning detection network owned and operated by the NASA Marshall Space Flight Center. Since 2003, the NASA Short-term Prediction Research and Transition Center has supplied data from NALMA in real time to NWS forecast offices in Huntsville, Knoxville/Tri-Cities, Birmingham, and Nashville. Previous research has documented the utility of total lightning information in predicting tornadogenesis, particularly when combined with other remote sensing tools. Basic warning decision-making during events such as 27 April is not the most difficult part of the process; instead, the focus of warning meteorologists shifts to looking for changes in intensity or possible particularly dangerous situations, since doppler radar velocity data often cannot distinguish between weak and strong tornadoes. To that end, this research attempts to determine if any correlation exists between flash densities of the longest-tracked tornadoes over time, and the surveyed wind speeds of the tornadoes. The long-track EF-5 tornado which struck the Hackleburg, Phil Campbell, and Tanner communities in north Alabama was the primary focus of this research due to its intensity and extended life cycle. However, not all tornadoes were available for total lightning analysis due to widespread

Tornadoes and related damage costs: statistical modelling with a semi-Markov approach

Directory of Open Access Journals (Sweden)

Guglielmo D’Amico

2016-09-01

Full Text Available We propose a statistical approach to modelling for predicting and simulating occurrences of tornadoes and accumulated cost distributions over a time interval. This is achieved by modelling the tornado intensity, measured with the Fujita scale, as a stochastic process. Since the Fujita scale divides tornado intensity into six states, it is possible to model the tornado intensity by using Markov and semi-Markov models. We demonstrate that the semi-Markov approach is able to reproduce the duration effect that is detected in tornado occurrence. The superiority of the semi-Markov model as compared to the Markov chain model is also affirmed by means of a statistical test of hypothesis. As an application, we compute the expected value and the variance of the costs generated by the tornadoes over a given time interval in a given area. The paper contributes to the literature by demonstrating that semi-Markov models represent an effective tool for physical analysis of tornadoes as well as for the estimation of the economic damages to human things.

Electrical Characteristics of Simulated Tornadoes and Dust Devils

Science.gov (United States)

Zimmerman, Michael I.; Farrell, William M.; Barth, E. L.; Lewellen, W. S.; Perlongo, N. J.; Jackson, T. L.

2012-01-01

It is well known that tornadoes and dust devils have the ability to accumulate significant, visible clouds of debris. Collisions between sand-like debris species produce different electric charges on different types of grains, which convect along different trajectories around the vortex. Thus, significant charge separations and electric currents are possible, which as the vortex fluctuates over time are thought to produce ULF radiation signatures that have been measured in the field. These electric and magnetic fields may contain valuable information about tornado structure and genesis, and may be critical in driving electrochemical processes within dust devils on Mars. In the present work, existing large eddy simulations of debris-laden tornadoes performed at West Virginia University are coupled with a new debris-charging and advection code developed at Goddard Space Flight Center to investigate the detailed (meter-resolution) fluid-dynamic origins of electromagnetic fields within terrestrial vortices. First results are presented, including simulations of the electric and magnetic fields that would be observed by a near-surface, instrument-laden probe during a direct encounter with a tornado.

Vulnerability Assessment of the nuclear power plant Vandellos II before a tornado; Evaluacion de vulnerabilidad de C.N. Vandellos II ante tornado

Energy Technology Data Exchange (ETDEWEB)

Fernandez, A.; Encabo, J.; Vaz-Romero, A.; Moran, M. A.; Roch, M.; Nicolas, P.; Barrera, N.

2010-07-01

The purpose of this work was the study of vulnerability to tornado event Vandellos II NPP. To do this, we have evaluated all structures (buildings), security systems and components to the installation of wind stresses, depression and impact of projectiles, generated by a tornado on the site.

Assessment guide for tornado effect on Nuclear Power Plants (draft) with its commentaries

International Nuclear Information System (INIS)

Inoue, Hiroto; Fukunishi, Shiro; Suzuki, Tetsuo

2013-10-01

In the context of a severe accident at the Fukushima Daiichi Nuclear Power Station (NPS) operated by the Tokyo Electric Power Company (TEPCO) due to the 2011 off the Pacific coast of Tohoku Earthquake and Tsunami, Nuclear Regulation Authority (NRA) was established on September 19, 2012 under the relevant law. After that NRA organized a task force for studying new regulatory standards for nuclear power plants (NPPs) in consideration of lessons learned from the severe accident at Fukushima. In the task force open meeting, through discussing about design basis external natural events which should be considered in the new regulatory standards, tornado was newly introduced into new regulatory standards as an external natural event. Based on the decision that tornado was newly introduced into new regulatory standards, the Secretariat of the Nuclear Regulation Authority (SNRA) commissioned the Japan Nuclear Energy Safety Organization (JNES) to study an assessment guide for tornado effect on NPPs intended to be used for an official safety review for a NPP construction. JNES organized Sectional Committee for Tornado Effect Assessment Guide consisting of experts in meteorology and wind engineering fields, discussing about assessment methods for tornado effect on NPPs, draft version of the assessment guide for tornado effect on NPPs was completed on April 4, 2013, and JNES submitted the draft guide to SNRA on the same date. After that NRA called for public comments for the draft version of the assessment guide, the draft version of the assessment guide was partly amended taking posted public comments account, and tornado effect assessment guide was officially released on June 19, 2013. Contents in this paper are as follows, assessment guide for tornado effect on NPPs (Draft version on April 4, 2013), supplementary documents, calculation examples, and future tasks for further improved reliability of tornado effect assessment on NPPs. This draft guide consists of six chapters

Assessment guide for tornado effect on Nuclear Power Plants (draft) with its commentaries

Energy Technology Data Exchange (ETDEWEB)

Inoue, Hiroto; Fukunishi, Shiro; Suzuki, Tetsuo [Japan Nuclear Energy Safety Organization, Seismic Safety Department, Tokyo (Japan)

2013-10-15

In the context of a severe accident at the Fukushima Daiichi Nuclear Power Station (NPS) operated by the Tokyo Electric Power Company (TEPCO) due to the 2011 off the Pacific coast of Tohoku Earthquake and Tsunami, Nuclear Regulation Authority (NRA) was established on September 19, 2012 under the relevant law. After that NRA organized a task force for studying new regulatory standards for nuclear power plants (NPPs) in consideration of lessons learned from the severe accident at Fukushima. In the task force open meeting, through discussing about design basis external natural events which should be considered in the new regulatory standards, tornado was newly introduced into new regulatory standards as an external natural event. Based on the decision that tornado was newly introduced into new regulatory standards, the Secretariat of the Nuclear Regulation Authority (SNRA) commissioned the Japan Nuclear Energy Safety Organization (JNES) to study an assessment guide for tornado effect on NPPs intended to be used for an official safety review for a NPP construction. JNES organized Sectional Committee for Tornado Effect Assessment Guide consisting of experts in meteorology and wind engineering fields, discussing about assessment methods for tornado effect on NPPs, draft version of the assessment guide for tornado effect on NPPs was completed on April 4, 2013, and JNES submitted the draft guide to SNRA on the same date. After that NRA called for public comments for the draft version of the assessment guide, the draft version of the assessment guide was partly amended taking posted public comments account, and tornado effect assessment guide was officially released on June 19, 2013. Contents in this paper are as follows, assessment guide for tornado effect on NPPs (Draft version on April 4, 2013), supplementary documents, calculation examples, and future tasks for further improved reliability of tornado effect assessment on NPPs. This draft guide consists of six chapters

Tornado-related fatalities--five states, Southeastern United States, April 25-28, 2011.

Science.gov (United States)

2012-07-20

During April 25-28, 2011, a massive storm system generated 351 tornadoes (including 15 registering 4 or 5 on the Enhanced Fujita [EF] scale*), killing 338 persons in Alabama, Arkansas, Georgia, Mississippi, and Tennessee. This was the third-deadliest tornado event in the United States, surpassing an April 1974 event that resulted in 315 fatalities. This event also was historic because of the record number of fatalities that occurred despite modern advances in tornado forecasting, advanced warning times, and media coverage. Risk factors for death and injury from tornadoes are sheltering in mobile homes, proximity to an EF-4 or EF-5 tornado, being an older adult (aged ≥65 years), lack of accessibility to safe rooms (e.g., basements or reinforced shelters), and a night-time tornado impact. To describe the fatalities by demographic characteristics, type of shelter used, cause of death, and tornado severity and location, CDC reviewed data from the American Red Cross (Red Cross), death certificates, and the National Weather Service (NWS). This report summarizes the results of that review. Among the 338 decedents, median age was 55.0 years (range: 4 days-97 years); approximately one third were older adults. On tornado impact, 46.7% of decedents were in single-family homes, and 26.6% were in mobile homes. The leading cause of death was traumatic injury, including 21.9% with head injuries. Half of the deadly tornadoes were rated EF-4 or EF-5 and were responsible for 89.5% of the deaths. To prevent tornado-related deaths, health messaging should encourage the public (especially older adults and residents of mobile/manufactured homes) to pre-identify an accessible safe room, prepare the room with personal protection items (e.g., blankets and helmets), and monitor local weather.

The occurrence of a tornado in Serbia on 31 march 2013

Directory of Open Access Journals (Sweden)

Pavlovic-Berdon Nada

2013-01-01

Full Text Available Tornado occurs very rarely in the territory of Serbia. The occurrence of a tornado above Torda (Vojvodina, Serbia on 31 March 2013 indicted the importance of monitoring such a dangerous weather phenomenon, knowing its characteristics and forecasting it. This paper analyzes the synoptic conditions and vertical structure of the atmosphere that prevailed during the development of a supercell with a tornado. Changes in temperature and air pressure are presented on mesoscale maps. The analysis was performed by using the Nonhydrostatic Mesoscale Model (NMM. The tornado occurrence was monitored via satellite images and radar characteristics of a supercell. The cause of tornadogenesis has been ascertained. According to the EF scale, the tornado reached F0 intensity. Damages to roofs, power lines, trees and cars caused by the wind (>35ms-1 are also presented.

Teacher Guidelines for Helping Students after a Tornado

Science.gov (United States)

National Child Traumatic Stress Network, 2013

2013-01-01

Being in a tornado can be very frightening, and the days, weeks, and months following the storm can be very stressful. Most families recover over time, especially with the support of relatives, friends, and their community. But different families may have different experiences during and after a tornado, and how long it takes them to recover will…

Tornadoes and waterspouts in Catalonia (1950-2009)

OpenAIRE

Gayà, M.; Llasat Botija, María del Carmen; Arús Dumenjó, Joan

2011-01-01

This paper presents a preliminary climatology of tornadoes and waterspouts in Catalonia (NE Iberian Peninsula). A database spanning 60 yr (1950–2009) has been developed on the basis of information collected from various sources such as weather reports, insurance companies, newspapers and damage surveys. This database has been subjected to a rigorous validation process, and the climatology describes its main features: timing, spatial pattern, and trends in the tornado and wat...

An experimental investigation of wind pressures on square pillars in tornado-like vortices

International Nuclear Information System (INIS)

Iwatani, Yoshiharu; Maruta, Eizou; Kanda, Makoto; Hattori, Yousuke; Hamano, Naoki; Matsuura, Takeshi

1992-01-01

This report describes a laboratory simulation of tornado-like vortices and laboratory measurements of steady wind loads on model structures in tornado-like vortices. The variations of wind direction and wind speed of tornado-like vortices and ground surface pressure under tornado-like vortices with the swirl ratio, Reynolds number and the surface roughness were investigated. Wind pressure distributions on square pillars were measured in tornado-like vortices. It was observed in the experiment that the negative pressures on the roof faces of square pillars were high and distributed rather uniformly but these on the side faces differed greatly from place to place and locally became high. The high pressure regions on the side faces were close to ground surface in the case where the model structures stood in the center of tornado-like vortex, and became higher as the increase of distance between the model structures and the center of tornado-like vortices. (author)

AM05-13-009 Experimental simulation of non-supercell tornadoes

OpenAIRE

佐々, 浩司; Koji, Sassa; 高知大理; Kochi Univ.

2005-01-01

The non-supercell tornadoes was experimentally simulated by the combination of the gust made of dry ice and the updraft fan. Three typical patterns of tornadoes were observed in relation to the change of updraft velocity. These patterns are a laminar vortex, a turbulent vortex and a spiral vortex. The resultant tornadoes were found to move with the updraft fan. They broke down when the moving velocity was larger than the mean velocity in the shear line.

Tornadoes in Canada for the period 1950 to 1979

International Nuclear Information System (INIS)

Newark, M.J.

1981-06-01

This report has attempted to arrive at a set of quantitative conclusions concerning the physical characteristics of tornadoes from what is basically a set of qualitative data. The task was composed of a number of steps: a) finding the data in the first place, b) defining the terms and equations to be used in the study, c) devising a method of dealing with the errors and inconsistencies in the data, d) encoding it into a quantitative form, e) computerizing the encoded data for ease of sorting and calculation, and f) analyzing the result. The results of the study give details concerning the physical dimensions of tornado damage; national maps of tornado incidence and risk; probability of tornado damage in selected cities; diurnal and seasonal frequencies as well as frequencies of travel direction and F-scale number; length of tornado season. An analysis has been made of the distribution of damage length, width and area in order to find whether or not correlations exist among them, and whether or not they can be described in a mathematical fashion. No correlations were found, and although the distributions of these dimensions superficially resembled a log normal curve, this result failed to be statistically significant

Tornadoes and waterspouts in Catalonia (1950–2009

Directory of Open Access Journals (Sweden)

M. Gayà

2011-07-01

Full Text Available This paper presents a preliminary climatology of tornadoes and waterspouts in Catalonia (NE Iberian Peninsula. A database spanning 60 yr (1950–2009 has been developed on the basis of information collected from various sources such as weather reports, insurance companies, newspapers and damage surveys. This database has been subjected to a rigorous validation process, and the climatology describes its main features: timing, spatial pattern, and trends in the tornado and waterspout distribution. Results show the highest concentration of tornadoes from August to October, the highest density in the heavily populated coastal areas and a growing positive trend that is likely more closely linked to an increase in observation and perception rather than a real climatic trend.

The recollective qualities of adolescents' and adults' narratives about a long-ago tornado.

Science.gov (United States)

Bauer, Patricia J; Stark, Emily N; Ackil, Jennifer K; Larkina, Marina; Merrill, Natalie; Fivush, Robyn

2017-03-01

The recollective qualities of autobiographical memory are thought to develop over the course of the first two decades of life. We used a 9-year follow-up test of recall of a devastating tornado and of non-tornado-related events from before and after the storm, to compare the recollective qualities of adolescents' (n = 20, ages 11 years, 11 months to 20 years, 8 months) and adults' (n = 14) autobiographical memories. At the time of the tornado, half of the adolescents had been younger than age 6. Nine years after the event, all participants provided evidence that they recall the event of the tornado. Adults also had high levels of recall of the non-tornado-related events. Adolescents recalled proportionally fewer non-tornado-related events; adolescents younger than 6 at the time of the events recalled the fewest non-tornado-related events. Relative to adolescents, adults produced longer narratives. With narrative length controlled, there were few differences in the recollective qualities of adolescents' and adults' narrative reports, especially in the case of the tornado; the recollective qualities were stronger among adolescents older at the time of the events. Overall, participants in both age groups provided evidence of the qualities of recollection that are characteristic of autobiographical memory.

Assessment of the bases for selecting criteria for protection against tornado-entrained debris

International Nuclear Information System (INIS)

Read, J.B.J.; Bell, L.W.

1977-05-01

The probabilities and consequences of the acceleration of solid objects by air motion within a tornado are discussed, in order to assess the risks of damage from tornado missiles. Design criteria for protection against tornado missile risks are suggested

Wind pressure testing of tornado safe room components made from wood

Science.gov (United States)

Robert Falk; Deepak Shrestha

2016-01-01

To evaluate the ability of a wood tornado safe room to resist wind pressures produced by a tornado, two safe room com-ponents were tested for wind pressure strength. A tornado safe room ceiling panel and door were static-pressure-tested according to ASTM E 330 using a vacuum test system. Re-sults indicate that the panels had load capacities from 2.4 to 3.5 times that...

Full-scale tornado-missile impact tests. Interim report

International Nuclear Information System (INIS)

Stephenson, A.E.

1976-04-01

Seven completed initial tests are described with 4 types of hypothetical tornado-borne missiles (impacting reinforced concrete panels that are typical of walls in nuclear power facilities). The missiles were rocket propelled to velocities currently postulated as being attainable by debris in tornadoes. (1500-pound 35-foot long utility pole; 8-pound 1-inch Grade 60 reinforcing bar; 78-pound 3-inch Schedule 40 pipe; and 743-pound 12-inch Schedule 40 pipe;) The results show that a minimum thickness of 24 inches is sufficient to prevent backface scabbing from normal impacts of currently postulated tornado missiles and that existing power plant walls are adequate for the most severe conditions currently postulated by regulatory agencies. This report gives selected detailed data on the tests completed thus far, including strain, panel velocity, and reaction histories

Residential tornado safe room from commodity wood products – design and development

Science.gov (United States)

Robert H. Falk; James J. Bridwell

2018-01-01

In the United States, tornadoes cause significant damage and result in many injuries and deaths. Although the development and use of tornado safe rooms have helped decrease the human toll associated with these events, the cost of these structures is often too high for many that could benefit from their use. The development of a nonproprietary residential tornado safe...

An experimental investigation of flow around a vehicle passing through a tornado

Science.gov (United States)

Suzuki, Masahiro; Obara, Kouhei; Okura, Nobuyuki

2016-03-01

Flow around a vehicle running through a tornado was investigated experimentally. A tornado simulator was developed to generate a tornado-like swirl flow. PIV study confirmed that the simulator generates two-celled vortices which are observed in the natural tornadoes. A moving test rig was developed to run a 1/40 scaled train-shaped model vehicle under the tornado simulator. The car contained pressure sensors, a data logger with an AD converter to measure unsteady surface pressures during its run through the swirling flow. Aerodynamic forces acting on the vehicle were estimated from the pressure data. The results show that the aerodynamic forces change its magnitude and direction depending on the position of the car in the swirling flow. The asymmetry of the forces about the vortex centre suggests the vehicle itself may deform the flow field.

An experimental investigation of flow around a vehicle passing through a tornado

Directory of Open Access Journals (Sweden)

Suzuki Masahiro

2016-01-01

Full Text Available Flow around a vehicle running through a tornado was investigated experimentally. A tornado simulator was developed to generate a tornado-like swirl flow. PIV study confirmed that the simulator generates two-celled vortices which are observed in the natural tornadoes. A moving test rig was developed to run a 1/40 scaled train-shaped model vehicle under the tornado simulator. The car contained pressure sensors, a data logger with an AD converter to measure unsteady surface pressures during its run through the swirling flow. Aerodynamic forces acting on the vehicle were estimated from the pressure data. The results show that the aerodynamic forces change its magnitude and direction depending on the position of the car in the swirling flow. The asymmetry of the forces about the vortex centre suggests the vehicle itself may deform the flow field.

Numerical simulation of tornado-borne missile impact

International Nuclear Information System (INIS)

Tu, D.K.; Murray, R.C.

1977-01-01

The feasibility of using a finite element procedure to examine the impact phenomenon of a tornado-borne missile impinging on a reinforced concrete barrier was assessed. The major emphasis of this study was to simulate the impact of a nondeformable missile. Several series of simulations were run, using an 8-in.-dia steel slug as the impacting missile. The numerical results were then compared with experimental field tests and empirical formulas. The work is in support of tornado design practices for fuel reprocessing and fuel fabrication plants

DYNAMICS OF A SOLAR PROMINENCE TORNADO OBSERVED BY SDO/AIA ON 2012 NOVEMBER 7–8

Energy Technology Data Exchange (ETDEWEB)

Mghebrishvili, Irakli; Zaqarashvili, Teimuraz V.; Kukhianidze, Vasil; Ramishvili, Giorgi [Abastumani Astrophysical Observatory at Ilia State University, University St. 2, Tbilisi, Georgia (United States); Shergelashvili, Bidzina [Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, A-8042 Graz (Austria); Veronig, Astrid [IGAM-Kanzelhöhe Observatory, Institute of Physics, University of Graz, Universitätsplatz 5, A-8010 Graz (Austria); Poedts, Stefaan, E-mail: teimuraz.zaqarashvili@oeaw.ac.at [Centre for Mathematical Plasma Astrophysics, Celestijnenlaan 200B, B-3001 Leuven (Belgium)

2015-09-10

We study the detailed dynamics of a solar prominence tornado using time series of 171, 304, 193, and 211 Å spectral lines obtained by the Solar Dynamics Observatory/Atmospheric Imaging Assembly during 2012 November 7–8. The tornado first appeared at 08:00 UT, November 07, near the surface, gradually rose upwards with the mean speed of ∼1.5 km s{sup −1} and persisted over 30 hr. Time–distance plots show two patterns of quasi-periodic transverse displacements of the tornado axis with periods of 40 and 50 minutes at different phases of the tornado evolution. The first pattern occurred during the rising phase and can be explained by the upward motion of the twisted tornado. The second pattern occurred during the later stage of evolution when the tornado already stopped rising and could be caused either by MHD kink waves in the tornado or by the rotation of two tornado threads around a common axis. The later hypothesis is supported by the fact that the tornado sometimes showed a double structure during the quasi-periodic phase. 211 and 193 Å spectral lines show a coronal cavity above the prominence/tornado, which started expansion at ∼13:00 UT and continuously rose above the solar limb. The tornado finally became unstable and erupted together with the corresponding prominence as coronal mass ejection (CME) at 15:00 UT, November 08. The final stage of the evolution of the cavity and the tornado-related prominence resembles the magnetic breakout model. On the other hand, the kink instability may destabilize the twisted tornado, and consequently prominence tornadoes can be used as precursors for CMEs.

Tornado Protection: Selecting and Designing Safe Areas in Buildings.

Science.gov (United States)

Abernethy, James J.

Tornadoes and extreme winds cause heavy loss of life and property damage throughout the United States. Most buildings offer significant protection from this danger, and building administrators should know the areas where this protection is available. This booklet presents a review of three schools, all of which were struck by tornadoes on April 3,…

Doppler Radar and Lightning Network Observations of a Severe Outbreak of Tropical Cyclone Tornadoes

Science.gov (United States)

Mccaul, Eugene W., Jr.; Buechler, Dennis E.; Goodman, Steven J.; Cammarata, Michael

2004-01-01

Data from a single Weather Surveillance Radar-1988 Doppler (WSR-88D) and the National Lightning Detection Network are used to examine the characteristics of the convective storms that produced a severe tornado outbreak, including three tornadoes that reached F3 intensity, within Tropical Storm Beryl s remnants on 16 August 1994. Comparison of the radar data with reports of tornadoes suggests that only 13 cells produced the 29 tornadoes that were documented in Georgia and the Carolinas on that date. Six of these cells spawned multiple tornadoes, and the radar data confirm the presence of miniature supercells. One of the cells was identifiable on radar for 11 h. spawning tornadoes over a time period spanning approximately 6.5 h. Several other tornadic cells also exhibited great longevity, with cell lifetimes longer than ever previously documented in a landfalling tropical cyclone (TC) tornado event. This event is easily the most intense TC tornado outbreak yet documented with WSR-88Ds. Time-height analyses of the three strongest tornadic supercells are presented in order to document storm kinematic structure and to show how these storms appear at different ranges from a WSR-88D. In addition, cloud-to-ground (CG) lightning data are examined in Beryl s remnants. Although the tornadic cells were responsible for most of Beryl's CG lightning, their flash rates were only weak to moderate, and in all the tornadic storms the lightning flashes were almost entirely negative in polarity. A few of the single-tornado storms produced no detectable CG lightning at all. There is evidence that CG lightning rates decreased during the tornadoes, compared to 30-min periods before the tornadoes. A number of the storms spawned tornadoes just after producing their final CG lightning flashes. Contrary to the findings for flash rates, both peak currents and positive flash percentages were larger in Beryl's nontornadic storms than in the tornadic ones.

Comprehensive analysis of tornado statistics in comparison to earthquakes: intensity and temporal behaviour

Directory of Open Access Journals (Sweden)

L. Schielicke

2013-01-01

Full Text Available Tornadoes and earthquakes are characterised by a high variability in their properties concerning intensity, geometric properties and temporal behaviour. Earthquakes are known for power-law behaviour in their intensity (Gutenberg–Richter law and temporal statistics (e.g. Omori law and interevent waiting times. The observed similarity of high variability of these two phenomena motivated us to compare the statistical behaviour of tornadoes using seismological methods and quest for power-law behaviour. In general, the statistics of tornadoes show power-law behaviour partly coextensive with characteristic scales when the temporal resolution is high (10 to 60 min. These characteristic scales match with the typical diurnal behaviour of tornadoes, which is characterised by a maximum of tornado occurrences in the late afternoon hours. Furthermore, the distributions support the observation that tornadoes cluster in time. Finally, we shortly discuss a possible similar underlying structure composed of heterogeneous, coupled, interactive threshold oscillators that possibly explains the observed behaviour.

Spatial Distributions of Tropical Cyclone Tornadoes by Intensity and Size Characteristics

OpenAIRE

Todd W. Moore; Nicholas J. Sokol; Robert A. Blume

2017-01-01

Tropical cyclones that make landfall often spawn tornadoes. Previous studies have shown that these tornadoes are not uniformly distributed in the United States or in the tropical cyclone environment. They show that tornadoes tend to occur relatively close to the coastline and that they tend to cluster to the east-of-center in the tropical cyclone environment, particularly in the northeast and east-of-center quadrants. This study contributes to these studies by analyzing the spatial distributi...

Latest climate changes in Romania :tornadoes

Science.gov (United States)

Pop, Elena

2014-05-01

Latest climate changes in Romania :tornadoes As climate change has been considered a research priority in the European Strategy for enduring development , I have done a detailed research with my students of the new climate change that has been going on in Romania for the past decade. More precisely I have studied together with my students the phenomenon of tornadoes that have seriously affected on some occasions some our our country's locations, such as Facaeni, in the county of Ialomita, in August 2002. A quite unusual phenomenon occurred on that location situated at 44.56 degrees northern latitude and at 27.89 degrees eastern longitude, that caused severe damage to the local environment and three persons lost their lives in the process, as well as other thirty people suffering from bad injuries. The magnitude of that strong phenomenon rose on the Fujita scale at level F3 which implied wing gusts between 252-300 km/ hour . A main cause of occurrence of such a severe weather was the difference in temperature of two huge air masses, one of Polar origin, and other coming from tropical latitudes . Their crossroads was on that precise territory of Romania. The duration of the worst part of the tornado path lasted only for two minutes, but the consequences of its passage were colossal : total destruction of 33 households, and other 395 were partially damaged, 1,000 people afflicted by the devastation and 100 acres of acacia tree forest ripped off the ground. The first ever recorded tornado phenomenon in Romania was around 1894-1896, considered at that time " a freak of nature" was seen as a cloud formation abnormality , an uncontrolled force of nature that had a huge impact , and at the same time, it vanished into "thin air " fast. The most affected areas in Romania by tornadoes are the south-eastern planes where the cloud formations can create fast columns of air rotating up to 500 km/hour. The local people compared the cloud funnels created on the planes to "serpents

Apophysomyces trapeziformis infection associated with a tornado-related injury.

Science.gov (United States)

Weddle, Gina; Gandy, Kimberly; Bratcher, Denise; Pahud, Barbara; Jackson, Mary Anne

2012-06-01

This report defines the role of Apophysomyces as an aggressive fungal pathogen seen after a tornado injury. Clinical and laboratory manifestations of infections after environmentally contaminated wounds incurred during a tornado are outlined, emphasizing mechanism of injury, comorbidities, and diagnostic and treatment challenges. Therapy with systemic antifungal therapy and aggressive serial tissue debridement was successful in achieving cure.

An evaluation method for tornado missile strike probability with stochastic correction

Energy Technology Data Exchange (ETDEWEB)

Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo [Nuclear Risk Research Center (External Natural Event Research Team), Central Research Institute of Electric Power Industry, Abiko (Japan)

2017-03-15

An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure.

An evaluation method for tornado missile strike probability with stochastic correction

International Nuclear Information System (INIS)

Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo

2017-01-01

An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure

Prepare to protect: Operating and maintaining a tornado safe room.

Science.gov (United States)

Herseth, Andrew; Goldsmith-Grinspoon, Jennifer; Scott, Pataya

2017-06-01

Operating and maintaining a tornado safe room can be critical to the effective continuity of business operations because a firm's most valuable asset is its people. This paper describes aspects of operations and maintenance (O&M) for existing tornado safe rooms as well as a few planning and design aspects that affect the ultimate operation of a safe room for situations where a safe room is planned, but not yet constructed. The information is based on several Federal Emergency Management Agency safe room publications that provide guidance on emergency management and operations, as well as the design and construction of tornado safe rooms.

Millimeter-wave molecular line observations of the Tornado nebula

International Nuclear Information System (INIS)

Sakai, D.; Oka, T.; Tanaka, K.; Matsumura, S.; Miura, K.; Takekawa, S.

2014-01-01

We report the results of millimeter-wave molecular line observations of the Tornado Nebula (G357.7-0.1), which is a bright radio source behind the Galactic center region. A 15' × 15' area was mapped in the J = 1-0 lines of CO, 13 CO, and HCO + with the Nobeyama Radio Observatory 45 m telescope. The Very Large Array archival data of OH at 1720 MHz were also reanalyzed. We found two molecular clouds with separate velocities, V LSR = –14 km s –1 and +5 km s –1 . These clouds show rough spatial anti-correlation. Both clouds are associated with OH 1720 MHz emissions in the area overlapping with the Tornado Nebula. The spatial and velocity coincidence indicates violent interaction between the clouds and the Tornado Nebula. Modestly excited gas prefers the position of the Tornado 'head' in the –14 km s –1 cloud, also suggesting the interaction. Virial analysis shows that the +5 km s –1 cloud is more tightly bound by self-gravity than the –14 km s –1 cloud. We propose a formation scenario for the Tornado Nebula; the +5 km s –1 cloud collided into the –14 km s –1 cloud, generating a high-density layer behind the shock front, which activates a putative compact object by Bondi-Hoyle-Lyttleton accretion to eject a pair of bipolar jets.

Annual and seasonal tornado activity in the United States and the global wind oscillation

Science.gov (United States)

Moore, Todd W.

2018-06-01

Previous studies have searched for relationships between tornado activity and atmospheric teleconnections to provide insight on the relationship between tornadoes, their environments, and larger scale patterns in the climate system. Knowledge of these relationships is practical because it can improve seasonal and sub-seasonal predictions of tornado probability and, therefore, help mitigate tornado-related losses. This study explores the relationships between the annual and seasonal tornado activity in the United States and the Global Wind Oscillation. Time series herein show that phases of the Global Wind Oscillation, and atmospheric angular momentum anomalies, vary over a period of roughly 20-25 years. Rank correlations indicate that tornado activity is weakly correlated with phases 2, 3, and 4 (positive) and 6, 7, and 8 (negative) of the Global Wind Oscillation in winter, spring, and fall. The correlation is not as clear in summer or at the annual scale. Non-parametric Mann-Whitney U tests indicate that winters and springs with more phase 2, 3, and 4 and fewer phase 6, 7, and 8 days tend to have more tornadoes. Lastly, logistic regression models indicate that winters and springs with more phase 2, 3, and 4 days have greater likelihoods of having more than normal tornado activity. Combined, these analyses suggest that seasons with more low atmospheric angular momentum days, or phase 2, 3, and 4 days, tend to have greater tornado activity than those with fewer days, and that this relationship is most evident in winter and spring.

Annual and seasonal tornado activity in the United States and the global wind oscillation

Science.gov (United States)

Moore, Todd W.

2017-08-01

Previous studies have searched for relationships between tornado activity and atmospheric teleconnections to provide insight on the relationship between tornadoes, their environments, and larger scale patterns in the climate system. Knowledge of these relationships is practical because it can improve seasonal and sub-seasonal predictions of tornado probability and, therefore, help mitigate tornado-related losses. This study explores the relationships between the annual and seasonal tornado activity in the United States and the Global Wind Oscillation. Time series herein show that phases of the Global Wind Oscillation, and atmospheric angular momentum anomalies, vary over a period of roughly 20-25 years. Rank correlations indicate that tornado activity is weakly correlated with phases 2, 3, and 4 (positive) and 6, 7, and 8 (negative) of the Global Wind Oscillation in winter, spring, and fall. The correlation is not as clear in summer or at the annual scale. Non-parametric Mann-Whitney U tests indicate that winters and springs with more phase 2, 3, and 4 and fewer phase 6, 7, and 8 days tend to have more tornadoes. Lastly, logistic regression models indicate that winters and springs with more phase 2, 3, and 4 days have greater likelihoods of having more than normal tornado activity. Combined, these analyses suggest that seasons with more low atmospheric angular momentum days, or phase 2, 3, and 4 days, tend to have greater tornado activity than those with fewer days, and that this relationship is most evident in winter and spring.

Tornado frequency in the USA - meteorological and non-meteorological factors of a downward trend

Directory of Open Access Journals (Sweden)

Mihajlović Jovan

2015-01-01

Full Text Available Citing numerical simulations, climate alarmists believe that global warming will lead to more frequent and more intensive tornadoes. Considering temperature increase data in the contiguous USA, this study has investigated the trend of strong tornadoes in F3+ category in the 1954-2012 period. Statistically significant decrease of tornadoes per year at an average rate of 0.44 has been recorded, that is, 4.4 tornadoes per decade. Tornado increase has been recorded with F0 and F1 categories and the cause of this increase lies in meteorological and non-meteorological factors. By using upper and lower standard deviation values, the stages of tornado activity have been singled out. The 1957-1974 period may be considered as an active stage and the 1978-2009 period as an inactive stage. Upward trend of air temperature increase does not correspond with the downward trend of the number of F3+ tornado category, while the correlation coefficient between these two variables is R = −0.14. This fact does not correspond with the simulation results and output data of various numerical models anticipating an increase in the number and intensity of tornado events in the conditions of surface air temperature growth.

ASSESSMENT OF TORNADOS WITH THE ENHANCED FUJITA SCALE IN ROMANIA

Directory of Open Access Journals (Sweden)

C. NUCUŢĂ

2011-03-01

Full Text Available Assessment of tornadoes with the Enhanced Fujita Scale in Romania. An analysis of the damage caused by a tornado, in order to determine the maximum wind speed that was reached, is important both in terms of documenting the phenomenon and to make improvements to the evaluation method which is used, especially if this method is not specific for the analyzed territory. An overview of the way the tornado from Silivaşu de Câmpie, on the 26th of May 2010, was termed EF2 is done to summarize the difficulties that arise in the assessment of tornadoes occurring in Romania with the Enhanced Fujita scale. The lack of correlation between damage indicators, different construction styles and building materials between those in the United States and those selected in this case study are the main issues addressed. Solutions for these issues are discussed as a starting point for the adjustment of Enhanced Fujita scale for Romania.

Schools in Kansas with Tornado Protection. Shawnee Mission Public Schools--District No. 512.

Science.gov (United States)

Ward, Delbert B.

Kansas and nearby Missouri are among the half-dozen states in America having the greatest frequency of tornadoes of any region in the world. This booklet describes a districtwide approach of designing and constructing tornado-resistant shelters as integrated parts of the school facilities. The design criteria for tornado protection also resulted…

Differential pressures on building walls during tornados

International Nuclear Information System (INIS)

Yeh, G.C.K.

1975-01-01

In the United States, containment structures and some auxiliary structures (control building, auxiliary building, spent fuel building, etc.) in nuclear power plants are required to be designed to withstand the effects of the design basis tornado. In addition to velocity pressures and missile impact a tornado also gives rise to a rapid change in atmospheric pressure, which can, in cases of closed or partially vented structures, produce direct differential pressure loading. In this paper a digital computer program is described which applies a tornado-induced, time-dependent atmospheric pressure change to a building and calculates the differential pressure histories across the interior and exterior walls of the building. Laws for quasi-steady, one-dimensional motion of an ideal compressible gas are used to calculate the pressures due to the flow of air through ports, doors and windows in the building. Numerical examples show that for each assumed atmospheric pressure change history a vent area to compartment volume ratio may be specified as the criterion for a building to be considered fully vented. (orig.) [de

Tornado missile simulation and risk analysis

International Nuclear Information System (INIS)

Twisdale, L.A.; Dunn, W.L.; Chu, J.

1978-01-01

Mathematical models of the contributing events to the tornado missile hazard at nuclear power plants have been developed in which the major sources of uncertainty have been considered in a probabilistic framework. These models have been structured into a sequential event formalism which permits the treatment of both single and multiple missile generation events. A simulation computer code utilizing these models has been developed to obtain estimates of tornado missile event likelihoods. Two case studies have been analyzed; the results indicate that the probability of a single missile from the sampling population impacting any of the plant's targets is less then about 10 -7 per reactor-year. Additional work is needed for verification and sensitivity study

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity.

Science.gov (United States)

Tippett, Michael K; Cohen, Joel E

2016-02-29

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from 'outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

Science.gov (United States)

Tippett, Michael K.; Cohen, Joel E.

2016-01-01

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from ‘outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954–2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related. PMID:26923210

The February 21, 1993 tornadoes of East Tennessee

Energy Technology Data Exchange (ETDEWEB)

Fricke, K.E.; Kornegay, F.C. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1993-08-11

A series of tornadoes struck the east Tennessee area on Sunday afternoon, February 21, 1993 around Knoxville, Lenoir City, and Oak Ridge causing millions of dollars worth of damage to both homes and businesses in the area, killing one, injuring a number of persons, and leaving a large area without power for many hours or even days due to damage to the local TVA transmission line network. One tornado touched down in the Department of Energy Oak Ridge Reservation near the Oak Ridge Y-12 Plant, continued through the Union Valley business district located just east of the plant, through the adjacent University of Tennessee Arboretum and then continued into the communities of Claxton and Powell. The path length of the tornado was approximately 13 miles. Damage to the Y-12 Plant was minimal, but the Union Valley business district was seriously damaged, including the Fusion Energy Design Center (FEDC) which houses a number of DOE related projects. The preliminary cost estimate of the damage to DOE facilities (both at Y-12 and at the FEDC) was around $520,000. This paper describes the local meteorological data, the tornado that struck near the Y-12 plant, the resulting damage both to the DOE facilities and to the surrounding communities, the plant emergency response and recovery activities, and the current hazard analyses being undertaken at the plant.

Two-phase flows in the formed tornado funnel

Science.gov (United States)

Sinkevich, O. A.; Bortsova, A. A.

2017-10-01

At present, it is obvious that the problem of the tornado is important not only for our planetЮ to determine the conditions for the formation of a tornado, it is required to take into account a number of hydrodynamic and plasma processes [1 - 6]. Along to prediction of a tornado generation conditions [1 - 3] it is necessary to evaluate the characteristics of its quasi-stationary motion in a formed funnel: the mass of the moving moist air involved in the funnel and the size and form of the funnel. For a complete description of the phenomena, it is necessary to involve numerical calculations. We note that even for numerical calculations using powerful computers, the problem is very difficult because of the need to calculate multiphase turbulent flows with free, self-organizing boundaries [1, 6]. However, “strict” numerical calculations, it is impossible to do without the use of many, often mutually exclusive, models. For example, how to choice an adequate model of turbulence (algebraic, k-ε model, etc.) or the use of additional, often not accepted, hypotheses about certain processes used in calculations (mechanisms on the nature of moisture condensation, etc.). Therefore, along with numerical calculations of such flows, modeling problems that allow an exact solution and allow to determine the most important and observed characteristics of a tornado.

Why do tornados and hailstorms rest on weekends?

Science.gov (United States)

Rosenfeld, Daniel; Bell, Thomas L.

2011-10-01

This study shows for the first time statistical evidence that when anthropogenic aerosols over the eastern United States during summertime are at their weekly mid-week peak, tornado and hailstorm activity there is also near its weekly maximum. The weekly cycle in summertime storm activity for 1995-2009 was found to be statistically significant and unlikely to be due to natural variability. It correlates well with previously observed weekly cycles of other measures of storm activity. The pattern of variability supports the hypothesis that air pollution aerosols invigorate deep convective clouds in a moist, unstable atmosphere, to the extent of inducing production of large hailstones and tornados. This is caused by the effect of aerosols on cloud drop nucleation, making cloud drops smaller and hydrometeors larger. According to simulations, the larger ice hydrometeors contribute to more hail. The reduced evaporation from the larger hydrometeors produces weaker cold pools. Simulations have shown that too cold and fast-expanding pools inhibit the formation of tornados. The statistical observations suggest that this might be the mechanism by which the weekly modulation in pollution aerosols is causing the weekly cycle in severe convective storms during summer over the eastern United States. Although we focus here on the role of aerosols, they are not a primary atmospheric driver of tornados and hailstorms but rather modulate them in certain conditions.

