WorldWideScience

Sample records for atmospheric phenomena

  1. Simulation of nonstationary phenomena in atmospheric-pressure glow discharge

    Science.gov (United States)

    Korolev, Yu. D.; Frants, O. B.; Nekhoroshev, V. O.; Suslov, A. I.; Kas'yanov, V. S.; Shemyakin, I. A.; Bolotov, A. V.

    2016-06-01

    Nonstationary processes in atmospheric-pressure glow discharge manifest themselves in spontaneous transitions from the normal glow discharge into a spark. In the experiments, both so-called completed transitions in which a highly conductive constricted channel arises and incomplete transitions accompanied by the formation of a diffuse channel are observed. A model of the positive column of a discharge in air is elaborated that allows one to interpret specific features of the discharge both in the stationary stage and during its transition into a spark and makes it possible to calculate the characteristic oscillatory current waveforms for completed transitions into a spark and aperiodic ones for incomplete transitions. The calculated parameters of the positive column in the glow discharge mode agree well with experiment. Data on the densities of the most abundant species generated in the discharge (such as atomic oxygen, metastable nitrogen molecules, ozone, nitrogen oxides, and negative oxygen ions) are presented.

  2. Fleets of enduring drones to probe atmospheric phenomena with clouds

    Science.gov (United States)

    Lacroix, Simon; Roberts, Greg; Benard, Emmanuel; Bronz, Murat; Burnet, Frédéric; Bouhoubeiny, Elkhedim; Condomines, Jean-Philippe; Doll, Carsten; Hattenberger, Gautier; Lamraoui, Fayçal; Renzaglia, Alessandro; Reymann, Christophe

    2016-04-01

    A full spatio-temporal four-dimensional characterization of the microphysics and dynamics of cloud formation including the onset of precipitation has never been reached. Such a characterization would yield a better understanding of clouds, e.g. to assess the dominant mixing mechanism and the main source of cloudy updraft dilution. It is the sampling strategy that matters: fully characterizing the evolution over time of the various parameters (P, T, 3D wind, liquid water content, aerosols...) within a cloud volume requires dense spatial sampling for durations of the order of one hour. A fleet of autonomous lightweight UAVs that coordinate themselves in real-time as an intelligent network can fulfill this purpose. The SkyScanner project targets the development of a fleet of autonomous UAVs to adaptively sample cumuli, so as to provide relevant data to address long standing questions in atmospheric science. It mixes basic researches and experimental developments, and gathers scientists in UAV conception, in optimal flight control, in intelligent cooperative behaviors, and of course atmospheric scientists. Two directions of researches are explored: optimal UAV conception and control, and optimal control of a fleet of UAVs. The design of UAVs for atmospheric science involves the satisfaction of trade-offs between payload, endurance, ease of deployment... A rational conception scheme that integrates the constraints to optimize a series of criteria, in particular energy consumption, would yield the definition of efficient UAVs. This requires a fine modeling of each involved sub-system and phenomenon, from the motor/propeller efficiency to the aerodynamics at small scale, including the flight control algorithms. The definition of mission profiles is also essential, considering the aerodynamics of clouds, to allow energy harvesting schemes that exploit thermals or gusts. The conception also integrates specific sensors, in particular wind sensor, for which classic

  3. To investigate or not to investigate? Researchers' views on unexplored atmospheric light phenomena

    Science.gov (United States)

    Caron, Etienne; Faridi, Pouya

    2016-02-01

    For hundreds of years, scientists have been studying light, which is used nowadays to explore the universe and cure diseases. Here, we present the results of a survey indicating a significant support from a subset of the academic community to investigate rare, unusual and unexplained atmospheric light phenomena that have historically been unexplored by scientists — the transient luminous phenomena in the valley of Hessdalen in Norway in particular. We propose that stable, long-term funding, and thorough investigation of poorly understood and/or unexplored luminous phenomena occurring in the low atmosphere could lead to the creation of new inter-disciplinary research programs in multiple universities, and ultimately, to important fundamental discoveries in the field of atmospheric science, photonics and beyond.

