WorldWideScience

Sample records for shock phenomena experienced

  1. Molecular dynamics simulation of laser shock phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Fukumoto, Ichirou [Japan Atomic Energy Research Inst., Kansai Research Establishment, Advanced Photon Research Center, Neyagawa, Osaka (Japan).

    2001-10-01

    Recently, ultrashort-pulse lasers with high peak power have been developed, and their application to materials processing is expected as a tool of precision microfabrication. When a high power laser irradiates, a shock wave propagates into the material and dislocations are generated. In this paper, laser shock phenomena of the metal were analyzed using the modified molecular dynamics method, which has been developed by Ohmura and Fukumoto. The main results obtained are summarized as follows: (1) The shock wave induced by the Gaussian beam irradiation propagates radially from the surface to the interior. (2) A lot of dislocations are generated at the solid-liquid interface by the propagation of a shock wave. (3) Some dislocations are moved instantaneously with the velocity of the longitudinal wave when the shock wave passes, and their velocity is not larger than the transverse velocity after the shock wave has passed. (author)

  2. High Temperature Phenomena in Shock Waves

    CERN Document Server

    2012-01-01

    The high temperatures generated in gases by shock waves give rise to physical and chemical phenomena such as molecular vibrational excitation, dissociation, ionization, chemical reactions and inherently related radiation. In continuum regime, these processes start from the wave front, so that generally the gaseous media behind shock waves may be in a thermodynamic and chemical non-equilibrium state. This book presents the state of knowledge of these phenomena. Thus, the thermodynamic properties of high temperature gases, including the plasma state are described, as well as the kinetics of the various chemical phenomena cited above. Numerous results of measurement and computation of vibrational relaxation times, dissociation and reaction rate constants are given, and various ionization and radiative mechanisms and processes are presented. The coupling between these different phenomena is taken into account as well as their interaction with the flow-field. Particular points such as the case of rarefied flows an...

  3. Investigation of oscillating airfoil shock phenomena

    OpenAIRE

    Giordano , Daniel; Fleeter , Sanford

    1992-01-01

    Fundamental experiments were performed in an unsteady flow water table facility to investigate and quantify the unsteady aerodynamics of a biconvex airfoil executing torsion mode oscillations at realistic reduced frequencies. A computer-based image enhancement system was used to measure the oscillating supersonic and transonic shock flow phenomena. By utilizing the hydraulic analogy to compare experimental results with a linear theoretical prediction, magnitude and phase relationships for the...

  4. Shock Wave Diffraction Phenomena around Slotted Splitters

    Directory of Open Access Journals (Sweden)

    Francesca Gnani

    2015-01-01

    Full Text Available In the field of aerospace engineering, the study of the characteristics of vortical flows and their unsteady phenomena finds numerous engineering applications related to improvements in the design of tip devices, enhancement of combustor performance, and control of noise generation. A large amount of work has been carried out in the analysis of the shock wave diffraction around conventional geometries such as sharp and rounded corners, but the employment of splitters with lateral variation has hardly attracted the attention of researchers. The investigation of this phenomenon around two-dimensional wedges has allowed the understanding of the basic physical principles of the flow features. On the other hand, important aspects that appear in the third dimension due to the turbulent nature of the vortices are omitted. The lack of studies that use three-dimensional geometries has motivated the current work to experimentally investigate the evolution of the shock wave diffraction around two splitters with spike-shaped structures for Mach numbers of 1.31 and 1.59. Schlieren photography was used to obtain an insight into the sequential diffraction processes that take place in different planes. Interacting among them, these phenomena generate a complicated turbulent cloud with a vortical arrangement.

  5. Interplanetary shock phenomena beyond 1 AU

    International Nuclear Information System (INIS)

    Smith, E.J.

    1985-01-01

    Attention is given to spatial dependences exhibited by spacecraft measurements obtained between 1 and 30 AU, together with temporal variations occurring between solar activity cycle maxima and minima. At 1-3 AU radial distances, shocks develop in association with the corotating solar wind streams characterizing solar minimum and accelerate solar wind evolution with distance while heating the solar wind and generating waves and turbulence. At solar maximum, shocks are observed more frequently at 1 AU but still in association with transient solar events; acceleration leading to energetic storm particles is observed both within and beyond 1 AU. The superimposed effect of large numbers of intense shocks may be responsible for the solar cycle modulation of galactic cosmic rays. 77 references

  6. Shock Tunnel Studies of Scramjet Phenomena 1993

    Science.gov (United States)

    Stalker, R. J.; Bakos, R. J.; Morgan, R. G.; Porter, L.; Mee, D.; Paull, A.; Tuttle, S.; Simmons, J. M.; Wendt, M.; Skinner, K.

    1995-01-01

    Reports by the staff of the University of Queensland on various research studies related to the advancement of scramjet technology and hypervelocity pulse test facilities are presented. These reports document the tests conducted in the reflected shock tunnel T4 and supporting research facilities that have been used to study the injection, mixing, and combustion of hydrogen fuel in generic scramjets at flow conditions typical of hypersonic flight. In addition, topics include the development of instrumentation and measurement technology, such as combustor wall shear and stream composition in pulse facilities, and numerical studies and analyses of the scramjet combustor process and the test facility operation. This research activity is Supplement 10 under NASA Grant NAGw-674.

  7. Shock Tube Ignition Delay Data Affected by Localized Ignition Phenomena

    KAUST Repository

    Javed, Tamour

    2016-12-29

    Shock tubes have conventionally been used for measuring high-temperature ignition delay times ~ O(1 ms). In the last decade or so, the operating regime of shock tubes has been extended to lower temperatures by accessing longer observation times. Such measurements may potentially be affected by some non-ideal phenomena. The purpose of this work is to measure long ignition delay times for fuels exhibiting negative temperature coefficient (NTC) and to assess the impact of shock tube non-idealities on ignition delay data. Ignition delay times of n-heptane and n-hexane were measured over the temperature range of 650 – 1250 K and pressures near 1.5 atm. Driver gas tailoring and long length of shock tube driver section were utilized to measure ignition delay times as long as 32 ms. Measured ignition delay times agree with chemical kinetic models at high (> 1100 K) and low (< 700 K) temperatures. In the intermediate temperature range (700 – 1100 K), however, significant discrepancies are observed between the measurements and homogeneous ignition delay simulations. It is postulated, based on experimental observations, that localized ignition kernels could affect the ignition delay times at the intermediate temperatures, which lead to compression (and heating) of the bulk gas and result in expediting the overall ignition event. The postulate is validated through simple representative computational fluid dynamic simulations of post-shock gas mixtures which exhibit ignition advancement via a hot spot. The results of the current work show that ignition delay times measured by shock tubes may be affected by non-ideal phenomena for certain conditions of temperature, pressure and fuel reactivity. Care must, therefore, be exercised in using such data for chemical kinetic model development and validation.

  8. Shock Tube Ignition Delay Data Affected by Localized Ignition Phenomena

    KAUST Repository

    Javed, Tamour; Badra, J.; Jaasim, Mohammed; Es-sebbar, Et-touhami; Labastida, M.F.; Chung, Suk-Ho; Im, Hong G.; Farooq, Aamir

    2016-01-01

    Shock tubes have conventionally been used for measuring high-temperature ignition delay times ~ O(1 ms). In the last decade or so, the operating regime of shock tubes has been extended to lower temperatures by accessing longer observation times

  9. Computational and experimental investigation of dynamic shock reflection phenomena

    CSIR Research Space (South Africa)

    Naidoo, K

    2007-07-01

    Full Text Available wedge are used to analyse dynamic flow field phenomena and response of the triple point below and within the dual solution domain. Computed, unsteady pressure traces on the reflection plane are also analysed...

  10. Investigation of Surface Phenomena in Shocked Tin in Converging Geometry

    Energy Technology Data Exchange (ETDEWEB)

    Rousculp, Christopher L. [Los Alamos National Laboratory; Oro, David Michael [Los Alamos National Laboratory; Griego, Jeffrey Randall [Los Alamos National Laboratory; Turchi, Peter John [Los Alamos National Laboratory; Reinovsky, Robert Emil [Los Alamos National Laboratory; Bradley, Joseph Thomas [Los Alamos National Laboratory; Cheng, Baolian [Los Alamos National Laboratory; Freeman, Matthew Stouten [Los Alamos National Laboratory; Patten, Austin Randall [Los Alamos National Laboratory

    2016-03-21

    There is great interest in the behavior of the free surface of tin under shock loading. While it is known that meso-scale surface imperfections can seed the Richtmyer- Meshkov Instability (RMI) for a surface that is melted on release, much less is known about a tin surface that is solid, but plastically deforming. Here material properties such as shear and yield strength come into play especially in converging geometry. Previous experiments have been driven by direct contact HE. Usually a thin, flat target coupon is fielded with various single-mode, sinusoidal, machined, profiles on the free surface. The free surface is adjacent to either vacuum or an inert receiver gas. Most of these previous driver/target configurations have been nominal planer geometry. With modern HE it has been straightforward to shock tin into melt on release. However it has been challenging to achieve a low enough pressure for solid state on release. Here we propose to extend the existing base of knowledge to include the behavior of the free surface of tin in cylindrical converging geometry. By shock loading a cylindrical tin shell with a magnetically driven cylindrical liner impactor, the free surface evolution can be diagnosed with proton radiography. With the PHELIX capacitor bank, the drive can easily be varied to span the pressure range to achieve solid, mixed, and liquid states on release. A conceptual cylindrical liner and target is shown in Figure 1.

  11. Comparison of shock transmission and forearm electromyography between experienced and recreational tennis players during backhand strokes.

    Science.gov (United States)

    Wei, Shun-Hwa; Chiang, Jinn-Yen; Shiang, Tzyy-Yuang; Chang, Hsiao-Yun

    2006-03-01

    To test the hypothesis that recreational tennis players transmit more shock impact from the racket to the elbow joint than experienced tennis players during the backhand stroke. Also, to test whether recreational tennis players used higher electromyographic (EMG) activities in common wrist extensor and flexor around epicondylar region at follow-through phase. A repeated-measure, cross-sectional study. National College of Physical Education and Sports at Taipei, Taiwan. Twenty-four male tennis players with no abnormal forearm musculoskeletal injury participated in the study. According to performance level, subjects were categorized into 2 groups: experienced and recreational. Impact transmission and wrist extensor-flexor EMG for backhand acceleration, impact, and follow-through phases were recorded for each player. An independent t test with a significance level of 0.05 was used to examine mean differences of shock impact and EMG between the 2 test groups. One-way ANOVA associated with Tukey multiple comparisons was used to identify differences among different impact locations and EMG phases. Experienced athletes reduced the racket impact to the elbow joint by 89.2%, but recreational players reduced it by only 61.8%. The largest EMG differences were found in the follow-through phase (Pelbow joint and use larger wrist flexor and extensor EMG activities at follow-through phase of the backhand stroke. Follow-through control is proposed as a critical factor for reduction of shock transmission. Clinicians or trainers should instruct beginners to quickly release their grip tightness after ball-to-racket impact to reduce shock impact transmission to the wrist and elbow.

  12. Measurement and Analysis of the Extreme Physical Shock Environment Experienced by Crane-Mounted Radiation Detection Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, M [Texas A & M Univ., College Station, TX (United States); Erchinger, J [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Marianno, C [Texas A & M Univ., College Station, TX (United States); Kallenbach, Gene A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Grypp, M [US Dept. of the Navy

    2017-09-01

    Potentially, radiation detectors at ports of entry could be mounted on container gantry crane spreaders to monitor cargo containers entering and leaving the country. These detectors would have to withstand the extreme physical environment experienced by these spreaders during normal operations. Physical shock data from the gable ends of a spreader were recorded during the loading and unloading of a cargo ship with two Lansmont SAVER 9X30 units (with padding) and two PCB Piezotronics model 340A50 accelerometers (hard mounted). Physical shocks in the form of rapid acceleration were observed in all accelerometer units with values ranging from 0.20 g’s to 199.99 g’s. The majority of the shocks for all the Lansmont and PCB accelerometers were below 50 g’s. The Lansmont recorded mean shocks of 21.83 ± 13.62 g’s and 24.78 ± 11.49 g’s while the PCB accelerometers experienced mean shocks of 34.39 ± 25.51 g’s and 41.77 ± 22.68 g’s for the landside and waterside units, respectively. Encased detector units with external padding should be designed to withstand at least 200 g’s of acceleration without padding and typical shocks of 30 g’s with padding for mounting on a spreader.

  13. The healthcare utilization and cost of treating patients experiencing inappropriate implantable cardioverter defibrillator shocks: a propensity score study.

    Science.gov (United States)

    Bhavnani, Sanjeev P; Giedrimiene, Dalia; Coleman, Craig I; Guertin, Danette; Azeem, Meena; Kluger, Jeffrey

    2014-10-01

    Inappropriate shocks (IASs) from implantable cardioverter defibrillators (ICDs) are associated with decreased quality of life, but whether they increase healthcare utilization and treatment costs is unknown. We sought to determine the impact of IASs on subsequent healthcare utilization and treatment costs. We conducted a case-control analysis of ICD patients at a single institution from 1997 to 2010 and who had ≥12 months of post-ICD implant follow-up. Cases included all patients experiencing an IAS during the first 12 months after implantation. Eligible control patients did not receive a shock of any kind during the 12 months after implantation. Propensity scores based on 36 covariates (area under curve = 0.78) were used to match cases to controls. We compared the rate (occurrences/person year [PY]) of healthcare utilization immediately following IAS to the end of the 12-month follow-up period to the rate in the no-shock group over 12 months of follow-up. We also compared 12-month postimplant treatment (outpatient clinic, emergency room, and hospitalization) costs in both groups. A total of 76 patients experiencing ≥1 IAS during the first 12 months after implant (contributing 48 PYs) were matched to 76 no-shock patients (contributing 76 PYs). Cardiovascular (CV)-related clinic visit and hospitalization rates were increased following an IAS compared to those not receiving a shock (4.0 vs 3.3 and 0.7 vs 0.5, respectively, P = 0.02 for both). CV-related emergency room visitation (0.15 vs 0.08) rates were also numerically higher following an IAS, but did not reach statistical significance (P = 0.26). Patients experiencing an IAS accrued greater treatment costs during the 12 months postimplant compared to no-shock patients ($13,973 ± $46,345 vs $6,790 ± $19,091, P = 0.001). Recipients of IAS utilize the healthcare system more frequently following an IAS than patients not experiencing a shock. This increased utilization results in higher costs of treating IAS

  14. A Thematic Literature Review: The Importance of Providing Spiritual Care for End-of-Life Patients Who Have Experienced Transcendence Phenomena.

    Science.gov (United States)

    Broadhurst, Kathleen; Harrington, Ann

    2016-11-01

    The purpose of this review was to investigate within the literature the link between transcendent phenomena and peaceful death. The objectives were firstly to acknowledge the importance of such experiences and secondly to provide supportive spiritual care to dying patients. Information surrounding the aforementioned concepts is underreported in the literature. The following 4 key themes emerged: spiritual comfort; peaceful, calm death; spiritual transformation; and unfinished business The review established the importance of transcendence phenomena being accepted as spiritual experiences by health care professionals. Nevertheless, health care professionals were found to struggle with providing spiritual care to patients who have experienced them. Such phenomena are not uncommon and frequently result in peaceful death. Additionally, transcendence experiences of dying patients often provide comfort to the bereaved, assisting them in the grieving process. © The Author(s) 2015.

  15. Molecular dynamics simulation of shock wave and spallation phenomena in metal foils irradiated by femtosecond laser pulse

    Science.gov (United States)

    Zhakhovsky, Vasily; Demaske, Brian; Inogamov, Nail; Oleynik, Ivan

    2010-03-01

    Femtosecond laser irradiation of metals is an effective technique to create a high-pressure frontal layer of 100-200 nm thickness. The associated ablation and spallation phenomena can be studied in the laser pump-probe experiments. We present results of a large-scale MD simulation of ablation and spallation dynamics developing in 1,2,3μm thick Al and Au foils irradiated by a femtosecond laser pulse. Atomic-scale mechanisms of laser energy deposition, transition from pressure wave to shock, reflection of the shock from the rear-side of the foil, and the nucleation of cracks in the reflected tensile wave, having a very high strain rate, were all studied. To achieve a realistic description of the complex phenomena induced by strong compression and rarefaction waves, we developed new embedded atom potentials for Al and Au based on cold pressure curves. MD simulations revealed the complex interplay between spallation and ablation processes: dynamics of spallation depends on the pressure profile formed in the ablated zone at the early stage of laser energy absorption. It is shown that the essential information such as material properties at high strain rate and spall strength can be extracted from the simulated rear-side surface velocity as a function of time.

  16. Studies on shock phenomena in two-phase flow, (4). Characteristics in channel flow consisting of bubbly mixture and liquid in series

    Energy Technology Data Exchange (ETDEWEB)

    Akagawa, Koji; Fujii, Terushige; Ito, Yutaka; Hiraki, Sei

    1982-04-01

    The research carried out so far was related to the case in which the mean void ratio in a pipe distributed almost invariably in axial direction. However, in actual piping system, the distribution of void ratio sometimes changes in axial direction such as evaporating tubes. In this study, in order to clarify the basic characteristics of shock phenomena in a piping system in which the density of two-phase flow changes in axial direction, experiment was carried out on air and water two-component bubbly flow, in which single phase was in upstream, and two-phase flow with constant void ratio in axial direction was in downstream. Also, the theoretical study on the phenomena was performed. The experimental setup and experimental method, the result of the waveform of pressure response, the behavior of pressure waves at the interface of two-phase flow and single phase flow, the qualitative analysis of the waveform of pressure response, and the analysis of pressure rise are reported. By the sudden closure of a valve, the pressure in two-phase flow rose by the initial potential surge, thereafter stepped pressure rise was observed. This phenomenon can be explained by the reflection of pressure waves at the interface of two-phase flow and single phase flow.

  17. Paranormal phenomena

    Science.gov (United States)

    Gaina, Alex

    1996-08-01

    Critical analysis is given of some paranormal phenomena events (UFO, healers, psychokinesis (telekinesis))reported in Moldova. It is argued that correct analysis of paranormal phenomena should be made in the framework of electromagnetism.

  18. Experiencing control

    NARCIS (Netherlands)

    Monaci, G.; Braspenning, R.A.C.; Meerbeek, B.W.; Bingley, P.; Rajagopalan, R.; Triki, M.

    2009-01-01

    This report describes the activities carried out in the first part of the Experiencing Control project (2008-324). The guiding idea of the project is to make control part of the experience, exploring new interaction solutions for complex, engaging interactions with Philips devices in the living

  19. Study of Travelling Interplanetary Phenomena Report

    Science.gov (United States)

    Dryer, Murray

    1987-09-01

    Scientific progress on the topic of energy, mass, and momentum transport from the Sun into the heliosphere is contingent upon interdisciplinary and international cooperative efforts on the part of many workers. Summarized here is a report of some highlights of research carried out during the SMY/SMA by the STIP (Study of Travelling Interplanetary Phenomena) Project that included solar and interplanetary scientists around the world. These highlights are concerned with coronal mass ejections from solar flares or erupting prominences (sometimes together); their large-scale consequences in interplanetary space (such as shocks and magnetic 'bubbles'); and energetic particles and their relationship to these large-scale structures. It is concluded that future progress is contingent upon similar international programs assisted by real-time (or near-real-time) warnings of solar activity by cooperating agencies along the lines experienced during the SMY/SMA.

  20. Experiencing variation

    DEFF Research Database (Denmark)

    Kobayashi, Sofie; Berge, Maria; Grout, Brian William Wilson

    2017-01-01

    This study contributes towards a better understanding of learning dynamics in doctoral supervision by analysing how learning opportunities are created in the interaction between supervisors and PhD students, using the notion of experiencing variation as a key to learning. Empirically, we have based...... the study on four video-recorded sessions, with four different PhD students and their supervisors, all from life sciences. Our analysis revealed that learning opportunities in the supervision sessions concerned either the content matter of research (for instance, understanding soil structure......), or the research methods— more specifically how to produce valid results. Our results illustrate how supervisors and PhD students create a space of learning together in their particular discipline by varying critical aspects of their research in their discussions. Situations where more openended research issues...

  1. Experiencing time

    CERN Document Server

    Prosser, Simon

    2018-01-01

    Our engagement with time is a ubiquitous feature of our lives. We are aware of time on many scales, from the briefest flicker of change to the way our lives unfold over many years. But to what extent does this encounter reveal the true nature of temporal reality? To the extent that temporal reality is as it seems, how do we come to be aware of it? And to the extent that temporal reality is not as it seems, why does it seem that way? These are the central questions addressed by Simon Prosser in Experiencing Time. These questions take on a particular importance in philosophy for two reasons. Firstly, there is a view concerning the metaphysics of time, known as the B-theory of time, according to which the apparently dynamic quality of change, the special status of the present, and even the passage of time are all illusions. Instead, the world is a four-dimensional space-time block, lacking any of the apparent dynamic features of time. If the B-theory is correct, as the book argues, then it must be explained why ...

  2. Switching Phenomena

    Science.gov (United States)

    Stanley, H. E.; Buldyrev, S. V.; Franzese, G.; Havlin, S.; Mallamace, F.; Mazza, M. G.; Kumar, P.; Plerou, V.; Preis, T.; Stokely, K.; Xu, L.

    One challenge of biology, medicine, and economics is that the systems treated by these serious scientific disciplines can suddenly "switch" from one behavior to another, even though they possess no perfect metronome in time. As if by magic, out of nothing but randomness one finds remarkably fine-tuned processes in time. The past century has, philosophically, been concerned with placing aside the human tendency to see the universe as a fine-tuned machine. Here we will address the challenge of uncovering how, through randomness (albeit, as we shall see, strongly correlated randomness), one can arrive at some of the many temporal patterns in physics, economics, and medicine and even begin to characterize the switching phenomena that enable a system to pass from one state to another. We discuss some applications of correlated randomness to understanding switching phenomena in various fields. Specifically, we present evidence from experiments and from computer simulations supporting the hypothesis that water's anomalies are related to a switching point (which is not unlike the "tipping point" immortalized by Malcolm Gladwell), and that the bubbles in economic phenomena that occur on all scales are not "outliers" (another Gladwell immortalization).

  3. Transport phenomena

    International Nuclear Information System (INIS)

    Kirczenow, G.; Marro, J.

    1974-01-01

    Some simple remarks on the basis of transport theory. - Entropy, dynamics and scattering theory. - Response, relaxation and fluctuation. - Fluctuating hydrodynamics and renormalization of susceptibilities and transport coefficients. - Irreversibility of the transport equations. - Ergodic theory and statistical mechanics. - Correlation functions in Heisenberg magnets. - On the Enskog hard-sphere kinetic eqquation and the transport phenomena of dense simple gases. - What can one learn from Lorentz models. - Conductivity in a magnetic field. - Transport properties in gases in presence of external fields. - Transport properties of dilute gases with internal structure. (orig.) [de

  4. Electromagnetically driven radiative shocks and their measurements

    International Nuclear Information System (INIS)

    Kondo, K.; Watanabe, M.; Nakajima, M.; Kawamura, T.; Horioka, K.

    2005-01-01

    Experimental results on a generation of strong shocks in a compact pulse power device are reported. The characteristics of strong shocks are different from hydrodynamical shocks' because they depend on not only collisions but radiation processes. Radiative shocks are relevant to high energy density phenomena such as the explosions of supernovae. When initial pressure is lower than about 50 mtorr, an interesting structure is confirmed at the shock front, which might indicate a phenomenon proceeded by the radiative process. (author)

  5. Nonlinearity, Conservation Law and Shocks

    Indian Academy of Sciences (India)

    Almost all natural phenomena, and social and economic changes, .... reference moving with velocity c also by the same symbol x and ... abstract as can be seen from the publication of the book Shock Waves and Reaction Diffusion Equation.

  6. Cavitation phenomena in extracorporeal microexplosion lithotripsy

    Science.gov (United States)

    Tomita, Y.; Obara, T.; Takayama, K.; Kuwahara, M.

    1994-09-01

    An experimental investigation was made of cavitation phenomena induced by underwater shock wave focusing applied to the extracorporeal microexplosion lithotripsy (microexplosion ESWL). Firstly an underwater microexplosion generated by detonation of a 10 mg silver azide pellet was studied and secondly underwater shock focusing and its induced cavitation phenomena were investgated. Underwater shock wave was focused by using a semi-ellipsoidal reflector in which a shock wave generated at the first focal point of the reflector was reflected and focused at the second focal point. It is found that an explosion product gas bubble did not produce any distinct rebound shocks. Meantime cavitation appeared after shock focusing at the second focal point where expansion waves originated at the exit of the reflector were simultaneously collected. A shock/bubble interaction is found to contribute not only to urinary tract stone disintegration but also tissue damage. The cavitation effect associated with the microexplosion ESWL was weaker in comparison with a spark discharge ESWL. The microexplosion ESWL is an effective method which can minimize the number of shock exposures hence decreasing tissue damage by conducting precise positioning of urinary tract stones.

  7. Plasma phenomena around comets: interaction with the solar wind

    International Nuclear Information System (INIS)

    Sagdeev, R.Z.; Shapiro, V.D.; Shevchenko, V.I.; Szegoe, K.

    1987-08-01

    The most important plasma physical experimental data measured during the cometary missions are summarized. These data do not include tail phenomena. Theoretical considerations are also presented concerning the upstream and bow shock regions. (author) 47 refs.; 15 figs

  8. The LENS Facilities and Experimental Studies to Evaluate the Modeling of Boundary Layer Transition, Shock/Boundary Layer Interaction, Real Gas, Radiation and Plasma Phenomena in Contemporary CFD Codes

    Science.gov (United States)

    2010-04-01

    Layer Interaction, Real Gas, Radiation and Plasma Phenomena in Contemporary CFD Codes Michael S. Holden, PhD CUBRC , Inc. 4455 Genesee Street Buffalo...NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) CUBRC , Inc. 4455 Genesee Street Buffalo, NY 14225, USA 8. PERFORMING...HyFly Navy EMRG Reentry-F Slide 2 X-43 HIFiRE-2 Figure 17: Transition in Hypervelocity Flows: CUBRC Focus – Fully Duplicated Ground Test

  9. Dropout Phenomena at Universities

    DEFF Research Database (Denmark)

    Larsen, Michael Søgaard; Kornbeck, Kasper Pihl; Kristensen, Rune

    Dropout from university studies comprises a number of complex phenomena with serious complex consequences and profound political attention. Further analysis of the field is, therefore, warranted. Such an analysis is offered here as a systematic review which gives answers based on the best possible...... such dropout phenomena occur at universities? What can be done by the universities to prevent or reduce such dropout phenomena?...

  10. The earth's foreshock, bow shock, and magnetosheath

    Science.gov (United States)

    Onsager, T. G.; Thomsen, M. F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions.

  11. The earth's foreshock, bow shock, and magnetosheath

    International Nuclear Information System (INIS)

    Onsager, T.G.; Thomsen, M.F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions. 184 refs

  12. Understanding the physics of changing mass phenomena

    NARCIS (Netherlands)

    Ellermeijer, A.L.

    2008-01-01

    Changing mass phenomena, like a falling chain or a bungee jumper, might give surprising results, even for experienced physicists. They have resulted in hot discussions in journals, in which for instance Physics professors claim the impossibility of an acceleration larger then g in case of a bungee

  13. Experimental methods of shock wave research

    CERN Document Server

    Seiler, Friedrich

    2016-01-01

    This comprehensive and carefully edited volume presents a variety of experimental methods used in Shock Waves research. In 14 self contained chapters this 9th volume of the “Shock Wave Science and Technology Reference Library” presents the experimental methods used in Shock Tubes, Shock Tunnels and Expansion Tubes facilities. Also described is their set-up and operation. The uses of an arc heated wind tunnel and a gun tunnel are also contained in this volume. Whenever possible, in addition to the technical description some typical scientific results obtained using such facilities are described. Additionally, this authoritative book includes techniques for measuring physical properties of blast waves and laser generated shock waves. Information about active shock wave laboratories at different locations around the world that are not described in the chapters herein is given in the Appendix, making this book useful for every researcher involved in shock/blast wave phenomena.

  14. Fundamentals of Fire Phenomena

    DEFF Research Database (Denmark)

    Quintiere, James

    analyses. Fire phenomena encompass everything about the scientific principles behind fire behaviour. Combining the principles of chemistry, physics, heat and mass transfer, and fluid dynamics necessary to understand the fundamentals of fire phenomena, this book integrates the subject into a clear...

  15. Shock tube Multiphase Experiments

    Science.gov (United States)

    Middlebrooks, John; Allen, Roy; Paudel, Manoj; Young, Calvin; Musick, Ben; McFarland, Jacob

    2017-11-01

    Shock driven multiphase instabilities (SDMI) are unique physical phenomena that have far-reaching practical applications in engineering and science. The instability is present in high energy explosions, scramjet combustors, and supernovae events. The SDMI arises when a multiphase interface is impulsively accelerated by the passage of a shockwave. It is similar in development to the Richtmyer-Meshkov (RM) instability however, particle-to-gas coupling is the driving mechanism of the SDMI. As particle effects such as lag and phase change become more prominent, the SDMI's development begins to significantly deviate from the RM instability. We have developed an experiment for studying the SDMI in our shock tube facility. In our experiments, a multiphase interface is created using a laminar jet and flowed into the shock tube where it is accelerated by the passage of a planar shockwave. The interface development is captured using CCD cameras synchronized with planar laser illumination. This talk will give an overview of new experiments conducted to examine the development of a shocked cylindrical multiphase interface. The effects of Atwood number, particle size, and a second acceleration (reshock) of the interface will be discussed.

  16. Shock absorber

    International Nuclear Information System (INIS)

    Nemeth, J.D.

    1981-01-01

    A shock absorber for the support of piping and components in a nuclear power plant is described. It combines a high degree of stiffness under sudden shocks, e.g. seismic disturbances, with the ability to allow for thermal expansion without resistance when so required. (JIW)

  17. Bow shock data analysis

    Science.gov (United States)

    Zipf, Edward C.; Erdman, Peeter W.

    1994-08-01

    The University of Pittsburgh Space Physics Group in collaboration with the Army Research Office (ARO) modeling team has completed a systematic organization of the shock and plume spectral data and the electron temperature and density measurements obtained during the BowShock I and II rocket flights which have been submitted to the AEDC Data Center, has verified the presence of CO Cameron band emission during the Antares engine burn and for an extended period of time in the post-burn plume, and have adapted 3-D radiation entrapment codes developed by the University of Pittsburgh to study aurora and other atmospheric phenomena that involve significant spatial effects to investigate the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV) envelope surrounding the re-entry that create an extensive plasma cloud by photoionization.

  18. Undercuts by Laser Shock Forming

    International Nuclear Information System (INIS)

    Wielage, Hanna; Vollertsen, Frank

    2011-01-01

    In laser shock forming TEA-CO 2 -laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 μm were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

  19. Phenomena of charged particles transport in variable magnetic fields

    International Nuclear Information System (INIS)

    Savane, Sy Y.; Faza Barry, M.; Vladmir, L.; Diaby, I.

    2002-11-01

    This present work is dedicated to the study of the dynamical phenomena for the transport of ions in the presence of variable magnetic fields in front of the Jupiter wave shock. We obtain the spectrum of the accelerated ions and we study the conditions of acceleration by solving the transport equation in the planetocentric system. We discuss the theoretical results obtained and make a comparison with the experimental parameters in the region of acceleration behind the Jupiter wave shock. (author)

  20. Condensed matter at high shock pressures

    International Nuclear Information System (INIS)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-01-01

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N 2 , CO, SiO 2 -aerogel, H 2 O, and C 6 H 6 . The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab

  1. Ultrashort Laser Pulse Phenomena

    CERN Document Server

    Diels, Jean-Claude

    2006-01-01

    Ultrashort Laser Pulse Phenomena, 2e serves as an introduction to the phenomena of ultra short laser pulses and describes how this technology can be used to examine problems in areas such as electromagnetism, optics, and quantum mechanics. Ultrashort Laser Pulse Phenomena combines theoretical backgrounds and experimental techniques and will serve as a manual on designing and constructing femtosecond (""faster than electronics"") systems or experiments from scratch. Beyond the simple optical system, the various sources of ultrashort pulses are presented, again with emphasis on the basic

  2. Science and Paranormal Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, H. Pierre

    1999-06-03

    In order to ground my approach to the study of paranormal phenomena, I first explain my operational approach to physics, and to the ''historical'' sciences of cosmic, biological, human, social and political evolution. I then indicate why I believe that ''paranormal phenomena'' might-but need not- fit into this framework. I endorse the need for a new theoretical framework for the investigation of this field presented by Etter and Shoup at this meeting. I close with a short discussion of Ted Bastin's contention that paranormal phenomena should be defined as contradicting physics.

  3. Nonequilibrium Phenomena in Plasmas

    CERN Document Server

    Sharma, A Surjalal

    2005-01-01

    The complexity of plasmas arises mainly from their inherent nonlinearity and far from equilibrium nature. The nonequilibrium behavior of plasmas is evident in the natural settings, for example, in the Earth's magnetosphere. Similarly, laboratory plasmas such as fusion bottles also have their fair share of complex behavior. Nonequilibrium phenomena are intimately connected with statistical dynamics and form one of the growing research areas in modern nonlinear physics. These studies encompass the ideas of self-organization, phase transition, critical phenomena, self-organized criticality and turbulence. This book presents studies of complexity in the context of nonequilibrium phenomena using theory, modeling, simulations, and experiments, both in the laboratory and in nature.

  4. Nonlinear surface electromagnetic phenomena

    CERN Document Server

    Ponath, H-E

    1991-01-01

    In recent years the physics of electromagnetic surface phenomena has developed rapidly, evolving into technologies for communications and industry, such as fiber and integrated optics. The variety of phenomena based on electromagnetism at surfaces is rich and this book was written with the aim of summarizing the available knowledge in selected areas of the field. The book contains reviews written by solid state and optical physicists on the nonlinear interaction of electromagnetic waves at and with surfaces and films. Both the physical phenomena and some potential applications are

  5. demystifying the shock of shocking

    African Journals Online (AJOL)

    (with a pulse), atrial fibrillation and atrial flutter. The energy dose in cardioversion is less (0.5. - 2 J/kg) than in defibrillation (2 - 4 J/kg). In cardioversion the shock is discharged synchronously with the native R wave of the patient. Without synchronisation,. VF can be induced if a shock is delivered during the refractory period ...

  6. INTERFERENCE OF COUNTERPROPAGATING SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-03-01

    Full Text Available The subject of study. We examined the interaction of counterpropagating shock waves. The necessity of counterpropagating shock waves studying occurs at designing of high Mach number modern internal compression air intakes, Ramjets with subsonic and supersonic combustion, in asymmetrical supersonic nozzles and in some other cases. In a sense, this problem is a generalization of the case of an oblique shock reflection from the wall or from the plane of symmetry. With the renewed vigor, the interest to this problem emerged at the end of the 90s. This was due to the start of the programs for flight study at hypersonic speeds. The first experiments performed with air intakes, which realized the interaction of counterpropagating shock waves have shown that the change in flow velocity is accompanied by abrupt alteration of shock-wave structure, the occurrence of nonstationary and oscillatory phenomena. With an increase of flow velocity these phenomena undesirable for aircraft structure became more marked. The reason is that there are two fundamentally different modes of interaction of counterpropagating shock waves: a four-wave regular and a five-wave irregular. The transition from one mode to another can be nonstationary abrupt or gradual, it can also be accompanied by hysteresis. Main results. Criteria for the transition from regular reflection of counterpropagating shock waves to irregular are described: the criterion of von Neumann and the stationary Mach configuration criterion. We described areas in which the transition from one reflection type to another is possible only in abrupt way, as well as areas of possible gradual transition. Intensity dependences of the reflected shock waves from the intensity of interacting counterpropagating shocks were given. Qualitative pictures of shock-wave structures arising from the interaction of counterpropagating shock waves were shown. Calculation results of the intensity of outgoing gas

  7. Interfacial transport phenomena

    CERN Document Server

    Slattery, John C; Oh, Eun-Suok

    2007-01-01

    Revised and updated extensively from the previous editionDiscusses transport phenomena at common lines or three-phase lines of contactProvides a comprehensive summary about the extensions of continuum mechanics to the nanoscale.

  8. Severe accident phenomena

    International Nuclear Information System (INIS)

    Jokiniemi, J.; Kilpi, K.; Lindholm, I.; Maekynen, J.; Pekkarinen, E.; Sairanen, R.; Silde, A.

    1995-02-01

    Severe accidents are nuclear reactor accidents in which the reactor core is substantially damaged. The report describes severe reactor accident phenomena and their significance for the safety of nuclear power plants. A comprehensive set of phenomena ranging from accident initiation to containment behaviour and containment integrity questions are covered. The report is based on expertise gained in the severe accident assessment projects conducted at the Technical Research Centre of Finland (VTT). (49 refs., 32 figs., 12 tabs.)

  9. Introduction to wetting phenomena

    International Nuclear Information System (INIS)

    Indekeu, J.O.

    1995-01-01

    In these lectures the field of wetting phenomena is introduced from the point of view of statistical physics. The phase transition from partial to complete wetting is discussed and examples of relevant experiments in binary liquid mixtures are given. Cahn's concept of critical-point wetting is examined in detail. Finally, a connection is drawn between wetting near bulk criticality and the universality classes of surface critical phenomena. (author)

  10. Hypovolemic shock

    Science.gov (United States)

    ... the person's position unless they are in immediate danger. Do not give fluids by mouth. If person ... the patient with shock. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  11. Shock absorber

    International Nuclear Information System (INIS)

    Housman, J.J.

    1978-01-01

    A shock absorber is described for use in a hostile environment at the end of a blind passage for absorbing impact loads. The shock absorber includes at least one element which occupies the passage and which is comprised of a porous brittle material which is substantially non-degradable in the hostile environment. A void volume is provided in the element to enable the element to absorb a predetermined level of energy upon being crushed due to impact loading

  12. A shock absorber model for structure-borne noise analyses

    Science.gov (United States)

    Benaziz, Marouane; Nacivet, Samuel; Thouverez, Fabrice

    2015-08-01

    Shock absorbers are often responsible for undesirable structure-borne noise in cars. The early numerical prediction of this noise in the automobile development process can save time and money and yet remains a challenge for industry. In this paper, a new approach to predicting shock absorber structure-borne noise is proposed; it consists in modelling the shock absorber and including the main nonlinear phenomena responsible for discontinuities in the response. The model set forth herein features: compressible fluid behaviour, nonlinear flow rate-pressure relations, valve mechanical equations and rubber mounts. The piston, base valve and complete shock absorber model are compared with experimental results. Sensitivity of the shock absorber response is evaluated and the most important parameters are classified. The response envelope is also computed. This shock absorber model is able to accurately reproduce local nonlinear phenomena and improves our state of knowledge on potential noise sources within the shock absorber.

  13. Shock parameter calculations at weak interplanetary shock waves

    Directory of Open Access Journals (Sweden)

    J. M. Gloag

    2005-02-01

    Full Text Available A large set of interplanetary shock waves observed using the Ulysses spacecraft is analysed in order to determine their local parameters. For the first time a detailed analysis is extended to the thermodynamic properties of a large number of events. The intention is to relate the shock parameters to the requirements set by MHD shock theory. A uniform approach is adopted in the selection of up and downstream regions for this analysis and applied to all the shock waves. Initially, the general case of a 3 component adiabatic plasma is considered. However, the calculation of magnetosonic and Alfvénic Mach numbers and the ratio of downstream to upstream entropy produce some unexpected results. In some cases there is no clear increase in entropy across the shock and also the magnetosonic Mach number can be less than 1. It is found that a more discerning use of data along with an empirical value for the polytropic index can raise the distribution of downstream to upstream entropy ratios to a more acceptable level. However, it is also realised that many of these shocks are at the very weakest end of the spectrum and associated phenomena may also contribute to the explanation of these results.

  14. Ion exchange phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  15. Are you experienced?

    DEFF Research Database (Denmark)

    Dahl, Michael Slavensky; Reichstein, Toke

    This paper investigates the relationship between the level of experience of managers and founders, and the likelihood of survival of their new firms. We take advantage of a comprehensive dataset covering the entire Danish labor market from 1980-2000. This is used to trace the activities of top...... ranked members of start-ups prior to their founding, and follow the fate of these firms. More specifically, we compare the survival of spin-offs from surviving parents, spin-offs from exiting parents, and other start-ups. Moreover, we investigate whether firms managed and founded by more experienced....... We also find that spin-offs from parent companies that exit are less likely to survive than either spin-offs from surviving parents or other start-ups. These findings support the theoretical arguments that organizational heritage is important for the survival of new organizations. We found no similar...

  16. SEPARATION PHENOMENA LOGISTIC REGRESSION

    Directory of Open Access Journals (Sweden)

    Ikaro Daniel de Carvalho Barreto

    2014-03-01

    Full Text Available This paper proposes an application of concepts about the maximum likelihood estimation of the binomial logistic regression model to the separation phenomena. It generates bias in the estimation and provides different interpretations of the estimates on the different statistical tests (Wald, Likelihood Ratio and Score and provides different estimates on the different iterative methods (Newton-Raphson and Fisher Score. It also presents an example that demonstrates the direct implications for the validation of the model and validation of variables, the implications for estimates of odds ratios and confidence intervals, generated from the Wald statistics. Furthermore, we present, briefly, the Firth correction to circumvent the phenomena of separation.

  17. Rheological phenomena in focus

    CERN Document Server

    Boger, DV

    1993-01-01

    More than possibly any other scientific discipline, rheology is easily visualized and the relevant literature contains many excellent photographs of unusual and often bizarre phenomena. The present book brings together these photographs for the first time. They are supported by a full explanatory text. Rheological Phenomena in Focus will be an indispensable support manual to all those who teach rheology or have to convince colleagues of the practical relevance of the subject within an industrial setting. For those who teach fluid mechanics, the book clearly illustrates the difference be

  18. Bioelectrochemistry II membrane phenomena

    CERN Document Server

    Blank, M

    1987-01-01

    This book contains the lectures of the second course devoted to bioelectro­ chemistry, held within the framework of the International School of Biophysics. In this course another very large field of bioelectrochemistry, i. e. the field of Membrane Phenomena, was considered, which itself consists of several different, but yet related subfields. Here again, it can be easily stated that it is impossible to give a complete and detailed picture of all membrane phenomena of biological interest in a short course of about one and half week. Therefore the same philosophy, as the one of the first course, was followed, to select a series of lectures at postgraduate level, giving a synthesis of several membrane phenomena chosen among the most'important ones. These lectures should show the large variety of membrane-regulated events occurring in living bodies, and serve as sound interdisciplinary basis to start a special­ ized study of biological phenomena, for which the investigation using the dual approach, physico-che...

  19. Sawtooth phenomena in tokamaks

    International Nuclear Information System (INIS)

    Kuvshinov, B.N.; Savrukhin, P.V.

    1989-01-01

    A review of experimental and theoretical investigaions of sawtooth phenomena in tokamaks is presented. Different types of sawtooth oscillations, scaling laws and methods of interanl disruption stabilization are described. Theoretical models of the sawtooth instability are discussed. 122 refs.; 4 tabs

  20. Fundamentals of wave phenomena

    CERN Document Server

    Hirose, Akira

    2010-01-01

    This textbook provides a unified treatment of waves that either occur naturally or can be excited and propagated in various media. This includes both longitudinal and transverse waves. The book covers both mechanical and electrical waves, which are normally covered separately due to their differences in physical phenomena.

  1. Investigation of Surface Phenomena in Shocked Tin in Converging Geometry

    Energy Technology Data Exchange (ETDEWEB)

    Rousculp, Christopher L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oro, David Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Griego, Jeffrey Randall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Turchi, Peter John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reinovsky, Robert Emil [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bradley, Joseph Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cheng, Baolian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Freeman, Matthew Stouten [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Patten, Austin Randall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-14

    There is a great interest in RMI as source of ejecta from metal shells. Previous experiments have explored wavelength amplitude (kA) variation but they have a small range of drive pressures and are in planer geometry. Simulations, both MD and hydro, have explored RMI in planer geometry. The ejecta source model from RMI is an area of active algorithm and code development in ASCI-IC Lagrangian Applications Project. PHELIX offers precise, reproducible variable driver for Hydro and material physics diagnoses with proton radiography.

  2. High-speed imaging of dynamic shock wave reflection phenomena

    CSIR Research Space (South Africa)

    Naidoo, K

    2010-09-01

    Full Text Available spring system with approximately 1000N. The tunnel and rig are operated remotely by a test team. At tunnel startup the wedges and spring system are locked with a custom designed latch system. The latch is released with an electric motor and this enables... remote operation. After the flow stabilizes at tunnel startup, the spring system is released and the wedges execute a pitch range of approximately 20 to 30 degrees in about 6 ms. The resultant motion is also influenced by the aerodynamic forces...

  3. Toxic shock syndrome

    Science.gov (United States)

    Staphylococcal toxic shock syndrome; Toxic shock-like syndrome; TSLS ... Toxic shock syndrome is caused by a toxin produced by some types of staphylococcus bacteria. A similar problem, called toxic shock- ...

  4. Introduction to Shock Waves and Shock Wave Research

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, William Wyatt [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-02

    M-9 and a number of other organizations at LANL and elsewhere study materials in dynamic processes. Often, this is described as “shock wave research,” but in reality is broader than is implied by that term. Most of our work is focused on dynamic compression and associated phenomena, but you will find a wide variety of things we do that, while related, are not simple compression of materials, but involve a much richer variety of phenomena. This tutorial will introduce some of the underlying physics involved in this work, some of the more common types of phenomena we study, and common techniques. However, the list will not be exhaustive by any means.

  5. Chaotic phenomena in plasmas

    International Nuclear Information System (INIS)

    Kawai, Y.

    1991-08-01

    It has recently been recognized that the research on various aspects of chaotic dynamics grows rapidly as one of some areas in nonlinear science. On the other hands, the plasma has long been called a treasure-house of nonlinear phenomena, so it is easy to imagine that the plasma is abundant in chaotic phenomena. In fact, the research on plasma chaos is going on, such as the research on the stochastic magnetic field and the chaotic orbit in the toroidal helical system, as well as the research in other experiments. To review the present status of the research on plasma chaos and to make clear the basic common physics, a working group was organized in 1990 as a collaboration research of National Institute for Fusion Science. This is the report on its activity in 1990, with a stress on experimental data obtained in basic plasma experiments and RFP, and on the relaxed theories and computer simulations. (author)

  6. Theory of threshold phenomena

    International Nuclear Information System (INIS)

    Hategan, Cornel

    2002-01-01

    Theory of Threshold Phenomena in Quantum Scattering is developed in terms of Reduced Scattering Matrix. Relationships of different types of threshold anomalies both to nuclear reaction mechanisms and to nuclear reaction models are established. Magnitude of threshold effect is related to spectroscopic factor of zero-energy neutron state. The Theory of Threshold Phenomena, based on Reduced Scattering Matrix, does establish relationships between different types of threshold effects and nuclear reaction mechanisms: the cusp and non-resonant potential scattering, s-wave threshold anomaly and compound nucleus resonant scattering, p-wave anomaly and quasi-resonant scattering. A threshold anomaly related to resonant or quasi resonant scattering is enhanced provided the neutron threshold state has large spectroscopic amplitude. The Theory contains, as limit cases, Cusp Theories and also results of different nuclear reactions models as Charge Exchange, Weak Coupling, Bohr and Hauser-Feshbach models. (author)

  7. Wolf-Rayet phenomena

    International Nuclear Information System (INIS)

    Conti, P.S.

    1982-01-01

    The author reviews in broad terms the concept of Wolf-Rayet (W-R) phenomena, outlines what we currently know about the properties of stars showing such phenomena and indicates the directions in which future work is leading. He begins by listing the characteristics of W-R spectra and then considers the following specific problems: the absolute visual magnitudes; the heterogeneity of WN spectra; the existence of transition type spectra and compositions; the mass loss rates; the existence of very luminous and possibly very massive W-R stars. He discusses briefly our current understanding of the theoretical aspects of stellar evolution and stellar winds and the various scenarios that have been proposed to understand W-R stars. (Auth.)

  8. Transport phenomena II essentials

    CERN Document Server

    REA, The Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Transport Phenomena II covers forced convention, temperature distribution, free convection, diffusitivity and the mechanism of mass transfer, convective mass transfer, concentration

  9. Modelling of transport phenomena

    International Nuclear Information System (INIS)

    Itoh, Kimitaka; Itoh, Sanae; Fukuyama, Atsushi.

    1993-09-01

    In this review article, we discuss key features of the transport phenomena and theoretical modelling to understand them. Experimental observations have revealed the nature of anomalous transport, i.e., the enhancement of the transport coefficients by the gradients of the plasma profiles, the pinch phenomena, the radial profile of the anomalous transport coefficients, the variation of the transport among the Bohm diffusion, Pseudo-classical confinement, L-mode and variety of improved confinement modes, and the sudden jumps such as L-H transition. Starting from the formalism of the transport matrix, the modelling based on the low frequency instabilities are reviewed. Theoretical results in the range of drift wave frequency are examined. Problems in theories based on the quasilinear and mixing-length estimates lead to the renewal of the turbulence theory, and the physics picture of the self-sustained turbulence is discussed. The theory of transport using the fluid equation of plasma is developed, showing that the new approach is very promising in explaining abovementioned characteristics of anomalous transport in both L-mode and improved confinement plasmas. The interference of the fluxes is the key to construct the physics basis of the bifurcation theory for the L-H transition. The present status of theories on the mechanisms of improved confinement is discussed. Modelling on the nonlocal nature of transport is briefly discussed. Finally, the impact of the anomalous transport on disruptive phenomena is also described. (author) 95 refs

  10. Large momentum transfer phenomena

    International Nuclear Information System (INIS)

    Imachi, Masahiro; Otsuki, Shoichiro; Matsuoka, Takeo; Sawada, Shoji.