The February 21, 1993 tornadoes of East Tennessee

International Nuclear Information System (INIS)

Fricke, K.E.; Kornegay, F.C.

1993-01-01

A series of tornadoes struck the east Tennessee area on Sunday afternoon, February 21, 1993 around Knoxville, Lenoir City, and Oak Ridge causing millions of dollars worth of damage to both homes and businesses in the area, killing one, injuring a number of persons, and leaving a large area without power for many hours or even days due to damage to the local TVA transmission line network. One tornado touched down in the Department of Energy Oak Ridge Reservation near the Oak Ridge Y-12 Plant, continued through the Union Valley business district located just east of the plant, through the adjacent University of Tennessee Arboretum and then continued into the communities of Claxton and Powell. The path length of the tornado was approximately 13 miles. Damage to the Y-12 Plant was minimal, but the Union Valley business district was seriously damaged, including the Fusion Energy Design Center (FEDC) which houses a number of DOE related projects. The preliminary cost estimate of the damage to DOE facilities (both at Y-12 and at the FEDC) was around $520,000. This paper describes the local meteorological data, the tornado that struck near the Y-12 plant, the resulting damage both to the DOE facilities and to the surrounding communities, the plant emergency response and recovery activities, and the current hazard analyses being undertaken at the plant

Millimeter-wave molecular line observations of the Tornado nebula

Energy Technology Data Exchange (ETDEWEB)

Sakai, D. [Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Oka, T.; Tanaka, K.; Matsumura, S.; Miura, K.; Takekawa, S., E-mail: sakai.daisuke@nao.ac.jp [Department of Physics, Institute of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan)

2014-08-10

We report the results of millimeter-wave molecular line observations of the Tornado Nebula (G357.7-0.1), which is a bright radio source behind the Galactic center region. A 15' × 15' area was mapped in the J = 1-0 lines of CO, {sup 13}CO, and HCO{sup +} with the Nobeyama Radio Observatory 45 m telescope. The Very Large Array archival data of OH at 1720 MHz were also reanalyzed. We found two molecular clouds with separate velocities, V{sub LSR} = –14 km s{sup –1} and +5 km s{sup –1}. These clouds show rough spatial anti-correlation. Both clouds are associated with OH 1720 MHz emissions in the area overlapping with the Tornado Nebula. The spatial and velocity coincidence indicates violent interaction between the clouds and the Tornado Nebula. Modestly excited gas prefers the position of the Tornado 'head' in the –14 km s{sup –1} cloud, also suggesting the interaction. Virial analysis shows that the +5 km s{sup –1} cloud is more tightly bound by self-gravity than the –14 km s{sup –1} cloud. We propose a formation scenario for the Tornado Nebula; the +5 km s{sup –1} cloud collided into the –14 km s{sup –1} cloud, generating a high-density layer behind the shock front, which activates a putative compact object by Bondi-Hoyle-Lyttleton accretion to eject a pair of bipolar jets.

Pre-Post Tornado Effects on Aggressive Children's Psychological and Behavioral Adjustment Through One-Year Postdisaster.

Science.gov (United States)

Lochman, John E; Vernberg, Eric; Powell, Nicole P; Boxmeyer, Caroline L; Jarrett, Matthew; McDonald, Kristina; Qu, Lixin; Hendrickson, Michelle; Kassing, Francesca

2017-01-01

Using a risk-resilience framework, this study examined how varying levels of exposure to a natural disaster (EF-4 tornado) and children's characteristics (sex; anxiety) influenced the behavioral and psychological adjustment of children who shared a common risk factor predisaster (elevated aggression) prior to exposure through 1-year postdisaster. Participants included 360 children in Grades 4-6 (65% male; 78% African American) and their parents from predominantly low-income households who were already participating in a longitudinal study of indicated prevention effects for externalizing outcomes when the tornado occurred in 2011. Fourth-grade children who were screened for overt aggressive behavior were recruited in 3 annual cohorts (120 per year, beginning in 2009). Parent-rated aggression and internalizing problems were assessed prior to the tornado (Wave 1), within a half-year after the tornado (Wave 2), and at a 1-year follow-up (Wave 3). Children and parents rated their exposure to aspects of tornado-related traumatic experiences at Wave 3. Children displayed less reduction on aggression and internalizing problems if the children had experienced distress after the tornado or fears for their life, in combination with their pre-tornado level of anxiety. Higher levels of children's and parents' exposure to the tornado interacted with children's lower baseline child anxiety to predict less reduction in aggression and internalizing problems 1 year after the tornado. Higher levels of disaster exposure negatively affected at-risk children's level of improvement in aggression and internalizing problems, when life threat (parent- and child-reported) and child-reported distress after the tornado were moderated by baseline anxiety.

Meteorological and engineering approach to the regionalization of tornado wind criteria for nuclear power plant design

International Nuclear Information System (INIS)

1975-01-01

Data on general meteorological factors governing tornado frequency and intensity in various locations throughout the USA are revised. A climatological model of multiple outbreak and long track tornadoes and the relation between the speed of a hurricane and the frequency of tornado occurrence over land and sea are discussed. Data from a structural engineering assessment of tornado damage are summarized and applications of the data for the development of design criteria for buildings and nuclear power plants to minimize tornado damage are suggested. It was concluded that it is very difficult to predict tornado risk and alternate methods and areas of study are presented for consideration

Tornadoes and Other Big Winds.

Science.gov (United States)

Markle, Sandra

1983-01-01

Information is presented for teaching about the formation of tornadoes and their effects. Ideas for relevant class discussion topics, writing assignments, and experiments to illustrate how temperature and air pressure changes involved in the storms work are also given. (PP)

Supercell and tornado roles

Science.gov (United States)

as a consequence of the up- and down-motions. This also was considered a central idea by Lemon and herein. The definition of a tornado has been problematic (as discussed at some length here) but the basic definition of a vortex is problematic (Lugt 1979). The source of difficulty with defining a vortex is the

Exploring the Experiences of Special Educators Following the Joplin Tornado

Science.gov (United States)

Palmer, Allyson

2013-01-01

On May 22, 2011, an EF5 tornado ripped through Joplin, MO, leaving many residents without homes and destroying or damaging several school buildings. The purpose of this qualitative study was to explore how special education teachers responded to the needs of their students with disabilities following the Joplin tornado. Purposeful sampling was…

Residential Tornado Safe Rooms from Commodity Wood Products: Wall Development and Impact Testing

Science.gov (United States)

Robert H. Falk; James J. Bridwell; John C. Hermanson

2015-01-01

In the United States, tornadoes cause significant damage and result in many injuries and deaths. Although the development and use of tornado safe rooms and shelters have helped reduce the human toll associated with these events, the cost of these structures is often too high for many that could benefit from their use. The development of a residential tornado safe room...

Near-ground tornado-like vortex structure resolved by particle image velocimetry (PIV)

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wei [Iowa State University, Aerospace Engineering Department, Ames, IA (United States); University of Minnesota, Saint Anthony Falls Laboratory, Minneapolis, MN (United States); Sarkar, Partha P. [Iowa State University, Aerospace Engineering Department, Ames, IA (United States)

2012-02-15

The near-ground flow structure of tornadoes is of utmost interest because it determines how and to what extent civil structures could get damaged in tornado events. We simulated tornado-like vortex flow at the swirl ratios of S = 0.03-0.3 (vane angle {theta}{sub v} = 15 -60 ), using a laboratory tornado simulator and investigated the near-ground-vortex structure by particle imaging velocimetry. Complicated near-ground flow was measured in two orthogonal views: horizontal planes at various elevations (z = 11, 26 and 53 mm above the ground) and the meridian plane. We observed two distinct vortex structures: a single-celled vortex at the lowest swirl ratio (S = 0.03, {theta}{sub v} = 15 ) and multiple suction vortices rotating around the primary vortex (two-celled vortex) at higher swirl ratios (S = 0.1-0.3, {theta}{sub v} = 30 -60 ). We quantified the effects of vortex wandering on the mean flow and found that vortex wandering was important and should be taken into account in the low swirl ratio case. The tangential velocity, as the dominant velocity component, has the peak value about three times that of the maximum radial velocity regardless of the swirl ratio. The maximum velocity variance is about twice at the high swirl ratio ({theta}{sub v} = 45 ) that at the low swirl ratio ({theta}{sub v} = 15 ), which is contributed significantly by the multiple small-scale secondary vortices. Here, the results show that not only the intensified mean flow but greatly enhanced turbulence occurs near the surface in the tornado-like vortex flow. The intensified mean flow and enhanced turbulence at the ground level, correlated with the ground-vortex interaction, may cause dramatic damage of the civil structures in tornadoes. This work provides detailed characterization of the tornado-like vortex structure, which has not been fully revealed in previous field studies and laboratory simulations. It would be helpful in improving the understanding of the interaction between the

Conceptions of Tornado Wind Speed and Land Surface Interactions among Undergraduate Students in Nebraska

Science.gov (United States)

Van Den Broeke, Matthew S.; Arthurs, Leilani

2015-01-01

To ascertain novice conceptions of tornado wind speed and the influence of surface characteristics on tornado occurrence, 613 undergraduate students enrolled in introductory science courses at a large state university in Nebraska were surveyed. Our findings show that students lack understanding of the fundamental concepts that (1) tornadoes are…

Systematic Study of the Failure of a Light-Frame Wood Roof in a Tornado

Directory of Open Access Journals (Sweden)

Christine Standohar-Alfano

2012-12-01

Full Text Available Tornadoes are a particularly devastating natural hazard that affect communities across the United States, particularly the Midwest and South. They are unique from an engineering point-of-view due to their very low probability of occurrence but often highly destructive consequences. The 2011 season was particularly devastating to the Southeastern portion of the U.S. This paper presents a single case study of a 2012 tornado that struck a single large rural light-frame wood house with an unconventional roof system. A fragility methodology was used as a tool to probabilistically study the loss of the roof system, and bound an Enhanced Fujita (EF scale rating of the tornado. The tornado was initially rated as an EF3 tornado by the U.S. National Weather Service. However, following a detailed site inspection verified with numerical structural models, the tornado was downgraded to an EF2 tornado. As expected, the use of nail connections in a roof-to-wall connection resulted in a weaker link compared to a hurricane clip. The approach presented in this paper can be used as a supplement to the EF rating provided by U.S. National Weather Service meteorologists when unusual conditions in either the structure or surroundings exists.

Community emergency department utilization following a natural disaster (the Goderich Tornado).

Science.gov (United States)

Appavoo, Samuel D; Khemlin, Alexander; Appavoo, Donna M; Flynn, Candi J

2016-01-01

On 21 August 2011 an F3 tornado hit the Canadian town of Goderich, Ontario, leaving 40 people injured and one dead. Specific medium-term changes in utilization of health care following a disaster have not been analyzed in medical literature. Documenting the emergency department utilization through this subacute period would be helpful to enable institutions and healthcare practitioners to be better prepared for future events. A medical chart review was conducted at the Alexandra Marine and General Hospital in Goderich. All emergency department visits made during the 30 days after the Tornado in 2011 (intervention group), 30 days prior to the tornado in 2011 (primary control group), and during the similar calendar period of 30 days after the tornado in 2010 (seasonal control group) were reviewed. Medical diagnoses of all patients who presented at the emergency department were collected and compared. Fewer people presented to the emergency department following the tornado than during the control periods, and those who did were significantly older than those who presented in the control periods (pptornado in a rural Ontario community. This information serves to inform the medical community and other hospitals how to increase their level of preparedness should a comparable disaster occur again in the future.

Prominence and tornado dynamics observed with IRIS and THEMIS

Science.gov (United States)

Schmieder, Brigitte; Levens, Peter; Labrosse, Nicolas; Mein, Pierre; Lopez Ariste, Arturo; Zapior, Maciek

2017-08-01

Several prominences were observed during campaigns in September 2013 and July 2014 with the IRIS spectrometer and the vector magnetograph THEMIS (Tenerife). SDO/AIA and IRIS provided images and spectra of prominences and tornadoes corresponding to different physical conditions of the transition region between the cool plasma and the corona. The vector magnetic field was derived from THEMIS observations by using the He D3 depolarisation due to the magnetic field. The inversion code (PCA) takes into account the Hanle and Zeeman effects and allows us to compute the strength and the inclination of the magnetic field which is shown to be mostly horizontal in prominences as well as in tornadoes. Movies from SDO/AIA in 304 A and Hinode/SOT in Ca II show the highly dynamic nature of the fine structures. From spectra in Mg II and Si IV lines provided by IRIS and H-alpha observed by the Multi-channel Subtractive Double Pass (MSDP) spectrograph in the Meudon Solar Tower we derived the Doppler shifts of the fine structures and reconstructed the 3D structure of tornadoes. We conclude that the apparent rotation of AIA tornadoes is due to large-scale quasi-periodic oscillations of the plasma along more or less horizontal magnetic structures.

Finite Element Analysis of Saferooms Subjected to Tornado Impact Loads

Science.gov (United States)

Parfilko, Y.; Amaral de Arruda, F.; Varela, B.

2017-10-01

A Tornado is one of the most dreadful and unpredictable events in nature. Unfortunately, weather and geographic conditions make a large portion of the United States prone to this phenomenon. Tornado saferooms are monolithic reinforced concrete protective structures engineered to guard against these natural disasters. Saferooms must withstand impacts and wind loads from EF-5 tornadoes - where the wind speed reaches up to 150 m/s (300 mph) and airborne projectiles can reach up to 50 m/s (100 mph). The objective of this work is to evaluate the performance of a saferoom under impact from tornado-generated debris and tornado-dragged vehicles. Numerical simulations were performed to model the impact problem using explicit dynamics and energy methods. Finite element models of the saferoom, windborne debris, and vehicle models were studied using the LS-DYNA software. RHT concrete material was used to model the saferoom and vehicle models from NCAC were used to characterize damage from impacts at various speeds. Simulation results indicate good performance of the saferoom structure at vehicle impact speeds up to 25 meters per second. Damage is more significant and increases nonlinearly starting at impact velocities of 35 m/s (78 mph). Results of this study give valuable insight into the dynamic response of saferooms subjected to projectile impacts, and provide design considerations for civilian protective structures. Further work is being done to validate the models with experimental measurements.

Characteristics of Tornado-Like Vortices Simulated in a Large-Scale Ward-Type Simulator

Science.gov (United States)

Tang, Zhuo; Feng, Changda; Wu, Liang; Zuo, Delong; James, Darryl L.

2018-02-01

Tornado-like vortices are simulated in a large-scale Ward-type simulator to further advance the understanding of such flows, and to facilitate future studies of tornado wind loading on structures. Measurements of the velocity fields near the simulator floor and the resulting floor surface pressures are interpreted to reveal the mean and fluctuating characteristics of the flow as well as the characteristics of the static-pressure deficit. We focus on the manner in which the swirl ratio and the radial Reynolds number affect these characteristics. The transition of the tornado-like flow from a single-celled vortex to a dual-celled vortex with increasing swirl ratio and the impact of this transition on the flow field and the surface-pressure deficit are closely examined. The mean characteristics of the surface-pressure deficit caused by tornado-like vortices simulated at a number of swirl ratios compare well with the corresponding characteristics recorded during full-scale tornadoes.

Windfield and trajectory models for tornado-propelled objects. Final report

International Nuclear Information System (INIS)

Redmann, G.H.; Radbill, J.R.; Marte, J.E.; Dergarabedian, P.; Fendell, F.E.

1983-03-01

This is the final report of a three-phased research project to develop a six-degree-of-freedom mathematical model to predict the trajectories of tornado-propelled objects. The model is based on the meteorological, aerodynamic, and dynamic processes that govern the trajectories of missiles in a tornadic windfield. The aerodynamic coefficients for the postulated missiles were obtained from full-scale wind tunnel tests on a 12-inch pipe and car and from drop tests. Rocket sled tests were run whereby the 12-inch pipe and car were injected into a worst-case tornado windfield in order to verify the trajectory model. To simplify and facilitate the use of the trajectory model for design applications without having to run the computer program, this report gives the trajectory data for NRC-postulated missiles in tables based on given variables of initial conditions of injection and tornado windfield. Complete descriptions of the tornado windfield and trajectory models are presented. The trajectory model computer program is also included for those desiring to perform trajectory or sensitivity analyses beyond those included in the report or for those wishing to examine other missiles and use other variables

Meteorological environment of a tornado outbreak in Southern Romania

Directory of Open Access Journals (Sweden)

I. C. Oprea

2009-04-01

Full Text Available On 7 May 2005, a squall line with an embedded bow echo formed over Southern Romania causing severe wind damage. The length of the wind damage was around 150 km. Three tornadoes have been reported, two of them being recorded by video camera. One of the tornadoes occurred in Buftea (near Bucharest, the second in Ciobanu village (near Medgidia radar site and the third in Movilita village, 40 km to the northeast of Bucharest. The site surveys confirmed wind damage associated with these tornadoes. Based on damage, the Movilita village tornado was classified as an F1 type on the Fujita scale, and the Buftea and Ciobanu village tornadoes were classified as F0. Large scale forcing was provided by a vigorous upper level trough. The squall line developed in the warm sector of a low, ahead of the cold front. The Bucharest EEC-DWSR-2500C Doppler velocity depicted cyclonically rotational structures associated with the left end of the bow echo. In two hours this squall line traversed the southern part of the country. The northern end of the line preserved the bowed structures and high reflectivity gradient in front of them. The dry air associated with the descending rear inflow jet was evident as rear inflow notches in the reflectivity field of the Bucharest C-band radar and the Medgidia S-band WSR-98 D radar. The synoptic and mesoscale environment associated with 7 May 2005 bow echo had many similarities to the "dynamic" pattern described by John and Hirt (1987. Herein are analyzed the combined effects of synoptic and mesoscale circulations, together with the data provided by C-band EEC-DWSR-2500C and S-band WSR-98D radars, and the ECMWF and ALADIN model output data. Some operational aspects of the warning process are also discussed.

Number of warning information sources and decision making during tornadoes.

Science.gov (United States)

Luo, Jianjun; Cong, Zhen; Liang, Daan

2015-03-01

Taking proper protective action upon receiving tornado warnings is critical to reducing casualties. With more warning information sources becoming available, how the number of such information sources affects decision making should be quantitatively investigated. To examine how the number of warning information sources affected individuals' decisions to take protective action during tornadoes. A telephone survey using random sampling was conducted in 2012 with residents in Tuscaloosa AL and Joplin MO, resulting in a working sample of 782 respondents. Both cities were struck by violent tornadoes (Enhanced Fujita Scale [EF]4 and EF5) in 2011. The analysis was conducted in 2013. Logistic regression analysis showed that relative to having only one warning information source, having two and three or more warning information sources significantly increased the odds of taking protective action in Joplin but not in Tuscaloosa; having three or more sources had a significantly stronger effect on taking protective action in Joplin than in Tuscaloosa. Having an emergency preparation plan in both cities and being white in Tuscaloosa significantly increased the odds of taking protective action, whereas being divorced in Joplin reduced these odds. Receiving warnings from more warning information sources might be more beneficial in places with less previous exposure to tornadoes and for populations with lower awareness of a potential tornado and higher probability of receiving no warnings. Emergency management agencies and public health officials should give priority to these places and populations when formulating disaster mitigation decisions and policies. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Chaotic Financial Tornadoes

Science.gov (United States)

Jakimowicz, Aleksander

In contemporary economies classic business cycles are increasingly changing their form undergoing a transformation into phenomena that have been nicknamed financial tornados. A generalization of the Lotka-Volterra model can be used to describe these fast-changing processes. Economically speaking, the most useful are such dynamical systems in which wormholes appear. This article features application of a model with one population of prey and two populations of predators in order to explain the global financial crisis and the consequent phenomena.

Pre-Post Tornado Effects on Aggressive Children’s Psychological and Behavioral Adjustment Through One-Year Postdisaster

Science.gov (United States)

Lochman, John E.; Vernberg, Eric; Powell, Nicole P.; Boxmeyer, Caroline L.; Jarrett, Matthew; McDonald, Kristina; Qu, Lixin; Hendrickson, Michelle; Kassing, Francesca

2017-01-01

Objective Using a risk-resilience framework, this study examined how varying levels of exposure to a natural disaster (EF-4 tornado) and children’s characteristics (sex; anxiety) influenced the behavioral and psychological adjustment of children who shared a common risk factor predisaster (elevated aggression) prior to exposure through one-year postdisaster. Method Participants included 360 children in 4th–6th grades (65% male; 78% African American) and their parents from predominantly low-income households who were already participating in a longitudinal study of indicated prevention effects for externalizing outcomes when the tornado occurred in 2011. Fourth-grade children who were screened for overt aggressive behavior were recruited in three annual cohorts (120 per year, beginning in 2009). Parent-rated aggression and internalizing problems were assessed prior to the tornado (Wave 1), within a half-year after the tornado (Wave 2), and at a one-year follow-up (Wave 3). Children and parents rated their exposure to aspects of tornado-related traumatic experiences at Wave 3. Results Children displayed less reduction on aggression and internalizing problems if the children had experienced distress after the tornado or fears for their life, in combination with their pre-tornado level of anxiety. Higher levels of children’s and parents’ exposure to the tornado interacted with children’s lower baseline child anxiety to predict less reduction in aggression and internalizing problems one year after the tornado. Conclusion Higher levels of disaster exposure negatively affected at-risk children’s level of improvement in aggression and internalizing problems, when life threat (parent- and child-reported) and child-reported distress after the tornado were moderated by baseline anxiety. PMID:27841691

Development of a Probabilistic Tornado Wind Hazard Model for the Continental United States Volume I: Main Report

International Nuclear Information System (INIS)

Boissonnade, A; Hossain, Q; Kimball, J

2000-01-01

Since the mid-l980's, assessment of the wind and tornado risks at the Department of Energy (DOE) high and moderate hazard facilities has been based on the straight wind/tornado hazard curves given in UCRL-53526 (Coats, 1985). These curves were developed using a methodology that utilized a model, developed by McDonald, for severe winds at sub-tornado wind speeds and a separate model, developed by Fujita, for tornado wind speeds. For DOE sites not covered in UCRL-53526, wind and tornado hazard assessments are based on the criteria outlined in DOE-STD-1023-95 (DOE, 1996), utilizing the methodology in UCRL-53526; Subsequent to the publication of UCRL53526, in a study sponsored by the Nuclear Regulatory Commission (NRC), the Pacific Northwest Laboratory developed tornado wind hazard curves for the contiguous United States, NUREG/CR-4461 (Ramsdell, 1986). Because of the different modeling assumptions and underlying data used to develop the tornado wind information, the wind speeds at specified exceedance levels, at a given location, based on the methodology in UCRL-53526, are different than those based on the methodology in NUREG/CR-4461. In 1997, Lawrence Livermore National Laboratory (LLNL) was funded by the DOE to review the current methodologies for characterizing tornado wind hazards and to develop a state-of-the-art wind/tornado characterization methodology based on probabilistic hazard assessment techniques and current historical wind data. This report describes the process of developing the methodology and the database of relevant tornado information needed to implement the methodology. It also presents the tornado wind hazard curves obtained from the application of the method to DOE sites throughout the contiguous United States

A Database of Tornado Events as Perceived by the USArray Transportable Array Network

Science.gov (United States)

Tytell, J. E.; Vernon, F.; Reyes, J. C.

2015-12-01

Over the course of the deployment of Earthscope's USArray Transportable Array (TA) network there have numerous tornado events that have occurred within the changing footprint of its network. The Array Network Facility based in San Diego, California, has compiled a database of these tornado events based on data provided by the NOAA Storm Prediction Center (SPC). The SPC data itself consists of parameters such as start-end point track data for each event, maximum EF intensities, and maximum track widths. Our database is Antelope driven and combines these data from the SPC with detailed station information from the TA network. We are now able to list all available TA stations during any specific tornado event date and also provide a single calculated "nearest" TA station per individual tornado event. We aim to provide this database as a starting resource for those with an interest in investigating tornado signatures within surface pressure and seismic response data. On a larger scale, the database may be of particular interest to the infrasound research community

Plasma-liquid system with reverse vortex flow of 'tornado' type (TORNADO-LE)

International Nuclear Information System (INIS)

Nedybalyuk, O.A.; Chernyak, V.Ya.; Olszewski, S.V.

2010-01-01

The results of experimental investigations of the plasma in plasma-liquid system with reverse vortex flow of 'tornado' type are presented. Volt-ampere characteristic of discharge in the current range from 200 to 400 mA were measured. Emission spectra of plasma in range from 200 to 1100 nm were measured. Excitation temperatures (electronic T e * , vibrational T v * and rotational T r * ) were obtained. Emission spectra of hydroxyl OH were calculated.

Condensation-induced kinematics and dynamics of cyclones, hurricanes and tornadoes

International Nuclear Information System (INIS)

Makarieva, A.M.; Gorshkov, V.G.

2009-01-01

A universal equation is obtained for air pressure and wind velocity in cyclones, hurricanes and tornadoes as dependent on the distance from the center of the considered wind pattern driven by water vapor condensation. The obtained theoretical estimates of the horizontal profiles of air pressure and wind velocity, eye and wind wall radius in hurricanes and tornadoes and maximum values of the radial, tangential and vertical velocity components are in good agreement with empirical evidence.

Solar Tornado Prominences: Plasma Motions Along Filament Barbs

Science.gov (United States)

Panasenco, Olga; Velli, Marco; Martin, Sara F.; Rappazzo, Franco

2013-03-01

Recent high-resolution observations from the Solar Dynamic Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado prominences. This class of prominences was first introduced by E. Pettit in 1932, who studied them over many years up to 1950. High resolution and high cadence multi-wavelength data obtained by SDO reveal that the tornado-like properties of these prominences are mainly an illusion due to projection effects. We show that counterstreaming plasma motions with projected velocities up to +/- 45 km/sec along the prominence spine and barbs create a tornado-like impression when viewed at the limb. We demonstrate that barbs are often rooted at the intersection between 4-5 supergranular cells. We discuss the observed oscillations along the vertical parts of barbs and whether they may be related to vortex flows coming from the convection downdrafts at the intersection of supergranules (and possibly smaller convective cells) in the photosphere and their entrained magnetic field. The unwinding of magnetic threads near the photosphere via reconnection might be a source of the waves which are observed as oscillations in prominence barbs.

Climatology, storm morphologies, and environments of tornadoes in the British Isles: 1980–2012

OpenAIRE

Mulder, Kelsey J.; Schultz, David M.

2015-01-01

A climatology is developed for tornadoes during 1980–2012 in the British Isles, defined in this article as England, Scotland, Wales, Northern Ireland, Republic of Ireland, Channel Islands, and the Isle of Man. The climatology includes parent storm type, interannual variability, annual and diurnal cycles, intensities, oc- currence of outbreaks (defined as three or more tornadoes in the same day), geographic distribution, and environmental conditions derived from proximity soundings of tornadoe...

Daily variation in natural disaster casualties: information flows, safety, and opportunity costs in tornado versus hurricane strikes.

Science.gov (United States)

Zahran, Sammy; Tavani, Daniele; Weiler, Stephan

2013-07-01

Casualties from natural disasters may depend on the day of the week they strike. With data from the Spatial Hazard Events and Losses Database for the United States (SHELDUS), daily variation in hurricane and tornado casualties from 5,043 tornado and 2,455 hurricane time/place events is analyzed. Hurricane forecasts provide at-risk populations with considerable lead time. Such lead time allows strategic behavior in choosing protective measures under hurricane threat; opportunity costs in terms of lost income are higher during weekdays than during weekends. On the other hand, the lead time provided by tornadoes is near zero; hence tornados generate no opportunity costs. Tornado casualties are related to risk information flows, which are higher during workdays than during leisure periods, and are related to sheltering-in-place opportunities, which are better in permanent buildings like businesses and schools. Consistent with theoretical expectations, random effects negative binomial regression results indicate that tornado events occurring on the workdays of Monday through Thursday are significantly less lethal than tornados that occur on weekends. In direct contrast, and also consistent with theory, the expected count of hurricane casualties increases significantly with weekday occurrences. The policy implications of observed daily variation in tornado and hurricane events are considered. © 2012 Society for Risk Analysis.

Problems and proposed solution in evaluating tornado-borne missile speed

International Nuclear Information System (INIS)

Eguchi, Yuzuru; Sugimoto, Soichiro; Hattori, Yasuo; Hirakuchi, Hiromaru

2014-01-01

Large variation was found among the design values of tornado missile speed shown in current standards and guides in Japan and U.S. It was also found that the design missile speed indicated in the Guide issued by the Nuclear Regulation Authority of Japan is the most restrictive among them. The primary reason is due to the evaluation method where all the objects are unconditionally assumed to be placed in air as high as 40 m, even if the object should be on the ground. In order to solve this problem, the authors have adopted the tornado engineering model DBT-77 proposed by Dr. Fujita as a wind field model, and developed a numerical analysis code TONBOS with adding an object liftoff model. The effectiveness of the numerical analysis code was demonstrated by simulating liftoff and flight of a truck struck by an F3 tornado in Saroma. (author)

Evaluation of atmospheric-pressure change in tornado using Fujita model

International Nuclear Information System (INIS)

Shimizu, Juntaro; Ohtsubo, Shunsuke

2017-01-01

Evaluation of the atmospheric-pressure change (APC) in a tornado is necessary to assess the integrity of nuclear-related facilities. The Rankine model has been most frequently used to theoretically calculate the APC in a tornado. The result, however, is considered to be overly conservative because the Rankine model wind speed at the ground is larger than that in reality. On the other hand, the wind speed of the Fujita model is closer to that of actual tornadoes but is expressed by more complicated algebraic equations than that in the Rankine model. Also, because it is impossible to analytically derive the APC equation using the Fujita model, numerical computation is required. A previous study employed the finite element method (FEM) for such a purpose. However, a general-purpose FEM code often requires complicated input parameters. In order to conduct parametric studies to evaluate the integrity of facilities in various cases of tornadoes, the finite-difference method code “TORPEC”, which is specialized to analyze the APC, was developed as a convenient design tool. TORPEC is based on Poisson’s equation derived from the Navier-Stokes equation. It also runs on widely available technical calculation software such as Microsoft"® Excel VBA or MATLAB"®. Taking advantage of such convenience, various calculations have been conducted to reveal the characteristics of APC as functions of the maximum tangential wind speed, axial position and tornado radius. TORPEC is used as a benchmark in the existing paper. The case study results obtained by TORPEC show a constant ratio of the pressure drop of the Fujita model against the Rankine model. This factor can be used to derive the Fujita model result from the Rankine model result without FEM analysis. (author)

Explicating Experience: Development of a Valid Scale of Past Hazard Experience for Tornadoes.

Science.gov (United States)

Demuth, Julie L

2018-03-23

People's past experiences with a hazard theoretically influence how they approach future risks. Yet, past hazard experience has been conceptualized and measured in wide-ranging, often simplistic, ways, resulting in mixed findings about its relationship with risk perception. This study develops a scale of past hazard experiences, in the context of tornadoes, that is content and construct valid. A conceptual definition was developed, a set of items were created to measure one's most memorable and multiple tornado experiences, and the measures were evaluated through two surveys of the public who reside in tornado-prone areas. Four dimensions emerged of people's most memorable experience, reflecting their awareness of the tornado risk that day, their personalization of the risk, the intrusive impacts on them personally, and impacts experienced vicariously through others. Two dimensions emerged of people's multiple experiences, reflecting common types of communication received and negative emotional responses. These six dimensions are novel in that they capture people's experience across the timeline of a hazard as well as intangible experiences that are both direct and indirect. The six tornado experience dimensions were correlated with tornado risk perceptions measured as cognitive-affective and as perceived probability of consequences. The varied experience-risk perception results suggest that it is important to understand the nuances of these concepts and their relationships. This study provides a foundation for future work to continue explicating past hazard experience, across different risk contexts, and for understanding its effect on risk assessment and responses. © 2018 Society for Risk Analysis.

Axisymmetric Tornado Simulations with a Semi-Slip Boundary

Directory of Open Access Journals (Sweden)

Brian H. Fiedler

2017-12-01

Full Text Available The structure of natural tornadoes and simulated analogs are sensitive to the lower boundary condition for friction. Three-dimensional numerical simulations of storms require a choice for turbulence parameterizations and resolution of wind near the lower boundary. This article explores some of the consequences of choices of a surface drag coefficient on the structure of a mature simulated tornado, using a conventional axisymmetric model. The surface drag parameterization is explored over the range of the semi-slip condition, including the extremes of no-slip and free-slip. A moderate semi-slip condition allows for an extreme pressure deficit, but without the unrealistic vortex breakdown of the no-slip condition.

On necessity of revaluation of nuclear power safety of Ukraine in the tornado hazardous areas

International Nuclear Information System (INIS)

Skalozubov, V.I.; Gablaya, T.V.; Vasilchenko, S.V.; Kozlov, I.V.

2015-01-01

The article contains the main provisions regulating the tornado danger of objects of atomic energy, as well as analysis of the known results of evaluations of the impact of hurricanes on the safety of nuclear power plants of Ukraine, received in the ''before'' and ''post Fukushima'' periods. As a result of analysis is insufficient justification to the estimated frequency of passing tornadoes and exclusion from consideration emergency events with flooding of indus-trial sites under the influence of tornadoes not less than 2-th class intensity, defined a reassessment of NPP safety of Ukraine taking into account reasonably established performance tornado dangerous areas and lessons Fukushima accident

Casualty Risk From Tornadoes in the United States is Highest in Urbanized Areas Across the Mid South

Science.gov (United States)

Fricker, T.; Elsner, J.

2017-12-01

Risk factors for tornado casualties are well known. Less understood is how and to what degree these determinants, after controlling for strength and urban density, vary spatially and temporally. Here we fit models to casualty counts from all casualty-producing tornadoes since 1995 in order to quantify the interactions between urbanization and energy on casualty rates. Results from the models show that the more urbanized areas of the Mid South are substantively and significantly more vulnerable to casualties from tornadoes than elsewhere in the country. Casualty rates are significantly higher on the weekend for tornadoes in this region. Night and day casualty rates are similar regardless of where they occur. Higher vulnerability to casualties from tornadoes occurring in more urbanized areas correspond significantly with greater percentages of elderly people. Many of the micro cities in the Mid South are threatened by tornadoes annually and this threat might potentially be exacerbated by climate change.

Development of a tornado wind speed hazard model for limited area (TOWLA) for nuclear power plants at a coastline

International Nuclear Information System (INIS)

Hirakuchi, Hiromaru; Nohara, Daisuke; Sugimoto, Soichiro; Eguchi, Yuzuru; Hattori, Yasuo

2016-01-01

It is necessary for Japanese electric power companies to assess tornado risks on the nuclear power plants according to a new regulation in 2013. The new regulatory guide recommends to select a long narrow strip area along a coast line with the width of 5 km to the seaward and landward sides as a target area of tornado risk assessment, because most of Japanese tornados have been reported near the coast line, where all of Japanese nuclear power plants are located. However, it is very difficult to evaluate a tornado hazard along a coast line, because there is no available information of F-scale and damage length/width on tornadic waterspouts. The purpose of this study is to propose a new tornado wind hazard model for limited area (TOWLA), which can be apply to a long narrow strip area along a coastline. In order to consider tornadic waterspouts moved inland, we evaluate the number of waterspouts entering/passing the targeting area, and add them to the total number of the tornado occurred in the area. A characteristic of the model is to use 'segment lengths' instead of damage lengths. The segment length is a part of the tornado foot print in the long narrow strip area. We show two methods for segment length computation. One is based on tornado records; latitude and longitude of tornado genesis and dissipation locations. The other is to compute the expected segment length based on the geometrical relationship among the damage length, area width, and directional characteristics of tornado movement. The new model can also consider the variation of tornado intensity along the path length and across the path width. (author)

Utilizing Tornado Data for Classroom Exercises.

Science.gov (United States)

Kohler, Fred

Exercises were developed using tornado statistics to provide students with a better understanding of the spatial and temporal characteristics of these phenomena in the United States. Four categories of exercises were considered beginning with the simplest and progressing to the more complex. The first set of exercises required students to…

Tornado missile simulation and design methodology. Volume 2: model verification and data base updates. Final report

International Nuclear Information System (INIS)

Twisdale, L.A.; Dunn, W.L.

1981-08-01

A probabilistic methodology has been developed to predict the probabilities of tornado-propelled missiles impacting and damaging nuclear power plant structures. Mathematical models of each event in the tornado missile hazard have been developed and sequenced to form an integrated, time-history simulation methodology. The models are data based where feasible. The data include documented records of tornado occurrence, field observations of missile transport, results of wind tunnel experiments, and missile impact tests. Probabilistic Monte Carlo techniques are used to estimate the risk probabilities. The methodology has been encoded in the TORMIS computer code to facilitate numerical analysis and plant-specific tornado missile probability assessments

Investigation of HEPA filters subjected to tornado pressure pulses

International Nuclear Information System (INIS)

Gregory, W.S.; Horak, H.L.; Smith, P.R.; Ricketts, C.

1977-03-01

An experimental program is described that will determine the response of 0.6-x 0.6-m (24-x 24-in.) high-efficiency particulate air (HEPA) filters to tornado-induced pressure transients. A blow-down system will be used to impose pressure differentials across the filters. Progress in construction of this system is reported with a description of the component parts and their functions. The test facility is essentially complete with the exception of an air dryer system that has not yet been delivered. Initial structural testing will begin in March 1977. A description is given of the instrumentation needed to measure air pressure, velocity, turbulence, humidity and particulate concentration. This instrumentation includes pressure transducers, humidity equipment, laser Doppler velocimeters (LDV), signal processors and a data acquisition system. Operational theory of the LDV and its proposed use as a particle counting device are described

Tornado: School Damage Tops $3 Million.

Science.gov (United States)

Story, Nancy

1999-01-01

Describes efforts by the publications staff of North Hall High School (Gainesville, Georgia) to cover a tornado and its aftermath. Notes that the first issue published after the storm focused in intrusion by the media. Suggests that an anniversary issues was more effective in achieving the emotional catharsis the school needed. (RS)

Laboratory Study of Topographic Effects on the Near-surface Tornado Flow Field

Science.gov (United States)

Razavi, Alireza; Sarkar, Partha P.

2018-03-01

To study topographic effects on the near-surface tornado flow field, the Iowa State University tornado simulator was used to simulate a translating tornado passing over three different two-dimensional topographies: a ridge, an escarpment and a valley. The effect of the translation speed on maximum horizontal wind speeds is observed for translation speeds of 0.15 and 0.50 m s^{-1} , with the lower value resulting in a larger maximum horizontal wind speed. The tornado translation over the three topographies with respect to flat terrain is assessed for changes in: (a) the maximum horizontal wind speeds in terms of the flow-amplification factor; (b) the maximum aerodynamic drag in terms of the tornado speed-up ratio; (c) the maximum duration of exposure at any location to high wind speeds of a specific range in terms of the exposure amplification factor. Results show that both the maximum wind amplification factor of 14%, as well as the maximum speed-up ratio of 14%, occur on the ridge. For all topographies, the increase in aerodynamic drag is observed to be maximized for low-rise buildings, which illustrates the importance of the vertical profiles of the horizontal wind speed near the ground. The maximum exposure amplification factors, estimated for the range of wind speeds corresponding to the EF2 (50-60 m s^{-1} ) and EF3 (61-75 m s^{-1}) scales, are 86 and 110% for the ridge, 4 and 60% for the escarpment and - 6 and 47% for the valley, respectively.

Working after a tornado: a survey of hospital personnel in Joplin, Missouri.

Science.gov (United States)

Charney, Rachel; Rebmann, Terri; Flood, Robert G

2014-01-01

In 2011, an EF5 tornado hit Joplin, MO, requiring complete evacuation of 1 hospital and a patient surge to another. We sought to assess the resilience of healthcare workers in these hospitals as measured by number reporting to work, willingness to work, personal disaster preparedness, and childcare responsibilities following the disaster. In May 2013, a survey was distributed to healthcare workers at both Joplin hospitals that asked them to report their willingness to work and personal disaster preparedness following various disaster scenarios. For those with childcare responsibilities, scheduling, costs, and impact of hypothetical alternative childcare programs were considered in the analyses. A total of 1,234 healthcare workers completed the survey (response rate: 23.4%). Most (87.8%) worked the week following the Joplin tornado. Healthcare workers report more willingness to work during a future earthquake or tornado compared to their pre-Joplin tornado attitudes (86.2 vs 88.4%, t=-4.3, ptornado personal disaster preparedness, but only preevent preparedness was a significant predictor of postevent preparedness. Nearly half (48.5%, n=598) had childcare responsibilities; 61% (n=366) had childcare needs the week of the tornado, and 54% (n=198) required the use of alternative childcare. If their hospital had provided alternative childcare, 51% would have used it and 42% felt they would have been more willing to report to work. Most healthcare workers reported to work following this disaster, demonstrating true resilience. Disaster planners should be aware of these perceptions as they formulate their own emergency operation plans.

Doppler Radar and Cloud-to-Ground Lightning Observations of a Severe Outbreak of Tropical Cyclone Tornadoes

Science.gov (United States)

McCaul, Eugene W., Jr.; Buechler, Dennis; Cammarata, Michael; Arnold, James E. (Technical Monitor)

2002-01-01

Data from a single WSR-88D Doppler radar and the National Lightning Detection Network are used to examine the characteristics of the convective storms that produced a severe tornado outbreak within Tropical Storm Beryl's remnants on 16 August 1994. Comparison of the radar data with reports of tornadoes suggests that only 12 cells produced the 29 tornadoes that were documented in Georgia and the Carolinas on that date. Six of these cells spawned multiple tornadoes, and the radar data confirm the presence of miniature supercells. One of the cells was identifiable on radar for 11 hours, spawning tornadoes over a time period spanning approximately 6.5 hours. Time-height analyses of the three strongest supercells are presented in order to document storm kinematic structure and evolution. These Beryl mini-supercells were comparable in radar-observed intensity but much more persistent than other tropical cyclone-spawned tornadic cells documented thus far with Doppler radars. Cloud-to-ground lightning data are also examined for all the tornadic cells in this severe swarm-type tornado outbreak. These data show many of the characteristics of previously reported heavy-precipitation supercells. Lightning rates were weak to moderate, even in the more intense supercells, and in all the storms the lightning flashes were almost entirely negative in polarity. No lightning at all was detected in some of the single-tornado storms. In the stronger cells, there is some evidence that lightning rates can decrease during tornadogenesis, as has been documented before in some midlatitude tornadic storms. A number of the storms spawned tornadoes just after producing their final cloud-to-ground lightning flashes. These findings suggest possible benefits from implementation of observing systems capable of monitoring intracloud as well as cloud-to-ground lightning activity.

ON THE MAGNETISM AND DYNAMICS OF PROMINENCE LEGS HOSTING TORNADOES

International Nuclear Information System (INIS)

Martínez González, M. J.; Ramos, A. Asensio; Arregui, I.; Collados, M.; Beck, C.; Rodríguez, J. de la Cruz

2016-01-01

Solar tornadoes are dark vertical filamentary structures observed in the extreme ultraviolet associated with prominence legs and filament barbs. Their true nature and relationship to prominences requires an understanding of their magnetic structure and dynamic properties. Recently, a controversy has arisen: is the magnetic field organized forming vertical, helical structures or is it dominantly horizontal? And concerning their dynamics, are tornadoes really rotating or is it just a visual illusion? Here we analyze four consecutive spectro-polarimetric scans of a prominence hosting tornadoes on its legs, which helps us shed some light on their magnetic and dynamical properties. We show that the magnetic field is very smooth in all the prominence, which is probably an intrinsic property of the coronal field. The prominence legs have vertical helical fields that show slow temporal variation that is probably related to the motion of the fibrils. Concerning the dynamics, we argue that (1) if rotation exists, it is intermittent, lasting no more than one hour, and (2) the observed velocity pattern is also consistent with an oscillatory velocity pattern (waves).

ON THE MAGNETISM AND DYNAMICS OF PROMINENCE LEGS HOSTING TORNADOES

Energy Technology Data Exchange (ETDEWEB)

Martínez González, M. J.; Ramos, A. Asensio; Arregui, I.; Collados, M. [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Beck, C. [National Solar Observatory, Sacramento Peak P.O. Box 62, Sunspot, NM 88349 (United States); Rodríguez, J. de la Cruz [Institute for Solar Physics, Department of Astronomy, Stockholm University, Albanova University Center, SE-10691 Stockholm (Sweden)

2016-07-10

Solar tornadoes are dark vertical filamentary structures observed in the extreme ultraviolet associated with prominence legs and filament barbs. Their true nature and relationship to prominences requires an understanding of their magnetic structure and dynamic properties. Recently, a controversy has arisen: is the magnetic field organized forming vertical, helical structures or is it dominantly horizontal? And concerning their dynamics, are tornadoes really rotating or is it just a visual illusion? Here we analyze four consecutive spectro-polarimetric scans of a prominence hosting tornadoes on its legs, which helps us shed some light on their magnetic and dynamical properties. We show that the magnetic field is very smooth in all the prominence, which is probably an intrinsic property of the coronal field. The prominence legs have vertical helical fields that show slow temporal variation that is probably related to the motion of the fibrils. Concerning the dynamics, we argue that (1) if rotation exists, it is intermittent, lasting no more than one hour, and (2) the observed velocity pattern is also consistent with an oscillatory velocity pattern (waves).

Characterization of the wind loads and flow fields around a gable-roof building model in tornado-like winds

Energy Technology Data Exchange (ETDEWEB)

Hu, Hui; Yang, Zifeng; Sarkar, Partha [Iowa State University, Department of Aerospace Engineering, Ames, IA (United States); Haan, Fred [Iowa State University, Department of Aerospace Engineering, Ames, IA (United States); Rose-Hulman Institute of Technology, Department of Mechanical Engineering, Terre Haute, IN (United States)

2011-09-15

An experimental study was conducted to quantify the characteristics of a tornado-like vortex and to reveal the dynamics of the flow-structure interactions between a low-rise, gable-roof building model and swirling, turbulent tornado-like winds. The experimental work was conducted by using a large-scale tornado simulator located in the Aerospace Engineering Department of Iowa State University. In addition to measuring the pressure distributions and resultant wind loads acting on the building model, a digital Particle Image Velocimetry system was used to conduct detailed flow field measurements to quantify the evolution of the unsteady vortices and turbulent flow structures around the gable-roof building model in tornado-like winds. The effects of important parameters, such as the distance between the centers of the tornado-like vortex and the test model and the orientation angles of the building model related to the tornado-like vortex, on the evolutions of the wake vortices and turbulent flow structures around the gable-roof building model as well as the wind loads induced by the tornado-like vortex were assessed quantitatively. The detailed flow field measurements were correlated with the surface pressure and wind load measurements to elucidate the underlying physics to gain further insight into flow-structure interactions between the gable-roof building model and tornado-like winds in order to provide more accurate prediction of wind damage potential to built structures. (orig.)

Tornado Damage Assessment: Reconstructing the Wind Through Debris Tracking and Treefall Pattern Analysis

Science.gov (United States)

Godfrey, C. M.; Peterson, C. J.; Lombardo, F.

2017-12-01

Efforts to enhance the resilience of communities to tornadoes requires an understanding of the interconnected nature of debris and damage propagation in both the built and natural environment. A first step toward characterizing the interconnectedness of these elements within a given community involves detailed post-event surveys of tornado damage. Such damage surveys immediately followed the 22 January 2017 EF3 tornadoes in the southern Georgia towns of Nashville and Albany. After assigning EF-scale ratings to impacted structures, the authors geotagged hundreds of pieces of debris scattered around selected residential structures and outbuildings in each neighborhood and paired each piece of debris with its source structure. Detailed information on trees in the vicinity of the structures supplements the debris data, including the species, dimensions, location, fall direction, and level of damage. High-resolution satellite imagery helps to identify the location and fall direction of hundreds of additional forest trees. These debris and treefall patterns allow an estimation of the near-surface wind field using a Rankine vortex model coupled with both a tree stability model and an infrastructure fragility model that simulates debris flight. Comparisons between the modeled damage and the actual treefall and debris field show remarkable similarities for a selected set of vortex parameters, indicating the viability of this approach for estimating enhanced Fujita scale levels, determining the near-surface wind field of a tornado during its passage through a neighborhood, and identifying how debris may contribute to the overall risk from tornadoes.

ARE TORNADO-LIKE MAGNETIC STRUCTURES ABLE TO SUPPORT SOLAR PROMINENCE PLASMA?

Energy Technology Data Exchange (ETDEWEB)

Luna, M.; Moreno-Insertis, F. [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife (Spain); Priest, E. [Mathematics Institute, University of St Andrews, St Andrews KY16 9SS (United Kingdom)

2015-07-20

Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

Facebook and Twitter, communication and shelter, and the 2011 Tuscaloosa tornado.

Science.gov (United States)

Stokes, Courtney; Senkbeil, Jason C

2017-01-01

This paper represents one of the first attempts to analyse the many ways in which Facebook and Twitter were used during a tornado disaster. Comparisons between five randomly selected campus samples and a city of Tuscaloosa, Alabama, sample revealed that campus samples used Facebook and Twitter significantly more both before and after the tornado, but Facebook usage was not significantly different after the event. Furthermore, differences in social media usage and other forms of communication before the tornado were found for age, education, and years lived in Tuscaloosa. Generally, age and education were inversely proportionate to social media usage. Influences on shelter-seeking actions varied between social media users and three random samples of non-social media users; however, it appears that social media respondents were likely to be using a smartphone simultaneously to access warning polygon information, to receive text message alerts, and to listen or respond to environmental cues. © 2017 The Author(s). Disasters © Overseas Development Institute, 2017.

ARE TORNADO-LIKE MAGNETIC STRUCTURES ABLE TO SUPPORT SOLAR PROMINENCE PLASMA?

International Nuclear Information System (INIS)

Luna, M.; Moreno-Insertis, F.; Priest, E.

2015-01-01

Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present

Are Tornado-Like Magnetic Structures Able to Support Solar Prominence Plasma?

Science.gov (United States)

Ogunjo, S. T.; Luna Bennasar, M.; Moreno-Insertis, F.; Priest, E. R.

2015-12-01

Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

TORNADO-LIKE EVOLUTION OF A KINK-UNSTABLE SOLAR PROMINENCE

Energy Technology Data Exchange (ETDEWEB)

Wang, Wensi; Liu, Rui; Wang, Yuming, E-mail: rliu@ustc.edu.cn [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei 230026 (China)

2017-01-01

We report on the tornado-like evolution of a quiescent prominence on 2014 November 1. The eastern section of the prominence first rose slowly, transforming into an arch-shaped structure as high as ∼150 Mm above the limb; the arch then writhed moderately in a left-handed sense, while the original dark prominence material emitted in the Fe ix 171 Å passband, and a braided structure appeared at the eastern edge of the warped arch. The unraveling of the braided structure was associated with a transient brightening in the EUV and apparently contributed to the formation of a curtain-like structure (CLS). The CLS consisted of myriad thread-like loops rotating counterclockwise about the vertical if viewed from above. Heated prominence material was observed to slide along these loops and land outside the filament channel. The tornado eventually disintegrated and the remaining material flew along a left-handed helical path constituting approximately a full turn, as corroborated through stereoscopic reconstruction, into the cavity of the stable, western section of the prominence. We suggest that the tornado-like evolution of the prominence was governed by the helical kink instability, and that the CLS formed through magnetic reconnections between the prominence field and the overlying coronal field.

Tornado Emergency Readiness Planning for Schools.

Science.gov (United States)

Wisconsin State Dept. of Public Instruction, Madison.

A place of safe refuge in the event of violent natural forces or a tornado should be included in the design of all new school buildings. Existing a school buildings should be analyzed by the architect, contractor, or engineer to determine if a safe place exists or if one can be readily adapted. Most criteria for fallout shelters are the same for…

Toward better assessment of tornado potential in typhoons: Significance of considering entrainment effects for CAPE

Science.gov (United States)

Sueki, Kenta; Niino, Hiroshi

2016-12-01

The characteristics of typhoons that spawned tornadoes (tornadic typhoons: TTs) in Japan from 1991 to 2013 were investigated by composite analysis using the Japanese 55 year Reanalysis and compared with those of typhoons that did not spawn tornadoes (nontornadic typhoons: NTs). We found that convective available potential energy (CAPE), which considers the effects of entrainment (entraining CAPE: E-CAPE), and storm-relative environmental helicity (SREH) are significantly large in the northeast quadrant of TTs where tornadoes frequently occur and that E-CAPE and SREH in that quadrant for TTs are larger than those for NTs. On the other hand, ordinary CAPE without entrainment does not account for the spatial distribution of tornado occurrences nor does it distinguish TTs from NTs. E-CAPE is sensitive to humidity in the midtroposphere; thus, it is effective for detecting a conditionally unstable layer up to about 550 hPa, which is distinctive of TTs.

Impact of dual-polarization radar technology and Twitter on the Hattiesburg, Mississippi tornado.

Science.gov (United States)

Cates, Alexis L; Arnold, Brent W; Cooper, Guy Paul; Yeager, Violet; Stake, Josh; Ali, Mohammed; Calderone, Richard C; Wilkinson, James; Hsu, Edbert; Parrillo, Steven; Piper, Steven; Subbarao, Italo

2013-12-01

Dual-Polarization Radar and Twitter were analyzed to determine the impact on injuries sustained by the Hattiesburg EF-4 tornado. Tracking data provided from the Dual-Pol radar systems in National Weather Service Jackson were reviewed. Twitter data from four local Twitter handles were obtained. The change in tweets and followers for the day of the storm were compared to historical averages. A Student t-test was utilized in determining statistical significance (ptornado. An Injury Severity Score (ISS) was calculated for trauma records related to the tornado. Radar detection of the tornado gave approximately 30 minutes of advanced warning time. Statistical significance in follower growth was seen in all four Twitter handles. Out of 50 patients, the average ISS was 3.9 with a range of 1 to 29. There were zero fatalities. An ISS average of 3.9 was significantly less than two previous tornadoes of similar strength that occurred prior to increased usage of Dual-pol radar and Twitter as a means for communicating severe weather information. Early detection from Dual-pol radar improved warning time. Tweets informed citizens to seek appropriate shelter. (Disaster Med Public Health Preparedness. 2013;7:585-592).

Tornado Warning Perception and Response: Integrating the Roles of Visual Design, Demographics, and Hazard Experience.

Science.gov (United States)

Schumann, Ronald L; Ash, Kevin D; Bowser, Gregg C

2018-02-01

Recent advancements in severe weather detection and warning dissemination technologies have reduced, but not eliminated, large-casualty tornado hazards in the United States. Research on warning cognition and behavioral response by the public has the potential to further reduce tornado-related deaths and injuries; however, less research has been conducted in this area compared to tornado research in the physical sciences. Extant research in this vein tends to bifurcate. One branch of studies derives from classic risk perception, which investigates cognitive, affective, and sociocultural factors in relation to concern and preparation for uncertain risks. Another branch focuses on psychological, social, and cultural factors implicated in warning response for rapid onset hazards, with attention paid to previous experience and message design. Few studies link risk perceptions with cognition and response as elicited by specific examples of warnings. The present study unites risk perception, cognition, and response approaches by testing the contributions of hypothesized warning response drivers in one set of path models. Warning response is approximated by perceived fear and intended protective action as reported by survey respondents when exposed to hypothetical tornado warning scenarios. This study considers the roles of hazard knowledge acquisition, information-seeking behaviors, previous experience, and sociodemographic factors while controlling for the effects of the visual warning graphic. Findings from the study indicate the primacy of a user's visual interpretation of a warning graphic in shaping tornado warning response. Results also suggest that information-seeking habits, previous tornado experience, and local disaster culture play strong influencing roles in warning response. © 2017 Society for Risk Analysis.

A study on the regionalization of tornadogenesis for the domestic largest scale of tornado

International Nuclear Information System (INIS)

Sugimoto, Soichiro; Nohara, Daisuke; Hirakuchi, Hiromaru

2014-01-01

A new regulatory guide has been issued by the Nuclear Regulation Authority of Japan since the last year. According to this guide, electric power companies have to assess the influence of tornadoes on their nuclear power plants for operation. The purpose of this study is to evaluate the likelihood of the occurrence of F3 tornadoes, which are the largest encountered in Japan, and to consider the possibility of the regionalization of the maximum wind speed. Then, mesoscale analysis with a numerical meteorological model and re-analysis data is performed along with synoptic scale analysis. Especially, tornado parameters such as SReH (Storm Relative Helicity) and CAPE (Convective Available Potential Energy) are used for evaluating the potential tornadogenesis of F3 tornado. Both analyses indicate that favorable meteorological condition tends to occur in the coastal zones in the Pacific side west of Ibaraki and around Kyushu island. The frequency in these zones is different from the one in the other area in the order of 1 or 2, which is large enough for regionalization. (author)

Assessment of the Public Health Risks and Impact of a Tornado in Funing, China, 23 June 2016: A Retrospective Analysis.

Science.gov (United States)

Wang, Kaiwen; Zhong, Shuang; Wang, Xiaoye; Wang, Zhe; Yang, Lianping; Wang, Qiong; Wang, Suhan; Sheng, Rongrong; Ma, Rui; Lin, Shao; Liu, Wenyu; Zu, Rongqiang; Huang, Cunrui

2017-10-10

(1) Background: Tornadoes are one of the deadliest disasters but their health impacts in China are poorly investigated. This study aimed to assess the public health risks and impact of an EF-4 tornado outbreak in Funing, China; (2) Methods: A retrospective analysis on the characteristics of tornado-related deaths and injuries was conducted based on the database from the Funing's Center for Disease Control and Prevention (CDC) and Funing People's Hospital. A change-point time-series analysis of weekly incidence for the period January 2010 to September 2016 was used to identify sensitive infectious diseases to the tornado; (3) Results: The 75 to 84 years old group was at the highest risk of both death (RR = 82.16; 95% CIs = 19.66, 343.33) and injury (RR = 31.80; 95% CI = 17.26, 58.61), and females were at 53% higher risk of death than males (RR = 1.53; 95% CIs = 1.02, 2.29). Of the 337 injuries, 274 injuries (81%) were minor. Most deaths occurred indoors (87%) and the head (74%) was the most frequent site of trauma during the tornado. Five diseases showed downward change-points; (4) Conclusions: The experience of the Funing tornado underscores the relative danger of being indoors during a tornado and is successful in avoiding epidemics post-tornado. Current international safety guidelines need modification when generalized to China.

Assessment of the Public Health Risks and Impact of a Tornado in Funing, China, 23 June 2016: A Retrospective Analysis

Directory of Open Access Journals (Sweden)

Kaiwen Wang

2017-10-01

Full Text Available (1 Background: Tornadoes are one of the deadliest disasters but their health impacts in China are poorly investigated. This study aimed to assess the public health risks and impact of an EF-4 tornado outbreak in Funing, China; (2 Methods: A retrospective analysis on the characteristics of tornado-related deaths and injuries was conducted based on the database from the Funing’s Center for Disease Control and Prevention (CDC and Funing People’s Hospital. A change-point time-series analysis of weekly incidence for the period January 2010 to September 2016 was used to identify sensitive infectious diseases to the tornado; (3 Results: The 75 to 84 years old group was at the highest risk of both death (RR = 82.16; 95% CIs = 19.66, 343.33 and injury (RR = 31.80; 95% CI = 17.26, 58.61, and females were at 53% higher risk of death than males (RR = 1.53; 95% CIs = 1.02, 2.29. Of the 337 injuries, 274 injuries (81% were minor. Most deaths occurred indoors (87% and the head (74% was the most frequent site of trauma during the tornado. Five diseases showed downward change-points; (4 Conclusions: The experience of the Funing tornado underscores the relative danger of being indoors during a tornado and is successful in avoiding epidemics post-tornado. Current international safety guidelines need modification when generalized to China.

Residential tornado safe room from commodity wood products – impact and wind pressure testing

Science.gov (United States)

Robert H. Falk; James J. Bridwell; C. Adam Senalik; Marshall Begel

2018-01-01

A tornado safe room is a shelter designed to provide protection during a tornado and is specifically engineered to resist the high wind pressures and debris impact generated by these high wind events. The required performance criteria of these shelters has been established and is found in the International Code Council Standard for the Design and Construction of Storm...

Tornado detection data reduction and analysis

Science.gov (United States)

Davisson, L. D.

1977-01-01

Data processing and analysis was provided in support of tornado detection by analysis of radio frequency interference in various frequency bands. Sea state determination data from short pulse radar measurements were also processed and analyzed. A backscatter simulation was implemented to predict radar performance as a function of wind velocity. Computer programs were developed for the various data processing and analysis goals of the effort.

Ventilation systems analysis during tornado conditions. Progress report, January--June 1975

International Nuclear Information System (INIS)

Bennett, G.A.; Gregory, W.S.; Smith, P.R.

1975-11-01

The principal concern of this investigation is to develop the capability to simulate the dynamic effects of a tornado depressurization on a ventilation system. The basic formulation and solution of the two-zone series model ventilation subsystem is based on lumped parameter component response equations, the isothermal compression of air, and the conservation of mass. Solutions based on these assumptions are also presented for the two-zone series model with natural bypass, the two-zone series model with recirculation, and the natural branching model. A parameter study is presented comparing the effects of changes in system resistance, system capacitance, and variable tornado depressurization rates. The adaptability of the basic formulation to adiabatic compression of air and the addition of duct resistance is examined. A quasi-steady formulation is introduced and preliminary considerations of the importance of inertia are presented. Preliminary conclusions in this area indicate that inertial effects can be neglected. For relatively long ducts slow shock development appears possible. Work on the effect of tornado depressurization rates as related to shock development and on the importance of inertia effects is continuing

Massive pediatric neurosurgical injuries and lessons learned following a tornado disaster in Alabama.

Science.gov (United States)

Chern, Joshua J; Miller, Joseph H; Tubbs, R Shane; Whisenhunt, Thomas R; Johnston, James M; Wellons, John C; Rozzelle, Curtis J; Blount, Jeffrey P; Oakes, W Jerry

2011-12-01

A large volume of patients presented to a Level I pediatric trauma center during and after a recent tornado disaster. Injuries of the central and peripheral nervous systems and the medical responses of a pediatric neurosurgical team are reviewed. The clinical courses of patients who suffered cranial, spinal, and peripheral nerve injuries due to the tornado storm are reported. The clinical actions taken by the neurosurgical team during and after the event are reviewed and the lessons learned are discussed. The tornado storm system moved through the Tuscaloosa and Birmingham metropolitan areas on the early evening hours of April 27, 2011. Twenty-four patients received care from the neurosurgical team. A total of 11 cranial (including placement of an external ventricular drain), 2 spine, and 2 peripheral procedures were performed for the victims. Nine procedures were performed within the first 12 hours of the event, and an additional 6 surgeries were performed in the following 24 hours. Injuries of the peripheral nervous system often presented in a delayed fashion. Several key components were identified that enabled adequate neurosurgical care for a large influx of acute patients. Massive casualties due to tornados are rare. A well-organized physician team working with the hospital administration may decrease the mortality and morbidity of such events.

Full-scale impact test data for tornado-missile design of nuclear plants

International Nuclear Information System (INIS)

Stephenson, A.E.; Sliter, G.E.

1977-01-01

It is standard practice to consider the effects of low-probability impacts of tornado-borne debris (''tornado missiles'' such as utility poles and steel pipes) in the structural design of nuclear power plants in the United States. To provide data that can be used directly in the design procedure, a series of full-scale tornado-missile impact tests was performed. This paper is a brief summary of the results and conclusions from these tests. The tests consisted of reinforced concrete panels impacted by poles, pipes, and rods propelled by a rocket sled. The panels were constructed to current minimum standards and had thicknesses typical of auxiliary buildings of nuclear power plants. A specific objective was the determination of the impact velocities below which the panels do not experience backface scabbing. Another objective was to assess the adequacy of (1) conventional design formulae for penetration and scabbing and (2) conventional design methods for overall structural response. Test missiles and velocities represented those in current design standards. Missiles included utility poles, steel pipes, and steel bars. It is important to interpret the data in this paper in recognition that the test conditions represent conservative assumptions regarding maximum wind speeds, injection of the missile into the wind stream, aerodynamic trajectory, and orientation of missile at impact. Even with the severe assumptions made, the full-scale tests described demonstrate the ability of prototypical nuclear plant walls and roofs to provide adequate protection against postulated tornado-missile impact

Four hospitals in the path of killer tornadoes--what happened before ... during ... after.

Science.gov (United States)

Friedrick, Joanne

2012-01-01

In mid-and late-April, late May, and early June of 2011, tornadoes swept across states in the Midwest, South, Southeast, and even New England, killing hundreds, injuring thousands, destroying property in the billions in both rural and urban areas. Some hospitals in areas where the tornadoes struck did not escape damage and one was destroyed. This article describes what happened at four hospitals in cities hardest hit by the storms and the many roles played by security officers.

Using Unmanned Aerial Vehicles (UAVs) to Modeling Tornado Impacts

Science.gov (United States)

Wagner, M.; Doe, R. K.

2017-12-01

Using Unmanned Aerial Vehicles (UAVs) to assess storm damage is a useful research tool. Benefits include their ability to access remote or impassable areas post-storm, identify unknown damages and assist with more detailed site investigations and rescue efforts. Technological advancement of UAVs mean that they can capture high resolution images often at an affordable price. These images can be used to create 3D environments to better interpret and delineate damages from large areas that would have been difficult in ground surveys. This research presents the results of a rapid response site investigation of the 29 April 2017 Canton, Texas, USA, tornado using low cost UAVs. This was a multiple, high impact tornado event measuring EF4 at maximum. Rural farmland was chosen as a challenging location to test both equipment and methodology. Such locations provide multiple impacts at a variety of scales including structural and vegetation damage and even animal fatalities. The 3D impact models allow for a more comprehensive study prior to clean-up. The results show previously unseen damages and better quantify damage impacts at the local level. 3D digital track swaths were created allowing for a more accurate track width determination. These results demonstrate how effective the use of low cost UAVs can be for rapid response storm damage assessments, the high quality of data they can achieve, and how they can help us better visualize tornado site investigations.

The effects of the April 2011 tornado outbreak on personal preparedness in Jefferson County, Alabama.

Science.gov (United States)

McCormick, Lisa C; Pevear, Jesse; Rucks, Andrew C; Ginter, Peter M

2014-01-01

The purpose of this study was to examine the effects of a tornado disaster on the personal preparedness of local residents to determine (1) to what extent the tornado outbreak experience had altered preparedness awareness, willingness to act, and levels of personal preparedness of residents as measured by possession of a preparedness kit; and (2) what effect this experience had on the variables associated with having a complete disaster preparedness kit. Two random digit-dialed surveys were completed following the Behavioral Risk Factor Surveillance System protocols. The pre-tornado survey was conducted between October and December 2010 and the post-tornado survey was conducted between January and March 2012. After the April 2011 tornado outbreak, 86.08% of the respondents (n = 1364) reported that they had thought more about personal or family preparedness and 59.65% (n = 907) reported that they had taken actions to increase their level of preparedness. Overall, general awareness of preparedness media campaigns increased significantly (almost 24%; P < .0001), as did the percentage of those having a complete disaster preparedness kit (a 66% increase, not quite doubled from 2010 to 2012; P < .0001). Findings of the study indicate that the disaster had a significant impact on the local residents' (1) awareness of preparedness campaigns, (2) awareness of the need to be prepared, (3) willingness to become better prepared, and (4) possession of a disaster and emergency preparedness kit and its associated items.

The political ecology of disaster: an analysis of factors influencing U.S. tornado fatalities and injuries, 1998-2000.

Science.gov (United States)

Donner, William R

2007-08-01

This study examines casualties from tornadoes in the United States between the years 1998 and 2000. A political model of human ecology (POET) was used to explore how the environment, technology, and social inequality influence rates of fatalities and injuries in two models. Data were drawn from four sources: John Hart's Severe Plot v2.0, National Weather Service (NWS) Warning Verification data, Storm Prediction Center (SPC) watch data, and tract-level census data. Negative binomial regression was used to analyze the causes of tornado fatalities and injuries. Independent variables (following POET) are classified in the following manner: population, organization, environment, and technology. Rural population, population density, and household size correspond to population; racial minorities and deprivation represent social organization; tornado area represents environment; and tornado watches and warnings, as well as mobile homes, correspond to technology. Findings suggest a strong relationship between the size of a tornado path and both fatalities and injuries, whereas other measures related to technology, population, and organization produce significant yet mixed results. Census tracts having larger populations of rural residents was, of the nonenvironmental factors, the most conclusive regarding its effects across the two models. The outcomes of analysis, although not entirely supportive of the model presented in this study, suggest to some degree that demographic and social factors play a role in vulnerability to tornadoes.

Tornado risk analysis at Savannah River Plant using windspeed damage thresholds and single building strike frequencies

International Nuclear Information System (INIS)

Taylor, D.H.; McDonald, J.R.; Twisdale, L.A.

1985-01-01

Tornado risk analysis at the Savannah River Plant has taken a two pronged approach: (1) developing a catalogue of damage thresholds as a function of windspeed for processing buildings and other representative site structures; (2) developing a method of estimating, for each building, the probability of a tornado exceeding each damage threshold. Wind resistance of building construction at SRP varies widely depending on the function of the structure. It was recognized that all tornadoes do not necessarily seriously damage buildings, but the damage thresholds were unknown. In order to evaluate the safety of existing structures and properly design new structures, an analysis of tornado resistance was conducted by J.R. McDonald on each process building at SRP and other buildings by type. Damage estimates were catalogued for each Fujita class windspeed interval and windspeeds were catalogued as a function of increased levels of damage. Tornado single point and structure specific strike probabilities for the SRP site were determined by L.A. Twisdale using the TORRISK computer code. To calculate the structure specific strike probability, a correction factor is determined from a set of curves using building area and aspect ratio (length/width relative to north) as parameters. The structure specific probability is then the product of the correction factor and the point probability. The correction factor increases as a function of building size and windspeed. For large buildings (10 5 ft 2 ) and very intense storms (250 mph), the correction factor is equal to or greater than 4. The cumulative probability of a tornado striking any building type (process, personnel, etc.) was also calculated

Okla. Tornado Renews Debate on Storm Safety

Science.gov (United States)

Shah, Nirvi

2013-01-01

As soon as the winds that left seven students in Moore, Okla., dead last month had calmed, and more storms blew through the same area less than two weeks later, questions about the safety of schools in a region labeled Tornado Alley rose amid the rubble. While better design of new schools and thorough emergency training and practice may be in…

Investigation into the Formation, Structure, and Evolution of an EF4 Tornado in East China Using a High-Resolution Numerical Simulation

Science.gov (United States)

Yao, Dan; Xue, Haile; Yin, Jinfang; Sun, Jisong; Liang, Xudong; Guo, Jianping

2018-04-01

Devastating tornadoes in China have received growing attention in recent years, but little is known about their formation, structure, and evolution on the tornadic scale. Most of these tornadoes develop within the East Asian monsoon regime, in an environment quite different from tornadoes in the U.S. In this study, we used an idealized, highresolution (25-m grid spacing) numerical simulation to investigate the deadly EF4 (Enhanced Fujita scale category 4) tornado that occurred on 23 June 2016 and claimed 99 lives in Yancheng, Jiangsu Province. A tornadic supercell developed in the simulation that had striking similarities to radar observations. The violent tornado in Funing County was reproduced, exceeding EF4 (74 m s-1), consistent with the on-site damage survey. It was accompanied by a funnel cloud that extended to the surface, and exhibited a double-helix vorticity structure. The signal of tornado genesis was found first at the cloud base in the pressure perturbation field, and then developed both upward and downward in terms of maximum vertical velocity overlapping with the intense vertical vorticity centers. The tornado's demise was found to accompany strong downdrafts overlapping with the intense vorticity centers. One of the interesting findings of this work is that a violent surface vortex was able to be generated and maintained, even though the simulation employed a free-slip lower boundary condition. The success of this simulation, despite using an idealized numerical approach, provides a means to investigate more historical tornadoes in China.

Development of a design basis tornado and structural design criteria for Lawrence Livermore Laboratory's Site 300

International Nuclear Information System (INIS)

McDonald, J.R.; Minor, J.E.; Mehta, K.C.

1975-11-01

Criteria are prescribed and guidance is provided for professional personnel who are involved with the evaluation of existing buildings and facilities at Site 300 near Livermore, California to resist the possible effects of extreme winds and tornadoes. The development of parameters for the effects of tornadoes and extreme winds and guidelines for evaluation and design of structures are presented. The investigations conducted are summarized and the techniques used for arriving at the combined tornado and extreme wind risk model are discussed. The guidelines for structural design methods for calculating pressure distributions on walls and roofs of structures and methods for accommodating impact loads from missiles are also presented

Tornado missile simulation and design methodology. Volume 1: simulation methodology, design applications, and TORMIS computer code. Final report

International Nuclear Information System (INIS)

Twisdale, L.A.; Dunn, W.L.

1981-08-01

A probabilistic methodology has been developed to predict the probabilities of tornado-propelled missiles impacting and damaging nuclear power plant structures. Mathematical models of each event in the tornado missile hazard have been developed and sequenced to form an integrated, time-history simulation methodology. The models are data based where feasible. The data include documented records of tornado occurrence, field observations of missile transport, results of wind tunnel experiments, and missile impact tests. Probabilistic Monte Carlo techniques are used to estimate the risk probabilities. The methodology has been encoded in the TORMIS computer code to facilitate numerical analysis and plant-specific tornado missile probability assessments. Sensitivity analyses have been performed on both the individual models and the integrated methodology, and risk has been assessed for a hypothetical nuclear power plant design case study

Emotional Reactions of Rescue Workers Following a Tornado.

Science.gov (United States)

McCammon, Susan L.; And Others

Rescue and medical workers may be at risk for negative emotional experience following intervention efforts in disaster situations. To examine this possibility, 120 rescue and hospital personnel responded to a survey of their emotional reactions and coping behaviors 3 months after a devastating tornado. Twenty-eight subjects had been involved in…

Necrotizing cutaneous mucormycosis after a tornado in Joplin, Missouri, in 2011.

Science.gov (United States)

Neblett Fanfair, Robyn; Benedict, Kaitlin; Bos, John; Bennett, Sarah D; Lo, Yi-Chun; Adebanjo, Tolu; Etienne, Kizee; Deak, Eszter; Derado, Gordana; Shieh, Wun-Ju; Drew, Clifton; Zaki, Sherif; Sugerman, David; Gade, Lalitha; Thompson, Elizabeth H; Sutton, Deanna A; Engelthaler, David M; Schupp, James M; Brandt, Mary E; Harris, Julie R; Lockhart, Shawn R; Turabelidze, George; Park, Benjamin J

2012-12-06

Mucormycosis is a fungal infection caused by environmentally acquired molds. We investigated a cluster of cases of cutaneous mucormycosis among persons injured during the May 22, 2011, tornado in Joplin, Missouri. We defined a case as a soft-tissue infection in a person injured during the tornado, with evidence of a mucormycete on culture or immunohistochemical testing plus DNA sequencing. We conducted a case-control study by reviewing medical records and conducting interviews with case patients and hospitalized controls. DNA sequencing and whole-genome sequencing were performed on clinical specimens to identify species and assess strain-level differences, respectively. A total of 13 case patients were identified, 5 of whom (38%) died. The patients had a median of 5 wounds (range, 1 to 7); 11 patients (85%) had at least one fracture, 9 (69%) had blunt trauma, and 5 (38%) had penetrating trauma. All case patients had been located in the zone that sustained the most severe damage during the tornado. On multivariate analysis, infection was associated with penetrating trauma (adjusted odds ratio for case patients vs. controls, 8.8; 95% confidence interval [CI], 1.1 to 69.2) and an increased number of wounds (adjusted odds ratio, 2.0 for each additional wound; 95% CI, 1.2 to 3.2). Sequencing of the D1-D2 region of the 28S ribosomal DNA yielded Apophysomyces trapeziformis in all 13 case patients. Whole-genome sequencing showed that the apophysomyces isolates were four separate strains. We report a cluster of cases of cutaneous mucormycosis among Joplin tornado survivors that were associated with substantial morbidity and mortality. Increased awareness of fungi as a cause of necrotizing soft-tissue infections after a natural disaster is warranted.

Unmanned Aerial Vehicle Systems for Disaster Relief: Tornado Alley

Science.gov (United States)

DeBusk, Wesley M.

2009-01-01

Unmanned aerial vehicle systems are currently in limited use for public service missions worldwide. Development of civil unmanned technology in the United States currently lags behind military unmanned technology development in part because of unresolved regulatory and technological issues. Civil unmanned aerial vehicle systems have potential to augment disaster relief and emergency response efforts. Optimal design of aerial systems for such applications will lead to unmanned vehicles which provide maximum potentiality for relief and emergency response while accounting for public safety concerns and regulatory requirements. A case study is presented that demonstrates application of a civil unmanned system to a disaster relief mission with the intent on saving lives. The concept utilizes unmanned aircraft to obtain advanced warning and damage assessments for tornados and severe thunderstorms. Overview of a tornado watch mission architecture as well as commentary on risk, cost, need for, and design tradeoffs for unmanned aerial systems are provided.

Using Satellite Imagery to Identify Tornado Damage Tracks and Recovery from the April 27, 2011 Severe Weather Outbreak

Science.gov (United States)

Cole, Tony A.; Molthan, Andrew L.; Bell, Jordan R.

2014-01-01

Emergency response to natural disasters requires coordination between multiple local, state, and federal agencies. Single, relatively weak tornado events may require comparatively simple response efforts; but larger "outbreak" events with multiple strong, long-track tornadoes can benefit from additional tools to help expedite these efforts. Meteorologists from NOAA's National Weather Service conduct field surveys to map tornado tracks, assess damage, and determine the tornado intensity following each event. Moderate and high resolution satellite imagery can support these surveys by providing a high-level view of the affected areas. Satellite imagery could then be used to target areas for immediate survey or to corroborate the results of the survey after it is completed. In this study, the feasibility of using satellite imagery to identify tornado damage tracks was determined by comparing the characteristics of tracks observed from low-earth orbit to tracks assessed during the official NWS storm survey process. Of the 68 NWS confirmed centerlines, 24 tracks (35.3%) could be distinguished from other surface features using satellite imagery. Within each EF category, 0% of EF-0, 3% of EF-1, 50% of EF-2, 77.7% of EF-3, 87.5% of EF-4 and 100% of EF-5 tornadoes were detected. It was shown that satellite data can be used to identify tornado damage tracks in MODIS and ASTER NDVI imagery, where damage to vegetation creates a sharp drop in values though the minimum EF-category which can be detected is dependent upon the type of sensor used and underlying vegetation. Near-real time data from moderate resolution sensors compare favorably to field surveys after the event and suggest that the data can provide some value in the assessment process.

Alabama Disasters: Leveraging NASA EOS to Explore the Environmental and Economic Impact of the April 27 Tornado Outbreak

Science.gov (United States)

Herdy, Claire; Luvall, Jeff

2012-01-01

The disastrous tornado outbreak in Alabama on April 27, 2011 greatly impacted the economy of the state. On record, the tornado outbreak was the second deadliest tornado outbreak in U.S. When considering the agricultural and value-added activities such as food and timber processing, farm inputs, manufacturing, transportation, and retail sales, the dollar value of Alabama agribusiness annually exceeds $40 billion (NASS, 2011). This research aims to examine how the timber and agriculture damage affected the state economy of Alabama and will be used to aid in long-term economic recovery. ASTER imagery was used along with ground-truthed NASS (National Agriculture Statistics Service) crop location records to verify the economic impact tornadoes had on the agricultural economy of the state. This swath damage can be calculated by correlating tornado path with NASS statistics on crop yield, precisely showing the fields affected and dollars lost to this disaster. Not only can this be executed manually using ENVI and ArcGIS, but also through the use of Python, a programming language that has the ability to automate the process, creating a product for initial damage assessment.

77 FR 4389 - In the Matter of Tornado Gold International Corp., Twin Faces East Entertainment Corp., Universal...

Science.gov (United States)

2012-01-27

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] In the Matter of Tornado Gold International Corp., Twin Faces East Entertainment Corp., Universal Ice Blast, Inc., US Farms, Inc., US Microbics... concerning the securities of Tornado Gold International Corp. because it has not filed any periodic reports...

Development of a tornado safe room door from wood Products: door design and impact testing

Science.gov (United States)

Robert H. Falk; James J. Bridwell

2016-01-01

In this study, a tornado safe room door built from wood products and steel sheeting was developed and impact-tested according to tornado safe room standards. Results indicate that an door constructed from as few as two sheets of 23/32-in. (18.26-mm) construction-grade plywood and overlaid with 18-gauge (0.05-in.- (1.27- mm-) thick) steel can pass the required impact...