    1978-01-01

    The large momentum transfer phenomena in hadron reaction drastically differ from small momentum transfer phenomena, and are described in this paper. Brief review on the features of the large transverse momentum transfer reactions is described in relation with two-body reactions, single particle productions, particle ratios, two jet structure, two particle correlations, jet production cross section, and the component of momentum perpendicular to the plane defined by the incident protons and the triggered pions and transverse momentum relative to jet axis. In case of two-body process, the exponent N of the power law of the differential cross section is a value between 10 to 11.5 in the large momentum transfer region. The breaks of the exponential behaviors into the power ones are observed at the large momentum transfer region. The break would enable to estimate the order of a critical length. The large momentum transfer phenomena strongly suggest an important role of constituents of hadrons in the hard region. Hard rearrangement of constituents from different initial hadrons induces large momentum transfer reactions. Several rules to count constituents in the hard region have been proposed so far to explain the power behavior. Scale invariant quark interaction and hard reactions are explained, and a summary of the possible types of hard subprocess is presented. (Kato, T.)

  11. 28th International Symposium on Shock Waves

    CERN Document Server

    2012-01-01

    The University of Manchester hosted the 28th International Symposium on Shock Waves between 17 and 22 July 2011. The International Symposium on Shock Waves first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW28 focused on the following areas: Blast Waves, Chemically Reacting Flows, Dense Gases and Rarefied Flows, Detonation and Combustion, Diagnostics, Facilities, Flow Visualisation, Hypersonic Flow, Ignition, Impact and Compaction, Multiphase Flow, Nozzle Flow, Numerical Methods, Propulsion, Richtmyer-Meshkov, Shockwave Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shockwave Phenomena and Applications, as well as Medical and Biological Applications. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 28 and individuals interested in these fields.

  12. Condensation phenomena in a turbine blade passage

    International Nuclear Information System (INIS)

    Skillings, S.A.

    1989-02-01

    The mechanisms associated with the formation and growth of water droplets in the large low-pressure (LP) turbines used for electrical power generation are poorly understood and recent measurements have indicated that an unusually high loss is associated with the initial nucleation of these droplets. In order to gain an insight into the phenomena which arise in the turbine situation, some experiments were performed to investigate the behaviour of condensing steam flows in a blade passage. This study has revealed the fundamental significance of droplet nucleation in modifying the single-phase flow structure and results are presented which show the change in shock wave pattern when inlet superheat and outlet Mach number are varied. The trailing-edge shock wave structure appears considerably more robust towards variation of inlet superheat than purely one-dimensional considerations may suggest and the inadequacies of adopting a one-dimensional theory to analyse multi-dimensional condensing flows are demonstrated. Over a certain range of outlet Mach numbers an oscillating shock wave will establish in the throat region of the blade passage and this has been shown to interact strongly with droplet nucleation, resulting in a considerably increased mean droplet size. The possible implications of these results for turbine performance are also discussed. (author)

  13. Shock waves and shock tubes; Proceedings of the Fifteenth International Symposium, Berkeley, CA, July 28-August 2, 1985

    International Nuclear Information System (INIS)

    Bershader, D.; Hanson, R.

    1986-01-01

    A detailed survey is presented of shock tube experiments, theoretical developments, and applications being carried out worldwide. The discussions explore shock tube physics and the related chemical, physical and biological science and technology. Extensive attention is devoted to shock wave phenomena in dusty gases and other multiphase and heterogeneous systems, including chemically reactive mixtures. Consideration is given to techniques for measuring, visualizing and theoretically modeling flowfield, shock wave and rarefaction wave characteristics. Numerical modeling is explored in terms of the application of computational fluid dynamics techniques to describing flowfields in shock tubes. Shock interactions and propagation, in both solids, fluids, gases and mixed media are investigated, along with the behavior of shocks in condensed matter. Finally, chemical reactions that are initiated as the result of passage of a shock wave are discussed, together with methods of controlling the evolution of laminar separated flows at concave corners on advanced reentry vehicles

  14. Transient shocks beyond the heliopause

    International Nuclear Information System (INIS)

    Fermo, R L; Pogorelov, N V; Burlaga, L F

    2015-01-01

    The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression/rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. We present numerical simulations of such shocks in the year of 2000, when both Voyager spacecraft were in the supersonic solar wind region, and in 2012, when Voyager 1 observed traveling shocks. In the former case, Voyager observations themselves provide time- dependent boundary conditions in the solar wind. In the latter case, we use OMNI data at 1 AU to analyze the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Numerical results are compared with spacecraft observations. (paper)

  15. A study of water hammer phenomena in a one-component two-phase bubbly flow

    International Nuclear Information System (INIS)

    Fujii, Terushige; Akagawa, Koji

    2000-01-01

    Water hammer phenomena caused by a rapid valve closure, that is, shock phenomena in two-phase flows, are an important problem for the safety assessment of a hypothetical LOCA. This paper presents the results of experimental and analytical studies of the water hammer phenomena in a one-component tow-phase bubbly flow. In order to clarify the characteristics of water hammer phenomena, experiments for a one-component two-phase flow of Freon R-113 were conducted and a numerical simulation of pressure transients was developed. An overall picture of the water hammer phenomena in a one-component two-phase flow is presented an discussed. (author)

  16. Quantification of natural phenomena

    International Nuclear Information System (INIS)

    Botero Alvarez, Javier

    1997-01-01

    The science is like a great spider's web in which unexpected connections appear and therefore it is frequently difficult to already know the consequences of new theories on those existent. The physics is a clear example of this. The Newton mechanics laws describe the physical phenomena observable accurately by means of our organs of the senses or by means of observation teams not very sophisticated. After their formulation at the beginning of the XVIII Century, these laws were recognized in the scientific world as a mathematical model of the nature. Together with the electrodynamics law, developed in the XIX century, and the thermodynamic one constitutes what we call the classic physics. The state of maturity of the classic physics at the end of last century it was such that some scientists believed that the physics was arriving to its end obtaining a complete description of the physical phenomena. The spider's web of the knowledge was supposed finished, or at least very near its termination. It ended up saying, in arrogant form, that if the initial conditions of the universe were known, we could determine the state of the same one in any future moment. Two phenomena related with the light would prove in firm form that mistaken that they were, creating unexpected connections in the great spider's web of the knowledge and knocking down part of her. The thermal radiation of the bodies and the fact that the light spreads to constant speed in the hole, without having an absolute system of reference with regard to which this speed is measured, they constituted the decisive factors in the construction of a new physics. The development of sophisticated of measure teams gave access to more precise information and it opened the microscopic world to the observation and confirmation of existent theories

  17. Shock Waves

    CERN Document Server

    Jiang, Z

    2005-01-01

    The International Symposium on Shock Waves (ISSW) is a well established series of conferences held every two years in a different location. A unique feature of the ISSW is the emphasis on bridging the gap between physicists and engineers working in fields as different as gas dynamics, fluid mechanics and materials sciences. The main results presented at these meetings constitute valuable proceedings that offer anyone working in this field an authoritative and comprehensive source of reference.

  18. Acoustic phenomena during boiling

    International Nuclear Information System (INIS)

    Dorofeev, B.M.

    1985-01-01

    Applied and theoretical significance of investigation into acoustic phenomena on boiling is discussed. Effect of spatial and time conditions on pressure vapour bubble has been elucidated. Collective effects were considered: acoustic interaction of bubbles, noise formation ion developed boiling, resonance and hydrodynamic autooscillations. Different methods for predicting heat transfer crisis using changes of accompanying noise characteristics were analysed. Principle peculiarities of generation mechanism of thermoacoustic autooscillations were analysed as well: formation of standing waves; change of two-phase medium contraction in a channel; relation of alternating pressure with boiling process as well as with instantaneous and local temperatures of heat transfer surface and liquid in a boundary layer

  19. Magnetohydrodynamic flow phenomena

    International Nuclear Information System (INIS)

    Gerbeth, G.; Mutschke, G.; Eckert, S.

    1995-01-01

    The MHD group of the Institute of Safety Research performs basic studies on fluid dynamics and heat/mass transfer in fluids, particularly for electrically conducting fluids (liquid metals) exposed to external magnetic fields (Magnetohydrodynamics - MHD). Such a contactless influence on transport phenomena is of principal importance for a variety of applied problems including safety and design aspects in liquid metal cooled fusion reactors, fast reactors, and chemical systems. Any electrically conducting flow can be influenced without any contact by means of an external electromagnetic field. This, of course, can change the known hydromechanically flow patterns considerably. In the following two examples of such magnetic field influence are presented. (orig.)

  20. Random phenomena; Phenomenes aleatoires

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, G. [Commissariat a l' energie atomique et aux energies alternatives - CEA, C.E.N.G., Service d' Electronique, Section d' Electronique, Grenoble (France)

    1963-07-01

    This document gathers a set of conferences presented in 1962. A first one proposes a mathematical introduction to the analysis of random phenomena. The second one presents an axiomatic of probability calculation. The third one proposes an overview of one-dimensional random variables. The fourth one addresses random pairs, and presents basic theorems regarding the algebra of mathematical expectations. The fifth conference discusses some probability laws: binomial distribution, the Poisson distribution, and the Laplace-Gauss distribution. The last one deals with the issues of stochastic convergence and asymptotic distributions.

  1. Transport phenomena I essentials

    CERN Document Server

    REA, The Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Transport Phenomena I includes viscosity, flow of Newtonian fluids, velocity distribution in laminar flow, velocity distributions with more than one independent variable, thermal con

  2. Phase Plane Analysis Method of Nonlinear Traffic Phenomena

    Directory of Open Access Journals (Sweden)

    Wenhuan Ai

    2015-01-01

    Full Text Available A new phase plane analysis method for analyzing the complex nonlinear traffic phenomena is presented in this paper. This method makes use of variable substitution to transform a traditional traffic flow model into a new model which is suitable for the analysis in phase plane. According to the new model, various traffic phenomena, such as the well-known shock waves, rarefaction waves, and stop-and-go waves, are analyzed in the phase plane. From the phase plane diagrams, we can see the relationship between traffic jams and system instability. So the problem of traffic flow could be converted into that of system stability. The results show that the traffic phenomena described by the new method is consistent with that described by traditional methods. Moreover, the phase plane analysis highlights the unstable traffic phenomena we are chiefly concerned about and describes the variation of density or velocity with time or sections more clearly.

  3. Maximum intensity of rarefaction shock waves for dense gases

    NARCIS (Netherlands)

    Guardone, A.; Zamfirescu, C.; Colonna, P.

    2009-01-01

    Modern thermodynamic models indicate that fluids consisting of complex molecules may display non-classical gasdynamic phenomena such as rarefaction shock waves (RSWs) in the vapour phase. Since the thermodynamic region in which non-classical phenomena are physically admissible is finite in terms of

  4. Direct channel problems and phenomena

    International Nuclear Information System (INIS)

    Cutkosky, R.E.

    1975-01-01

    Direct channel problems and phenomena are considered covering the need for precision hadron spectroscopy, the data base for precision hadron spectroscopy, some relations between direct-channel and cross-channel effects, and spin rotation phenomena

  5. Phenomena Associated With EIT Waves

    Science.gov (United States)

    Thompson, B. J.; Biesecker, D. A.; Gopalswamy, N.

    2003-01-01

    We discuss phenomena associated with "EIT Wave" transients. These phenomena include coronal mass ejections, flares, EUV/SXR dimmings, chromospheric waves, Moreton waves, solar energetic particle events, energetic electron events, and radio signatures. Although the occurrence of many phenomena correlate with the appearance of EIT waves, it is difficult to mfer which associations are causal. The presentation will include a discussion of correlation surveys of these phenomena.

  6. Advanced and Exploratory Shock Sensing Mechanisms.

    Energy Technology Data Exchange (ETDEWEB)

    Nelsen, Nicholas H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kolb, James D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kulkarni, Akshay G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorscher, Zachary [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Habing, Clayton D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mathis, Allen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Beller, Zachary J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Mechanical component response to shock environments must be predictable in order to ensure reliability and safety. Whether the shock input results from accidental drops during transportation to projectile impact scenarios, the system must irreversibly transition into a safe state that is incapable of triggering the component . With this critical need in mind, the 2017 Nuclear Weapons Summer Product Realization Institute (NW SPRINT) program objective sought the design of a passive shock failsafe with emphasis on additively manufactured (AM) components. Team Advanced and Exploratory (A&E) responded to the challenge by designing and delivering multiple passive shock sensing mech anisms that activate within a prescribed mechanical shock threshold. These AM failsafe designs were tuned and validated using analytical and computational techniques including the shock response spectrum (SRS) and finite element analysis (FEA). After rapid prototyping, the devices experienced physical shock tests conducted on Sandia drop tables to experimentally verify performance. Keywords: Additive manufacturing, dynamic system, failsafe, finite element analysis, mechanical shock, NW SPRINT, shock respon se spectrum

  7. Vacuum arc anode phenomena

    International Nuclear Information System (INIS)

    Miller, H.C.

    1976-01-01

    A brief review of anode phenomena in vacuum arcs is presented. Discussed in succession are: the transition of the arc into the anode spot mode; the temperature of the anode before, during and after the anode spot forms; and anode ions. Characteristically the anode spot has a temperature of the order of the atmospheric boiling point of the anode material and is a copious source of vapor and energetic ions. The dominant mechanism controlling the transition of the vacuum arc into the anode spot mode appears to depend upon the electrode geometry, the electrode material, and the current waveform of the particular vacuum arc being considered. Either magnetic constriction in the gap plasma or gross anode melting can trigger the transition; indeed, a combination of the two is a common cause of anode spot formation

  8. Foot morphometric phenomena.

    Science.gov (United States)

    Agić, Ante

    2007-06-01

    Knowledge of the foot morphometry is important for proper foot structure and function. Foot structure as a vital part of human body is important for many reasons. The foot anthropometric and morphology phenomena are analyzed together with hidden biomechanical descriptors in order to fully characterize foot functionality. For Croatian student population the scatter data of the individual foot variables were interpolated by multivariate statistics. Foot morphometric descriptors are influenced by many factors, such as life style, climate, and things of great importance in human society. Dominant descriptors related to fit and comfort are determined by the use 3D foot shape and advanced foot biomechanics. Some practical recommendations and conclusions for medical, sportswear and footwear practice are highlighted.

  9. Workshop on Interface Phenomena

    CERN Document Server

    Kreuzer, Hans

    1987-01-01

    This book contains the proceedings of the first Workshop on Interface Phenomena, organized jointly by the surface science groups at Dalhousie University and the University of Maine. It was our intention to concentrate on just three topics related to the kinetics of interface reactions which, in our opinion, were frequently obscured unnecessarily in the literature and whose fundamental nature warranted an extensive discussion to help clarify the issues, very much in the spirit of the Discussions of the Faraday Society. Each session (day) saw two principal speakers expounding the different views; the session chairmen were asked to summarize the ensuing discussions. To understand the complexity of interface reactions, paradigms must be formulated to provide a framework for the interpretation of experimen­ tal data and for the construction of theoretical models. Phenomenological approaches have been based on a small number of rate equations for the concentrations or mole numbers of the various species involved i...

  10. Fast fission phenomena

    International Nuclear Information System (INIS)

    Gregoire, Christian.

    1982-03-01

    Experimental studies of fast fission phenomena are presented. The paper is divided into three parts. In the first part, problems associated with fast fission processes are examined in terms of interaction potentials and a dynamic model is presented in which highly elastic collisions, the formation of compound nuclei and fast fission appear naturally. In the second part, a description is given of the experimental methods employed, the observations made and the preliminary interpretation of measurements suggesting the occurence of fast fission processes. In the third part, our dynamic model is incorporated in a general theory of the dissipative processes studied. This theory enables fluctuations associated with collective variables to be calculated. It is applied to highly inelastic collisions, to fast fission and to the fission dynamics of compound nuclei (for which a schematic representation is given). It is with these calculations that the main results of the second part can be interpreted [fr

  11. Some perspectives in nuclear astrophysics on non-thermal phenomena

    International Nuclear Information System (INIS)

    Tatischeff, V.

    2012-01-01

    In this HDR (Accreditation to Supervise Researches) report, the author presents and comments his research activities on nuclear phenomena in stellar eruptions (solar eruptions, lithium nucleosynthesis in stellar eruptions), on particle acceleration in shock waves of stellar explosions (diffusive acceleration by shock wave, particle acceleration in symbiotic novae, particle acceleration in radio-detected supernovae), of research on low energy cosmic rays (galactic emission of nuclear gamma rays, non thermal soft X rays as new tracer of accelerated particles), and on the origin of short period radioactivities in the primitive solar system (extinguished radio-activities and formation of the solar system, origin of berylium-10 in the primitive solar system). The author concludes with some perspectives on non thermal phenomena in nuclear astrophysics, and on research and development for the future of medium-energy gamma astronomy [fr

  12. Shock Prevention

    Science.gov (United States)

    1978-01-01

    The electrician pictured is installing a General Electric Ground Fault Interrupter (GFI), a device which provides protection against electrical shock in the home or in industrial facilities. Shocks due to defective wiring in home appliances or other electrical equipment can cause severe burns, even death. As a result, the National Electrical Code now requires GFIs in all new homes constructed. This particular type of GFI employs a sensing element which derives from technology acquired in space projects by SCI Systems, Inc., Huntsville, Alabama, producer of sensors for GE and other manufacturers of GFI equipment. The sensor is based on the company's experience in developing miniaturized circuitry for space telemetry and other spacecraft electrical systems; this experience enabled SCI to package interruptor circuitry in the extremely limited space available and to produce sensory devices at practicable cost. The tiny sensor measures the strength of the electrical current and detects current differentials that indicate a fault in the functioning of an electrical system. The sensing element then triggers a signal to a disconnect mechanism in the GFI, which cuts off the current in the faulty circuit.

  13. Astrophysical disks Collective and Stochastic Phenomena

    CERN Document Server

    Fridman, Alexei M; Kovalenko, Ilya G

    2006-01-01

    The book deals with collective and stochastic processes in astrophysical discs involving theory, observations, and the results of modelling. Among others, it examines the spiral-vortex structure in galactic and accretion disks , stochastic and ordered structures in the developed turbulence. It also describes sources of turbulence in the accretion disks, internal structure of disk in the vicinity of a black hole, numerical modelling of Be envelopes in binaries, gaseous disks in spiral galaxies with shock waves formation, observation of accretion disks in a binary system and mass distribution of luminous matter in disk galaxies. The editors adaptly brought together collective and stochastic phenomena in the modern field of astrophysical discs, their formation, structure, and evolution involving the methodology to deal with, the results of observation and modelling, thereby advancing the study in this important branch of astrophysics and benefiting Professional Researchers, Lecturers, and Graduate Students.

  14. Shock Wave Science and Technology Reference Library

    CERN Document Server

    2007-01-01

    Shock waves in multiphase flows refers to a rich variety of phenomena of interest to physicists, chemists, and fluid dynamicists, as well as mechanical, biomedical and aeronautical engineers. This volume treats shock and expansion waves in (bullet) complex, bubbly liquids (L van Wijngaarden, Y Tomita, V Kedrinskii) and (bullet) cryogenic liquids (M Murakami) and examines the relationship of shock waves with (bullet) phase transitions (A Guha, CF Delale, G Schnerr, MEH van Dongen) (bullet) induced phase transitions (GEA Meier) as well as their interaction with (bullet) solid foams, textiles, porous and granular media (B Skews, DMJ Smeulders, MEH van Dongen, V Golub, O Mirova) All chapters are self-contained, so they can be read independently, although they are of course thematically interrelated. Taken together, they offer a timely reference on shock waves in multiphase flows, including new viewpoints and burgeoning developments. The book will appeal to beginners as well as professional scientists and engineer...

  15. Condensed matter at high shock pressures

    Energy Technology Data Exchange (ETDEWEB)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-07-12

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab.

  16. PENETRATION OF A SHOCK WAVE IN A FLAME FRONT

    Directory of Open Access Journals (Sweden)

    Dan PANTAZOPOL

    2009-09-01

    Full Text Available The present paper deals with the interactions between a fully supersonic flame front, situated in a supersonic two-dimensional flow of an ideal homogeneous combustible gas mixture, and an incident shock wawe, which is penetrating in the space of the hot burnt gases. A possible configuration, which was named ,,simple penetration” is examined. For the anlysis of the interference phenomena, shock polar and shock-combustion polar are used. At the same time, the paper shows the possibility to produce similar but more complicated configurations, which may contain expansion fans and reflected shock waves.

  17. Nuclear fuel deformation phenomena

    International Nuclear Information System (INIS)

    Van Brutzel, L.; Dingreville, R.; Bartel, T.J.

    2015-01-01

    Nuclear fuel encounters severe thermomechanical environments. Its mechanical response is profoundly influenced by an underlying heterogeneous microstructure but also inherently dependent on the temperature and stress level histories. The ability to adequately simulate the response of such microstructures, to elucidate the associated macroscopic response in such extreme environments is crucial for predicting both performance and transient fuel mechanical responses. This chapter discusses key physical phenomena and the status of current modelling techniques to evaluate and predict fuel deformations: creep, swelling, cracking and pellet-clad interaction. This chapter only deals with nuclear fuel; deformations of cladding materials are discussed elsewhere. An obvious need for a multi-physics and multi-scale approach to develop a fundamental understanding of properties of complex nuclear fuel materials is presented. The development of such advanced multi-scale mechanistic frameworks should include either an explicit (domain decomposition, homogenisation, etc.) or implicit (scaling laws, hand-shaking,...) linkage between the different time and length scales involved, in order to accurately predict the fuel thermomechanical response for a wide range of operating conditions and fuel types (including Gen-IV and TRU). (authors)

  18. Arcjet cathode phenomena

    Science.gov (United States)

    Curran, Francis M.; Haag, Thomas W.; Raquet, John F.

    1989-01-01

    Cathode tips made from a number of different materials were tested in a modular arcjet thruster in order to examine cathode phenomena. Periodic disassembly and examination, along with the data collected during testing, indicated that all of the tungsten-based materials behaved similarly despite the fact that in one of these samples the percentage of thorium oxide was doubled and another was 25 percent rhenium. The mass loss rate from a 2 percent thoriated rhenium cathode was found to be an order of magnitude greater than that observed using 2 percent thoriated tungsten. Detailed analysis of one of these cathode tips showed that the molten crater contained pure tungsten to a depth of about 150 microns. Problems with thermal stress cracking were encountered in the testing of a hafnium carbide tip. Post test analysis showed that the active area of the tip had chemically reacted with the propellant. A 100 hour continuous test was run at about 1 kW. Post test analysis revealed no dendrite formation, such as observed in a 30 kW arcjet lifetest, near the cathode crater. The cathodes from both this test and a previously run 1000 hour cycled test displayed nearly identical arc craters. Data and calculations indicate that the mass losses observed in testing can be explained by evaporation.

  19. Acid Deposition Phenomena

    International Nuclear Information System (INIS)

    Ramadan, A.E.K.

    2004-01-01

    Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H 2 SO 4 ) and nitric acids (HNO 3 ), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry

  20. The ''injection problem'' for quasiparallel shocks

    International Nuclear Information System (INIS)

    Zank, G. P.; Rice, W. K. M.; le Roux, J. A.; Cairns, I. H.; Webb, G. M.

    2001-01-01

    For a particle to be accelerated diffusively at a shock by the first-order Fermi acceleration mechanism, the particle must be sufficiently energetic that it can scatter across all the micro- and macrostructure of the shock, experiencing compression between the converging upstream and downstream states. This is the well-known ''injection problem.'' Here the interaction of ions with the ramp of a quasiparallel shock is investigated. Some ions incident on the shock experience specular reflection, caused either by the cross-shock electrostatic potential or by mirroring as the magnetic field is bent and compressed through the ramp. Scattering of reflected ions by self-generated and pre-existing turbulence in the region upstream of the shock then acts to trap backstreaming ions and return them to the ramp, where some experience further reflections. Such repeated reflections and scattering energize a subpopulation of ions up to energies sufficiently large that they can be diffusively shock accelerated. Two ion distributions are considered: pickup ions which are assumed to be described by a shell distribution, are thermal solar wind ions which may be described by a kappa distribution. Injection efficiencies are found analytically to be very high for pickup ions and much lower for thermal solar wind ions, suggesting that this injection mechanism, stochastic reflected ion or SRI acceleration, is a natural precursor for the acceleration of the anomalous cosmic ray component at a quasiparallel shock. While significantly less efficient, SRI acceleration is also viable for thermal solar wind ions described by a kappa distribution

  1. Hysteresis phenomena in hydraulic measurement

    International Nuclear Information System (INIS)

    Ran, H J; Farhat, M; Luo, X W; Chen, Y L; Xu, H Y

    2012-01-01

    Hysteresis phenomena demonstrate the lag between the generation and the removal of some physical phenomena. This paper studies the hysteresis phenomena of the head-drop in a scaled model pump turbine using experiment test and CFD methods. These lag is induced by complicated flow patterns, which influenced the reliability of rotating machine. Keeping the same measurement procedure is concluded for the hydraulic machine measurement.

  2. Haters Phenomena in Social Media

    OpenAIRE

    Pradipta, Angga; Lailiyah, S.Sos, M.I.Kom, Nuriyatul

    2016-01-01

    Social media is internet-basic media, functioned as interaction media room based on multimedia technology. And social media created some effects. One of the negative effects of social media is haters phenomena. Haters are a person who easily said dirty words, harass, and humiliate to others. This phenomena causes anxiety—especially in Indonesia, even the Government issued public policy and letter of regulation about this phenomena, through Paragraph 27 verse (3) IT Constitution, Paragraph 45 ...

  3. Transport phenomena in environmental engineering

    Science.gov (United States)

    Sander, Aleksandra; Kardum, Jasna Prlić; Matijašić, Gordana; Žižek, Krunoslav

    2018-01-01

    A term transport phenomena arises as a second paradigm at the end of 1950s with high awareness that there was a strong need to improve the scoping of chemical engineering science. At that point, engineers became highly aware that it is extremely important to take step forward from pure empirical description and the concept of unit operations only to understand the specific process using phenomenological equations that rely on three elementary physical processes: momentum, energy and mass transport. This conceptual evolution of chemical engineering was first presented with a well-known book of R. Byron Bird, Warren E. Stewart and Edwin N. Lightfoot, Transport Phenomena, published in 1960 [1]. What transport phenomena are included in environmental engineering? It is hard to divide those phenomena through different engineering disciplines. The core is the same but the focus changes. Intention of the authors here is to present the transport phenomena that are omnipresent in treatment of various process streams. The focus in this chapter is made on the transport phenomena that permanently occur in mechanical macroprocesses of sedimentation and filtration for separation in solid-liquid particulate systems and on the phenomena of the flow through a fixed and a fluidized bed of particles that are immanent in separation processes in packed columns and in environmental catalysis. The fundamental phenomena for each thermal and equilibrium separation process technology are presented as well. Understanding and mathematical description of underlying transport phenomena result in scoping the separation processes in a way that ChEs should act worldwide.

  4. Shock interactions with heterogeneous energetic materials

    Science.gov (United States)

    Yarrington, Cole D.; Wixom, Ryan R.; Damm, David L.

    2018-03-01

    The complex physical phenomenon of shock wave interaction with material heterogeneities has significant importance and nevertheless remains little understood. In many materials, the observed macroscale response to shock loading is governed by characteristics of the microstructure. Yet, the majority of computational studies aimed at predicting phenomena affected by these processes, such as the initiation and propagation of detonation waves in explosives or shock propagation in geological materials, employ continuum material and reactive burn model treatment. In an effort to highlight the grain-scale processes that underlie the observable effects in an energetic system, a grain-scale model for hexanitrostilbene (HNS) has been developed. The measured microstructures were used to produce synthetic computational representations of the pore structure, and a density functional theory molecular dynamics derived equation of state (EOS) was used for the fully dense HNS matrix. The explicit inclusion of the microstructure along with a fully dense EOS resulted in close agreement with historical shock compression experiments. More recent experiments on the dynamic reaction threshold were also reproduced by inclusion of a global kinetics model. The complete model was shown to reproduce accurately the expected response of this heterogeneous material to shock loading. Mesoscale simulations were shown to provide a clear insight into the nature of threshold behavior and are a way to understand complex physical phenomena.

  5. Simulations of Biomechanical Phenomena

    Science.gov (United States)

    Gonzalez, Jose Cruz

    Recent studies have published breakthroughs in the application of finite element (FEA) studies in the design and analysis of advanced orthodontics. However, FEA has not captured bone remodeling responses to advanced orthodontics. The results of these simulations report unrealistic displacement around the nasal bridge, which impeded correlation with clinical data. Bone remodeling has been previously documented in FEA and has shown bone response to mechanical stimulus in femur bone models. However, the relationship between mechanical stimulus and bone remodeling has not been reported in orthodontic studies due to the complexity of the skull. In the current study, strain energy is used as the mechanical stimulus to control remodeling, from which density and modulus evolve. Due to the localization of forces in orthodontics, current remodeling algorithms have limited application. In turn, we developed an algorithm that dynamically collects, sorts, and bins stresses in all elements for regional remodeling based on the proximity of the element to the load. The results demonstrate that bone response to orthodontic appliances is different than that of an FEA without bone remodeling, due to load path changes based upon evolution of the bone properties. It was also found that density and moduli proximal to the load application site exhibit faster remodeling than those located remotely. Modeling another biomechanical phenomena, a 3D simulation was created to simulate recent experimental results that discovered a difference in impact mitigation properties of dense-polymer/foam bilayer structure based on the orientation of the dense-polymer with respect to the impact site. The impact energy transmitted varied in time of arrival and amplitude depending on the orientation of the structure (thin layer up or down). By creating a 3D explicit dynamic FEA simulation, it is expected to reduce costly experiments and time consumed in set up, and offer opportunities for optimization for

  6. EXPERIMENTAL STUDY OF SHOCK WAVE DYNAMICS IN MAGNETIZED PLASMAS

    International Nuclear Information System (INIS)

    Podder, Nirmol K.

    2009-01-01

    In this four-year project (including one-year extension), the project director and his research team built a shock-wave-plasma apparatus to study shock wave dynamics in glow discharge plasmas in nitrogen and argon at medium pressure (1-20 Torr), carried out various plasma and shock diagnostics and measurements that lead to increased understanding of the shock wave acceleration phenomena in plasmas. The measurements clearly show that in the steady-state dc glow discharge plasma, at fixed gas pressure the shock wave velocity increases, its amplitude decreases, and the shock wave disperses non-linearly as a function of the plasma current. In the pulsed discharge plasma, at fixed gas pressure the shock wave dispersion width and velocity increase as a function of the delay between the switch-on of the plasma and shock-launch. In the afterglow plasma, at fixed gas pressure the shock wave dispersion width and velocity decrease as a function of the delay between the plasma switch-off and shock-launch. These changes are found to be opposite and reversing towards the room temperature value which is the initial condition for plasma ignition case. The observed shock wave properties in both igniting and afterglow plasmas correlate well with the inferred temperature changes in the two plasmas

  7. Collisionless electrostatic shocks

    DEFF Research Database (Denmark)

    Andersen, H.K.; Andersen, S.A.; Jensen, Vagn Orla

    1970-01-01

    An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth......An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth...

  8. Introductory lectures on critical phenomena

    International Nuclear Information System (INIS)

    Khajehpour, M.R.H.

    1988-09-01

    After a presentation of classical models for phase transitions and critical phenomena (Van der Waals theory, Weiss theory of ferromagnetism) and theoretical models (Ising model, XY model, Heisenberg model, spherical model) the Landau theory of critical and multicritical points and some single applications of renormalization group method in static critical phenomena are presented. 115 refs, figs and tabs

  9. Transient shock waves in heliosphere and Sun-Earth relations

    International Nuclear Information System (INIS)

    Voeroes, Z.

    1990-01-01

    The problem of shock waves, caused by solar activity in the Earth's magnetosphere and its magnetic field, is discussed. All types of shock waves have their origin either in solar corona effects or in solar eruptions. Ionospheric and magnetospheric effects, such as X and gamma radiation, particle production, geomagnetic storms and shock waves, caused by solar activity, are dealt with and attempts are made to explain their interdependence. The origin and propagation of coronal shock waves, interplanetary shock waves and geomagnetic field disorders are described and their relations discussed. The understanding of the solar corona and wind phenomena seems to allow prediction of geomagnetic storms. The measurement and analysis of solar activity and its effects could yield useful information about shock waves physics, geomagnetosphere structure and relations between the Earth and the Sun. (J.J.). 7 figs., 1 tab., 37 refs

  10. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

    2016-01-01

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  11. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.

    2016-12-12

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  12. Psychospiritual Resiliency: Enhancing Mental Health and Ecclesiastical Collaboration in Caring for Those Experiencing Dissociative Phenomena.

    Science.gov (United States)

    Howard, Christopher J

    2017-02-01

    Trauma can oftentimes be a catalyst for changes in an individual's religious and spiritual beliefs. Beliefs about the cause of the trauma, for instance, may include attributions of possessing spirits, and are to be found in an increasingly pluralistic and multicultural society. Such preternatural explanations may be referred to as dissociative identity disorder, possession form. Unwittingly, an overreliance on neurobiological explanations and relegation of cultural idioms of distress may diminish effective collaboration with ecclesiastical authorities. Concomitantly, ecclesiastical experts are confronted with bewildering posttrauma dissociative symptomatology, and may not be prepared as diagnosticians to rule out psychobiological explanations. In both instances, client care may be compromised. Noteworthy, the current investigation integrates the author's participant observation research at the Vatican's school of Exorcism in Rome, Italy.

  13. Dative experiencer predicates in Hungarian

    NARCIS (Netherlands)

    Rákosi, G.

    2006-01-01

    Dative experiencer predicates in Hungarian investigates the argument structure and the syntax of appeal to- and important-type predicates in Hungarian. Couched in terms of Reinhart’s (2000, 2002) Theta System, the thesis presents arguments for the need to resort to the lexicon in setting up

  14. Advanced diffusion processes and phenomena

    CERN Document Server

    Öchsner, Andreas; Belova, Irina

    2014-01-01

    This topical volume on Advanced Diffusion Processes and Phenomena addresses diffusion in a wider sense of not only mass diffusion but also heat diffusion in fluids and solids. Both diffusion phenomena play an important role in the characterization of engineering materials and corresponding structures. Understanding these different transport phenomena at many levels, from atomistic to macro, has therefore long attracted the attention of many researchers in materials science and engineering and related disciplines. The present topical volume captures a representative cross-section of some of the

  15. Kinetic effects on magnetohydrodynamic phenomena

    International Nuclear Information System (INIS)

    Naito, Hiroshi; Matsumoto, Taro

    2001-01-01

    Resistive and ideal magnetohydrodynamic (MHD) theories are insufficient to adequately explain MHD phenomena in the high-temperature plasma. Recent progress in numerical simulations concerning kinetic effects on magnetohydrodynamic phenomena is summarized. The following three topics are studied using various models treating extended-MHD phenomena. (1) Kinetic modifications of internal kink modes in tokamaks with normal and reversed magnetic shear configurations. (2) Temporal evolution of the toroidal Alfven eigenmode and fishbone mode in tokamaks with energetic ions. (3) Kinetic stabilization of a title mode in field-reversed configurations by means of anchoring ions and beam ions. (author)

  16. Ductile fracture estimation of reactor pressure vessel under thermal shock

    International Nuclear Information System (INIS)

    Takahashi, Jun; Sakai, Shinsuke; Okamura, Hiroyuki

    1990-01-01

    This paper presents a new scheme for the estimation of unstable ductile fracture of a reactor pressure vessel under thermal shock conditions. First, it is shown that the bending moment applied to the cracked section can be evaluated by considering the plastic deformation of the cracked section and the thermal deformation of the shell. As the contribution of the local thermal stress to the J-value is negligible, the J-value under thermal shock can be easily evaluated by using fully plastic solutions for the cracked part. Next, the phenomena of ductile fracture under thermal shock are expressed on the load-versus-displacement diagram which enables us to grasp the transient phenomena visually. In addition, several parametrical surveys are performed on the above diagram concerning the variation of (1) thermal shock conditions, (2) initial crack length, and (3) J-resistance curve (i.e. embrittlement by neutron irradiation). (author)

  17. Micro transport phenomena during boiling

    CERN Document Server

    Peng, Xiaofeng

    2011-01-01

    "Micro Transport Phenomena During Boiling" reviews the new achievements and contributions in recent investigations at microscale. It presents some original research results and discusses topics at the frontier of thermal and fluid sciences.

  18. Mixed Fluid Conditions: Capillary Phenomena

    KAUST Repository

    Santamarina, Carlos; Sun, Zhonghao

    2017-01-01

    Mixed fluid phenomena in porous media have profound implications on soil-atmosphere interaction, energy geotechnology, environmental engineering and infrastructure design. Surface tension varies with pressure, temperature, solute concentration

  19. Renormalization group and critical phenomena

    International Nuclear Information System (INIS)

    Ji Qing

    2004-01-01

    The basic clue and the main steps of renormalization group method used for the description of critical phenomena is introduced. It is pointed out that this method really reflects the most important physical features of critical phenomena, i.e. self-similarity, and set up a practical solving method from it. This way of setting up a theory according to the features of the physical system is really a good lesson for today's physicists. (author)

  20. Hypnagogic and hypnopompic hallucinations: pathological phenomena?

    Science.gov (United States)

    Ohayon, M M; Priest, R G; Caulet, M; Guilleminault, C

    1996-10-01

    Hypnagogic and hypnopompic hallucinations are common in narcolepsy. However, the prevalence of these phenomena in the general population is uncertain. A representative community sample of 4972 people in the UK, aged 15-100, was interviewed by telephone (79.6% of those contacted). Interviews were performed by lay interviewers using a computerised system that guided the interviewer through the interview process. Thirty-seven per cent of the sample reported experiencing hypnagogic hallucinations and 12.5% reported hypnopompic hallucinations. Both types of hallucinations were significantly more common among subjects with symptoms of insomnia, excessive daytime sleepiness or mental disorders. According to this study, the prevalence of narcolepsy in the UK is 0.04%. Hypnagogic and hypnopompic hallucinations were much more common than expected, with a prevalence that far exceeds that which can be explained by the association with narcolepsy. Hypnopompic hallucinations may be a better indicator of narcolepsy than hypnagogic hallucinations in subjects reporting excessive daytime sleepiness.

  1. Shock wave science and technology reference library

    CERN Document Server

    2009-01-01

    This book is the second of several volumes on solids in the Shock Wave Science and Technology Reference Library. These volumes are primarily concerned with high-pressure shock waves in solid media, including detonation and high-velocity impact and penetration events. Of the four extensive chapters in this volume, the first two describe the reactive behavior of condensed phase explosives, - Condensed-Phase Explosives: Shock Initiation and Detonation Phenomena (SA Sheffield and R Engelke) - First Principles Molecular Simulations of Energetic Materials at High-Pressures (F Zhang, S Alavi, and TK Woo), and the remaining two discuss the inert, mechanical response of solid materials. - Combined Compression and Shear Plane Waves (ZP Tang and JB Aidun), and - Dynamic Fragmentation of Solids (D Grady). All chapters are each self-contained, and can be read independently of each other. They offer a timely reference, for beginners as well as professional scientists and engineers, on the foundations of detonation phenomen...

  2. Miniature shock tube for laser driven shocks.

    Science.gov (United States)

    Busquet, Michel; Barroso, Patrice; Melse, Thierry; Bauduin, Daniel

    2010-02-01

    We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."

  3. Are Credit Shocks Supply or Demand Shocks?

    OpenAIRE

    Bijapur, Mohan

    2013-01-01

    This paper provides new insights into the relationship between the supply of credit and the macroeconomy. We present evidence that credit shocks constitute shocks to aggregate supply in that they have a permanent effect on output and cause inflation to rise in the short term. Our results also suggest that the effects on aggregate supply have grown stronger in recent decades.

  4. Shock absorbing structure

    International Nuclear Information System (INIS)

    Kojima, Naoki; Matsushita, Kazuo.

    1992-01-01

    Small pieces of shock absorbers are filled in a space of a shock absorbing vessel which is divided into a plurality of sections by partitioning members. These sections function to prevent excess deformation or replacement of the fillers upon occurrence of falling accident. Since the shock absorbing small pieces in the shock absorbing vessel are filled irregularly, shock absorbing characteristics such as compression strength is not varied depending on the direction, but they exhibit excellent shock absorbing performance. They surely absorb shocks exerted on a transportation vessel upon falling or the like. If existing artificial fillers such as pole rings made of metal or ceramic and cut pieces such as alumium extrusion molding products are used as the shock absorbing pieces, they have excellent fire-proofness and cold resistance since the small pieces are inflammable and do not contain water. (T.M.)

  5. Melting under shock compression

    International Nuclear Information System (INIS)

    Bennett, B.I.

    1980-10-01

    A simple model, using experimentally measured shock and particle velocities, is applied to the Lindemann melting formula to predict the density, temperature, and pressure at which a material will melt when shocked from room temperature and zero pressure initial conditions

  6. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  7. Relativistic Shock Acceleration

    International Nuclear Information System (INIS)

    Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

    1999-01-01

    In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

  8. Particle acceleration by coronal and interplanetary shock waves

    International Nuclear Information System (INIS)

    Pesses, M.E.

    1982-01-01

    Utilizing many years of observation from deep space and near-earth spacecraft a theoretical understanding has evolved on how ions and electrons are accelerated in interplanetary shock waves. This understanding is now being applied to solar flare-induced shock waves propagating through the solar atmosphere. Such solar flare phenomena as gamma-ray line and neutron emissions, interplanetary energetic electron and ion events, and Type II and moving Type IV radio bursts appear understandable in terms of particle acceleration in shock waves

  9. Containment severe accident thermohydraulic phenomena

    International Nuclear Information System (INIS)

    Frid, W.

    1991-08-01

    This report describes and discusses the containment accident progression and the important severe accident containment thermohydraulic phenomena. The overall objective of the report is to provide a rather detailed presentation of the present status of phenomenological knowledge, including an account of relevant experimental investigations and to discuss, to some extent, the modelling approach used in the MAAP 3.0 computer code. The MAAP code has been used in Sweden as the main tool in the analysis of severe accidents. The dependence of the containment accident progression and containment phenomena on the initial conditions, which in turn are heavily dependent on the in-vessel accident progression and phenomena as well as associated uncertainties, is emphasized. The report is in three parts dealing with: * Swedish reactor containments, the severe accident mitigation programme in Sweden and containment accident progression in Swedish PWRs and BWRs as predicted by the MAAP 3.0 code. * Key non-energetic ex-vessel phenomena (melt fragmentation in water, melt quenching and coolability, core-concrete interaction and high temperature in containment). * Early containment threats due to energetic events (hydrogen combustion, high pressure melt ejection and direct containment heating, and ex-vessel steam explosions). The report concludes that our understanding of the containment severe accident progression and phenomena has improved very significantly over the parts ten years and, thereby, our ability to assess containment threats, to quantify uncertainties, and to interpret the results of experiments and computer code calculations have also increased. (au)

  10. Teaching optical phenomena with Tracker

    Science.gov (United States)

    Rodrigues, M.; Simeão Carvalho, P.

    2014-11-01

    Since the invention and dissemination of domestic laser pointers, observing optical phenomena is a relatively easy task. Any student can buy a laser and experience at home, in a qualitative way, the reflection, refraction and even diffraction phenomena of light. However, quantitative experiments need instruments of high precision that have a relatively complex setup. Fortunately, nowadays it is possible to analyse optical phenomena in a simple and quantitative way using the freeware video analysis software ‘Tracker’. In this paper, we show the advantages of video-based experimental activities for teaching concepts in optics. We intend to show: (a) how easy the study of such phenomena can be, even at home, because only simple materials are needed, and Tracker provides the necessary measuring instruments; and (b) how we can use Tracker to improve students’ understanding of some optical concepts. We give examples using video modelling to study the laws of reflection, Snell’s laws, focal distances in lenses and mirrors, and diffraction phenomena, which we hope will motivate teachers to implement it in their own classes and schools.

  11. A model for radio emission from solar coronal shocks

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, G. Q.; Chen, L.; Wu, D. J., E-mail: djwu@pmo.ac.cn [Purple Mountain Observatory, CAS, Nanjing 210008 (China)

    2014-05-01

    Solar coronal shocks are very common phenomena in the solar atmosphere and are believed to be the drivers of solar type II radio bursts. However, the microphysical nature of these emissions is still an open question. This paper proposes that electron cyclotron maser (ECM) emission is responsible for the generation of radiation from the coronal shocks. In the present model, an energetic ion beam accelerated by the shock first excites the Alfvén wave (AW), then the excited AW leads to the formation of a density-depleted duct along the foreshock boundary of the shock. In this density-depleted duct, the energetic electron beam produced via the shock acceleration can effectively excite radio emission by ECM instability. Our results show that this model may potentially be applied to solar type II radio bursts.

  12. A model for radio emission from solar coronal shocks

    International Nuclear Information System (INIS)

    Zhao, G. Q.; Chen, L.; Wu, D. J.

    2014-01-01

    Solar coronal shocks are very common phenomena in the solar atmosphere and are believed to be the drivers of solar type II radio bursts. However, the microphysical nature of these emissions is still an open question. This paper proposes that electron cyclotron maser (ECM) emission is responsible for the generation of radiation from the coronal shocks. In the present model, an energetic ion beam accelerated by the shock first excites the Alfvén wave (AW), then the excited AW leads to the formation of a density-depleted duct along the foreshock boundary of the shock. In this density-depleted duct, the energetic electron beam produced via the shock acceleration can effectively excite radio emission by ECM instability. Our results show that this model may potentially be applied to solar type II radio bursts.

  13. Critical Phenomena in Gravitational Collapse

    Directory of Open Access Journals (Sweden)

    Gundlach Carsten

    1999-01-01

    Full Text Available As first discovered by Choptuik, the black hole threshold in the space of initial data for general relativity shows both surprising structure and surprising simplicity. Universality, power-law scaling of the black hole mass, and scale echoing have given rise to the term 'critical phenomena'. They are explained by the existence of exact solutions which are attractors within the black hole threshold, that is, attractors of codimension one in phase space, and which are typically self-similar. This review gives an introduction to the phenomena, tries to summarize the essential features of what is happening, and then presents extensions and applications of this basic scenario. Critical phenomena are of interest particularly for creating surprising structure from simple equations, and for the light they throw on cosmic censorship and the generic dynamics of general relativity.

  14. Especial Skills in Experienced Archers.

    Science.gov (United States)

    Nabavinik, Mahdi; Abaszadeh, Ali; Mehranmanesh, Mehrab; Rosenbaum, David A

    2017-09-05

    Especial skills are skills that are distinctive by virtue of massive practice within the narrow contexts in which they are expressed. In the first demonstration of especial skills, Keetch, Schmidt, Lee, and Young (2005) showed that experienced basketball players are better at shooting baskets from the foul line, where they had massive amounts of practice, than would expected from their success at other locations closer to or farther from the basket. Similar results were obtained for baseball throwing. The authors asked whether especial skills hold in archery, a sport requiring less movement. If the emergence of especial skills depends on large-scale movement, one would expect archery to escape so-called especialism. But if the emergence of especial skills reflects a more general tendency for highly specific learning, experienced archers should show especial skills. The authors obtained evidence consistent with the latter prediction. The expert archers did much better at their most highly practiced distance than would be expected by looking at the overall function relating shooting score to distance. We offer a mathematical model to account for this result. The findings attest to the generality of the especial skills phenomenon.

  15. Vorticity dynamics after the shock-turbulence interaction

    Science.gov (United States)

    Livescu, D.; Ryu, J.

    2016-05-01

    The interaction of a shock wave with quasi-vortical isotropic turbulence (IT) represents a basic problem for studying some of the phenomena associated with high speed flows, such as hypersonic flight, supersonic combustion and Inertial Confinement Fusion (ICF). In general, in practical applications, the shock width is much smaller than the turbulence scales and the upstream turbulent Mach number is modest. In this case, recent high resolution shock-resolved Direct Numerical Simulations (DNS) (Ryu and Livescu, J Fluid Mech 756:R1, 2014) show that the interaction can be described by the Linear Interaction Approximation (LIA). Using LIA to alleviate the need to resolve the shock, DNS post-shock data can be generated at much higher Reynolds numbers than previously possible. Here, such results with Taylor Reynolds number approximately 180 are used to investigate the changes in the vortical structure as a function of the shock Mach number, Ms, up to Ms=10. It is shown that, as Ms increases, the shock interaction induces a tendency towards a local axisymmetric state perpendicular to the shock front, which has a profound influence on the vortex-stretching mechanism and divergence of the Lamb vector and, ultimately, on the flow evolution away from the shock.