Full-scale Tornado-missile impact tests

International Nuclear Information System (INIS)

1976-04-01

Initial tests with four types of hypothetical tornado-borne missiles impacting reinforced concrete panels have been completed. Panel thicknesses are typical of walls in nuclear power facilities. In the seven tests, the missiles were rocket propelled to velocities currently postulated as being attainable by debris in tornadoes. The objective of the 18-test program is to ascertain the vulnerability of test panels to penetration and backface scabbing. The four missile types being tested are: a 1500-pound 35-foot long utility pole, an 8-pound 1-inch Grade 60 reinforcing bar, a 78-pound 3-inch Schedule 40 pipe, and a 743-pound 12-inch Schedule 40 pipe. The test panels are 12, 18, and 24 inches thick with 15 by 15 foot free spans. They were constructed to current minimum ACI standards: 3000 psi design strength (actual strength about 3600 psi) and 0.2 percent reinforcing steel area each way, each face (actual area is about 0.27 percent with bars on 12-inch centers). The 12-inch pipe has been identified as the critical missile for design of nuclear facility walls under currently specified impact conditions. The utility poles splintered upon impact causing virtually no impact damage, and the 3-inch pipe and 1-inch rebar were comparatively ineffectual because of their light weight

Systematic Study of the Failure of a Light-Frame Wood Roof in a Tornado

OpenAIRE

Lindt, John van de; Amini, Mohammad; Standohar-Alfano, Christine; Dao, Thang

2012-01-01

Tornadoes are a particularly devastating natural hazard that affect communities across the United States, particularly the Midwest and South. They are unique from an engineering point-of-view due to their very low probability of occurrence but often highly destructive consequences. The 2011 season was particularly devastating to the Southeastern portion of the U.S. This paper presents a single case study of a 2012 tornado that struck a single large rural light-frame wood house with an unconve...

Full-scale tornado-missile impact tests

International Nuclear Information System (INIS)

Stephenson, A.E.; Sliter, G.E.; Burdette, E.G.

1978-01-01

Full-scale poles, pipes, and rods, representing postulated tornado-borne missiles, were rocket-propelled into reinforced concrete panels with thicknesses typical of walls and roofs in the auxillary buildings of nuclear power plants. Data from the 18 tests can be used directly for structural design or for validating design and analysis techniques. The test panels, constructed with 3000-psi design strength concrete and minimum allowable reinforcement, were 12, 18 and 24 in. thick with 15 X 15-ft unsupported spans. (Auth.)

Ground beetle (Coleoptera, Carabidae) assemblages inhabiting Scots pine stands of Puszcza Piska Forest: six-year responses to a tornado impact.

Science.gov (United States)

Skłodowski, Jarosław; Garbalińska, Paulina

2011-01-01

Ground beetle assemblages were studied during 2003-08 in the Pisz Forest by comparing stands disturbed by a tornado to undisturbed control stands. The following exploratory questions were put forward. (1) How do the carabid assemblages change during six years following the tornado impact? (2) Does the carabid assemblage recovery begin during the six first post-tornado years? To assess the state of carabid assemblages we used two indices: the MIB (Mean Individual Biomass) and the SPC (Sum of Progressive Characteristics). Carabid assemblages in the disturbed and in the control stands, as expressed by these two indices, were compared using the length of a regression distance (sample distance in a MIB:SPC coordinate system). A cluster analysis revealed that the assemblages of the disturbed and the control stands were different. The tornado-impacted stands produced lower carabid catch rates, but species richness was significantly higher there than in the control stands. They hosted lower proportions of individuals of European species, of large zoophages, and of forest and brachypterous species, than the control stands. The observed reduction in SPC and MIB, and an increase in the regression distances may indicate that the carabid assemblages had not started to recover from the tornado-caused disturbance. Carabid assemblages apparently responded to the tornado in two steps. Firstly, the first three years were characterized by moderate decreases of index values. Secondly, from the fourth to the sixth year after the tornado, many observed changes became magnified. We did not observe clear signals of the recovery of forest carabid assemblages during the six follow-up years.

Mental Health Among Adolescents Exposed to a Tornado: The Influence of Social Support and Its Interactions With Sociodemographic Characteristics and Disaster Exposure.

Science.gov (United States)

Paul, Lisa A; Felton, Julia W; Adams, Zachary W; Welsh, Kyleen; Miller, Stephanie; Ruggiero, Kenneth J

2015-06-01

Approximately 25% of youths experience a natural disaster and many experience disaster-related distress, including symptoms of posttraumatic stress disorder (PTSD) and depression. This study contributes to the literature by examining PTSD and depressive symptoms among 2,000 adolescents (50.9% female, 70.5% White) assessed after exposure to tornadoes in 2011. The authors hypothesized that greater tornado exposure, female sex, and younger age would be associated with distress, and that social support would interact with these associations. Analyses showed that PTSD symptoms were associated with lower levels of social support (β = -.28, p tornado exposure (β = .14, p tornado exposure, sex, and social support (β = -.06, p = .017). For boys, the influence of tornado exposure on PTSD symptoms increased as social support decreased. Regardless of level of tornado exposure, low social support was related to PTSD symptoms for girls; depressive symptom results were similar. These findings were generally consistent with the literature and provide guidance for intervention development focused on strengthening social support at the individual, family, and community levels. © 2015 International Society for Traumatic Stress Studies.

Tornado type closed magnetic trap for an ECR source

CERN Document Server

Abramova, K B; Voronin, A V; Zorin, V G

1999-01-01

We propose to use a Tornado type closed magnetic trap for creation of a source of mul-ticharged ions with plasma heating by microwave radiation. Plasma loss in closed traps is deter-mined by diffusion across the magnetic field, which increases substantially plasma confinement time as compared to the classical mirror trap [1]. We propose to extract ions with the aid of additional coils which partially destroy the closed structure of the magnetic lines in the trap, but don not influence the total confinement time. This allows for producing a controlled plasma flux that depends on the magnetic field of the additional coil. The Tornado trap also possesses merits such as an opportunity to produce high magnetic fields up to 3 T, which makes possible heating and confinement of plasma with a high density of electrons; plasma stability to magneto-hydrodynamic perturbations because the magnetic field structure corresponds to the "min B" configuration; and relatively low costs. All estimates and calculations were carrie...

Innovative probabilistic risk assessment applications: barrier impairments and fracture toughness. 2. Demolition Debris and Tornado Missile Hazard During Decommissioning

International Nuclear Information System (INIS)

Calhoun, David; Shepherd, Stephen

2001-01-01

During their operating lives, nuclear power plants typically maintain a high level of control over the amount of debris that is allowed to accumulate at the plant site. Although primarily intended to reduce the potential for fire damage, some plants also rely on these controls to limit the damage that could be caused during a tornado from missiles generated from loose debris. Demolition work associated with power plant decommissioning inevitably increases the quantity of debris. When bulk commodities such as piping and electrical distribution components are demolished, they are subject to various staging, handling, and storage processes before they can be released from the site. The demolition of plant structures dramatically increases the quantity of loose steel and concrete debris. For the foreseeable future, all plants that undertake decommissioning will have spent-fuel assemblies present on the plant site during the demolition project whether the spent fuel remains stored in a spent-fuel pool or is transferred to an independent spent-fuel storage installation (ISFSI). Under present regulations, protection from tornado missiles would be required for both types of spent-fuel storage. In addition, a small proportion of decommissioning plants will have operating units in close proximity. Licensing commitments for tornado missile protection may mandate controls on the production or storage of demolition debris. This paper presents a case study of the San Onofre Nuclear Generating Station (Fig. 1). Tornado missile protection licensing commitments from three types of facilities will be in force during the decommissioning of San Onofre Unit 1 (Unit 1): 1. Unit 1, under a possession-only license; 2. an ISFSI that will eventually store spent fuel from Unit 1; 3. San Onofre Operating Unit 2 (Unit 2) and San Onofre Operating Unit 3 (Unit 3). Together, these three facilities illustrate the range of impacts that licensing commitments designed for tornado protection may

Coupling of ionosphere and troposphere during the occurrence of isolated tornadoes on November 20, 1973

Science.gov (United States)

Hung, R. J.; Phan, T.; Smith, R. E.

1979-01-01

The paper examines the coupling between the ionosphere and the troposphere during time periods with isolated tornadoes on the stormy day of November 20, 1973. Observations are made with a high-frequency CW Doppler array system, in which radio receivers located at a central site monitored signals transmitted from three independent remote sites on three sets of frequencies (4.0125, 4.759, 5.734 MHz) and reflected off the ionosphere approximately halfway between the transmitter and receiver sites. It is shown that the sources of the gravity waves associated with tornadoes are always on the squall lines and near the tornado touchdown locations, and that analyses of ionospheric Doppler sounder observations of medium-scale gravity waves can contribute to the understanding of the coupling between the ionosphere and the troposphere during periods of severe storm activity.

Tornadoes, Florida's Miami Tequesta Site, Memphremagog, America's Stonehenge, A.S., Mexico/Rumford ME, and Some Applied Physics.

Science.gov (United States)

Mc Leod, Edward M.; Mc Leod, David M.; Mc Leod, Roger D.

2002-04-01

Hay or dust devils, firestorm "twisters", waterspouts, and Fujita's entire range of F1 to F5 tornadoes have a completely explainable common source. These can exist only where the earth's electromagnetic field, EMF, makes loops, or their associated breaks and reorganizations, like those observable at sunspots. Fujita's F1 tornadoes require ionized air in modest thunderclouds with ordinary up- or downdrafts. The equivalent charge-velocity vector then is in "cross-product" with the "hypothesized," but detectable, "tubes" of magnetic field. This creates the familiar vortex that the ionic flow forms, which initially emerges somewhat horizontally from the thundercloud; this can work its way down the loop to touchdown. Fujita's F2 and F3 tornadoes may need the intersection of an ionized jet stream with a high-level EMF loop. The F4 and F5 variety possibly require the combined effects of vertical storm drafts and a jet stream to reach rotational speeds of 318 mph. We have been at EMF sites detectable by blue-light phenomena, A.S. and tornado sites visually qualify.

Conditional probability of the tornado missile impact given a tornado occurrence

International Nuclear Information System (INIS)

Goodman, J.; Koch, J.E.

1982-01-01

Using an approach based on statistical mechanics, an expression for the probability of the first missile strike is developed. The expression depends on two generic parameters (injection probability eta(F) and height distribution psi(Z,F)), which are developed in this study, and one plant specific parameter (number of potential missiles N/sub p/). The expression for the joint probability of simultaneous impact of muitiple targets is also developed. This espression is applicable to calculation of the probability of common cause failure due to tornado missiles. It is shown that the probability of the first missile strike can be determined using a uniform missile distribution model. It is also shown that the conditional probability of the second strike, given the first, is underestimated by the uniform model. The probability of the second strike is greatly increased if the missiles are in clusters large enough to cover both targets

Permanent record. Electronic records aid in the aftermath of Joplin tornado.

Science.gov (United States)

Russell, Matthew

2011-09-01

When a tornado struck St. John's Regional Medical Center in May 2011, its patient records were stored in a newly launched electronic health record system, helping prevent a bad situation from being worse.

Development of margin assessment methodology of decay heat removal function against external hazards. (2) Tornado PRA methodology

International Nuclear Information System (INIS)

Nishino, Hiroyuki; Kurisaka, Kenichi; Yamano, Hidemasa

2014-01-01

Probabilistic Risk Assessment (PRA) for external events has been recognized as an important safety assessment method after the TEPCO's Fukushima Daiichi nuclear power station accident. The PRA should be performed not only for earthquake and tsunami which are especially key events in Japan, but also the PRA methodology should be developed for the other external hazards (e.g. tornado). In this study, the methodology was developed for Sodium-cooled Fast Reactors paying attention to that the ambient air is their final heat sink for removing decay heat under accident conditions. First, tornado hazard curve was estimated by using data recorded in Japan. Second, important structures and components for decay heat removal were identified and an event tree resulting in core damage was developed in terms of wind load and missiles (i.e. steel pipes, boards and cars) caused by a tornado. Main damage cause for important structures and components is the missiles and the tornado missiles that can reach those components and structures placed on high elevations were identified, and the failure probabilities of the components and structures against the tornado missiles were calculated as a product of two probabilities: i.e., a probability for the missiles to enter the intake or outtake in the decay heat removal system, and a probability of failure caused by the missile impacts. Finally, the event tree was quantified. As a result, the core damage frequency was enough lower than 10 -10 /ry. (author)

Development of a design basis tornado and structural design criteria for the Nevada Test Site, Nevada. Final report

International Nuclear Information System (INIS)

McDonald, J.R.; Minor, J.E.; Mehta, K.C.

1975-06-01

In order to evaluate the ability of critical facilities at the Nevada Test Site to withstand the possible damaging effects of extreme winds and tornadoes, parameters for the effects of tornadoes and extreme winds and structural design criteria for the design and evaluation of structures were developed. The meteorological investigations conducted are summarized, and techniques used for developing the combined tornado and extreme wind risk model are discussed. The guidelines for structural design include methods for calculating pressure distributions on walls and roofs of structures and methods for accommodating impact loads from wind-driven missiles. Calculations for determining the design loads for an example structure are included

Hawkmoth flight performance in tornado-like whirlwind vortices.

Science.gov (United States)

Ortega-Jimenez, Victor Manuel; Mittal, Rajat; Hedrick, Tyson L

2014-06-01

Vertical vortex systems such as tornadoes dramatically affect the flight control and stability of aircraft. However, the control implications of smaller scale vertically oriented vortex systems for small fliers such as animals or micro-air vehicles are unknown. Here we examined the flapping kinematics and body dynamics of hawkmoths performing hovering flights (controls) and maintaining position in three different whirlwind intensities with transverse horizontal velocities of 0.7, 0.9 and 1.2 m s(-1), respectively, generated in a vortex chamber. The average and standard deviation of yaw and pitch were respectively increased and reduced in comparison with hovering flights. Average roll orientation was unchanged in whirlwind flights but was more variable from wingbeat to wingbeat than in hovering. Flapping frequency remained unchanged. Wingbeat amplitude was lower and the average stroke plane angle was higher. Asymmetry was found in the angle of attack between right and left wings during both downstroke and upstroke at medium and high vortex intensities. Thus, hawkmoth flight control in tornado-like vortices is achieved by a suite of asymmetric and symmetric changes to wingbeat amplitude, stroke plane angle and principally angle of attack.

Hawkmoth flight performance in tornado-like whirlwind vortices

International Nuclear Information System (INIS)

Ortega-Jimenez, Victor Manuel; Hedrick, Tyson L; Mittal, Rajat

2014-01-01

Vertical vortex systems such as tornadoes dramatically affect the flight control and stability of aircraft. However, the control implications of smaller scale vertically oriented vortex systems for small fliers such as animals or micro-air vehicles are unknown. Here we examined the flapping kinematics and body dynamics of hawkmoths performing hovering flights (controls) and maintaining position in three different whirlwind intensities with transverse horizontal velocities of 0.7, 0.9 and 1.2 m s −1 , respectively, generated in a vortex chamber. The average and standard deviation of yaw and pitch were respectively increased and reduced in comparison with hovering flights. Average roll orientation was unchanged in whirlwind flights but was more variable from wingbeat to wingbeat than in hovering. Flapping frequency remained unchanged. Wingbeat amplitude was lower and the average stroke plane angle was higher. Asymmetry was found in the angle of attack between right and left wings during both downstroke and upstroke at medium and high vortex intensities. Thus, hawkmoth flight control in tornado-like vortices is achieved by a suite of asymmetric and symmetric changes to wingbeat amplitude, stroke plane angle and principally angle of attack. (papers)

Pipe/duct system design for tornado missile impact loads

Energy Technology Data Exchange (ETDEWEB)

Li, J.; Wang, S.; Johnson, W., E-mail: whjohnso@bechtel.com

2014-04-01

For nuclear power plant life extension projects, it may be convenient and in some instances necessary to locate safety-related steel ducts and pipes outside of the main structures, exposing them to extreme environmental loads such as tornado missile impact. Examples of this application include emergency firewater lines and Control Room vent ducts. A typical exposed commodity run could be comprised of a rectangular or circular cross-section with horizontal and vertical segments supported at variable spans off of roof and wall panels, respectively. Efficient and economical design of such a tornado-impacted duct or pipe system, consisting of the commodity and its supports, must exploit all of the system's capability to absorb the impact energy by deforming plastically to the fullest extent allowable. Energy can be absorbed locally in the vicinity of impact on the commodity, globally through rotation at flexural plastic hinges, and through yielding of the supports. In this paper a simplified NDOF lumped parameter nonlinear analysis methodology is presented and applied to the coupled commodity/support system subjected to tornado impulse loading. The analysis methodology is confirmed using a detailed ANSYS nonlinear finite element model. Optimization of the initial trial design is achieved by progressively decreasing the support resistances, while monitoring the response ductilities throughout the system. Evaluation methodologies are provided for the four types of plastic deformation responses which occur in the system: local response in the immediate vicinity of impact, flexural and membrane response of the sidewall out to one or two times the commodity depth beyond the point of impact, global response of the commodity as a beam spanning between supports, and the shear and flexural response of support. The inelastic responses are evaluated against AISC N690 acceptance criteria (ANSI, 2006), supplemented as appropriate by triaxiality considerations for inelastic

Structural performance of HEPA filters under simulated tornado conditions

International Nuclear Information System (INIS)

Horak, H.L.; Gregory, W.S.; Ricketts, C.I.; Smith, P.R.

1982-02-01

This report contains the results of structural tests to determine the response of High Efficiency Particulate Air filters to simulated tornado conditions. The data include the structural limits of the filters, their resistance at high flow rates, and the effects of filter design features and tornado parameters. Considering all the filters tested, the mean break pressure or structural limit was found to be 2.35 pse (16.2 kPa). The maximum value was 2.87 psi (19.8 kPa), and the low value found was 1.31 psi (9.0 kPa). The type of failure was usually a medium break of the downstream filter fold. The type of filters that were evaluated were nuclear grade with design flow rates of 1000 cfm (0.472 m 3 /s), standard separators, and folded medium design. The parameters evaluated that are characteristic of the filter included manufacturer, separator type, faceguards, pack tightness, and aerosol loading. Manufacturer and medium properties were found to have a large effect on the structural limits

Individual relocation decisions after tornadoes: a multi-level analysis.

Science.gov (United States)

Cong, Zhen; Nejat, Ali; Liang, Daan; Pei, Yaolin; Javid, Roxana J

2018-04-01

This study examines how multi-level factors affected individuals' relocation decisions after EF4 and EF5 (Enhanced Fujita Tornado Intensity Scale) tornadoes struck the United States in 2013. A telephone survey was conducted with 536 respondents, including oversampled older adults, one year after these two disaster events. Respondents' addresses were used to associate individual information with block group-level variables recorded by the American Community Survey. Logistic regression revealed that residential damage and homeownership are important predictors of relocation. There was also significant interaction between these two variables, indicating less difference between homeowners and renters at higher damage levels. Homeownership diminished the likelihood of relocation among younger respondents. Random effects logistic regression found that the percentage of homeownership and of higher income households in the community buffered the effect of damage on relocation; the percentage of older adults reduced the likelihood of this group relocating. The findings are assessed from the standpoint of age difference, policy implications, and social capital and vulnerability. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

Analytic studies on satellite detection of severe, two-cell tornadoes

Science.gov (United States)

Carrier, G. F.; Dergarabedian, P.; Fendell, F. E.

1979-01-01

From funnel-cloud-length interpretation, the severe tornado is characterized by peak swirl speed relative to the axis of rotation of about 90 m/s. Thermohydrodynamic achievement of the pressure deficit from ambient necessary to sustain such swirls requires that a dry, compressionally heated, non-rotating downdraft of initially tropopause-level air lie within an annulus of rapidly swirling, originally low-level air ascending on a near-moist-adiabatic locus of thermodynamic states. The two-cell structure furnishes an observable parameter possibly accessible to a passively instrumented, geosynchronous meteorological satellite with mesoscale resolution, for early detection of a severe tornado. Accordingly, the low-level turnaround region, in which the surface inflow layer separates to become a free ascending layer and for which inviscid modeling suffices, is examined quantitatively. Preliminary results indicate that swirl overshoot, i.e., swirl speeds in the turnaround region in excess of the maximum achieved in the potential vortex, is modest.

Barrier design for tornado-generated missiles

International Nuclear Information System (INIS)

Kar, A.K.

1977-01-01

Nuclear power plant facilities and many other structures need protection against missiles generated by tornados and explosions. The missile impacts result in both local and overall effects on barriers or targets. The local effects are characterized by penetration, perforation and backface spalling or scabbing of the target material. The overall effects of missile impact on structural stability are commonly evaluated in terms of the flexural and shear behaviour of the target. Empirical formulas are presented to determine the local effects on concrete and steel barriers. Procedures are given for determining the design loads for overall effects. Design methods are described. (Auth.)

Barrier design for tornado-generated missiles

International Nuclear Information System (INIS)

Kar, A.K.

1977-01-01

Nuclear powerplant facilities and many other structures need protection against missiles generated by tornadoes and explosions. The missile impacts result in both local and overall effects on barriers or targets. The local effects are characterized by penetration, perforation, and backface spalling or scabbing of the target material. The overall effects of missile impact on structural stability are commonly evaluated in terms of the flexural and shear behavior of the target. Empirical formulas are presented to determine the local effects on concrete and steel barriers. Procedures are given for determining the design loads for overall effects. Design methods are described

Tornado damage at the Grand Gulf, Mississippi nuclear power plant site: aerial and ground surveys

International Nuclear Information System (INIS)

Fujita, T.T.; McDonald, J.R.

1978-05-01

A tornado struck the Grand Gulf nuclear power generating station, Port Gibson, Mississippi, about 11:30 p.m. on April 17, 1978. Storm damage investigators from the University of Chicago and Texas Tech University were dispatched to survey the damage. The meteorological situation that spawned the Grand Gulf tornado and seven others in the area is discussed. Aerial surveys of the entire damage path and detailed surveys of the plant site are presented. An engineering evaluation of the damage is also presented based primarily on information gained from detailed ground surveys

Automated Tracking of Tornado-Producing Mesoscale Convective Systems in the United States

Science.gov (United States)

Kuo, K.; Hong, Y.; Clune, T. L.

2011-12-01

The great majority of Earth Science events are studied using "snap-shot" observations in time, mainly due to the scarcity of observations with dense temporal coverage and the lack of robust methods amenable to connecting the "snap shots". To enable the studies of these events in the four-dimensional (4D) spatiotemporal space and to demonstrate the utility of this capability, we have applied the neighbor enclosed area tracking (NEAT) method of Inatsu (2009) to three years of high-resolution (in both time and space) NEXRAD-derived and rain-gauge-corrected QE2 precipitation observations and GOES satellite Rapid Scan Operation imagery to track tornado-producing mesoscale convective systems (MCS's). We combine information from the databases of the Tornado History Project (which provides tornado occurrence and trajectory) and the NWS Watch/Warning Archive (which provides severe weather watch/warning locations) to obtain initial estimate of the time and location of a tornado-producing MCS. The NEAT algorithm is then applied to QE2 and GOES data, both forward and backward in time, to identify the entire system as one integral entity from its inception to its eventual dissipation in the 4D spatiotemporal space. For each system so identified, we extract its morphological/structural parameters, such as perimeter length, area, and orientation, from each of the snap shots in time. We also record physical parameters such as minimum and maximum precipitation rates. In addition, we perform areal integral on the precipitation rate field, which in turn enables time integral for the entire MCS throughout its lifecycle to obtain an estimate of the system's precipitation production. We can extend this proof-of-concept prototype to other precipitation producing severe weather events, such as blizzards. Furthermore, the spatiotemporal data collected may be used to discover other data, such as satellite remote sensing observations and model analyses/simulations, which can then be combined

Assessing Middle School and College Students' Conceptions About Wind, Fog, and Tornadoes

Science.gov (United States)

Polito, E.; Monteverdi, J. P.; Garcia, O.; Tanner, K. D.

2008-12-01

Meteorological content is presented in K-12 educational standards and in university general education courses, yet little research has been done to explore how students conceptualize weather phenomena. This investigation probes the understanding of students at three cognitive levels-6th grade earth science students, university non-meteorology majors, and meteorology major students-of three meteorological phenomena-wind, fog, and tornadoes. All students were enrolled in schools in San Francisco, CA. The meteorological content chosen for this project-wind, fog, and tornadoes-was deliberate. Wind is a fundamental process on our planet, and has the potential to cause great damage. Students have direct experience with wind on a daily basis. Fog is a dominant feature of San Francisco climatology, and a familiar phenomenon to students living in our region. Tornadoes are associated with devastating winds and represent a destructive weather phenomenon that students only experience indirectly through movies representations and other media outlets. The phases consisted of (a) a fifteen-question survey, (b) written essay assessments, and (c) videotaped interviews. Phase I, a weather survey, was given to the entire population (65 middle school students, 50 university non-meteorology majors, and 10 university meteorology majors) and consisted of 10-15 challenge statements. Challenge statements assert a common misconception or truism and ask the students to rank their level of agreement on a 4-point Likert scale (strongly agree, agree, disagree, strongly disagree). Phase II presented the students a subset of statements and questions, and they were given 5 minutes to explain why they chose their response. To quantify the resulting qualitative data, the written essay assessments were scored using a developed conceptual rubric by multiple observers, using inter-observer reliability to measure agreement in scoring. The results from this phase helped to structure the interview

Epidemiology of tornado destruction in rural northern Bangladesh: risk factors for death and injury.

Science.gov (United States)

Sugimoto, Jonathan D; Labrique, Alain B; Ahmad, Salahuddin; Rashid, Mahbubur; Shamim, Abu Ahmed; Ullah, Barkat; Klemm, Rolf D W; Christian, Parul; West, Keith P

2011-04-01

The epidemiology of tornado-related disasters in the developing world is poorly understood. An August 2005 post-tornado cohort study in rural Bangladesh identified elevated levels of death and injury among the elderly (≥ 60 years of age) (adjusted odds ratio (AOR) = 8.9 (95 per cent confidence interval (CI): 3.9-20.2) and AOR = 1.6 (95 per cent CI: 1.4-1.8), respectively), as compared to 15-24 year-olds, and among those outdoors versus indoors during the tornado (AOR = 10.4 (95 per cent CI: 5.5-19.9) and AOR = 6.6 (95 per cent CI: 5.8-7.5), respectively). Females were 1.24 times (95 per cent CI: 1.15-1.33) more likely to be injured than males. Elevated risk of injury was significantly associated with structural damage to the house and tin construction materials. Seeking treatment was protective against death among the injured, odds ratio = 0.08 (95 per cent CI: 0.03-0.21). Further research is needed to develop injury prevention strategies and to address disparities in risk between age groups and between men and women. © 2011 The Author(s). Disasters © Overseas Development Institute, 2011.

Wind field and trajectory models for tornado-propelled objects

International Nuclear Information System (INIS)

Anon

1978-01-01

This report contains the results of the second phase of a research program which has as its objective the development of a mathematical model to predict the trajectory of tornado-borne objects postulated to be in the vicinity of nuclear power plants. An improved tornado wind field model satisfies the no-slip ground boundary condition of fluid mechanics and includes the functional dependence of eddy viscosity with altitude. Sub-scale wind tunnel data are obtained for all of the missiles currently specified for nuclear plant design. Confirmatory full-scale data are obtained for a 12-inch pipe and automobile. The original six-degree-of-freedom trajectory model is modified to include the improved wind field and increased capability as to body shapes and inertial characteristics that can be handled. The improved trajectory model is used to calculate maximum credible speeds, which for all of the heavy missiles are considerably less than those currently specified for design. Equivalent coefficients for use in three-degree-of-freedom models are developed and the sensitivity of range and speed to various trajectory parameters for the 12-inch diameter pipe is examined

Twitter as a Potential Disaster Risk Reduction Tool. Part II: Descriptive Analysis of Identified Twitter Activity during the 2013 Hattiesburg F4 Tornado.

Science.gov (United States)

Cooper, Guy Paul; Yeager, Violet; Burkle, Frederick M; Subbarao, Italo

2015-06-29

This article describes a novel triangulation methodological approach for identifying twitter activity of regional active twitter users during the 2013 Hattiesburg EF-4 Tornado. A data extraction and geographically centered filtration approach was utilized to generate Twitter data for 48 hrs pre- and post-Tornado. The data was further validated using six sigma approach utilizing GPS data. The regional analysis revealed a total of 81,441 tweets, 10,646 Twitter users, 27,309 retweets and 2637 tweets with GPS coordinates. Twitter tweet activity increased 5 fold during the response to the Hattiesburg Tornado.  Retweeting activity increased 2.2 fold. Tweets with a hashtag increased 1.4 fold. Twitter was an effective disaster risk reduction tool for the Hattiesburg EF-4 Tornado 2013.

Mental Health Among Adolescents Exposed to a Tornado: The Influence of Social Support and its Interactions with Socio-Demographic Characteristics and Disaster Exposure

Science.gov (United States)

Paul, Lisa A.; Felton, Julia W.; Adams, Zachary W.; Welsh, Kyleen; Miller, Stephanie; Ruggiero, Kenneth J.

2015-01-01

Approximately 25% of youths experience a natural disaster and many experience disaster-related distress, including symptoms of posttraumatic stress disorder (PTSD) and depression. This study contributes to the literature by examining PTSD and depressive symptoms among 2,000 adolescents (50.9% female, 70.5% White) assessed after exposure to tornadoes in 2011. The authors hypothesized that greater tornado exposure, female sex, and younger age would be associated with distress, and that social support would interact with these associations. Analyses showed that PTSD symptoms were predicted by lower levels of social support (β = −.28, p tornado exposure (β = .14, ptornado exposure, sex, and social support (β = −.06, p = .017). For boys, the influence of tornado exposure on PTSD symptoms increased as social support decreased. Regardless of level of tornado exposure, low social support was related to PTSD symptoms for girls; depressive symptom results were similar. These findings are generally consistent with the literature and provide guidance for intervention development focused on strengthening social support at the individual, family, and community levels. PMID:26031997

The tornado history of the Czech Lands, AD 1119–2010

Czech Academy of Sciences Publication Activity Database

Brázdil, Rudolf; Chromá, Kateřina; Dobrovolný, Petr; Černoch, Z.

2012-01-01

Roč. 118, NOV 2012 (2012), s. 193-204 ISSN 0169-8095 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Keywords : Tornado * Spatio-temporal fluctuations * Impacts * Documentary data * Czech Lands Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.200, year: 2012

Study of the effects of a tornado on a nuclear plant(from the point of view of civil engineering)

International Nuclear Information System (INIS)

Melendro, J.

2010-01-01

is to analyze the applicability of Regulatory Guide 1.76 d esign basis Tornado and Tornado Missiles for Nuclear Power Plants , assessing the guide / standard compliance of a nuclear facility with respect to it, identifying the actions required for the compliance if applicable and valuation, with engineering judgment, the benefits for the plant would total or partial implantation of the guide.

An observational study of the 7 September 2005 Barcelona tornado outbreak

Directory of Open Access Journals (Sweden)

J. Bech

2007-01-01

Full Text Available This paper presents an observational study of the tornado outbreak that took place on the 7 September 2005 in the Llobregat delta river, affecting a densely populated and urbanised area and the Barcelona International airport (NE Spain. The site survey confirmed at least five short-lived tornadoes. Four of them were weak (F0, F1 and the other one was significant (F2 on the Fujita scale. They started mostly as waterspouts and moved later inland causing extensive damage estimated in 9 million Euros, three injured people but fortunately no fatalities. Large scale forcing was provided by upper level diffluence and low level warm air advection. Satellite and weather radar images revealed the development of the cells that spawned the waterspouts along a mesoscale convergence line in a highly sheared and relatively low buoyant environment. Further analysis indicated characteristics that could be attributed indistinctively to non-supercell or to mini-supercell thunderstorms.

Response of centrifugal blowers to simulated tornado transients, July-September 1981

International Nuclear Information System (INIS)

Idar, E.S.; Gregory, W.S.; Martin, R.A.; Littleton, P.E.

1982-03-01

During this quarter, quasi-steady and dynamic testing of the 24-in. centrifugal blower was completed using the blowdown facility located at New Mexico State University. The data were obtained using a new digital data-acquisition system. Software was developed at the Los Alamos National Laboratory to reduce the dynamic test data and create computer-generated movies showing the dynamic performance of the blower under simulated tornado transient pressure conditions relative to its quasi-steady-state performance. Currently, quadrant-four (outrunning flow) data have been reduced for the most severe and a less severe tornado pressure transient. The results indicate that both the quasi-steady and dynamic blower performance are very similar. Some hysteresis in the dynamic performance occurs because of rotational inertia effects in the blower rotor and drive system. Currently quadrant-two (backflow) data are being transferred to the LTSS computer system at Los Alamos and will be reduced shortly

Simulation of the Tornado Event of 22 March, 2013 over ...

Indian Academy of Sciences (India)

An attempt has been made to simulate this rare event using the Weather Research and Forecasting (WRF) model. The model was run in a single domain at 9 km resolution for a period of 24 hrs, starting at 0000 UTC on 22 March, 2013. The meteorological conditions that led to form this tornado have been analyzed.

Gliding arc in tornado using a reverse vortex flow

International Nuclear Information System (INIS)

Kalra, Chiranjeev S.; Cho, Young I.; Gutsol, Alexander; Fridman, Alexander; Rufael, Tecle S.

2005-01-01

The present article reports a new gliding arc (GA) system using a reverse vortex flow ('tornado') in a cylindrical reactor (gliding arc in tornado, or GAT), as used to preserve the main advantages of traditional GA systems and overcome their main drawbacks. The primary advantages of traditional GA systems retained in the present GAT are the possibility to generate transitional plasma and to avoid considerable electrode erosion. In contrast to a traditional GA, the new GAT system ensures much more uniform gas treatment and has a significantly larger gas residence time in the reactor. The present article also describes the design of the new reactor and its stable operation regime when the variation of GAT current is very small. These features are understood to be very important for most viable applications. Additionally the GAT provides near-perfect thermal insulation from the reactor wall, indicating that the present GAT does not require the reactor wall to be constructed of high-temperature materials. The new GAT system, with its unique properties such as a high level of nonequilibrium and a large residence time, looks very promising for many industrial applications including fuel conversion, carbon dioxide conversion to carbon monoxide and oxygen, surface treatment, waste treatment, flame stabilization, hydrogen sulfide treatment, etc

Geomorphological impacts of a tornado disturbance in a subtropical forest

Science.gov (United States)

Jonathan Phillips; Daniel A. Marion; Chad Yocum; Stephanie H. Mehlhope; Jeff W. Olson

2015-01-01

We studied tree uprooting associated with an EF2 tornado that touched down in portions of the Ouachita Mountains in western Arkansas in 2009. In the severe blowdown areas all trees in the mixed shortleaf pine–hardwood forest were uprooted or broken, with no relationship between tree species or size and whether uprooting or breakage occurred. There was also no...

Sounding-derived parameters associated with large hail and tornadoes in the Netherlands

NARCIS (Netherlands)

Groenemeijer, P.H.; van Delden, A.J.|info:eu-repo/dai/nl/072670703

2007-01-01

A study is presented focusing on the potential value of parameters derived from radiosonde data or data from numerical atmospheric models for the forecasting of severe weather associated with convective storms. Parameters have been derived from soundings in the proximity of large hail, tornadoes

Tornado hazard communication disparities among Spanish-speaking individuals in an English-speaking community.

Science.gov (United States)

Ahlborn, Leslie; Franc, Jeffrey Michael

2012-02-01

The state of Oklahoma, known for destructive tornados, has a native Spanish-speaking (NSS) population of approximately 180,241, of which 50% report being able to speak English "very well" (US Census Bureau). With almost 50% of these native Spanish-speaking persons being limited English proficient (LEP), their reception of tornado hazard communications may be restricted. This study conducted in northeast Oklahoma (USA) evaluates the association between native language and receiving tornado hazard communications. This study was a cross-sectional survey conducted among a convenience sample of NSS and native English-speaking (NES) adults at Xavier Clinic and St. Francis Trauma Emergency Center in Tulsa, OK, USA from September 2009 through December 2009. Of the 82 surveys administered, 80 were returned, with 40 NES and 40 NSS participants. A scoring system (Severe Weather Information Reception (SWIR)) was developed to quantify reception of hazard information among the study participants (1-3 points=poor reception, 4-5=adequate reception, 6-8=excellent reception). Pearson's chi-squared test was used to calculate differences between groups with Yates' continuity correction applied where appropriate, and SWIR scores were analyzed using ANOVA. P-valuestornado siren. NSS were less likely to have Internet access (Ptornado warning reception between NSS and NES. Poor English proficiency was noted to be 75% among NSS, which is approximately 25% more than estimated by the US Census Bureau. This study demonstrates a need for emergency managers to recognize when appropriate and overcome communication disparities among limited English proficient populations.

A concentrated outbreak of tornadoes, downbursts and microbursts, and implications regarding vortex classification

Science.gov (United States)

Forbes, G. S.; Wakimoto, R. M.

1983-01-01

A remarkable case of severe weather occurred near Springfield, Illinois on 6 August 1977. Aerial and ground surveys revealed that 17 cyclonic vortices, an anticyclonic vortex, 10 downbursts and 19 microbursts occurred in a limited (20 km x 40 km) area, associated with a bow-shaped radar echo. About half of the vortices appeared to have occurred along a gust front. Some of the others appear to have occurred within the circulation of a mesocyclone accompanying the bow echo, but these vortices seem to have developed specifically in response to localized boundary-layer vorticity generation associated with horizontal and vertical wind shears on the periphery of microbursts. Some of these vortices, and other destructive vortices in the literature, do not qualify as tornadoes as defined in the Glossary of Meteorology. A more pragmatic definition of a tornado is suggested.

Observation of gravity waves during the extreme tornado outbreak of 3 April 1974

Science.gov (United States)

Hung, R. J.; Phan, T.; Smith, R. E.

1978-01-01

A continuous wave-spectrum high-frequency radiowave Doppler sounder array was used to observe upper-atmospheric disturbances during an extreme tornado outbreak. The observations indicated that gravity waves with two harmonic wave periods were detected at the F-region ionospheric height. Using a group ray path computational technique, the observed gravity waves were traced in order to locate potential sources. The signals were apparently excited 1-3 hours before tornado touchdown. Reverse ray tracing indicated that the wave source was located at the aurora zone with a Kp index of 6 at the time of wave excitation. The summation of the 24-hour Kp index for the day was 36. The results agree with existing theories (Testud, 1970; Titheridge, 1971; Kato, 1976) for the excitation of large-scale traveling ionospheric disturbances associated with geomagnetic activity in the aurora zone.

Forest structure following tornado damage and salvage logging in northern Maine, USA

Science.gov (United States)

Shawn Fraver; Kevin J. Dodds; Laura S. Kenefic; Rick Morrill; Robert S. Seymour; Eben Sypitkowski

2017-01-01

Understanding forest structural changes resulting from postdisturbance management practices such as salvage logging is critical for predicting forest recovery and developing appropriate management strategies. In 2013, a tornado and subsequent salvage operations in northern Maine, USA, created three conditions (i.e., treatments) with contrasting forest structure:...

Tornado missile risk analysis. Topical report No. 1

International Nuclear Information System (INIS)

Dunn, W.L.; Lew, S.T.; Davis, R.L.; Hsu, J.C.; McConnell, B.S.

1976-01-01

Literature reviews, preliminary models, methodology descriptions, and general progress appraisal corresponding to the first 12 weeks of the research and approximately 14% of the budget expenditures are presented. Consequently, much of the methodology discussed in the various tasks is tentative and dependent upon further investigation as noted. The objective of this project is to develop a probabilistic formalism for characterizing the effects of the tornado generated missiles on the plant safety. The state-of-the-art nnd the R/D efforts needed to accomplish the stated objective are summarized

Proposal for evaluation methodology on impact resistant performance and construction method of tornado missile protection net structure

International Nuclear Information System (INIS)

Namba, Kosuke; Shirai, Koji

2014-01-01

In nuclear power plants, the necessity of the Tornado Missile Protection Structure is becoming a technical key issue. Utilization of the net structure seems to be one of the realistic counter measures from the point of the view of the mitigation wind and seismic loads. However, the methodology for the selection of the net suitable materials, the energy absorption design method and the construction method are not sufficiently established. In this report, three materials (high-strength metal mesh, super strong polyethylene fiber net and steel grating) were selected for the candidate material and the material screening tests, the energy absorption tests by free drop test using the heavy weight and the impact tests with the small diameter missile. As a result, high-strength metal mesh was selected as a suitable material for tornado missile protection net structure. Moreover, the construction method to obtain the good energy absorption performance of the material and the practical design method to estimate the energy absorption of the high-strength metal mesh under tornado missile impact load were proposed. (author)

Twitter as a Potential Disaster Risk Reduction Tool. Part III: Evaluating Variables that Promoted Regional Twitter Use for At-risk Populations During the 2013 Hattiesburg F4 Tornado.

Science.gov (United States)

Cooper, Guy Paul; Yeager, Violet; Burkle, Frederick M; Subbarao, Italo

2015-06-29

Study goals attempt to identify the variables most commonly associated with successful tweeted messages and determine which variables have the most influence in promoting exponential dissemination of information (viral spreading of the message) and trending (becoming popular) in the given disaster affected region. Part II describes the detailed extraction and triangulation filtration methodological approach to acquiring twitter data for the 2013 Hattiesburg Tornado. The data was then divided into two 48 hour windows before and after the tornado impact with a 2 hour pre-tornado buffer to capture tweets just prior to impact. Criteria-based analysis was completed for Tweets and users. The top 100 pre-Tornado and post-Tornado retweeted users were compared to establish the variability among the top retweeted users during the 4 day span.  Pre-Tornado variables that were correlated to higher retweeted rates include total user tweets (0.324), and total times message retweeted (0.530).  Post-Tornado variables that were correlated to higher retweeted rates include total hashtags in a retweet (0.538) and hashtags #Tornado (0.378) and #Hattiesburg (0.254). Overall hashtags usage significantly increased during the storm. Pre-storm there were 5,763 tweets with a hashtag and post-storm there was 13,598 using hashtags. Twitter's unique features allow it to be considered a unique social media tool applicable for emergency managers and public health officials for rapid and accurate two way communication.  Additionally, understanding how variables can be properly manipulated plays a key role in understanding how to use this social media platform for effective, accurate, and rapid mass information communication.

Environmental risk perception from visual cues: the psychophysics of tornado risk perception

Science.gov (United States)

Dewitt, Barry; Fischhoff, Baruch; Davis, Alexander; Broomell, Stephen B.

2015-12-01

Lay judgments of environmental risks are central to both immediate decisions (e.g., taking shelter from a storm) and long-term ones (e.g., building in locations subject to storm surges). Using methods from quantitative psychology, we provide a general approach to studying lay perceptions of environmental risks. As a first application of these methods, we investigate a setting where lay decisions have not taken full advantage of advances in natural science understanding: tornado forecasts in the US and Canada. Because official forecasts are imperfect, members of the public must often evaluate the risks on their own, by checking environmental cues (such as cloud formations) before deciding whether to take protective action. We study lay perceptions of cloud formations, demonstrating an approach that could be applied to other environmental judgments. We use signal detection theory to analyse how well people can distinguish tornadic from non-tornadic clouds, and multidimensional scaling to determine how people make these judgments. We find that participants (N = 400 recruited from Amazon Mechanical Turk) have heuristics that generally serve them well, helping participants to separate tornadic from non-tornadic clouds, but which also lead them to misjudge the tornado risk of certain cloud types. The signal detection task revealed confusion regarding shelf clouds, mammatus clouds, and clouds with upper- and mid-level tornadic features, which the multidimensional scaling task suggested was the result of participants focusing on the darkness of the weather scene and the ease of discerning its features. We recommend procedures for training (e.g., for storm spotters) and communications (e.g., tornado warnings) that will reduce systematic misclassifications of tornadicity arising from observers’ reliance on otherwise useful heuristics.

Tornado type wind turbines

Science.gov (United States)

Hsu, Cheng-Ting

1984-01-01

A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

AXAOTHER XL -- A spreadsheet for determining doses for incidents caused by tornadoes or high-velocity straight winds

International Nuclear Information System (INIS)

Simpkins, A.A.

1996-09-01

AXAOTHER XL is an Excel Spreadsheet used to determine dose to the maximally exposed offsite individual during high-velocity straight winds or tornado conditions. Both individual and population doses may be considered. Potential exposure pathways are inhalation and plume shine. For high-velocity straight winds the spreadsheet has the capability to determine the downwind relative air concentration, however for the tornado conditions, the user must enter the relative air concentration. Theoretical models are discussed and hand calculations are performed to ensure proper application of methodologies. A section has also been included that contains user instructions for the spreadsheet

ENSO-based probabilistic forecasts of March-May U.S. tornado and hail activity

Science.gov (United States)

Lepore, Chiara; Tippett, Michael K.; Allen, John T.

2017-09-01

Extended logistic regression is used to predict March-May severe convective storm (SCS) activity based on the preceding December-February (DJF) El Niño-Southern Oscillation (ENSO) state. The spatially resolved probabilistic forecasts are verified against U.S. tornado counts, hail events, and two environmental indices for severe convection. The cross-validated skill is positive for roughly a quarter of the U.S. Overall, indices are predicted with more skill than are storm reports, and hail events are predicted with more skill than tornado counts. Skill is higher in the cool phase of ENSO (La Niña like) when overall SCS activity is higher. SCS forecasts based on the predicted DJF ENSO state from coupled dynamical models initialized in October of the previous year extend the lead time with only a modest reduction in skill compared to forecasts based on the observed DJF ENSO state.

Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

International Nuclear Information System (INIS)

Smith, P.R.; Gregory, W.S.

1985-04-01

Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the same (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released

Regeneration response to tornado and salvage harvesting in a bottomland forest

Science.gov (United States)

John L. Nelson; John W. Groninger; Loretta L. Battaglia; Charles M. Ruffner

2010-01-01

A direct hit from an F4 tornado on May 2003, followed by a partial salvage logging operation at Mermet Lake State Conservation Area on the Ohio River bottoms of southern IL have provided a rare opportunity to assess the responses of a bottomland hardwood forest to severe wind and soil disturbances. The study area encompasses 700 acres and is representative of many...

Predictors for the Number of Warning Information Sources During Tornadoes.

Science.gov (United States)

Cong, Zhen; Luo, Jianjun; Liang, Daan; Nejat, Ali

2017-04-01

People may receive tornado warnings from multiple information sources, but little is known about factors that affect the number of warning information sources (WISs). This study examined predictors for the number of WISs with a telephone survey on randomly sampled residents in Tuscaloosa, Alabama, and Joplin, Missouri, approximately 1 year after both cities were struck by violent tornadoes (EF4 and EF5) in 2011. The survey included 1006 finished interviews and the working sample included 903 respondents. Poisson regression and Zero-Inflated Poisson regression showed that older age and having an emergency plan predicted more WISs in both cities. Education, marital status, and gender affected the possibilities of receiving warnings and the number of WISs either in Joplin or in Tuscaloosa. The findings suggest that social disparity affects the access to warnings not only with respect to the likelihood of receiving any warnings but also with respect to the number of WISs. In addition, historical and social contexts are important for examining predictors for the number of WISs. We recommend that the number of WISs should be regarded as an important measure to evaluate access to warnings in addition to the likelihood of receiving warnings. (Disaster Med Public Health Preparedness. 2017;11:168-172).

Tornado model for a magnetised plasma

Science.gov (United States)

Onishchenko, O. G.; Fedun, V.; Smolyakov, A.; Horton, W.; Pokhotelov, O. A.; Verth, G.

2018-05-01

A new analytical model of axially-symmetric magnetic vortices with both a twisted fluid flow and a magnetic field is proposed. The exact solution for the three-dimensional structure of the fluid velocity and the magnetic field is obtained within the framework of the ideal magnetohydrodynamic equations for an incompressible fluid in a gravitational field. A quasi-stationary localised vortex arises when the radial flow that tends to concentrate vorticity in a narrow column around the axis of symmetry is balanced by the vertical vortex advection in the axial direction. The explicit expressions for the velocity and magnetic field components are obtained. The proposed analytic model may be used to parameterise the observed solar tornadoes and can provide a new indirect way for estimating magnetic twist from the observed azimuthal velocity profiles.

EDs in the Midwest and South activate disaster plans as deadly tornadoes sweep through the region.

Science.gov (United States)

2012-05-01

Hospitals in the Midwest and South activated their disaster plans in early March to deal with a phalanx of powerful tornadoes that leveled several small towns and killed at least two dozen people. Some hospitals had to activate plans for both internal and external disasters as their own facilities were threatened. One small critical-access hospital in West Liberty, KY, sustained significant damage and had to evacuate its patients to another facility. All the hospitals credit their disaster plans and practice drills with helping them to manage the crisis as efficiently as possible. Morgan County ARH Hospital in West Liberty, KY, went for several days without an operational lab or radiology department, but staff kept the ED open for absolute emergencies. Margaret Mary Community Hospital (MMCH) in Batesville, IN, received six tornado victims, but it was prepared for many more. Administrators credit advanced warning of the storms with helping them to prepare effectively, as well as to coordinate their response with other hospitals in the area. As a level 1 trauma center, the University of Louisville Hospital in Louisville, KY, received all the most seriously injured patients in the region, even while the facility itself was under a tornado warning. Staff had to route families away from the glassed-in waiting room to the basement until the tornado warning had passed. At one point during the crisis, there were 90 patients in the hospital's ED even though the department is only equipped with 29 beds. Administrators at Huntsville Hospital in Huntsville, AL, encouraged colleagues to take advantage of smaller-scale emergencies to activate parts of their disaster plans, and to focus disaster preparation drills on their hospital's top hazard vulnerabilities.

After the storm: personal experiences following an EF4 tornado.

Science.gov (United States)

May, Olivia W; Bigham, Amy B

2012-08-01

In April of 2011, an EF4 tornado ripped through the city of Tuscaloosa, AL, leaving in its wake thousands of destroyed homes and businesses. In the hours and days that followed, the health care community of this city, as well as the entire state of Alabama and the southeastern United States, came together to provide care to hundreds of victims, recovery workers, and volunteers. Copyright © 2012 Elsevier Inc. All rights reserved.

Optimism following a tornado disaster.

Science.gov (United States)

Suls, Jerry; Rose, Jason P; Windschitl, Paul D; Smith, Andrew R

2013-05-01

Effects of exposure to a severe weather disaster on perceived future vulnerability were assessed in college students, local residents contacted through random-digit dialing, and community residents of affected versus unaffected neighborhoods. Students and community residents reported being less vulnerable than their peers at 1 month, 6 months, and 1 year after the disaster. In Studies 1 and 2, absolute risk estimates were more optimistic with time, whereas comparative vulnerability was stable. Residents of affected neighborhoods (Study 3), surprisingly, reported less comparative vulnerability and lower "gut-level" numerical likelihood estimates at 6 months, but later their estimates resembled the unaffected residents. Likelihood estimates (10%-12%), however, exceeded the 1% risk calculated by storm experts, and gut-level versus statistical-level estimates were more optimistic. Although people believed they had approximately a 1-in-10 chance of injury from future tornadoes (i.e., an overestimate), they thought their risk was lower than peers.

Plasma Channel Lenses and Plasma Tornadoes for Optical Beam Focusing and Transport

Science.gov (United States)

Hubbard, R. F.; Kaganovich, D.; Johnson, L. A.; Gordon, D. F.; Penano, J. R.; Hafizi, B.; Helle, M. H.; Mamonau, A. A.

2017-10-01

Shaped plasmas offer the possibility of manipulating laser pulses at intensities far above the damage limits for conventional optics. An example is the plasma channel, which is a cylindrical plasma column with an on-axis density minimum. Long plasma channels have been widely used to guide intense laser pulses, particularly in laser wakefield accelerators. A new concept, the ``plasma tornado'', offers the possibility of creating long plasma channels with no nearby structures and at densities lower than can be achieved by capillary discharges. A short plasma channel can focus a laser pulse in much the same manner as a conventional lens or off-axis parabola. When placed in front of the focal point of an intense laser pulse, a plasma channel lens (PCL) can reduce the effective f-number of conventional focusing optics. When placed beyond the focal point, it can act as a collimator. We will present experimental and modeling results for a new plasma tornado design, review experimental methods for generating short PCLs, and discuss potential applications. Supported by the Naval Research Laboratory Base Program.

Pseudoaneurysm of the thoracic aorta sustained during exposure to a tornado diagnosed with ECG-synchronized CT aortography.

Science.gov (United States)

Chakraborty, Amit; von Herrmann, Paul F; Embertson, Ryan E; Landwehr, Kevin P; Winkler, Michael A

2016-01-01

A case of a tornado victim with a delayed presentation of injury to the aortic isthmus is discussed. Tornado forces resemble the forces of high energy explosions, and the injuries that can occur as a result of these forces can be bizarre. The patient presented with the unique computed tomography (CT) findings of isolated pseudoaneurysm of the thoracic aorta in the absence of other traumatic injury to the thorax. Equivocal results of the initial CT aortogram (CTA) were confirmed with ECG-synchronized CTA (ECG-CTA), demonstrating the superiority of ECG-CTA as compared to standard CTA. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessment of Structural Resistance of building 4862 to Earthquake and Tornado Forces [SEC 1 and 2

International Nuclear Information System (INIS)

METCALF, I.L.

1999-01-01

This report presents the results of work done for Hanford Engineering Laboratory under contract Y213-544-12662. LATA performed an assessment of building 4862 resistance to earthquake and tornado forces

Assessment of Structural Resistance of building 4862 to Earthquake and Tornado Forces [SEC 1 and 2

Energy Technology Data Exchange (ETDEWEB)

METCALF, I.L.

1999-12-06

This report presents the results of work done for Hanford Engineering Laboratory under contract Y213-544-12662. LATA performed an assessment of building 4862 resistance to earthquake and tornado forces.

Ventilation systems analysis during tornado conditions. Progress report, October 1, 1976--April 30, 1977

International Nuclear Information System (INIS)

Gregory, W.S.; Andrae, R.W.; Duerre, K.H.; Dove, R.C.

1977-10-01

A computer code, TVENT, has been developed to predict the tornado-induced pressures and flows within an arbitrary nuclear facility ventilation system. Operational experience with TVENT in analyzing an ERDA facility has resulted in code modifications. Several architectural firms have agreed to use TVENT to analyze their designs. They will provide us with comments on the code and user's manual to make them more useful. Our investigation of the feasibility of scale model analysis to provide additional comparative data and preliminary results is presented. Preliminary calculations indicate that a distorted model would be necessary. Distortion of the Reynolds number relating the model to the prototype appears to be the most practical approach. The Idaho Chemical Processing Plant (ICPP) atmospheric protection system was analyzed using TVENT, and the results are presented. They were found to be in close agreement with the real system under steady-state conditions. For a tornado at the exhaust stack, TVENT predicted a flow increase of 70 percent through the system's HEPA filters

Investigation and Characterization of Acoustic Emissions of Tornadoes Using Arrays of Infrasound Sensors

Science.gov (United States)

Frazier, W. G.; Talmadge, C. L.; Waxler, R.; Knupp, K. R.; Goudeau, B.; Hetzer, C. H.

2017-12-01

Working in co-ordination with the NOAA Vortex Southeast (Vortex SE) research program, 9 infrasound sensor arrays were deployed at fixed sites across North Alabama, South-central Tennessee, and Northwest Georgia during March and April of 2017, to investigate the emission and characterization of infrasonic acoustic energy from tornadoes and related phenomena. Each array consisted of seven broadband acoustic sensors with calibrated frequency response from 0.02 Hz to 200 Hz. The arrays were configured in a pattern such that accurate bearings to acoustic sources could be obtained over a broad range of frequencies (nominally from 1 Hz to 100 Hz). Data were collected synchronously at a rate of 1000 samples per second. On 22 April 2017 a line of strong storms passed directly through the area being monitored producing at least three verified tornadoes. Two of these were rated at EF0 and the other an EF1. Subsequent processing of the data from several of the arrays revealed acoustic emissions from the tornadic storms ranging in frequencies below 1 Hz to frequencies greater than 10 Hz. Accurate bearings to the storms have been calculated from distances greater than 60 km. Preliminary analysis has revealed that continuous emissions occurred prior to the estimated touchdown times, while the storms were on the ground, and for short periods after the tornadoes lifted; however, the strongest emissions appeared to occur while the storms were on the ground. One of the storms passed near two arrays simultaneously, and therefore accurate an accurate track of the storm as it moved has been obtained only using the infrasound measurements. Initial results from the analysis of the infrasound data will be presented. Under Vortex SE meteorological data was collected on a large suite of sensors. Correlations between the infrasound data and the meteorological data will be investigated and discussed.

Newly identified historical tornadoes in the Czech Republic from 16th to the 20th centuries

Czech Academy of Sciences Publication Activity Database

Lacinová, M.; Munzar, Jan; Franc, M.

-, č. 83 (2007), s. 488-492 ISSN 0169-8095 Institutional research plan: CEZ:AV0Z30860518 Keywords : tornado * history * Czech Republic Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.786, year: 2007

Tornadoes and Lightning and Floods, Oh My! Weather-Related Web Sites for K-12 Science Lessons.

Science.gov (United States)

Matkins, Juanita Jo; Murphy, Denise

1999-01-01

Reviews 30 weather-related Web sites, including readability level, under the subjects of air pressure, bad meteorology, clouds, droughts, floods, hurricanes, lightning, seasons, temperature, thunderstorms, tornadoes, water cycle, weather instruments, weather on other planets, and wind. (LRW)

Inter-comparison of Rainfall Estimation from Radar and Satellite During 2016 June 23 Yancheng Tornado Event over Eastern China

Science.gov (United States)

Huang, C.; Chen, S.; Liang, Z.; Hu, B.

2017-12-01

ABSTRACT: On the afternoon of June 23, 2016, Yancheng city in eastern China was hit by a severe thunderstorm that produced a devastating tornado. This tornado was ranked as an EF4 on the Enhanced Fujita scale by China Meteorological Administration, and killed at least 99 people and injured 846 others (152 seriously). This study evaluates rainfall estimates from ground radar network and four satellite algorithms with a relatively dense rain gauge network over eastern China including Jiangsu province and its adjacent regions for the Yancheng June 23 Tornado extreme convective storm in different spatiotemporal scales (from 0.04° to 0.1° and hourly to event total accumulation). The radar network is composed of about 6 S-band Doppler weather radars. Satellite precipitation products include Integrated Multi-satellitE Retrievals for GPM (IMERG), Climate Prediction Center morphing technique (CMORPH), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Cloud Classification System (PERSIANN-CCS), and Global Satellite Mapping of Precipitation (GSMap). Relative Bias (RB), Root-Mean-Squared Error (RMSE), Correlation Coefficient (CC), Probability Of Detection (POD), False Alarm Ratio (FAR), and Critical Success Index (CSI) are used to quantify the performance of these precipitation products.

The connection between solar wind charged particles and tornadoes: Case analysis

Directory of Open Access Journals (Sweden)

Radovanović Milan M.

2013-01-01

Full Text Available The temperature of charged particles coming from the Sun ranges from several hundred thousands to several millions °C, in extreme cases. Theoretical possibilities of the hydrodynamic air mass seizing by charged particles, i. e. solar wind, are discussed in this paper. On one hand, they are characterized by extremely high temperatures, on the other, by the compression of cold air at an approximate altitude of 90 km towards the top of the cloud of the cyclone, they influence the phenomenon of extremely low temperatures. By using the Mann-Whitney U test we have tried to determine the potential link between certain indicators of solar activity and resulting disturbances in the atmosphere. Analyzed data refer to global daily values for the 2004-2010 period. Our results confirm the possibility of coupling between the charged particles and the vortex air mass movements, based on which a more detailed study of the appearance of a tornado near Sombor on May 12th, 2010, was carried out. It has also been proven that there are grounds for a causality between the sudden arrival of the solar wind charged particles, i. e. protons, and the appearance of a tornado. Based on the presented approach, elements for an entirely novel prediction model are given. [Projekat Ministarstva nauke Republike Srbije, br. III47007 i br. 176008

PROBABILISTIC HAZARD ASSESSMENT FOR TORNADOES, STRAIGHT-LINE WIND, AND EXTREME PRECIPITATION AT THE SAVANNAH RIVER SITE

Energy Technology Data Exchange (ETDEWEB)

Werth, D.; (NOEMAIL), A.; Shine, G.

2013-12-04

Recent data sets for three meteorological phenomena with the potential to inflict damage on SRS facilities - tornadoes, straight winds, and heavy precipitation - are analyzed using appropriate statistical techniques to estimate occurrence probabilities for these events in the future. Summaries of the results for DOE-mandated return periods and comparisons to similar calculations performed in 1998 by Weber, et al., are given. Using tornado statistics for the states of Georgia and South Carolina, we calculated the probability per year of any location within a 2⁰ square area surrounding SRS being struck by a tornado (the ‘strike’ probability) and the probability that any point will experience winds above set thresholds. The strike probability was calculated to be 1.15E-3 (1 chance in 870) per year and wind speeds for DOE mandated return periods of 50,000 years, 125,000 years, and 1E+7 years (USDOE, 2012) were estimated to be 136 mph, 151 mph and 221 mph, respectively. In 1998 the strike probability for SRS was estimated to be 3.53 E-4 and the return period wind speeds were 148 mph every 50,000 years and 180 mph every 125,000 years. A 1E+7 year tornado wind speed was not calculated in 1998; however a 3E+6 year wind speed was 260 mph. The lower wind speeds resulting from this most recent analysis are largely due to new data since 1998, and to a lesser degree differences in the models used. By contrast, default tornado wind speeds taken from ANSI/ANS-2.3-2011 are somewhat higher: 161 mph for return periods of 50,000 years, 173 mph every 125,000 years, and 230 mph every 1E+7 years (ANS, 2011). Although the ANS model and the SRS models are very similar, the region defined in ANS 2.3 that encompasses the SRS also includes areas of the Great Plains and lower Midwest, regions with much higher occurrence frequencies of strong tornadoes. The SRS straight wind values associated with various return periods were calculated by fitting existing wind data to a Gumbel

Development of TONBOS for simulation of liftoff and flight of objects driven by a tornado

International Nuclear Information System (INIS)

Eguchi, Yuzuru; Sugimoto, Soichiro; Hattori, Yasuo; Hirakuchi, Hiromaru

2014-01-01

A computational code, named TONBOS, is developed to evaluate liftoff and flight behaviors of unconstrained objects on the ground struck by a tornado. In this code, wind field of a tornado is approximated not only by Rankine vortex model, but Fujita's DBT-77 model. Special attention is paid to derivation of appropriate radial velocity profile of the Fujita's DBT-77 model so that local continuity of fluid is satisfied exactly. Motion of objects in flight is described with a conventional three-degree model where aerodynamic drag force and gravity are taken into account, while vertical motion of objects on the ground is assumed to be governed by lift force generated by asymmetric air flow around the objects due to ground effect. Numerical results of TONBOS have turned out to be consistent with those of previous numerical studies as well as damage of car described in the Fujita-scale classification. (author)

Numerical simulation of tornado-borne missile impact on reinforced concrete targets

International Nuclear Information System (INIS)

Tu, D.K.; Larder, R.

1979-02-01

This study is a continuation of the Lawrence Livermore Laboratory (LLL) effort to evaluate the applicability of using the finite element procedure to numerically simulate the impact of tornado-borne missiles on reinforced concrete targets. The objective of this study is to assess the back-face scab threshold of a reinforced concrete target impacted by deformable and nondeformable missiles. Several simulations were run using slug and pipe-type impacting missiles. The numerical results were compared with full-scale experimental field tests

Prevention of destructive tropical and extratropical storms, hurricanes, tornadoes, dangerous thunderstorms, and catastrophic floods

Directory of Open Access Journals (Sweden)

E. Yu. Krasilnikov

2002-01-01

Full Text Available Tropical cyclones and storms, hurricanes, powerful thunderclouds, which generate tornadoes, destructive extratropical cyclones, which result in catastrophic floods, are the powerful cloud systems that contain huge amount of water. According to the hypothesis argued in this paper, an electric field coupled with powerful clouds and electric forces play a cardinal role in supporting this huge mass of water at a high altitude in the troposphere and in the instability of powerful clouds sometimes during rather a long time duration. Based on this hypothesis, a highly effective method of volume electric charge neutralization of powerful clouds is proposed. It results in the decrease in an electric field, a sudden increase in precipitation, and subsequent degradation of powerful clouds. This method, based on the natural phenomenon, ensures the prevention of the intensification of tropical and extratropical cyclones and their transition to the storm and hurricane (typhoon stages, which makes it possible to avoid catastrophic floods. It also ensures the suppression of severe thunderclouds, which, in turn, eliminates the development of dangerous thunderstorms and the possibility of the emergence and intensification of tornadoes.

Analysis of ventilation systems subjected to tornado conditions, May 1--September 30, 1977

International Nuclear Information System (INIS)

Andrae, R.W.; Duerre, K.H.; Dove, R.C.; Smith, M.H.; Gregory, W.S.

1978-12-01

A computer code called TVENT was developed to predict variations of pressure and flow induced in nuclear facility ventilation systems by a tornado. The final revisions made to TVENT that resulted from the suggestions of several users and the application of TVENT by the Los Alamos Scientific Laboratory (LASL) to real ventilation systems, such as those in the new LASL plutonium facility are described. TVENT was also used in an investigation of scale-modeling laws for ventilation systems. Application of TVENT to the LASL plutonium facility demonstrated that the code will handle large, complex systems. The results showed that tornado-induced transients would produce pressure reversals between zones and high flow through the filters in some plenums. The investigation of any serious implications of these conditions will require a separate effort that is beyond the scope of this report. Scale models based on several different assumptions were analyzed using TVENT to determine the best approach in building a scale model. One model distorted viscosity, and another distorted compressibility. Comparison of the distorted model results with results obtained using full-scale dimensions showed conclusively that compressibility should not be distorted, but that viscosity can be distorted without significant effects

Longitudinal cross-lagged relationships between mindfulness, posttraumatic stress symptoms, and posttraumatic growth in adolescents following the Yancheng tornado in China.

Science.gov (United States)

An, Yuanyuan; Yuan, Guangzhe; Zhang, Na; Xu, Wei; Liu, Zhen; Zhou, Feng

2018-08-01

Treatment of posttraumatic stress symptoms and facilitation of posttraumatic growth are two encouraging areas of research, yet little is understood about the relationships between trait mindfulness, posttraumatic stress symptoms, and posttraumatic growth. Previous work suggests the linkages among these variables, but most studies have been conducted in adult samples. The aim of this study was to examine longitudinal cross-lagged relationships between mindfulness, posttraumatic stress symptoms, and posttraumatic growth among adolescent survivors of the 2016 Jiangsu tornado in China. Data was collected at two secondary schools located in Yancheng city, where the severe catastrophic damage occurred during the tornado. The sample included 247 adolescent survivors (59.5% girls) aged 12-14 years who were directly affected by the tornado. Participants self-reported their trait mindfulness, posttraumatic stress symptoms, and posttraumatic growth at two time points: 6-month (T1) and 9-month post-tornado (T2; attrition rate 17.4%). Cross-lagged structural equation modelling analyses were conducted. Results showed that posttraumatic stress symptoms at T1 significantly predicted reduced trait mindfulness at T2 but not posttraumatic growth; trait mindfulness at T1 did not significantly predict posttraumatic stress symptoms nor posttraumatic growth at T2; and posttraumatic growth at T1 did not predict trait mindfulness nor posttraumatic stress symptoms at T2. These findings suggested that posttraumatic stress symptoms may negatively influence the development of trait mindfulness in disaster-affected adolescents in China, and that posttraumatic growth may have unique implications for this young population which was not associated with posttraumatic stress symptoms or trait mindfulness. Copyright © 2018 Elsevier B.V. All rights reserved.

MAGNETIC FIELD IN ATYPICAL PROMINENCE STRUCTURES: BUBBLE, TORNADO, AND ERUPTION

Energy Technology Data Exchange (ETDEWEB)

Levens, P. J.; Labrosse, N. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Schmieder, B. [LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, F-92195 Meudon (France); López Ariste, A. [IRAP—CNRS UMR 5277, 14, Av. E. Belin, F-31400 Toulouse (France); Dalmasse, K. [CISL/HAO, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States); Gelly, B., E-mail: p.levens.1@research.gla.ac.uk, E-mail: brigitte.schmieder@obspm.fr [CNRS UMR 3718 THEMIS, La Laguna, Tenerife (Spain)

2016-08-01

Spectropolarimetric observations of prominences have been obtained with the THEMIS telescope during four years of coordinated campaigns. Our aim is now to understand the conditions of the cool plasma and magnetism in “atypical” prominences, namely when the measured inclination of the magnetic field departs, to some extent, from the predominantly horizontal field found in “typical” prominences. What is the role of the magnetic field in these prominence types? Are plasma dynamics more important in these cases than the magnetic support? We focus our study on three types of “atypical” prominences (tornadoes, bubbles, and jet-like prominence eruptions) that have all been observed by THEMIS in the He i D{sub 3} line, from which the Stokes parameters can be derived. The magnetic field strength, inclination, and azimuth in each pixel are obtained by using the inversion method of principal component analysis on a model of single scattering in the presence of the Hanle effect. The magnetic field in tornadoes is found to be more or less horizontal, whereas for the eruptive prominence it is mostly vertical. We estimate a tendency toward higher values of magnetic field strength inside the bubbles than outside in the surrounding prominence. In all of the models in our database, only one magnetic field orientation is considered for each pixel. While sufficient for most of the main prominence body, this assumption appears to be oversimplified in atypical prominence structures. We should consider these observations as the result of superposition of multiple magnetic fields, possibly even with a turbulent field component.

False alarms and missed events: the impact and origins of perceived inaccuracy in tornado warning systems.

Science.gov (United States)

Ripberger, Joseph T; Silva, Carol L; Jenkins-Smith, Hank C; Carlson, Deven E; James, Mark; Herron, Kerry G

2015-01-01

Theory and conventional wisdom suggest that errors undermine the credibility of tornado warning systems and thus decrease the probability that individuals will comply (i.e., engage in protective action) when future warnings are issued. Unfortunately, empirical research on the influence of warning system accuracy on public responses to tornado warnings is incomplete and inconclusive. This study adds to existing research by analyzing two sets of relationships. First, we assess the relationship between perceptions of accuracy, credibility, and warning response. Using data collected via a large regional survey, we find that trust in the National Weather Service (NWS; the agency responsible for issuing tornado warnings) increases the likelihood that an individual will opt for protective action when responding to a hypothetical warning. More importantly, we find that subjective perceptions of warning system accuracy are, as theory suggests, systematically related to trust in the NWS and (by extension) stated responses to future warnings. The second half of the study matches survey data against NWS warning and event archives to investigate a critical follow-up question--Why do some people perceive that their warning system is accurate, whereas others perceive that their system is error prone? We find that subjective perceptions are--in part-a function of objective experience, knowledge, and demographic characteristics. When considered in tandem, these findings support the proposition that errors influence perceptions about the accuracy of warning systems, which in turn impact the credibility that people assign to information provided by systems and, ultimately, public decisions about how to respond when warnings are issued. © 2014 Society for Risk Analysis.

Prevalence and Predictors of PTSD and Depression among Adolescent Victims of the Spring 2011 Tornado Outbreak

Science.gov (United States)

Adams, Zachary W.; Sumner, Jennifer A.; Danielson, Carla Kmett; McCauley, Jenna L.; Resnick, Heidi S.; Grös, Kirstin; Paul, Lisa A.; Welsh, Kyleen E.; Ruggiero, Kenneth J.

2014-01-01

Background: Relatively few studies have examined prevalence and predictors of posttraumatic stress disorder (PTSD) or major depressive episode (MDE) in disaster-affected adolescents. Fewer still have administered diagnostic measures or studied samples exposed to tornadoes, a common type of disaster. Further, methodologic problems limit the…

Probabilistic assessment of tornado-borne missile speeds. Final report

International Nuclear Information System (INIS)

Simiu, E.; Cordes, M.R.

1980-09-01

A procedure was developed for estimating speeds with which postulated missiles hit any given set of targets in a nuclear power plant or similar installation. Hit speeds corresponding to probabilities of occurrence of .0000001 were calculated for a given nuclear power plant under various assumptions concerning the magnitude of the force opposing missile take-off, direction of tornado axis of translation, number and location of missiles, and size of target area. The results of the calculations are shown to depend upon the parameters: CDA/m, where CD = drag coefficient, A = projected area, m = mass of missiles, and the ratio, k, between the minimum aerodynamic force required to cause missile take-off, and the weight of the missile

Power Scaling of the Size Distribution of Economic Loss and Fatalities due to Hurricanes, Earthquakes, Tornadoes, and Floods in the USA

Science.gov (United States)

Tebbens, S. F.; Barton, C. C.; Scott, B. E.

2016-12-01

Traditionally, the size of natural disaster events such as hurricanes, earthquakes, tornadoes, and floods is measured in terms of wind speed (m/sec), energy released (ergs), or discharge (m3/sec) rather than by economic loss or fatalities. Economic loss and fatalities from natural disasters result from the intersection of the human infrastructure and population with the size of the natural event. This study investigates the size versus cumulative number distribution of individual natural disaster events for several disaster types in the United States. Economic losses are adjusted for inflation to 2014 USD. The cumulative number divided by the time over which the data ranges for each disaster type is the basis for making probabilistic forecasts in terms of the number of events greater than a given size per year and, its inverse, return time. Such forecasts are of interest to insurers/re-insurers, meteorologists, seismologists, government planners, and response agencies. Plots of size versus cumulative number distributions per year for economic loss and fatalities are well fit by power scaling functions of the form p(x) = Cx-β; where, p(x) is the cumulative number of events with size equal to and greater than size x, C is a constant, the activity level, x is the event size, and β is the scaling exponent. Economic loss and fatalities due to hurricanes, earthquakes, tornadoes, and floods are well fit by power functions over one to five orders of magnitude in size. Economic losses for hurricanes and tornadoes have greater scaling exponents, β = 1.1 and 0.9 respectively, whereas earthquakes and floods have smaller scaling exponents, β = 0.4 and 0.6 respectively. Fatalities for tornadoes and floods have greater scaling exponents, β = 1.5 and 1.7 respectively, whereas hurricanes and earthquakes have smaller scaling exponents, β = 0.4 and 0.7 respectively. The scaling exponents can be used to make probabilistic forecasts for time windows ranging from 1 to 1000 years

Estudio descriptivo de los vórtices atmosféricos causantes de tornados en Venezuela

Directory of Open Access Journals (Sweden)

Nelson Falcón

2012-10-01

Full Text Available Los tornados y trombas marinas son fenómenos comunes en áreas tropicales y subtropicales. La ocurrencia de estos torbellinos en la atmósfera es debida a inestabilidades y fluctuaciones locales. Desde el punto vista de la Física Atmosférica son de interés los mecanismos físicos que intervienen en la atmósfera a microescala. Se discute la fundamentación microfísica de estos eventos atmosféricos en el país y se establece una síntesis fenomenológica y el modelo estándar de las trombas marinas observadas en el Lago de Valencia, Lago de Maracaibo y en otras regiones de Venezuela. Mediante la aplicación de la técnica de fotometría se realiza un análisis exploratorio de las imágenes para extraer los órdenes de magnitud de las características físicas de los vórtices causantes de las trombas marinas y tornados tropicales.

Response of air cleaning system dampers and blowers to simulated tornado transients

International Nuclear Information System (INIS)

Gregory, W.; Idar, E.; Smith, P.; Hensel, E.; Smith, E.

1985-01-01

The effects of tornado-like pressure transients upon dampers and blowers in nuclear air cleaning systems were studied. For the dampers pressure drop as a function of flow rate was obtained and an empirical relationship developed. Transient response was examined for several types of dampers, as was structural integrity. Both centrifugal and axi-vane blowers were tested and transient characteristic curves were generated in outrunning and backflow situations. The transient characteristic curves do not necessarily match the quasi-steady characteristic curves

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

Energy Technology Data Exchange (ETDEWEB)

Aponte, C.I.

2000-02-17

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

International Nuclear Information System (INIS)

Aponte, C.I.

2000-01-01

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events

Assessment of Biomass Burning Smoke Influence on Environmental Conditions for Multi-Year Tornado Outbreaks by Combining Aerosol-Aware Microphysics and Fire Emission Constraints

Science.gov (United States)

Saide, Pablo E.; Thompson, Gregory; Eidhammer, Trude; Da Silva, Arlindo M.; Pierce, R. Bradley; Carmichael, Gregory R.

2016-01-01

We use the WRF system to study the impacts of biomass burning smoke from Central America on several tornado outbreaks occurring in the US during spring. The model is configured with an aerosol-aware microphysics parameterization capable of resolving aerosol-cloud-radiation interactions in a cost-efficient way for numerical weather prediction (NWP) applications. Primary aerosol emissions are included and smoke emissions are constrained using an inverse modeling technique and satellite-based AOD observations. Simulations turning on and off fire emissions reveal smoke presence in all tornado outbreaks being studied and show an increase in aerosol number concentrations due to smoke. However, the likelihood of occurrence and intensification of tornadoes is higher due to smoke only in cases where cloud droplet number concentration in low level clouds increases considerably in a way that modifies the environmental conditions where the tornadoes are formed (shallower cloud bases and higher low-level wind shear). Smoke absorption and vertical extent also play a role, with smoke absorption at cloud-level tending to burn-off clouds and smoke absorption above clouds resulting in an increased capping inversion. Comparing these and WRF-Chem simulations configured with a more complex representation of aerosol size and composition and different optical properties, microphysics and activation schemes, we find similarities in terms of the simulated aerosol optical depths and aerosol impacts on near-storm environments. This provides reliability on the aerosol-aware microphysics scheme as a less computationally expensive alternative to WRFChem for its use in applications such as NWP and cloud-resolving simulations.

Perceptions and Experiences of K-12 Educational Leaders in Response to the 27 April 2011 Tornadoes

Science.gov (United States)

Bishop, William E.; Fifolt, Matthew; Peters, Gary B.; Gurley, D. Keith; Collins, Loucrecia

2015-01-01

The purpose of this phenomenological study was to capture first-hand accounts of K-12 educational leaders whose school districts were directly affected by the deadly 27 April 2011 tornadoes in rural Alabama, USA. This study was framed by the literature base of leadership; specifically crisis leadership and resilience theory. Findings are organised…

Analysis of Dynamic Geometric Configuration of the Aortic Channel from the Perspective of Tornado-Like Flow Organization of Blood Flow.

Science.gov (United States)

Zhorzholiani, Sh T; Mironov, A A; Talygin, E A; Tsyganokov, Yu M; Agafonov, A M; Kiknadze, G I; Gorodkov, A Yu; Bokeriya, L A

2018-03-01

Analysis of the data of morphometry of aortic casts, aortography at different pressures, and multispiral computer tomography of the aorta with contrast and normal pulse pressure showed that geometric configuration of the flow channel of the aorta during the whole cardiac cycle corresponded to the conditions of self-organization of tornado-like quasipotential flow described by exact solutions of the Navier-Stokes equation and continuity of viscous fluid typical for this type of fluid flows. Increasing pressure in the aorta leads to a decrease in the degree of approximation of the channel geometry to the ratio of exact solution and increases the risk of distortions in the structure of the flow. A mechanism of evolution of tornado-like flow in the aorta was proposed.

Seismic, high wind, tornado, and probabilistic risk assessment of the high flux isotope reactor

International Nuclear Information System (INIS)

Harris, S.P.; Hashimoto, P.S.; Dizon, J.O.; Hashimoto, P.S.

1989-01-01

Natural phenomena analyses were performed on the High Flux Isotope Reactor (HFIR). Deterministic and probabilistic evaluations were made to determine the risks resulting from earthquakes, high winds, and tornadoes. Analytic methods in conjunction with field evaluations and an earthquake experience data base evaluation methods were used to provide more realistic results in a shorter amount of time. Plant modifications completed in preparation for HFIR restart and potential future enhancements are discussed

Whole genome sequence typing to investigate the Apophysomyces outbreak following a tornado in Joplin, Missouri, 2011.

Science.gov (United States)

Etienne, Kizee A; Gillece, John; Hilsabeck, Remy; Schupp, Jim M; Colman, Rebecca; Lockhart, Shawn R; Gade, Lalitha; Thompson, Elizabeth H; Sutton, Deanna A; Neblett-Fanfair, Robyn; Park, Benjamin J; Turabelidze, George; Keim, Paul; Brandt, Mary E; Deak, Eszter; Engelthaler, David M

2012-01-01

Case reports of Apophysomyces spp. in immunocompetent hosts have been a result of traumatic deep implantation of Apophysomyces spp. spore-contaminated soil or debris. On May 22, 2011 a tornado occurred in Joplin, MO, leaving 13 tornado victims with Apophysomyces trapeziformis infections as a result of lacerations from airborne material. We used whole genome sequence typing (WGST) for high-resolution phylogenetic SNP analysis of 17 outbreak Apophysomyces isolates and five additional temporally and spatially diverse Apophysomyces control isolates (three A. trapeziformis and two A. variabilis isolates). Whole genome SNP phylogenetic analysis revealed three clusters of genotypically related or identical A. trapeziformis isolates and multiple distinct isolates among the Joplin group; this indicated multiple genotypes from a single or multiple sources. Though no linkage between genotype and location of exposure was observed, WGST analysis determined that the Joplin isolates were more closely related to each other than to the control isolates, suggesting local population structure. Additionally, species delineation based on WGST demonstrated the need to reassess currently accepted taxonomic classifications of phylogenetic species within the genus Apophysomyces.