  16. Abnormal pressures as hydrodynamic phenomena

    Science.gov (United States)

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  17. Whistlers and related ionospheric phenomena

    CERN Document Server

    Helliwell, Robert A

    2006-01-01

    The investigation of whistlers and related phenomena is a key element in studies of very-low-frequency propagation, satellite communication, the outer ionosphere, and solar-terrestrial relationships. This comprehensive text presents a history of the study of the phenomena and includes all the elements necessary for the calculation of the characteristics of whistlers and whistler-mode signals.An introduction and brief history are followed by a summary of the theory of whistlers and a detailed explanation of the calculation of their characteristics. Succeeding chapters offer a complete atlas of

  18. Presentation and representation of biological phenomena from a vegetable garden

    Directory of Open Access Journals (Sweden)

    Ana Maria de Andrade Caldeira

    2007-08-01

    Full Text Available This paper proposes a methodology for science education based on the triad perceive/associate/experience. The analysis performed relied upon Charles Sanders Peirce’s semiotics framework. The research was develop at elementary school (nine-yar old students showing that the described methodology enable them the students to percieve, to set up relationships and to experience the natural phenomena, built up from the experienced sequences.

  19. Pressurized thermal shock (PTS)

    International Nuclear Information System (INIS)

    Rosso, Ricardo D.; Ventura, Mirta A.

    2006-01-01

    In the present work, a description of Thermal Shock in Pressurized conditions (PTS), and its influence in the treatment of the integrity of the pressure vessel (RPV) of a Pressurized Water Reactor (PWR) and/or of a Heavy water Pressurized water Reactor (PHWR) is made. Generally, the analysis of PTS involves a process of three stages: a-) Modeling with a System Code of relevant thermohydraulics transients in reference with the thermal shock; b-) The local distribution of temperatures in the downcomer and the heat transference coefficients from the RPV wall to the fluid, are determined; c-) The fracture mechanical analysis. These three stages are included in this work: Results with the thermohydraulics code Relap5/mod.3, are obtained, for a LOCA scenario in the hot leg of the cooling System of the Primary System of the CAN-I reactor. The method used in obtaining results is described. A study on the basis of lumped parameters of the local evolutions of the temperature of the flow is made, in the downcomer of the reactor pressure vessel. The purpose of this study is to determine how the intensification of the stress coefficient, varies in function of the emergency injected water during the thermohydraulic transients that take place under the imposed conditions in the postulated scene. Specially, it is considered a 50 cm 2 break, located in the neighborhoods of the pressurized with the corresponding hot leg connection. This size is considered like the most critical. The method used to obtain the results is described. The fracture mechanical analysis is made. From the obtained results we confirmed that we have a simple tool of easy application in order to analyze phenomena of the type PTS in the postulated scenes by break in the cold and hot legs of the primary system. This methodology of calculus is completely independent of the used ones by the Nucleoelectrica Argentina S.A. (NASA) in the analysis of the PTS phenomena in the CAN-I. The results obtained with the adopted

  20. Alfven shock trains

    International Nuclear Information System (INIS)

    Malkov, M.A.; Kennel, C.F.; Wu, C.C.; Pellat, R.; Shapiro, V.D.

    1991-01-01

    The Cohen--Kulsrud--Burgers equation (CKB) is used to consider the nonlinear evolution of resistive, quasiparallel Alfven waves subject to a long-wavelength, plane-polarized, monochromatic instability. The instability saturates by nonlinear steepening, which proceeds until the periodic waveform develops an interior scale length comparable to the dissipation length; a fast or an intermediate shock then forms. The result is a periodic train of Alfven shocks of one or the other type. For propagation strictly parallel to the magnetic field, there will be two shocks per instability wavelength. Numerical integration of the time-dependent CKB equation shows that an initial, small-amplitude growing wave asymptotes to a stable, periodic stationary wave whose analytic solution specifies how the type of shock embedded in the shock train, and the amplitude and speed of the shock train, depend on the strength and phase of the instability. Waveforms observed upstream of the Earth's bowshock and cometary shocks resemble those calculated here

  1. Experiencing Security in Interaction Design

    DEFF Research Database (Denmark)

    Mathiasen, Niels Raabjerg; Bødker, Susanne

    2011-01-01

    Security is experienced differently in different contexts. This paper argues that in everyday situations, users base their security decisions on a mix of prior experiences. When approaching security and interaction design from an experience approach, tools that help bring out such relevant...... experiences for design are needed. This paper reports on how Prompted exploration workshops and Acting out security were developed to target such experiences when iteratively designing a mobile digital signature solution in a participatory design process. We discuss how these tools helped the design process...... and illustrate how the tangibility of such tools matters. We further demonstrate how the approach grants access to non-trivial insights into people's security experience. We point out how the specific context is essential for exploring the space between experience and expectations, and we illustrate how people...

  2. Interoceptive awareness in experienced meditators.

    Science.gov (United States)

    Khalsa, Sahib S; Rudrauf, David; Damasio, Antonio R; Davidson, Richard J; Lutz, Antoine; Tranel, Daniel

    2008-07-01

    Attention to internal body sensations is practiced in most meditation traditions. Many traditions state that this practice results in increased awareness of internal body sensations, but scientific studies evaluating this claim are lacking. We predicted that experienced meditators would display performance superior to that of nonmeditators on heartbeat detection, a standard noninvasive measure of resting interoceptive awareness. We compared two groups of meditators (Tibetan Buddhist and Kundalini) to an age- and body mass index-matched group of nonmeditators. Contrary to our prediction, we found no evidence that meditators were superior to nonmeditators in the heartbeat detection task, across several sessions and respiratory modulation conditions. Compared to nonmeditators, however, meditators consistently rated their interoceptive performance as superior and the difficulty of the task as easier. These results provide evidence against the notion that practicing attention to internal body sensations, a core feature of meditation, enhances the ability to sense the heartbeat at rest.

  3. Customer-experienced rapid prototyping

    Science.gov (United States)

    Zhang, Lijuan; Zhang, Fu; Li, Anbo

    2008-12-01

    In order to describe accurately and comprehend quickly the perfect GIS requirements, this article will integrate the ideas of QFD (Quality Function Deployment) and UML (Unified Modeling Language), and analyze the deficiency of prototype development model, and will propose the idea of the Customer-Experienced Rapid Prototyping (CE-RP) and describe in detail the process and framework of the CE-RP, from the angle of the characteristics of Modern-GIS. The CE-RP is mainly composed of Customer Tool-Sets (CTS), Developer Tool-Sets (DTS) and Barrier-Free Semantic Interpreter (BF-SI) and performed by two roles of customer and developer. The main purpose of the CE-RP is to produce the unified and authorized requirements data models between customer and software developer.

  4. Maxwell Prize Talk: Scaling Laws for the Dynamical Plasma Phenomena

    Science.gov (United States)

    Ryutov, Livermore, Ca 94550, Usa, D. D.

    2017-10-01

    The scaling and similarity technique is a powerful tool for developing and testing reduced models of complex phenomena, including plasma phenomena. The technique has been successfully used in identifying appropriate simplified models of transport in quasistationary plasmas. In this talk, the similarity and scaling arguments will be applied to highly dynamical systems, in which temporal evolution of the plasma leads to a significant change of plasma dimensions, shapes, densities, and other parameters with respect to initial state. The scaling and similarity techniques for dynamical plasma systems will be presented as a set of case studies of problems from various domains of the plasma physics, beginning with collisonless plasmas, through intermediate collisionalities, to highly collisional plasmas describable by the single-fluid MHD. Basic concepts of the similarity theory will be introduced along the way. Among the results discussed are: self-similarity of Langmuir turbulence driven by a hot electron cloud expanding into a cold background plasma; generation of particle beams in disrupting pinches; interference between collisionless and collisional phenomena in the shock physics; similarity for liner-imploded plasmas; MHD similarities with an emphasis on the effect of small-scale (turbulent) structures on global dynamics. Relations between astrophysical phenomena and scaled laboratory experiments will be discussed.

  5. Transport phenomena in particulate systems

    CERN Document Server

    Freire, José Teixeira; Ferreira, Maria do Carmo

    2012-01-01

    This volume spans 10 chapters covering different aspects of transport phenomena including fixed and fluidized systems, spouted beds, electrochemical and wastewater treatment reactors. This e-book will be valuable for students, engineers and researchers aiming to keep updated on the latest developments on particulate systems.

  6. Discovery potential for new phenomena

    International Nuclear Information System (INIS)

    Godfrey, S.; Price, L.E.

    1997-03-01

    The authors examine the ability of future facilities to discover and interpret non-supersymmetric new phenomena. The authors first explore explicit manifestations of new physics, including extended gauge sectors, leptoquarks, exotic fermions, and technicolor models. They then take a more general approach where new physics only reveals itself through the existence of effective interactions at lower energy scales

  7. Strings, fields and critical phenomena

    International Nuclear Information System (INIS)

    Ambjoern, J.

    1987-07-01

    The connection between field theory and critical phenomena is reviewed. Emphasis is put on the use of Monte Carlo methods in the study of non-perturbative aspects of field theory. String theory is then described as a statistical theory of random surfaces and the critical behaviour is analyzed both by analytical and numerical methods. (orig.)

  8. System Shock: The Archetype of Operational Shock

    Science.gov (United States)

    2017-05-25

    the battle space. They can also facilitate a much greater understanding of the variables involved in each party’s decision - making process. However...system shock nests within current US Army Unified Land Operations doctrine. In order to test the utility of system shock theory to Gray Zone...23 Neil E. Harrison, “Thinking about the World We Make ” in Chaos Theory in the Social Sciences: Foundations and Applications

  9. Shock tubes and waves; Proceedings of the Sixteenth International Symposium, Rheinisch-Westfaelische Technische Hochschule, Aachen, Federal Republic of Germany, July 26-31, 1987

    Science.gov (United States)

    Groenig, Hans

    Topics discussed in this volume include shock wave structure, propagation, and interaction; shocks in condensed matter, dusty gases, and multiphase media; chemical processes and related combustion and detonation phenomena; shock wave reflection, diffraction, and focusing; computational fluid dynamic code development and shock wave application; blast and detonation waves; advanced shock tube technology and measuring technique; and shock wave applications. Papers are presented on dust explosions, the dynamics of shock waves in certain dense gases, studies of condensation kinetics behind incident shock waves, the autoignition mechanism of n-butane behind a reflected shock wave, and a numerical simulation of the focusing process of reflected shock waves. Attention is also given to the equilibrium shock tube flow of real gases, blast waves generated by planar detonations, modern diagnostic methods for high-speed flows, and interaction between induced waves and electric discharge in a very high repetition rate excimer laser.

  10. Admissibility region for rarefaction shock waves in dense gases

    NARCIS (Netherlands)

    Zamfirescu, C.; Guardone, A.; Colonna, P.

    2008-01-01

    In the vapour phase and close to the liquid–vapour saturation curve, fluids made of complex molecules are expected to exhibit a thermodynamic region in which the fundamental derivative of gasdynamic ? is negative. In this region, non-classical gasdynamic phenomena such as rarefaction shock waves are

  11. Multiple shocks, coping and welfare consequences: natural disasters and health shocks in the Indian Sundarbans.

    Science.gov (United States)

    Mazumdar, Sumit; Mazumdar, Papiya Guha; Kanjilal, Barun; Singh, Prashant Kumar

    2014-01-01

    Based on a household survey in Indian Sundarbans hit by tropical cyclone Aila in May 2009, this study tests for evidence and argues that health and climatic shocks are essentially linked forming a continuum and with exposure to a marginal one, coping mechanisms and welfare outcomes triggered in the response is significantly affected. The data for this study is based on a cross-sectional household survey carried out during June 2010. The survey was aimed to assess the impact of cyclone Aila on households and consequent coping mechanisms in three of the worst-affected blocks (a sub-district administrative unit), viz. Hingalganj, Gosaba and Patharpratima. The survey covered 809 individuals from 179 households, cross cutting age and gender. A separate module on health-seeking behaviour serves as the information source of health shocks defined as illness episodes (ambulatory or hospitalized) experienced by household members. Finding reveals that over half of the households (54%) consider that Aila has dealt a high, damaging impact on their household assets. Result further shows deterioration of health status in the period following the incidence of Aila. Finding suggests having suffered multiple shocks increases the number of adverse welfare outcomes by 55%. Whereas, suffering either from the climatic shock (33%) or the health shock (25%) alone increases such risks by a much lesser extent. The multiple-shock households face a significantly higher degree of difficulty to finance expenses arising out of health shocks, as opposed to their counterparts facing only the health shock. Further, these households are more likely to finance the expenses through informal loans and credit from acquaintances or moneylenders. This paper presented empirical evidence on how natural and health shocks mutually reinforce their resultant impact, making coping increasingly difficult and present significant risks of welfare loss, having short as well as long-run development manifestations.

  12. Nonlinear Weibel Instability and Turbulence in Strong Collisionless Shocks

    International Nuclear Information System (INIS)

    Medvedev, Mikhail M.

    2008-01-01

    This research project was devoted to studies of collisionless shocks, their properties, microphysics and plasma physics of underlying phenomena, such as Weibel instability and generation of small-scale fields at shocks, particle acceleration and transport in the generated random fields, radiation mechanisms from these fields in application to astrophysical phenomena and laboratory experiments (e.g., laser-plasma and beam-plasma interactions, the fast ignition and inertial confinement, etc.). Thus, this study is highly relevant to astrophysical sciences, the inertial confinement program and, in particular, the Fast Ignition concept, etc. It makes valuable contributions to the shock physics, nonlinear plasma theory, as well as to the basic plasma science, in general

  13. Transport phenomena in multiphase flows

    CERN Document Server

    Mauri, Roberto

    2015-01-01

    This textbook provides a thorough presentation of the phenomena related to the transport of mass, momentum and energy.  It lays all the basic physical principles, then for the more advanced readers, it offers an in-depth treatment with advanced mathematical derivations and ends with some useful applications of the models and equations in specific settings. The important idea behind the book is to unify all types of transport phenomena, describing them within a common framework in terms of cause and effect, respectively represented by the driving force and the flux of the transported quantity. The approach and presentation are original in that the book starts with a general description of transport processes, providing the macroscopic balance relations of fluid dynamics and heat and mass transfer, before diving into the mathematical realm of continuum mechanics to derive the microscopic governing equations at the microscopic level. The book is a modular teaching tool and can be used either for an introductory...

  14. A cross-country analysis of climate shocks and smallholder food insecurity.

    Directory of Open Access Journals (Sweden)

    Meredith T Niles

    Full Text Available Future climate changes will affect smallholder farmers in the developing world, posing threats to household food security. Nevertheless, there remains limited comparable evidence across multiple countries and regions regarding the global extent of climate shocks affecting smallholder food security. We examine data from 5,299 household surveys across 15 countries in Latin America, Africa and South Asia to assess the extent of climate shocks and their association with food insecurity, as well as what strategies may help buffer against climate shocks. We find that 71% of households reported experiencing a climate shock in the previous five years. Fifty-four percent reported experiencing food insecurity during one or more months annually. A multilevel statistical model estimated factors correlated with food insecurity as well as factors correlated with food insecurity among households that had experienced a climate shock. Households that reported experiencing a climate shock were 1.73 times more likely to be food insecure. As well, larger and poorer households were associated with higher odds of food insecurity while using pesticides, keeping large livestock, and being more educated are associated with lower odds of food insecurity. Among households that had experienced a climate shock, additional factors are correlated with lower odds of food insecurity when compared to otherwise similar households: use of fertilizers, pesticides, veterinary medicines, large livestock, and household assets. Together, these results demonstrate the extent of existing climate shocks affecting smallholder farmers and how interventions may potentially support adaptation and reduce food insecurity.

  15. A cross-country analysis of climate shocks and smallholder food insecurity.

    Science.gov (United States)

    Niles, Meredith T; Salerno, Jonathan D

    2018-01-01

    Future climate changes will affect smallholder farmers in the developing world, posing threats to household food security. Nevertheless, there remains limited comparable evidence across multiple countries and regions regarding the global extent of climate shocks affecting smallholder food security. We examine data from 5,299 household surveys across 15 countries in Latin America, Africa and South Asia to assess the extent of climate shocks and their association with food insecurity, as well as what strategies may help buffer against climate shocks. We find that 71% of households reported experiencing a climate shock in the previous five years. Fifty-four percent reported experiencing food insecurity during one or more months annually. A multilevel statistical model estimated factors correlated with food insecurity as well as factors correlated with food insecurity among households that had experienced a climate shock. Households that reported experiencing a climate shock were 1.73 times more likely to be food insecure. As well, larger and poorer households were associated with higher odds of food insecurity while using pesticides, keeping large livestock, and being more educated are associated with lower odds of food insecurity. Among households that had experienced a climate shock, additional factors are correlated with lower odds of food insecurity when compared to otherwise similar households: use of fertilizers, pesticides, veterinary medicines, large livestock, and household assets. Together, these results demonstrate the extent of existing climate shocks affecting smallholder farmers and how interventions may potentially support adaptation and reduce food insecurity.

  16. Numerical study of effects of accommodation coefficients on slip phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Jae; Kwon, Oh Joon [KAIST, Daejeon (Korea, Republic of)

    2015-05-15

    An unstructured mesh Navier-Stokes solver employing a Maxwell slip boundary condition was developed. The present flow solver was applied to the simulation of flows around an axisymmetric hollow cylinder in a Mach 10.4 free stream, known as Calspan-UB Research Center (CUBRC) Run 14 case, and the velocity slip and the temperature jump on the cylinder surface were investigated. The effect of tangential momentum and thermal accommodation coefficients used in the Maxwell condition was also investigated by adjusting their values. The results show that the reverse flow region is developed on the body surface due to the interaction between the shock and the boundary layer. Also, the shock impingement makes pressure high. The flow properties on the surface agree well with the experimental data, and the velocity slip and the temperature jump vary consistently with the local Knudsen number change. The accommodation coefficients affect the slip phenomena and the size of the flow region. The slip phenomena become larger when both tangential momentum and thermal accommodation coefficients are decreased. However, the range of the reverse flow region decreases when the momentum accommodation coefficient is decreased. The characteristics of the momentum and thermal accommodation coefficients also are overlapped when they are altered together.

  17. Mathematical Modeling of Diverse Phenomena

    Science.gov (United States)

    Howard, J. C.

    1979-01-01

    Tensor calculus is applied to the formulation of mathematical models of diverse phenomena. Aeronautics, fluid dynamics, and cosmology are among the areas of application. The feasibility of combining tensor methods and computer capability to formulate problems is demonstrated. The techniques described are an attempt to simplify the formulation of mathematical models by reducing the modeling process to a series of routine operations, which can be performed either manually or by computer.

  18. Multiparticle phenomena and Landau damping

    International Nuclear Information System (INIS)

    Talman, R.

    1987-01-01

    The purpose of this paper is to survey various methods of studying multiparticle phenomena in accelerators. Both experimental and theoretical methods are described. An effort has been made to emphasize the intuitive and qualitative aspects rather than the detailed mathematics. Some of the terms or concepts to be explained are coherent and incoherent tunes, normal modes, Landau damping, beam-transfer functions, and feedback. These are all of daily importance in the interpretation of colliding-beam observations and the control of performance

  19. "Did You Climax or Are You Just Laughing at Me?" Rare Phenomena Associated With Orgasm.

    Science.gov (United States)

    Reinert, Anna E; Simon, James A

    2017-07-01

    The study of the human orgasm has shown a core set of physiologic and psychological symptoms experienced by most individuals. The study of normal sheds light on the abnormal and has spotlighted rare physical and psychological symptoms experienced by some individuals in association with orgasm. These phenomena are rare and, as is typical of rare phenomena, their documentation in the medical literature is largely confined to case studies. To identify peri-orgasmic phenomena, defined as unusual physical or psychological symptoms subjectively experienced by some individuals as part of the orgasm response, distinct from the usual or normal orgasm response. A list of peri-orgasmic phenomena was made with help from sexual health colleagues and, using this list as a foundation, a literature search was performed of articles published in English. Publications included in this review report on physical or psychological phenomena at the time of orgasm that are distinct from psychological, whole-body, and genito-pelvic sensations commonly experienced at the time of orgasm. Cases of physical symptoms related to the physiology of sexual intercourse and not specifically to orgasm were excluded. Case studies of peri-orgasmic phenomena were reviewed, including cases describing cataplexy (weakness), crying, dysorgasmia, dysphoria, facial and/or ear pain, foot pain, headache, pruritus, laughter, panic attack, post-orgasm illness syndrome, seizures, and sneezing. The literature review confirms the existence of diverse and frequently replicated peri-orgasmic phenomena. The value of case studies is in the collection and recording of observations so that hypotheses can be formed about the observed phenomena. Accordingly, this review could inspire further research on the neurophysiologic mechanisms of orgasm. Reinert AE, Simon JA. "Did You Climax or Are You Just Laughing at Me?" Rare Phenomena Associated With Orgasm. Sex Med Rev 2017;5:275-281. Copyright © 2017 International Society for

  20. Evaluation of XHVRB for Capturing Explosive Shock Desensitization

    Science.gov (United States)

    Tuttle, Leah; Schmitt, Robert; Kittell, Dave; Harstad, Eric

    2017-06-01

    Explosive shock desensitization phenomena have been recognized for some time. It has been demonstrated that pressure-based reactive flow models do not adequately capture the basic nature of the explosive behavior. Historically, replacing the local pressure with a shock captured pressure has dramatically improved the numerical modeling approaches. Models based upon shock pressure or functions of entropy have recently been developed. A pseudo-entropy based formulation using the History Variable Reactive Burn model, as proposed by Starkenberg, was implemented into the Eulerian shock physics code CTH. Improvements in the shock capturing algorithm were made. The model is demonstrated to reproduce single shock behavior consistent with published pop plot data. It is also demonstrated to capture a desensitization effect based on available literature data, and to qualitatively capture dead zones from desensitization in 2D corner turning experiments. This models shows promise for use in modeling and simulation problems that are relevant to the desensitization phenomena. Issues are identified with the current implementation and future work is proposed for improving and expanding model capabilities. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. DOE's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  1. Antagonistic Phenomena in Network Dynamics

    Science.gov (United States)

    Motter, Adilson E.; Timme, Marc

    2018-03-01

    Recent research on the network modeling of complex systems has led to a convenient representation of numerous natural, social, and engineered systems that are now recognized as networks of interacting parts. Such systems can exhibit a wealth of phenomena that not only cannot be anticipated from merely examining their parts, as per the textbook definition of complexity, but also challenge intuition even when considered in the context of what is now known in network science. Here, we review the recent literature on two major classes of such phenomena that have far-reaching implications: (a) antagonistic responses to changes of states or parameters and (b) coexistence of seemingly incongruous behaviors or properties - both deriving from the collective and inherently decentralized nature of the dynamics. They include effects as diverse as negative compressibility in engineered materials, rescue interactions in biological networks, negative resistance in fluid networks, and the Braess paradox occurring across transport and supply networks. They also include remote synchronization, chimera states, and the converse of symmetry breaking in brain, power-grid, and oscillator networks as well as remote control in biological and bioinspired systems. By offering a unified view of these various scenarios, we suggest that they are representative of a yet broader class of unprecedented network phenomena that ought to be revealed and explained by future research.

  2. Experiencing sexuality after intestinal stoma

    Directory of Open Access Journals (Sweden)

    Maria Angela Boccara de Paula

    2012-06-01

    Full Text Available OBJECTIVE: Identify the Social Representations (SR of ostomized people in terms of sexuality after the stoma. METHODS: An exploratory, descriptive, qualitative study using the Social Representation Theory with 15 ostomized people (8 females, mean age of 57.9 years, between August and September 2005. Data obtained from transcribed interviews were submitted to content analysis, resulting in the thematic unit "Giving new meaning to sexuality" and subthemes. RESULTS: The study demonstrated that the intestinal stoma interferes in the sexuality experience, showing that the meanings attributed to this experience are based on individual life stories, quality of personal relationships established in practice and perception of sexuality, despite the stoma. CONCLUSIONS: The Social Representations, in terms of experiencing sexuality after the stoma, are based on meanings attributed to the body, associated with daily life and present in the social imaginary. It is influenced by other factors, such as physiological changes resulting from the surgery and the fact of having or not a partner. Care taken during sexual practices provide greater security and comfort in moments of intimacy, resembling the closest to what ostomized people experienced before the stoma. The self-irrigation technique associated or not with the use of artificial occluder, has been attested by its users as a positive element that makes a difference in sexual practice after the stoma. The support to ostomized people should be comprehensive, not limited to technical care and disease, which are important, but not sufficient. The interdisciplinary health team should consider all aspects of the person, seeking a real meeting between subjects.OBJETIVO: Identificar as Representações Sociais (RS da pessoa estomizada intestinal sobre vivência da sexualidade após confecção do estoma. MÉTODOS: Estudo exploratório, descritivo, qualitativo do ponto de vista do referencial da Representa

  3. Phantom shocks in patients with implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Berg, Selina Kikkenborg; Moons, Philip; Zwisler, Ann-Dorthe

    2013-01-01

    of phantom shocks.METHODS AND RESULTS: The design was secondary explorative analyses of data from a randomized controlled trial. One hundred and ninety-six patients with first-time ICD implantation (79% male, mean age 58 years) were randomized (1 : 1) to either combined rehabilitation or a control group...... questions regarding the experience of phantom shocks, date, time, and place. Twelve patients (9.4%) experienced a phantom shock, 7 in the intervention group and 5 in the control group (NS). Neither age, sex, quality of life nor perceived health at baseline was significantly related to the probability...

  4. Luminous Phenomena - A Scientific Investigation of Anomalous Luminous Atmospheric Phenomena

    Science.gov (United States)

    Teodorani, M.

    2003-12-01

    Anomalous atmospheric luminous phenomena reoccur in several locations of Earth, in the form of multi-color light balls characterized by large dimensions, erratic motion, long duration and a correlated electromagnetic field. The author (an astrophysicist) of this book, which is organized as a selection of some of his technical and popularizing papers and seminars, describes and discusses all the efforts that have been done in 10 years, through several missions and a massive data analysis, in order to obtain some scientific explanation of this kind of anomalies, in particular the Hessdalen anomaly in Norway. The following topics are treated in the book: a) geographic archive of the areas of Earth where such phenomena are known to reoccur most often; b) observational techniques of astrophysical kind that have been used to acquire the data; c) main scientific results obtained so far; d) physical interpretation and natural hypothesis vs. ETV hypothesis; e) historical and chronological issues; f) the importance to brindle new energy sources; g) the importance to keep distance from any kind of "ufology". An unpublished chapter is entirely devoted to a detailed scientific investigation project of light phenomena reoccurring on the Ontario lake; the chosen new-generation multi-wavelength sensing instrumentation that is planned to be used in future missions in that specific area, is described together with scientific rationale and planned procedures. The main results, which were obtained in other areas of the world, such as the Arizona desert, USA and the Sibillini Mountains, Italy, are also briefly mentioned. One chapter is entirely dedicated to the presentation of extensive abstracts of technical papers by the author concerning this specific subject. The book is accompanied with a rich source of bibliographic references.

  5. The effect of health shocks on smoking and obesity.

    Science.gov (United States)

    Sundmacher, Leonie

    2012-08-01

    To investigate whether negative changes in their own health (i.e. health shocks) or in that of a smoking or obese household member, lead smokers to quit smoking and obese individuals to lose weight. The study is informed by economic models ('rational addiction' and 'demand for health' models) which offer hypotheses on the relationship between health shocks and health-related behaviour. Each hypothesis was tested applying a discrete-time hazard model with random effects using up to ten waves of the German Socioeconomic Panel (GSOEP) and statistics on cigarette, food and beverage prices provided by the Federal Statistical Office. Health shocks had a significant positive impact on the probability that smokers quit during the same year in which they experienced the health shock. Health shocks of a smoking household member between year t-2 and t-1 also motivated smoking cessation, although statistical evidence for this was weaker. Health shocks experienced by obese individuals or their household members had, on the other hand, no significant effect on weight loss, as measured by changes in Body Mass Index (BMI). The results of the study suggest that smokers are aware of the risks associated with tobacco consumption, know about effective strategies to quit smoking, and are willing to quit for health-related reasons. In contrast, there was no evidence for changes in health-related behaviour among obese individuals after a health shock.

  6. Shock waves in P-bar target

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhijing; Anderson, K.

    1991-11-01

    The deposition of large amount of beam energy in short time will cause high temperature and pressure in the center of P-bar Target, and this disturbance will propagate outwards as a shock wave. Shock wave induced material changes which are of our concern include void growth and accompanying density decrease which will decrease antiproton yield, and crack formation and fracture as was observed in tungsten target which will destroy the integrity of the target. Our objective is to analyze the shock wave behavior in the target, optimize its design so that the destructive effects of shock wave can be minimized, the integrity of the target can be maintained, and a reasonably high yield of antiproton production can be achieved. In this report we put together some results of our analysis of a cylindrical copper target. We hope that it will provide a general overview of the shock wave phenomena in the target, establish a basis for further research, and facilitate the target design. First, energy deposition data are analyzed, and it is justified that as an approximation, the problem can be treated as axi-symmetric. The average data therefore are used as energy profile, however, the maximum energy deposition are still used as the peak value. Next some basic estimations are made as to what temperature and pressure can reach at present level of energy deposition. Then some characteristics of wave propagation in a thermal shock loaded solid are illustrated with a one-dimensional model. Since there is no analytical solution available for cylindrical geometry, our understanding of the problem relies on numerical model, which are performed via finite element package ANSYS. results of numerical analysis are summarized, sources of potential danger are identified, and design ideas to minimize the damage are proposed.

  7. Shock waves in P-bar target

    International Nuclear Information System (INIS)

    Tang, Zhijing; Anderson, K.

    1991-11-01

    The deposition of large amount of beam energy in short time will cause high temperature and pressure in the center of P-bar Target, and this disturbance will propagate outwards as a shock wave. Shock wave induced material changes which are of our concern include void growth and accompanying density decrease which will decrease antiproton yield, and crack formation and fracture as was observed in tungsten target which will destroy the integrity of the target. Our objective is to analyze the shock wave behavior in the target, optimize its design so that the destructive effects of shock wave can be minimized, the integrity of the target can be maintained, and a reasonably high yield of antiproton production can be achieved. In this report we put together some results of our analysis of a cylindrical copper target. We hope that it will provide a general overview of the shock wave phenomena in the target, establish a basis for further research, and facilitate the target design. First, energy deposition data are analyzed, and it is justified that as an approximation, the problem can be treated as axi-symmetric. The average data therefore are used as energy profile, however, the maximum energy deposition are still used as the peak value. Next some basic estimations are made as to what temperature and pressure can reach at present level of energy deposition. Then some characteristics of wave propagation in a thermal shock loaded solid are illustrated with a one-dimensional model. Since there is no analytical solution available for cylindrical geometry, our understanding of the problem relies on numerical model, which are performed via finite element package ANSYS. results of numerical analysis are summarized, sources of potential danger are identified, and design ideas to minimize the damage are proposed

  8. Radiating shocks and condensations in flares

    International Nuclear Information System (INIS)

    Fisher, G.H.

    1985-01-01

    Rapid energy release (by either ''thick target'' (beam) or ''thermal'' models of heating) in solar flare loop models usually leads to ''chromospheric evaporation,'' the process of heating cool chromospheric material to coronal temperatures, and the resulting increase in hot soft x-ray emitting plasma. The evaporated plasma flows up into the coronal portion of the loop because of the increased pressure in the evaporated region. However, the pressure increase also leads to a number of interesting phenomena in the flare chromosphere, which will be the subject of this paper. The sudden pressure increase in the evaporated plasma initiates a downward moving ''chromospheric condensation,'' an overdense region which gradually decelerates as it accretes material and propagates into the gravitationally stratified chromosphere. Solutions to an equation of motion for this condensation shows that its motion decays after about one minute of propagation into the chromosphere. When the front of this downflowing region is supersonic relative to the atmosphere ahead of it, a radiating shock will form. If the downflow is rapid enough, the shock strength should be sufficient to excite uv radiation normally associated with the transition region, and furthermore, the radiating shock will be brighter than the transition region. These results lead to a number of observationally testable relationships between the optical and ultraviolet spectra from the condensation and radiating shock

  9. Report of 22nd International Symposium on Shock Waves; Dai 22 kai kokusai shogekiha symposium shusseki hokoku

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, K. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science

    1999-11-05

    Outlined herein are the topics at the 22nd. International Symposium on Shock Waves, held in July 1999 in London. Prof. Takayama of Tohoku University gave an invited lecture on application of shock waves to medical area, stressing significance of shock waves on a human body. A total of 81 papers were presented from Japan. Number of Japanese papers and number of Japanese attendees both accounted for approximately 25%. The themes of these papers are centered by behavior of shock waves (e.g., propagation, reflection, and diffraction), extreme supersonic flows, interference between shock wave and boundary layer, aerodynamics (e.g., interference between vortex and shock wave), numerical simulation of shock wave phenomena, development of a new shock wave tube and measurement method, researches on elementary steps in chemical reactions, shock wave phenomena in condensed media and multi-phase media, shock wave noise produced while a high-speed train is running in a tunnel, and application of shock waves to industrial and medical areas. Japan contributes much to the application to medical area, and a method dispensing with injection is reported. Japan's aerospace-related researches include interference between shock wave and boundary layer, in which the real gas effect is taken into consideration, designs for protection from heat during the re-entry into the atmosphere, and construction of the world largest free-piston type wind tunnel. (NEDO)

  10. Hydraulic shock absorbers

    International Nuclear Information System (INIS)

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  11. Our Favorite Film Shocks

    DEFF Research Database (Denmark)

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  12. Climate shocks and conflict

    NARCIS (Netherlands)

    Papaioannou, Kostadis J.

    2016-01-01

    This paper offers a historical micro-level analysis of the impact of climate shocks on the incidence of civil conflict in colonial Nigeria (1912-1945). Primary historical sources on court cases, prisoners and homicides are used to capture conflict. To measure climate shocks we use the deviation

  13. High pressure multiple shock response of aluminum

    International Nuclear Information System (INIS)

    Lawrence, R.J.; Asay, J.R.

    1977-01-01

    It is well known that both dynamic yield strength and rate-dependent material response exert direct influence on the development of surface and interface instabilities under conditions of strong shock loading. A detailed understanding of these phenomena is therefore an important aspect of the analysis of dynamic inertial confinement techniques which are being used in such applications as the generation of controlled thermonuclear fusion. In these types of applications the surfaces and interfaces under consideration can be subjected to cyclic loading characterized by shock pressures on the order of 100 GPa or more. It thus becomes important to understand how rate effects and material strength differ from the values observed in the low pressure regime where they are usually measured, as well as how they are altered by the loading history

  14. Unusual behaviour of usual materials in shock waves

    International Nuclear Information System (INIS)

    Kanel, G I

    2014-01-01

    Exotic results of investigations of inelastic deformation and fracture under shock wave loading are presented and briefly discussed. Temperature effects on the flow stress at high strain rate may differ even in sign from those we observe at low and moderate strain rates. Investigations of the temperature-rate dependence of the yield stress at shock compression demonstrate intense multiplication of dislocations. At the highest strain rates, so-called ideal (ultimate) shear and tensile strength is reached in experiments with picosecond durations of shock loading. Although grain boundaries, in general, reduce resistance to fracture as compared to single crystals, the spall strength of ultra-fine-grained metals usually slightly exceeds that of coarse-grain samples. Failure wave phenomena have been observed in shock-compressed glasses.

  15. Correlated randomness and switching phenomena

    Science.gov (United States)

    Stanley, H. E.; Buldyrev, S. V.; Franzese, G.; Havlin, S.; Mallamace, F.; Kumar, P.; Plerou, V.; Preis, T.

    2010-08-01

    One challenge of biology, medicine, and economics is that the systems treated by these serious scientific disciplines have no perfect metronome in time and no perfect spatial architecture-crystalline or otherwise. Nonetheless, as if by magic, out of nothing but randomness one finds remarkably fine-tuned processes in time and remarkably fine-tuned structures in space. Further, many of these processes and structures have the remarkable feature of “switching” from one behavior to another as if by magic. The past century has, philosophically, been concerned with placing aside the human tendency to see the universe as a fine-tuned machine. Here we will address the challenge of uncovering how, through randomness (albeit, as we shall see, strongly correlated randomness), one can arrive at some of the many spatial and temporal patterns in biology, medicine, and economics and even begin to characterize the switching phenomena that enables a system to pass from one state to another. Inspired by principles developed by A. Nihat Berker and scores of other statistical physicists in recent years, we discuss some applications of correlated randomness to understand switching phenomena in various fields. Specifically, we present evidence from experiments and from computer simulations supporting the hypothesis that water’s anomalies are related to a switching point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell), and that the bubbles in economic phenomena that occur on all scales are not “outliers” (another Gladwell immortalization). Though more speculative, we support the idea of disease as arising from some kind of yet-to-be-understood complex switching phenomenon, by discussing data on selected examples, including heart disease and Alzheimer disease.

  16. Phenomena and Diosignes of Aratous

    Science.gov (United States)

    Avgoloupis, S. I.

    2013-01-01

    Aratous (305-240B.C.) was a singular intellectual, writer and poet which engage himself to compose a very interesting astronomical poet, using the "Dactylous sixstage' style, the formal style of the ancient Greek Epic poetry. This astronomic poem of Aratous "Phenomena and Diosignes" became very favorite reading during the Alexandrine, the Romman and the Byzandin eras as well and had received many praises from significant poets and particularly from Hipparchous and from Theonas from Alexandria, an astronomer of 4rth century A.C.(in Greeks)

  17. Phase transitions and critical phenomena

    CERN Document Server

    Domb, Cyril

    2001-01-01

    The field of phase transitions and critical phenomena continues to be active in research, producing a steady stream of interesting and fruitful results. It has moved into a central place in condensed matter studies.Statistical physics, and more specifically, the theory of transitions between states of matter, more or less defines what we know about 'everyday' matter and its transformations.The major aim of this serial is to provide review articles that can serve as standard references for research workers in the field, and for graduate students and others wishing to obtain reliable in

  18. Phase transitions and critical phenomena

    CERN Document Server

    Domb, Cyril

    2000-01-01

    The field of phase transitions and critical phenomena continues to be active in research, producing a steady stream of interesting and fruitful results. No longer an area of specialist interest, it has acquired a central focus in condensed matter studies. The major aim of this serial is to provide review articles that can serve as standard references for research workers in the field, and for graduate students and others wishing to obtain reliable information on important recent developments.The two review articles in this volume complement each other in a remarkable way. Both deal with what m

  19. Nonlinear phenomena in general relativity

    Science.gov (United States)

    Allahyari, Alireza; Firouzjaee, Javad T.; Mansouri, Reza

    2018-04-01

    The perturbation theory plays an important role in studying structure formation in cosmology and post-Newtonian physics, but not all phenomena can be described by the linear perturbation theory. Thus, it is necessary to study exact solutions or higher-order perturbations. Specifically, we study black hole (apparent) horizons and the cosmological event horizon formation in the perturbation theory. We emphasize that in the perturbative regime of the gravitational potential these horizons cannot form in the lower order. Studying the infinite plane metric, we show that, to capture the cosmological constant effect, we need at least a second-order expansion.

  20. Nonlinear phenomena at cyclotron resonance

    International Nuclear Information System (INIS)

    Subbarao, D.; Uma, R.

    1986-01-01

    Finite amplitude electromagnetic waves in a magnetoplasma which typically occur in situations as in present day wave heating, current drives and other schemes in magnetically confined fusion systems, can show qualitatively different absorption and emission characteristics around resonant frequencies of the plasma because of anharmonicity. Linear wave plasma coupling as well as weak nonlinear effects such as parametric instabilities generally overlook this important effect even though the thresholds for the two phenomena as shown here are comparable. Though the effects described here are relevant to a host of nonlinear resonance effects in fusion plasmas, the authors mainly limit themselves to ECRH

  1. Violent phenomena in the Universe

    CERN Document Server

    Narlikar, Jayant V

    2007-01-01

    The serenity of a clear night sky belies the evidence-gathered by balloons, rockets, satellites, and telescopes-that the universe contains centers of furious activity that pour out vast amounts of energy, some in regular cycles and some in gigantic bursts. This reader-friendly book, acclaimed by Nature as ""excellent and uncompromising,"" traces the development of modern astrophysics and its explanations of these startling celestial fireworks.This lively narrative ranges from the gravitational theories of Newton and Einstein to recent exciting discoveries of such violent phenomena as supernova

  2. Nonlinear Dynamic Phenomena in Mechanics

    CERN Document Server

    Warminski, Jerzy; Cartmell, Matthew P

    2012-01-01

    Nonlinear phenomena should play a crucial role in the design and control of engineering systems and structures as they can drastically change the prevailing dynamical responses. This book covers theoretical and applications-based problems of nonlinear dynamics concerned with both discrete and continuous systems of interest in civil and mechanical engineering. They include pendulum-like systems, slender footbridges, shape memory alloys, sagged elastic cables and non-smooth problems. Pendulums can be used as a dynamic absorber mounted in high buildings, bridges or chimneys. Geometrical nonlinear

  3. Quantum theory of collective phenomena

    CERN Document Server

    Sewell, G L

    2014-01-01

    ""An excellent and competent introduction to the field … [and] … a source of information for the expert."" - Physics Today""This a book of major importance…. I trust that this book will be used as a basis for the teaching of a balanced, modern and rigorous course on statistical mechanics in all universities."" - Bulletin of the London Mathematical Society""This is one of the best introductions to the subject, and it is strongly recommended to anyone interested in collective phenomena."" - Physics Bulletin ""The book may be recommended for students as a well-balanced introduction to this rich s

  4. Foot anthropometry and morphology phenomena.

    Science.gov (United States)

    Agić, Ante; Nikolić, Vasilije; Mijović, Budimir

    2006-12-01

    Foot structure description is important for many reasons. The foot anthropometric morphology phenomena are analyzed together with hidden biomechanical functionality in order to fully characterize foot structure and function. For younger Croatian population the scatter data of the individual foot variables were interpolated by multivariate statistics. Foot structure descriptors are influenced by many factors, as a style of life, race, climate, and things of the great importance in human society. Dominant descriptors are determined by principal component analysis. Some practical recommendation and conclusion for medical, sportswear and footwear practice are highlighted.

  5. Gravitational Anomaly and Transport Phenomena

    International Nuclear Information System (INIS)

    Landsteiner, Karl; Megias, Eugenio; Pena-Benitez, Francisco

    2011-01-01

    Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.

  6. Quantum phenomena in gravitational field

    Science.gov (United States)

    Bourdel, Th.; Doser, M.; Ernest, A. D.; Voronin, A. Yu.; Voronin, V. V.

    2011-10-01

    The subjects presented here are very different. Their common feature is that they all involve quantum phenomena in a gravitational field: gravitational quantum states of ultracold antihydrogen above a material surface and measuring a gravitational interaction of antihydrogen in AEGIS, a quantum trampoline for ultracold atoms, and a hypothesis on naturally occurring gravitational quantum states, an Eötvös-type experiment with cold neutrons and others. Considering them together, however, we could learn that they have many common points both in physics and in methodology.

  7. Quantum phenomena in gravitational field

    International Nuclear Information System (INIS)

    Bourdel, Th.; Doser, M.; Ernest, A.D.; Voronin, A.Y.; Voronin, V.V.

    2010-01-01

    The subjects presented here are very different. Their common feature is that they all involve quantum phenomena in a gravitational field: gravitational quantum states of ultracold anti-hydrogen above a material surface and measuring a gravitational interaction of anti-hydrogen in AEGIS, a quantum trampoline for ultracold atoms, and a hypothesis on naturally occurring gravitational quantum states, an Eoetvoes-type experiment with cold neutrons and others. Considering them together, however, we could learn that they have many common points both in physics and in methodology. (authors)

  8. Shock - A reappraisal: The holistic approach

    Directory of Open Access Journals (Sweden)

    Fabrizio Giuseppe Bonanno

    2012-01-01

    Full Text Available Shock as reaction to life-threatening condition needs to be reclassified in a timely and more scientific synopsis. It is not possible or beneficial any longer to avoid a holistic approach in critical illness. Semantics of critical illness has often been unfriendly in the literature and a simplification with the elimination of conceptual pleonasms and misnomers under the exclusive light of physiology and physiopathology would be advantageous. Speaking one language to describe the same phenomenon worldwide is essential for understanding; moreover, it increases focus on characterization and significance of the phenomena.

  9. Phenomena identification and ranking tables (PIRT) for LBLOCA

    International Nuclear Information System (INIS)

    Shaw, R.A.; Dimenna, R.A.; Larson, T.K.; Wilson, G.E.

    1988-01-01

    The US Nuclear Regulatory Commission is sponsoring a program to provide validated reactor safety computer codes with quantified uncertainties. The intent is to quantify the accuracy of the codes for use in best estimate licensing applications. One of the tasks required to complete this program involves the identification and ranking of thermal-hydraulic phenomena that occur during particular accidents. This paper provides detailed tables of phenomena and importance ranks for a PWR LBLOCA. The phenomena were identified and ranked according to perceived impact on peak cladding temperature. Two approaches were used to complete this task. First, a panel of experts identified the physical processes considered to be most important during LBLOCA. A second team of experienced analysts then, in parallel, assembled complete tables of all plausible LBLOCA phenomena, regardless of perceived importance. Each phenomenon was then ranked in importance against every other phenomenon associated with a given component. The results were placed in matrix format and solved for the principal eigenvector. The results as determined by each method are presented in this report

  10. Measuring the Shock Stage of Asteroid Regolith Grains by Electron Back-Scattered Diffraction

    Science.gov (United States)

    Zolensky, Michael; Martinez, James; Sitzman, Scott; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Terada, Yasuko; Yagi, Naoto; Komatsu, Mutsumi; Ozawa, Hikaru; hide

    2018-01-01

    We have been analyzing Itokawa samples in order to definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by electron and X-ray diffraction. These techniques would then be available for samples returned from other asteroid regoliths.

  11. Natural phenomena hazards, Hanford Site, Washington

    International Nuclear Information System (INIS)

    Conrads, T.J.

    1998-01-01

    This document presents the natural phenomena hazard loads for use in implementing DOE Order 5480.28, Natural Phenomena Hazards Mitigation, and supports development of double-shell tank systems specifications at the Hanford Site in south-central Washington State. The natural phenomena covered are seismic, flood, wind, volcanic ash, lightning, snow, temperature, solar radiation, suspended sediment, and relative humidity

  12. Collisionless shock waves

    International Nuclear Information System (INIS)

    Sagdeev, R.Z.; Kennel, C.F.

    1991-01-01

    Collisionless shocks cannot occur naturally on the earth, because nearly all matter here consists of electrically neutral atoms and molecules. In space, however, high temperatures and ultraviolet radiation from hot stars decompose atoms into their constituent nuclei and electrons, producing a soup of electrically charged particles known as a plasma. Plasma physicists proposed that the collective electrical and magnetic properties of plasmas could produce interactions that take the place of collisions and permit shocks to form. In 1964 the theoretical work found its first experimental confirmation. Norman F. Ness and his colleagues at the Goddard Space Flight Center, using data collected from the iMP-1 spacecraft, detected clear signs that a collisionless shock exists where the solar wind encounters the earth's magnetic field. More recent research has demonstrated that collisionless shocks appear in a dazzling array of astronomical settings. For example, shocks have been found in the solar wind upstream (sunward) of all the planet and comets that have been visited by spacecraft. Violent flares on the sun generate shocks that propagate to the far reaches of the solar system; tremendous galactic outbursts create disruptions in the intergalactic medium that are trillions of times larger. In addition, many astrophysicists think that shocks from supernova explosions in our galaxy accelerate cosmic rays, a class of extraordinarily energetic elementary particles and atomic nuclei that rain down on the earth from all directions

  13. Pediatric Toxic Shock Syndrome

    Directory of Open Access Journals (Sweden)

    Jennifer Yee

    2017-09-01

    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the diagnosis and management of a pediatric patient with toxic shock syndrome. The case is also appropriate for teaching of medical students and advanced practice providers, as well as a review of the principles of crisis resource management, teamwork, and communication. Introduction: Toxic shock syndrome is a low-frequency, high-acuity scenario requiring timely identification and aggressive management. If patients suffering from this condition are managed incorrectly, they may progress into multi-organ dysfunction and potentially death. Toxic shock syndrome has been associated with Streptococcus and Staphylococcus aureus (Staph. Approximately half of Staph cases are associated with menstruation, which was first described in the 1970s-1980s and was associated with the use of absorbent tampons.1 Group A Streptococcus may cause complications such as necrotizing fasciitis and gangrenous myositis.2 Pediatric patients may present critically ill from toxic shock syndrome. Providers need to perform a thorough history and physical exam to discern the source of infection. Management requires aggressive care with antibiotics and IV fluids. Objectives: By the end of this simulation session, the learner will be able to: 1 Recognize toxic shock syndrome. 2 Review the importance of a thorough physical exam. 3 Discuss management of toxic shock syndrome, including supportive care and the difference in antibiotic choices for streptococcal and staphylococcal toxic shock syndrome. 4 Appropriately disposition a patient suffering from toxic shock syndrome. 5 Communicate effectively with team members and nursing staff during a resuscitation of a critically ill patient. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on toxic shock syndrome.

  14. Shocks near Jamming

    Science.gov (United States)

    Gómez, Leopoldo R.; Turner, Ari M.; van Hecke, Martin; Vitelli, Vincenzo

    2012-02-01

    Nonlinear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed and demonstrate that the elementary excitations are strongly nonlinear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.