User perception and interpretation of tornado probabilistic hazard information: Comparison of four graphical designs.

Science.gov (United States)

Miran, Seyed M; Ling, Chen; James, Joseph J; Gerard, Alan; Rothfusz, Lans

2017-11-01

Effective design for presenting severe weather information is important to reduce devastating consequences of severe weather. The Probabilistic Hazard Information (PHI) system for severe weather is being developed by NOAA National Severe Storms Laboratory (NSSL) to communicate probabilistic hazardous weather information. This study investigates the effects of four PHI graphical designs for tornado threat, namely, "four-color"," red-scale", "grayscale" and "contour", on users' perception, interpretation, and reaction to threat information. PHI is presented on either a map background or a radar background. Analysis showed that the accuracy was significantly higher and response time faster when PHI was displayed on map background as compared to radar background due to better contrast. When displayed on a radar background, "grayscale" design resulted in a higher accuracy of responses. Possibly due to familiarity, participants reported four-color design as their favorite design, which also resulted in the fastest recognition of probability levels on both backgrounds. Our study shows the importance of using intuitive color-coding and sufficient contrast in conveying probabilistic threat information via graphical design. We also found that users follows a rational perceiving-judging-feeling-and acting approach in processing probabilistic hazard information for tornado. Copyright © 2017 Elsevier Ltd. All rights reserved.

Studies of the relationship between environmental forcing and the structure and dynamics of tornado-like vortices; TOPICAL

International Nuclear Information System (INIS)

Nolan, David S.; Almgren, Ann S.; Bell, John B.

2000-01-01

Axisymmetric numerical simulations continue to provide insight into how the structure, dynamics, and maximum wind speeds of tornadoes, and other convectively-maintained vortices, are influenced by the surrounding environment. This work is continued with a new numerical model of axisymmetric incompressible flow that incorporates adaptive mesh refinement. The model dynamically increases or decreases the resolution in regions of interest as determined by a specified refinement criterion. Here, the criterion used is based on the cell Reynolds number dx dv / nu, so that the flow is guaranteed to be laminar on the scale of the local grid spacing. The model is used to investigate how the altitude and shape of the convective forcing, the size of the domain, and the effective Reynolds number (based on the choice of the eddy viscosity nu) influence the structure and dynamics of the vortex. Over a wide variety of domain and forcing geometries,the vortex Reynolds number Gamma / nu (the ratio of the far-field circulation to the eddy viscosity) is shown to be the most important parameter for determining vortex structure and behavior. Furthermore,it is found that the vertical scale of the convective forcing only affects the vortex inasmuch as this vertical scale contributes to the total strength of the convective forcing. The horizontal scale of the convective forcing, however, is found to be the fundamental length scale in the problem, in that it can determine both the circulation of the fluid that is drawn into the vortex core, and also influences the depth of the swirling boundary layer. Higher mean wind speeds are sustained as the eddy viscosity is decreased; however, it is observed that the highest wind speeds are found in the high-swirl, two-celled vortex regime rather than in the low-swirl, one-celled regime, which is in contrast with some previous results. The conclusions drawn from these results are applied to dimensional simulations with scales similar to the

Mucormycosis: a rare fungal infection in tornado victims.

Science.gov (United States)

Austin, Cindy L; Finley, Phillip J; Mikkelson, Debbie R; Tibbs, Brian

2014-01-01

This article reviews four immunocompetent patients who developed a rare fungal infection, mucormycosis, secondary to multiple traumatic injuries sustained during an EF-5 tornado in Joplin, MO. Commonly found in soil and decaying organic matter, mucorales are fungi associated with soft tissue and cutaneous infections. Onset of this fungal infection can occur without clinical signs, presenting several days to several weeks after injury, delaying diagnosis. A multidisciplinary treatment approach including aggressive antifungal therapy and aggressive surgical debridement is critical. This diagnosis should be considered in all patients presenting with injuries sustained from high-velocity embedment of debris such as natural disasters or explosions. We present four cases of mucormycosis, species Apophysomyces trapeziformis. Data reported includes predisposing factors, number of days between injury and diagnosis of mucormycosis, surgical treatment, antifungal therapy, outcomes, and potential risk factors that may have contributed to the development of mucormycosis.

Seismic, high wind, tornado, and probabilistic risk assessments of the High Flux Isotope Reactor

International Nuclear Information System (INIS)

Harris, S.P.; Stover, R.L.; Hashimoto, P.S.; Dizon, J.O.

1989-01-01

Natural phenomena analyses were performed on the High Flux Isotope Reactor (HFIR) Deterministic and probabilistic evaluations were made to determine the risks resulting from earthquakes, high winds, and tornadoes. Analytic methods in conjunction with field evaluations and an earthquake experience data base evaluation methods were used to provide more realistic results in a shorter amount of time. Plant modifications completed in preparation for HFIR restart and potential future enhancements are discussed. 5 figs

Prototipo de simulador de tornado para el combate Aéreo No. 3 (CACOM 3 de la Fuerza Aérea Colombiana (FAC

Directory of Open Access Journals (Sweden)

Jorge Mario Cárdenas Cabrera

2012-09-01

El comando CACOM 3 de la Fuerza Aérea Colombiana (FAC ha tomado la iniciativa en este aspecto y se ha dado a la tarea de estudiar este fenómeno, trabajando en el diseño de un simulador de tornados a escala, con base en el ya existente, desarrollado por el phD. Harald Eddens, introdujo modificaciones que permitan, además de generar el fenómeno, medir y controlar a través de dispositivos electrónicos algunas variables ambientales. Estos dispositivos permitirán iniciar estudios desde el comando y servir de apoyo para labores de educación de la población vulnerable en cuanto a entender cómo se forma un tornado.

Uncertainty and control in the context of a category-five tornado.

Science.gov (United States)

Afifi, Walid A; Afifi, Tamara D; Merrill, Annie

2014-10-01

The purpose of this qualitative descriptive study was to illuminate the experience and management of uncertainty during a natural disaster. Interviews were conducted with 26 survivors of a category-five tornado that entirely demolished the small, rural town of Greensburg, Kansas. Three primary themes were found in the survivors' accounts. First, the survivors experienced rapidly shifting levels and kinds of uncertainty as they proceeded through the stages of the disaster. Second, the fluidity of much-needed information added to uncertainty. Third, the feeling of lack of control over outcomes of the disaster and its aftermath was pervasive and was often managed through reliance on communal coping. Recommendations for disaster-related intervention programs are suggested. © 2014 Wiley Periodicals, Inc.

The 2011 Tuscaloosa tornado: integration of pediatric disaster services into regional systems of care.

Science.gov (United States)

Kanter, Robert K

2012-09-01

To empirically describe the integration of pediatric disaster services into regional systems of care after the April 27, 2011, tornado in Tuscaloosa, Alabama, a community with no pediatric emergency department or pediatric intensive care unit and few pediatric subspecialists. Data were obtained in interviews with key informants including professional staff and managers from public health and emergency management agencies, prehospital emergency medical services, fire departments, hospital nurses, physicians, and the trauma program coordinator. A single hospital in Tuscaloosa served 800 patients on the night of the tornado. More than 100 of these patients were children, including more than 20 with critical injuries. Many children were unaccompanied and unidentified on arrival. Resuscitation and stabilization were performed by nonpediatric prehospital and emergency department staff. More than 20 children were secondarily transported to the nearest children's hospital an hour's drive away under the care of nonpediatric local emergency medical services providers. No preventable adverse events were identified in the resuscitation and secondary transport phases of care. Stockpiled supplies and equipment were adequate to serve the needs of the disaster victims, including the children. Essential aspects of preparation include pediatric-specific clinical skills, supplies and equipment, operational disaster plans, and interagency practice embedded in everyday work. Opportunities for improvement identified include more timely response to warnings, improved practices for identifying unaccompanied children, and enhanced child safety in shelters. Successful responses depended on integration of pediatric services into regional systems of care. Copyright © 2012 Mosby, Inc. All rights reserved.

Preparing for radiological assessments in the event of a tornado strike at Argonne National Lab.-East

International Nuclear Information System (INIS)

Goodkind, M.E.; Klimczak, C.A.; Munyon, W.J.

1993-01-01

Argonne National Laboratory-East (ANL) is a Department of Energy (DOE)-owned, contractor-operated national laboratory located 22 miles southwest of downtown Chicago on a wooded, 1700-acre site. The principal nuclear facilities at ANL include a large fast neutron source (Intense Pulse Neutron Source) in which high-energy protons strike a uranium target to produce neutrons for research studies; 60 Co irradiation sources; chemical and metallurgical plutonium laboratories, some of which are currently being decommissioned; several large hot cell facilities designed for work with multicurie quantities of actinide elements and irradiated reactor fuel materials; a few small research reactors currently in different phases of being decommissioned; and a variety of research laboratories handling many different sources in various chemical and physical forms. The hazards analysis for the ANL site shows that tornado strikes are a serious threat. The site has been struck twice in the past 20 yr, receiving only minor building damage and no release of radioactivity to the environment. Although radioactive materials in general are handled in areas that provide good tornado protection, ANL is prepared to address the problems that would occur should there be a loss of control of radioactive materials due to severe building damage

Sheet thickness required for protection against the impact of a missile generated by a tornado

International Nuclear Information System (INIS)

Prats, F.; Fernandez, M. C.

2010-01-01

The tornado generated missiles are classified in three categories: piece of pipe, car and a solid sphere. These missiles can impact class structures outer areas of the plant, possibly causing damage. Specifically, can pierce tanks located within reach class and losing the required integrity of these structures. Therefore, in this paper we review the issue of the required thickness to ensure that no loss of integrity of the tanks. The paper focuses on the evaluation of the required thickness of steel sheets.

TVENT: a computer program for analysis of tornado-induced transients in ventilation systems

International Nuclear Information System (INIS)

Duerre, K.H.; Andrae, R.W.; Gregory, W.S.

1978-07-01

The report describes TVENT, a portable FORTRAN computer program for predicting flows and pressures in a ventilation system subject to a tornado. The pressure and flow values calculated by TVENT can be used as a basis for structural analysis. TVENT is a one-dimensional, lumped-parameter model with incompressible flow augmented by fluid storage. The theoretical basis for the mathematical modeling and analysis is presented, and a description of the input for the computer code is provided. Modeling techniques specific to ventilation systems are described. Sample problems illustrate the use of TVENT in analyzing ventilation systems. Other sample problems illustrate modeling techniques used in reducing complex systems

2011 Joplin, Missouri Tornado Experience, Mental Health Reactions, and Service Utilization: Cross-Sectional Assessments at Approximately 6 Months and 2.5 Years Post-Event.

Science.gov (United States)

Houston, J Brian; Spialek, Matthew L; Stevens, Jordan; First, Jennifer; Mieseler, Vicky L; Pfefferbaum, Betty

2015-10-26

Introduction. On May 22, 2011 the deadliest tornado in the United States since 1947 struck Joplin, Missouri killing 161 people, injuring approximately 1,150 individuals, and causing approximately $2.8 billion in economic losses. Methods. This study examined the mental health effects of this event through a random digit dialing sample (N = 380) of Joplin adults at approximately 6 months post-disaster (Survey 1) and a purposive convenience sample (N = 438) of Joplin adults at approximately 2.5 years post-disaster (Survey 2). For both surveys we assessed tornado experience, posttraumatic stress, depression, mental health service utilization, and sociodemographics. For Survey 2 we also assessed social support and parent report of child strengths and difficulties. Results. Probable PTSD relevance was 12.63% at Survey 1 and 26.74% at Survey 2, while current depression prevalence was 20.82% at Survey 1 and 13.33% at Survey 2. Less education and more tornado experience was generally related to greater likelihood of experiencing probable PTSD and current depression for both surveys. Men and younger participants were more likely to report current depression at Survey 1. Low levels of social support (assessed only at Survey 2) were related to more probable PTSD and current depression. For both surveys, we observed low rates of mental health service utilization, and these rates were also low for participants reporting probable PTSD and current depression. At Survey 2 we assessed parent report of child (ages 4 to 17) strengths and difficulties and found that child difficulties were more frequent for younger children (ages 4 to 10) than older children (ages 11 to 17), and that parents reporting probable PTSD reported a greater frequency of children with borderline or abnormal difficulties. Discussion. Overall our results indicate that long-term (multi-year) community disaster mental health monitoring, assessment, referral, outreach, and services are needed following a major

Behavior of critical structures and equipment at 100-N plant during a postulated tornado

International Nuclear Information System (INIS)

Davis, H.S.

1978-01-01

The objective of this report is to document the results of an analytical study for determining the effects of tornadic wind pressures and missiles on critical structures and equipment at 100-N reactor. These particular structures and equipment are essential for maintaining the reactor in a safe, shutdown condition. The analyses show that structures, systems and components required for safe reactor shutdown and operations of the Emergency Core Cooling System (ECCS) would not be damaged by a 175 mph tornado, nor associated missiles, to the extent that the ECCS would not be able to function adequately

Estudio y simulación de tornados en el área geográfica de Barranquilla

Directory of Open Access Journals (Sweden)

Ernesto Díaz

2012-09-01

En esta primera fase de la investigación se busca estudiar el comportamiento de los tornados, en el área metropolitana de Barranquilla, explorando toda la literatura disponible sobre su nivel de ocurrencia en la ciudad, los grados de destrucción que se generan en el área circundante, los datos históricos que registren el comportamiento de las variables físicas que los generan y los distintos modelos computacionales ya existentes susceptibles de ser parametrizados en la geografía local.

Brief communication "Modeling tornado dynamics and the generation of infrasound, electric and magnetic fields"

Directory of Open Access Journals (Sweden)

E. D. Schmitter

2010-02-01

Full Text Available Recent observations endorse earlier measurements of time varying electric and magnetic fields generated by tornadoes and dust devils. These signals may provide a means for early warning but together with a proper modeling approach can also provide insight into geometry and dynamics of the vortices. Our model calculations show the existence of pressure resonances characterized as acoustic duct modes with well defined frequencies. These resonances not only generate infrasound but also modulate the charge density and the velocity field and in this way lead to electric and magnetic field oscillations in the 0.5–20-Hz range that can be monitored from a distance of several kilometers.

Magnetic tornadoes as energy channels into the solar corona.

Science.gov (United States)

Wedemeyer-Böhm, Sven; Scullion, Eamon; Steiner, Oskar; van der Voort, Luc Rouppe; de la Cruz Rodriguez, Jaime; Fedun, Viktor; Erdélyi, Robert

2012-06-27

Heating the outer layers of the magnetically quiet solar atmosphere to more than one million kelvin and accelerating the solar wind requires an energy flux of approximately 100 to 300 watts per square metre, but how this energy is transferred and dissipated there is a puzzle and several alternative solutions have been proposed. Braiding and twisting of magnetic field structures, which is caused by the convective flows at the solar surface, was suggested as an efficient mechanism for atmospheric heating. Convectively driven vortex flows that harbour magnetic fields are observed to be abundant in the photosphere (the visible surface of the Sun). Recently, corresponding swirling motions have been discovered in the chromosphere, the atmospheric layer sandwiched between the photosphere and the corona. Here we report the imprints of these chromospheric swirls in the transition region and low corona, and identify them as observational signatures of rapidly rotating magnetic structures. These ubiquitous structures, which resemble super-tornadoes under solar conditions, reach from the convection zone into the upper solar atmosphere and provide an alternative mechanism for channelling energy from the lower into the upper solar atmosphere.

Estudio descriptivo de los vórtices atmosféricos causantes de tornados en Venezuela

OpenAIRE

Nelson Falcón; Odalys Sira; Alejandro Medina

2012-01-01

Los tornados y trombas marinas son fenómenos comunes en áreas tropicales y subtropicales. La ocurrencia de estos torbellinos en la atmósfera es debida a inestabilidades y fluctuaciones locales. Desde el punto vista de la Física Atmosférica son de interés los mecanismos físicos que intervienen en la atmósfera a microescala. Se discute la fundamentación microfísica de estos eventos atmosféricos en el país y se establece una síntesis fenomenológica y el modelo estándar de las trombas marinas obs...

An HIT Solution for Clinical Care and Disaster Planning: How One health Center in Joplin, MO Survived a Tornado and Avoided a Health Information Disaster.

Science.gov (United States)

Shin, Peter; Jacobs, Feygele

2012-01-01

Since taking office, President Obama has made substantial investments in promoting the diffusion of health information technology (IT). The objective of the national health IT program is, generally, to enable health care providers to better manage patient care through secure use and sharing of health information. Through the use of technologies including electronic health records, providers can better maintain patient care information and facilitate communication, often improving care outcomes. The recent tornado in Joplin, MO highlights the importance of health information technology in the health center context, and illustrates the importance of secure electronic health information systems as a crucial element of disaster and business continuity planning. This article examines the experience of a community health center in the aftermath of the major tornado that swept through the American Midwest in the spring of 2011, and provides insight into the planning for disaster survival and recovery as it relates to patient records and health center data.

Perceptions of Participating K-12 Educational Leaders' Experiences and Decisions Regarding the Crisis Caused by the April 27, 2011 Tornadoes in Rural Alabama

Science.gov (United States)

Bishop, William E., Jr.

2013-01-01

April 27, 2011, will be remembered by many as a catastrophic day and event in Alabama, and specifically by K-12 educational leaders. Natural disasters like tornadoes have a significant impact on leaders, on their decision making and, obviously, on the survival of many of their victims. The possibility and threat of a major crisis caused by natural…

Radar observations of a tornado-spawning storm complex in Southeast Brazil and Meso-Eta forecasts of this extreme event

Science.gov (United States)

Held, Gerhard; Gomes, Jorge Luis; Gomes, Ana Maria

2014-05-01

During the early afternoon of 22 September 2013, severe storms, accompanied by large hail, damaging winds, heavy precipitation and intense lightning activity, devastated a region in the southeast State of São Paulo. Several extremely intense storm cells moved at up to 80 km/h east-southeastwards, ahead of a strong cold front approaching through Paraná, which created extremely unstable conditions that led to deep convection and overshooting towers up to 18 km. At least one of theses cells spawned a tornado when it reached the town of Taquarituba. The tornado traversed the town from south-southwest to north-northeast and was responsible for 63 people injured and two fatalities. Based on the damage reported, it was at least an F3 according to the Fujita scale. The objective of the present study is to characterize this severe thunderstorm event, using different types of data, and to evaluate the forecasts provided by the Meso-Eta model centered over Bauru. The pre-frontal and frontal convective cells were tracked throughout their life-time by IPMet's Doppler radars, which cover the western and central regions of the State São Paulo, as well as northern Paraná State. Radar volume scans, generated every 7,5 min, were processed with the TITAN (Thunderstorm Identification, Tracking, Analysis and Nowcasting) Software, yielding the following preliminary results: as the storm complex traversed the Paranapanema River, which forms the border between the two states, the cells intensified drastically and shortly before reaching the town of Taquarituba, that particular cell displayed extremely strong radial shear just above the cloud base (about -20 to +35 m/s), which led to the formation of a deep meso-cyclone, from which the tornado spawned and touched down at around 14:30 LT (LT=UT-3h). Cell properties calculated by TITAN showed a drastic increase of VIL (Vertically Integrated Liquid water content) from 13:52 LT (7,9 kg/m2) to a maximum of 61,8 kg/m2 at 14:15 LT. From 14

Applications of Earth Remote Sensing for Identifying Tornado and Severe Weather Damage

Science.gov (United States)

Schultz, Lori; Molthan, Andrew; Burks, Jason E.; Bell, Jordan; McGrath, Kevin; Cole, Tony

2016-01-01

NASA SPoRT (Short-term Prediction Research and Transition Center) provided MODIS (Moderate Resolution Imaging Spectrometer) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery to WFOs (Weather Forecast Offices) in Alabama to support April 27th, 2011 damage assessments across the state. SPoRT was awarded a NASA Applied Science: Disasters Feasibility award to investigate the applicability of including remote sensing imagery and derived products into the NOAA/NWS (National Oceanic and Atmospheric Administration/National Weather System) Damage Assessment Toolkit (DAT). Proposal team was awarded the 3-year proposal to implement a web mapping service and associate data feeds from the USGS (U.S. Geological Survey) to provide satellite imagery and derived products directly to the NWS thru the DAT. In the United States, NOAA/NWS is charged with performing damage assessments when storm or tornado damage is suspected after a severe weather event. This has led to the development of the Damage Assessment Toolkit (DAT), an application for smartphones, tablets and web browsers that allows for the collection, geo-location, and aggregation of various damage indicators collected during storm surveys.

Effects of optimism on recovery and mental health after a tornado outbreak.

Science.gov (United States)

Carbone, Eric G; Echols, Erin Thomas

2017-05-01

Dispositional optimism, a stable expectation that good things will happen, has been shown to improve health outcomes in a wide range of contexts, but very little research has explored the impact of optimism on post-disaster health and well-being. Data for this study come from the Centers for Disease Control and Prevention's Public health systems and mental health community recovery (PHSMHCR) Survey. Participants included 3216 individuals living in counties affected by the April 2011 tornado outbreak in Mississippi and Alabama. This study assesses the effect of dispositional optimism on post-disaster recovery and mental health. Dispositional optimism was found to have a positive effect on personal recovery and mental health after the disaster. Furthermore, it moderated the relationship between level of home damage and personal recovery as well as the relationship between home damage and post-traumatic stress disorder (PTSD), with stronger effects for those with increased levels of home damage. The utility of screening for optimism is discussed, along with the potential for interventions to increase optimism as a means of mitigating adverse mental health effects and improving the recovery of individuals affected by disasters and other traumatic events.

The Dallas-Fort Worth (DFW) Urban Radar Network: Enhancing Resilience in the Presence of Floods, Tornadoes, Hail and High Winds

Science.gov (United States)

Chandra*, Chandrasekar V.; the full DFW Team

2015-04-01

Currently, the National Weather Service (NWS) Next Generation Weather Radar (NEXRAD) provides observations updated every five-six minutes across the United States. However, at the maximum NEXRAD operating range of 230 km, the 0.5 degree radar beam (lowest tilt) height is about 5.4 km above ground level (AGL) because of the effect of Earth curvature. Consequently, much of the lower atmosphere (1-3 km AGL) cannot be observed by the NEXRAD. To overcome the fundamental coverage limitations of today's weather surveillance radars, and improve the spatial and temporal resolution issues, at urban scale, the National Science Foundation Engineering Research Center (NSF-ERC) for Collaborative Adaptive Sensing of the Atmosphere (CASA) has embarked the development of Dallas-Fort worth (DFW) urban remote sensing network to conduct high-resolution sensing in the lower atmosphere for a metropolitan environment, communicate high resolution observations and nowcasting of severe weather including flash floods, hail storms and high wind events. Being one of the largest inland metropolitan areas in the U.S., the DFW Metroplex is home to over 6.5 million people by 2012 according to the North Central Texas Council of Governments (NCTCOG). It experiences a wide range of natural weather hazards, including urban flash flood, high wind, tornado, and hail, etc. Successful monitoring of the rapid changing meteorological conditions in such a region is necessary for emergency management and decision making. Therefore, it is an ideal location to investigate the impacts of hazardous weather phenomena, to enhance resilience in an urban setting and demonstrate the CASA concept in a densely populated urban environment. The DFW radar network consists of 8 dual-polarization X-band weather radars and standard NEXRAD S-band radar, covering the greater DFW metropolitan region. This paper will present high resolution observation of tornado, urban flood, hail storm and damaging wind event all within the

From Tornadoes to Earthquakes: Forecast Verification for Binary Events Applied to the 1999 Chi-Chi, Taiwan,Earthquake

Directory of Open Access Journals (Sweden)

Chien-Chih Chen

2006-01-01

Full Text Available Forecast verification procedures for statistical events with binary outcomes typically rely on the use of contingency tables and Relative Operating Characteristic (ROC diagrams. Originally developed for the statistical evaluation of tornado forecasts on a county-by-county basis, these methods can be adapted to the evaluation of competing earthquake forecasts. Here we apply these methods retrospectively to two forecasts for the M 7.3 1999 Chi-Chi, Taiwan, earthquake. We show that a previously proposed forecast method that is based on evaluating changes in seismic intensity on a regional basis is superior to a forecast based only on the magnitude of seismic intensity in the same region. Our results confirm earlier suggestions that the earthquake preparation process for events such as the Chi-Chi earthquake involves anomalous activation or quiescence, and that signatures of these processes can be detected in seismicity data using appropriate methods.

Comorbidity of PTSD, Major Depression, and Substance Use Disorder Among Adolescent Victims of the Spring 2011 Tornadoes in Alabama and Joplin, Missouri.

Science.gov (United States)

Adams, Zachary W; Danielson, Carla Kmett; Sumner, Jennifer A; McCauley, Jenna L; Cohen, Joseph R; Ruggiero, Kenneth J

2015-01-01

The purpose of this study was twofold: (1) to estimate the prevalence of comorbid posttraumatic stress disorder (PTSD), major depressive episode (MDE), and substance use disorder (SUD); and (2) to identify risk factors for patterns of comorbidity among adolescents affected by disasters. A population-based sample of 2,000 adolescents (51% female; 71% Caucasian, 26% African American) aged 12 to 17 years (M = 14.5, SD = 1.7) and their parents was recruited from communities affected by the spring 2011 tornadoes in Alabama and Joplin, Missouri. Participants completed structured telephone interviews assessing demographic characteristics, impact of disaster, prior trauma history, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), symptoms of posttraumatic stress disorder (PTSD) and major depressive episode (MDE), and substance use disorder (SUD) symptoms. Prevalence estimates were calculated for PTSD + MDE, PTSD + SUD, MDE + SUD, and PTSD + MDE + SUD. Hierarchical logistic regression was used to identify risk factors for each comorbidity profile. Overall prevalence since the tornado was 3.7% for PTSD + MDE, 1.1% for PTSD + SUD, 1.0% for MDE + SUD, and 0.7% for PTSD + MDE + SUD. Girls were significantly more likely than boys to meet criteria for PTSD + MDE and MDE + SUD (ps < .05). Female gender, exposure to prior traumatic events, and persistent loss of services were significant risk factors for patterns of comorbidity. Parental injury was associated with elevated risk for PTSD + MDE. Adolescents should be evaluated for comorbid problems, including SUD, following disasters so that appropriate referrals to evidence-based treatments can be made. Results suggest that screening procedures to identify adolescents at risk for comorbid disorders should assess demographic characteristics (gender), impact of the disaster on the family, and adolescents' prior history of stressful events.

EDs credit drills, community engagement with helping them manage casualties from tornado crises.

Science.gov (United States)

2011-07-01

Emergency department leaders at DCH Regional Medical Center in Tuscaloosa, AL, and Cullman Regional Medical Center in Cullman, AL, credit their regular practice drills with helping them deal with unprecedented demand when deadly tornadoes swept through the South this past April. Both facilities used the hospital instant command structure (HICS) to mobilize the resources needed to care for the surge in patients, and say the approach worked well in helping them meet the needs of their communities. However, the crises also showcased opportunities for improvement. The ED at DCH Regional Medical Center saw more than 600 patients on the day of the storm, a three-fold increase in the hospital's typical volume. CRMC treated 99 patients in the seven hours immediately following the storm when it usually treats 114 patients per day. In addition to a big surge in patients, both hospitals dealt with power outages that limited access to some services such as radiology. Triage proved particularly challenging at DCH Regional Medical Center, as patients flowed into the hospital from numerous access points. The hospital plans to assign coordinators to each area of the hospital to better manage the influx in the future. When reviewing emergency operations plans, Joint Commission reviewers often find deficiencies in hazard vulnerability analyses as well as the processes used to determine the emergency credentials of licensed independent practitioners.

Miami's Tequesta Site: Could It Be a Native American Study Site For Natural Periodicities Associated With Tornados, Hurricanes, or Earthquakes?

Science.gov (United States)

Mac Dougall, Jean S.; Mc Leod, David M.; Mc Leod, Roger D.

2002-10-01

Florida invested in preserving the Tequesta Indians' "Stonehenge-like" site along the Miami River. Direct observation, and telecast reports, show that a strong association exists between this area and Native American place names, hurricanes, tornados, a waterspout, and other nearby phenomena. Electromagnetic stimulation of human nervous systems in areas like these, discernable by appropriately sensitive individuals when these types of events occur, could plausibly account for some correct "predictions" of events like earthquakes. Various sensory modalities may be activated there. It may be important to understand other historic aspects associated with cultural artifacts like Miami's Tequesta remains. If it also generates instrumentally detectable signals that correlate with visual, "auditory," or nerve ending "tinglings" like those cited by the psychiatrist Arthur Guirdham in books like his Obsessions, applied physicists could partly vindicate the investment and also provide a net return. Society and comparative religious study may benefit.

Finite element modeling of tornado missile impact on reinforced concrete wall panels

International Nuclear Information System (INIS)

Zhang, Y.; Vallabhan, C.V.G.; McDonald, J.R.

1993-01-01

This paper describes a finite element model for the impact of large tornado-generated missiles with reinforced concrete wall panels. The analysis predicts the dynamic response of a wall panel when impacted by a missile with a large contact area such as an automobile. Quadratic finite elements are used to discretize the domain of the wall panel. Fundamental assumptions are based on the Mindlin and the related Reinsser plate theories. An 'embedded' model is employed to account for the reinforcing bars. The nonlinear behavior of concrete and steel bars are analyzed by means of time-dependent constitutive relationships. A model is proposed to describe the initial and subsequent yield surfaces of concrete material, which avoids underestimation of the effect of high hydrostatic stresses on the yielding behavior of concrete. Ottosen's four-parameter failure criterion is used to define the failure surface of concrete. A crack monitoring algorithm accounts for post-cracking and post-crushing behavior of concrete. Explicit time step integration of nonlinear dynamic equations are carried out using the finite element discretization of a concrete wall panel. As a practical application of the analysis technique, the contact failure pressure for a particular panel geometry can be calculated. The contact failure pressure and the elapsed time to failure after missile contact define a rectangular or triangular impulse loading to produce failure of the panel. Since automobile crashes are known to produce triangular impulse loads, the two pulses (failure and impact) can be compared to determine if a particular impact will fail the panels. Thus, a particular concrete panel can be analyzed to determine if it will fail under a postulated missile impact

Access and completion of a Web-based treatment in a population-based sample of tornado-affected adolescents.

Science.gov (United States)

Price, Matthew; Yuen, Erica K; Davidson, Tatiana M; Hubel, Grace; Ruggiero, Kenneth J

2015-08-01

Although Web-based treatments have significant potential to assess and treat difficult-to-reach populations, such as trauma-exposed adolescents, the extent that such treatments are accessed and used is unclear. The present study evaluated the proportion of adolescents who accessed and completed a Web-based treatment for postdisaster mental health symptoms. Correlates of access and completion were examined. A sample of 2,000 adolescents living in tornado-affected communities was assessed via structured telephone interview and invited to a Web-based treatment. The modular treatment addressed symptoms of posttraumatic stress disorder, depression, and alcohol and tobacco use. Participants were randomized to experimental or control conditions after accessing the site. Overall access for the intervention was 35.8%. Module completion for those who accessed ranged from 52.8% to 85.6%. Adolescents with parents who used the Internet to obtain health-related information were more likely to access the treatment. Adolescent males were less likely to access the treatment. Future work is needed to identify strategies to further increase the reach of Web-based treatments to provide clinical services in a postdisaster context. (c) 2015 APA, all rights reserved).

Rebuilding sustainable communities for children and families after disaster: recommendations from symposium participants in response to the April 27th, 2011 tornadoes.

Science.gov (United States)

Rush, S Craig; Houser, Rick; Partridge, Ashley

2015-02-01

Tuscaloosa, Alabama experienced a significant disaster, an EF4 tornado with 190 mile an hour winds on April 27, 2011. Fifty-two people were killed and more than 5,000 homes were severely damaged. Twelve percent of the city was destroyed and 7,000 people were immediately unemployed. This was a disaster of significant proportion and impacted everyone in the community of over 80,000. In an effort to address the needs of the community after this disaster a symposium was organized with a focus on helping children and families. More than 40 professionals and community members attended the symposium which was led by an international expert on disaster. Recommendations were established and distributed to the community and governmental organizations. The process for planning and implementing the symposium also may serve as a model for addressing future disasters.

Coarse woody debris and soil respiration 6 years post-tornado in a Piedmont forest blowdown

Science.gov (United States)

Oldfield, C.; Peterson, C. J.

2017-12-01

Severe wind disturbances can rapidly change carbon pools and fluxes in forests, causing a site to switch from a carbon sink to a source in a matter of minutes. Moreover, salvage logging after a disturbance can result in disturbed and compacted soil, altered woody debris carbon pools, and seedling mortality, all of which may further alter carbon dynamics beyond that caused by the disturbance itself. We measured down dead wood and soil respiration in the summer of 2017 at Boggs Creek Recreation Area in the Piedmont of northeast Georgia, the site of a severe tornado in 2011. Down dead wood and soil respiration were compared in control (intact forest), salvaged, and unsalvaged areas. Megagrams per hectare of down dead wood was significantly higher in the unsalvaged condition than the control or salvage logging condition (ANOVAs, pdead wood was not significantly different in the control when compared to the salvage logging condition (p=0.99). Soil respiration was significantly higher in the salvage logged condition than the control (pdead wood in a forest, and salvage logging may lead to greater soil respiration years after the initial disturbance, both of which will influence the time elapsed before a disturbed forest switches from carbon source to carbon sink. Further research is needed to determine the duration of these effects, along with the carbon consequences for other forest carbon pools.

The Relationship Between Posttraumatic Cognitive Change, Posttraumatic Stress Disorder, and Posttraumatic Growth Among Chinese Adolescents After the Yancheng Tornado: The Mediating Effect of Rumination

Science.gov (United States)

Zhang, Yi; Xu, Wei; Yuan, Guangzhe; An, Yuanyuan

2018-01-01

The aim of this study was to explore the different cognitive processes involved in the development of posttraumatic stress disorders (PTSDs) and posttraumatic growth (PTG). One year after the Yancheng tornado, 455 middle school students were assessed to study how posttraumatic cognitive change (PCC) influenced PTSD and PTG among traumatized Chinese adolescents through the role of rumination. The results indicated that intrusive rumination partly mediated the relationship between PCC and PTSD, and deliberate rumination partly mediated the relationship between PCC and PTSD and completely mediated the relationship between PCC and PTG. These results suggest that the cognitive processes of PTSD and PTG are different. Furthermore, the study also suggests that PTSD and PTG can coexist in individuals. This study may offer some suggestions for clinical practice after traumatic events. PMID:29686638

The Relationship Between Posttraumatic Cognitive Change, Posttraumatic Stress Disorder, and Posttraumatic Growth Among Chinese Adolescents After the Yancheng Tornado: The Mediating Effect of Rumination

Directory of Open Access Journals (Sweden)

Yi Zhang

2018-04-01

Full Text Available The aim of this study was to explore the different cognitive processes involved in the development of posttraumatic stress disorders (PTSDs and posttraumatic growth (PTG. One year after the Yancheng tornado, 455 middle school students were assessed to study how posttraumatic cognitive change (PCC influenced PTSD and PTG among traumatized Chinese adolescents through the role of rumination. The results indicated that intrusive rumination partly mediated the relationship between PCC and PTSD, and deliberate rumination partly mediated the relationship between PCC and PTSD and completely mediated the relationship between PCC and PTG. These results suggest that the cognitive processes of PTSD and PTG are different. Furthermore, the study also suggests that PTSD and PTG can coexist in individuals. This study may offer some suggestions for clinical practice after traumatic events.

The Relationship Between Posttraumatic Cognitive Change, Posttraumatic Stress Disorder, and Posttraumatic Growth Among Chinese Adolescents After the Yancheng Tornado: The Mediating Effect of Rumination.

Science.gov (United States)

Zhang, Yi; Xu, Wei; Yuan, Guangzhe; An, Yuanyuan

2018-01-01

The aim of this study was to explore the different cognitive processes involved in the development of posttraumatic stress disorders (PTSDs) and posttraumatic growth (PTG). One year after the Yancheng tornado, 455 middle school students were assessed to study how posttraumatic cognitive change (PCC) influenced PTSD and PTG among traumatized Chinese adolescents through the role of rumination. The results indicated that intrusive rumination partly mediated the relationship between PCC and PTSD, and deliberate rumination partly mediated the relationship between PCC and PTSD and completely mediated the relationship between PCC and PTG. These results suggest that the cognitive processes of PTSD and PTG are different. Furthermore, the study also suggests that PTSD and PTG can coexist in individuals. This study may offer some suggestions for clinical practice after traumatic events.

Dispositional mindfulness mediates the relationships of parental attachment to posttraumatic stress disorder and academic burnout in adolescents following the Yancheng tornado.

Science.gov (United States)

An, Yuanyuan; Yuan, Guangzhe; Liu, Zhen; Zhou, Yuyang; Xu, Wei

2018-01-01

Background : Previous studies have shown that parental attachment is associated with low severity of posttraumatic stress disorder (PTSD) and low academic burnout in individuals who have experienced traumatic events. Objective : The present study investigated the ways in which parental attachment is related to PTSD symptoms and academic burnout in Chinese traumatized adolescents by considering the role of dispositional mindfulness. Method : A total of 443 Chinese adolescents who had experienced a severe tornado one year prior to this study completed measures of parental attachment, dispositional mindfulness, PTSD and academic burnout. Results : The results showed that our model fitted the data well [ χ 2 /df  = 2.968, CFI = 0.971, TLI = 0.955, RMSEA (90% CI) = 0.067 (0.052-0.082)] and revealed that dispositional mindfulness partially mediates the relationship between parental attachment, PTSD severity and academic burnout. Conclusions : The findings suggested that dispositional mindfulness and parental attachment may be two critical resources in dealing with traumatization and academic burnout.

Prior Interpersonal Violence Exposure and Experiences During and After a Disaster as Predictors of Posttraumatic Stress Disorder and Depression Among Adolescent Victims of the Spring 2011 Tornadoes.

Science.gov (United States)

Resnick, Heidi; Zuromski, Kelly L; Galea, Sandro; Price, Matthew; Gilmore, Amanda K; Kilpatrick, Dean G; Ruggiero, Kenneth

2017-07-01

The purpose of the current report was to examine prior history of exposure to interpersonal violence (IPV), as compared with prior accident or prior disaster exposure, experiences during and after a disaster, and demographic variables as predictors of past month posttraumatic stress disorder (PTSD) and depression severity among adolescents exposed to the tornadoes in Alabama and Missouri. IPV exposure has been consistently identified as a unique category of potentially traumatic events (PTE) that significantly increases risk for development of PTSD and other difficulties relative to other event types among adolescents. A population-based sample of adolescents and caregivers ( N = 2,000) were recruited randomly from tornado-affected communities in Alabama and Joplin, Missouri. Participants completed structured telephone interviews on an average of 8.8 months posttornado. Prior history of IPV was prevalent (36.5%), as was reported history of accidents (25.9%) and prior disaster exposure (26.9%). Negative binomial regression analyses with PTSD and depression symptom counts for past month as outcome variables indicated that history of predisaster IPV was most robustly related to PTSD and depression symptoms, such that those with a history of IPV endorsed over 3 times the number of symptoms than those without IPV history. Final model statistics indicated that female gender, physical injury to caregiver, concern about others' safety, prior disaster, prior accident, and prior IPV exposure were also related to PTSD. Predictors of depression symptoms were similar with the exception that concern about others' safety was not a predictor and age was a predictor in the final model. It is important to evaluate potential additive effects of IPV history in addition to recent disaster exposure variables and to consider such history when developing interventions aimed to reduce or prevent symptoms of PTSD and depression among adolescents recently exposed to disaster.

Relying on the National Mobile Disaster Hospital as a business continuity strategy in the aftermath of a tornado: The Louisville experience.