  15. Mechanical shock absorber

    International Nuclear Information System (INIS)

    Vrillon, Bernard.

    1973-01-01

    The mechanical shock absorber described is made of a constant thickness plate pierced with circular holes regularly distributed in such a manner that for all the directions along which the strain is applied during the shock, the same section of the substance forming the plate is achieved. The shock absorber is made in a metal standing up to extensive deformation before breaking, selected from a group comprising mild steels and austenitic stainless steels. This apparatus is used for handling pots of fast neutron reactor fuel elements [fr

  16. Shock formation of HCO+

    International Nuclear Information System (INIS)

    Elitzur, M.

    1983-01-01

    It is shown that shocks propagating in dense molecular regions will lead to a decrease in HCO + relative abundance, in agreement with previous results by Iglesias and Silk. The shock enhancement of HCO + detected in the supernova remnant IC 443 by Dickenson et al. is due to enhanced ionization in the shocked material. This is the result of the material penetrating the remnant cavity where it becomes exposed to the trapped cosmic rays. A similar enhancement appears to have been detected by Wootten in W28 and is explained by the same model

  17. Earthquake prediction with electromagnetic phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Masashi, E-mail: hayakawa@hi-seismo-em.jp [Hayakawa Institute of Seismo Electomagnetics, Co. Ltd., University of Electro-Communications (UEC) Incubation Center, 1-5-1 Chofugaoka, Chofu Tokyo, 182-8585 (Japan); Advanced Wireless & Communications Research Center, UEC, Chofu Tokyo (Japan); Earthquake Analysis Laboratory, Information Systems Inc., 4-8-15, Minami-aoyama, Minato-ku, Tokyo, 107-0062 (Japan); Fuji Security Systems. Co. Ltd., Iwato-cho 1, Shinjyuku-ku, Tokyo (Japan)

    2016-02-01

    Short-term earthquake (EQ) prediction is defined as prospective prediction with the time scale of about one week, which is considered to be one of the most important and urgent topics for the human beings. If this short-term prediction is realized, casualty will be drastically reduced. Unlike the conventional seismic measurement, we proposed the use of electromagnetic phenomena as precursors to EQs in the prediction, and an extensive amount of progress has been achieved in the field of seismo-electromagnetics during the last two decades. This paper deals with the review on this short-term EQ prediction, including the impossibility myth of EQs prediction by seismometers, the reason why we are interested in electromagnetics, the history of seismo-electromagnetics, the ionospheric perturbation as the most promising candidate of EQ prediction, then the future of EQ predictology from two standpoints of a practical science and a pure science, and finally a brief summary.

  18. Research in magnetospheric wave phenomena

    International Nuclear Information System (INIS)

    Barfield, J.N.

    1975-01-01

    During the last 4 years a number of developments have occurred which have led to an increased understanding of the role of wave phenomena in the physical processes of the magnetosphere. While the studies span the frequency regime from millihertz to the electron gyrofrequency, the developments to be discussed in this paper have in common that they have added substantially to the understanding of the controlling processes, regions, and boundaries in the magnetosphere. The topics discussed are the increased awareness and documentation of the role of the plasmapause in micropulsation generation and propagation; the establishment of the role of ion cyclotron waves in the wave-particle interactions at the plasmapause; the discovery of magnetospheric electrostatic waves with ω = (3/2)Ω/sub -/; the discovery and preliminary identification of the source of plasmaspheric hiss; and the analysis of storm time Pc 5 waves as observed on the satellites ATS 1 and Explorer 45. (auth)

  19. Emergent Phenomena at Oxide Interfaces

    International Nuclear Information System (INIS)

    Hwang, H.Y.

    2012-01-01

    Transition metal oxides (TMOs) are an ideal arena for the study of electronic correlations because the s-electrons of the transition metal ions are removed and transferred to oxygen ions, and hence the strongly correlated d-electrons determine their physical properties such as electrical transport, magnetism, optical response, thermal conductivity, and superconductivity. These electron correlations prohibit the double occupancy of metal sites and induce a local entanglement of charge, spin, and orbital degrees of freedom. This gives rise to a variety of phenomena, e.g., Mott insulators, various charge/spin/orbital orderings, metal-insulator transitions, multiferroics, and superconductivity. In recent years, there has been a burst of activity to manipulate these phenomena, as well as create new ones, using oxide heterostructures. Most fundamental to understanding the physical properties of TMOs is the concept of symmetry of the order parameter. As Landau recognized, the essence of phase transitions is the change of the symmetry. For example, ferromagnetic ordering breaks the rotational symmetry in spin space, i.e., the ordered phase has lower symmetry than the Hamiltonian of the system. There are three most important symmetries to be considered here. (i) Spatial inversion (I), defined as r → -r. In the case of an insulator, breaking this symmetry can lead to spontaneous electric polarization, i.e. ferroelectricity, or pyroelectricity once the point group belongs to polar group symmetry. (ii) Time-reversal symmetry (T) defined as t → -t. In quantum mechanics, the time-evolution of the wave-function Ψ is given by the phase factor e -iEt/h b ar with E being the energy, and hence time-reversal basically corresponds to taking the complex conjugate of the wave-function. Also the spin, which is induced by the 'spinning' of the particle, is reversed by time-reversal. Broken T-symmetry is most naturally associated with magnetism, since the spin operator changes sign

  20. Transport phenomena in porous media

    CERN Document Server

    Ingham, Derek B

    1998-01-01

    Research into thermal convection in porous media has substantially increased during recent years due to its numerous practical applications. These problems have attracted the attention of industrialists, engineers and scientists from many very diversified disciplines, such as applied mathematics, chemical, civil, environmental, mechanical and nuclear engineering, geothermal physics and food science. Thus, there is a wealth of information now available on convective processes in porous media and it is therefore appropriate and timely to undertake a new critical evaluation of this contemporary information. Transport Phenomena in Porous Media contains 17 chapters and represents the collective work of 27 of the world's leading experts, from 12 countries, in heat transfer in porous media. The recent intensive research in this area has substantially raised the expectations for numerous new practical applications and this makes the book a most timely addition to the existing literature. It includes recent major deve...

  1. Electrostatic Phenomena on Planetary Surfaces

    Science.gov (United States)

    Calle, Carlos I.

    2017-02-01

    The diverse planetary environments in the solar system react in somewhat different ways to the encompassing influence of the Sun. These different interactions define the electrostatic phenomena that take place on and near planetary surfaces. The desire to understand the electrostatic environments of planetary surfaces goes beyond scientific inquiry. These environments have enormous implications for both human and robotic exploration of the solar system. This book describes in some detail what is known about the electrostatic environment of the solar system from early and current experiments on Earth as well as what is being learned from the instrumentation on the space exploration missions (NASA, European Space Agency, and the Japanese Space Agency) of the last few decades. It begins with a brief review of the basic principles of electrostatics.

  2. The quest for new phenomena

    International Nuclear Information System (INIS)

    Hinchliffe, I.

    1996-12-01

    The Standard Model of particle physics has been very successful in describing experimental data with great precision. With the exception of some neutrino anomalies, there is no data that is in disagreement with it. Nevertheless, the model is regarded as incomplete and unsatisfactory. There is no explanation of the pattern of quark and lepton masses and, possibly more important, no understanding of the scale of electroweak interactions. Electroweak symmetry breaking is implemented in the Standard Model from the presence of a scalar electroweak doublet, the Higgs field, that acquires a vacuum expectation value of order 250 GeV and leaves as a remnant one physical state, the electrically neutral Higgs boson whose mass is not predicted. In this talk, the author compares the techniques used at, and capabilities of, various facilities in searching for new phenomena. The author emphasizes the cases where information from more than one facility may be needed to fully explore the physics

  3. In-vessel phenomena -- CORA

    International Nuclear Information System (INIS)

    Ott, L.J.; Rij, W.I. van.

    1991-01-01

    Experiment-specific models have been employed since 1986 by Oak Ridge National Laboratory (ORNL) severe accident analysis programs for the purpose of boiling water reactor experimental planning and optimum interpretation of experimental results. The large integral tests performed to date, which start from an initial undamaged core state, have involved significantly different-from-prototypic boundary and experimental conditions because of either normal facility limitations or specific experimental constraints. These experiments (ACRR: DF-4, NRU: FLHT-6, and CORA) were designed to obtain specific phenomenological information such as the degradation and interaction of prototypic components and the effects on melt progression of control-blade materials and channel boxes. Applications of ORNL models specific to the KfK CORA-16 and CORA-17 experiments are discussed and significant findings from the experimental analyses such as the following are presented: applicability of available Zircaloy oxidation kinetics correlations; influence of cladding strain on Zircaloy oxidation; influence of spacer grids on the structural heatup; and the impact of treating the gaseous coolant as a gray interacting medium. The experiment-specific models supplement and support the systems-level accident analysis codes. They allow the analyst to accurately quantify the observed experimental phenomena and to compensate for the effect of known uncertainties. They provide a basis for the efficient development of new models for phenomena that are currently not modeled (such as material interactions). They can provide validated phenomenological models (from the results of the experiments) as candidates for incorporation in the systems-level ''whole-core'' codes

  4. Shock Isolation Elements Testing for High Input Loadings. Volume II. Foam Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*EXPANDED PLASTICS, (*SHOCK(MECHANICS), REDUCTION), TEST METHODS, SHOCK WAVES, STRAIN(MECHANICS), LOADS(FORCES), MATHEMATICAL MODELS, NUCLEAR EXPLOSIONS, HARDENING.

  5. Remote sensing of natural phenomena

    Directory of Open Access Journals (Sweden)

    Miodrag D. Regodić

    2014-06-01

    Full Text Available There has always been a need to directly perceive and study the events whose extent is beyond people's possibilities. In order to get new data and to make observations and studying much more objective in comparison with past syntheses - a new method of examination called remote sensing has been adopted. The paper deals with the principles and elements of remote sensing, as well as with the basic aspects of using remote research in examining meteorological (weather parameters and the conditions of the atmosphere. The usage of satellite images is possible in all phases of the global and systematic research of different natural phenomena when airplane and satellite images of different characteristics are used and their analysis and interpretation is carried out by viewing and computer added procedures. Introduction Remote sensing of the Earth enables observing and studying global and local events that occur on it. Satellite images are nowadays used in geology, agriculture, forestry, geodesy, meteorology, spatial and urbanism planning, designing of infrastructure and other objects, protection from natural and technological catastrophes, etc. It it possible to use satellite images in all phases of global and systematic research of different natural phenomena. Basics of remote sensing Remote sensing is a method of the acquisition and interpretation of information about remote objects without making a physical contact with them. The term Daljinska detekcija is a literal translation of the English term Remote Sensing. In French it isTeledetection, in German - Fernerkundung, in Russian - дистанционие иследования. We also use terms such as: remote survailance, remote research, teledetection, remote methods, and distance research. The basic elements included in Remote Sensing are: object, electromagnetic energy, sensor, platform, image, analysis, interpretation and the information (data, fact. Usage of satellite remote research in

  6. Shocks, singularities and oscillations in nonlinear optics and fluid mechanics

    CERN Document Server

    Santo, Daniele; Lannes, David

    2017-01-01

    The book collects the most relevant results from the INdAM Workshop "Shocks, Singularities and Oscillations in Nonlinear Optics and Fluid Mechanics" held in Rome, September 14-18, 2015. The contributions discuss recent major advances in the study of nonlinear hyperbolic systems, addressing general theoretical issues such as symmetrizability, singularities, low regularity or dispersive perturbations. It also investigates several physical phenomena where such systems are relevant, such as nonlinear optics, shock theory (stability, relaxation) and fluid mechanics (boundary layers, water waves, Euler equations, geophysical flows, etc.). It is a valuable resource for researchers in these fields. .

  7. The importance of microjet vs shock wave formation in sonophoresis.

    Science.gov (United States)

    Wolloch, Lior; Kost, Joseph

    2010-12-01

    Low-frequency ultrasound application has been shown to greatly enhance transdermal drug delivery. Skin exposed to ultrasound is affected in a heterogeneous manner, thus mass transport through the stratum corneum occurs mainly through highly permeable localized transport regions (LTRs). Shock waves and microjets generated during inertial cavitations are responsible for the transdermal permeability enhancement. In this study, we evaluated the effect of these two phenomena using direct and indirect methods, and demonstrated that the contribution of microjets to skin permeability enhancement is significantly higher than shock waves. Copyright © 2010. Published by Elsevier B.V.

  8. Have shock waves been observed in nuclear collisions

    International Nuclear Information System (INIS)

    Gudima, K.K.; Toneev, V.D.

    Experimental data on shock wave phenomena in nuclear reactions are analyzed within the kinetic theory rather than that of the hydrodynamic approach. Beginning with a presentation of the model, which is a generalization of the cascade--evaporation model to the case of the interaction of two nuclei, it is then ascertained to what degree the developed approach is valid. Next on the basis of this model the results of experiments performed are examined to find the effects of a shock wave. The results of this analysis and the related set-up of new experiments are discussed also. 34 references

  9. Counseling For Future Shock

    Science.gov (United States)

    Morgan, Lewis B.

    1974-01-01

    In this article the author looks at some of the searing prophecies made by Alvin Toffler in his book Future Shock and relates them to the world of the professional counselor and the clientele the counselor attempts to serve. (Author)

  10. Life shocks and homelessness.

    Science.gov (United States)

    Curtis, Marah A; Corman, Hope; Noonan, Kelly; Reichman, Nancy E

    2013-12-01

    We exploited an exogenous health shock-namely, the birth of a child with a severe health condition-to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide.

  11. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  12. Modeling of Particle Acceleration at Multiple Shocks Via Diffusive Shock Acceleration: Preliminary Results

    Science.gov (United States)

    Parker, L. N.; Zank, G. P.

    2013-12-01

    Successful forecasting of energetic particle events in space weather models require algorithms for correctly predicting the spectrum of ions accelerated from a background population of charged particles. We present preliminary results from a model that diffusively accelerates particles at multiple shocks. Our basic approach is related to box models (Protheroe and Stanev, 1998; Moraal and Axford, 1983; Ball and Kirk, 1992; Drury et al., 1999) in which a distribution of particles is diffusively accelerated inside the box while simultaneously experiencing decompression through adiabatic expansion and losses from the convection and diffusion of particles outside the box (Melrose and Pope, 1993; Zank et al., 2000). We adiabatically decompress the accelerated particle distribution between each shock by either the method explored in Melrose and Pope (1993) and Pope and Melrose (1994) or by the approach set forth in Zank et al. (2000) where we solve the transport equation by a method analogous to operator splitting. The second method incorporates the additional loss terms of convection and diffusion and allows for the use of a variable time between shocks. We use a maximum injection energy (Emax) appropriate for quasi-parallel and quasi-perpendicular shocks (Zank et al., 2000, 2006; Dosch and Shalchi, 2010) and provide a preliminary application of the diffusive acceleration of particles by multiple shocks with frequencies appropriate for solar maximum (i.e., a non-Markovian process).

  13. Technology shocks matter

    OpenAIRE

    Jonas D. M. Fisher

    2002-01-01

    This paper uses the neoclassical growth model to identify the effects of technological change on the US business cycle. In the model there are two sources of technological change: neutral, which effects the production of all goods homogeneously, and investment-specific. Investment-specific shocks are the unique source of the secular trend in the real price of investment goods, while shocks to both kinds of technology are the only factors which affect labor productivity in the long run. Consis...

  14. Magnetotail phenomena and auroral acceleration

    International Nuclear Information System (INIS)

    Giles, M.J.

    1980-01-01

    It is suggested that localised electrostatic potential wells could be generated in the plasma sheet by large amplitude electrostatic ion cyclotron waves. It is shown from a consideration of a simple one dimensional model that such wells could possess a double structure of oppositely directed fields elongated in longitude. The possibility that the waves could evolve from a turbulent ion wave cascade driven by Earthward streaming protons is discussed and the magnitude of the potentials that could be established in this way is estimated using results for condensed state turbulent equilibria. The projections of these wells along the highly conducting geomagnetic field lines form potential valleys across the field lines in the high latitude auroral plasma. It is shown that these valleys would be of the scale and depth needed to establish electrostatic shocks which would be of sufficient intensity to accelerate electrons to energies comparable to those observed in 'inverted-V' events. Potential wells are formed predominantly in the midnight sector of the plasma sheet and propagate Earthwards. This implies a corresponding equatorwards motion of the valley which, typically, would have a velocity of a few hundred m s -1 . (author)

  15. The Heliospheric Termination Shock

    Science.gov (United States)

    Jokipii, J. R.

    2013-06-01

    The heliospheric termination shock is a vast, spheroidal shock wave marking the transition from the supersonic solar wind to the slower flow in the heliosheath, in response to the pressure of the interstellar medium. It is one of the most-important boundaries in the outer heliosphere. It affects energetic particles strongly and for this reason is a significant factor in the effects of the Sun on Galactic cosmic rays. This paper summarizes the general properties and overall large-scale structure and motions of the termination shock. Observations over the past several years, both in situ and remote, have dramatically revised our understanding of the shock. The consensus now is that the shock is quite blunt, is with the front, blunt side canted at an angle to the flow direction of the local interstellar plasma relative to the Sun, and is dynamical and turbulent. Much of this new understanding has come from remote observations of energetic charged particles interacting with the shock, radio waves and radiation backscattered from interstellar neutral atoms. The observations and the implications are discussed.

  16. Polar Coordinate Lattice Boltzmann Kinetic Modeling of Detonation Phenomena

    International Nuclear Information System (INIS)

    Lin Chuan-Dong; Li Ying-Jun; Xu Ai-Guo; Zhang Guang-Cai

    2014-01-01

    A novel polar coordinate lattice Boltzmann kinetic model for detonation phenomena is presented and applied to investigate typical implosion and explosion processes. In this model, the change of discrete distribution function due to local chemical reaction is dynamically coupled into the modified lattice Boltzmann equation which could recover the Navier—Stokes equations, including contribution of chemical reaction, via the Chapman—Enskog expansion. For the numerical investigations, the main focuses are the nonequilibrium behaviors in these processes. The system at the disc center is always in its thermodynamic equilibrium in the highly symmetric case. The internal kinetic energies in different degrees of freedom around the detonation front do not coincide. The dependence of the reaction rate on the pressure, influences of the shock strength and reaction rate on the departure amplitude of the system from its local thermodynamic equilibrium are probed. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  17. Back to Bentham? Explorations of Experienced Utility

    NARCIS (Netherlands)

    D. Kahneman (Daniel); P.P. Wakker (Peter); R.K. Sarin (Rakesh)

    1997-01-01

    textabstractTwo core meanings of “utility” are distinguished. “Decision utility” is the weight of an outcome in a decision. “Experienced utility” is hedonic quality, as in Bentham’s usage. Experienced utility can be reported in real time (instant utility), or in retrospective evaluations of past

  18. Experienced discrimination amongst European old citizens

    NARCIS (Netherlands)

    van den Heuvel, Wim J. A.; van Santvoort, Marc M.

    2011-01-01

    This study analyses the experienced age discrimination of old European citizens and the factors related to this discrimination. Differences in experienced discrimination between old citizens of different European countries are explored. Data from the 2008 ESS survey are used. Old age is defined as

  19. Experienced General Music Teachers' Instructional Decision Making

    Science.gov (United States)

    Johnson, Daniel C.; Matthews, Wendy K.

    2017-01-01

    The purpose of this descriptive study was to explore experienced general music teachers' decision-making processes. Participants included seven experienced, American general music teachers who contributed their views during two phases of data collection: (1) responses to three classroom scenarios; and (2) in-depth, semi-structured, follow-up…

  20. EDITORIAL: Quantum phenomena in Nanotechnology Quantum phenomena in Nanotechnology

    Science.gov (United States)

    Loss, Daniel

    2009-10-01

    Twenty years ago the Institute of Physics launched the journal Nanotechnology from its publishing house based in the home town of Paul Dirac, a legendary figure in the development of quantum mechanics at the turn of the last century. At the beginning of the 20th century, the adoption of quantum mechanical descriptions of events transformed the existing deterministic world view. But in many ways it also revolutionised the progress of research itself. For the first time since the 17th century when Francis Bacon established inductive reasoning as the means of advancing science from fact to axiom to law, theory was progressing ahead of experiments instead of providing explanations for observations that had already been made. Dirac's postulation of antimatter through purely theoretical investigation before its observation is the archetypal example of theory leading the way for experiment. The progress of nanotechnology and the development of tools and techniques that enabled the investigation of systems at the nanoscale brought with them many fascinating observations of phenomena that could only be explained through quantum mechanics, first theoretically deduced decades previously. At the nanoscale, quantum confinement effects dominate the electrical and optical properties of systems. They also render new opportunities for manipulating the response of systems. For example, a better understanding of these systems has enabled the rapid development of quantum dots with precisely determined properties, which can be exploited in a range of applications from medical imaging and photovoltaic solar cells to quantum computation, a radically new information technology being currently developed in many labs worldwide. As the first ever academic journal in nanotechnology, {\\it Nanotechnology} has been the forum for papers detailing progress of the science through extremely exciting times. In the early years of the journal, the investigation of electron spin led to the formulation

  1. Poorly studied phenomena in geoelectrics

    Directory of Open Access Journals (Sweden)

    В. С. Могилатов

    2016-12-01

    Full Text Available Undoubtedly, modern geoelectric technologies emerge in the result of the development of traditional approaches and techniques. However of more interest is the appearance of completely new technologies based on new effects and new models of interaction of geological medium and electromagnetic field. The author does not commit to indicate principally new directions, but only wants to discuss some poorly known facts from the theory and practice of geoelectrics. The outcome of this study could be considered attracting the attention of experts to non-traditional signals in geoelectrics. The reviewed phenomena of interest, not fully implemented in practice in the author’s opinion, are field split into two polarizations: transverse electric (the ТЕ-field and transverse magnetic (the ТМ-field, then some poorly known properties of ТМ-field, the role of bias currents, the anisotropy of horizontal resistances, the role of geomagnetic field in geoelectric sounding, the unique resolution of CSEM (Controlled Source Electro-Magnetic techniques at sea.

  2. Transient phenomena in multiphase flow

    International Nuclear Information System (INIS)

    Afgan, N.H.

    1988-01-01

    This book is devoted to formulation of the two-phase system. Emphasis is given to classical instantaneous equations of mass momentum and energy for local conditions and respective averaging procedures and their relevance to the structure of transfer laws. In formulating an equation for a two-velocity continuum, two-phase dispersed flow, two-velocity and local inertial effects associated with contraction and expansion of the mixture have been considered. Particular attention is paid to the effects of interface topology and area concentration as well as the latter's dependence on interfacial transfer laws. Also covered are low bubble concentrations in basic nonuniform unsteady flow where interactions between bubbles are negligible but where the effects of bubbles must still be considered. Special emphasis has been given to the pairwise interaction of the bubble and respective hydrodynamic equations describing the motion of a pair of spherical bubbles through a liquid This book introduces turbulence phenomena in two-phase flow and related problems of phase distribution in two-phase flow. This includes an extensive survey of turbulence and phase distribution models in transient two-phase flow. It is shown that if the turbulent structure of the continuous phase of bubbly two-phase is either measured or can be predicted, then the observed lateral phase distribution can be determined by using an multidimensional two-fluid model in which all lateral forces are properly modeled

  3. Electrostatic phenomena in volcanic eruptions

    Energy Technology Data Exchange (ETDEWEB)

    Lane, S J; James, M R; Gilbert, J S, E-mail: s.lane@lancaster.ac.uk [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2011-06-23

    Electrostatic phenomena have long been associated with the explosive eruption of volcanoes. Lightning generated in volcanic plumes is a spectacular atmospheric electrical event that requires development of large potential gradients over distances of up to kilometres. This process begins as hydrated liquid rock (magma) ascends towards Earth's surface. Pressure reduction causes water supersaturation in the magma and the development of bubbles of supercritical water, where deeper than c. 1000 m, and water vapour at shallower depths that drives flow expansion. The generation of high strain rates in the expanding bubbly magma can cause it to fracture in a brittle manner, as deformation relaxation timescales are exceeded. The brittle fracture provides the initial charge separation mechanism, known as fractoemission. The resulting mixture of charged silicate particles and ions evolves over time, generating macro-scale potential gradients in the atmosphere and driving processes such as particle aggregation. For the silicate particles, aggregation driven by electrostatic effects is most significant for particles smaller than c. 100 {mu}m. Aggregation acts to change the effective aerodynamic behaviour of silicate particles, thus altering the sedimentation rates of particles from volcanic plumes from the atmosphere. The presence of liquid phases also promotes aggregation processes and lightning.

  4. Mixed Fluid Conditions: Capillary Phenomena

    KAUST Repository

    Santamarina, Carlos

    2017-07-06

    Mixed fluid phenomena in porous media have profound implications on soil-atmosphere interaction, energy geotechnology, environmental engineering and infrastructure design. Surface tension varies with pressure, temperature, solute concentration, and surfactant concentration; on the other hand, the contact angle responds to interfacial tensions, surface topography, invasion velocity, and chemical interactions. Interfaces are not isolated but interact through the fluid pressure and respond to external fields. Jumps, snap-offs and percolating wetting liquids along edges and crevices are ubiquitous in real, non-cylindrical porous networks. Pore- and macroscale instabilities together with pore structure variability-and-correlation favor fluid trapping and hinder recovery efficiency. The saturation-pressure characteristic curve is affected by the saturation-history, flow-rate, the mechanical response of the porous medium, and time-dependent reactive and diffusive processes; in addition, there are salient differences between unsaturation by internal gas nucleation and gas invasion. Capillary forces add to other skeletal forces in the porous medium and can generate open-mode discontinuities when the capillary entry pressure is high relative to the effective stress. Time emerges as an important variable in mixed-fluid conditions and common quasi-static analyses may fail to capture the system response.

  5. Kidney damage in extracorporeal shock wave lithotripsy: a numerical approach for different shock profiles.

    Science.gov (United States)

    Weinberg, Kerstin; Ortiz, Michael

    2009-08-01

    In shock-wave lithotripsy--a medical procedure to fragment kidney stones--the patient is subjected to hypersonic waves focused at the kidney stone. Although this procedure is widely applied, the physics behind this medical treatment, in particular the question of how the injuries to the surrounding kidney tissue arise, is still under investigation. To contribute to the solution of this problem, two- and three-dimensional numerical simulations of a human kidney under shock-wave loading are presented. For this purpose a constitutive model of the bio-mechanical system kidney is introduced, which is able to map large visco-elastic deformations and, in particular, material damage. The specific phenomena of cavitation induced oscillating bubbles is modeled here as an evolution of spherical pores within the soft kidney tissue. By means of large scale finite element simulations, we study the shock-wave propagation into the kidney tissue, adapt unknown material parameters and analyze the resulting stress states. The simulations predict localized damage in the human kidney in the same regions as observed in animal experiments. Furthermore, the numerical results suggest that in first instance the pressure amplitude of the shock wave impulse (and not so much its exact time-pressure profile) is responsible for damaging the kidney tissue.

  6. Discrimination of Thermal versus Mechanical Effects of Shock on Rock Magnetic Properties of Spherically Shocked up to 10-160 GPa Basalt and Diabase

    Science.gov (United States)

    Bezaeva, N. S.; Swanson-Hysell, N.; Tikoo, S.; Badyukov, D. D.; Kars, M. A. C.; Egli, R.; Chareev, D. A.; Fairchild, L. M.

    2016-12-01

    Understanding how shock waves generated during hypervelocity impacts affect rock magnetic properties is key for interpreting the paleomagnetic records of lunar rocks, meteorites, and cratered planetary surfaces. Laboratory simulations of impacts show that ultra-high shocks may induce substantial post-shock heating of the target material. At high pressures (>10 GPa), shock heating occurs in tandem with mechanical effects, such as grain fracturing and creation of crystallographic defects and dislocations within magnetic grains. This makes it difficult to conclude whether shock-induced changes in the rock magnetic properties of target materials are primarily associated with mechanical or thermal effects. Here we present novel experimental methods to discriminate between mechanical and thermal effects of shock on magnetic properties and illustrate it with two examples of spherically shocked terrestrial basalt and diabase [1], which were shocked to pressures of 10 to >160 GPa, and investigate possible explanations for the observed shock-induced magnetic hardening (i.e., increase in remanent coercivity Bcr). The methods consist of i) conducting extra heating experiments at temperatures resembling those experienced during high-pressure shock events on untreated equivalents of shocked rocks (with further comparison of Bcr of shocked and heated samples) and ii) quantitative comparison of high-resolution first-order reversal curve (FORC) diagrams (field step: 0.5-0.7 mT) for shocked, heated and untreated specimens. Using this approach, we demonstrated that the shock-induced coercivity hardening in our samples is predominantly due to solid-state, mechanical effects of shock rather than alteration associated with shock heating. Indeed, heating-induced changes in Bcr in the post-shock temperature range were minor. Visual inspection of FORC contours (in addition to detailed analyses) reveals a stretching of the FORC distribution of shocked sample towards higher coercivities

  7. Development of Calculation Algorithm for ECCS Kinematic Shock

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Chan; Yoon, Duk-Joo; Ha, Sang-Jun [KHNP-CRI, Daejeon (Korea, Republic of)

    2014-10-15

    The void fraction of inverted U-pipes in front of SI(Safety Injection) pumps impact on the pipe system of ECCS(Emergency Core Cooling Systems). This phenomena is called as 'Kinematic Shock'. The purpose of this paper is to achieve the more exactly calculation when the kinematic shock is calculated by simplified equation. The behavior of the void packet of the ECCS pipes is illustrated by the simplified (other name is kinematic shock equation).. The kinematic shock is defined as the depth of total length of void clusters in the pipes of ECCS when the void cluster is continually reached along the part of pipes in vertical direction. In this paper, the simplified equation is evaluated by comparing calculation error each other.]. The more exact methods of calculating the depth of the kinematic shock in ECCS is achieved. The error of kinematic shock calculation is strongly depended on the calculation search gap and the order of Taylor's expansion. From this study, to select the suitable search gap and the suitable calculation order, differential root method, secant method, and Taylor's expansion form are compared one another.

  8. Nonlinear theory of diffusive acceleration of particles by shock waves

    Energy Technology Data Exchange (ETDEWEB)

    Malkov, M.A. [University of California at San Diego, La Jolla, CA (United States)]. E-mail: mmalkov@ucsd.edu; Drury, L. O' C. [Dublin Institute for Advanced Studies, 5 Merrion Square, Dublin 2 (Ireland)

    2001-04-01

    Among the various acceleration mechanisms which have been suggested as responsible for the nonthermal particle spectra and associated radiation observed in many astrophysical and space physics environments, diffusive shock acceleration appears to be the most successful. We review the current theoretical understanding of this process, from the basic ideas of how a shock energizes a few reactionless particles to the advanced nonlinear approaches treating the shock and accelerated particles as a symbiotic self-organizing system. By means of direct solution of the nonlinear problem we set the limit to the test-particle approximation and demonstrate the fundamental role of nonlinearity in shocks of astrophysical size and lifetime. We study the bifurcation of this system, proceeding from the hydrodynamic to kinetic description under a realistic condition of Bohm diffusivity. We emphasize the importance of collective plasma phenomena for the global flow structure and acceleration efficiency by considering the injection process, an initial stage of acceleration and, the related aspects of the physics of collisionless shocks. We calculate the injection rate for different shock parameters and different species. This, together with differential acceleration resulting from nonlinear large-scale modification, determines the chemical composition of accelerated particles. The review concentrates on theoretical and analytical aspects but our strategic goal is to link the fundamental theoretical ideas with the rapidly growing wealth of observational data. (author)

  9. A numerical study on bow shocks around the lightning return stroke channel

    International Nuclear Information System (INIS)

    Chen, Qiang; Chen, Bin; Yi, Yun; Chen, P. F.; Mao, Yunfei; Xiong, Run

    2015-01-01

    Bow shock structures are important to various hydrodynamics and magnetohydrodynamics (MHD) phenomena in geophysics and astrophysics. The formation and propagation of bow shocks around the lightning return stroke channel are investigated based on the self-similar motion theory and simulated with a two-dimensional Eulerian finite volume resistive radiation MHD code. In this framework, as verification of theoretical models, the evolving structures of many quantities, such as the plasma density, temperature, pressure, shock velocity, and magnetic field, can be obtained, which present all the characteristics of bow shocks in the lightning return stroke processes. The evolution characteristics and the configuration of the curved return stroke channels, e.g., the non-ideal effects and the scaling laws, are discussed in detail. The results may have applications for some observed features of the return stroke channels and other phenomena in the lightning discharge plasmas

  10. Observation of Celestial Phenomena in Ancient China

    Science.gov (United States)

    Sun, Xiaochun

    Because of the need for calendar-making and portent astrology, the Chinese were diligent and meticulous observers of celestial phenomena. China has maintained the longest continuous historical records of celestial phenomena in the world. Extraordinary or abnormal celestial events were particularly noted because of their astrological significance. The historical records cover various types of celestial phenomena, which include solar and lunar eclipses, sunspots, "guest stars" (novae or supernovae as we understand today), comets and meteors, and all kinds of planetary phenomena. These records provide valuable historical data for astronomical studies today.

  11. Shocks in fragile matter

    Science.gov (United States)

    Vitelli, Vincenzo

    2012-02-01

    Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they unjam, these fragile and disordered solids exhibit vanishing elastic moduli and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are continuously compressed, and demonstrate that the resulting excitations are strongly nonlinear shocks, rather than linear waves. We capture the full dependence of the shock speed on pressure and compression speed by a surprisingly simple analytical model. We also treat shear shocks within a simplified viscoelastic model of nearly-isostatic random networks comprised of harmonic springs. In this case, anharmonicity does not originate locally from nonlinear interactions between particles, as in granular media; instead, it emerges from the global architecture of the network. As a result, the diverging width of the shear shocks bears a nonlinear signature of the diverging isostatic length associated with the loss of rigidity in these floppy networks.

  12. Admissibility region for rarefaction shock waves in dense gases

    OpenAIRE

    Zamfirescu, C.; Guardone, A.; Colonna, P.

    2008-01-01

    In the vapour phase and close to the liquid–vapour saturation curve, fluids made of complex molecules are expected to exhibit a thermodynamic region in which the fundamental derivative of gasdynamic ? is negative. In this region, non-classical gasdynamic phenomena such as rarefaction shock waves are physically admissible, namely they obey the second law of thermodynamics and fulfil the speed-orienting condition for mechanical stability. Previous studies have demonstrated that the thermodynami...

  13. Physics of Collisionless Shocks Space Plasma Shock Waves

    CERN Document Server

    Balogh, André

    2013-01-01

    The present book provides a contemporary systematic treatment of shock waves in high-temperature collisionless plasmas as are encountered in near Earth space and in Astrophysics. It consists of two parts. Part I develops the complete theory of shocks in dilute hot plasmas under the assumption of absence of collisions among the charged particles when the interaction is mediated solely by the self-consistent electromagnetic fields. Such shocks are naturally magnetised implying that the magnetic field plays an important role in their evolution and dynamics. This part treats both subcritical shocks, which dissipate flow energy by generating anomalous resistance or viscosity, and supercritical shocks. The main emphasis is, however, on super-critical shocks where the anomalous dissipation is insufficient to retard the upstream flow. These shocks, depending on the direction of the upstream magnetic field, are distinguished as quasi-perpendicular and quasi-parallel shocks which exhibit different behaviours, reflecti...

  14. Life Shocks and Homelessness

    Science.gov (United States)

    Corman, Hope; Noonan, Kelly; Reichman, Nancy E.

    2014-01-01

    We exploited an exogenous health shock—namely, the birth of a child with a severe health condition—to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

  15. Health Shocks and Retirement:

    DEFF Research Database (Denmark)

    Datta Gupta, Nabanita; Larsen, Mona

    We investigate the effect of an acute health shock on retirement among elderly male workers in Denmark, 1991-1999, and in particular whether various welfare state programs and institutions impinge on the retirement effect. The results show that an acute health event increases the retirement chances...... significant. For the most part, the retirement effect following a health shock seems to be immune to the availability of a multitude of government programs for older workers in Denmark....... benefits in Denmark nor by the promotion of corporate social responsibility initiatives since the mid-1990s. In the late 1990s, however, the retirement rate following a health shock is reduced to 3% with the introduction of the subsidized employment program (fleksjob) but this effect is not strongly...

  16. Back to Bentham? Explorations of Experienced Utility

    OpenAIRE

    Kahneman, Daniel; Wakker, Peter; Sarin, Rakesh

    1997-01-01

    textabstractTwo core meanings of “utility” are distinguished. “Decision utility” is the weight of an outcome in a decision. “Experienced utility” is hedonic quality, as in Bentham’s usage. Experienced utility can be reported in real time (instant utility), or in retrospective evaluations of past episodes (remembered utility). Psychological research has documented systematic errors in retrospective evaluations, which can induce a preference for dominated options. We propose a formal normative ...

  17. The Shock Routine

    DEFF Research Database (Denmark)

    van Hooren, Franca; Kaasch, Alexandra; Starke, Peter

    2014-01-01

    in Australia, Belgium, the Netherlands and Sweden over the course of four global economic shocks, we ask whether the notion of critical junctures is useful in understanding the nature of change triggered by crisis. The main empirical finding is that fundamental change in the aftermath of an exogenous shock...... is the exception rather than the rule. Instead, incremental ‘crisis routines’ based on existing policy instruments are overwhelmingly used to deal with economic hardship. We discuss these findings in the light of the psychological ‘threat-rigidity’ effect and reflect on their consequences for theories...

  18. Experiencing Light's Properties within Your Own Eye

    Science.gov (United States)

    Mauser, Michael

    2011-01-01

    Seeing the reflection, refraction, dispersion, absorption, polarization, and scattering or diffraction of light within your own eye makes these properties of light truly personal. There are practical aspects of these within the eye phenomena, such as eye tracking for computer interfaces. They also offer some intriguing diversions, for example,…

  19. PREFACE Integrability and nonlinear phenomena Integrability and nonlinear phenomena

    Science.gov (United States)

    Gómez-Ullate, David; Lombardo, Sara; Mañas, Manuel; Mazzocco, Marta; Nijhoff, Frank; Sommacal, Matteo

    2010-10-01

    Back in 1967, Clifford Gardner, John Greene, Martin Kruskal and Robert Miura published a seminal paper in Physical Review Letters which was to become a cornerstone in the theory of integrable systems. In 2006, the authors of this paper received the AMS Steele Prize. In this award the AMS pointed out that `In applications of mathematics, solitons and their descendants (kinks, anti-kinks, instantons, and breathers) have entered and changed such diverse fields as nonlinear optics, plasma physics, and ocean, atmospheric, and planetary sciences. Nonlinearity has undergone a revolution: from a nuisance to be eliminated, to a new tool to be exploited.' From this discovery the modern theory of integrability bloomed, leading scientists to a deep understanding of many nonlinear phenomena which is by no means reachable by perturbation methods or other previous tools from linear theories. Nonlinear phenomena appear everywhere in nature, their description and understanding is therefore of great interest both from the theoretical and applicative point of view. If a nonlinear phenomenon can be represented by an integrable system then we have at our disposal a variety of tools to achieve a better mathematical description of the phenomenon. This special issue is largely dedicated to investigations of nonlinear phenomena which are related to the concept of integrability, either involving integrable systems themselves or because they use techniques from the theory of integrability. The idea of this special issue originated during the 18th edition of the Nonlinear Evolution Equations and Dynamical Systems (NEEDS) workshop, held at Isola Rossa, Sardinia, Italy, 16-23 May 2009 (http://needs-conferences.net/2009/). The issue benefits from the occasion offered by the meeting, in particular by its mini-workshops programme, and contains invited review papers and contributed papers. It is worth pointing out that there was an open call for papers and all contributions were peer reviewed

  20. Nonlinear dynamical phenomena in liquid crystals

    International Nuclear Information System (INIS)

    Wang, X.Y.; Sun, Z.M.

    1988-09-01

    Because of the existence of the orientational order and anisotropy in liquid crystals, strong nonlinear phenomena and singular behaviors, such as solitary wave, transient periodic structure, chaos, fractal and viscous fingering, can be excited by a very small disturbance. These phenomena and behaviors are in connection with physics, biology and mathematics. 12 refs, 6 figs

  1. Polarization phenomena in heavy-ion reactions

    International Nuclear Information System (INIS)

    Sugimoto, K.; Ishihara, M.; Takahashi, N.

    1984-01-01

    This chapter presents a few key experiments which provide direct evidence of the polarization phenomena in heavy-ion reactions. The theory of polarization observables and measurements is given with the necessary formulae. The polarization phenomena is described and studies of product nuclear polarization in heavy-ion reactions are discussed. Studies of heavy-ion reactions induced by polarized beams are examined

  2. A Connection between Transport Phenomena and Thermodynamics

    Science.gov (United States)

    Swaney, Ross; Bird, R. Byron

    2017-01-01

    Although students take courses in transport phenomena and thermodynamics, they probably do not ask whether these two subjects are related. Here we give an answer to that question. Specifically we give relationships between the equations of change for total energy, internal energy, and entropy of transport phenomena and key equations of equilibrium…

  3. Shock absorber in Ignalina NPP

    International Nuclear Information System (INIS)

    Bulavas, A.; Muralis, J.

    1996-09-01

    Theoretical calculation and experimental analysis of models of shock absorber in Ignalina NPP is presented. The results obtained from the investigation with model of shock absorber coincide with the theoretical calculation. (author). 2 figs., 3 refs

  4. Shock Response of Boron Carbide

    National Research Council Canada - National Science Library

    Dandekar, D. P. (Dattatraya Purushottam)

    2001-01-01

    .... The present work was undertaken to determine tensile/spall strength of boron carbide under plane shock wave loading and to analyze all available shock compression data on boron carbide materials...

  5. Fascinating World of Shock Waves

    Indian Academy of Sciences (India)

    Srimath

    travelling at supersonic speeds (more than the sound speed at ... actual earth- quake, travel at supersonic speeds. .... The time scale of the shock wave is also important ..... real lithotripsy where a shock wave is used shatter the kidney stones!

  6. Precedent Phenomena in Quebecois Linguistic World View

    Directory of Open Access Journals (Sweden)

    Ксения Эдуардовна Болотина

    2016-12-01

    Full Text Available This article is devoted to the linguocultural analysis of precedent phenomena as parts of Quebecois’ cognitive base. Precedent phenomena being cultural facts are one of the key issues in modern linguistic and cognitive studies. By precedent phenomena we mean, according to Y.E. Prohorov, such entities when verbalized in discourse that refer to a certain cultural fact behind them. In the article the precedent phenomena such as precedent text, precedent situation, precedent utterance, and precedent name are analyzed. The main theses of the precedence theory given in the article (Y.N. Karaulov, Y.E. Prohorov, V.V. Krasnyh, D.B. Gudkov are at the heart of precedence studies on the basis of different languages. However, a complex analysis of precedent phenomena in the Quebec national variant of French is new to Russian linguistics. The study of precedent phenomena enables us to elicit features of their functioning in ethnospecific discourse and determine cultural dominants existing in Quebecois’ linguistic world view. Given the fact that the size of the article is limited, we undertooke the analysis of eight phenomena precedent of the bearers of Quebec linguoculture. The choice of phenomena is determined by the frequency of their use in discourse. The facts analyzed are of national character, i.e. known to all members of the linguocultural community. A certain cultural fact is at the very core of each precedent phenomenon given in the article. To get the whole picture we analysed historic, political, and cultural context connected to the precedent phenomena in question. The study enables us to elicit distinctive features that are at the core of each phenomenon. The results are backed with the supportive material drawn from analysis of different types of discourse. The analysis of precedent phenomena undertaken in this article allows us to reconstruct, to a certain extent, Quebec cultural space and is a stepping stone to the reconstruction of the

  7. INTERFERENCE OF UNIDIRECTIONAL SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-05-01

    Full Text Available Subject of study.We consider interference of unidirectional shock waves or, as they are called, catching up shock waves. The scope of work is to give a classification of the shock-wave structures that arise in this type of interaction of shock waves, and the area of their existence. Intersection of unidirectional shock waves results in arising of a shock-wave structure at the intersection point, which contains the main shock wave, tangential discontinuity and one more reflected gas-dynamic discontinuity of unknown beforehand type. The problem of determining the type of reflected discontinuity is the main problem that one has to solve in the study of catching shock waves interference. Main results.The paper presents the pictures of shock-wave structures arising at the interaction of catching up shock waves. The areas with a regular and irregular unidirectional interaction of shocks are described. Characteristic shock-wave structures are of greatest interest, where reflected gas-dynamic discontinuity degenerates into discontinuous characteristics. Such structures have a number of extreme properties. We have found the areas of existence for such shock-wave structures. There are also areas in which the steady-state solution is not available. The latter has determined revival of interest for the theoretical study of the problem, because the facts of sudden shock-wave structure destruction inside the air intake of supersonic aircrafts at high Mach numbers have been discovered. Practical significance.The theory of interference for unidirectional shock waves and design procedure are usable in the design of supersonic air intakes. It is also relevant for application possibility investigation of catching up oblique shock waves to create overcompressed detonation in perspective detonation air-jet and rocket engines.

  8. Teleconnected food supply shocks

    Science.gov (United States)

    Bren d'Amour, Christopher; Wenz, Leonie; Kalkuhl, Matthias; Steckel, Jan Christoph; Creutzig, Felix

    2016-03-01

    The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks.

  9. STEREO interplanetary shocks and foreshocks

    International Nuclear Information System (INIS)

    Blanco-Cano, X.; Kajdič, P.; Aguilar-Rodríguez, E.; Russell, C. T.; Jian, L. K.; Luhmann, J. G.

    2013-01-01

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and θ Bn ∼20-86°. We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr ≤0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at ∼1 AU and have been producing suprathermal particles for a shorter time.

  10. STEREO interplanetary shocks and foreshocks

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Cano, X. [Instituto de Geofisica, UNAM, CU, Coyoacan 04510 DF (Mexico); Kajdic, P. [IRAP-University of Toulouse, CNRS, Toulouse (France); Aguilar-Rodriguez, E. [Instituto de Geofisica, UNAM, Morelia (Mexico); Russell, C. T. [ESS and IGPP, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095 (United States); Jian, L. K. [NASA Goddard Space Flight Center, Greenbelt, MD and University of Maryland, College Park, MD (United States); Luhmann, J. G. [SSL, University of California Berkeley (United States)

    2013-06-13

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and {theta}{sub Bn}{approx}20-86 Degree-Sign . We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr {<=}0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at {approx}1 AU and have been producing suprathermal particles for a shorter time.

  11. Development of a General Shocked-Materials-Response Description for Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Steven M. Valone

    2000-07-01

    This report outlines broad modeling issues pertaining to polymeric materials behavior under detonation conditions. Models applicable system wide are necessary to cope with the broad range of polymers and complex composite forms that can appear in Laboratory weapons systems. Nine major topics are discussed to span the breadth of materials, forms, and physical phenomena encountered when shocking polymers and foams over wide ranges of temperatures, pressures, shock strengths, confinement conditions, and geometries. The recommendations for directions of more intensive investigation consider physical fidelity, computational complexity, and application over widely varying physical conditions of temperature, pressure, and shock strength.

  12. Shock Dynamics in Stellar Outbursts. I. Shock Formation

    Energy Technology Data Exchange (ETDEWEB)

    Ro, Stephen; Matzner, Christopher D., E-mail: ro@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)

    2017-05-20

    Wave-driven outflows and non-disruptive explosions have been implicated in pre-supernova outbursts, supernova impostors, luminous blue variable eruptions, and some narrow-line and superluminous supernovae. To model these events, we investigate the dynamics of stars set in motion by strong acoustic pulses and wave trains, focusing on nonlinear wave propagation, shock formation, and an early phase of the development of a weak shock. We identify the shock formation radius, showing that a heuristic estimate based on crossing characteristics matches an exact expansion around the wave front and verifying both with numerical experiments. Our general analytical condition for shock formation applies to one-dimensional motions within any static environment, including both eruptions and implosions. We also consider the early phase of shock energy dissipation. We find that waves of super-Eddington acoustic luminosity always create shocks, rather than damping by radiative diffusion. Therefore, shock formation is integral to super-Eddington outbursts.

  13. The Use of Shock Isolation mounts in Small High-Speed Craft to Protect Equipment from Wave Slam Effects

    Science.gov (United States)

    2017-07-01

    hardware, but caution is advised because effective solutions will likely only be achieved by experienced shock isolation designers who pursue unique...provide tractable isolation solutions for craft, but caution is advised because effective solutions will likely only be achieved by experienced...very short duration of local vibration oscillations (e.g., nominal 25 to 50 msec or less) rather than rigid body shock pulse durations (e.g., 100

  14. Interfacial polarization phenomena in organic molecular films

    International Nuclear Information System (INIS)

    Iwamoto, Mitsumasa; Manaka, Takaaki

    2006-01-01

    Electrostatic phenomena occurring at the interface between metal/organic and organic/organic materials are discussed from the viewpoint of dielectrics physics. Focusing on two important origins of surface polarization phenomena, orientational ordering of polar molecules and displacement of excess charges at the interface, surface polarization phenomena of organic thin films are discussed. To define the orientational order of polar molecules, orientational order parameters are introduced, and surface polarization due to the alignment of dipoles is expressed. The generation of Maxwell displacement current (MDC) and optical second harmonic generation (SHG) that are specific for surface organic monomolecular films are discussed, and some experimental evidence are shown. As an extension of the concept of surface Fermi level introduced to discuss the electrostatic phenomena due to electron transfer at the interface between metal-organic insulators, the surface Fermi level is extended to the discussion on the electrostatic phenomena of organic semiconductor materials on metals. In this paper, some experimental evidence of surface polarization originating from polar molecules and displacement of excess charges are shown. After that, with consideration of these surface phenomena, single electron tunneling of organic films are briefly discussed in association with surface polarization phenomena

  15. A statistical approach to strange diffusion phenomena

    International Nuclear Information System (INIS)

    Milligen, B.Ph. van; Carreras, B.A.; Sanchez, R.