Science.gov (United States)

Kearns, Randy D; Stringer, Lew; Craig, James; Godette-Crawford, Regina; Black, Paul S; Andra, David L; Winslow, James

2017-01-01

On 28th April, 2014, a tornado left much of Louisville, MS and the local hospital, Winston Medical Center, in ruin. In the USA, temporary hospital solutions have been used to augment the mainstream healthcare system since the American Civil War. As memories fade, however, the necessary readiness for a temporary hospital also fades, at times leaving a patchwork of resources either underfunded or abandoned. With the creation of the Hospital Preparedness Program, several temporary hospital solutions were created in various states across the USA. In the present case, Mississippi and North Carolina resources were used in Louisville in the aftermath of a direct impact that destroyed the hospital and nursing home. In the hours that followed, after lives were saved and patients safely relocated, a frank assessment confirmed the structural loss of the hospital. Local emergency responders, hospital staff, state and federal representatives all rallied with the aim of saving the community's only hospital. The steps taken in Louisville and the deliberate restoration of these essential services offer a learning opportunity for all involved in healthcare disaster preparedness, response and recovery.

Protection device for a thermonuclear device

International Nuclear Information System (INIS)

Kawashima, Shuichi.

1986-01-01

Purpose: To exactly detect the void coefficients of coolants even under high magnetic fields thereby detect the overheat of a thermonuclear device at an early stage. Constitution: The protecting device of this invention comprises a laser beam generation device, a laser beam detection device and an accident detection device. The laser generation device always generates laser beams, which are permeated through coolants and detected by the laser beam detection device, the optical amount of which is transmitted to the accident detection device. The accident detection device judges the excess or insufficiency of the detected optical amount with respect to the optical amount of the laser beams under the stationary state as a reference and issues an accident signal. Since only the optical cables that do not undergo the effect of the magnetic fields are exposed to high magnetic fields in the protection device of this invention, a high reliability can be maintained. (Kamimura, M.)

Device-Centric Monitoring for Mobile Device Management

Directory of Open Access Journals (Sweden)

Luke Chircop

2016-03-01

Full Text Available The ubiquity of computing devices has led to an increased need to ensure not only that the applications deployed on them are correct with respect to their specifications, but also that the devices are used in an appropriate manner, especially in situations where the device is provided by a party other than the actual user. Much work which has been done on runtime verification for mobile devices and operating systems is mostly application-centric, resulting in global, device-centric properties (e.g. the user may not send more than 100 messages per day across all applications being difficult or impossible to verify. In this paper we present a device-centric approach to runtime verify the device behaviour against a device policy with the different applications acting as independent components contributing to the overall behaviour of the device. We also present an implementation for Android devices, and evaluate it on a number of device-centric policies, reporting the empirical results obtained.

The behavior of reinforced concrete barriers subjected to the impact of tornado generated deformable missiles

International Nuclear Information System (INIS)

McMahon, P.M.; Meyers, B.L.; Buchert, K.P.

1977-01-01

The paper presents a general model for the evaluation of local effects damage including, penetration and backface spalling, of reinforced concrete barriers subjected to the impact of deformable tornado generated missiles. The model is based on an approximte force time history which assumes: 1) the initial penetration of the missile occurs without significant deformation of the missile if the strength of the missile is greater than that of the barrier. This portion of the time history is represented by a linear and finite rise time; 2) wrinkling or collapse of the missile occurs when the critical stress of the missile is exceeded. This portion of the time histroy is represented by a constant force-time relationship, although a decreaseing force might be more accurate; 3) while the missile is penetrating and wrinkling both elastic and plastic stress waves are developed in the missile, and compressive and shear stress waves are generated in he target. When the shear waves reach the backface of the slab, doagonal cracks initiating at the end of the penetrating missile are formed. These cracks propagate to the backface reinforcing where splitting cracks are formed. Finally, yield hinge lines form in the plane of reinforcing; 4) repenetration of the missile occurs after the wrinkling has caused a change in missile cross section. This repenetration results from moving the failure cone described in three above, and is also represented by the costant force time history. Using the assumptions, relationships for the penetration depth of the missile the wrinkling length of the missile, the critical missile stress, the time history of the impact and the spalling of the target are developed. (Auth.)

Power source device for thermonuclear device

International Nuclear Information System (INIS)

Ozaki, Akira.

1992-01-01

The present invention provides a small sized and economical power source device for a thermonuclear device. That is, the device comprises a conversion device having a rated power determined by a power required during a plasma current excitation period and a conversion device having a rated power determined by a power required during a plasma current maintaining period, connected in series to each other. Then, for the former conversion device, power is supplied from an electric power generator and, for the latter, power is supplied from a power system. With such a constitution, during the plasma electric current maintaining period for substantially continuous operation, it is possible to conduct bypassing paired operation for the former conversion device while the electric power generator is put under no load. Further, since a short period rated power may be suffice for the former conversion device and the electric power generator having the great rated power required for the plasma electric current excitation period, they can be reduced in the size and made economical. On the other hand, since the power required for the plasma current maintaining period is relatively small, the capacity of the continuous rated conversion device may be small, and the power can be received from the power system. (I.S.)

Device-Centric Monitoring for Mobile Device Management

OpenAIRE

Chircop, Luke; Colombo, Christian; Pace, Gordon J.

2016-01-01

The ubiquity of computing devices has led to an increased need to ensure not only that the applications deployed on them are correct with respect to their specifications, but also that the devices are used in an appropriate manner, especially in situations where the device is provided by a party other than the actual user. Much work which has been done on runtime verification for mobile devices and operating systems is mostly application-centric, resulting in global, device-centri...

Comparing UV/EUV line parameters and magnetic field in a quiescent prominence with tornadoes

Science.gov (United States)

Levens, P. J.; Labrosse, N.; Schmieder, B.; López Ariste, A.; Fletcher, L.

2017-10-01

Context. Understanding the relationship between plasma and the magnetic field is important for describing and explaining the observed dynamics of solar prominences. Aims: We determine if a close relationship can be found between plasma and magnetic field parameters, measured at high resolution in a well-observed prominence. Methods: A prominence observed on 15 July 2014 by the Interface Region Imaging Spectrograph (IRIS), Hinode, the Solar Dynamics Observatory (SDO), and the Télescope Héliographique pour l'Étude du Magnétisme et des Instabilités Solaires (THEMIS) is selected. We perform a robust co-alignment of data sets using a 2D cross-correlation technique. Magnetic field parameters are derived from spectropolarimetric measurements of the He I D3 line from THEMIS. Line ratios and line-of-sight velocities from the Mg II h and k lines observed by IRIS are compared with magnetic field strength, inclination, and azimuth. Electron densities are calculated using Fe xii line ratios from the Hinode Extreme-ultraviolet Imaging Spectrometer, which are compared to THEMIS and IRIS data. Results: We find Mg II k/h ratios of around 1.4 everywhere, similar to values found previously in prominences. Also, the magnetic field is strongest ( 30 G) and predominantly horizontal in the tornado-like legs of the prominence. The k3 Doppler shift is found to be between ±10 km s-1 everywhere. Electron densities at a temperature of 1.5 × 106 K are found to be around 109 cm-3. No significant correlations are found between the magnetic field parameters and any of the other plasma parameters inferred from spectroscopy, which may be explained by the large differences in the temperatures of the lines used in this study. Conclusions: This is the first time that a detailed statistical study of plasma and magnetic field parameters has been performed at high spatial resolution in a prominence. Our results provide important constraints on future models of the plasma and magnetic field in

The use of ZFP lossy floating point data compression in tornado-resolving thunderstorm simulations

Science.gov (United States)

Orf, L.

2017-12-01

In the field of atmospheric science, numerical models are used to produce forecasts of weather and climate and serve as virtual laboratories for scientists studying atmospheric phenomena. In both operational and research arenas, atmospheric simulations exploiting modern supercomputing hardware can produce a tremendous amount of data. During model execution, the transfer of floating point data from memory to the file system is often a significant bottleneck where I/O can dominate wallclock time. One way to reduce the I/O footprint is to compress the floating point data, which reduces amount of data saved to the file system. In this presentation we introduce LOFS, a file system developed specifically for use in three-dimensional numerical weather models that are run on massively parallel supercomputers. LOFS utilizes the core (in-memory buffered) HDF5 driver and includes compression options including ZFP, a lossy floating point data compression algorithm. ZFP offers several mechanisms for specifying the amount of lossy compression to be applied to floating point data, including the ability to specify the maximum absolute error allowed in each compressed 3D array. We explore different maximum error tolerances in a tornado-resolving supercell thunderstorm simulation for model variables including cloud and precipitation, temperature, wind velocity and vorticity magnitude. We find that average compression ratios exceeding 20:1 in scientifically interesting regions of the simulation domain produce visually identical results to uncompressed data in visualizations and plots. Since LOFS splits the model domain across many files, compression ratios for a given error tolerance can be compared across different locations within the model domain. We find that regions of high spatial variability (which tend to be where scientifically interesting things are occurring) show the lowest compression ratios, whereas regions of the domain with little spatial variability compress

Ontology-Based Device Descriptions and Device Repository for Building Automation Devices

Directory of Open Access Journals (Sweden)

Dibowski Henrik

2011-01-01

Full Text Available Device descriptions play an important role in the design and commissioning of modern building automation systems and help reducing the design time and costs. However, all established device descriptions are specialized for certain purposes and suffer from several weaknesses. This hinders a further design automation, which is strongly needed for the more and more complex building automation systems. To overcome these problems, this paper presents novel Ontology-based Device Descriptions (ODDs along with a layered ontology architecture, a specific ontology view approach with virtual properties, a generic access interface, a triple store-based database backend, and a generic search mask GUI with underlying query generation algorithm. It enables a formal, unified, and extensible specification of building automation devices, ensures their comparability, and facilitates a computer-enabled retrieval, selection, and interoperability evaluation, which is essential for an automated design. The scalability of the approach to several ten thousand devices is demonstrated.

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.

Science.gov (United States)

Balam Matagamon, Chan; Pawa Matagamon, Sagamo

2004-03-01

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

Multi-Device to Multi-Device (MD2MD Content-Centric Networking Based on Multi-RAT Device

Directory of Open Access Journals (Sweden)

Cheolhoon Kim

2017-11-01

Full Text Available This paper proposes a method whereby a device can transmit and receive information using a beacon, and also describes application scenarios for the proposed method. In a multi-device to multi-device (MD2MD content-centric networking (CCN environment, the main issue involves searching for and connecting to nearby devices. However, if a device can’t find another device that satisfies its requirements, the connection is delayed due to the repetition of processes. It is possible to rapidly connect to a device without repetition through the selection of the optimal device using the proposed method. Consequently, the proposed method and scenarios are advantageous in that they enable efficient content identification and delivery in a content-centric Internet of Things (IoT environment, in which multiple mobile devices coexist.

Graphene device and method of using graphene device

Science.gov (United States)

Bouchiat, Vincent; Girit, Caglar; Kessler, Brian; Zettl, Alexander K.

2015-08-11

An embodiment of a graphene device includes a layered structure, first and second electrodes, and a dopant island. The layered structure includes a conductive layer, an insulating layer, and a graphene layer. The electrodes are coupled to the graphene layer. The dopant island is coupled to an exposed surface of the graphene layer between the electrodes. An embodiment of a method of using a graphene device includes providing the graphene device. A voltage is applied to the conductive layer of the graphene device. Another embodiment of a method of using a graphene device includes providing the graphene device without the dopant island. A dopant island is placed on an exposed surface of the graphene layer between the electrodes. A voltage is applied to the conductive layer of the graphene device. A response of the dopant island to the voltage is observed.

Humanitarian Use Devices/Humanitarian Device Exemptions in cardiovascular medicine.

Science.gov (United States)

Kaplan, Aaron V; Harvey, Elisa D; Kuntz, Richard E; Shiran, Hadas; Robb, John F; Fitzgerald, Peter

2005-11-01

The Second Dartmouth Device Development Symposium held in October 2004 brought together leaders from the medical device community, including clinical investigators, senior representatives from the US Food and Drug Administration, large and small device manufacturers, and representatives from the financial community to examine difficult issues confronting device development. The role of the Humanitarian Use Device/Humanitarian Device Exemption (HUD/HDE) pathway in the development of new cardiovascular devices was discussed in this forum. The HUD/HDE pathway was created by Congress to facilitate the availability of medical devices for "orphan" indications, ie, those affecting HDEs have been granted (23 devices, 6 diagnostic tests). As the costs to gain regulatory approval for commonly used devices increase, companies often seek alternative ways to gain market access, including the HUD/HDE pathway. For a given device, there may be multiple legitimate and distinct indications, including indications that meet the HUD criteria. Companies must choose how and when to pursue each of these indications. The consensus of symposium participants was for the HUD/HDE pathway to be reserved for true orphan indications and not be viewed strategically as part of the clinical development plan to access a large market.

DeviceNet-based device-level control in SSRF

CERN Document Server

Leng Yong Bin; Lu Cheng Meng; Miao Hai Feng; Liu Song Qiang; Shen Guo Bao

2002-01-01

The control system of Shanghai Synchrotron Radiation Facility is an EPICS-based distributed system. One of the key techniques to construct the system is the device-level control. The author describes the design and implementation of the DeviceNet-based device controller. A prototype of the device controller was tested in the experiments of magnet power supply and the result showed a precision of 3 x 10 sup - sup 5

QoE-Aware Device-to-Device Multimedia Communications

Directory of Open Access Journals (Sweden)

Liang ZHOU

2015-08-01

Full Text Available Multimedia services over mobile device-to-device (D2D networks has recently received considerable attention. In this scenario, each device is equipped with a cellular communication interface, as well as a D2D interface over a shared medium. In this work, we study the performance properties of the mobile D2D communications in the framework of user satisfaction, and develop a fully distributed QoE-aware multimedia communication scheme (QAMCS. Specifically, we translate the opportunistic multimedia communications issue into a stochastic optimization problem, which opens up a new degree of performance to exploit. Moreover, QAMCS is designed for a heterogeneous and dynamic environment, in which user demand, device mobility, and transmission fashion may vary across different devices and applications. Importantly, QAMCS is able to maximize the user satisfaction and only needs each device to implement its own scheme individually in the absence of a central controller.

Virtual MIMO Beamforming and Device Pairing Enabled by Device-to-Device Communications for Multidevice Networks

Directory of Open Access Journals (Sweden)

Yeonjin Jeong

2017-01-01

Full Text Available We consider a multidevice network with asymmetric antenna configurations which supports not only communications between an access point and devices but also device-to-device (D2D communications for the Internet of things. For the network, we propose the transmit and receive beamforming with the channel state information (CSI for virtual multiple-input multiple-output (MIMO enabled by D2D receive cooperation. We analyze the sum rate achieved by a device pair in the proposed method and identify the strategies to improve the sum rate of the device pair. We next present a distributed algorithm and its equivalent algorithm for device pairing to maximize the throughput of the multidevice network. Simulation results confirm the advantages of the transmit CSI and D2D cooperation as well as the validity of the distributive algorithm.

Release strategies for making transferable semiconductor structures, devices and device components

Science.gov (United States)

Rogers, John A; Nuzzo, Ralph G; Meitl, Matthew; Ko, Heung Cho; Yoon, Jongseung; Menard, Etienne; Baca, Alfred J

2014-11-25

Provided are methods for making a device or device component by providing a multilayer structure having a plurality of functional layers and a plurality of release layers and releasing the functional layers from the multilayer structure by separating one or more of the release layers to generate a plurality of transferable structures. The transferable structures are printed onto a device substrate or device component supported by a device substrate. The methods and systems provide means for making high-quality and low-cost photovoltaic devices, transferable semiconductor structures, (opto-)electronic devices and device components.

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture

Science.gov (United States)

McCown, Steven H [Rigby, ID; Derr, Kurt W [Idaho Falls, ID; Rohde, Kenneth W [Idaho Falls, ID

2012-05-08

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture are described. According to one embodiment, a wireless device monitoring method includes accessing device configuration information of a wireless device present at a secure area, wherein the device configuration information comprises information regarding a configuration of the wireless device, accessing stored information corresponding to the wireless device, wherein the stored information comprises information regarding the configuration of the wireless device, comparing the device configuration information with the stored information, and indicating the wireless device as one of authorized and unauthorized for presence at the secure area using the comparing.

Class 1 devices case studies in medical devices design

CERN Document Server

Ogrodnik, Peter J

2014-01-01

The Case Studies in Medical Devices Design series consists of practical, applied case studies relating to medical device design in industry. These titles complement Ogrodnik's Medical Device Design and will assist engineers with applying the theory in practice. The case studies presented directly relate to Class I, Class IIa, Class IIb and Class III medical devices. Designers and companies who wish to extend their knowledge in a specific discipline related to their respective class of operation will find any or all of these titles a great addition to their library. Class 1 Devices is a companion text to Medical Devices Design: Innovation from Concept to Market. The intention of this book, and its sister books in the series, is to support the concepts presented in Medical Devices Design through case studies. In the context of this book the case studies consider Class I (EU) and 510(k) exempt (FDA) . This book covers classifications, the conceptual and embodiment phase, plus design from idea to PDS. These title...

Tornáda v České republice

OpenAIRE

Šáfrová, Martina

2014-01-01

The Bachelor work is devoted to the task of occurance the tornado over our territory. The goal of the work is on the basis of available czech and foreing literature to make acquaintance with the pesent physique knowledge of organised convection rise and tornado formation. The second goal was to show overview of tornado rise during the last ten years and introduct several tornado rise studyings. There were calculated precursors of strong convection for these rise studyings and there values wer...

PLASMA DEVICE

Science.gov (United States)

Gow, J.D.; Wilcox, J.M.

1961-12-26

A device is designed for producing and confining highenergy plasma from which neutrons are generated in copious quantities. A rotating sheath of electrons is established in a radial electric field and axial magnetic field produced within the device. The electron sheath serves as a strong ionizing medium to gas introdueed thereto and also functions as an extremely effective heating mechanism to the resulting plasma. In addition, improved confinement of the plasma is obtained by ring magnetic mirror fields produced at the ends of the device. Such ring mirror fields are defined by the magnetic field lines at the ends of the device diverging radially outward from the axis of the device and thereafter converging at spatial annular surfaces disposed concentrically thereabout. (AFC)

Practical microwave electron devices

CERN Document Server

Meurant, Gerard

2013-01-01

Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions.

Medical Devices; General Hospital and Personal Use Devices; Classification of the Ultraviolet Radiation Chamber Disinfection Device. Final order.

Science.gov (United States)

2015-11-20

The Food and Drug Administration (FDA or the Agency) is classifying the ultraviolet (UV) radiation chamber disinfection device into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the UV radiation chamber disinfection device classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Cost vs. safety: A novel design for t

Directory of Open Access Journals (Sweden)

Komali Kantamaneni

2017-08-01

Full Text Available Tornadoes are dangerous and destructive weather phenomena. The strongest category of tornadoes on the enhanced Fujita and TORRO scales is responsible for 75% of property destruction and deaths across the globe. These issues highlight the need for new design practices aimed at producing tornado proof homes in particular 3D CAD models in tornado prone zones at current climatic scenarios. Previous studies were entirely based on traditional slants and failed to offer a reliable tornado proof home, other than small rooms and trailers, while, none of the literature concentrated on multiple factors (cost, safety and high-wind proof. Therefore, a knowledge gap exists. In order to address the current research gap, this study attempts to develop an innovative 3D CAD model for tornado resistant homes by incorporating 2 PA (Two Path Analysis. Consequently, this study provides a new design using a 3D-CAD model for a tornado resistant home as in Path One and cost and safety scenarios in Path Two. However, this new design utilizes missile steel and shield technology. Preliminary results showed that, while this new design is safer and more technically sophisticated, it involves an increase of 25–30% in construction costs. However, this increased expense is low in comparison with rebuilding costs.

Wave–particle resonances and redistribution/losses of fast ions in tokamaks

International Nuclear Information System (INIS)

Nabais, F.; Borba, D.; Kiptily, V.G.; Pinches, S.D.; Sharapov, S.E.

2012-01-01

Enhanced fast ion losses, mostly in the range of energies from around 1.2 to 2.4 MeV, were measured during the activity of tornado modes in the JET tokamak. Tornado modes are TAE localized inside the q = 1 surface, which do not extend to the outer regions of the plasma. Thus, it is necessary to find an explanation on how such modes can lead to the loss of fast ions. In this paper, a mechanism that allows explaining the loss of fast ions triggered by tornado modes is proposed. This mechanism is based on the combined effect of tornado modes and global TAEs over the fast ions (global TAEs were always observed along with the tornado modes in the experiments in which enhanced losses were measured). Tornado modes would trigger the process of loss by resonantly interacting with the fast ions near the centre of the plasma and transporting the ions to a more peripheral region where tornado modes and global TAEs coexist. The TAE would then transport convectively the fast ions, most efficiently through the first bounce resonances (p = 1), all the way to the plasma edge eventually leading to its loss. This mechanism of loss is supported by calculations carried out with the CASTOR-K code. (paper)

Reaping a Harvest of Hope - Continuum Magazine | NREL

Science.gov (United States)

Reaping a Harvest of Hope On May 4, 2007, an EF-5 tornado-the highest rating of tornados-tore Reaping a Harvest of Hope Five years after a devastating tornado, Greensburg, Kansas, has new energy and a city also relied on NREL's life-cycle cost analysis and its extensive energy project development and

Photovoltaic device

Energy Technology Data Exchange (ETDEWEB)

Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R

2017-03-21

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

Photovoltaic device

Science.gov (United States)

Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

2015-06-02

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

High voltage semiconductor devices and methods of making the devices

Energy Technology Data Exchange (ETDEWEB)

Matocha, Kevin; Chatty, Kiran; Banerjee, Sujit

2018-01-23

A multi-cell MOSFET device including a MOSFET cell with an integrated Schottky diode is provided. The MOSFET includes n-type source regions formed in p-type well regions which are formed in an n-type drift layer. A p-type body contact region is formed on the periphery of the MOSFET. The source metallization of the device forms a Schottky contact with an n-type semiconductor region adjacent the p-type body contact region of the device. Vias can be formed through a dielectric material covering the source ohmic contacts and/or Schottky region of the device and the source metallization can be formed in the vias. The n-type semiconductor region forming the Schottky contact and/or the n-type source regions can be a single continuous region or a plurality of discontinuous regions alternating with discontinuous p-type body contact regions. The device can be a SiC device. Methods of making the device are also provided.

Process control device

International Nuclear Information System (INIS)

Hayashi, Toshifumi; Kobayashi, Hiroshi.

1994-01-01

A process control device comprises a memory device for memorizing a plant operation target, a plant state or a state of equipments related with each other as control data, a read-only memory device for storing programs, a plant instrumentation control device or other process control devices, an input/output device for performing input/output with an operator, and a processing device which conducts processing in accordance with the program and sends a control demand or a display demand to the input/output device. The program reads out control data relative to a predetermined operation target, compares and verify them with actual values to read out control data to be a practice premise condition which is further to be a practice premise condition if necessary, thereby automatically controlling the plant or requiring or displaying input. Practice presuming conditions for the operation target can be examined succesively in accordance with the program without constituting complicated logical figures and AND/OR graphs. (N.H.)

A database about the tornadic activity in Catalonia (NE Spain) since 1994

Science.gov (United States)

Morales, M. E.; Arús, J.; Llasat, M. C.; Castán, S.

2009-09-01

Although tornadic activity is not the most important hazard in Spain, the damages that tornadoes and downburst generate are considerable in urban areas, giving place in some occasions to casualties. In Spain, the oldest systematic works collecting data about tornadoes, refer to the Balearic Islands, although some series about tornadoes in Spain have also been collected and analysed (Gayà, 2005). These series shows a positive increase that is probably more related to a change in the perception level of the population than to climatic change. In some occasions it is difficult to separate the damages produced by the tornado itself from those produced by other associated hazards like heavy rains, hail or a wind storms. It was the case of the September 2006 event, in which flash floods and tornadoes were recorded. In the same sense in some occasions, damages produced by a downsburt are confused with those that produced by a tornado. Having in mind all these facts, having a good systematic data base about tornadoes is necessary, before to obtain some conclusions not enough justified. This kind of database is not easy to obtain, because of it requires to have detailed information about damages, meteorological observations and testimonies that has to be filtered by a good quality control. After a general presentation about tornadoes and downsbursts in Mediterranean Region, this contribution presents the database that have affected Catalonia during the period 1994-2009, starting with the tornado recorded on the Espluga de Francolí the 31 August 1994.This database has been built in basis to the AEMET information, the Consorcio de Compensación de Seguros (the insurance company of Spain for natural disasters), the newspapers and field visits to the affected places.

Tornadoes

Science.gov (United States)

... How to Guides to Protect Your Property or Business from High Winds (PDF) American Red Cross (link) Related Active Shooter Avalanche Bioterrorism Chemical Emergencies Cybersecurity Drought Earthquakes Emergency Alerts Explosions Extreme Heat Floods ...

Severe weather data near nuclear power station and reprocessing fuel facility in Japan

International Nuclear Information System (INIS)

Nagata, Tadahisa

2017-01-01

The main weather data are updated at any time. The strong wind and tornado (strong wind/tornado) data are opened until March 2016 in Japan. The main weather and the strong wind/tornado data near the nuclear power station (NPS) were investigated. The earthquake, Tunami and volcano were not mentioned on this report. The main weather data might not be severe. The maximum temperature had not been considered in the safety analysis of NPS. The weather data of some small observation posts near NPSs had not been considered. The unusual high temperature and the local severe rain near NPS by the global warming may be considered in future. The maximum intensities of the strong wind/tornado in Japan and near NPS were Fujita-scale 3 and 2, respectively. The maximum intensities of almost half NPSs were Fujita-scale 1. The intensity and the number of the strong winds/tornados differed depending on NPS. The Japanese main weather and strong wind/tornado might not be severe compared with other country. (author)

Hip supporting device

DEFF Research Database (Denmark)

2011-01-01

The present invention relates to a device for limiting movements in one or more anatomical joints, such as a device for limiting movement in the human hip joint after hip replacement surgery. This is provided by a device for limiting movement in the human hip joint, said device comprising: at least...

Cooling device in thermonuclear device

International Nuclear Information System (INIS)

Honda, Tsutomu.

1988-01-01

Purpose: To prevent loss of cooling effect over the entire torus structure directly after accidental toubles in a cooling device of a thermonuclear device. Constitution: Coolant recycling means of a cooling device comprises two systems, which are alternately connected with in-flow pipeways and exit pipeways of adjacent modules. The modules are cooled by way of the in-flow pipeways and the exist pipeways connected to the respective modules by means of the coolant recycling means corresponding to the respective modules. So long as one of the coolant recycling means is kept operative, since every one other modules of the torus structure is still kept cooled, the heat generated from the module put therebetween, for which the coolant recycling is interrupted, is removed by means of heat conduction or radiation from the module for which the cooling is kept continued. No back-up emergency cooling system is required and it can provide high economic reliability. (Kamimura, M.)

Photovoltaic device

Science.gov (United States)

Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

2015-09-01

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

78 FR 68714 - Medical Devices; Ophthalmic Devices; Classification of the Scleral Plug

Science.gov (United States)

2013-11-15

... amendments), as ``preamendments devices.'' FDA classifies these devices after the Agency takes the following.... FDA-2012-N-1238] Medical Devices; Ophthalmic Devices; Classification of the Scleral Plug AGENCY: Food... scleral plugs in order to provide a reasonable assurance of safety and effectiveness of the device. The...

21 CFR 864.9195 - Blood mixing devices and blood weighing devices.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood mixing devices and blood weighing devices. 864.9195 Section 864.9195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Products Used In Establishments That...

Sealing device

Science.gov (United States)

Garcia-Crespo, Andres Jose

2013-12-10

A sealing device for sealing a gap between a dovetail of a bucket assembly and a rotor wheel is disclosed. The sealing device includes a cover plate configured to cover the gap and a retention member protruding from the cover plate and configured to engage the dovetail. The sealing device provides a seal against the gap when the bucket assemply is subjected to a centrifugal force.

Microfluidic Device

Science.gov (United States)

Tai, Yu-Chong (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey L. (Inventor)

2017-01-01

Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

Response of ventilation dampers to large airflow pulses

International Nuclear Information System (INIS)

Gregory, W.S.; Smith, P.R.

1985-04-01

The results of an experiment program to evaluate the response of ventilation system dampers to simulated tornado transients are reported. Relevant data, such as damper response time, flow rate and pressure drop, and flow/pressure vs blade angle, were obtained, and the response of one tornado protective damper to simulated tornado transients was evaluated. Empirical relationships that will allow the data to be integrated into flow dynamics codes were developed. These flow dynamics codes can be used by safety analysts to predict the response of nuclear facility ventilation systems to tornado depressurization. 3 refs., 21 figs., 6 tabs

Radioactive waste processing device

International Nuclear Information System (INIS)

Inaguma, Masahiko; Takahara, Nobuaki; Hara, Satomi.

1996-01-01

In a processing device for filtering laundry liquid wastes and shower drains incorporated with radioactive materials, a fiber filtration device is disposed and an activated carbon filtration device is also disposed subsequent to the fiber filtration device. In addition, a centrifugal dewatering device is disposed for dewatering spent granular activated carbon in the activated carbon filtration device, and a minute filtering device is disposed for filtering the separated dewatering liquid. Filtrates filtered by the minute filtration device are recovered in a collecting tank. Namely, at first, suspended solid materials in laundry liquid wastes and shower drains are captured, and then, ingredients concerning COD are adsorbed in the activated carbon filtration device. The radioactive liquid wastes of spent granular activated carbon in the activated carbon filtration device are reduced by dewatering them by the centrifugal dewatering device, and then the granular activated carbon is subjected to an additional processing. Further, it is separated by filtration using the minute filtration device and removed as cakes. Since the filtrates are recovered to the collecting tank and filtered again, the water quality of the drains is not degraded. (N.H.)

High heat flux device of thermonuclear device

International Nuclear Information System (INIS)

Tachikawa, Nobuo.

1994-01-01

The present invention provides an equipments for high heat flux device (divertor) of a thermonuclear device, which absorbs thermal deformation during operation, has a high installation accuracy, and sufficiently withstands for thermal stresses. Namely, a heat sink member is joined to a structural base. Armour tiles are joined on the heat sink member. Cooling pipes are disposed between the heat sink member and the armour tiles. With such a constitution, the heat sink member using a highly heat conductive material having ductility, such as oxygen free copper, the cooling pipes using a material having excellent high temperature resistance and excellent elongation, such as aluminum-dispersed reinforced copper, and the armour tiles are completely joined on the structural base. Therefore, when thermal deformation tends to cause in the high heat flux device such as a divertor, cooling pipes cause no plastic deformation because of their high temperature resistance, but the heat sink member such as a oxygen free copper causes plastic deformation to absorb thermal deformation. As a result, the high heat flux device such as a divertor causes no deformation. (I.S.)

Repairing method and device for thermonuclear device

International Nuclear Information System (INIS)

Sakurai, Akiko; Masumoto, Hiroshi; Tachikawa, Nobuo.

1995-01-01

The present invention provides a method of and a device for repairing a first wall and a divertor disposed in a vacuum vessel of a thermonuclear device. Namely, an armour tile of the divertor secured, by a brazing material, in a vacuum vessel of the thermonuclear device in which high temperature plasmas of deuterium and tritium are confined to cause fusion reaction is induction-heated or heated by microwaves to melt the brazing material. Only the armour tile is thus exchanged by its attachment/detachment. This device comprises, in the vacuum vessel, an armour tile attaching/detaching manipulator and a repairing manipulator comprising a heating manipulator having induction heating coils at the top end thereof. Induction heating coils are connected to an AC power source. According to the present invention, the armour tile is exchanged without taking the divertor out of the vacuum vessel. Therefore, cutting of a divertor cooling tube for taking the divertor out of the vacuum vessel and re-welding of the divertor for attaching it to the vacuum vessel again are no more necessary. (I.S.)

Medical Device Safety

Science.gov (United States)

A medical device is any product used to diagnose, cure, or treat a condition, or to prevent disease. They ... may need one in a hospital. To use medical devices safely Know how your device works. Keep ...

Position measuring device

International Nuclear Information System (INIS)

Maeda, Kazuyuki; Takahashi, Shuichi; Maruyama, Mayumi

1998-01-01

The present invention provides a device capable of measuring accurate position and distance easily even at places where operator can not easily access, such as cell facilities for vitrifying radioactive wastes. Referring to a case of the vitrifying cell, an objective equipment settled in the cell is photographed by a photographing device. The image is stored in a position measuring device by way of an image input device. After several years, when the objective equipment is exchanged, a new objective equipment is photographed by a photographing device. The image is also stored in the position measuring device. The position measuring device compares the data of both of the images on the basis of pixel unit. Based on the image of the equipment before the exchange as a reference, extent of the displacement of the installation position of the equipment on the image after the exchange caused by installation error and manufacturing error is determined to decide the position of the equipment after exchange relative to the equipment before exchange. (I.S.)

78 FR 34669 - Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data...

Science.gov (United States)

2013-06-10

..., Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... importing wireless communication devices, portable music and data processing devices, and tablet computers... certain electronic devices, including wireless communication devices, portable music and data processing...

Novel Concepts for Device to Device Communication using Network Coding

DEFF Research Database (Denmark)

Pahlevani, Peyman; Hundebøll, Martin; Pedersen, Morten Videbæk

2014-01-01

Device-to-device communication is currently a hot research topic within 3GPP. Even though D2D communication has been part of previous ad hoc, meshed and sensor networks proposals, the main contribution by 3GPP is that the direct communication among two devices is carried out over a dynamically as...

Device configuration-management system

International Nuclear Information System (INIS)

Nowell, D.M.

1981-01-01

The Fusion Chamber System, a major component of the Magnetic Fusion Test Facility, contains several hundred devices which report status to the Supervisory Control and Diagnostic System for control and monitoring purposes. To manage the large number of diversity of devices represented, a device configuration management system was required and developed. Key components of this software tool include the MFTF Data Base; a configuration editor; and a tree structure defining the relationships between the subsystem devices. This paper will describe how the configuration system easily accomodates recognizing new devices, restructuring existing devices, and modifying device profile information

Gauging device

International Nuclear Information System (INIS)

Qurnell, F.D.; Patterson, C.B.

1979-01-01

A gauge supporting device for measuring say a square tube comprises a pair of rods or guides in tension between a pair of end members, the end members being spaced apart by a compression member or members. The tensioned guides provide planes of reference for measuring devices moved therealong on a carriage. The device is especially useful for making on site dimensional measurements of components, such as irradiated and therefore radioactive components, that cannot readily be transported to an inspection laboratory. (UK)

Implantable electronic medical devices

CERN Document Server

Fitzpatrick, Dennis

2014-01-01

Implantable Electronic Medical Devices provides a thorough review of the application of implantable devices, illustrating the techniques currently being used together with overviews of the latest commercially available medical devices. This book provides an overview of the design of medical devices and is a reference on existing medical devices. The book groups devices with similar functionality into distinct chapters, looking at the latest design ideas and techniques in each area, including retinal implants, glucose biosensors, cochlear implants, pacemakers, electrical stimulation t

Device-independent randomness amplification with a single device

International Nuclear Information System (INIS)

Plesch, Martin; Pivoluska, Matej

2014-01-01

Expansion and amplification of weak randomness with untrusted quantum devices has recently become a very fruitful topic of research. Here we contribute with a procedure for amplifying a single weak random source using tri-partite GHZ-type entangled states. If the quality of the source reaches a fixed threshold R=log 2 ⁡(10), perfect random bits can be produced. This technique can be used to extract randomness from sources that can't be extracted neither classically, nor by existing procedures developed for Santha–Vazirani sources. Our protocol works with a single fault-free device decomposable into three non-communicating parts, that is repeatedly reused throughout the amplification process. - Highlights: • We propose a protocol for device independent randomness amplification. • Our protocol repeatedly re-uses a single device decomposable into three parts. • Weak random sources with min-entropy rate greater than 1/4 log 2 ⁡(10) can be amplified. • Security against all-quantum adversaries is achieved

Smart portable rehabilitation devices

Directory of Open Access Journals (Sweden)

Leahey Matt

2005-07-01

Full Text Available Abstract Background The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s. Methods In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Results Laboratory tests of the devices

Smart portable rehabilitation devices.

Science.gov (United States)

Mavroidis, Constantinos; Nikitczuk, Jason; Weinberg, Brian; Danaher, Gil; Jensen, Katherine; Pelletier, Philip; Prugnarola, Jennifer; Stuart, Ryan; Arango, Roberto; Leahey, Matt; Pavone, Robert; Provo, Andrew; Yasevac, Dan

2005-07-12

The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s). In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Laboratory tests of the devices demonstrated that they were able to meet their design

Development of a wireless blood pressure measuring device with smart mobile device.

Science.gov (United States)

İlhan, İlhan; Yıldız, İbrahim; Kayrak, Mehmet

2016-03-01

Today, smart mobile devices (telephones and tablets) are very commonly used due to their powerful hardware and useful features. According to an eMarketer report, in 2014 there were 1.76 billion smartphone users (excluding users of tablets) in the world; it is predicted that this number will rise by 15.9% to 2.04 billion in 2015. It is thought that these devices can be used successfully in biomedical applications. A wireless blood pressure measuring device used together with a smart mobile device was developed in this study. By means of an interface developed for smart mobile devices with Android and iOS operating systems, a smart mobile device was used both as an indicator and as a control device. The cuff communicating with this device through Bluetooth was designed to measure blood pressure via the arm. A digital filter was used on the cuff instead of the traditional analog signal processing and filtering circuit. The newly developed blood pressure measuring device was tested on 18 patients and 20 healthy individuals of different ages under a physician's supervision. When the test results were compared with the measurements made using a sphygmomanometer, it was shown that an average 93.52% accuracy in sick individuals and 94.53% accuracy in healthy individuals could be achieved with the new device. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Incore instrumentation device

International Nuclear Information System (INIS)

Fujita, Kazuhiko.

1996-01-01

A position of a detector is detected by a driving device, and the detected values are sampled by a newly disposed central processing unit for sampling the detected values depending on the sampling position of the detected values. Since the sampling position of the detected values is detected by the driving device, the sampling position for the detection values does not rely on the speed of the driving motor of the driving device. The load on the central processing device for controlling the device is lowered by newly disposing the central processing unit for sampling detected values. When the values for the position of the detector counted after conversion to digital values reach the digital values corresponding to the detection value sampling position outputted from the central processing unit for controlling the device, a counted value comparison circuit causes the central processing unit for controlling the device to sample the detection values outputted from the detector. Then, the processing speed can be increased without interruption processings, which can save the central processing unit for sampling detection values. In addition, software can be simplified and loads can be lowered. (N.H.)

Inspection device in liquid

International Nuclear Information System (INIS)

Nagaoka, Etsuo.

1996-01-01

The present invention provides an inspection device in PWR reactor core in which inspection operations are made efficient by stabilizing a posture of the device in front-to-back, vertical and left-to-right directions by a simple structure. When the device conducts inspection while running in liquid, the front and the back directions of the device main body are inspected using a visual device while changing the posture by operating a front-to-back direction propulsion device and a right-to-left direction propulsion device, and a vertical direction propulsion device against to rolling, pitching and yawing of the device main body. In this case, a spherical magnet moves freely in the gravitational direction in a vibration-damping fluid in a non-magnetic spherical shell following the change of the posture of the device main body, in which the vibrations due to the movement of the spherical magnet is settled by the vibration-damping fluid thereby stabilizing the posture of the device main body. At a typical inspection posture, the settling effect is enhanced by the attraction force between the spherical magnets in the spherical shell and each of magnetic force-attracted magnetic members disposed to the outer circumference of the shell, and the posture of the device main body can be confirmed in front-to-back, right-to-left and vertical directions by each of the posture confirming magnetic sensors. (N.H.)

78 FR 16865 - Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data...

Science.gov (United States)

2013-03-19

... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-794] Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... certain electronic devices, including wireless communication devices, portable music and data processing...

Predistortion control device and method, assembly including a predistortion control device

NARCIS (Netherlands)

Kokkeler, Andre B.J.

2003-01-01

A predistortion control device (1). The device has a first predistortion control input connectable to a power amplifier output (21); a second predistortion control input (11) connectable to a signal contact of a predistortion device; and a predistortion control output (12) connectable to a control

78 FR 1247 - Certain Electronic Devices, Including Wireless Communication Devices, Tablet Computers, Media...

Science.gov (United States)

2013-01-08

... Wireless Communication Devices, Tablet Computers, Media Players, and Televisions, and Components Thereof... devices, including wireless communication devices, tablet computers, media players, and televisions, and... wireless communication devices, tablet computers, media players, and televisions, and components thereof...

Initiation devices, initiation systems including initiation devices and related methods

Energy Technology Data Exchange (ETDEWEB)

Daniels, Michael A.; Condit, Reston A.; Rasmussen, Nikki; Wallace, Ronald S.