    2005-01-01

    The study of particle (and heat) transport in fusion plasmas has revealed the existence of what might be called 'unusual' transport phenomena. Such phenomena are: unexpected scaling of the confinement time with system size, power degradation (i.e. sub-linear scaling of energy content with power input), profile stiffness (also known as profile consistency), rapid transient transport phenomena such as cold and heat pulses (travelling much faster than the diffusive timescale would allow), non-local behaviour and central profile peaking during off-axis heating, associated with unexplained inward pinches. The standard modelling framework, essentially equal to Fick's Law plus extensions, has great difficulty in providing an all-encompassing and satisfactory explanation of all these phenomena. This difficulty has motivated us to reconsider the basics of the modelling of diffusive phenomena. Diffusion is based on the well-known random walk. The random walk is captured in all its generality in the Continuous Time Random Walk (CTRW) formalism. The CTRW formalism is directly related to the well-known Generalized Master Equation, which describes the behaviour of tracer particle diffusion on a very fundamental level, and from which the phenomenological Fick's Law can be derived under some specific assumptions. We show that these assumptions are not necessarily satisfied under fusion plasma conditions, in which case other equations (such as the Fokker-Planck diffusion law or the Master Equation itself) provide a better description of the phenomena. This fact may explain part of the observed 'strange' phenomena (namely, the inward pinch). To show how the remaining phenomena mentioned above may perhaps find an explanation in the proposed alternative modelling framework, we have designed a toy model that incorporates a critical gradient mechanism, switching between rapid (super-diffusive) and normal diffusive transport as a function of the local gradient. It is then demonstrated

  16. Fourteenth International Conference on Ultrafast Phenomena

    CERN Document Server

    Kobayashi, Takayoshi; Kobayashi, Tetsuro; Nelson, Keith A; Silvestri, Sandro; Ultrafast Phenomena XIV

    2005-01-01

    Ultrafast Phenomena XIV presents the latest advances in ultrafast science, including ultrafast laser and measurement technology as well as studies of ultrafast phenomena. Pico-, femto-, and atosecond processes relevant in physics, chemistry, biology and engineering are presented. Ultrafast technology is now having a profound impact within a wide range of applications, among them imaging, material diagnostics, and transformation and high-speed optoelectronics. This book summarizes results presented at the 14th Ultrafast Phenomena Conference and reviews the state of the art in this important and rapidly advancing field.

  17. Transient phenomena in electrical power systems

    CERN Document Server

    Venikov, V A; Higinbotham, W

    1964-01-01

    Electronics and Instrumentation, Volume 24: Transient Phenomena in Electrical Power Systems presents the methods for calculating the stability and the transient behavior of systems with forced excitation control. This book provides information pertinent to the analysis of transient phenomena in electro-mechanical systems.Organized into five chapters, this volume begins with an overview of the principal requirements in an excitation system. This text then explains the electromagnetic and electro-mechanical phenomena, taking into account the mutual action between the components of the system. Ot

  18. Computational transport phenomena for engineering analyses

    CERN Document Server

    Farmer, Richard C; Cheng, Gary C; Chen, Yen-Sen

    2009-01-01

    Computational Transport PhenomenaOverviewTransport PhenomenaAnalyzing Transport PhenomenaA Computational Tool: The CTP CodeVerification, Validation, and GeneralizationSummaryNomenclatureReferencesThe Equations of ChangeIntroductionDerivation of The Continuity EquationDerivation of The Species Continuity EquationDerivation of The Equation Of MotionDerivation of The General Energy EquationNon-Newtonian FluidsGeneral Property BalanceAnalytical and Approximate Solutions for the Equations of ChangeSummaryNomenclatureReferencesPhysical PropertiesOverviewReal-Fluid ThermodynamicsChemical Equilibrium

  19. Nonlinear Photonics and Novel Optical Phenomena

    CERN Document Server

    Morandotti, Roberto

    2012-01-01

    Nonlinear Photonics and Novel Optical Phenomena contains contributed chapters from leading experts in nonlinear optics and photonics, and provides a comprehensive survey of fundamental concepts as well as hot topics in current research on nonlinear optical waves and related novel phenomena. The book covers self-accelerating airy beams, integrated photonics based on high index doped-silica glass, linear and nonlinear spatial beam dynamics in photonic lattices and waveguide arrays, polariton solitons and localized structures in semiconductor microcavities, terahertz waves, and other novel phenomena in different nanophotonic and optical systems.

  20. Sixteenth International Conference on Ultrafast Phenomena

    CERN Document Server

    Corkum, Paul; Nelson, Keith A; Riedle, Eberhard; Schoenlein, Robert W; Ultrafast Phenomena XVI

    2009-01-01

    Ultrafast Phenomena XVI presents the latest advances in ultrafast science, including both ultrafast optical technology and the study of ultrafast phenomena. It covers picosecond, femtosecond and attosecond processes relevant to applications in physics, chemistry, biology, and engineering. Ultrafast technology has a profound impact in a wide range of applications, amongst them biomedical imaging, chemical dynamics, frequency standards, material processing, and ultrahigh speed communications. This book summarizes the results presented at the 16th International Conference on Ultrafast Phenomena and provides an up-to-date view of this important and rapidly advancing field.

  1. Heat transfer phenomena revelant to severe accidents

    International Nuclear Information System (INIS)

    Dallman, R.J.; Duffey, R.B.

    1990-01-01

    A number of aspects of severe accidents have been reviewed, particularly in relation to the heat transfer characteristics and the important phenomena. It is shown that natural circulation, forced convection, and entrainment phenomena are important for both the reactor system and ex-vessel events. It is also shown that the phenomena related to two component enhanced heat transfer is important in the pool of molten core debris, in relation to the potential for attack of the liner structure and the concrete. These mechanisms are discussed within the general context of severe accident progression

  2. Developing Phenomena Models from Experimental Data

    DEFF Research Database (Denmark)

    Kristensen, Niels Rode; Madsen, Henrik; Jørgensen, Sten Bay

    2003-01-01

    A systematic approach for developing phenomena models from experimental data is presented. The approach is based on integrated application of stochastic differential equation (SDE) modelling and multivariate nonparametric regression, and it is shown how these techniques can be used to uncover...... unknown functionality behind various phenomena in first engineering principles models using experimental data. The proposed modelling approach has significant application potential, e.g. for determining unknown reaction kinetics in both chemical and biological processes. To illustrate the performance...... of the approach, a case study is presented, which shows how an appropriate phenomena model for the growth rate of biomass in a fed-batch bioreactor can be inferred from data....

  3. Developing Phenomena Models from Experimental Data

    DEFF Research Database (Denmark)

    A systematic approach for developing phenomena models from experimental data is presented. The approach is based on integrated application of stochastic differential equation (SDE) modelling and multivariate nonparametric regression, and it is shown how these techniques can be used to uncover...... unknown functionality behind various phenomena in first engineering principles models using experimental data. The proposed modelling approach has significant application potential, e.g. for determining unknown reaction kinetics in both chemical and biological processes. To illustrate the performance...... of the approach, a case study is presented, which shows how an appropriate phenomena model for the growth rate of biomass in a fed-batch bioreactor can be inferred from data....

  4. Heat transfer phenomena relevant to severe accidents

    International Nuclear Information System (INIS)

    Dallman, R.J.; Duffey, R.B.

    1990-01-01

    A number of aspects of severe accidents have been reviewed, particularly in relation to the heat transfer characteristics and the important phenomena. It is shown that natural circulation, forced convection, and entrainment phenomena are important for both the reactor system and ex-vessel events. It is also shown that the phenomena related to two component enhanced heat transfer is important in the pool of molten core debris, in relation to the potential for attack of the liner structure and the concrete. These mechanisms are discussed within the general context of severe accident progression. 26 refs

  5. Grain destruction in interstellar shocks

    International Nuclear Information System (INIS)

    Seab, C.G.; Shull, J.M.

    1984-01-01

    One of the principal methods for removing grains from the Interstellar Medium is to destroy them in shock waves. Previous theoretical studies of shock destruction have generally assumed only a single size and type of grain; most do not account for the effect of the grain destruction on the structure of the shock. Earlier calculations have been improved in three ways: first, by using a ''complete'' grain model including a distribution of sizes and types of grains; second, by using a self-consistent shock structure that incorporates the changing elemental depletions as the grains are destroyed; and third, by calculating the shock-processed ultraviolet extinction curves for comparison with observations. (author)

  6. Experimental research on crossing shock wave boundary layer interactions

    Science.gov (United States)

    Settles, G. S.; Garrison, T. J.

    1994-10-01

    An experimental research effort of the Penn State Gas Dynamics Laboratory on the subject of crossing shock wave boundary layer interactions is reported. This three year study was supported by AFOSR Grant 89-0315. A variety of experimental techniques were employed to study the above phenomena including planar laser scattering flowfield visualization, kerosene lampblack surface flow visualization, laser-interferometer skin friction surveys, wall static pressure measurements, and flowfield five-hole probe surveys. For a model configuration producing two intersecting shock waves, measurements were made for a range of oblique shock strengths at freestream Mach numbers of 3.0 and 3.85. Additionally, measurements were made at Mach 3.85 for a configuration producing three intersecting waves. The combined experimental dataset was used to formulate the first detailed flowfield models of the crossing-shock and triple-shock wave/boundary layer interactions. The structure of these interactions was found to be similar over a broad range of interaction strengths and is dominated by a large, separated, viscous flow region.

  7. Lower hybrid waves at the shock front: a reassessment

    Directory of Open Access Journals (Sweden)

    S. N. Walker

    2008-03-01

    Full Text Available The primary process occurring at a collisionless shock is the redistribution of the bulk upstream energy into other degrees of freedom. One part of this process results in the acceleration of electrons at the shock front. Accelerated electrons are observed at the terrestrial and other planetary shocks, comets, and their effects are observed in astrophysical phenomena such as supernova remnants and jets in the form of X-ray bremsstrahlung radiation. One of the physical models for electron acceleration at supercritical shocks is based on low-hybrid turbulence due to the presence of reflected ions in the foot region. Since lower hybrid waves propagate almost perpendicular to the magnetic field they can be simultaneously in resonance with both the unmagnetised ions (ω=Vik⊥ and magnetised electrons (ω=Vek||. In this paper, Cluster observations of the electric field are used to study the occurrence of lower hybrid waves in the front of the terrestrial bow shock. It is shown that the lower hybrid waves exist as isolated wave packets. However, the very low level of the observed lower hybrid turbulence is too small to impart significant energisation to the electron population.

  8. Do dividend shocks affect excess returns? An experimental study

    Directory of Open Access Journals (Sweden)

    Draganac Dragana

    2017-01-01

    Full Text Available The dividend announcement of a company is an informational event that can cause underreaction, momentum, overreaction, post-dividend announcement drift, and mean reversion. It is the uncertainty surrounding dividend announcements that leads to such behavioural phenomena. Most authors consider that underreaction occurs after dividend shocks because new information about the dividend is being slowly and gradually built into the stock price. The effect of dividend shocks is often reflected in excess returns, which can last up to one year after the shock. The experiment described in this paper tests whether statistically significant excess returns are realized after a shock dividend announcement. Participants trade with the stocks of two companies, which only differ by dividend-generating stochastic process. The dividend process of Company 2 is a Merton-style jump-diffusion process (consisting of two parts: Brownian motion and Poisson jump, while the dividend process of Company 1 contains only the Brownian motion component. Statistically significant excess returns are expected when trading with Company 2 stocks. An autoregressive model is applied in order to test this hypothesis. The conclusion is that a dividend shock is followed by statistically significant excess returns in 20 of the 22 experiments, which implies that markets are inefficient after sudden and large changes in dividends. Underreaction and discount rate effects are identified.

  9. Lower hybrid waves at the shock front: a reassessment

    Directory of Open Access Journals (Sweden)

    S. N. Walker

    2008-03-01

    Full Text Available The primary process occurring at a collisionless shock is the redistribution of the bulk upstream energy into other degrees of freedom. One part of this process results in the acceleration of electrons at the shock front. Accelerated electrons are observed at the terrestrial and other planetary shocks, comets, and their effects are observed in astrophysical phenomena such as supernova remnants and jets in the form of X-ray bremsstrahlung radiation. One of the physical models for electron acceleration at supercritical shocks is based on low-hybrid turbulence due to the presence of reflected ions in the foot region. Since lower hybrid waves propagate almost perpendicular to the magnetic field they can be simultaneously in resonance with both the unmagnetised ions (ω=Vik and magnetised electrons (ω=Vek||. In this paper, Cluster observations of the electric field are used to study the occurrence of lower hybrid waves in the front of the terrestrial bow shock. It is shown that the lower hybrid waves exist as isolated wave packets. However, the very low level of the observed lower hybrid turbulence is too small to impart significant energisation to the electron population.

  10. Simulations of Shock Wave Interaction with a Particle Cloud

    Science.gov (United States)

    Koneru, Rahul; Rollin, Bertrand; Ouellet, Frederick; Annamalai, Subramanian; Balachandar, S.'Bala'

    2016-11-01

    Simulations of a shock wave interacting with a cloud of particles are performed in an attempt to understand similar phenomena observed in dispersal of solid particles under such extreme environment as an explosion. We conduct numerical experiments in which a particle curtain fills only 87% of the shock tube from bottom to top. As such, the particle curtain upon interaction with the shock wave is expected to experience Kelvin-Helmholtz (KH) and Richtmyer-Meshkov (RM) instabilities. In this study, the initial volume fraction profile matches with that of Sandia Multiphase Shock Tube experiments, and the shock Mach number is limited to M =1.66. In these simulations we use a Eulerian-Lagrangian approach along with state-of-the-art point-particle force and heat transfer models. Measurements of particle dispersion are made at different initial volume fractions of the particle cloud. A detailed analysis of the evolution of the particle curtain with respect to the initial conditions is presented. This work was supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science Academic Alliance Program, Contract No. DE-NA0002378.

  11. Bubble Dynamics and Shock Waves

    CERN Document Server

    2013-01-01

    This volume of the Shock Wave Science and Technology Reference Library is concerned with the interplay between bubble dynamics and shock waves. It is divided into four parts containing twelve chapters written by eminent scientists. Topics discussed include shock wave emission by laser generated bubbles (W Lauterborn, A Vogel), pulsating bubbles near boundaries (DM Leppinen, QX Wang, JR Blake), interaction of shock waves with bubble clouds (CD Ohl, SW Ohl), shock propagation in polydispersed bubbly liquids by model equations (K Ando, T Colonius, CE Brennen. T Yano, T Kanagawa,  M Watanabe, S Fujikawa) and by DNS (G Tryggvason, S Dabiri), shocks in cavitating flows (NA Adams, SJ Schmidt, CF Delale, GH Schnerr, S Pasinlioglu) together with applications involving encapsulated bubble dynamics in imaging (AA Doinikov, A Novell, JM Escoffre, A Bouakaz),  shock wave lithotripsy (P Zhong), sterilization of ships’ ballast water (A Abe, H Mimura) and bubbly flow model of volcano eruptions ((VK Kedrinskii, K Takayama...

  12. Classifying prion and prion-like phenomena.

    Science.gov (United States)

    Harbi, Djamel; Harrison, Paul M

    2014-01-01

    The universe of prion and prion-like phenomena has expanded significantly in the past several years. Here, we overview the challenges in classifying this data informatically, given that terms such as "prion-like", "prion-related" or "prion-forming" do not have a stable meaning in the scientific literature. We examine the spectrum of proteins that have been described in the literature as forming prions, and discuss how "prion" can have a range of meaning, with a strict definition being for demonstration of infection with in vitro-derived recombinant prions. We suggest that although prion/prion-like phenomena can largely be apportioned into a small number of broad groups dependent on the type of transmissibility evidence for them, as new phenomena are discovered in the coming years, a detailed ontological approach might be necessary that allows for subtle definition of different "flavors" of prion / prion-like phenomena.

  13. Conditioning and breakdown phenomena in accelerator tubes

    International Nuclear Information System (INIS)

    Skorka, S.J.

    1979-01-01

    Important breakdown mechanisms in accelerator tubes are reviewed, and discharge phenomena in NEC tubes are deduced from the surface appearance of the electrodes and insulators of a used tube. Microphotos of these surfaces are shown

  14. Canister storage building natural phenomena design loads

    International Nuclear Information System (INIS)

    Tallman, A.M.

    1996-02-01

    This document presents natural phenomena hazard (NPH) loads for use in the design and construction of the Canister Storage Building (CSB), which will be located in the 200 East Area of the Hanford Site

  15. Didactic demonstrations of superfluidity and superconductivity phenomena

    International Nuclear Information System (INIS)

    Aniola-Jedrzejak, L.; Lewicki, A.; Pilipowicz, A.; Tarnawski, Z.; Bialek, H.

    1980-01-01

    In order to demonstrate to students phenomena of superfluidity and superconductivity a special helium cryostat has been constructed. The demonstrated effects, construction of the cryostat and the method of demonstration are described. (author)

  16. Ecological Understanding 1: Ways of Experiencing Photosynthesis.

    Science.gov (United States)

    Carlsson, Britta

    2002-01-01

    Investigates 10 student teachers' understanding of the different ways in which the function of the ecosystem could be experienced. Explores the functional aspects of the ecosystem using a system approach. Concludes that the idea of transformation is crucial to more complex ways of understanding photosynthesis. (Contains 62 references.) (Author/YDS)

  17. Experienced teachers' informal learning from classroom teaching

    NARCIS (Netherlands)

    Hoekstra, A.; Beijaard, D.; Brekelmans, M.; Korthagen, F.

    2007-01-01

    The purpose of this paper is to explore how experienced teachers learn informally, and more specifically, how they learn through the activities they undertake when teaching classes. Regarding these activities we studied four aspects: behaviour, cognition, motivation and emotion. During one year,

  18. Preparing Experienced Elementary Teachers as Mathematics Specialists

    Science.gov (United States)

    Nickerson, Susan D.

    2010-01-01

    High quality teaching is critical to student learning, yet takes considerable time to develop in particular content areas. Students in high-poverty, urban settings are less likely to encounter experienced and trained teachers. Administrators from a large school district and university mathematics education faculty partnered and attempted to…

  19. Novice and experienced teachers’ views on professionalism

    NARCIS (Netherlands)

    Okas, Anne; van der Schaaf, Marieke; Krull, Edgar

    2014-01-01

    This article discusses teachers’ practical knowledge and beliefs of their profession based on reflective writings of twenty Estonian teachers.Ten novice and ten experienced teachers participated in the study. They put together their professional portfolios, which among other documents included

  20. On value differences experienced by sector switchers

    NARCIS (Netherlands)

    de Graaf, G.; van der Wal, Z.

    2008-01-01

    This article examines experienced differences in values between employees in the public and private sector. To elucidate them, the authors interviewed 30 employees of the public sector previously employed in the private sector and 30 employees of the private sector previously employed in the public

  1. Experienced Teachers' Informal Learning from Classroom Teaching

    Science.gov (United States)

    Hoekstra, Annemarieke; Beijaard, Douwe; Brekelmans, Mieke; Korthagen, Fred

    2007-01-01

    The purpose of this paper is to explore how experienced teachers learn informally, and more specifically, how they learn through the activities they undertake when teaching classes. Regarding these activities we studied four aspects: behaviour, cognition, motivation and emotion. During one year, data were collected through observations of and…

  2. Experienced discrimination in home mortgage lending

    DEFF Research Database (Denmark)

    Secchi, Davide; Seri, Raffaello

    2017-01-01

    This article proposes a framework for the analysis of experienced discrimination in home mortgages. It addresses the problem of home mortgage lending discrimination in one of the richest areas of northern Italy. Employees of a local hospital were interviewed to study their perception (or experien...

  3. Transport phenomena an introduction to advanced topics

    CERN Document Server

    Glasgow, Larry A

    2010-01-01

    Enables readers to apply transport phenomena principles to solve advanced problems in all areas of engineering and science This book helps readers elevate their understanding of, and their ability to apply, transport phenomena by introducing a broad range of advanced topics as well as analytical and numerical solution techniques. Readers gain the ability to solve complex problems generally not addressed in undergraduate-level courses, including nonlinear, multidimensional transport, and transient molecular and convective transport scenarios. Avoiding rote memorization, the author em

  4. Evidence on Dropout Phenomena at Universities

    DEFF Research Database (Denmark)

    Larsen, Malene Rode; Sommersel, Hanna Bjørnøy; Larsen, Michael Søgaard

    This publication is an excerpt from the full technical report ‘Dropout Phenomena at Universities: What is Dropout? Why does Dropout Occur? What Can be Done by the Universities to Prevent or Reduce it? A systematic review’, which was completed in April 2013. The purpose of this excerpt is to present...... the knowledge we have on dropout phenomena at European universities in a short, precise and comprehensible form to allow readers to orient themselves on the subject in a more readable manner....

  5. Polarization phenomena in two body systems

    International Nuclear Information System (INIS)

    Thomas, G.H.

    1978-01-01

    A review is given of strong interactions at very low, low, intermediate, and high energies over the range 6.14 MeV to 150 GeV/c with regard to polarization phenomena in two-body systems. From the one-pion-exchange model to the theory that can possibly relate to all the phenomena, namely, quantum electrodynamics the review pointed to a unified explanation for the interactions under study. 46 references

  6. Adjustable Shock Absorbers

    OpenAIRE

    Adamiec, Radek

    2012-01-01

    Bakalářská práce obsahuje přehled používaných tlumičů osobních automobilů, závodních automobilů a motocyklů. Jsou zde popsány systémy t lumením, konstrukce tlumičů a vidlic používaných u motocyklů. Dále je zde přehled prvků používaných u podvozků automobilů. This bachelor´s thesis contains the survey of the shock absorbers of passenger cars, racing cars and motorcycles. Are described damping systems, the design used shock absorbers and forks for motorcycles. Then there is the list of the e...

  7. Radiative relativistic shock adiabate

    International Nuclear Information System (INIS)

    Tsintsadze, L.N.; Nishikawa, K.

    1997-01-01

    The influences of thermal radiation on the state equation of shock waves, derived in the previous paper [L. N. Tsintsadze, Phys. Plasmas 2, 4462 (1995)], are studied and a series of relations of thermodynamic quantities that hold for shock waves are derived. It is shown that the presence of radiation can strongly change the compressibility of the plasma. It is well known that for polytropic gases the compressibility cannot change more than four times the initial value in the case of nonrelativistic temperatures. The numerical calculations show that there are no such restrictions, when the radiation energy exceeds the kinetic energy of the plasma. The ultrarelativistic temperature range is also covered in our numerical calculations. Also studied are the influences of the radiation on the PT and the TV diagrams. A significant modification due to radiation is found in every case studied. copyright 1997 American Institute of Physics

  8. POSTURAL SHOCK IN PREGNANCY

    Science.gov (United States)

    Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

    1955-01-01

    Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

  9. Second DOE natural phenomena hazards mitigation conference

    International Nuclear Information System (INIS)

    1989-01-01

    This conference has been organized into ten presentation sessions which include an overview of the DOE Natural Phenomena Guidelines, Seismic Analysis, Seismic Design, Modifying Existing Facilities, DOE Orders, Codes, and Standards (2 sessions), Seismic Hazard (2 sessions), and Probabilistic Risk Assessment (2 sessions). Two poster sessions were also included in the program to provide a different forum for communication of ideas. Over the past fourteen years, Lawrence Livermore National Laboratory, Nuclear Systems Safety Program, has been working with the US Department of Energy, Office of Safety Appraisals and their predecessors in the area of natural phenomena hazards. During this time we have developed seismic, extreme wind/tornado, and flood hazard models for DOE sites in the United States. Guidelines for designing and evaluating DOE facilities for natural phenomena have been developed and are in interim use throughout the DOE community. A series of state-of-the practice manuals have also been developed to aid the designers. All of this material is listed in the Natural Phenomena Hazards Bibliography included in these proceedings. This conference provides a mechanism to disseminate current information on natural phenomena hazards and their mitigation. It provides an opportunity to bring together members of the DOE community to discuss current projects, to share information, and to hear practicing members of the structural engineering community discuss their experiences from past natural phenomena, future trends, and any changes to building codes. Each paper or poster presented is included in these proceedings. We have also included material related to the luncheon and dinner talks

  10. Shock Isolation Elements Testing for High Input Loadings. Volume III. Mechanical Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*SPRINGS, (*SHOCK(MECHANICS), REDUCTION), TORSION BARS, ELASTOMERS, DAMPING, EQUATIONS OF MOTION, MODEL TESTS, TEST METHODS, NUCLEAR EXPLOSIONS, HARDENING.

  11. Shock resistance testing

    International Nuclear Information System (INIS)

    Pouard, M.

    1984-03-01

    In the framework of mechanical tests and to answer the different requests for tests, the T.C.R (Transport Conditionnement et Retraitement) laboratory got test facilities. These installations allow to carry out tests of resistance to shocks, mainly at the safety level of components of nuclear power plants, mockups of transport casks for fuel elements and transport containers for radioactive materials. They include a tower and a catapult. This paper give a decription of the facilities and explain their operation way [fr

  12. On Modeling Risk Shocks

    OpenAIRE

    Dorofeenko, Victor; Lee, Gabriel; Salyer, Kevin; Strobel, Johannes

    2016-01-01

    Within the context of a financial accelerator model, we model time-varying uncertainty (i.e. risk shocks) through the use of a mixture Normal model with time variation in the weights applied to the underlying distributions characterizing entrepreneur productivity. Specifically, we model capital producers (i.e. the entrepreneurs) as either low-risk (relatively small second moment for productivity) and high-risk (relatively large second moment for productivity) and the fraction of both types is...

  13. The Shock Doctrine

    OpenAIRE

    Dionysios K. Solomos; Dimitrios N. Koumparoulis

    2011-01-01

    Naomi Klein attempts to redefine the economic history discovering the historical continuities and to reveal the neoliberal theory which functions via the utilization of specific “tools”. The state of shock is the key for the opponents of Chicago School and Milton Friedman in order for them to establish neoliberal policies and to promote the deregulated capitalism which includes less welfare state, less public sector, less regulation, weakened labor unions, privatizations and laissez-faire. Th...

  14. Shock-induced electrical activity in polymeric solids. A mechanically induced bond scission model

    International Nuclear Information System (INIS)

    Graham, R.A.

    1979-01-01

    When polymeric solids are subjected to high-pressure shock loading, two anomalous electrical phenomena, shock-induced conduction and shock-induced polarization, are observed. The present paper proposes a model of mechanically induced bond scission within the shock front to account for the effects. An experimental study of shock-induced polarization in poly(pyromellitimide) (Vespel SP-1) is reported for shock compressions from 17 to 23% (pressures from 2.5 to 5.4 GPa). Poly(pyromellitimide) is found to be a strong generator of such polarization and the polarization is found to reflect an irreversible or highly hysteretic process. The present measurements are combined with prior measurements to establish a correlation between monomer structure and strength of shock-induced polarization; feeble signals are observed in the simpler monomer repeat units of poly(tetrafluoroethylene) and polyethylene while the strongest signals are observed in more complex monomers of poly(methyl methacrylate) and poly(pyromellitimide). It is also noted that there is an apparent correlation between shock-induced conduction and shock-induced polarization. Such shock-induced electrical activity is also found to be well correlated with the propensity for mechanical bond scission observed in experiments carried out in conventional mechanochemical studies. The bond scission model can account for characteristics observed for electrical activity in shock-loaded polymers and their correlation to monomer structure. Localization of elastic energy within the monomer repeat unit or along the main chain leads to the different propensities for bond scission and resulting shock-induced electrical activity

  15. Characterization of shocked beryllium

    Directory of Open Access Journals (Sweden)

    Papin P.A.

    2012-08-01

    Full Text Available While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. In the current work, high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. Two constitutive strength (plasticity models, the Preston-Tonks-Wallace (PTW and Mechanical Threshold Stress (MTS models, were calibrated using common quasi-static and Hopkinson bar data. However, simulations with the two models give noticeably different results when compared with the measured experimental wave profiles. The experimental results indicate that, even if fractured by the initial shock loading, the Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading. Additional “arrested” drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

  16. Bubbles with shock waves and ultrasound: a review.

    Science.gov (United States)

    Ohl, Siew-Wan; Klaseboer, Evert; Khoo, Boo Cheong

    2015-10-06

    The study of the interaction of bubbles with shock waves and ultrasound is sometimes termed 'acoustic cavitation'. It is of importance in many biomedical applications where sound waves are applied. The use of shock waves and ultrasound in medical treatments is appealing because of their non-invasiveness. In this review, we present a variety of acoustics-bubble interactions, with a focus on shock wave-bubble interaction and bubble cloud phenomena. The dynamics of a single spherically oscillating bubble is rather well understood. However, when there is a nearby surface, the bubble often collapses non-spherically with a high-speed jet. The direction of the jet depends on the 'resistance' of the boundary: the bubble jets towards a rigid boundary, splits up near an elastic boundary, and jets away from a free surface. The presence of a shock wave complicates the bubble dynamics further. We shall discuss both experimental studies using high-speed photography and numerical simulations involving shock wave-bubble interaction. In biomedical applications, instead of a single bubble, often clouds of bubbles appear (consisting of many individual bubbles). The dynamics of such a bubble cloud is even more complex. We shall show some of the phenomena observed in a high-intensity focused ultrasound (HIFU) field. The nonlinear nature of the sound field and the complex inter-bubble interaction in a cloud present challenges to a comprehensive understanding of the physics of the bubble cloud in HIFU. We conclude the article with some comments on the challenges ahead.

  17. Selfsimilar time dependent shock structures

    International Nuclear Information System (INIS)

    Beck, R.; Drury, L.O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The same argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions

  18. Selfsimilar time dependent shock structures

    Science.gov (United States)

    Beck, R.; Drury, L. O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The ame argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions.

  19. Flow features that arise due to the interaction of a plane shock wave with concave profiles

    CSIR Research Space (South Africa)

    MacLucas, David A

    2012-10-01

    Full Text Available The focus of the author's thesis was the aerodynamic flow field that develops as a result of the interaction of a moving plane shock wave with concave profiles. In this presentation, he discusses some of the interesting flow phenomena that arise...

  20. A computational method for oleo-acoustics, application to hydraulic shock absorbers

    NARCIS (Netherlands)

    B. Koren (Barry); P.F.M. Michielsen (Paul); J.-W. Kars; P. Wesseling

    1995-01-01

    textabstractTo predict high-frequency oil-flow phenomena in hydraulic-shock-absorber designs, a mathematical-physical model is proposed. The model consists of the 2-D unsteady Euler equations in axial-symmetric coordinates and an appropriate equation of state for oil. The main topic of the paper is

  1. Systems, Shocks and Time Bombs

    Science.gov (United States)

    Winder, Nick

    The following sections are included: * Introduction * Modelling strategies * Are time-bomb phenomena important? * Heuristic approaches to time-bomb phenomena * Three rational approaches to TBP * Two irrational approaches * Conclusions * References

  2. Experimental Studies of Shock Interaction Phenomena Associated with Hypersonic Airbreathing Propulsion

    National Research Council Canada - National Science Library

    Holden, Michael

    2001-01-01

    ... and double cone configurations in hypersonic flow. In the best Navier-Stokes solutions the structure and density of the flowfield was captured exactly over both the hollow cylinder/flare and double cone models...

  3. Experimental Studies of Shock Interaction Phenomena Associated with Hypersonic Airbreathing Propulsion

    National Research Council Canada - National Science Library

    Holden, Michael

    2001-01-01

    Experimental studies were conducted in conjunction with computations in a code validation exercise to examine the ability of DSMC and Navier-Stokes techniques to predict the complex characteristics...

  4. Religious Fundamentalism/Religious Modernism: Conceptual Adversaries or Ambivalent Phenomena?

    Directory of Open Access Journals (Sweden)

    D. GOLOVUSHKIN

    2015-02-01

    Full Text Available Both religious modernism and religious fundamentalism appeared as problems in academic and theological literature at the beginning of the 20th century. They came about as the result of the dynamic development of modernistic ideology in Russia, the United States, Western Europe and the Islamic world. Today, the concepts of religious modernism and religious fundamentalism are widely used to describe religious processes and phenomena which are the result of interaction between religion (as a dynamic spiritual and social subsystem and society - as a social system experiencing evolution. The concept of religious modernism is traditionally associated with religious renewal, the contemporary world, and innovation. Fundamentalism, on the contrary, is an ideological commitment to the “roots and origins” of religion. Under the aegis of fundamentalism, any religious idea, value or concept has a right to exist. Religious Studies, during the course of time and the production of ever new material, encountered a serious theoretic-methodological problem: How can various religious movements and religious traditions be organized into groups since some of them combine elements of religious modernism and of religious fundamentalism? Already at the end of the nineteen-eighties, the well-established view defining “fundamentalism-modernism” as contrary positions had to be rethought. Studies dating from the nineteen-nineties and the beginning of the new millennium concentrated on noting the social origins and the political character of these phenomena. They demonstrated that neither fundamentalism nor modernism present the whole picture. The lines dividing them are so blurred, that they become confl uent. Consequently, the author concludes that religious fundamentalism and religious modernism are ambivalent phenomena, which can, on occasion, interact with each other.

  5. Geochemical modelling: what phenomena are missing

    International Nuclear Information System (INIS)

    Jacquier, P.

    1989-12-01

    In the framework of safety assessment of radioactive waste disposal, retention phenomena are usually taken into account by the Kd concept. It is well recognized that this concept is not enough for safety assessment models, because of the several and strong assumptions which are involved in this kind of representation. One way to have a better representation of the retention phenomena, is to substitute for this Kd concept an explicit description of geochemical phenomena and then couple transport codes with geochemical codes in a fully or a two-step procedure. We use currently such codes, but the scope of this paper is to display the limits today of the geochemical modelling in connection with sites analysis for deep disposal. In this paper, we intend to give an overview of phenomena which are missing in the geochemical models, or which are not completely introduced in the models. We can distinguish, on one hand phenomena for which modelling concepts exist such as adsorption/desorption and, on the other hand, phenomena for which modelling concepts do not exist for the moment such as colloids, and complexation by polyelectrolyte solutions (organics). Moreover we have to take care of very low concentrations of radionuclides, which can be expected from the leaching processes in the repository. Under those conditions, some reactions may not occur. After a critical review of the involved phenomena, we intend to stress the main directions of the wishful evolution of the geochemical modelling. This evolution should improve substantially the quality of the above-mentioned site assessments

  6. Deprivation as un-experienced harm?

    DEFF Research Database (Denmark)

    Keerus, Külli; Gjerris, Mickey; Röcklinsberg, Helena

    2017-01-01

    Tom Regan encapsulated his principle of harm as a prima facie direct duty not to harm experiencing subjects of a life. However, his consideration of harm as deprivation, one example of which is loss of freedom, can easily be interpreted as a harm, which may not be experienced by its subject....... This creates a gap between Regan’s criterion for moral status and his account of what our duties are. However, in comparison with three basic paradigms of welfare known in nonhuman animal welfare science, Regan’s understanding coheres with a modified version of a feelings-based paradigm: not only the immediate...... feelings of satisfaction, but also future opportunities to have such feelings, must be taken into account. Such an interpretation is compatible with Regan’s understanding of harm as deprivation. The potential source of confusion, however, lies in Regan’s own possible argumentative mistakes....

  7. Comparison of the light flash phenomena observed in space and in laboratory experiments

    International Nuclear Information System (INIS)

    McNulty, P.J.; Pease, V.P.; Bond, V.P.

    1976-01-01

    Astronauts on Apollo and Skylab missions have reported observing a variety of visual phenomena when their eyes were closed and adapted to darkness. These observations were studied under controlled conditions during a number of sessions on board Apollo and Skylab spacecraft and the data available to date on these so-called light flashes is in the form of descriptions of the phenomena and frequency of occurrence. Similar visual phenomena have been demonstrated in a number of laboratories by exposing the eyes of human subjects to beams of neutrons, alphas, pions, and protons. More than one physical mechanism is involved in the laboratory and space phenomena. No direct comparison of the laboratory and space observations has been made by observers who have experienced both. However, the range of visual phenomena observed in the laboratory is consistent with the Apollo and Skylab observations. Measured detection efficiencies can be used to estimate the frequencies with which various phenomena would be observed if the subject was exposed to cosmic rays in space

  8. Sensory phenomena related to tics, obsessive-compulsive symptoms, and global functioning in Tourette syndrome.

    Science.gov (United States)

    Kano, Yukiko; Matsuda, Natsumi; Nonaka, Maiko; Fujio, Miyuki; Kuwabara, Hitoshi; Kono, Toshiaki

    2015-10-01

    Sensory phenomena, including premonitory urges, are experienced by patients with Tourette syndrome (TS) and obsessive-compulsive disorder (OCD). The goal of the present study was to investigate such phenomena related to tics, obsessive-compulsive symptoms (OCS), and global functioning in Japanese patients with TS. Forty-one patients with TS were assessed using the University of São Paulo Sensory Phenomena Scale (USP-SPS), the Premonitory Urge for Tics Scale (PUTS), the Yale Global Tic Severity Scale (YGTSS), the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS), and the Global Assessment of Functioning (GAF) Scale. USP-SPS and PUTS total scores were significantly correlated with YGTSS total and vocal tics scores. Additionally, both sensory phenomena severity scores were significantly correlated with DY-BOCS total OCS scores. Of the six dimensional OCS scores, the USP-SPS scores were significantly correlated with measures of aggression and sexual/religious dimensions. Finally, the PUTS total scores were significantly and negatively correlated with GAF scores. By assessing premonitory urges and broader sensory phenomena, and by viewing OCS from a dimensional approach, this study provides significant insight into sensory phenomena related to tics, OCS, and global functioning in patients with TS. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. The Occupational Wellbeing of People Experiencing Homelessness

    OpenAIRE

    Thomas, Yvonne; Gray, M.; McGinty, S.

    2017-01-01

    This paper reports findings of a study that utilised an occupational perspective to explore how wellbeing was achieved and sustained by the occupations of people experiencing homelessness in Australia. Thirty three in-depth qualitative interviews were conducted with homeless individuals in a regional city in Australia. Data from the interviews were thematically analysed to understand the relationship between wellbeing, as defined by the individual, and the occupations engaged in by people exp...

  10. Burnout among Low and High Experienced Teachers

    Directory of Open Access Journals (Sweden)

    Seyedehhava Mousavy

    2012-09-01

    Full Text Available Burnout is a serious psychological syndrome that can affect not only an individual’s well-being, but also the functioning of whole organisations, such as schools. It is characterized by emotional exhaustion, depersonalization, and decreased personal accomplishment.The level of burnout among teachers in the field of education has a negative impact on student success. The present investigation examines the level of burn out among high and low experienced teachers. It focused on a group of English teachers from different nationalities: Iranian, and Malaysian at UPM to examine if there is any relation between burnout and experience level. The sample consisted of 30 English teachers. Two instruments namely, The Maslach Burnout Inventory and Demographic Questionnaire were used to collect data. Data analysis revealed that there is no significant difference in depersonalization and personal accomplishment scores between low and high experienced teachers. But the result of this study also revealed that there is a significant difference in Emotional Exhaustion scores between low and high experienced teachers. Further research is required to explore the roots and the causes of burnout.

  11. Relation between total shock energy and mortality in patients with implantable cardioverter-defibrillator.

    Science.gov (United States)

    Tenma, Taro; Yokoshiki, Hisashi; Mitsuyama, Hirofumi; Watanabe, Masaya; Mizukami, Kazuya; Kamada, Rui; Takahashi, Masayuki; Sasaki, Ryo; Maeno, Motoki; Okamoto, Kaori; Chiba, Yuki; Anzai, Toshihisa

    2018-05-15

    Implantable Cardioverter-Defibrillator (ICD) shocks have been associated with mortality. However, no study has examined the relation between total shock energy and mortality. The aim of this study is to assess the association of total shock energy with mortality, and to determine the patients who are at risk of this association. Data from 316 consecutive patients who underwent initial ICD implantation in our hospital between 2000 and 2011 were retrospectively studied. We collected shock energy for 3 years from the ICD implantation, and determined the relation of shock energy on mortality after adjusting confounding factors. Eighty-seven ICD recipients experienced shock(s) within 3 years from ICD implantation and 43 patients had died during the follow-up. The amount of shock energy was significantly associated with all-cause death [adjusted hazard ratio (HR) 1.26 (per 100 joule increase), p energy accumulation (≥182 joule) was lower (p energy accumulation (energy accumulation and all-cause death was remarkable in the patients with low left ventricular ejection fraction (LVEF ≤40%) or atrial fibrillation (AF). Increase of shock energy was related to mortality in ICD recipients. This relation was evident in patients with low LVEF or AF. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. [Spiritual phenomena occurring in everybody and health].

    Science.gov (United States)

    Krsiak, M

    2008-01-01

    The past several years have seen an explosion of research in the area of spirituality and health. However, confusion and incomprehension of the conception of spirituality (e.g. confounding spirituality with various conventional views on religiousness) hampers better understanding in this area. The present paper proposes definition of spiritual phenomena in man based on natural epistemological and instrumental criteria (whether a certain phenomenon can be objectively known and evoked): spiritual phenomena in man are those, which cannot be objectively known nor evoked, but which act (e.g., love, idea). Spiritual phenomena can be really known only in the self ("in spirit"). Objectively known can be only manifestations of spiritual phenomena. Some attributes of love (e.g. its personal uniqueness) or ideas (e.g., sense of own life) whose satisfaction appears to be important for health are briefly outlined. A review of some frequently cited recent papers investigating the role of spirituality in health and discussion of frequent pitfalls in this area is given. Spirituality is a universal human phenomenon. All human beings, secular or religious, encounter with spiritual phenomena. Although the present conception of spirituality distances from some conventional views on religiousness, it is not atheistic. On the contrary, it accommodates the basic religious concept "God is love". Conceptual clarification is essential for further progress in the study of impact of spirituality on health.

  13. Risk shocks and housing markets

    OpenAIRE

    Dorofeenko, Viktor; Lee, Gabriel S.; Salyer, Kevin D.

    2010-01-01

    Abstract: This paper analyzes the role of uncertainty in a multi-sector housing model with financial frictions. We include time varying uncertainty (i.e. risk shocks) in the technology shocks that affect housing production. The analysis demonstratesthat risk shocks to the housing production sector are a quantitatively important impulse mechanism for the business cycle. Also, we demonstrate that bankruptcy costs act as an endogenous markup factor in housing prices; as a consequence, the volati...

  14. Pseudo-shock waves and their interactions in high-speed intakes

    Science.gov (United States)

    Gnani, F.; Zare-Behtash, H.; Kontis, K.

    2016-04-01

    In an air-breathing engine the flow deceleration from supersonic to subsonic conditions takes places inside the isolator through a gradual compression consisting of a series of shock waves. The wave system, referred to as a pseudo-shock wave or shock train, establishes the combustion chamber entrance conditions, and therefore influences the performance of the entire propulsion system. The characteristics of the pseudo-shock depend on a number of variables which make this flow phenomenon particularly challenging to be analysed. Difficulties in experimentally obtaining accurate flow quantities at high speeds and discrepancies of numerical approaches with measured data have been readily reported. Understanding the flow physics in the presence of the interaction of numerous shock waves with the boundary layer in internal flows is essential to developing methods and control strategies. To counteract the negative effects of shock wave/boundary layer interactions, which are responsible for the engine unstart process, multiple flow control methodologies have been proposed. Improved analytical models, advanced experimental methodologies and numerical simulations have allowed a more in-depth analysis of the flow physics. The present paper aims to bring together the main results, on the shock train structure and its associated phenomena inside isolators, studied using the aforementioned tools. Several promising flow control techniques that have more recently been applied to manipulate the shock wave/boundary layer interaction are also examined in this review.

  15. Can environmental conditions experienced in early life influence future generations?

    Science.gov (United States)

    Burton, Tim; Metcalfe, Neil B

    2014-06-22

    The consequences of early developmental conditions for performance in later life are now subjected to convergent interest from many different biological sub-disciplines. However, striking data, largely from the biomedical literature, show that environmental effects experienced even before conception can be transmissible to subsequent generations. Here, we review the growing evidence from natural systems for these cross-generational effects of early life conditions, showing that they can be generated by diverse environmental stressors, affect offspring in many ways and can be transmitted directly or indirectly by both parental lines for several generations. In doing so, we emphasize why early life might be so sensitive to the transmission of environmentally induced effects across generations. We also summarize recent theoretical advancements within the field of developmental plasticity, and discuss how parents might assemble different 'internal' and 'external' cues, even from the earliest stages of life, to instruct their investment decisions in offspring. In doing so, we provide a preliminary framework within the context of adaptive plasticity for understanding inter-generational phenomena that arise from early life conditions.

  16. PROCESS OF GLOBAL SHOCKS TRANSMISSION TO DOMESTIC FOOD PRICE LEVEL: CASE OF BANGLADESH

    Directory of Open Access Journals (Sweden)

    Fakir Azmal Huda

    2014-04-01

    Full Text Available The world experienced in dramatic price surge of food commodities since mid of 2007 to 2008. It was claimed that the crisis were being mainly for backdrop of global shocks in food and energy price. But how the shocks come to domestic market from external sources is a researchable phenomenon. Surprisingly few attempts have been made to systematically analysis of shock transmission from international to domestic market. The study analyzed the effect of global commodity market factors and domestic exchange rate development on domestic food price in Bangladesh. A bi-variants co-integration approach was applied for the analysis of shock transmission. Finally an error correction model was developed. The overall magnitudes of the pass through suggest that only 46 per cent of the total world shock pass-through in domestic economy.

  17. Fetus, fasting, and festival: the persistent effects of in utero social shocks.

    Science.gov (United States)

    Chen, Xi

    2014-09-01

    The Fetal Origins Hypothesis (FOH), put forward in the epidemiological literature and later flourished in the economics literature, suggests that the time in utero is a critical period for human development. However, much attention has been paid to the consequences of fetal exposures to more extreme natural shocks, while less is known about fetal exposures to milder but more commonly experienced social shocks. Using two examples of under-nutrition due to mild social shocks, i.e. Ramadan fasting and festival overspending, this paper summarizes our current knowledge, especially the contribution from economics, and key challenges in exploring fetal exposures to milder social shocks. I also discuss the salient added value of identifying milder versus more extreme fetal shocks. Finally, implications are drawn on individual decisions and public policy to improve children's well-being before they are born or even before their mothers realize that they are pregnant.

  18. Fetus, Fasting, and Festival: The Persistent Effects of In Utero Social Shocks

    Directory of Open Access Journals (Sweden)

    Xi Chen

    2014-09-01

    Full Text Available The Fetal Origins Hypothesis (FOH, put forward in the epidemiological literature and later flourished in the economics literature, suggests that the time in utero is a critical period for human development. However, much attention has been paid to the consequences of fetal exposures to more extreme natural shocks, while less is known about fetal exposures to milder but more commonly experienced social shocks. Using two examples of under-nutrition due to mild social shocks, i.e. Ramadan fasting and festival overspending, this paper summarizes our current knowledge, especially the contribution from economics, and key challenges in exploring fetal exposures to milder social shocks. I also discuss the salient added value of identifying milder versus more extreme fetal shocks. Finally, implications are drawn on individual decisions and public policy to improve children’s well-being before they are born or even before their mothers realize that they are pregnant.

  19. Health shocks and risk aversion.

    Science.gov (United States)

    Decker, Simon; Schmitz, Hendrik

    2016-12-01

    We empirically assess whether a health shock influences individual risk aversion. We use grip strength data to obtain an objective health shock indicator. In order to account for the non-random nature of our data regression-adjusted matching is employed. Risk preferences are traditionally assumed to be constant. However, we find that a health shock increases individual risk aversion. The finding is robust to a series of sensitivity analyses and persists for at least four years after the shock. Income changes do not seem to be the driving mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Shock in the emergency department

    DEFF Research Database (Denmark)

    Holler, Jon Gitz; Henriksen, Daniel Pilsgaard; Mikkelsen, Søren

    2016-01-01

    BACKGROUND: The knowledge of the frequency and associated mortality of shock in the emergency department (ED) is limited. The aim of this study was to describe the incidence, all-cause mortality and factors associated with death among patients suffering shock in the ED. METHODS: Population...... failures. Outcomes were annual incidence per 100,000 person-years at risk (pyar), all-cause mortality at 0-7, and 8-90 days and risk factors associated with death. RESULTS: We identified 1646 of 438,191 (0.4 %) ED patients with shock at arrival. Incidence of shock increased from 53.8 to 80.6 cases per 100...

  1. Shock compression of diamond crystal

    OpenAIRE

    Kondo, Ken-ichi; Ahrens, Thomas J.

    1983-01-01

    Two shock wave experiments employing inclined mirrors have been carried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9 ± 0.3 mm/µsec and an amplitude of 63 ± 28 GPa. An alternate interpretation of the inclined wedge mirror streak record suggests a ramp precursor wave and th...

  2. The making of extraordinary psychological phenomena.

    Science.gov (United States)

    Lamont, Peter

    2012-01-01

    This article considers the extraordinary phenomena that have been central to unorthodox areas of psychological knowledge. It shows how even the agreed facts relating to mesmerism, spiritualism, psychical research, and parapsychology have been framed as evidence both for and against the reality of the phenomena. It argues that these disputes can be seen as a means through which beliefs have been formulated and maintained in the face of potentially challenging evidence. It also shows how these disputes appealed to different forms of expertise, and that both sides appealed to belief in various ways as part of the ongoing dispute about both the facts and expertise. Finally, it shows how, when a formal Psychology of paranormal belief emerged in the twentieth century, it took two different forms, each reflecting one side of the ongoing dispute about the reality of the phenomena. © 2012 Wiley Periodicals, Inc.

  3. A Shocking Solar Nebula?

    OpenAIRE

    Liffman, Kurt

    2009-01-01

    It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

  4. Myths of "shock therapy".

    Science.gov (United States)

    Fink, M

    1977-09-01

    The author discusses the myths of the ECT process--that shock and the convulsion are essential, memory loss and brain damage are inescapable, and little is known of the process--and assesses the fallacies in these ideas. Present views of the ECT process suggest that its mode of action in depression may best be described as a prolonged form of diencephalic stimulation, particularly useful to affect the hypothalamic dysfunctions that characterize depressive illness. The author emphasizes the need for further study of this treatment modality and for self-regulation by the profession.

  5. Study on in-vessel thermohydraulics phenomena of sodium-cooled fast reactors. 3. Numerical investigation for thermal stratification phenomena in the upper plenum

    International Nuclear Information System (INIS)

    Muramatsu, Toshiharu; Yamaguchi, Akira

    2002-06-01

    A large-scale sodium-cooled fast breeder reactor in the feasibility studies on commercialized fast reactors has a feature of consideration of thorough simplified and compacted systems and components design to realize drastic economical improvements. Therefore, special attentions should be paid to thermohydraulic designs for gas entrainment behavior from free surface, flow-induced vibration of in-vessel components, thermal stratification in the plenum, thermal shock for various structures due to high-speed coolant flows, nonsymmetrical coolant flows, etc. in the reactor vessel. In-vessel thermohydraulic analyses were carried out using a multi-dimensional code AQUA to understand the thermal stratification characteristics in the upper plenum, and to investigate trade-off relations between gas entrainment and thermal stratification phenomena on in-vessel structures for the elimination of gas entrainment possibility. From the analysis, the following results were obtained. (1) Dummy plug insertion to a slit of the upper core structure is one of the effective measures to stabilize the in-vessel flow patterns and to mitigate in-vessel thermal shocks. (2) Though flow guide device such as a baffle ring attached to reactor vessel wall is an effective measure to eliminate impinging jet to dipped plate, rising characteristics of the thermal stratification interface are affected by the baffle ring devise. (3) Thermal stratification characteristics are not influenced very much by the installation of a partial inner barrel to the dipped plate, which is an effective measure to reduce the horizontal flow velocity components at free surface. (4) Labyrinth structures to the gap between the reactor vessel wall and the outer dipped plate have direct effects upon in-vessel thermal shock characteristics including thermal stratification phenomena due to the closing of flow path between the upper plenum and the free surface plenum. (author)

  6. Self field electromagnetism and quantum phenomena

    Science.gov (United States)

    Schatten, Kenneth H.

    1994-07-01

    Quantum Electrodynamics (QED) has been extremely successful inits predictive capability for atomic phenomena. Thus the greatest hope for any alternative view is solely to mimic the predictive capability of quantum mechanics (QM), and perhaps its usefulness will lie in gaining a better understanding of microscopic phenomena. Many ?paradoxes? and problematic situations emerge in QED. To combat the QED problems, the field of Stochastics Electrodynamics (SE) emerged, wherein a random ?zero point radiation? is assumed to fill all of space in an attmept to explain quantum phenomena, without some of the paradoxical concerns. SE, however, has greater failings. One is that the electromagnetic field energy must be infinit eto work. We have examined a deterministic side branch of SE, ?self field? electrodynamics, which may overcome the probelms of SE. Self field electrodynamics (SFE) utilizes the chaotic nature of electromagnetic emissions, as charges lose energy near atomic dimensions, to try to understand and mimic quantum phenomena. These fields and charges can ?interact with themselves? in a non-linear fashion, and may thereby explain many quantum phenomena from a semi-classical viewpoint. Referred to as self fields, they have gone by other names in the literature: ?evanesccent radiation?, ?virtual photons?, and ?vacuum fluctuations?. Using self fields, we discuss the uncertainty principles, the Casimir effects, and the black-body radiation spectrum, diffraction and interference effects, Schrodinger's equation, Planck's constant, and the nature of the electron and how they might be understood in the present framework. No new theory could ever replace QED. The self field view (if correct) would, at best, only serve to provide some understanding of the processes by which strange quantum phenomena occur at the atomic level. We discuss possible areas where experiments might be employed to test SFE, and areas where future work may lie.

  7. Experimental search for compression phenomena in fast nucleus--nucleus collisions

    International Nuclear Information System (INIS)

    Schopper, E.; Baumgardt, H.G.; Obst, E.

    1977-01-01

    The occurrence of compression phenomena and shock waves, connected with the increase of the density of the nuclear matter during the interpenetration of two fast nuclei, are discussed. Current experiments dealing with this problem are reviewed. Before considering the mechanism of the interpenetration of two fast nuclei it may be useful to look at more simple situations, i.e., proton-proton interactions, then to envelop them with nuclear matter, considering proton-nucleus interactions. Only very general features are described, which may give suggestions for the understanding of the nucleus-nucleus impact

  8. Discrete Particle Method for Simulating Hypervelocity Impact Phenomena

    Directory of Open Access Journals (Sweden)

    Erkai Watson

    2017-04-01

    Full Text Available In this paper, we introduce a computational model for the simulation of hypervelocity impact (HVI phenomena which is based on the Discrete Element Method (DEM. Our paper constitutes the first application of DEM to the modeling and simulating of impact events for velocities beyond 5 kms-1. We present here the results of a systematic numerical study on HVI of solids. For modeling the solids, we use discrete spherical particles that interact with each other via potentials. In our numerical investigations we are particularly interested in the dynamics of material fragmentation upon impact. We model a typical HVI experiment configuration where a sphere strikes a thin plate and investigate the properties of the resulting debris cloud. We provide a quantitative computational analysis of the resulting debris cloud caused by impact and a comprehensive parameter study by varying key parameters of our model. We compare our findings from the simulations with recent HVI experiments performed at our institute. Our findings are that the DEM method leads to very stable, energy–conserving simulations of HVI scenarios that map the experimental setup where a sphere strikes a thin plate at hypervelocity speed. Our chosen interaction model works particularly well in the velocity range where the local stresses caused by impact shock waves markedly exceed the ultimate material strength.

  9. Gravitational shock waves and extreme magnetomaterial shock waves

    International Nuclear Information System (INIS)

    Lichnerowicz, Andre.

    1975-01-01

    Within an astrophysical context corresponding to high densities, a self-gravitating model is studied, which is the set of an extreme material medium of infinite conductivity and of a magnetic field. Corresponding shock waves generate necessarily, in general, gravitational shock waves [fr

  10. Shock Producers and Shock Absorbers in the Crisis

    OpenAIRE

    Sinn, Hans-Werner

    2009-01-01

    It is not surprising that the U.S. has been by far the world’s largest shock producer in this crisis. The big shock absorbers on the other hand were Japan, Russia and Germany, whose exports shrank more than their imports.

  11. Simulations of Converging Shock Collisions for Shock Ignition

    Science.gov (United States)

    Sauppe, Joshua; Dodd, Evan; Loomis, Eric

    2016-10-01

    Shock ignition (SI) has been proposed as an alternative to achieving high gain in inertial confinement fusion (ICF) targets. A central hot spot below the ignition threshold is created by an initial compression pulse, and a second laser pulse drives a strong converging shock into the fuel. The collision between the rebounding shock from the compression pulse and the converging shock results in amplification of the converging shock and increases the hot spot pressure above the ignition threshold. We investigate shock collision in SI drive schemes for cylindrical targets with a polystyrene foam interior using radiation-hydrodynamics simulations with the RAGE code. The configuration is similar to previous targets fielded on the Omega laser. The CH interior results in a lower convergence ratio and the cylindrical geometry facilitates visualization of the shock transit using an axial X-ray backlighter, both of which are important for comparison to potential experimental measurements. One-dimensional simulations are used to determine shock timing, and the effects of low mode asymmetries in 2D computations are also quantified. LA-UR-16-24773.

  12. Separation phenomena in Liquids and Gases

    Energy Technology Data Exchange (ETDEWEB)

    Louvet, P; Soubbaramayer, [CEA Saclay, Dept. des Lasers et de la Physico-Chimie, DESICP/DLPC/SPP, 91 - Gif-sur-Yvette (France); Noe, P

    1989-07-01

    technology was up to the task but the programme was shelved mainly because of lack of demand. Finally, seven papers deal with laser processes. Two of them review the AVLIS program in the UK and one paper gives the status of the MLIS project in West Germany. One communication from China and three papers by French authors deal with specific problems currently met in AVLIS studies, on the vapour beam and the ion extraction. A number of phenomena observed in AVLIS needs satisfactory explanations: the high value of the vapour velocity, the low value of metastables in the vapour beam, the extraction of ions at high density, etc. Session 1: plasma separation (review of isotopic plasma separation processes; production of depleted zirconium using a plasma centrifuge; measurements of isotope separation in a vacuum arc centrifuge). Session 2: plasma separation and centrifugation (recent developments in stable isotope separation by ionic cyclotron resonance; some aspects of the separation of multi-isotope mixtures with gas centrifuges; review paper on centrifuge technology and status of the URENCO centrifuge project; solution of the two-fluid equations for flow in a centrifuge; influence of stationary poles in the central region of gas centrifuges; extension of the analytic sixth order theory; applications of different analytic solutions for the centrifuge flow). Sessions 4 and 5: rotating flows (convection flows driven by centrifugal buoyancy in rapidly rotating systems; experimental investigation of the flow in a rotating pie-shaped cylinder; temperature distribution on rotating spherical shells; centrifugal separation of a suspension in a rotating vessel; spin-up from rest of a suspension - preliminary insight). Session 6: particle fluid mixture (modelling, simulation and comprehension of the flow field of a particles-fluid mixture; the effect of shear and lift on particle-gas separation; on the hydrodynamics of electrolytic refining of metals). Session 7 (calculation of condensation

  13. Separation phenomena in Liquids and Gases

    International Nuclear Information System (INIS)

    Louvet, P.; Dr Soubbaramayer; Noe, P.

    1989-01-01

    technology was up to the task but the programme was shelved mainly because of lack of demand. Finally, seven papers deal with laser processes. Two of them review the AVLIS program in the UK and one paper gives the status of the MLIS project in West Germany. One communication from China and three papers by French authors deal with specific problems currently met in AVLIS studies, on the vapour beam and the ion extraction. A number of phenomena observed in AVLIS needs satisfactory explanations: the high value of the vapour velocity, the low value of metastables in the vapour beam, the extraction of ions at high density, etc. Session 1: plasma separation (review of isotopic plasma separation processes; production of depleted zirconium using a plasma centrifuge; measurements of isotope separation in a vacuum arc centrifuge). Session 2: plasma separation and centrifugation (recent developments in stable isotope separation by ionic cyclotron resonance; some aspects of the separation of multi-isotope mixtures with gas centrifuges; review paper on centrifuge technology and status of the URENCO centrifuge project; solution of the two-fluid equations for flow in a centrifuge; influence of stationary poles in the central region of gas centrifuges; extension of the analytic sixth order theory; applications of different analytic solutions for the centrifuge flow). Sessions 4 and 5: rotating flows (convection flows driven by centrifugal buoyancy in rapidly rotating systems; experimental investigation of the flow in a rotating pie-shaped cylinder; temperature distribution on rotating spherical shells; centrifugal separation of a suspension in a rotating vessel; spin-up from rest of a suspension - preliminary insight). Session 6: particle fluid mixture (modelling, simulation and comprehension of the flow field of a particles-fluid mixture; the effect of shear and lift on particle-gas separation; on the hydrodynamics of electrolytic refining of metals). Session 7 (calculation of condensation

  14. Vector (two-dimensional) magnetic phenomena

    International Nuclear Information System (INIS)

    Enokizono, Masato

    2002-01-01

    In this paper, some interesting phenomena were described from the viewpoint of two-dimensional magnetic property, which is reworded with the vector magnetic property. It shows imperfection of conventional magnetic property and some interested phenomena were discovered, too. We found magnetic materials had the strong nonlinearity both magnitude and spatial phase due to the relationship between the magnetic field strength H-vector and the magnetic flux density B-vector. Therefore, magnetic properties should be defined as the vector relationship. Furthermore, the new Barukhausen signal was observed under rotating flux. (Author)

  15. Incorporating interfacial phenomena in solidification models

    Science.gov (United States)

    Beckermann, Christoph; Wang, Chao Yang

    1994-01-01

    A general methodology is available for the incorporation of microscopic interfacial phenomena in macroscopic solidification models that include diffusion and convection. The method is derived from a formal averaging procedure and a multiphase approach, and relies on the presence of interfacial integrals in the macroscopic transport equations. In a wider engineering context, these techniques are not new, but their application in the analysis and modeling of solidification processes has largely been overlooked. This article describes the techniques and demonstrates their utility in two examples in which microscopic interfacial phenomena are of great importance.

  16. Arcing phenomena in fusion devices workshop

    International Nuclear Information System (INIS)

    Clausing, R.E.

    1979-01-01

    The workshop on arcing phenomena in fusion devices was organized (1) to review the pesent status of our understanding of arcing as it relates to confinement devices, (2) to determine what informaion is needed to suppress arcing and (3) to define both laboratory and in-situ experiments which can ultimately lead to reduction of impurities in the plasma caused by arcing. The workshop was attended by experts in the area of vacuum arc electrode phenomena and ion source technology, materials scientists, and both theoreticians and experimentalists engaged in assessing the importance of unipolar arcing in today's tokamaks. Abstracts for papers presented at the workshop are included

  17. Electrical breakdown phenomena of dielectric elastomers

    DEFF Research Database (Denmark)

    Mateiu, Ramona Valentina; Yu, Liyun; Skov, Anne Ladegaard

    2017-01-01

    Silicone elastomers have been heavily investigated as candidates for dielectric elastomers and are as such almost ideal candidates with their inherent softness and compliance but they suffer from low dielectric permittivity. This shortcoming has been sought optimized by many means during recent...... years. However, optimization with respect to the dielectric permittivity solely may lead to other problematic phenomena such as premature electrical breakdown. In this work, we investigate the electrical breakdown phenomena of various types of permittivity-enhanced silicone elastomers. Two types...... of silicone elastomers are investigated and different types of breakdown are discussed. Furthermore the use of voltage stabilizers in silicone-based dielectric elastomers is investigated and discussed....

  18. Dissipative phenomena in condensed matter some applications

    CERN Document Server

    Dattagupta, Sushanta

    2004-01-01

    From the field of nonequilibrium statistical physics, this graduate- and research-level volume treats the modeling and characterization of dissipative phenomena. A variety of examples from diverse disciplines like condensed matter physics, materials science, metallurgy, chemical physics etc. are discussed. Dattagupta employs the broad framework of stochastic processes and master equation techniques to obtain models for a wide range of experimentally relevant phenomena such as classical and quantum Brownian motion, spin dynamics, kinetics of phase ordering, relaxation in glasses, dissipative tunneling. It provides a pedagogical exposition of current research material and will be useful to experimentalists, computational physicists and theorists.

  19. Ordering phenomena in ABA triblock copolymer gels

    DEFF Research Database (Denmark)

    Reynders, K.; Mischenko, N.; Kleppinger, R.

    1997-01-01

    Temperature and concentration dependencies of the degree of order in ABA triblock copolymer gels are discussed. Two factors can influence the ordering phenomena: the conformation of the midblocks (links of the network) and the polydispersity of the endblock domains (nodes of the network). The lat......Temperature and concentration dependencies of the degree of order in ABA triblock copolymer gels are discussed. Two factors can influence the ordering phenomena: the conformation of the midblocks (links of the network) and the polydispersity of the endblock domains (nodes of the network...

  20. Third DOE natural phenomena hazards mitigation conference

    International Nuclear Information System (INIS)

    1991-01-01

    This conference on Natural Phenomena Hazards Mitigation has been organized into 15 presentation, panel, and poster sessions. The sessions included an overview of activities at DOE Headquarters; natural phenomena hazards tasks underway for DOE; two sessions on codes, standards, orders, criteria, and guidelines; two sessions on seismic hazards; equipment qualification; wind; PRA and margin assessments; modifications, retrofit, and restart; underground structures with a panel discussion; seismic analysis; seismic evaluation and design; and a poster session. Individual projects are processed separately for the data bases

  1. Ethical Conflicts Experienced by Medical Students

    Directory of Open Access Journals (Sweden)

    Márcia Mendes Menezes

    Full Text Available ABSTRACT The current study aimed to identify and analyze the prevalence of ethical conflicts experienced by medical students. This study is a cross-sectional and analytical research that was conducted in a public school in the state of Minas Gerais, Brazil. The instrument used for the data collection was a self-administered questionnaire. The data collected were presented in absolute and percentage values. For the analytical statistical treatment of the data, the level of significance was considered p <0.05. The outcome variables were: Experiences of ethical conflicts in interpersonal relations within the medical course and Ethical conduct in health care. The identification of the prevalence of ethical conflicts in the undergraduate program adopted the perspective of different interpersonal relations (academic-teaching, academic-academic, academic-employee, academic-patient, teacher-teacher, teacher-patient, teacher-employee and employee-patient. (Importance of identifying themselves to the health services user and requesting consent to perform the physical examination, assistance without the supervision of the teacher, issuance of health documents without the signature of the professional responsible and use of social networks to share data Of patient. It was verified the association of the outcome variables with sex, year of graduation and course evaluation. A total of 281 undergraduate students enrolled in all undergraduate courses in Medicine of both sexes, with a predominance of female (52.7%. The students reported having experienced conflicting situations in interpersonal relations with teachers (59.6%, provided assistance without proper supervision of a teacher (62.6%, reported having issued health documents without the accompaniment of teachers (18, 5%. The highest frequency was observed among those enrolled in the most advanced years of the undergraduate program (p <0.05. The use of social networks for the purpose of sharing patient

  2. Oxygen radicals in experimental shock: effects of spin-trapping nitrones in ameliorating shock pathophysiology (see comments)

    Energy Technology Data Exchange (ETDEWEB)

    Novelli, G.P. (Institute of Anesthesiology and Intensive Care, University of Florence, Careggi Hospital, (Italy))

    1992-04-01

    Circulatory shock is accepted as a consequence of an acute oxygen radical overgeneration. Spin-trapping nitrones inactivate free radicals by forming relatively stable adducts. Three spin-trapping nitrones (N-tert-phenyl-butyl-nitrone; alpha-4-pyridyl-oxide-N-tert-butyl-nitrone; 5-5,dimethyl,1,pyrroline-N-oxide) were tested regarding their role in the pathophysiology and evolution of circulatory shock in rats. A prospective, randomized, controlled trial of spin-trapping nitrones in rats experiencing three different models of circulatory shock was designed. In the first group, endotoxic, traumatic, and mesenteric artery occlusion shock (all 100% lethal in control experiments) was prevented by the ip administration of N-tert-phenyl-butyl-nitrone (150 mg/kg); alpha-4-pyridyl-oxide-N-tert-butyl-nitrone (100 mg/kg); or 5-5,dimethyl,1,pyrroline-N-oxide (100 mg/kg). However, the evolution of shock was unaffected by the same compounds when all three nitrones had been previously inactivated by exposure to light and air. In the second group, microcirculatory derangements that were provoked by endotoxin and were observed in the mesocecum of rats were completely prevented by pretreatment with either peritoneal administration of each of the three nitrones or by their topical application to the microscopic field. While the rats survived after systemic treatment, those rats receiving topical nitrones died from endotoxic shock. In the third group, cell-membrane stiffness (a sign of peroxidative damage) was measured by spin-probes and electron-spin resonance in mitochondrial and microsomal membranes. Cell membranes obtained from shocked rats were more rigid than those membranes of controls. However, the membranes obtained from rats that were submitted to trauma or endotoxin after pretreatment with N-tert-phenyl-butyl-nitrone had normal stiffness.

  3. 30th International Symposium on Shock Waves

    CERN Document Server

    Sadot, Oren; Igra, Ozer

    2017-01-01

    These proceedings collect the papers presented at the 30th International Symposium on Shock Waves (ISSW30), which was held in Tel-Aviv Israel from July 19 to July 24, 2015. The Symposium was organized by Ortra Ltd. The ISSW30 focused on the state of knowledge of the following areas: Nozzle Flow, Supersonic and Hypersonic Flows with Shocks, Supersonic Jets, Chemical Kinetics, Chemical Reacting Flows, Detonation, Combustion, Ignition, Shock Wave Reflection and Interaction, Shock Wave Interaction with Obstacles, Shock Wave Interaction with Porous Media, Shock Wave Interaction with Granular Media, Shock Wave Interaction with Dusty Media, Plasma, Magnetohyrdrodynamics, Re-entry to Earth Atmosphere, Shock Waves in Rarefied Gases, Shock Waves in Condensed Matter (Solids and Liquids), Shock Waves in Dense Gases, Shock Wave Focusing, Richtmyer-Meshkov Instability, Shock Boundary Layer Interaction, Multiphase Flow, Blast Waves, Facilities, Flow Visualization, and Numerical Methods. The two volumes serve as a reference ...

  4. Ethical problems experienced by oncology nurses.

    Science.gov (United States)

    da Luz, Kely Regina; Vargas, Mara Ambrosina de Oliveira; Schmidtt, Pablo Henrique; Barlem, Edison Luiz Devos; Tomaschewski-Barlem, Jamila Geri; da Rosa, Luciana Martins

    2015-01-01

    To know the ethical problems experienced by oncology nurses. Descriptive and exploratory study with a qualitative approach, performed in inpatient units and in chemotherapy out-patients units that provide assistance to oncological patients in two capitals in the South region of Brazil. Eighteen nurses participated in this study, selected by snowball sampling type. For data collection, semi-structured interviews were carried out, which were recorded and transcribed, and then analyzed by thematic analysis. Two categories were established: when informing or not becomes a dilemma - showing the main difficulties related to oncological treatment information regarding health staff, health system, and infrastructure; to invest or not - dilemmas related to finitude - showing situations of dilemmas related to pain and confrontation with finitude. For the effective confrontation of the ethical problems experienced by oncology nurses to occur, it is important to invest in the training of these professionals, preparing them in an ethical and human way to act as lawyers of the patient with cancer, in a context of dilemmas related mainly to the possibility of finitude.

  5. Physics Climate as Experienced by LGBT+ Physicists

    Science.gov (United States)

    Long, Elena

    2012-02-01

    In 2009, Elena Long created the LGBT+ Physicists website (http://lgbtphysicists.x10hosting.com) as a warehouse for resources useful for sexual and gender minorities working in physics. This resource has grown to include networking resources, lists of LGBT-friendly universities and localities, recommendations for enacting positive change in physics communities, and out-reach to other STEM-oriented LGBT organizations. This has been possible in large part by the dynamic community of LGBT+ physicists and allies looking to make physics more welcoming towards our community. In 2011, Elena used hir position as Member at Large on the executive committee of the Forum of Graduate Student Affairs (FGSA) to conduct a climate survey that included, among other things, the first serious look at LGBT+ demographics in physics. The survey focused particularly on issues of language heard and harassment experienced by physicists and was broken down into categories based on race, physical and mental ability, gender, and sexuality. Furthermore, it examined the outcomes of experienced harassment and the reasons for when harassment was not reported. Due to the nature of the study, overlapping demographics, especially ``multiple minorities,'' were also explored. This talk will give a brief history of the LGBT+ Physicists resource as well as an overview of the FGSA study.

  6. Molecular diagnostics of interstellar shocks

    International Nuclear Information System (INIS)

    Hartquist, T.W.; Oppenheimer, M.; Dalgarno, A.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km s -1 Substantial enhancements are predicted in the concentrations of the molecules H 2 S, SO, and SiO compared to those anticipated in cold interstellar clouds

  7. Molecular diagnostics of interstellar shocks

    Science.gov (United States)

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-02-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  8. How Culture Shock Affects Communication.

    Science.gov (United States)

    Barna, LaRay M.

    The paper defines the term "culture shock" and discusses the changes that this state can make in a person's behavior. Culture shock refers to the emotional and physiological reaction of high activation that is brought about by sudden immersion in a new culture. Because one's own culture shields one from the unknown and reduces the need to make…

  9. Molecular diagnostics of interstellar shocks

    Science.gov (United States)

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  10. Shock wave treatment in medicine

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 30; Issue 2 ... In the present paper we discuss the basic theory and application of shock waves and its history in medicine. The idea behind using shock wave therapy for orthopedic diseases is the stimulation of healing in tendons, surrounding tissue and bones. This is a ...

  11. Shock wave treatment in medicine

    Indian Academy of Sciences (India)

    Unknown

    to open surgery, the cost of the ESWT is very reasonable. But nevertheless it is necessary to improve the basic un ... In second group, shock waves are used to measure distances because of the low energy loss over large distances ... pared to a piezoelectric hydrophone. The rise time of an electrohydraulic generated shock ...

  12. Numerical modeling of slow shocks

    International Nuclear Information System (INIS)

    Winske, D.

    1987-01-01

    This paper reviews previous attempt and the present status of efforts to understand the structure of slow shocks by means of time dependent numerical calculations. Studies carried out using MHD or hybrid-kinetic codes have demonstrated qualitative agreement with theory. A number of unresolved issues related to hybrid simulations of the internal shock structure are discussed in some detail. 43 refs., 8 figs

  13. Dynamic shock wave: hammer blow

    International Nuclear Information System (INIS)

    Lackme, Claude

    1978-01-01

    The general properties of shocks, their generation and the conditions of reflexion to an interface are dealt with in turn. By then applying these concepts to a liquid column and its environment (wall, free area, closing devices) the hammer blow is presented as being a relatively weak shock [fr

  14. CP violating phenomena and theoretical results

    International Nuclear Information System (INIS)

    Grimus, W.

    1987-01-01

    An introduction to CP violating phenomena is given and the standard model and its most popular low energy extensions in this context are reviewed. The discussion comprises the minimal supersymmetric extension of the standard model, left-right symmetry, the standard model with more than one Higgs doublet and gauged horizontal symmetries. (Author)

  15. Collision and interaction phenomena - a historical outline

    International Nuclear Information System (INIS)

    Radmaneche, R.

    1977-09-01

    Collisions and interactions have become important for the description of matter. The author presents an outline which deals with elastic and inelastic collisions, with strong interactions, electromagnetic interactions, weak interactions and gravitational interactions. It is shown that the description of such processes has developed parallel with the understanding of matter and with the mechanism of the phenomena. Current and unsolved problems are mentioned

  16. Transport phenomena in materials processing---1990

    International Nuclear Information System (INIS)

    Bishop, B.J.; Lior, N.; Lavine, A.; Flik, M.; Karwe, M.V.; Bergman, T.L.; Beckermann, C.; Charmchi, M.

    1990-01-01

    The papers contained in this volume represent a wide range of current research interests in processes such as food and polymer processing, casting, welding, machining, laser cutting, and superconductor processing. This volume includes papers presented in four sessions: Heat Transfer in Materials Processing; Thermal Phenomena in Superconductor Processing; Heat Transfer in Food and Polymer Processing; Heat Transfer in CAsting and Welding

  17. Homoclinic phenomena in the gravitational collapse

    International Nuclear Information System (INIS)

    Koiller, J.; Mello Neto, J.R.T. de; Soares, I.D.

    1984-01-01

    A class of Bianchi IX cosmological models is shown to have chaotic gravitational collapse, due to Poincare's homoclinic phenomena. Such models can be programmed so that for any given positive integer N (N=infinity included) the universe undergoes N non-periodic oscillations (each oscillation requiring a long time) before collapsing. For N=infinity the universe undergoes periodic oscillations. (Author) [pt

  18. Novel experimentally observed phenomena in soft matter

    Indian Academy of Sciences (India)

    The resulting flow is non-Newtonian and is characterized by features such as shear rate-dependent viscosities and nonzero normal stresses. This article begins with an introduction to some unusual flow properties displayed by soft matter. Experiments that report a spectrum of novel phenomena exhibited by these materials, ...

  19. Some Phenomena on Negative Inversion Constructions

    Science.gov (United States)

    Sung, Tae-Soo

    2013-01-01

    We examine the characteristics of NDI (negative degree inversion) and its relation with other inversion phenomena such as SVI (subject-verb inversion) and SAI (subject-auxiliary inversion). The negative element in the NDI construction may be" not," a negative adverbial, or a negative verb. In this respect, NDI has similar licensing…

  20. Hyperchaotic phenomena in dynamic decision making

    DEFF Research Database (Denmark)

    Thomsen, Jesper Skovhus; Mosekilde, Erik; Sterman, John David

    1992-01-01

    of this article is to show how the decision making behavior of real people in simulated corporate environments can lead to chaotic, hyperchaotic and higher-order hyperchaotic phenomena. Characteristics features of these complicated forms of behavior are analyzed with particular emphasis on an interesting form...

  1. Reduplication phenomena: body, mind and archetype.

    Science.gov (United States)

    Garner, J

    2000-09-01

    The many biological and few psychodynamic explanations of reduplicative syndromes tend to have paralleled the dualism of the phenomenon with organic theories concentrating on form and dynamic theories emphasising content. This paper extends the contribution of psychoanalytic thinking to an elucidation of the form of the delusion. Literature on clinical and aetiological aspects of reduplicative phenomena is reviewed alongside a brief examination of psychoanalytic models not overtly related to these phenomena. The human experience of doubles as universal archetype is considered. There is an obvious aetiological role for brain lesions in delusional misidentifications, but psychological symptoms in an individual can rarely be reduced to an organic disorder. The splitting and doubling which occurs in the phenomena have resonances in cultural mythology and in theories from different schools of psychodynamic thought. For the individual patient and doctor, it is a diverting but potentially empty debate to endeavour to draw strict divisions between what is physical and what is psychological although both need to be investigated. Nevertheless, in patients in whom there is clear evidence of an organic contribution to aetiology a psychodynamic understanding may serve to illuminate the patient's experience. Organic brain disease or serious functional illness predispose to regression to earlier modes of archetypical and primitive thinking with concretization of the metaphorical and mythological world. Psychoanalytic models have a contribution in describing the form as well as the content of reduplicative phenomena.

  2. DOE natural phenomena hazards mitigation conference: proceedings

    International Nuclear Information System (INIS)

    1985-10-01

    The conference includes sessions which present an overview of DOE programs, available codes, standards and criteria, examples of designs and upgrades from the DOE complex, lessons learned from past natural phenomena, ground motion, seismic evaluation of equipment, and applications of probabilistic risk assessment techniques to DOE facilities. Separate abstracts have been prepared for individual papers

  3. Interface-induced phenomena in magnetism

    NARCIS (Netherlands)

    Hellman, Frances; Hoffmann, A.; Tserkovnyak, Yaroslav; Beach, Geoffrey S.D.; Fullerton, Eric E.; Leighton, Chris; Macdonald, Allan H.; Ralph, Daniel C.; Arena, Dario A.; Dürr, Hermann A.; Fischer, Peter; Grollier, Julie; Heremans, Joseph P.; Jungwirth, Tomas; Kimel, Alexey V.; Koopmans, B.; Krivorotov, Ilya N.; May, Steven J.; Petford-Long, Amanda K.; Rondinelli, James M.; Samarth, Nitin; Schuller, Ivan K.; Slavin, Andrei N.; Stiles, Mark D.; Tchernyshyov, Oleg; Thiaville, André; Zink, Barry L.

    2017-01-01

    This article reviews static and dynamic interfacial effects in magnetism, focusing on interfacially driven magnetic effects and phenomena associated with spin-orbit coupling and intrinsic symmetry breaking at interfaces. It provides a historical background and literature survey, but focuses on

  4. Analysis of induction phenomena in thermonuclear experiments

    International Nuclear Information System (INIS)

    Deeds, W.E.; Dodd, C.V.

    1976-01-01

    Many of the problems involving transients induced by changing currents in the large coils of thermonuclear machines are identical to those arising in nondestructive testing by eddy currents. There are three chief methods used for calculating such induction phenomena: analytical boundary-value solutions, relaxation or iteration techniques, and model experiments. Some of the results obtained by each of these methods are described below

  5. Modelling of flow phenomena during DC casting

    NARCIS (Netherlands)

    Zuidema, J.

    2005-01-01

    Modelling of Flow Phenomena during DC Casting Jan Zuidema The production of aluminium ingots, by semi-continuous casting, is a complex process. DC Casting stands for direct chill casting. During this process liquid aluminium transforms to solid aluminium while cooling down. This is not an

  6. Electrical breakdown phenomena of dielectric elastomers

    DEFF Research Database (Denmark)

    Yu, Liyun; Mateiu, Ramona Valentina; Skov, Anne Ladegaard

    2017-01-01

    years. However, optimization with respect to the dielectric permittivity solely may lead to other problematic phenomena such as premature electrical breakdown. In this work, we focus on the chloro propyl functionalized silicone elastomers prepared in Madsen et al[2] and we investigate the electrical...

  7. Simple classical approach to spin resonance phenomena

    DEFF Research Database (Denmark)

    Gordon, R A

    1977-01-01

    A simple classical method of describing spin resonance in terms of the average power absorbed by a spin system is discussed. The method has several advantages over more conventional treatments, and a number of important spin resonance phenomena, not normally considered at the introductory level...

  8. Transport phenomena in strongly correlated Fermi liquids

    International Nuclear Information System (INIS)

    Kontani, Hiroshi

    2013-01-01

    Comprehensive overview. Written by an expert of this topic. Provides the reader with current developments in the field. In conventional metals, various transport coefficients are scaled according to the quasiparticle relaxation time, τ, which implies that the relaxation time approximation (RTA) holds well. However, such a simple scaling does not hold in many strongly correlated electron systems, reflecting their unique electronic states. The most famous example would be cuprate high-Tc superconductors (HTSCs), where almost all the transport coefficients exhibit a significant deviation from the RTA results. To better understand the origin of this discrepancy, we develop a method for calculating various transport coefficients beyond the RTA by employing field theoretical techniques. Near the magnetic quantum critical point, the current vertex correction (CVC), which describes the electron-electron scattering beyond the relaxation time approximation, gives rise to various anomalous transport phenomena. We explain anomalous transport phenomena in cuprate HTSCs and other metals near their magnetic or orbital quantum critical point using a uniform approach. We also discuss spin related transport phenomena in strongly correlated systems. In many d- and f-electron systems, the spin current induced by the spin Hall effect is considerably greater because of the orbital degrees of freedom. This fact attracts much attention due to its potential application in spintronics. We discuss various novel charge, spin and heat transport phenomena in strongly correlated metals.

  9. Solar Phenomena Associated with "EIT Waves"

    Science.gov (United States)

    Biesecker, D. A.; Myers, D. C.; Thompson, B. J.; Hammer, D. M.; Vourlidas, A.

    2002-01-01

    In an effort to understand what an 'EIT wave' is and what its causes are, we have looked for correlations between the initiation of EIT waves and the occurrence of other solar phenomena. An EIT wave is a coronal disturbance, typically appearing as a diffuse brightening propagating across the Sun. A catalog of EIT waves, covering the period from 1997 March through 1998 June, was used in this study. For each EIT wave, the catalog gives the heliographic location and a rating for each wave, where the rating is determined by the reliability of the observations. Since EIT waves are transient, coronal phenomena, we have looked for correlations with other transient, coronal phenomena: X-ray flares, coronal mass ejections (CMEs), and metric type II radio bursts. An unambiguous correlation between EIT waves and CMEs has been found. The correlation of EIT waves with flares is significantly weaker, and EIT waves frequently are not accompanied by radio bursts. To search for trends in the data, proxies for each of these transient phenomena are examined. We also use the accumulated data to show the robustness of the catalog and to reveal biases that must be accounted for in this study.

  10. Rogue and shock waves in nonlinear dispersive media

    CERN Document Server

    Resitori, Stefania; Baronio, Fabio

    2016-01-01

    This self-contained set of lectures addresses a gap in the literature by providing a systematic link between the theoretical foundations of the subject matter and cutting-edge applications in both geophysical fluid dynamics and nonlinear optics. Rogue and shock waves are phenomena that may occur in the propagation of waves in any nonlinear dispersive medium. Accordingly, they have been observed in disparate settings – as ocean waves, in nonlinear optics, in Bose-Einstein condensates, and in plasmas. Rogue and dispersive shock waves are both characterized by the development of extremes: for the former, the wave amplitude becomes unusually large, while for the latter, gradients reach extreme values. Both aspects strongly influence the statistical properties of the wave propagation and are thus considered together here in terms of their underlying theoretical treatment. This book offers a self-contained graduate-level text intended as both an introduction and reference guide for a new generation of scientists ...

  11. Slow shocks and their transition to fast shocks in the inner solar wind

    International Nuclear Information System (INIS)

    Wang, Y.C.

    1987-01-01

    The jump conditions of MHD shocks may be directly calculated as functions of three upstream conditions: the shock Alfven number based on the normal component of the relative shock speed, the shock angle, and the plasma β value. The shock Alfven number is less than 1 for a slow shock and greater than 1 for a fast shock. A traveling, forward shock can be a slow shock in coronal space, where the Alfven speed is of the order of 1000 km/s. The surface of a forward slow shock has a bow-shaped geometry with its nose facing toward the sun. The decrease in the Alfven speed at increasing heliocentric distance causes the shock Alfven number of a forward slow shock to become greater than 1, and the shock eventually evolves from a slow shock into a fast shock. During the transition the shock system consists of a slow shock, a fast shock, and a rotational discontinuity. They intersect along a closed transition line. As the system moves outward from the sun, the area enclosed by the transition line expands, the fast shock grows stronger, and the slow shock becomes weaker. Eventually, the slow shock diminishes, and the entire shock system evolves into a forward fast shock. copyrightAmerican Geophysical Union 1987

  12. A soap film shock tube to study two-dimensional compressible flows

    Energy Technology Data Exchange (ETDEWEB)

    Wen, C.Y.; Chen, Y.M.; Chang-Jian, S.K. [Dept. of Mechanical Engineering, Da-Yeh University Chang-Hwa (Taiwan)

    2001-07-01

    A new experimental approach to the study of the two-dimensional compressible flow phenomena is presented. In this technique, a variety of compressible flows were generated by bursting plane vertical soap films. An aureole and a ''shock wave'' preceding the rim of the expanding hole were clearly observed using traditional high-speed flash photography and a fast line-scan charge coupled device (CCD) camera. The moving shock wave images obtained from the line-scan CCD camera were similar to the x-t diagrams in gas dynamics. The moving shock waves cause thickness jumps and induce supersonic flows. Photographs of the supersonic flows over a cylinder and a wedge are presented. The results suggest clearly the feasibility of the ''soap film shock tube''. (orig.)

  13. Geomorphology: the Shock of the Familiar

    Science.gov (United States)

    Dietrich, W. E.

    2008-12-01

    Everyone experiences landscapes and has a sense about how they work: water runs down hill, it erodes and carries sediments, and that's about it, right? Introductory earth science text books are uniformly qualitative about the field, and leave one with little sense of wonder, and certainly not "shock". But four shocks occur if one peels away the first impressions. First, landscapes are surprisingly similar: the same forms are repeated in virtually all environments, including under the ocean and on other planets. Second, we lack theory and mechanistic observations to answer many simple first-order questions, e.g. what controls the width of a river, how does rock type control hillslope form and erosion rate, or, is there a topographic signature of life. Third, there are unexpected connections between surface erosion, deep earth processes, and climate. And fourth, the field itself, despite having been a subject of study for well over 100 years, is currently experiencing a revolution of ideas and discoveries through new tools, observatories, centers, journals, books, contributions of researchers from other disciplines, and from a significant hiring of young researchers in geomorphology. Deep messages await discovery in the simple landforms surrounding us.

  14. Shock Interaction with Random Spherical Particle Beds

    Science.gov (United States)

    Neal, Chris; Mehta, Yash; Salari, Kambiz; Jackson, Thomas L.; Balachandar, S. "Bala"; Thakur, Siddharth

    2016-11-01

    In this talk we present results on fully resolved simulations of shock interaction with randomly distributed bed of particles. Multiple simulations were carried out by varying the number of particles to isolate the effect of volume fraction. Major focus of these simulations was to understand 1) the effect of the shockwave and volume fraction on the forces experienced by the particles, 2) the effect of particles on the shock wave, and 3) fluid mediated particle-particle interactions. Peak drag force for particles at different volume fractions show a downward trend as the depth of the bed increased. This can be attributed to dissipation of energy as the shockwave travels through the bed of particles. One of the fascinating observations from these simulations was the fluctuations in different quantities due to presence of multiple particles and their random distribution. These are large simulations with hundreds of particles resulting in large amount of data. We present statistical analysis of the data and make relevant observations. Average pressure in the computational domain is computed to characterize the strengths of the reflected and transmitted waves. We also present flow field contour plots to support our observations. U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science Academic Alliance Program, under Contract No. DE-NA0002378.

  15. Astrophysical phenomena related to supermassive black holes

    Science.gov (United States)

    Pott, Jörg-Uwe

    2006-12-01

    The thesis contains the results of my recent projects in astrophysical research. All projects aim at pushing the limits of our knowledge about the interaction between a galaxy, the fundamental building block of today's universe, and a supermassive black hole (SMBH) at its center. Over the past years a lot of observational evidence has been gathered for the current understanding, that at least a major part of the galaxies with a stellar bulge contain central SMBHs. The typical extragalactic approach consists of searching for the spectroscopic pattern of Keplerian rotation, produced by stars and gas, when orbiting a central dark mass (Kormendy & Richstone 1995). It suggests that a significant fraction of large galaxies host in their very nucleus a SMBH of millions to billions of solar masses (Kormendy & Gebhardt 2001). In the closest case, the center of our Milky Way, the most central stars, which can be imaged, were shown to move on orbits with circulation times of a few decades only, evidencing a mass and compactness of the dark counter part of the Keplerian motion, which can only be explained by a SMBH (Eckart & Genzel 1996; Ghez et al. 2000; Schödel et al. 2002). Having acknowledged the widespread existence of SMBHs the obvious next step is investigating the interaction with their environment. Although the basic property of a SMBH, which is concentrating a huge amount of mass in a ludicrously small volume defined by the Schwarzschild radius, only creates a deep gravitational trough, its existence evokes much more phenomena than simply attracting the surrounding matter. It can trigger or exacerbate star formation via tidal forces (Morris 1993). It shapes the distribution of its surrounding matter to accretion discs, which themselves release gravitational potential energy as radiation, possibly due to magnetic friction (Blandford 1995). The radiation efficiency of such active galactic nuclei (AGN) can become roughly 100 times more efficient than atomic nuclear

  16. Shocking matter to extreme conditions

    International Nuclear Information System (INIS)

    Gupta, Y.M.; Sharma, S.M.

    1997-01-01

    A good understanding of the thermodynamic response of matter at high compression and high energy densities is important to several areas of physics. Shock-wave experiments are uniquely suited for obtaining data at extreme conditions, and a shock-compressed matter can be viewed as a condensed system with or without dissociation or as a strongly coupled plasma. This article reviews work by Da Silva et al. in which irradiances ranging from 5x10 superscript 12 to 2x10 superscript 14 W/cm 2 were used to generate 8- to 10-ns square pulses in liquid deuterium. The authors demonstrated negligible pre-heating of the sample, steady propagation of the shock wave, and direct determination of the shock wave velocity along with particle velocity and density in the shocked state. Da Silva et al. results are compared with models and other experimental information, and the usefulness of the data in other areas is assessed. 11 refs., 1 fig

  17. Electron transport and shock ignition

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A R; Tzoufras, M, E-mail: t.bell1@physics.ox.ac.uk [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

    2011-04-15

    Inertial fusion energy (IFE) offers one possible route to commercial energy generation. In the proposed 'shock ignition' route to fusion, the target is compressed at a relatively low temperature and then ignited using high intensity laser irradiation which drives a strong converging shock into the centre of the fuel. With a series of idealized calculations we analyse the electron transport of energy into the target, which produces the pressure responsible for driving the shock. We show that transport in shock ignition lies near the boundary between ablative and heat front regimes. Moreover, simulations indicate that non-local effects are significant in the heat front regime and might lead to increased efficiency by driving the shock more effectively and reducing heat losses to the plasma corona.

  18. Oscillating nonlinear acoustic shock waves

    DEFF Research Database (Denmark)

    Gaididei, Yuri; Rasmussen, Anders Rønne; Christiansen, Peter Leth

    2016-01-01

    We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show that at resona......We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show...... polynomial in the space and time variables, we find analytical approximations to the observed single shock waves in an infinitely long tube. Using perturbation theory for the driven acoustic system approximative analytical solutions for the off resonant case are determined....

  19. Traveling foreshocks and transient foreshock phenomena

    OpenAIRE

    Kajdič, P.; Blanco-Cano, X.; Omidi, N.; Rojas-Castillo, D.; Sibeck, D.G.; Billingham, L.

    2017-01-01

    We use the multispacecraft capabilities of the Cluster and Time History of Events and Macroscale Interactions during Substorms (THEMIS) missions to show that two types of foreshock may be detected in spacecraft data. One is the global foreshock that appears upstream of the Earth's quasi-parallel bow shock under steady or variable interplanetary magnetic field. Another type is a traveling foreshock that is bounded by two rotational discontinuities in the interplanetary magnetic field and propa...

  20. Shock waves & explosions

    CERN Document Server

    Sachdev, PL

    2004-01-01

    Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods to a wide audience in a clear and thorough way. Beginning with an overview of the research on combustion and gas dynamics in the 1970s and 1980s, the author brings you up to date by covering modeling techniques and asymptotic and perturbative methods and ending with a chapter on computational methods.Most of the book deals with the mathematical analysis of explosions, but computational results are also included wherever they are available. Historical perspectives are provided on the advent of nonlinear science, as well as on the mathematical study of the blast wave phenomenon, both when visualized as a point explosion and when simulated as the expansion of a high-pressure ...

  1. Analysis of shock implosion

    Energy Technology Data Exchange (ETDEWEB)

    Mishkin, E.A.; Alejaldre, C. (Polytechnic Inst. of New York, Brooklyn (USA))

    1984-06-01

    An imploding shock wave, coming from infinity, moves through an ideal gas with the adiabatic constant ..gamma... To define a single-valued self-similar coefficient over the whole classical interval 1<..gamma..

  2. Experiencing the enchantment of place and mobility

    DEFF Research Database (Denmark)

    Bærenholdt, Jørgen Ole

    2016-01-01

    in several layers of reality. To better understand experiences taking place in intersections between realities, J.R.R. Tolkien’s concept of how real enchantment produces a Secondary World suggests that we see fantasy as real, and this proposition is compared to Georg Simmel’s more modernist suggestion......Experiences of place and mobility play central roles not only in what was traditionally understood as tourism, but also in the broader practices of travelling and visiting sites and sights. On the one hand, such experiences are performed to an extent where it is difficult to isolate the sites...... and movements experienced per se, since visitors and travellers take part in ‘doing’ places and mobility. On the other, experience sites and routes stand out with specific traces and characteristics affording some – and not other – experiences. This paper discusses conceptual understandings that may help...

  3. Cognitive dissonance experienced by nurse practitioner faculty.

    Science.gov (United States)

    Fontenot, Holly B; Hawkins, Joellen W; Weiss, Josie A

    2012-08-01

    The purpose of this study was to explicate the concept of cognitive dissonance as experienced and reported by nurse practitioner (NP) faculty members. Responses from NP faculty members to an online survey about their experiences with cognitive dissonance. The respondents detailed their experiences with cognitive dissonance, citing differences between expectations for which they are rewarded and those for which they are paid. Expecting all faculty members to excel in practice, research, teaching, and service may create unrealistic workloads for NP faculty members. Examining expectations and considering creation of a clinical track for faculty who practice may be options administrators of NP programs might explore. ©2012 The Author(s) Journal compilation ©2012 American Academy of Nurse Practitioners.

  4. Challenges experienced by debt counsellors in Gauteng

    Directory of Open Access Journals (Sweden)

    Kgomotso Masilo

    2015-09-01

    Full Text Available Gauteng, Province of South Africa is experiencing a decreasing number of registered and practising debt counsellors. This paper investigates and assesses the challenges that debt counsellors in Gauteng experiences. Fifteen debt counsellors from three municipalities of Gauteng were interviewed. Data was analysed using ATLAS ti. The paper concluded that though debt counsellors are complying with the regulations in rendering debt counselling service, they still had challenges regarding backlogs in debt review. The paper recommends that debt counsellors should be adequately trained and should restructure their rehabilitation methods on the one hand and the National Credit Regulator should monitor debt counsellors’ practices and assist them with their queries on the other hand.

  5. Time-resolved diffraction of shock-released SiO2 and diaplectic glass formation

    International Nuclear Information System (INIS)

    Gleason, A. E.; Bolme, C. A.; Lee, H. J.; Nagler, B.