2018-04-10

Initiation devices may include at least one substrate, an initiation element positioned on a first side of the at least one substrate, and a spark gap electrically coupled to the initiation element and positioned on a second side of the at least one substrate. Initiation devices may include a plurality of substrates where at least one substrate of the plurality of substrates is electrically connected to at least one adjacent substrate of the plurality of substrates with at least one via extending through the at least one substrate. Initiation systems may include such initiation devices. Methods of igniting energetic materials include passing a current through a spark gap formed on at least one substrate of the initiation device, passing the current through at least one via formed through the at least one substrate, and passing the current through an explosive bridge wire of the initiation device.

High energy devices versus low energy devices in orthopedics treatment modalities

Science.gov (United States)

Schultheiss, Reiner

2003-10-01

The orthopedic consensus group defined in 1997 the 42 most likely relevant parameters of orthopedic shock wave devices. The idea of this approach was to correlate the different clinical outcomes with the physical properties of the different devices with respect to their acoustical waves. Several changes in the hypothesis of the dose effect relationship have been noticed since the first orthopedic treatments. The relation started with the maximum pressure p+, followed by the total energy, the energy density; and finally the single treatment approach using high, and then the multiple treatment method using low energy. Motivated by the reimbursement situation in Germany some manufacturers began to redefine high and low energy devices independent of the treatment modality. The OssaTron as a high energy, single treatment electro hydraulic device gained FDA approval as the first orthopedic ESWT device for plantar fasciitis and, more recently, for lateral epicondylitis. Two low energy devices have now also gained FDA approval based upon a single treatment. Comparing the acoustic data, differences between the OssaTron and the other devices are obvious and will be elaborated upon. Cluster analysis of the outcomes and the acoustical data are presented and new concepts will be suggested.

77 FR 70464 - Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data...

Science.gov (United States)

2012-11-26

... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-794] Certain Electronic Devices, Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... wireless communication devices, portable music and data processing devices, and tablet computers, by reason...

Role of electric discharges in the generation of atmospheric vortices

Energy Technology Data Exchange (ETDEWEB)

Sinkevich, O. A., E-mail: oleg.sinkevich@itf.mpei.ac.ru [National Research University “MPEI,” (Russian Federation); Maslov, S. A., E-mail: sergm90@mail.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Gusein-zade, N. G., E-mail: ngus@mail.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

2017-02-15

The existing thermohydrodynamic and hydroelectromagnetic models of tornado are considered. The potentialities of the humid atmosphere as a heat engine generating air vortices are analyzed in detail. The ability of long-term atmospheric electric discharges to form a tornado funnel and create an initial twist of up to 10{sup –3}–10{sup –2} s{sup –1} in it are estimated. The possible effect of a lightning discharge on the initiation and evolution of the tornado is discussed. It is shown that the electric current flowing along the lightning channel can lead to helical instability and generation of a weak primary vortex. The channel formed in the atmosphere by a lightning discharge and the vortex motion of the parent thundercloud can enhance the primary vortex and promote its transformation into a tornado. Possible mechanisms of enhancement of the primary vortex created by a lightning discharge and the possibility of its transformation into a tornado in the postdischarge stage are discussed.

Radiation emitting devices regulations

International Nuclear Information System (INIS)

1970-01-01

The Radiation Emitting Devices Regulations are the regulations referred to in the Radiation Emitting Devices Act and relate to the operation of devices. They include standards of design and construction, standards of functioning, warning symbol specifications in addition to information relating to the seizure and detention of machines failing to comply with the regulations. The radiation emitting devices consist of the following: television receivers, extra-oral dental x-ray equipment, microwave ovens, baggage inspection x-ray devices, demonstration--type gas discharge devices, photofluorographic x-ray equipment, laser scanners, demonstration lasers, low energy electron microscopes, high intensity mercury vapour discharge lamps, sunlamps, diagnostic x-ray equipment, ultrasound therapy devices, x-ray diffraction equipment, cabinet x-ray equipment and therapeutic x-ray equipment

77 FR 60720 - Certain Electronic Devices, Including Wireless Commmunication Devices, Portable Music and Data...

Science.gov (United States)

2012-10-04

... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-794] Certain Electronic Devices, Including Wireless Commmunication Devices, Portable Music and Data Processing Devices, and Tablet Computers... communication devices, portable music and data processing devices, and tablet computers, imported by Apple Inc...

78 FR 29672 - Cardiovascular Devices; Reclassification of External Counter-Pulsating Devices for Treatment of...

Science.gov (United States)

2013-05-21

.... FDA-2013-N-0487] Cardiovascular Devices; Reclassification of External Counter- Pulsating Devices for... proposed rule (44 FR 13426, March 9, 1979), the Cardiovascular Device Classification Panel (the 1979 Panel... of Subjects in 21 CFR Part 870 Medical devices, Cardiovascular devices...

Recoil transporter devices

International Nuclear Information System (INIS)

Madhavan, N.

2005-01-01

The study of sparsely produced nuclear reaction products in the direction of intense primary beam is a challenging task, the pursuit of which has given rise to the advent or several types of selective devices. These range from a simple parallel plate electrostatic deflector to state-of-the-art electromagnetic separators. There is no single device which can satisfy all the requirements of an ideal recoil transporter, simultaneously. An overview of such devices and their building blocks is presented, which may help in the proper choice of the device as per the experimental requirements. (author)

Multiplexed charge-locking device for large arrays of quantum devices

Energy Technology Data Exchange (ETDEWEB)

Puddy, R. K., E-mail: rkp27@cam.ac.uk; Smith, L. W; Chong, C. H.; Farrer, I.; Griffiths, J. P.; Ritchie, D. A.; Smith, C. G. [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Al-Taie, H.; Kelly, M. J. [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Centre for Advanced Photonics and Electronics, Electrical Engineering Division, Department of Engineering, 9 J. J. Thomson Avenue, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Pepper, M. [Department of Electronic and Electrical Engineering, University College London, WC1E 7JE (United Kingdom)

2015-10-05

We present a method of forming and controlling large arrays of gate-defined quantum devices. The method uses an on-chip, multiplexed charge-locking system and helps to overcome the restraints imposed by the number of wires available in cryostat measurement systems. The device architecture that we describe here utilises a multiplexer-type scheme to lock charge onto gate electrodes. The design allows access to and control of gates whose total number exceeds that of the available electrical contacts and enables the formation, modulation and measurement of large arrays of quantum devices. We fabricate such devices on n-type GaAs/AlGaAs substrates and investigate the stability of the charge locked on to the gates. Proof-of-concept is shown by measurement of the Coulomb blockade peaks of a single quantum dot formed by a floating gate in the device. The floating gate is seen to drift by approximately one Coulomb oscillation per hour.

MemFlash device: floating gate transistors as memristive devices for neuromorphic computing

Science.gov (United States)

Riggert, C.; Ziegler, M.; Schroeder, D.; Krautschneider, W. H.; Kohlstedt, H.

2014-10-01

Memristive devices are promising candidates for future non-volatile memory applications and mixed-signal circuits. In the field of neuromorphic engineering these devices are especially interesting to emulate neuronal functionality. Therefore, new materials and material combinations are currently investigated, which are often not compatible with Si-technology processes. The underlying mechanisms of the device often remain unclear and are paired with low device endurance and yield. These facts define the current most challenging development tasks towards a reliable memristive device technology. In this respect, the MemFlash concept is of particular interest. A MemFlash device results from a diode configuration wiring scheme of a floating gate transistor, which enables the persistent device resistance to be varied according to the history of the charge flow through the device. In this study, we investigate the scaling conditions of the floating gate oxide thickness with respect to possible applications in the field of neuromorphic engineering. We show that MemFlash cells exhibit essential features with respect to neuromorphic applications. In particular, cells with thin floating gate oxides show a limited synaptic weight growth together with low energy dissipation. MemFlash cells present an attractive alternative for state-of-art memresitive devices. The emulation of associative learning is discussed by implementing a single MemFlash cell in an analogue circuit.

MemFlash device: floating gate transistors as memristive devices for neuromorphic computing

International Nuclear Information System (INIS)

Riggert, C; Ziegler, M; Kohlstedt, H; Schroeder, D; Krautschneider, W H

2014-01-01

Memristive devices are promising candidates for future non-volatile memory applications and mixed-signal circuits. In the field of neuromorphic engineering these devices are especially interesting to emulate neuronal functionality. Therefore, new materials and material combinations are currently investigated, which are often not compatible with Si-technology processes. The underlying mechanisms of the device often remain unclear and are paired with low device endurance and yield. These facts define the current most challenging development tasks towards a reliable memristive device technology. In this respect, the MemFlash concept is of particular interest. A MemFlash device results from a diode configuration wiring scheme of a floating gate transistor, which enables the persistent device resistance to be varied according to the history of the charge flow through the device. In this study, we investigate the scaling conditions of the floating gate oxide thickness with respect to possible applications in the field of neuromorphic engineering. We show that MemFlash cells exhibit essential features with respect to neuromorphic applications. In particular, cells with thin floating gate oxides show a limited synaptic weight growth together with low energy dissipation. MemFlash cells present an attractive alternative for state-of-art memresitive devices. The emulation of associative learning is discussed by implementing a single MemFlash cell in an analogue circuit. (paper)

FLUIDICS DEVICE FOR ASSAY

DEFF Research Database (Denmark)

2007-01-01

The present invention relates to a device for use in performing assays on standard laboratory solid supports whereon chemical entities are attached. The invention furthermore relates to the use of such a device and a kit comprising such a device. The device according to the present invention is a...

Electronic security device

Science.gov (United States)

Eschbach, Eugene A.; LeBlanc, Edward J.; Griffin, Jeffrey W.

1992-01-01

The present invention relates to a security device having a control box (12) containing an electronic system (50) and a communications loop (14) over which the system transmits a signal. The device is constructed so that the communications loop can extend from the control box across the boundary of a portal such as a door into a sealed enclosure into which access is restricted whereby the loop must be damaged or moved in order for an entry to be made into the enclosure. The device is adapted for detecting unauthorized entries into such enclosures such as rooms or containers and for recording the time at which such entries occur for later reference. Additionally, the device detects attempts to tamper or interfere with the operation of the device itself and records the time at which such events take place. In the preferred embodiment, the security device includes a microprocessor-based electronic system (50) and a detection module (72) capable of registering changes in the voltage and phase of the signal transmitted over the loop.

Electronic security device

International Nuclear Information System (INIS)

Eschbach, E.A.; LeBlanc, E.J.; Griffin, J.W.

1992-01-01

The present invention relates to a security device having a control box containing an electronic system and a communications loop over which the system transmits a signal. The device is constructed so that the communications loop can extend from the control box across the boundary of a portal such as a door into a sealed enclosure into which access is restricted whereby the loop must be damaged or moved in order for an entry to be made into the enclosure. The device is adapted for detecting unauthorized entries into such enclosures such as rooms or containers and for recording the time at which such entries occur for later reference. Additionally, the device detects attempts to tamper or interfere with the operation of the device itself and records the time at which such events take place. In the preferred embodiment, the security device includes a microprocessor-based electronic system and a detection module capable of registering changes in the voltage and phase of the signal transmitted over the loop. 11 figs

BRAKE DEVICE

Science.gov (United States)

O'Donnell, T.J.

1959-03-10

A brake device is described for utilization in connection with a control rod. The device comprises a pair of parallelogram link mechanisms, a control rod moveable rectilinearly therebetween in opposite directions, and shoes resiliently supported by the mechanism for frictional engagement with the control rod.

Three fundamental devices in one: a reconfigurable multifunctional device in two-dimensional WSe2

Science.gov (United States)

Dhakras, Prathamesh; Agnihotri, Pratik; Lee, Ji Ung

2017-06-01

The three pillars of semiconductor device technologies are (1) the p-n diode, (2) the metal-oxide-semiconductor field-effect transistor and (3) the bipolar junction transistor. They have enabled the unprecedented growth in the field of information technology that we see today. Until recently, the technological revolution for better, faster and more efficient devices has been governed by scaling down the device dimensions following Moore’s Law. With the slowing of Moore’s law, there is a need for alternative materials and computing technologies that can continue the advancement in functionality. Here, we describe a single, dynamically reconfigurable device that implements these three fundamental device functions. The device uses buried gates to achieve n- and p-channels and fits into a larger effort to develop devices with enhanced functionalities, including logic functions, over device scaling. As they are all surface conducting devices, we use one material parameter, the interface trap density of states, to describe the key figure-of-merit of each device.

Investigating Mesoscale Convective Systems and their Predictability Using Machine Learning

Science.gov (United States)

Daher, H.; Duffy, D.; Bowen, M. K.

2016-12-01

A mesoscale convective system (MCS) is a thunderstorm region that lasts several hours long and forms near weather fronts and can often develop into tornadoes. Here we seek to answer the question of whether these tornadoes are "predictable" by looking for a defining characteristic(s) separating MCSs that evolve into tornadoes versus those that do not. Using NASA's Modern Era Retrospective-analysis for Research and Applications 2 reanalysis data (M2R12K), we apply several state of the art machine learning techniques to investigate this question. The spatial region examined in this experiment is Tornado Alley in the United States over the peak tornado months. A database containing select variables from M2R12K is created using PostgreSQL. This database is then analyzed using machine learning methods such as Symbolic Aggregate approXimation (SAX) and DBSCAN (an unsupervised density-based data clustering algorithm). The incentive behind using these methods is to mathematically define a MCS so that association rule mining techniques can be used to uncover some sort of signal or teleconnection that will help us forecast which MCSs will result in tornadoes and therefore give society more time to prepare and in turn reduce casualties and destruction.

Devices, Distractions and Digital Literacy: "Bring Your Own Device" to Polytech

Science.gov (United States)

Drew, Leoni; Forbes, Dianne

2017-01-01

The purpose of this study is to investigate the ways polytechnic students use personal mobile devices to support their learning. This study used purposive sampling and mixed methods to generate data about student ownership and use of mobile digital devices within a single institution. Findings reveal patterns of device ownership, insights into how…

Ion trap device

Science.gov (United States)

Ibrahim, Yehia M.; Smith, Richard D.

2016-01-26

An ion trap device is disclosed. The device includes a series of electrodes that define an ion flow path. A radio frequency (RF) field is applied to the series of electrodes such that each electrode is phase shifted approximately 180 degrees from an adjacent electrode. A DC voltage is superimposed with the RF field to create a DC gradient to drive ions in the direction of the gradient. A second RF field or DC voltage is applied to selectively trap and release the ions from the device. Further, the device may be gridless and utilized at high pressure.

Metallic spintronic devices

CERN Document Server

Wang, Xiaobin

2014-01-01

Metallic Spintronic Devices provides a balanced view of the present state of the art of metallic spintronic devices, addressing both mainstream and emerging applications from magnetic tunneling junction sensors and spin torque oscillators to spin torque memory and logic. Featuring contributions from well-known and respected industrial and academic experts, this cutting-edge work not only presents the latest research and developments but also: Describes spintronic applications in current and future magnetic recording devicesDiscusses spin-transfer torque magnetoresistive random-access memory (STT-MRAM) device architectures and modelingExplores prospects of STT-MRAM scaling, such as detailed multilevel cell structure analysisInvestigates spintronic device write and read optimization in light of spintronic memristive effectsConsiders spintronic research directions based on yttrium iron garnet thin films, including spin pumping, magnetic proximity, spin hall, and spin Seebeck effectsProposes unique solutions for ...

Sealing devices

International Nuclear Information System (INIS)

Coulson, R.A.

1980-01-01

A sealing device for minimising the leakage of toxic or radioactive contaminated environments through a biological shield along an opening through which a flexible component moves that penetrates the shield. The sealing device comprises an outer tubular member which extends over a length not less than the maximum longitudinal movement of the component along the opening. An inner sealing block is located intermediate the length of the component by connectors and is positioned in the bore of the outer tubular member to slide in the bore and effect a seal over the entire longitudinal movement of the component. The cross-section of the device may be circular and the block may be of polytetrafluoroethylene or of nylon impregnated with molybdenum or may be metallic. A number of the sealing devices may be combined into an assembly for a plurality of adjacent longitudinally movable components, each adapted to sustain a tensile load, providing the various drives of a master-slave manipulator. (author)

Delay reduction in multi-hop device-to-device communication using network coding

KAUST Repository

Douik, Ahmed S.; Sorour, Sameh; Al-Naffouri, Tareq Y.; Yang, Hong-Chuan; Alouini, Mohamed-Slim

2015-01-01

This paper considers the problem of reducing the broadcast delay of wireless networks using instantly decodable network coding (IDNC) based device-to-device (D2D) communications. In D2D-enabled networks, devices help hasten the recovery of the lost

Temperature indicating device

International Nuclear Information System (INIS)

Angus, J.P.; Salt, D.

1988-01-01

A temperature indicating device comprises a plurality of planar elements some undergoing a reversible change in appearance at a given temperature the remainder undergoing an irreversible change in appearance at a given temperature. The device is useful in indicating the temperature which an object has achieved as well as its actual temperature. The reversible change is produced by liquid crystal devices. The irreversible change is produced by an absorbent surface carrying substances e.g. waxes which melt at predetermined temperatures and are absorbed by the surface; alternatively paints may be used. The device is used for monitoring processes of encapsulation of radio active waste. (author)

Thermal energy storage devices, systems, and thermal energy storage device monitoring methods

Science.gov (United States)

Tugurlan, Maria; Tuffner, Francis K; Chassin, David P.

2016-09-13

Thermal energy storage devices, systems, and thermal energy storage device monitoring methods are described. According to one aspect, a thermal energy storage device includes a reservoir configured to hold a thermal energy storage medium, a temperature control system configured to adjust a temperature of the thermal energy storage medium, and a state observation system configured to provide information regarding an energy state of the thermal energy storage device at a plurality of different moments in time.

EPICS GPIB device support

International Nuclear Information System (INIS)

Winans, J.

1993-01-01

A GPIB device support module is used to provide access to the operating parameters of a GPIB device. GPIB devices may be accessed via National Instruments 1014 cards or via Bitbus Universal Gateways. GPIB devices typically have many parameters, each of which may be thought of in terms of the standard types of database records available in EPICS. It is the job of the device support module designer to decide how the mapping of these parameters will be made to the available record types. Once this mapping is complete, the device support module may be written. The writing of the device support module consists primarily of the construction of a parameter table. This table is used to associate the database record types with the operating parameters of the GPIB instrument. Other aspects of module design include the handling of SRQ events and errors. SRQ events are made available to the device support module if so desired. The processing of an SRQ event is completely up to the designer of the module. They may be ignored, tied to event based record processing, or anything else the designer wishes. Error conditions may be handled in a similar fashion

Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices

Energy Technology Data Exchange (ETDEWEB)

Lijuan Zou

2003-08-05

Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm{sup 2}, the optimal radiance R could reach 0.38 mW/cm{sup 2}, and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be {approx} 10{sup -5} cm{sup 2}/Vs and {approx} 10{sup -4} cm{sup 2}/Vs, respectively. Overshoot effects in the transient El of blue light emitting devices were also observed and studied. This effect was attributed to the charge accumulation at the organic/organic and organic/cathode interfaces.

Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices

International Nuclear Information System (INIS)

Lijuan Zou

2003-01-01

Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm 2 , the optimal radiance R could reach 0.38 mW/cm 2 , and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be ∼ 10 -5 cm 2 /Vs and ∼ 10 -4 cm 2 /Vs, respectively. Overshoot effects in the transient El of blue light emitting devices were also observed and studied. This effect was attributed to the charge accumulation at the organic/organic and organic/cathode interfaces

77 FR 51571 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers...

Science.gov (United States)

2012-08-24

... Music and Data Processing Devices, Computers, and Components Thereof; Notice of Receipt of Complaint... complaint entitled Wireless Communication Devices, Portable Music and Data Processing Devices, Computers..., portable music and data processing devices, computers, and components thereof. The complaint names as...

Integrated control rod monitoring device

International Nuclear Information System (INIS)

Saito, Katsuhiro

1997-01-01

The present invention provides a device in which an entire control rod driving time measuring device and a control rod position support device in a reactor building and a central control chamber are integrated systematically to save hardwares such as a signal input/output device and signal cables between boards. Namely, (1) functions of the entire control rod driving time measuring device for monitoring control rods which control the reactor power and a control rod position indication device are integrated into one identical system. Then, the entire devices can be made compact by the integration of the functions. (2) The functions of the entire control rod driving time measuring device and the control rod position indication device are integrated in a central operation board and a board in the site. Then, the place for the installation of them can be used in common in any of the cases. (3) The functions of the entire control rod driving time measuring device and the control rod position indication device are integrated to one identical system to save hardware to be used. Then, signal input/output devices and drift branching panel boards in the site and the central operation board can be saved, and cables for connecting both of the boards is no more necessary. (I.S.)

76 FR 45860 - In the Matter of Certain Electronic Devices, Including Wireless Communication Devices, Portable...

Science.gov (United States)

2011-08-01

..., Including Wireless Communication Devices, Portable Music and Data Processing Devices, and Tablet Computers... electronic devices, including wireless communication devices, portable music and data processing devices, and...''). The complaint further alleges that an industry in the United States exists or is in the process of...

Medical devices; exemption from premarket notification; class II devices; wheelchair elevator. Final order.

Science.gov (United States)

2013-03-04

The Food and Drug Administration (FDA) is publishing an order granting a petition requesting exemption from premarket notification requirements for wheelchair elevator devices commonly known as inclined platform lifts and vertical platform lifts. These devices are used to provide a means for a person with a mobility impairment caused by injury or other disease to move from one level to another, usually in a wheelchair. This order exempts wheelchair elevators, class II devices, from premarket notification and establishes conditions for exemption for this device that will provide a reasonable assurance of the safety and effectiveness of the device without submission of a premarket notification (510(k)). This exemption from 510(k), subject to these conditions, is immediately in effect for wheelchair elevators. All other devices classified under FDA's wheelchair elevator regulations, including attendant-operated stair climbing devices for wheelchairs and portable platform lifts, continue to require submission of 510(k)s. FDA is publishing this order in accordance with the section of the Food, Drug, and Cosmetic Act (the FD&C Act) permitting the exemption of a device from the requirement to submit a 510(k).

Fusion devices

International Nuclear Information System (INIS)

Fowler, T.K.

1977-01-01

Three types of thermonuclear fusion devices currently under development are reviewed for an electric utilities management audience. Overall design features of laser fusion, tokamak, and magnetic mirror type reactors are described and illustrated. Thrusts and trends in current research on these devices that promise to improve performance are briefly reviewed. Twenty photographs and drawings are included

High voltage MOSFET devices and methods of making the devices

Science.gov (United States)

Banerjee, Sujit; Matocha, Kevin; Chatty, Kiran

2018-06-05

A SiC MOSFET device having low specific on resistance is described. The device has N+, P-well and JFET regions extended in one direction (Y-direction) and P+ and source contacts extended in an orthogonal direction (X-direction). The polysilicon gate of the device covers the JFET region and is terminated over the P-well region to minimize electric field at the polysilicon gate edge. In use, current flows vertically from the drain contact at the bottom of the structure into the JFET region and then laterally in the X direction through the accumulation region and through the MOSFET channels into the adjacent N+ region. The current flowing out of the channel then flows along the N+ region in the Y-direction and is collected by the source contacts and the final metal. Methods of making the device are also described.

High voltage MOSFET devices and methods of making the devices

Science.gov (United States)

Banerjee, Sujit; Matocha, Kevin; Chatty, Kiran

2015-12-15

A SiC MOSFET device having low specific on resistance is described. The device has N+, P-well and JFET regions extended in one direction (Y-direction) and P+ and source contacts extended in an orthogonal direction (X-direction). The polysilicon gate of the device covers the JFET region and is terminated over the P-well region to minimize electric field at the polysilicon gate edge. In use, current flows vertically from the drain contact at the bottom of the structure into the JFET region and then laterally in the X direction through the accumulation region and through the MOSFET channels into the adjacent N+ region. The current flowing out of the channel then flows along the N+ region in the Y-direction and is collected by the source contacts and the final metal. Methods of making the device are also described.

Fuel pattern recognition device

International Nuclear Information System (INIS)

Sato, Tomomi.

1995-01-01

The device of the present invention monitors normal fuel exchange upon fuel exchanging operation carried out in a reactor of a nuclear power plant. Namely, a fuel exchanger is movably disposed to the upper portion of the reactor and exchanges fuels. An exclusive computer receives operation signals of the fuel exchanger during operation as inputs, and outputs reactor core fuel pattern information signals to a fuel arrangement diagnosis device. An underwater television camera outputs image signals of a fuel pattern in the reactor core to an image processing device. If there is any change in the image signals for the fuel pattern as a result of the fuel exchange operation of the fuel exchanger, the image processing device outputs the change as image signals to the fuel pattern diagnosis device. The fuel pattern diagnosis device compares the pattern information signals from the exclusive computer with the image signals from the image processing device, to diagnose the result of the fuel exchange operation performed by the fuel exchanger and inform the diagnosis by means of an image display. (I.S.)

77 FR 58576 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers...

Science.gov (United States)

2012-09-21

... Devices, Portable Music and Data Processing Devices, Computers, and Components Thereof; Institution of... communication devices, portable music and data processing devices, computers, and components thereof by reason... alleges that an industry in the United States exists as required by subsection (a)(2) of section 337. The...

Firewood preparation devices in 1994

International Nuclear Information System (INIS)

Mutikainen, A.

1994-01-01

A review of the market situation regarding firewood preparation devices is presented. The information was collected from the answers to a mail questionnaire. The review is assumed to include all the leading manufacturers and importers. Firewood production devices were available from 26 manufacturers. The range of models amounted to over 70. These may be divided into three categories: 1. cutting devices: the most common solution being a cross-cutting circular saw. There were only a few of these on sale as it is quite easy to include a splitting device on the same frame. 2. Splitting devices: e.g. screw splitter and hydraulically powered splitter. About 20 models are available on the markets. Cross cutting and splitting devices: these are the most popular devices. A cross-cutting circular saw with screw or hydraulic splitter is the most common type. There are about 50 models available on the markets. Cross-cutting and splitting devices are often equipped with conveyor for transferring the split wood e.g. into a trailer. Chopping devices are delivered as tractor powered devices, as electric motor powered devices or as combustion engine powered devices. Some of them are equipped with a time saving feeding device enabling the next stem to be lifted into position while the previous one is being chopped. The Finnish Work Efficiency Institute's studies show that when cross-cutting and splitting of stems into pieces of 35-50 cm in length, productivity for one operator varies in between 0.8 - 3.2 m 3 /h, depending on the device and work method used. (6 refs., 1 fig., 2 tabs.)

Flaw detection device

International Nuclear Information System (INIS)

Sasahara, Toshihiko

1998-01-01

The present invention provides a device for detecting welded portions of a reactor pressure vessel. Namely, the device of the present invention comprises (1) a casing to be disposed on the surface to be detected, (2) a probe driving means loaded to the casing, (3) a probe driven along the surface to be detected and (4) a pressure reduction means for keeping the hollow portion in the casing to an evacuated atmosphere. The casing comprises a flexible suction edge to be tightly in contact with the surface to be tested for maintaining the air tight state, (6) a guide wheel for moving the casing along the surface to be tested and (7) a handle for performing transferring operation. The flaw detection device thus constituted has following features. The working efficiency upon conducting detection is improved. The influence of the weight of the device on the detection is small. The device can be applied on the surface of a nonmagnetic material. The efficiency for the flaw detection can be improved. (I.S.)

Fuel inspection device

International Nuclear Information System (INIS)

Tsuji, Tadashi.

1990-01-01

The fuel inspection device of the present invention has a feature of obtaining an optimum illumination upon fuel rod interval inspection operation in a fuel pool. That is, an illumination main body used underwater is connected to a cable which is led out on a floor. A light control device is attached to the other end of the cable and an electric power cable is connected to the light control device. A light source (for example, incandescent lamp) is incorporated in the casing of the illumination main body, and a diffusion plate is disposed at the front to provide a plane light source. The light control device has a light control knob capable of remote-controlling the brightness of the light of the illumination main body. In the fuel inspection device thus constituted, halation is scarcely caused on the image screen upon inspection of fuels by a submerged type television camera to facilitate control upon inspection. Accordingly, efficiency of the fuel inspection can be improved to shorten the operation time. (I.S.)

Medical Devices; Immunology and Microbiology Devices; Classification of the Device To Detect and Identify Microbial Pathogen Nucleic Acids in Cerebrospinal Fluid. Final order.

Science.gov (United States)

2017-10-20

The Food and Drug Administration (FDA or we) is classifying the device to detect and identify microbial pathogen nucleic acids in cerebrospinal fluid into class II (special controls). The special controls that will apply to the device type are identified in this order and will be part of the codified language for the device to detect and identify microbial pathogen nucleic acids in cerebrospinal fluid’s classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

Smart devices are different

DEFF Research Database (Denmark)

Stisen, Allan; Blunck, Henrik; Bhattacharya, Sourav

2015-01-01

research results. This is due to variations in training and test device hardware and their operating system characteristics among others. In this paper, we systematically investigate sensor-, device- and workload-specific heterogeneities using 36 smartphones and smartwatches, consisting of 13 different...... device models from four manufacturers. Furthermore, we conduct experiments with nine users and investigate popular feature representation and classification techniques in HAR research. Our results indicate that on-device sensor and sensor handling heterogeneities impair HAR performances significantly...

Rooting an Android Device

Science.gov (United States)

2015-09-01

1. Overview The purpose of this document is to demonstrate how to gain administrative privileges on an Android device. The term “rooting” is...is applicable for the Samsung Galaxy S3 as well as many other Android devices, but there are several steps involved in rooting an Android device (as...root access has been granted. 4. Conclusion This document serves as a tutorial on how to grant user administrative privilege to an Android device by

Novel Magnetic Devices

National Research Council Canada - National Science Library

Schuller, Ivan

2007-01-01

...: ballistic magnetoresistance, magnetic field proximity effect and spin drag. These three phenomena would then be exploited for the design of novel device architectures and to investigate the physical principles behind these devices...

Evaluating imaging devices

International Nuclear Information System (INIS)

Rollo, F.D.

1977-01-01

The performance of any imaging device depends on two principal factors inherent to the device, namely, plane sensitivity and spatial resolution. These factors may be defined as follows: plane sensitivity is the counts per second recorded by the imaging device for each disintegration per second per square centimeter occurring within a plane sheet of radioactivity. Spatial resolution may be defined as the fidelity with which the imaging device reproduces the activity distribution of an object in the image plane. In all imaging devices, a trade-off exists between these two parameters; that is, as sensitivity improves, spatial resolution is degraded, and vice versa. Therefore, to fully evaluate an imaging system a technique should be selected that measures both parameters and reflects the trade-off between the two. In addition, the method should approximate the clinical problem, namely, the detection of a focal lesion within an activity distribution. Several methods have been described to evaluate nuclear imaging devices. The more common techniques include the use of organ phantoms, bar phantoms, line-spread functions, modulation transfer functions, contrast efficiency functions, and performance index functions. Each of these techniques is briefly described in this chapter, and their advantages and disadvantages are discussed. In addition, a phantom that can be used to simply and completely measure overall imaging system performance is described

Ergonomic material-handling device

Science.gov (United States)

Barsnick, Lance E.; Zalk, David M.; Perry, Catherine M.; Biggs, Terry; Tageson, Robert E.

2004-08-24

A hand-held ergonomic material-handling device capable of moving heavy objects, such as large waste containers and other large objects requiring mechanical assistance. The ergonomic material-handling device can be used with neutral postures of the back, shoulders, wrists and knees, thereby reducing potential injury to the user. The device involves two key features: 1) gives the user the ability to adjust the height of the handles of the device to ergonomically fit the needs of the user's back, wrists and shoulders; and 2) has a rounded handlebar shape, as well as the size and configuration of the handles which keep the user's wrists in a neutral posture during manipulation of the device.

Materials for electrochemical device safety

Science.gov (United States)

Vissers, Daniel R.; Amine, Khalil; Thackeray, Michael M.; Kahaian, Arthur J.; Johnson, Christopher S.

2015-04-07

An electrochemical device includes a thermally-triggered intumescent material or a gas-triggered intumescent material. Such devices prevent or minimize short circuits in a device that could lead to thermal run-away. Such devices may include batteries or supercapacitors.

A seasonal-scale climatological analysis correlating spring tornadic activity with antecedent fall-winter drought in the southeastern United States

International Nuclear Information System (INIS)

Shepherd, Marshall; Mote, Thomas L; Niyogi, Dev

2009-01-01

Using rain gauge and satellite-based rainfall climatologies and the NOAA Storm Prediction Center tornado database (1952-2007), this study found a statistically significant tendency for fall-winter drought conditions to be correlated with below-normal tornado days the following spring in north Georgia (i.e. 93% of the years) and other regions of the Southeast. Non-drought years had nearly twice as many tornado days in the study area as drought years and were also five to six times more likely to have multiple tornado days. Individual tornadic events are largely a function of the convective-mesoscale thermodynamic and dynamic environments, thus the study does not attempt to overstate predictability. Yet, the results may provide seasonal guidance in an analogous manner to the well known Sahelian rainfall and Cape Verde hurricane activity relationships.

Heterostructures and quantum devices

CERN Document Server

Einspruch, Norman G

1994-01-01

Heterostructure and quantum-mechanical devices promise significant improvement in the performance of electronic and optoelectronic integrated circuits (ICs). Though these devices are the subject of a vigorous research effort, the current literature is often either highly technical or narrowly focused. This book presents heterostructure and quantum devices to the nonspecialist, especially electrical engineers working with high-performance semiconductor devices. It focuses on a broad base of technical applications using semiconductor physics theory to develop the next generation of electrical en

Plasma shutdown device

International Nuclear Information System (INIS)

Hosogane, Nobuyuki; Nakayama, Takahide.

1985-01-01

Purpose: To prevent concentration of plasma currents to the plasma center upon plasma shutdown in a torus type thermonuclear device by the injection of fuels to the plasma center thereby prevent plasma disruption at the plasma center. Constitution: The plasma shutdown device comprises a plasma current measuring device that measures the current distribution of plasmas confined within a vacuum vessel and outputs a control signal for cooling the plasma center when the plasma currents concentrate to the plasma center and a fuel supply device that supplies fuels to the plasma center for cooling the center. The fuels are injected in the form of pellets into the plasmas. The direction and the velocity of the injection are set such that the pellets are ionized at the center of the plasmas. (Horiuchi, T.)

Photovoltaic device and method

Science.gov (United States)

Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

2015-01-27

The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

Magnet-assisted device-level alignment for the fabrication of membrane-sandwiched polydimethylsiloxane microfluidic devices

International Nuclear Information System (INIS)

Lu, J-C; Liao, W-H; Tung, Y-C

2012-01-01

Polydimethylsiloxane (PDMS) microfluidic device is one of the most essential techniques that advance microfluidics research in recent decades. PDMS is broadly exploited to construct microfluidic devices due to its unique and advantageous material properties. To realize more functionalities, PDMS microfluidic devices with multi-layer architectures, especially those with sandwiched membranes, have been developed for various applications. However, existing alignment methods for device fabrication are mainly based on manual observations, which are time consuming, inaccurate and inconsistent. This paper develops a magnet-assisted alignment method to enhance device-level alignment accuracy and precision without complicated fabrication processes. In the developed alignment method, magnets are embedded into PDMS layers at the corners of the device. The paired magnets are arranged in symmetric positions at each PDMS layer, and the magnetic attraction force automatically pulls the PDMS layers into the aligned position during assembly. This paper also applies the method to construct a practical microfluidic device, a tunable chaotic micromixer. The results demonstrate the successful operation of the device without failure, which suggests the accurate alignment and reliable bonding achieved by the method. Consequently, the fabrication method developed in this paper is promising to be exploited to construct various membrane-sandwiched PDMS microfluidic devices with more integrated functionalities to advance microfluidics research. (paper)

Hot gas handling device and motorized vehicle comprising the device

NARCIS (Netherlands)

Klein Geltink, J.; Beukers, A.; Van Tooren, M.J.L.; Koussios, S.

2012-01-01

The invention relates to a device for handling hot exhaust gasses discharged from an internal combustion engine. The device comprises a housing (2), enclosing a space (3) for transporting the exhaust gasses. The housing (2) is provided with an entrance - opening (4) for the exhaust gasses discharged

Implantable Medical Devices

Science.gov (United States)

... Artery Disease Venous Thromboembolism Aortic Aneurysm More Implantable Medical Devices Updated:Sep 16,2016 For Rhythm Control ... a Heart Attack Introduction Medications Surgical Procedures Implantable Medical Devices • Life After a Heart Attack • Heart Attack ...

Output hardcopy devices

CERN Document Server

Durbeck, Robert

1988-01-01

Output Hardcopy Devices provides a technical summary of computer output hardcopy devices such as plotters, computer output printers, and CRT generated hardcopy. Important related technical areas such as papers, ribbons and inks, color techniques, controllers, and character fonts are also covered. Emphasis is on techniques primarily associated with printing, as well as the plotting capabilities of printing devices that can be effectively used for computer graphics in addition to their various printing functions. Comprised of 19 chapters, this volume begins with an introduction to vector and ras

Powering biomedical devices

CERN Document Server

Romero, Edwar

2013-01-01

From exoskeletons to neural implants, biomedical devices are no less than life-changing. Compact and constant power sources are necessary to keep these devices running efficiently. Edwar Romero's Powering Biomedical Devices reviews the background, current technologies, and possible future developments of these power sources, examining not only the types of biomedical power sources available (macro, mini, MEMS, and nano), but also what they power (such as prostheses, insulin pumps, and muscular and neural stimulators), and how they work (covering batteries, biofluids, kinetic and ther

78 FR 24775 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers and...

Science.gov (United States)

2013-04-26

... Devices, Portable Music and Data Processing Devices, Computers and Components Thereof; Commission Decision... importation of certain wireless communication devices, portable music and data processing devices, computers... '826 patent''). The complaint further alleges the existence of a domestic industry. The Commission's...

77 FR 38826 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers and...

Science.gov (United States)

2012-06-29

... Devices, Portable Music and Data Processing Devices, Computers and Components Thereof, Commission Decision... importation of certain wireless communication devices, portable music and data processing devices, computers... further alleges the existence of a domestic industry. The Commission's notice of investigation named Apple...

78 FR 12785 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers and...

Science.gov (United States)

2013-02-25

... Devices, Portable Music and Data Processing Devices, Computers and Components Thereof; Commission Decision... importation of certain wireless communication devices, portable music and data processing devices, computers... further alleges the existence of a domestic industry. The Commission's notice of investigation named Apple...

Humanitarian Use Device and Humanitarian Device Exemption regulatory programs: pros and cons.

Science.gov (United States)

Bernad, Daniel Maxwell

2009-03-01

The US FDA established the Humanitarian Use Device (HUD) and Humanitarian Device Exemption (HDE) program to encourage medical device firms to address rare diseases. Despite being in existence for over a decade, there has only been one peer-reviewed publication examining this field. The objective of this report is to investigate how the HUD/HDE program differs from the standard regulatory system, discuss its potential advantages and disadvantages, and to speculate which humanitarian devices will be brought to market within the next 5 years. A total of 40 semistructured interviews with stakeholders, representing approximately half (n = 20, 49%) of the firms that have successfully obtained HDE-approved products, were performed in order to acquire the primary data for this paper. There appear to be short-term gains and long-term drains associated with launching humanitarian devices to market. This report aims to provide sponsors with information that may allow them to make better decisions during their product development of humanitarian devices and may, hopefully, also play a role in encouraging other sponsors to take the necessary steps forward in helping to find treatments for patients with rare diseases.

77 FR 14272 - Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus Serological...

Science.gov (United States)

2012-03-09

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 866 [Docket No. FDA-2012-N-0165] Medical Devices; Immunology and Microbiology Devices; Classification of Norovirus... AND MICROBIOLOGY DEVICES 0 1. The authority citation for 21 CFR part 866 continues to read as follows...

21 CFR 882.5050 - Biofeedback device.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Biofeedback device. 882.5050 Section 882.5050 Food... DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5050 Biofeedback device. (a) Identification. A biofeedback device is an instrument that provides a visual or auditory signal corresponding to...

77 FR 52759 - Certain Wireless Communication Devices, Portable Music and Data Processing Devices, Computers and...

Science.gov (United States)

2012-08-30

... Devices, Portable Music and Data Processing Devices, Computers and Components Thereof; Notice of... communication devices, portable music and data processing devices, computers and components thereof by reason of... complaint further alleges the existence of a domestic industry. The Commission's notice of investigation...