    2017-01-01

    Understanding how rock-forming minerals transform under shock loading is critical for modeling collisions between planetary bodies, interpreting the significance of shock features in minerals and for using them as diagnostic indicators of impact conditions, such as shock pressure. To date, our understanding of the formation processes experienced by shocked materials is based exclusively on ex situ analyses of recovered samples. Formation mechanisms and origins of commonly observed mesoscale material features, such as diaplectic (i.e., shocked) glass, remain therefore controversial and unresolvable. Here in this paper we show in situ pump-probe X-ray diffraction measurements on fused silica crystallizing to stishovite on shock compression and then converting to an amorphous phase on shock release in only 2.4 ns from 33.6 GPa. Recovered glass fragments suggest permanent densification. These observations of real-time diaplectic glass formation attest that it is a back-transformation product of stishovite with implications for revising traditional shock metamorphism stages.

  6. The cosmic-ray shock structure problem for relativistic shocks

    Science.gov (United States)

    Webb, G. M.

    1985-01-01

    The time asymptotic behaviour of a relativistic (parallel) shock wave significantly modified by the diffusive acceleration of cosmic-rays is investigated by means of relativistic hydrodynamical equations for both the cosmic-rays and thermal gas. The form of the shock structure equation and the dispersion relation for both long and short wavelength waves in the system are obtained. The dependence of the shock acceleration efficiency on the upstream fluid spped, long wavelength Mach number and the ratio N = P sub co/cP sub co+P sub go)(Psub co and P sub go are the upstream cosmic-ray and thermal gas pressures respectively) are studied.

  7. Cosmic-ray shock acceleration in oblique MHD shocks

    Science.gov (United States)

    Webb, G. M.; Drury, L. OC.; Volk, H. J.

    1986-01-01

    A one-dimensional, steady-state hydrodynamical model of cosmic-ray acceleration at oblique MHD shocks is presented. Upstream of the shock the incoming thermal plasma is subject to the adverse pressure gradient of the accelerated particles, the J x B force, as well as the thermal gas pressure gradient. The efficiency of the acceleration of cosmic-rays at the shock as a function of the upstream magnetic field obliquity and upstream plasma beta is investigated. Astrophysical applications of the results are briefly discussed.

  8. Disequilibrium analysis of three macroeconomies after two OPEC shocks: US, Germany, and Japan

    Energy Technology Data Exchange (ETDEWEB)

    Lin, G.Y.

    1983-01-01

    Economic performance in each economy is discussed and an appraisal of policy choices is given. Two OPEC shocks, (1973-1974) and (1979-1980), are specially brought out because of their uniqueness in economic history and also their dominant feature as supply-side shocks which are ignored in the conventional Keynesian economics. The model considers both aggregate demand and aggregate supply in an economy, and provides a framework to describe economic phenomena after OPEC shocks. The model consists of two dynamic adjustments, quantity adjustments and price adjustments. It is assumed that quantity adjustments are observed more frequently than price adjustments in the short run. However, prices are not perfectly rigid but less frequently adjusted. Under this framework, the phenomenon of classical unemployment can be distinguished from Keynesian unemployment for the purpose of discussion. The results showed that all these three economies were in the classical unemployment regime during the first oil shock and, during the second oil shock, Germany and Japan were in the classical unemployment regime while US was in the Keynesian unemployment regime. However, both Germany and Japan performed comparatively better than the US during the second oil shock in terms of real growth of GNP and inflation rates. It demonstrated that Germany and Japan were aware of the feature of supply shocks and paid attention to both demand and supply, especially to promote supply by reducing the dependence on oil and by increasing the flexibility of money wage rates.

  9. Chondrule destruction in nebular shocks

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, Emmanuel; Thompson, Christopher, E-mail: ejacquet@mnhn.fr [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St George Street, Toronto, ON M5S 3H8 (Canada)

    2014-12-10

    Chondrules are millimeter-sized silicate spherules ubiquitous in primitive meteorites, but whose origin remains mysterious. One of the main proposed mechanisms for producing them is melting of solids in shock waves in the gaseous protoplanetary disk. However, evidence is mounting that chondrule-forming regions were enriched in solids well above solar abundances. Given the high velocities involved in shock models, destructive collisions would be expected between differently sized grains after passage of the shock front as a result of differential drag. We investigate the probability and outcome of collisions of particles behind a one-dimensional shock using analytic methods as well as a full integration of the coupled mass, momentum, energy, and radiation equations. Destruction of protochondrules seems unavoidable for solid/gas ratios ε ≳ 0.1, and possibly even for solar abundances because of 'sandblasting' by finer dust. A flow with ε ≳ 10 requires much smaller shock velocities (∼2 versus 8 km s{sup –1}) in order to achieve chondrule-melting temperatures, and radiation trapping allows slow cooling of the shocked fragments. Initial destruction would still be extensive; although re-assembly of millimeter-sized particles would naturally occur by grain sticking afterward, the compositional heterogeneity of chondrules may be difficult to reproduce. We finally note that solids passing through small-scale bow shocks around few kilometer-sized planetesimals might experience partial melting and yet escape fragmentation.

  10. Exotic Phenomena Searches at Hadron Colliders

    CERN Document Server

    INSPIRE-00305407

    2013-01-01

    This review presents a selection of the final results of searches for various exotic physics phenomena in proton-proton collisions at $\\sqrt{s}=7$ and 8~TeV delivered by the LHC and collected with the ATLAS and CMS detectors in 2011 (5 $fb^{-1}$) and in the first part of 2012 (4 $fb^{-1}$). Searches for large extra dimensions, gravitons, microscopic black holes, long-lived particles, dark matter, and leptoquarks are presented in this report. No sign of new physics beyond the standard model has been observed so far. In the majority of the cases these searches set the most stringent limits to date on the aforementioned new physics phenomena.

  11. Renormalization group theory of critical phenomena

    International Nuclear Information System (INIS)

    Menon, S.V.G.

    1995-01-01

    Renormalization group theory is a framework for describing those phenomena that involve a multitude of scales of variations of microscopic quantities. Systems in the vicinity of continuous phase transitions have spatial correlations at all length scales. The renormalization group theory and the pertinent background material are introduced and applied to some important problems in this monograph. The monograph begins with a historical survey of thermal phase transitions. The background material leading to the renormalization group theory is covered in the first three chapters. Then, the basic techniques of the theory are introduced and applied to magnetic critical phenomena in the next four chapters. The momentum space approach as well as the real space techniques are, thus, discussed in detail. Finally, brief outlines of applications of the theory to some of the related areas are presented in the last chapter. (author)

  12. Transport phenomena in strongly correlated Fermi liquids

    CERN Document Server

    Kontani, Hiroshi

    2013-01-01

    In conventional metals, various transport coefficients are scaled according to the quasiparticle relaxation time, \\tau, which implies that the relaxation time approximation (RTA) holds well. However, such a simple scaling does not hold in many strongly correlated electron systems, reflecting their unique electronic states. The most famous example would be cuprate high-Tc superconductors (HTSCs), where almost all the transport coefficients exhibit a significant deviation from the RTA results. To better understand the origin of this discrepancy, we develop a method for calculating various transport coefficients beyond the RTA by employing field theoretical techniques. Near the magnetic quantum critical point, the current vertex correction (CVC), which describes the electron-electron scattering beyond the relaxation time approximation, gives rise to various anomalous transport phenomena. We explain anomalous transport phenomena in cuprate HTSCs and other metals near their magnetic or orbital quantum critical poi...

  13. Coherence Phenomena in Coupled Optical Resonators

    Science.gov (United States)

    Smith, D. D.; Chang, H.

    2004-01-01

    We predict a variety of photonic coherence phenomena in passive and active coupled ring resonators. Specifically, the effective dispersive and absorptive steady-state response of coupled resonators is derived, and used to determine the conditions for coupled-resonator-induced transparency and absorption, lasing without gain, and cooperative cavity emission. These effects rely on coherent photon trapping, in direct analogy with coherent population trapping phenomena in atomic systems. We also demonstrate that the coupled-mode equations are formally identical to the two-level atom Schrodinger equation in the rotating-wave approximation, and use this result for the analysis of coupled-resonator photon dynamics. Notably, because these effects are predicted directly from coupled-mode theory, they are not unique to atoms, but rather are fundamental to systems of coherently coupled resonators.

  14. Tunable caustic phenomena in electron wavefields

    Energy Technology Data Exchange (ETDEWEB)

    Tavabi, Amir Hossein, E-mail: a.tavabi@fz-juelich.de [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Migunov, Vadim; Dwyer, Christian; Dunin-Borkowski, Rafal E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Pozzi, Giulio [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Department of Physics and Astronomy, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy)

    2015-10-15

    Novel caustic phenomena, which contain fold, butterfly and elliptic umbilic catastrophes, are observed in defocused images of two approximately collinear oppositely biased metallic tips in a transmission electron microscope. The observed patterns depend sensitively on defocus, on the applied voltage between the tips and on their separation and lateral offset. Their main features are interpreted on the basis of a projected electrostatic potential model for the electron-optical phase shift. - Highlights: • Electron-optical caustics are observed in defocused images of biased metallic tips. • The caustics depend on defocus, on the bias between the tips and on their separation. • The setup offers the flexibility to study a wide variety of caustic phenomena.

  15. Basic transport phenomena in materials engineering

    CERN Document Server

    Iguchi, Manabu

    2014-01-01

    This book presents the basic theory and experimental techniques of transport phenomena in materials processing operations. Such fundamental knowledge is highly useful for researchers and engineers in the field to improve the efficiency of conventional processes or develop novel technology. Divided into four parts, the book comprises 11 chapters describing the principles of momentum transfer, heat transfer, and mass transfer in single phase and multiphase systems. Each chapter includes examples with solutions and exercises to facilitate students’ learning. Diagnostic problems are also provided at the end of each part to assess students’ comprehension of the material.  The book is aimed primarily at students in materials science and engineering. However, it can also serve as a useful reference text in chemical engineering as well as an introductory transport phenomena text in mechanical engineering. In addition, researchers and engineers engaged in materials processing operations will find the material use...

  16. Coherent topological phenomena in protein folding

    DEFF Research Database (Denmark)

    Bohr, Henrik; Brunak, Søren; Bohr, Jakob

    1997-01-01

    A theory is presented for coherent topological phenomena in protein dynamics with implications for protein folding and stability. We discuss the relationship to the writhing number used in knot diagrams of DNA. The winding state defines a long-range order along the backbone of a protein with long......-range excitations, `wring' modes, that play an important role in protein denaturation and stability. Energy can be pumped into these excitations, either thermally or by an external force....

  17. Workshop on Nonlinear Phenomena in Complex Systems

    CERN Document Server

    1989-01-01

    This book contains a thorough treatment of neural networks, cellular-automata and synergetics, in an attempt to provide three different approaches to nonlinear phenomena in complex systems. These topics are of major interest to physicists active in the fields of statistical mechanics and dynamical systems. They have been developed with a high degree of sophistication and include the refinements necessary to work with the complexity of real systems as well as the more recent research developments in these areas.

  18. Role of spinning electrons in paramagnetic phenomena

    International Nuclear Information System (INIS)

    Bose, D.M.

    1986-06-01

    An attempt is made to explain paramagnetic phenomena without assuming the orientation of a molecule or ion in a magnetic field. Only the spin angular momentum is assumed to be responsible. A derivative of the Gurie-Langevin law and the magnetic moments of ions are given as a function of the number of electrons in an inner, incomplete shell. An explanation of Gerlach's experiments with iron and nickel vapors is attempted. An explanation of magnetomechanical experiments with ferromagnetic elements is given

  19. From critical phenomena to gauge gields

    International Nuclear Information System (INIS)

    Le Bellac, M.

    1988-01-01

    In this book the author gives an introduction to the following questions: critical phenomena (Landau theory, renormalization group, two dimensional models); Perturbation theory and renormalization, scalar euclidian field (Feynman diagrams, Callan-Symanzik equations); Quantum theory of scalar fields (path integrals in quantum mechanics and statistical mechanics, green functions and S matrix, quantization of Klein-Gordon field); Gauge theories (quantization of Dirac field and electromagnetic field, quantum electrodynamics, non-abelian gauge theories) [fr

  20. Pseudogap phenomena in ultracold atomic Fermi gases

    OpenAIRE

    Chen, Qijin; Wang, Jibiao

    2014-01-01

    The pairing and superfluid phenomena in a two-component ultracold atomic Fermi gas is an analogue of Cooper pairing and superconductivity in an electron system, in particular, the high $T_c$ superconductors. Owing to the various tunable parameters that have been made accessible experimentally in recent years, atomic Fermi gases can be explored as a prototype or quantum simulator of superconductors. It is hoped that, utilizing such an analogy, the study of atomic Fermi gases may shed light to ...

  1. Occult Phenomena in Sherlock Holmes the Movie

    OpenAIRE

    NAMAZCARRA, CHRIESHER

    2014-01-01

    Keywords: Occult phenomena, Sherlock Holmes, movie. Lately, it is not difficult for people to find occult practices. There are many television programs and movie which air mystical programme aggressively to raise the rating and attract the viewers. A movie that raise occultism theme is Sherlock Holmes, the Movie. This movie tells about the struggle of detective Sherlock Holmes to fight the black magic power of Lord Blackwood.To carry out the study, the theories of Occultism such as the secrec...

  2. Conformal field theories and critical phenomena

    International Nuclear Information System (INIS)

    Xu, Bowei

    1993-01-01

    In this article we present a brief review of the conformal symmetry and the two dimensional conformal quantum field theories. As concrete applications of the conformal theories to the critical phenomena in statistical systems, we calculate the value of central charge and the anomalous scale dimensions of the Z 2 symmetric quantum chain with boundary condition. The results are compatible with the prediction of the conformal field theories

  3. Simulation of mechanical shock environments

    International Nuclear Information System (INIS)

    Lalanne, Christian.

    1975-07-01

    Shocks can produce a severe mechanical environment which must be taken into account when designing and developing new equipments. After some mathematical (Laplace and Fourier transforms) and mechanical recalls (response of a one degree freedom system to a sinusoidal excitation), different analysis methods are compared, these methods being the most used now to compare relative severities of tests and establish specifications. A few chapter deal with the different properties of simple, easy to produce, shock shapes. Then some now-in-use programmators or shock-machines specifications are shown. A final chapter concerns acceleration transducers [fr

  4. Particle acceleration in modified shocks

    International Nuclear Information System (INIS)

    Drury, L.O'C.; Axford, W.I.; Summers, D.

    1982-01-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed. (author)

  5. Particle acceleration in modified shocks

    Energy Technology Data Exchange (ETDEWEB)

    Drury, L.O' C. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.)); Axford, W.I. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany, F.R.)); Summers, D. (Memorial Univ. of Newfoundland, St. John' s (Canada))

    1982-03-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed.

  6. Shocks in the Early Universe.

    Science.gov (United States)

    Pen, Ue-Li; Turok, Neil

    2016-09-23

    We point out a surprising consequence of the usually assumed initial conditions for cosmological perturbations. Namely, a spectrum of Gaussian, linear, adiabatic, scalar, growing mode perturbations not only creates acoustic oscillations of the kind observed on very large scales today, it also leads to the production of shocks in the radiation fluid of the very early Universe. Shocks cause departures from local thermal equilibrium as well as create vorticity and gravitational waves. For a scale-invariant spectrum and standard model physics, shocks form for temperatures 1  GeVUniverse as early as 10^{-30}  sec after the big bang.

  7. An interpretation of passive containment cooling phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Bum-Jin [Ministry of Science & Technology, Kyunggi-Do (Korea, Democratic People`s Republic of); Kang, Chang-Sun, [Seoul National Univ. (Korea, Democratic People`s Republic of)

    1995-09-01

    A simplified interpretation model for the cooling capability of the Westinghouse type PCCS is proposed in this paper. The PCCS domain was phenomenologically divided into 3 regions; water entrance effect region, asymptotic region, and air entrance effect region. The phenomena in the asymptotic region is focused in this paper. Due to the very large height to thickness ratio of the water film, the length of the asymptotic region is estimated to be over 90% of the whole domain. Using the analogy between heat and mass transfer phenomena in a turbulent situation, a new dependent variable combining temperature and vapor mass fraction was defined. The similarity between the PCCS phenomena, which contains the sensible and latent heat transfer, and the buoyant air flow on a vertical heated plate is derived. The modified buoyant coefficient and thermal conductivity were defined. Using these newly defined variable and coefficients, the modified correlation for the interfacial heat fluxes and the ratios of latent heat transfer to sensible heat transfer is established. To verify the accuracy of the correlation, the results of this study were compared with the results of other numerical analyses performed for the same configuration and they are well within the range of 15% difference.

  8. Quantum Chess: Making Quantum Phenomena Accessible

    Science.gov (United States)

    Cantwell, Christopher

    Quantum phenomena have remained largely inaccessible to the general public. There tends to be a scare factor associated with the word ``Quantum''. This is in large part due to the alien nature of phenomena such as superposition and entanglement. However, Quantum Computing is a very active area of research and one day we will have games that run on those quantum computers. Quantum phenomena such as superposition and entanglement will seem as normal as gravity. Is it possible to create such games today? Can we make games that are built on top of a realistic quantum simulation and introduce players of any background to quantum concepts in a fun and mentally stimulating way? One of the difficulties with any quantum simulation run on a classical computer is that the Hilbert space grows exponentially, making simulations of an appreciable size physically impossible due largely to memory restrictions. Here we will discuss the conception and development of Quantum Chess, and how to overcome some of the difficulties faced. We can then ask the question, ``What's next?'' What are some of the difficulties Quantum Chess still faces, and what is the future of quantum games?

  9. Thermal transport phenomena in nanoparticle suspensions

    International Nuclear Information System (INIS)

    Cardellini, Annalisa; Fasano, Matteo; Bozorg Bigdeli, Masoud; Chiavazzo, Eliodoro; Asinari, Pietro

    2016-01-01

    Nanoparticle suspensions in liquids have received great attention, as they may offer an approach to enhance thermophysical properties of base fluids. A good variety of applications in engineering and biomedicine has been investigated with the aim of exploiting the above potential. However, the multiscale nature of nanosuspensions raises several issues in defining a comprehensive modelling framework, incorporating relevant molecular details and much larger scale phenomena, such as particle aggregation and their dynamics. The objectives of the present topical review is to report and discuss the main heat and mass transport phenomena ruling macroscopic behaviour of nanosuspensions, arising from molecular details. Relevant experimental results are included and properly put in the context of recent observations and theoretical studies, which solved long-standing debates about thermophysical properties enhancement. Major transport phenomena are discussed and in-depth analysis is carried out for highlighting the role of geometrical (nanoparticle shape, size, aggregation, concentration), chemical (pH, surfactants, functionalization) and physical parameters (temperature, density). We finally overview several computational techniques available at different scales with the aim of drawing the attention on the need for truly multiscale predictive models. This may help the development of next-generation nanoparticle suspensions and their rational use in thermal applications. (topical review)

  10. Physical phenomena as sense determinate occurrences

    International Nuclear Information System (INIS)

    Sommer, H.J.

    2005-01-01

    In the view of El Naschie's E Infinity theory [Chaos, Solitons and Fractals 22 (2004) 495], our physical laws emerge from a chaotic underground, a 'Dirac-sea'. But we have no direct access from our observations to this chaotic world and this implies that the meaning of the correspondence between the phenomena we obtain by our cognition and their causal structures remains hidden to us. The fundamental process which produces our cognition is the 'constitution of sense'. A formal description of this process will be presented. We use Dempster Shafer's belief calculus to define 'belief' and motivate an Anticipation Principle: 'Put the measurements obtained from the world in such an order that the credibility of your forecasts will be maximized.' From this specification of the basic idea of what physical science ideally strives for, we are able to deduce a frame of reference for the formation of phenomena out of arbitrary sets of measurements. Reality is formed by these 'observable phenomena'. In this emerging reality, we recognize characteristic effects and principles of modern physics: Einstein's Postulate of Relativity, Entanglement, and the Quantum Zeno Effect. The presented view of reality is closely related to the ideas that had been presented hundred years ago by Ernst Mach and which recently J. Anandan generalized in his concept of a 'Relational Reality'

  11. Some aspects of geomagnetically conjugate phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Rycroft, M.J.

    1987-12-01

    Both charged particles and waves convey information about the thermosphere, ionosphere and magnetosphere from the Northern to the Southern Hemisphere and vice versa, along geomagnetic flux tubes.The interhemispheric travel time of electrons or ions, being dependent upon L-value , pitch angle and energy (which may lie between less than or equal to 1 eV and greater than or equal to 1 MeV) may be many hours, ranging down to less than or equal to 1 s. However, the one-hop propagation time for magnetohydrodynamic or whistler mode waves generally lies between 10/sup 2/s and 1 s. Such times, therefore, give the time scales of transient phenomena that are geomagnetically conjugate and of changes in steady-state plasma processes occurring in geomagnetically conjugate regions. Contrasting examples are presented of conjugate physical phenomena, obtained using satellite, rocket, aircraft and ground-based observations; the latter capitalise upon the rather rare disposition of land - rather than ocean - at each end of a geophysically interesting flux tube. Particular attention is paid to the interactions between whistler mode waves and energetic electrons. Geomagnetic, radio, optical and plasma observations, taken together with model computations, provide a wealth of knowledge on conjugate phenomena and their dependence on conditions in the solar wind, substorms, L-value, etc... Finally, some suggestions are made for future lines of research.

  12. Nonlinear CARS measurement of nitrogen vibrational and rotational temperatures behind hypervelocity strong shock wave

    Science.gov (United States)

    Osada, Takashi; Endo, Youichi; Kanazawa, Chikara; Ota, Masanori; Maeno, Kazuo

    2009-02-01

    The hypervelocity strong shock waves are generated, when the space vehicles reenter the atmosphere from space. Behind the shock wave radiative and non-equilibrium flow is generated in front of the surface of the space vehicle. Many studies have been reported to investigate the phenomena for the aerospace exploit and reentry. The research information and data on the high temperature flows have been available to the rational heatproof design of the space vehicles. Recent development of measurement techniques with laser systems and photo-electronics now enables us to investigate the hypervelocity phenomena with greatly advanced accuracy. In this research strong shock waves are generated in low-density gas to simulate the reentry range gas flow with a free-piston double-diaphragm shock tube, and CARS (Coherent Anti-stokes Raman Spectroscopy) measurement method is applied to the hypervelocity flows behind the shock waves, where spectral signals of high space/time resolution are acquired. The CARS system consists of YAG and dye lasers, a spectroscope, and a CCD camera system. We obtain the CARS signal spectrum data by this special time-resolving experiment, and the vibrational and rotational temperatures of N2 are determined by fitting between the experimental spectroscopic profile data and theoretically estimated spectroscopic data.

  13. Nonlinear CARS measurement of nitrogen vibrational and rotational temperatures behind hypervelocity strong shock wave

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Takashi; Endo, Youichi [Graduate Student, Chiba University 1-33 Yayoi, Inage, Chiba, 263-8522 (Japan); Kanazawa, Chikara [Undergraduate, Chiba University 1-33 Yayoi, Inage, Chiba, 63-8522 (Japan); Ota, Masanori; Maeno, Kazuo, E-mail: maeno@faculty.chiba-u.j [Graduate School of Engineering, Chiba University 1-33 Yayoi, Inage, Chiba, 263-8522 (Japan)

    2009-02-01

    The hypervelocity strong shock waves are generated, when the space vehicles reenter the atmosphere from space. Behind the shock wave radiative and non-equilibrium flow is generated in front of the surface of the space vehicle. Many studies have been reported to investigate the phenomena for the aerospace exploit and reentry. The research information and data on the high temperature flows have been available to the rational heatproof design of the space vehicles. Recent development of measurement techniques with laser systems and photo-electronics now enables us to investigate the hypervelocity phenomena with greatly advanced accuracy. In this research strong shock waves are generated in low-density gas to simulate the reentry range gas flow with a free-piston double-diaphragm shock tube, and CARS (Coherent Anti-stokes Raman Spectroscopy) measurement method is applied to the hypervelocity flows behind the shock waves, where spectral signals of high space/time resolution are acquired. The CARS system consists of YAG and dye lasers, a spectroscope, and a CCD camera system. We obtain the CARS signal spectrum data by this special time-resolving experiment, and the vibrational and rotational temperatures of N{sub 2} are determined by fitting between the experimental spectroscopic profile data and theoretically estimated spectroscopic data.

  14. Nonlinear CARS measurement of nitrogen vibrational and rotational temperatures behind hypervelocity strong shock wave

    International Nuclear Information System (INIS)

    Osada, Takashi; Endo, Youichi; Kanazawa, Chikara; Ota, Masanori; Maeno, Kazuo

    2009-01-01

    The hypervelocity strong shock waves are generated, when the space vehicles reenter the atmosphere from space. Behind the shock wave radiative and non-equilibrium flow is generated in front of the surface of the space vehicle. Many studies have been reported to investigate the phenomena for the aerospace exploit and reentry. The research information and data on the high temperature flows have been available to the rational heatproof design of the space vehicles. Recent development of measurement techniques with laser systems and photo-electronics now enables us to investigate the hypervelocity phenomena with greatly advanced accuracy. In this research strong shock waves are generated in low-density gas to simulate the reentry range gas flow with a free-piston double-diaphragm shock tube, and CARS (Coherent Anti-stokes Raman Spectroscopy) measurement method is applied to the hypervelocity flows behind the shock waves, where spectral signals of high space/time resolution are acquired. The CARS system consists of YAG and dye lasers, a spectroscope, and a CCD camera system. We obtain the CARS signal spectrum data by this special time-resolving experiment, and the vibrational and rotational temperatures of N 2 are determined by fitting between the experimental spectroscopic profile data and theoretically estimated spectroscopic data.

  15. Episodic Memory Development: Theory of Mind Is Part of Re-Experiencing Experienced Events

    Science.gov (United States)

    Perner, Josef; Kloo, Daniela; Gornik, Edith

    2007-01-01

    Two experiments with 3 1/2- to 6 1/2-year-old children showed that theory-of-mind development is associated with the growth of episodic memory. Episodic memory was assessed by manipulating informational conditions such that they permit or prevent the formation of episodic memories in terms of re-experiencing the recalled event. Only experienced…

  16. Quasilinear simulations of interplanetary shocks and Earth's bow shock

    Science.gov (United States)

    Afanasiev, Alexandr; Battarbee, Markus; Ganse, Urs; Vainio, Rami; Palmroth, Minna; Pfau-Kempf, Yann; Hoilijoki, Sanni; von Alfthan, Sebastian

    2016-04-01

    We have developed a new self-consistent Monte Carlo simulation model for particle acceleration in shocks. The model includes a prescribed large-scale magnetic field and plasma density, temperature and velocity profiles and a self-consistently computed incompressible ULF foreshock under the quasilinear approximation. Unlike previous analytical treatments, our model is time dependent and takes full account of the anisotropic particle distributions and scattering in the wave-particle interaction process. We apply the model to the problem of particle acceleration at traveling interplanetary (IP) shocks and Earth's bow shock and compare the results with hybrid-Vlasov simulations and spacecraft observations. A qualitative agreement in terms of spectral shape of the magnetic fluctuations and the polarization of the unstable mode is found between the models and the observations. We will quantify the differences of the models and explore the region of validity of the quasilinear approach in terms of shock parameters. We will also compare the modeled IP shocks and the bow shock, identifying the similarities and differences in the spectrum of accelerated particles and waves in these scenarios. The work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA). The Academy of Finland is thanked for financial support. We acknowledge the computational resources provided by CSC - IT Centre for Science Ltd., Espoo.

  17. Diaphragmless shock wave generators for industrial applications of shock waves

    Science.gov (United States)

    Hariharan, M. S.; Janardhanraj, S.; Saravanan, S.; Jagadeesh, G.

    2011-06-01

    The prime focus of this study is to design a 50 mm internal diameter diaphragmless shock tube that can be used in an industrial facility for repeated loading of shock waves. The instantaneous rise in pressure and temperature of a medium can be used in a variety of industrial applications. We designed, fabricated and tested three different shock wave generators of which one system employs a highly elastic rubber membrane and the other systems use a fast acting pneumatic valve instead of conventional metal diaphragms. The valve opening speed is obtained with the help of a high speed camera. For shock generation systems with a pneumatic cylinder, it ranges from 0.325 to 1.15 m/s while it is around 8.3 m/s for the rubber membrane. Experiments are conducted using the three diaphragmless systems and the results obtained are analyzed carefully to obtain a relation between the opening speed of the valve and the amount of gas that is actually utilized in the generation of the shock wave for each system. The rubber membrane is not suitable for industrial applications because it needs to be replaced regularly and cannot withstand high driver pressures. The maximum shock Mach number obtained using the new diaphragmless system that uses the pneumatic valve is 2.125 ± 0.2%. This system shows much promise for automation in an industrial environment.

  18. Women experiencing the intergenerationality of conjugal violence

    Directory of Open Access Journals (Sweden)

    Gilvânia Patrícia do Nascimento Paixão

    2015-10-01

    Full Text Available Objective: to analyze the family relationship, in childhood and adolescence, of women who experience conjugal violence.Method: qualitative study. Interviews were held with 19 women, who were experiencing conjugal violence, and who were resident in a community in Salvador, Bahia, Brazil. The project was approved by the Research Ethics Committee (N. 42/2011.Results: the data was organized using the Discourse of the Collective Subject, identifying the summary central ideas: they witnessed violence between their parents; they suffered repercussions from the violence between their parents: they were angry about the mother's submission to her partner; and they reproduced the conjugal violence. The discourse showed that the women witnessed, in childhood and adolescence, violence between their parents, and were injured both physically and psychologically. As a result of the mother's submission, feelings of anger arose in the children. However, in the adult phase of their own lives, they noticed that their conjugal life resembled that of their parents, reproducing the violence.Conclusion: investment is necessary in strategies designed to break inter-generational violence, and the health professionals are important in this process, as it is a phenomenon with repercussions in health. Because they work in the Family Health Strategy, which focuses on the prevention of harm and illness, health promotion and interdepartmentality, the nurses are essential in the process of preventing and confronting this phenomenon.

  19. Shock wave dynamics derivatives and related topics

    CERN Document Server

    Emanuel, George

    2012-01-01

    "...this monograph develops an esoteric niche within shock wave theory. …treats shock waves from an analytical approach assuming perfect gas. Emanuel has made significant contributions to the theory of shock waves and has selected a number of topics that reflect those contributions."-Shock Waves, 2013.

  20. Shock unsteadiness in a thrust optimized parabolic nozzle

    Science.gov (United States)

    Verma, S. B.

    2009-07-01

    This paper discusses the nature of shock unsteadiness, in an overexpanded thrust optimized parabolic nozzle, prevalent in various flow separation modes experienced during start up {(δ P0 /δ t > 0)} and shut down {(δ P0/δ t The results are based on simultaneously acquired data from real-time wall pressure measurements using Kulite pressure transducers, high-speed schlieren (2 kHz) of the exhaust flow-field and from strain-gauges installed on the nozzle bending tube. Shock unsteadiness in the separation region is seen to increase significantly just before the onset of each flow transition, even during steady nozzle operation. The intensity of this measure ( rms level) is seen to be strongly influenced by relative locations of normal and overexpansion shock, the decrease in radial size of re-circulation zone in the back-flow region, and finally, the local nozzle wall contour. During restricted shock separation, the pressure fluctuations in separation region exhibit periodic characteristics rather than the usually observed characteristics of intermittent separation. The possible physical mechanisms responsible for the generation of flow unsteadiness in various separation modes are discussed. The results are from an experimental study conducted in P6.2 cold-gas subscale test facility using a thrust optimized parabolic nozzle of area-ratio 30.

  1. Job Exposure Matrix for Electric Shock Risks with Their Uncertainties

    Science.gov (United States)

    Vergara, Ximena P.; Fischer, Heidi J.; Yost, Michael; Silva, Michael; Lombardi, David A.; Kheifets, Leeka

    2015-01-01

    We present an update to an electric shock job exposure matrix (JEM) that assigned ordinal electric shocks exposure for 501 occupational titles based on electric shocks and electrocutions from two available data sources and expert judgment. Using formal expert elicitation and starting with data on electric injury, we arrive at a consensus-based JEM. In our new JEM, we quantify exposures by adding three new dimensions: (1) the elicited median proportion; (2) the elicited 25th percentile; and (3) and the elicited 75th percentile of those experiencing occupational electric shocks in a working lifetime. We construct the relative interquartile range (rIQR) based on uncertainty interval and the median. Finally, we describe overall results, highlight examples demonstrating the impact of cut point selection on exposure assignment, and evaluate potential impacts of such selection on epidemiologic studies of the electric work environment. In conclusion, novel methods allowed for consistent exposure estimates that move from qualitative to quantitative measures in this population-based JEM. Overlapping ranges of median exposure in various categories reflect our limited knowledge about this exposure. PMID:25856552

  2. Job Exposure Matrix for Electric Shock Risks with Their Uncertainties

    Directory of Open Access Journals (Sweden)

    Ximena P. Vergara

    2015-04-01

    Full Text Available We present an update to an electric shock job exposure matrix (JEM that assigned ordinal electric shocks exposure for 501 occupational titles based on electric shocks and electrocutions from two available data sources and expert judgment. Using formal expert elicitation and starting with data on electric injury, we arrive at a consensus-based JEM. In our new JEM, we quantify exposures by adding three new dimensions: (1 the elicited median proportion; (2 the elicited 25th percentile; and (3 and the elicited 75th percentile of those experiencing occupational electric shocks in a working lifetime. We construct the relative interquartile range (rIQR based on uncertainty interval and the median. Finally, we describe overall results, highlight examples demonstrating the impact of cut point selection on exposure assignment, and evaluate potential impacts of such selection on epidemiologic studies of the electric work environment. In conclusion, novel methods allowed for consistent exposure estimates that move from qualitative to quantitative measures in this population-based JEM. Overlapping ranges of median exposure in various categories reflect our limited knowledge about this exposure.

  3. Notes on the Prediction of Shock-induced Boundary-layer Separation

    Science.gov (United States)

    Lange, Roy H.

    1953-01-01

    The present status of available information relative to the prediction of shock-induced boundary-layer separation is discussed. Experimental results showing the effects of Reynolds number and Mach number on the separation of both laminar and turbulent boundary layer are given and compared with available methods for predicting separation. The flow phenomena associated with separation caused by forward-facing steps, wedges, and incident shock waves are discussed. Applications of the flat-plate data to problems of separation on spoilers, diffusers, and scoop inlets are indicated for turbulent boundary layers.

  4. Laser Beam Propagation Through Inhomogeneous Media with Shock-Like Profiles: Modeling and Computing

    Science.gov (United States)

    Adamovsky, Grigory; Ida, Nathan

    1997-01-01

    Wave propagation in inhomogeneous media has been studied for such diverse applications as propagation of radiowaves in atmosphere, light propagation through thin films and in inhomogeneous waveguides, flow visualization, and others. In recent years an increased interest has been developed in wave propagation through shocks in supersonic flows. Results of experiments conducted in the past few years has shown such interesting phenomena as a laser beam splitting and spreading. The paper describes a model constructed to propagate a laser beam through shock-like inhomogeneous media. Numerical techniques are presented to compute the beam through such media. The results of computation are presented, discussed, and compared with experimental data.

  5. Stress, Burnout and Culture Shock: An Experiential, Pre-service Approach.

    Science.gov (United States)

    Mungo, Samuel J.

    A carefully-monitored off-campus program for preservice teacher education students can be used as a preventive approach to teacher stress, burnout, and culture shock often experienced by practicing and beginning teachers. Anxiety, caused by a variety of reactions including low self image, threat to security, and fear, is a common element in stress…

  6. Shock Thermodynamic Applied Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Shock Thermodynamic Applied Research Facility (STAR) facility, within Sandia’s Solid Dynamic Physics Department, is one of a few institutions in the world with a...

  7. Target design for shock ignition

    International Nuclear Information System (INIS)

    Schurtz, G; Ribeyre, X; Lafon, M

    2010-01-01

    The conventional approach of laser driven inertial fusion involves the implosion of cryogenic shells of deuterium-tritium ice. At sufficiently high implosion velocities, the fuel ignites by itself from a central hot spot. In order to reduce the risks of hydrodynamic instabilities inherent to large implosion velocities, it was proposed to compress the fuel at low velocity, and ignite the compressed fuel by means of a convergent shock wave driven by an intense spike at the end of the laser pulse. This scheme, known as shock ignition, reduces the risks of shell break-up during the acceleration phase, but it may be impeded by a low coupling efficiency of the laser pulse with plasma at high intensities. This work provides a relationship between the implosion velocity and the laser intensity required to ignite the target by a shock. The operating domain of shock ignition at different energies is described.

  8. Electric Shock Injuries in Children

    Science.gov (United States)

    ... Issues Listen Español Text Size Email Print Share Electric Shock Injuries in Children Page Content ​When the ... comes into direct contact with a source of electricity, the current passes through it, producing what's called ...

  9. Relativistic shocks and particle acceleration

    International Nuclear Information System (INIS)

    Heavens, A.F.

    1988-01-01

    In this paper, we investigate the fluid dynamics of relativistic shock waves, and use the results to calculate the spectral index of particles accelerated by the Fermi process in such shocks. We have calculated the distributions of Fermi-accelerated particles at shocks propagating into cold proton-electron plasma and also cold electron-positron plasma. We have considered two different power spectra for the scattering waves, and find, in contrast to the non-relativistic case, that the spectral index of the accelerated particles depends on the wave power spectrum. On the assumption of thermal equilibrium both upstream and downstream, we present some useful fits for the compression ratio of shocks propagating at arbitrary speeds into gas of any temperature. (author)

  10. Shock wave interaction with turbulence: Pseudospectral simulations

    International Nuclear Information System (INIS)

    Buckingham, A.C.

    1986-01-01

    Shock waves amplify pre-existing turbulence. Shock tube and shock wave boundary layer interaction experiments provide qualitative confirmation. However, shock pressure, temperature, and rapid transit complicate direct measurement. Computational simulations supplement the experimental data base and help isolate the mechanisms responsible. Simulations and experiments, particularly under reflected shock wave conditions, significantly influence material mixing. In these pseudospectral Navier-Stokes simulations the shock wave is treated as either a moving (tracked or fitted) domain boundary. The simulations assist development of code mix models. Shock Mach number and pre-existing turbulence intensity initially emerge as key parameters. 20 refs., 8 figs

  11. The Efficacy of Cognitive Shock

    Science.gov (United States)

    2015-05-21

    way, causing dissonance or cognitive conflict, so that the mental model has to be ‘accommodated’ to the new data. Categories and knowledge have to...The Efficacy of Cognitive Shock A Monograph by MAJ Anthony L. Marston United States Army School of Advanced Military Studies...DATES COVERED (From - To) JUN 2014 – MAY 2015 4. TITLE AND SUBTITLE The Efficacy of Cognitive Shock 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  12. Pressurized Thermal Shock, Pts

    International Nuclear Information System (INIS)

    Boyd, C.

    2008-01-01

    Pressurized Thermal Shock (Pts) refers to a condition that challenges the integrity of the reactor pressure vessel. The root cause of this problem is the radiation embrittlement of the reactor vessel. This embrittlement leads to an increase in the reference temperature for nil ductility transition (RTNDT). RTNDT can increase to the point where the reactor vessel material can loose fracture toughness during overcooling events. The analysis of the risk of having a Pts for a specific plant is a multi-disciplinary problem involving probabilistic risk analysis (PRA), thermal-hydraulic analysis, and ultimately a structural and fracture analysis of the vessel wall. The PRA effort involves the postulation of overcooling events and ultimately leads to an integrated risk analysis. The thermal-hydraulic effort involves the difficult task of predicting the system behavior during a postulated overcooling scenario with a special emphasis on predicting the thermal and mechanic loadings on the reactor pressure vessel wall. The structural and fracture analysis of the reactor vessel wall relies on the thermal-hydraulic conditions as boundary conditions. The US experience has indicated that medium and large diameter primary system breaks dominate the risk of Pts along with scenarios that involve a stuck open valve (and associated system cooldown) that recloses resulting in system re-pressurization while the vessel wall is cool.

  13. Sepsis and septic shock

    Science.gov (United States)

    Hotchkiss, Richard S.; Moldawer, Lyle L.; Opal, Steven M.; Reinhart, Konrad; Turnbull, Isaiah R.; Vincent, Jean-Louis

    2017-01-01

    For more than two decades, sepsis was defined as a microbial infection that produces fever (or hypothermia), tachycardia, tachypnoea and blood leukocyte changes. Sepsis is now increasingly being considered a dysregulated systemic inflammatory and immune response to microbial invasion that produces organ injury for which mortality rates are declining to 15–25%. Septic shock remains defined as sepsis with hyperlactataemia and concurrent hypotension requiring vasopressor therapy, with in-hospital mortality rates approaching 30–50%. With earlier recognition and more compliance to best practices, sepsis has become less of an immediate life-threatening disorder and more of a long-term chronic critical illness, often associated with prolonged inflammation, immune suppression, organ injury and lean tissue wasting. Furthermore, patients who survive sepsis have continuing risk of mortality after discharge, as well as long-term cognitive and functional deficits. Earlier recognition and improved implementation of best practices have reduced in-hospital mortality, but results from the use of immunomodulatory agents to date have been disappointing. Similarly, no biomarker can definitely diagnose sepsis or predict its clinical outcome. Because of its complexity, improvements in sepsis outcomes are likely to continue to be slow and incremental. PMID:28117397

  14. An analytical study of slug impact phenomena

    International Nuclear Information System (INIS)

    Smith, B.L.

    1983-05-01

    Following a HCDA the roof of a fast reactor may be threatened by coolant impact. This article aims to develop at a fundamental level, understanding of the impact process and assess the relevance and magnitude of fluid-structure interaction effects. Reference is made to four 1/30th scale experiments, set up to verify the ideas developed in this work, and to provide quality data for code validation purposes. The impact of a one-dimensional liquid slug on a solid slab is investigated using a simplified form of the Rankine-Hugoniot shock equations derived under the joint assumptions of slight compressibility and small Mach number. Initially the roof slab is considered to be freely supported and of finite thickness. A detailed picture of the shock and expansion wave propagations is built up from the basic equations including the effects of wave reflections at boundaries and wave-wave interactions. Particular attention is paid to the impulse transfer mechanism from the slug as this controls the roof slab acceleration. Bulk fluid cavitation effects are noted. Roof flexural response is then taken into account, together with the effects of the hold-down constraints. It is seen that even very minor structural responses can result in significant mitigation of the impulse loading. Guidelines for the application of the work to HCDA analysis in pool reactor geometries are presented. (Auth.)

  15. Focusing of Shear Shock Waves

    Science.gov (United States)

    Giammarinaro, Bruno; Espíndola, David; Coulouvrat, François; Pinton, Gianmarco

    2018-01-01

    Focusing is a ubiquitous way to transform waves. Recently, a new type of shock wave has been observed experimentally with high-frame-rate ultrasound: shear shock waves in soft solids. These strongly nonlinear waves are characterized by a high Mach number, because the shear wave velocity is much slower, by 3 orders of magnitude, than the longitudinal wave velocity. Furthermore, these waves have a unique cubic nonlinearity which generates only odd harmonics. Unlike longitudinal waves for which only compressional shocks are possible, shear waves exhibit cubic nonlinearities which can generate positive and negative shocks. Here we present the experimental observation of shear shock wave focusing, generated by the vertical motion of a solid cylinder section embedded in a soft gelatin-graphite phantom to induce linearly vertically polarized motion. Raw ultrasound data from high-frame-rate (7692 images per second) acquisitions in combination with algorithms that are tuned to detect small displacements (approximately 1 μ m ) are used to generate quantitative movies of gel motion. The features of shear shock wave focusing are analyzed by comparing experimental observations with numerical simulations of a retarded-time elastodynamic equation with cubic nonlinearities and empirical attenuation laws for soft solids.

  16. Shock compression of synthetic opal

    International Nuclear Information System (INIS)

    Inoue, A; Okuno, M; Okudera, H; Mashimo, T; Omurzak, E; Katayama, S; Koyano, M

    2010-01-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO 4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO 2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  17. Computations of slowly moving shocks

    International Nuclear Information System (INIS)

    Karni, S.; Canic, S.

    1997-01-01

    Computations of slowly moving shocks by shock capturing schemes may generate oscillations are generated already by first-order schemes, but become more pronounced in higher-order schemes which seem to exhibit different behaviors: (i) the first-order upwind (UW) scheme which generates strong oscillations and (ii) the Lax-Friedrichs scheme which appears not to generate any disturbances at all. A key observation is that in the UW case, the numerical viscosity in the shock family vanishes inside the slow shock layer. Simple scaling arguments show the third-order effects on the solution may no longer be neglected. We derive the third-order modified equation for the UW scheme and regard the oscillatory solution as a traveling wave solution of the parabolic modified equation for the perturbation. We then look at the governing equation for the perturbation, which points to a plausible mechanism by which postshock oscillations are generated. It contains a third-order source term that becomes significant inside the shock layer, and a nonlinear coupling term which projects the perturbation on all characteristic fields, including those not associated with the shock family. 5 refs., 8 figs

  18. Shock compression of synthetic opal

    Science.gov (United States)

    Inoue, A.; Okuno, M.; Okudera, H.; Mashimo, T.; Omurzak, E.; Katayama, S.; Koyano, M.

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  19. Shock compression of synthetic opal

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, A; Okuno, M; Okudera, H [Department of Earth Sciences, Kanazawa University Kanazawa, Ishikawa, 920-1192 (Japan); Mashimo, T; Omurzak, E [Shock Wave and Condensed Matter Research Center, Kumamoto University, Kumamoto, 860-8555 (Japan); Katayama, S; Koyano, M, E-mail: okuno@kenroku.kanazawa-u.ac.j [JAIST, Nomi, Ishikawa, 923-1297 (Japan)

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO{sub 4} tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO{sub 2} glass. However, internal silanole groups still remain even at 38.1 GPa.

  20. Transient sensitivity to nisin in cold-shocked Gram negatives.

    Science.gov (United States)

    Boziaris, I S; Adams, M R

    2000-09-01

    Rapid chilling in the presence of nisin caused a dose-dependent reduction in the populations of several Gram-negative bacteria, despite the fact that appreciable structural injury to the outer membrane was not detected. Pseudomonas aeruginosa was most affected, followed by Pseudomonas fragi, Salmonella enteritidis PT4, PT7 and Escherichia coli, respectively. Addition of nisin after the chilling treatment had no effect. The results are ascribed to a transient susceptibility caused by phase changes in the lipids associated with the outer membrane, which are rapidly reversed when the cells return to higher temperatures. Combinations of chilling shock, nisin and EDTA gave much lower reductions of Salmonella and Pseudomonas on chicken skin in comparison with broths. This is attributed to a buffering of the temperature shock experienced by adherent bacteria and binding of the nisin by food particles.

  1. Studies of Novel Quantum Phenomena in Ruthenates

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Zhiqiang

    2011-04-08

    Strongly correlated oxides have been the subject of intense study in contemporary condensed matter physics, and perovskite ruthenates (Sr,Ca)n+1RunO3n+1 have become a new focus in this field. One of important characteristics of ruthenates is that both lattice and orbital degrees of freedom are active and are strongly coupled to charge and spin degrees of freedom. Such a complex interplay of multiple degrees of freedom causes the properties of ruthenates to exhibit a gigantic response to external stimuli under certain circumstances. Magnetic field, pressure, and chemical composition all have been demonstrated to be effective in inducing electronic/magnetic phase transitions in ruthenates. Therefore, ruthenates are ideal candidates for searching for novel quantum phenomena through controlling external parameters. The objective of this project is to search for novel quantum phenomena in ruthenate materials using high-quality single crystals grown by the floating-zone technique, and investigate the underlying physics. The following summarizes our accomplishments. We have focused on trilayered Sr4Ru3O10 and bilayered (Ca1-xSrx)3Ru2O7. We have succeeded in growing high-quality single crystals of these materials using the floating-zone technique and performed systematic studies on their electronic and magnetic properties through a variety of measurements, including resistivity, Hall coefficient, angle-resolved magnetoresistivity, Hall probe microscopy, and specific heat. We have also studied microscopic magnetic properties for some of these materials using neutron scattering in collaboration with Los Alamos National Laboratory. We have observed a number of unusual exotic quantum phenomena through these studies, such as an orbital selective metamagnetic transition, bulk spin valve effect, and a heavy-mass nearly ferromagnetic state with a surprisingly large Wilson ratio. Our work has also revealed underlying physics of these exotic phenomena. Exotic phenomena of correlated

  2. In vessel core melt progression phenomena

    International Nuclear Information System (INIS)

    Courtaud, M.

    1993-01-01

    For all light water reactor (LWR) accidents, including the so called severe accidents where core melt down can occur, it is necessary to determine the amount and characteristics of fission products released to the environment. For existing reactors this knowledge is used to evaluate the consequences and eventual emergency plans. But for future reactors safety authorities demand decrease risks and reactors designed in such a way that fission products are retained inside the containment, the last protective barrier. This requires improved understanding and knowledge of all accident sequences. In particular it is necessary to be able to describe the very complex phenomena occurring during in vessel core melt progression because they will determine the thermal and mechanical loads on the primary circuit and the timing of its rupture as well as the fission product source term. On the other hand, in case of vessel failure, knowledge of the physical and chemical state of the core melt will provide the initial conditions for analysis of ex-vessel core melt progression and phenomena threatening the containment. Finally a good understanding of in vessel phenomena will help to improve accident management procedures like Emergency Core Cooling System water injection, blowdown and flooding of the vessel well, with their possible adverse effects. Research and Development work on this subject was initiated a long time ago and is still in progress but now it must be intensified in order to meet the safety requirements of the next generation of reactors. Experiments, limited in scale, analysis of the TMI 2 accident which is a unique source of global information and engineering judgment are used to establish and assess physical models that can be implemented in computer codes for reactor accident analysis

  3. BWR core melt progression phenomena: Experimental analyses

    International Nuclear Information System (INIS)

    Ott, L.J.

    1992-01-01

    In the BWR Core Melt in Progression Phenomena Program, experimental results concerning severe fuel damage and core melt progression in BWR core geometry are used to evaluate existing models of the governing phenomena. These include control blade eutectic liquefaction and the subsequent relocation and attack on the channel box structure; oxidation heating and hydrogen generation; Zircaloy melting and relocation; and the continuing oxidation of zirconium with metallic blockage formation. Integral data have been obtained from the BWR DF-4 experiment in the ACRR and from BWR tests in the German CORA exreactor fuel-damage test facility. Additional integral data will be obtained from new CORA BWR test, the full-length FLHT-6 BWR test in the NRU test reactor, and the new program of exreactor experiments at Sandia National Laboratories (SNL) on metallic melt relocation and blockage formation. an essential part of this activity is interpretation and use of the results of the BWR tests. The Oak Ridge National Laboratory (ORNL) has developed experiment-specific models for analysis of the BWR experiments; to date, these models have permitted far more precise analyses of the conditions in these experiments than has previously been available. These analyses have provided a basis for more accurate interpretation of the phenomena that the experiments are intended to investigate. The results of posttest analyses of BWR experiments are discussed and significant findings from these analyses are explained. The ORNL control blade/canister models with materials interaction, relocation and blockage models are currently being implemented in SCDAP/RELAP5 as an optional structural component

  4. Suprasensory phenomena in those with a bipolar disorder.

    Science.gov (United States)

    Parker, Gordon; Paterson, Amelia; Romano, Mia; Granville Smith, Isabelle

    2018-03-01

    To increase awareness of the sensory changes experienced during hypo/manic and depressive states by those with a bipolar disorder and determine if the prevalence of such features is similar across differing bipolar sub-types. We interviewed 66 patients who acknowledged sensory changes during hypo/manic states. They were allocated to bipolar I, bipolar II and soft bipolar diagnostic categories and the prevalence of 10 differing sensory changes was quantified during hypo/manic and depressive phases. Bipolar I patients were just as likely, if not more likely, to report suprasensory changes which typically involved enhancement of senses during hypo/manic phases and muting or blunting during depressive phases. The high prevalence of changes in intuition, empathy, appreciation of danger and predictive capacities suggests that these are more part of the intrinsic bipolar mood domain states and not necessarily suprasensory, while changes in primary senses of smell, taste, vision, touch and hearing appear to more commonly define the suprasensory domain. It is important for clinicians and patients with a bipolar disorder to be aware of non-psychotic, suprasensory phenomena. Identification of such features may aid diagnosis and also explain the recognised increased creativity in those with a bipolar condition.

  5. Analysis of vortex phenomena in PWRs at reduced inventory conditions

    International Nuclear Information System (INIS)

    Waldrep, G.W.; Field, R.W.

    1990-01-01

    Several recent events have occurred in pressurized water reactors in which shutdown cooling flow has been lost. This has resulted in considerable concern in the industry with operation at or near mid-loop conditions during shutdown operations. Although operation at mid-loop conditions can be minimized, it cannot be totally eliminated without fully off-loading the core. The primary concern is that at reduced inventory conditions and with high flow rates [>15 m 3 /min (4,000 gal/min)], air entrainment due to vortexing can occur. Although the Palo Verde Nuclear Generating Station (PVNGS) (operated by Arizona Public Service) never experienced an actual loss of shutdown cooling, several instances occurred in which evidence of air entrainment was observed. These indications include pump amp oscillations, flow noises, bubbles in the tygon-level monitoring system, and discharge flow/pressure oscillations. These occurrences as well as the NRC's concerns heightened Arizona Public Service's desire to thoroughly understand the actual flow characteristics and vortex phenomena in a Combustion Engineering System 80 pressurized water reactor

  6. ACCIDENT PHENOMENA OF RISK IMPORTANCE PROJECT - Continued RESEARCH CONCERNING SEVERE ACCIDENT PHENOMENA AND MANAGEMENT IN Sweden

    International Nuclear Information System (INIS)

    Rolandson, S.; Mueller, F.; Loevenhielm, G.

    1997-01-01

    Since 1988 all reactors in Sweden have mitigating measures, such as filtered vents, implemented. In parallel with the work of implementing these measures, a cooperation effort (RAMA projects) between the Swedish utilities and the Nuclear Power Inspectorate was performed to acquire sufficient knowledge about severe accident research work. The on-going project has the name Accident Phenomena of Risk Importance 3. In this paper, we will give background information about severe accident management in Sweden. In the Accident Phenomena of Risk Importance 3 project we will focus on the work concerning coolability of melted core in lower plenum which is the main focus of the In-vessel Coolability Task Group within the Accident Phenomena of Risk Importance 3 project. The Accident Phenomena of Risk Importance 3 project has joined on international consortium and the in-vessel cooling experiments are performed by Fauske and Associates, Inc. in Burr Ridge, Illinois, United States America, Sweden also intends to do one separate experiment with one instrument penetration we have in Swedish/Finnish BWR's. Other parts of the Accident Phenomena of Risk Importance 3 project, such as support to level 2 studies, the research at Royal Institute of Technology and participation in international programs, such as Cooperative Severe Accident Research Program, Advanced Containment Experiments and PHEBUS will be briefly described in the paper

  7. Jets and large Psub(T) phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, D. S.

    1980-07-01

    Jets have been observed in hadron-hadron collisions and e/sup +/e/sup -/ annihilation at high energies. An attempt is made to explain the mechanism for the production of jets. The mechanism of quark-fragmentation is described with illustrations. Basic concepts and assumptions are used to study the distribution of quarks and gluons in a hadron. Quark and gluon decay distributions, and the transverse momentum distributions of quarks and gluons, Monte-Carlo methods in the study of jets, large Psub(T) phenomena in hadrons, QCD effects in hadronization of quark jets are discussed.

  8. Quenching phenomena in natural circulation loop

    International Nuclear Information System (INIS)

    Umekawa, Hisashi; Ozawa, Mamoru; Ishida, Naoki

    1995-01-01

    Quenching phenomena has been investigated experimentally using circulation loop of liquid nitrogen. During the quenching under natural circulation, the heat transfer mode changes from film boiling to nucleate boiling, and at the same time flux changes with time depending on the vapor generation rate and related two-phase flow characteristics. Moreover, density wave oscillations occur under a certain operating condition, which is closely related to the dynamic behavior of the cooling curve. The experimental results indicates that the occurrence of the density wave oscillation induces the deterioration of effective cooling of the heat surface in the film and the transition boiling regions, which results in the decrease in the quenching velocity

  9. Modeling in transport phenomena a conceptual approach

    CERN Document Server

    Tosun, Ismail

    2007-01-01

    Modeling in Transport Phenomena, Second Edition presents and clearly explains with example problems the basic concepts and their applications to fluid flow, heat transfer, mass transfer, chemical reaction engineering and thermodynamics. A balanced approach is presented between analysis and synthesis, students will understand how to use the solution in engineering analysis. Systematic derivations of the equations and the physical significance of each term are given in detail, for students to easily understand and follow up the material. There is a strong incentive in science and engineering to

  10. General unifying features of controlled quantum phenomena

    International Nuclear Information System (INIS)

    Pechen, Alexander; Brif, Constantin; Wu, Rebing; Chakrabarti, Raj; Rabitz, Herschel

    2010-01-01

    Many proposals have been put forth for controlling quantum phenomena, including open-loop, adaptive feedback, and real-time feedback control. Each of these approaches has been viewed as operationally, and even physically, distinct from the others. This work shows that all such scenarios inherently share the same fundamental control features residing in the topology of the landscape relating the target physical observable to the applied controls. This unified foundation may provide a basis for development of hybrid control schemes that would combine the advantages of the existing approaches to achieve the best overall performance.

  11. Simple models of equilibrium and nonequilibrium phenomena

    International Nuclear Information System (INIS)

    Lebowitz, J.L.

    1987-01-01

    This volume consists of two chapters of particular interest to researchers in the field of statistical mechanics. The first chapter is based on the premise that the best way to understand the qualitative properties that characterize many-body (i.e. macroscopic) systems is to study 'a number of the more significant model systems which, at least in principle are susceptible of complete analysis'. The second chapter deals exclusively with nonequilibrium phenomena. It reviews the theory of fluctuations in open systems to which they have made important contributions. Simple but interesting model examples are emphasised

  12. Advances in modelling of condensation phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Zaltsgendler, E. [Ontario Hydro Nuclear, Toronto (Canada); Hanna, B. [Atomic Energy of Canada Limited, Pinawa, Manitoba (Canada)

    1997-07-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

  13. Cooperative phenomena in flows; Poster abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Loekseth, Trine (ed.)

    2011-05-15

    The objective of this 'Geilo School' was to bring together researchers with various interests and background including theoretical experimental physicists, material scientists and molecular biologists to identify and discuss areas where synergism between these disciplines may be most fruitfully applied to the study of various aspects of 'Cooperative phenomena in flows'. There were altogether 21 lecturers at the School with about 80 participants from 19 countries. This was the 21. Geilo School held biannually since the first one in I971. Reference to the earlier Geilo Schools 1971-2009 may be found here: http://www.ife.no/departments/physics/projects/geilo (Author)

  14. Current position on severe accident phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Henry, Robert E [Fauske and Associates, Inc., Burr Ridge, IL (United States)

    2004-07-01

    The phenomena addressed in this lecture are: in-vessel and ex-vessel hydrogen generation; in-vessel and in-containment natural circulation, steam explosions, direct containment heating, core-concrete interaction; debris coolability, containment strength/failure. The following events were modeled: axial and radial power distribution, two-phase level in the core, steam generation in covered section, decay heat generation, convection to gas, cladding oxidation, cold ballooning and rupture, natural circulation between the core and upper plenum, hydrogen generation, core meltdown, reflooding. Differences between PWR and BWR type reactors.

  15. Current position on severe accident phenomena

    International Nuclear Information System (INIS)

    Henry, Robert E.

    2004-01-01

    The phenomena addressed in this lecture are: in-vessel and ex-vessel hydrogen generation; in-vessel and in-containment natural circulation, steam explosions, direct containment heating, core-concrete interaction; debris coolability, containment strength/failure. The following events were modeled: axial and radial power distribution, two-phase level in the core, steam generation in covered section, decay heat generation, convection to gas, cladding oxidation, cold ballooning and rupture, natural circulation between the core and upper plenum, hydrogen generation, core meltdown, reflooding. Differences between PWR and BWR type reactors

  16. Cooperative phenomena in flows; Poster abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Loekseth, Trine [ed.

    2011-05-15

    The objective of this 'Geilo School' was to bring together researchers with various interests and background including theoretical experimental physicists, material scientists and molecular biologists to identify and discuss areas where synergism between these disciplines may be most fruitfully applied to the study of various aspects of 'Cooperative phenomena in flows'. There were altogether 21 lecturers at the School with about 80 participants from 19 countries. This was the 21. Geilo School held biannually since the first one in I971. Reference to the earlier Geilo Schools 1971-2009 may be found here: http://www.ife.no/departments/physics/projects/geilo (Author)

  17. Critical phenomena and renormalization group transformations

    International Nuclear Information System (INIS)

    Castellani, C.; Castro, C. di

    1980-01-01

    Our main goal is to guide the reader to find out the common rational behind the various renormalization procedures which have been proposed in the last ten years. In the first part of these lectures old arguments on universality and scaling will be briefly recalled. To our opinion these introductory remarks allow one to stress the physical origin of the two majore renormalization procedures, which have been used in the theory of critical phenomena: the Wilson and the field theoretic approach. All the general properties of a ''good'' renormalization transformation will also come out quite naturally. (author)

  18. Phenomena and parameters important to burnup credit

    International Nuclear Information System (INIS)

    Parks, C.V.; Dehart, M.D.; Wagner, J.C.

    2001-01-01

    Since the mid-1980s, a significant number of studies have been directed at understanding the phenomena and parameters important to implementation of burnup credit in out-of-reactor applications involving pressurized-water- reactor (PWR) spent fuel. The efforts directed at burnup credit involving boiling-water-reactor (BWR) spent fuel have been more limited. This paper reviews the knowledge and experience gained from work performed in the United States and other countries in the study of burnup credit. Relevant physics and analysis phenomenon are identified, and an assessment of their importance to burnup credit implementation for transport and dry cask storage is given. (author)

  19. Chalcogenides Metastability and Phase Change Phenomena

    CERN Document Server

    Kolobov, Alexander V

    2012-01-01

    A state-of-the-art description of metastability observed in chalcogenide alloys is presented with the accent on the underlying physics. A comparison is made between sulphur(selenium)-based chalcogenide glasses, where numerous photo-induced phenomena take place entirely within the amorphous phase, and tellurides where a reversible crystal-to-amorphous phase-change transformation is a major effect. Applications of metastability in devices¿optical memories and nonvolatile electronic phase-change random-access memories among others are discussed, including the latest trends. Background material essential for understanding current research in the field is also provided.

  20. Nanoscale and microscale phenomena fundamentals and applications

    CERN Document Server

    Khandekar, Sameer

    2015-01-01

    The book is an outcome of research work in the areas of nanotechnology, interfacial science, nano- and micro-fluidics and manufacturing, soft matter, and transport phenomena at nano- and micro-scales. The contributing authors represent prominent research groups from Indian Institute of Technology Bombay, Indian Institute of Technology Kanpur and Indian Institute of Science, Bangalore. The book has 13 chapters and the entire work presented in the chapters is based on research carried out over past three years. The chapters are designed with number of coloured illustrations, figures and tables. The book will be highly beneficial to academicians as well as industrial professionals working in the mentioned areas.

  1. Advances in modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Liu, W.S.; Zaltsgendler, E.; Hanna, B.

    1997-01-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described

  2. Layered phenomena in the mesopause region

    Science.gov (United States)

    Plane, J. M. C.; Bailey, S. M.; Baumgarten, G.; Rapp, M.

    2015-05-01

    This special issue of the Journal of Atmospheric and Solar-Terrestrial Physics comprises a collection of papers which were mostly presented at the 11th Layered Phenomena in the Mesopause Region (LPMR) Workshop, held at the University of Leeds between 29th July 2013 and 1st August 2013. The topics covered at the workshop included atmospheric dynamics, mesospheric ice clouds, meteoric metal layers, meteoric smoke particles, and airglow layers. There was also a session on the potential of planned sub-orbital spacecraft for making measurements in the mesosphere and lower thermosphere (MLT).

  3. Micro- and nanoscale phenomena in tribology

    CERN Document Server

    Chung, Yip-Wah

    2011-01-01

    Drawn from presentations at a recent National Science Foundation Summer Institute on Nanomechanics, Nanomaterials, and Micro/Nanomanufacturing, Micro- and Nanoscale Phenomena in Tribology explores the convergence of the multiple science and engineering disciplines involved in tribology and the connection from the macro to nano world. Written by specialists from computation, materials science, mechanical engineering, surface physics, and chemistry, each chapter provides up-to-date coverage of both basic and advanced topics and includes extensive references for further study.After discussing the

  4. Quenching phenomena in natural circulation loop

    Energy Technology Data Exchange (ETDEWEB)

    Umekawa, Hisashi; Ozawa, Mamoru [Kansai Univ., Osaka (Japan); Ishida, Naoki [Daihatsu Motor Company, Osaka (Japan)

    1995-09-01

    Quenching phenomena has been investigated experimentally using circulation loop of liquid nitrogen. During the quenching under natural circulation, the heat transfer mode changes from film boiling to nucleate boiling, and at the same time flux changes with time depending on the vapor generation rate and related two-phase flow characteristics. Moreover, density wave oscillations occur under a certain operating condition, which is closely related to the dynamic behavior of the cooling curve. The experimental results indicates that the occurrence of the density wave oscillation induces the deterioration of effective cooling of the heat surface in the film and the transition boiling regions, which results in the decrease in the quenching velocity.

  5. Critical Phenomena Associated with Boson Stars

    OpenAIRE

    Hawley, Scott H.; Choptuik, Matthew W.

    2001-01-01

    We present a brief synopsis of related work (gr-qc/0007039), describing a study of black hole threshold phenomena for a self-gravitating, massive complex scalar field in spherical symmetry. We construct Type I critical solutions dynamically by tuning a one-parameter family of initial data consisting of a boson star and a massless real scalar field, and numerically evolving this data. The resulting critical solutions appear to correspond to boson stars on the unstable branch, as we show via co...

  6. Shock Deformation and Volcanism across the Cretaceous - Transition.

    Science.gov (United States)

    Huffman, Alan Royce

    1990-01-01

    The cause of the Cretaceous-Tertiary (K/T) transition remains one of the most controversial scientific topics in the geosciences. Geological and geophysical evidence associated with the K/T boundary have been used to argue that the extinctions were caused by meteor impact or volcanism. The goal of this study was to assess the viability of a volcanic model for the K/T transition. Comparison of natural and experimentally-shocked quartz and feldspar using optical and transmission electron microscopy (TEM) revealed that the optical and statistical character of shock-induced microstructures in volcanic rocks are different from both classic impact microstructures, and from the Raton K/T samples. A series of 31 high-explosive (HE) shock-recovery experiments at pressures to 25 GPa and temperatures to 750^circC were completed on samples of granite and quartzite. TEM and optical microscopy reveal that pre-shock temperature and pulse duration have a first-order effect on the development of shock-induced microstructures in quartz and feldspar. Application of the experimental results to natural shock-induced microstructures indicates that the volcanic microstructures are probably produced at elevated temperatures and shock pressures that do not exceed 15 GPa. The results also suggest that the Raton K/T deposits were produced at pressures below about 25 GPa. Analysis of samples from the K/T transition at DSDP Site 527 and correlations between biostratigraphy, isotopes, and the data from this study suggest that the decline in marine productivity over an extended period of time may be due to climate changes induced by basaltic volcanism. The eruption of the Deccan Traps is a viable mechanism for the K/T extinctions, and the correlation of flood basalts with every major biotic crisis in the last 250 Ma supports the link between these two phenomena. Eruption of flood basalts enriched in F, Cl, CO_2 , and SO_2, could disrupt the terrestrial ecosystem, and could produce effects

  7. A microstructural investigation of shock-loading effects in FCC materials

    Science.gov (United States)

    Rohatgi, Aashish

    A systematic investigation of the influence of stacking fault energy (SFE) on shock loading effects in Cu and Cu-Al alloys has been conducted. Shock deformation in many materials is known to produce dislocation density in excess of that produced by quasi-static deformation to an equivalent strain. If the shock pressure is high enough and/or the SFE of the material is low enough, shock loading may also generate deformation twins. Both dislocations and deformation twins contribute to the post-shock strength of the material. Cu and a series of Cu-Al alloys with increasing Al contents were shock deformed at pressures of 10 and 35 GPa with a pulse duration of 1 mus each. The materials showed shock-strengthening which decreased with decreasing SFE. The twin component of post-shock strength was found to increase with decreasing SFE, while the dislocation component concurrently decreased. Since slip and twinning are competing phenomena, a greater propensity for twinning at lower SFE results in the shock-strain in low SFE materials being accommodated preferentially by twinning than by slip. Thus, the dislocation density in a twinned material is lower than if the deformation was accommodated entirely by slip. Additionally, as low SFE hinders cross-slip, a low SFE material shows a large Bauschinger effect and is unable to store additional dislocation line-length resulting in a lower dislocation density than in a similarly deformed high SFE material. The stored energy of materials shock-deformed to the same peak shock pressure was measured using differential scanning calorimetry (DSC) and was found to decrease with decreasing SFE. Using the stored energy data and a known value of energy per unit length of a dislocation, the stored dislocation density was found to decrease with decreasing SFE. It is suggested that the deformation twin boundaries are not as effective strengtheners, as dislocation-dislocation interactions. As a result of the lower strengthening efficiency but a

  8. The discovery of nuclear compression phenomena in relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Schmidt, H.R.

    1991-01-01

    This article has attempted to review more than 15 years of research on shock compression phenomena, which is closely related to the goal of determining the nuclear EOS. Exciting progress has been made in this field over the last years and the fundamental physics of relativistic heavy ion-collisions has been well established. Overwhelming experimental evidence for the existence of shock compression has been extracted from the data. While early, inclusive measurements had been rather inconclusive, the advent of 4π-detectors like the GSI-LBL Plastic Ball had enabled the outstanding discovery of collective flow effects, as they were predicted by fluid-dynamical calculations. The particular case of conical Mach shock waves, anticipated for asymmetric collisions, has not been observed. What are the reasons? Surprisingly, the maximum energy of 2.1 GeV/nucleon for heavy ions at the BEVALAC had been found to be too low for Mach shock waves to occur. The small 20 Ne-nucleus is stopped in the heavy Au target. A Mach cone, however, if it had developed in the early stage of the collision will be wiped out by thermal motion in the process of slowing the projectile down to rest. A comparison of the data with models hints towards a rather hard EOS, although a soft one cannot be excluded definitively. A quantitative extraction is aggravated by a number in-medium and final-state effects which influence the calculated observables in a similar fashion as different choices of an EOS. Thus, as of now, the precise knowledge of the EOS of hot and dense matter is still an open question and needs further investigation. (orig.)

  9. Views on Values Education: From Teacher Candidates to Experienced Teachers

    Science.gov (United States)

    Iscan, Canay Demirhan

    2015-01-01

    This study aimed to identify the views of experienced class teachers and class teacher candidates on values education. It conducted standard open-ended interviews with experienced class teachers and teacher candidates. The study group comprised 9 experienced class teachers from different socio-economic levels and 9 teacher candidates with…

  10. Nano-material aspects of shock absorption in bone joints.

    Science.gov (United States)

    Tributsch, H; Copf, F; Copf, P; Hindenlang, U; Niethard, F U; Schneider, R

    2010-01-01

    This theoretical study is based on a nano-technological evaluation of the effect of pressure on the composite bone fine structure. It turned out, that the well known macroscopic mechano-elastic performance of bones in combination with muscles and tendons is just one functional aspect which is critically supported by additional micro- and nano- shock damping technology aimed at minimising local bone material damage within the joints and supporting spongy bone material. The identified mechanisms comprise essentially three phenomena localised within the three-dimensional spongy structure with channels and so called perforated flexible tensulae membranes of different dimensions intersecting and linking them. Kinetic energy of a mechanical shock may be dissipated within the solid-liquid composite bone structure into heat via the generation of quasi-chaotic hydromechanic micro-turbulence. It may generate electro-kinetic energy in terms of electric currents and potentials. And the resulting specific structural and surface electrochemical changes may induce the compressible intra-osseal liquid to build up pressure dependent free chemical energy. Innovative bone joint prostheses will have to consider and to be adapted to the nano-material aspects of shock absorption in the operated bones.

  11. Migration and sorption phenomena in packaged foods.

    Science.gov (United States)

    Gnanasekharan, V; Floros, J D

    1997-10-01

    Rapidly developing analytical capabilities and continuously evolving stringent regulations have made food/package interactions a subject of intense research. This article focuses on: (1) the migration of package components such as oligomers and monomers, processing aids, additives, and residual reactants in to packaged foods, and (2) sorption of food components such as flavors, lipids, and moisture into packages. Principles of diffusion and thermodynamics are utilized to describe the mathematics of migration and sorption. Mathematical models are developed from first principles, and their applicability is illustrated using numerical simulations and published data. Simulations indicate that available models are system (polymer-penetrant) specific. Furthermore, some models best describe the early stages of migration/sorption, whereas others should be used for the late stages of these phenomena. Migration- and/or sorption-related problems with respect to glass, metal, paper-based and polymeric packaging materials are discussed, and their importance is illustrated using published examples. The effects of migrating and absorbed components on food safety, quality, and the environment are presented for various foods and packaging materials. The impact of currently popular packaging techniques such as microwavable, ovenable, and retortable packaging on migration and sorption are discussed with examples. Analytical techniques for investigating migration and sorption phenomena in food packaging are critically reviewed, with special emphasis on the use and characteristics of food-simulating liquids (FSLs). Finally, domestic and international regulations concerning migration in packaged foods, and their impact on food packaging is briefly presented.

  12. Study of catalytic phenomena in radiation chemistry

    International Nuclear Information System (INIS)

    Dran, J.C.

    1965-01-01

    Two phenomena have been studied: the action of γ rays from radio-cobalt on the adsorption and catalytic properties of ZnO and NiO in. relationship with the heterogeneous oxidation of CO, and the homogeneous catalysis by OsO 4 of the oxidation of various aqueous phase solutes by the same radiation. The prior irradiation of ZnO and of NiO does not modify their catalytic activity but generally increases the adsorption energy of -the gases CO and O 2 . The influence of the radiations appears to be connected with the presence of traces of water on ZnO and of an excess of oxygen on NiO. Osmium tetroxide which is not degraded by irradiation in acid solution, accelerates the radiolytic oxidation of certain compounds (Te IV , Pt 11 , As 111 ) in the presence of oxygen, as a result of its sensitizing effect on the oxidation by H 2 O 2 . In the case of phosphites on the other hand, OsO 4 has a protecting action under certain conditions of acidity and may suppress entirely the chain reaction which characterizes the oxidation of this solute byγ rays. A general mechanism is proposed for these phenomena. The rate constant for the OsO 4 + HO 2 reaction is calculated to be 5.7 x 10 5 l.mol -1 . sec -1 . (author) [fr

  13. WHC natural phenomena hazards mitigation implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    Conrads, T.J.

    1996-09-11

    Natural phenomena hazards (NPH) are unexpected acts of nature which pose a threat or danger to workers, the public or to the environment. Earthquakes, extreme winds (hurricane and tornado),snow, flooding, volcanic ashfall, and lightning strike are examples of NPH at Hanford. It is the policy of U.S. Department of Energy (DOE) to design, construct and operate DOE facilitiesso that workers, the public and the environment are protected from NPH and other hazards. During 1993 DOE, Richland Operations Office (RL) transmitted DOE Order 5480.28, ``Natural Phenomena Hazards Mitigation,`` to Westinghouse Hanford COmpany (WHC) for compliance. The Order includes rigorous new NPH criteria for the design of new DOE facilities as well as for the evaluation and upgrade of existing DOE facilities. In 1995 DOE issued Order 420.1, ``Facility Safety`` which contains the same NPH requirements and invokes the same applicable standards as Order 5480.28. It will supersede Order 5480.28 when an in-force date for Order 420.1 is established through contract revision. Activities will be planned and accomplished in four phases: Mobilization; Prioritization; Evaluation; and Upgrade. The basis for the graded approach is the designation of facilities/structures into one of five performance categories based upon safety function, mission and cost. This Implementation Plan develops the program for the Prioritization Phase, as well as an overall strategy for the implemention of DOE Order 5480.2B.

  14. Unsteady phenomena in the edge tone

    International Nuclear Information System (INIS)

    Paal, G.; Vaik, I.

    2007-01-01

    Despite its geometrical simplicity, the edge tone displays a remarkably complex behaviour. A plane jet oscillates around the wedge-shaped object with a relatively stable frequency and under certain circumstances emits an audible tone. This configuration plays a central role in the sound production of several wind instruments but occurs in industrial situations too. The flow exhibits various interesting nonlinear phenomena reported in the literature which are not entirely explained. In this paper, detailed high precision numerical simulations of the flow are reported under various conditions. Several phenomena are reproduced in agreement with the literature such as the existence of 'stages', the dependence of oscillation frequency on the outflow velocity and the orifice-edge distance within one stage, the pressure distribution on the edge surface, etc. A criterion for the appropriate time step for constant accuracy has been derived. The location of force action is surprisingly stable; it remains in a very narrow region of the wedge surface independently of the Reynolds number and the orifice-edge distance but it is much further behind the edge tip than reported in the literature. The various stages can coexist in different ways: jumping back and forth between stages or being superposed on each other. Regardless of the form, the first stage continues to be dominant even when the second and third stage appears. The question of disturbance propagation velocity and disturbance wavelength is also investigated. The development of higher harmonics of a single stage along the orifice-edge tip distance is presented

  15. Augmented Visual Experience of Simulated Solar Phenomena

    Science.gov (United States)

    Tucker, A. O., IV; Berardino, R. A.; Hahne, D.; Schreurs, B.; Fox, N. J.; Raouafi, N.

    2017-12-01

    The Parker Solar Probe (PSP) mission will explore the Sun's corona, studying solar wind, flares and coronal mass ejections. The effects of these phenomena can impact the technology that we use in ways that are not readily apparent, including affecting satellite communications and power grids. Determining the structure and dynamics of corona magnetic fields, tracing the flow of energy that heats the corona, and exploring dusty plasma near the Sun to understand its influence on solar wind and energetic particle formation requires a suite of sensors on board the PSP spacecraft that are engineered to observe specific phenomena. Using models of these sensors and simulated observational data, we can visualize what the PSP spacecraft will "see" during its multiple passes around the Sun. Augmented reality (AR) technologies enable convenient user access to massive data sets. We are developing an application that allows users to experience environmental data from the point of view of the PSP spacecraft in AR using the Microsoft HoloLens. Observational data, including imagery, magnetism, temperature, and density are visualized in 4D within the user's immediate environment. Our application provides an educational tool for comprehending the complex relationships of observational data, which aids in our understanding of the Sun.

  16. Syntactic Idioms and Precedent Phenomena: Intersection Zones

    Directory of Open Access Journals (Sweden)

    Hanna Sytar

    2016-08-01

    Full Text Available Background: One examined mainly structural and semantic features of syntactic idioms so far. The pragmatic dimension of these original units that are on the verge of syntax and phraseology, has not been highlighted properly in the scientific literature, so it needs theoretical understanding. The combination of syntactic idiom and phraseological phenomenon refers to the communication techniques impacting on message recipient. Purpose: to analyze the intersection zones of syntactic idioms and precedent phenomena. Results: Analysis of the collected factual material allows to distinguish two areas of interpenetration of syntactic idioms and precedent units: 1 construction of expression according to the phraseologized model, within which the position of variable component is filled by the precedent name or precedent expression; 2 the model of sentence itself is precedent, and lexical content does not comply with generally known one that does not affect on understanding of model content by recipient. With a combination of syntactic idiom and precedent phenomena speakers provide drawing of recipients’ attention, carry out a hidden influence on them, express their own attitude to the realities, so that perform phatic, manipulative and expressive-evaluative functions. The modifications and transformations of precedent expressions and names appeared to be regular in such interpenetrations. Discussion: The obtained results reflect the general trend towards transform (transformation, modification, variation, etc. of precedent, as well as phraseological units, and can be used for the analysis of patterns of their formation and modifications. Further research phase implies tracing patterns of syntactic idioms combination with other means of expressive syntax.

  17. Laboratory simulation of space plasma phenomena*

    Science.gov (United States)

    Amatucci, B.; Tejero, E. M.; Ganguli, G.; Blackwell, D.; Enloe, C. L.; Gillman, E.; Walker, D.; Gatling, G.

    2017-12-01

    Laboratory devices, such as the Naval Research Laboratory's Space Physics Simulation Chamber, are large-scale experiments dedicated to the creation of large-volume plasmas with parameters realistically scaled to those found in various regions of the near-Earth space plasma environment. Such devices make valuable contributions to the understanding of space plasmas by investigating phenomena under carefully controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. By working in collaboration with in situ experimentalists to create realistic conditions scaled to those found during the observations of interest, the microphysics responsible for the observed events can be investigated in detail not possible in space. To date, numerous investigations of phenomena such as plasma waves, wave-particle interactions, and particle energization have been successfully performed in the laboratory. In addition to investigations such as plasma wave and instability studies, the laboratory devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this presentation, we will describe several examples of the laboratory investigation of space plasma waves and instabilities and diagnostic development. *This work supported by the NRL Base Program.

  18. Modelling of thermohydraulic emergency core cooling phenomena

    International Nuclear Information System (INIS)

    Yadigaroglu, G.; Andreani, M.; Lewis, M.J.

    1990-10-01

    The codes used in the early seventies for safety analysis and licensing were based either on the homogeneous model of two-phase flow or on the so-called separate-flow models, which are mixture models accounting, however, for the difference in average velocity between the two phases. In both cases the behavior of the mixture is prescribed a priori as a function of local parameters such as the mass flux and the quality. The modern best-estimate codes used for analyzing LWR LOCA's and transients are often based on a two-fluid or 6-equation formulation of the conservation equations. In this case the conservation equations are written separately for each phase; the mixture is allowed to evolve on its own, governed by the interfacial exchanges of mass, momentum and energy between the phases. It is generally agreed that such relatively sophisticated 6-equation formulations of two-phase flow are necessary for the correct modelling of a number of phenomena and situations arising in LWR accidental situations. They are in particular indispensible for the analysis of stratified or countercurrent flows and of situations in which large departures from thermal and velocity equilibrium exist. This report will be devoted to a discussion of the need for, the capacity and the limitations of the two-phase flow models (with emphasis on the 6-equation formulations) in modelling these two-phase flow and heat transfer phenomena and/or different core cooling situations. 18 figs., 1 tab., 72 refs

  19. [Is the brain the creator of psychic phenomena or is a paradigm shift inevitable?].

    Science.gov (United States)

    Bonilla, Ernesto

    2014-06-01

    Every day new scientific information is appearing that cannot be explained using the classical Newtonian model and is calling for the emergence of a new paradigm that would include the explanation of such phenomena as telepathy, clairvoyance, presentiment, precognition, out of the body experiences, psychic healing, after-death communication, near-death experiences and reincarnation. The materialist paradigm which considers the brain as the sole cause of consciousness and psychic phenomena has been challenged by a new paradigm that seems to demonstrate that there is not a cause-effect relationship between brain activity and psychic phenomena but only a correlation between them, since these phenomena can be experienced without the body and appear to have an extra-cerebral origin (cosmic field, cosmic consciousness?). Of course, the brain is intensely involved in the manifestation of consciousness in our daily life but this is not equivalent to affirm that brain creates consciousness. Recent findings force us to consider a non-physical, spiritual and transpersonal aspect of reality.

  20. Radiation- and pair-loaded shocks

    Science.gov (United States)

    Lyutikov, Maxim

    2018-06-01

    We consider the structure of mildly relativistic shocks in dense media, taking into account the radiation and pair loading, and diffusive radiation energy transfer within the flow. For increasing shock velocity (increasing post-shock temperature), the first important effect is the efficient energy redistribution by radiation within the shock that leads to the appearance of an isothermal jump, whereby the flow reaches the final state through a discontinuous isothermal transition. The isothermal jump, on scales much smaller than the photon diffusion length, consists of a weak shock and a quick relaxation to the isothermal conditions. Highly radiation-dominated shocks do not form isothermal jump. Pair production can mildly increase the overall shock compression ratio to ≈10 (4 for matter-dominated shocks and 7 of the radiation-dominated shocks).

  1. Influence of Housing Wall Compliance on Shock Absorbers in the Context of Vehicle Dynamics

    Science.gov (United States)

    Pulvirenti, G.; Faria, C.

    2017-10-01

    Shock absorbers play a key role in vehicle dynamics. Researchers have spent significant effort in order to understand phenomena associated with this component, but there are still several issues to address, in part because new technology development and design trends continually lead to new challenges, among which weight reduction is crucial. For shock absorbers, weight reduction is related to the use of new materials (e.g. composite) or new design paradigms (e.g. more complex geometry, wall thickness, etc.). All of them are directly linked to wall compliance values higher than the actual ones. The present article proposes a first analysis of the phenomena introduced by a high wall compliance, through a modelling approach and various simulations in order to understand the vehicle behaviour changes. It is shown that high values of wall compliance lead to increased hysteresis in the force-velocity curve. However, comfort, handling and ride performances are not significantly affected by this designing parameter.

  2. Observation of a flare-generated shock wave at 9.7 AU by Pioneer 10

    International Nuclear Information System (INIS)

    Dryer, M.; Shea, M.A.; Smart, D.F.; Collard, H.R.; Mihalov, J.D.; Wolfe, J.H.; Warwick, J.W.

    1978-01-01

    The period March 15 to May 15, 1976, was declared in advance to be the internationally recognized Study of Traveling Interplanetary Phenomena Interval II. A variety of ground- and space-based equipment was requested to make coordinated studies during this part of the minimum of solar cycle 20. Following an absence of solar activity for a long period, several type II radio bursts on March 20, 1976, produced by two solar flares behind the east limb heralded a series of solar interplanetary, and terrestrial events. These solar radio astronomical observations were followed by non-Io-associated radio emission from Jupiter and solar wind plasma detection at Pioneer 10 at 9.7 AU of an apparent shock wave on March 30 and April 9, 1976, respectively. In view of the fact that the solar flares on March 20 were essentially at central meridian with respect to Jupiter and Pioneer 10 and also that the sun was extremely inactive prior to that date we consider the circumstantial evidence that at least one solar-flare-generated shock wave propagated to the position of Pioneer 10. The average velocities of this shock wave, together with the inferred type II velocity, support previous observations and theory concerning the rapid deceleration and survival of interplanetary shock waves to distances at least as large as approx.10 AU. It is therefore believed that dissipation (other than that within shocks themselves) plays an insignificant role in shock wave dynamics within the solar wind

  3. Solar radio bursts of spectral type II, coronal shocks, and optical coronal transients

    Science.gov (United States)

    Maxwell, A.; Dryer, M.

    1981-01-01

    An examination is presented of the association of solar radio bursts of spectral type II and coronal shocks with solar flare ejecta observed in H-alpha, the green coronal line, and white-light coronagraphs. It is suggested that fast-moving optical coronal transients should for the most part be identified with piston-type phenomena well behind the outward-traveling shock waves that generate type II radio bursts. A general model is presented which relates type II radio bursts and coronal shocks to optically observed ejecta and consists of three main velocity regimes: (1) a quasi-hemispherical shock wave moving outward from the flare at speeds of 1000-2000 km/sec and Alfven Mach number of about 1.5; (2) the velocity of the piston driving the shock, on the order of 0.8 that of the shock; and (3) the regime of the slower-moving H-alpha ejecta, with velocities of 300-500 km/sec.

  4. Study Of Severe Accident Phenomena In Nuclear Power Plant

    International Nuclear Information System (INIS)

    Sugiyanto; Antariksawan; Anhar, R.; Arifal

    2001-01-01

    Several phenomena that occurred in the light water reactor type of nuclear power plant during severe accident were studied. The study was carried out based on the results of severe accident researches in various countries. In general, severe accident phenomena can be classified into in-vessel phenomena, retention in the reactor coolant system, and ex-vessel phenomena. In-vessel retention has been recommended as a severe accident management strategy

  5. Prediction of massive bleeding. Shock index and modified shock index.

    Science.gov (United States)

    Terceros-Almanza, L J; García-Fuentes, C; Bermejo-Aznárez, S; Prieto-Del Portillo, I J; Mudarra-Reche, C; Sáez-de la Fuente, I; Chico-Fernández, M

    2017-12-01

    To determine the predictive value of the Shock Index and Modified Shock Index in patients with massive bleeding due to severe trauma. Retrospective cohort. Severe trauma patient's initial attention at the intensive care unit of a tertiary hospital. Patients older than 14 years that were admitted to the hospital with severe trauma (Injury Severity Score >15) form January 2014 to December 2015. We studied the sensitivity (Se), specificity (Sp), positive and negative predictive value (PV+ and PV-), positive and negative likelihood ratio (LR+ and LR-), ROC curves (Receiver Operating Characteristics) and the area under the same (AUROC) for prediction of massive hemorrhage. 287 patients were included, 76.31% (219) were male, mean age was 43,36 (±17.71) years and ISS was 26 (interquartile range [IQR]: 21-34). The overall frequency of massive bleeding was 8.71% (25). For Shock Index: AUROC was 0.89 (95% confidence intervals [CI] 0.84 to 0.94), with an optimal cutoff at 1.11, Se was 91.3% (95% CI: 73.2 to 97.58) and Sp was 79.69% (95% CI: 74.34 to 84.16). For the Modified Shock Index: AUROC was 0.90 (95% CI: 0.86 to 0.95), with an optimal cutoff at 1.46, Se was 95.65% (95% CI: 79.01 to 99.23) and Sp was 75.78% (95% CI: 70.18 to 80.62). Shock Index and Modified Shock Index are good predictors of massive bleeding and could be easily incorporated to the initial workup of patients with severe trauma. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  6. Towards an understanding of resilience: responding to health systems shocks.

    Science.gov (United States)

    Hanefeld, Johanna; Mayhew, Susannah; Legido-Quigley, Helena; Martineau, Frederick; Karanikolos, Marina; Blanchet, Karl; Liverani, Marco; Yei Mokuwa, Esther; McKay, Gillian; Balabanova, Dina

    2018-04-01

    The recent outbreak of Ebola Virus Disease (EVD) in West Africa has drawn attention to the role and responsiveness of health systems in the face of shock. It brought into sharp focus the idea that health systems need not only to be stronger but also more 'resilient'. In this article, we argue that responding to shocks is an important aspect of resilience, examining the health system behaviour in the face of four types of contemporary shocks: the financial crisis in Europe from 2008 onwards; climate change disasters; the EVD outbreak in West Africa 2013-16; and the recent refugee and migration crisis in Europe. Based on this analysis, we identify '3 plus 2' critical dimensions of particular relevance to health systems' ability to adapt and respond to shocks; actions in all of these will determine the extent to which a response is successful. These are three core dimensions corresponding to three health systems functions: 'health information systems' (having the information and the knowledge to make a decision on what needs to be done); 'funding/financing mechanisms' (investing or mobilising resources to fund a response); and 'health workforce' (who should plan and implement it and how). These intersect with two cross-cutting aspects: 'governance', as a fundamental function affecting all other system dimensions; and predominant 'values' shaping the response, and how it is experienced at individual and community levels. Moreover, across the crises examined here, integration within the health system contributed to resilience, as does connecting with local communities, evidenced by successful community responses to Ebola and social movements responding to the financial crisis. In all crises, inequalities grew, yet our evidence also highlights that the impact of shocks is amenable to government action. All these factors are shaped by context. We argue that the '3 plus 2' dimensions can inform pragmatic policies seeking to increase health systems resilience.

  7. Shock diffraction in alumina powder

    International Nuclear Information System (INIS)

    Venz, G.; Killen, P.D.; Page, N.W.

    1996-01-01

    In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

  8. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    International Nuclear Information System (INIS)

    Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C.

    1995-01-01

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation

  9. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C. [Oak Ridge National Lab., TN (United States). Technical Programs and Services; Brock, W.R.; Denton, D.R. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States)

    1995-12-31

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation.

  10. Shock Tube and Ballistic Range Facilities at NASA Ames Research Center

    Science.gov (United States)

    Grinstead, Jay H.; Wilder, Michael C.; Reda, Daniel C.; Cornelison, Charles J.; Cruden, Brett A.; Bogdanoff, David W.

    2010-01-01

    The Electric Arc Shock Tube (EAST) facility and the Hypervelocity Free Flight Aerodynamic Facility (HFFAF) at NASA Ames Research Center are described. These facilities have been in operation since the 1960s and have supported many NASA missions and technology development initiatives. The facilities have world-unique capabilities that enable experimental studies of real-gas aerothermal, gas dynamic, and kinetic phenomena of atmospheric entry.

  11. Climate variability, food production shocks, and violent conflict in Sub-Saharan Africa

    OpenAIRE

    Buhaug, Halvard; Benjaminsen, Tor A; Sjaastad, Espen Olav; Theisen, Ole Magnus

    2015-01-01

    Earlier research that reports a correlational pattern between climate anomalies and violent conflict routinely refers to drought-induced agricultural shocks and adverse economic spillover effects as a key causal mechanism linking the two phenomena. Comparing half a century of statistics on climate variability, food production, and political violence across Sub-Saharan Africa, this study offers the most precise and theoretically consistent empirical assessment to date of the purported indirect...

  12. Energetic ion acceleration at collisionless shocks

    Science.gov (United States)

    Decker, R. B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx. 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity.

  13. Energetic ion acceleration at collisionless shocks

    International Nuclear Information System (INIS)

    Decker, R.B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity

  14. Why the Nature of Oil Shocks Matters

    International Nuclear Information System (INIS)

    Archanskaia, Elizaveta; Hubert, Paul; Creel, Jerome

    2009-03-01

    This article studies the impact of oil shocks on the macro-economy in two ways insofar unexploited in the literature. The analysis is conducted at the global level, and it explicitly accounts for the potentially changing nature of oil shocks. Based on an original world GDP series and a grouping of oil shocks according to their nature, we find that oil supply shocks negatively impact world growth, contrary to oil demand shocks, pro-cyclical in their nature. This result is robust at the national level for the US. Furthermore, endogenous monetary policy is shown to have no counter-cyclical effects in the context of an oil demand shock. (authors)

  15. MHD intermediate shock discontinuities: Pt. 1

    International Nuclear Information System (INIS)

    Kennel, C.F.; Blandford, R.D.; Coppi, P.

    1989-01-01

    Recent numerical investigations have focused attention once more on the role of intermediate shocks in MHD. Four types of intermediate shock are identified using a graphical representation of the MHD Rankine-Hugoniot conditions. This same representation can be used to exhibit the close relationship of intermediate shocks to switch-on shocks and rotational discontinuities. The conditions under which intermediate discontinuities can be found are elucidated. The variations in velocity, pressure, entropy and magnetic-field jumps with upstream parameters in intermediate shocks are exhibited graphically. The evolutionary arguments traditionally advanced against intermediate shocks may fail because the equations of classical MHD are not strictly hyperbolic. (author)

  16. Shock waves in weakly compressed granular media.

    Science.gov (United States)

    van den Wildenberg, Siet; van Loo, Rogier; van Hecke, Martin

    2013-11-22

    We experimentally probe nonlinear wave propagation in weakly compressed granular media and observe a crossover from quasilinear sound waves at low impact to shock waves at high impact. We show that this crossover impact grows with the confining pressure P0, whereas the shock wave speed is independent of P0-two hallmarks of granular shocks predicted recently. The shocks exhibit surprising power law attenuation, which we model with a logarithmic law implying that shock dissipation is weak and qualitatively different from other granular dissipation mechanisms. We show that elastic and potential energy balance in the leading part of the shocks.

  17. Multiscale Modeling of Mesoscale and Interfacial Phenomena

    Science.gov (United States)

    Petsev, Nikolai Dimitrov

    With rapidly emerging technologies that feature interfaces modified at the nanoscale, traditional macroscopic models are pushed to their limits to explain phenomena where molecular processes can play a key role. Often, such problems appear to defy explanation when treated with coarse-grained continuum models alone, yet remain prohibitively expensive from a molecular simulation perspective. A prominent example is surface nanobubbles: nanoscopic gaseous domains typically found on hydrophobic surfaces that have puzzled researchers for over two decades due to their unusually long lifetimes. We show how an entirely macroscopic, non-equilibrium model explains many of their anomalous properties, including their stability and abnormally small gas-side contact angles. From this purely transport perspective, we investigate how factors such as temperature and saturation affect nanobubbles, providing numerous experimentally testable predictions. However, recent work also emphasizes the relevance of molecular-scale phenomena that cannot be described in terms of bulk phases or pristine interfaces. This is true for nanobubbles as well, whose nanoscale heights may require molecular detail to capture the relevant physics, in particular near the bubble three-phase contact line. Therefore, there is a clear need for general ways to link molecular granularity and behavior with large-scale continuum models in the treatment of many interfacial problems. In light of this, we have developed a general set of simulation strategies that couple mesoscale particle-based continuum models to molecular regions simulated through conventional molecular dynamics (MD). In addition, we derived a transport model for binary mixtures that opens the possibility for a wide range of applications in biological and drug delivery problems, and is readily reconciled with our hybrid MD-continuum techniques. Approaches that couple multiple length scales for fluid mixtures are largely absent in the literature, and

  18. Shock, diaschisis and von Monakow

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    2013-07-01

    Full Text Available The concept of shock apparently emerged in the middle of the 18th century (Whyett as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall. The concept was extended (Brown-Séquard and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance". The term "diaschisis" (von Monakow, proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging.

  19. Shock compression of geological materials

    International Nuclear Information System (INIS)

    Kirk, S; Braithwaite, C; Williamson, D; Jardine, A

    2014-01-01

    Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

  20. Shock compression of simulated adobe

    Science.gov (United States)

    Braithwaite, C. H.; Church, P. D.; Gould, P. J.; Stewart, B.; Jardine, A. P.

    2017-01-01

    A series of plate impact experiments were conducted to investigate the shock response of a simulant for adobe, a traditional form of building material widely used around the world. Air dried bricks were sourced from the London brick company, dry machined and impacted at a range of velocities in a single stage gas gun. The shock Hugoniot was determined (Us =2.26up+0.37) as well as release information. The material was found to behave in a manner which was similar to that of loose sand and considerably less stiff than a weak porous sandstone. The effect of any cementing of the grains was examined by shocking powdered samples contained within a cell arrangement.