  4. Atmospheric Electric Field Measurements at 100 Hz and High Frequency Electric Phenomena

    Science.gov (United States)

    Conceição, Ricardo; Gonçalves da Silva, Hugo; Matthews, James; Bennett, Alec; Chubb, John

    2016-04-01

    Spectral response of Atmospheric Electric Potential Gradient (PG), symmetric to the Atmospheric Electric Field, gives important information about phenomena affecting these measurements with characteristic time-scales that appear in the spectra as specific periodicities. This is the case of urban pollution that has a clear weekly dependence and reveals itself on PG measurements by a ~7 day periodicity (Silva et al., 2014). While long-term time-scales (low frequencies) have been exhaustively explored in literature, short-term time-scales (high frequencies), above 1 Hz, have comparatively received much less attention (Anisimov et al., 1999). This is mainly because of the technical difficulties related with the storage of such a huge amount of data (for 100 Hz sampling two days of data uses a ~1 Gb file) and the response degradation of the field-meters at such frequencies. Nevertheless, important Electric Phenomena occurs for frequencies above 1 Hz that are worth pursuing, e.g. the Schumann Resonances have a signature of worldwide thunderstorm activity at frequencies that go from ~8 up to ~40 Hz. To that end the present work shows preliminary results on PG measurements at 100 Hz that took place on two clear-sky days (17th and 18th June 2015) on the South of Portugal, Évora (38.50° N, 7.91° W). The field-mill used is a JCI 131F installed in the University of Évora campus (at 2 m height) with a few trees and two buildings in its surroundings (~50 m away). This device was developed by John Chubb (Chubb, 2014) and manufactured by Chilworth (UK). It was calibrated in December 2013 and recent work by the author (who is honored in this study for his overwhelming contribution to atmospheric electricity) reveals basically a flat spectral response of the device up to frequencies of 100 Hz (Chubb, 2015). This makes this device suitable for the study of High Frequency Electric Phenomena. Anisimov, S.V., et al. (1999). On the generation and evolution of aeroelectric structures

  5. Atmospheric tides and other relationships: ``Interpreting the Phenomena'' at the time of the Seeberg conference

    Science.gov (United States)

    Kokott, Wolfgang

    research. The Seeberg conference took place in an environment of (prolonged) change from natural history to modern science. In astronomy, the interaction between descriptive, phenomenological methods and quantitative investigations and results was particularly fruitful. Many of the results did emerge slowly: Seemingly atmospheric phenomena, like meteors, did turn out to be of extraterrestrial origin; objects like ejecta from lunar volcanoes eventually became mere figments of imagination. In both cases, unprejudiced observations and their theoretical evaluation were necessary. Chladni's work (1794) on the origin of meteorites did need to be verified by the ``stone shower'' of l'Aigle (1803). And the quest for the missing planet between Mars and Jupiter did not only produce literally many results - it also led to the ``Theoria Motus''.

  6. Long-period fading in atmospherics during severe meteorological activity and associated solar geophysical phenomena at low latitudes

    Directory of Open Access Journals (Sweden)

    A. B. Bhattacharya

    Full Text Available The records of VLF atmospherics over Calcutta and then over Kalyani (West Bengal during the torrential rainfall, caused by violent monsoon and post-monsoon depressions, exhibit distinct long-period fadings both at day and night. Interesting results obtained from an analysis of round-the-clock atmospherics data and associated meteorological parameters are reported in this paper. A possible correlation between the severe meteorological activity with the solar geophysical phenomena was studied. The results are indicative of an interesting sequence of solar-terrestrial events. A tentative conclusion is reached, suggesting an origin of the fading from atmospheric gravity waves generated in the centre of activity of the depressions concerned.

    Key words. Meteorology and atmospheric dynamics · Lightning · Precipitation

  7. Observation of Periodic Multiplication and Chaotic Phenomena in Atmospheric Cold Plasma Jets

    Institute of Scientific and Technical Information of China (English)

    QI Bing; HUANG Jian-Jun; ZHANG Zhe-Huang; WANG De-Zhen

    2008-01-01

    We investigate the temporal evolution of the current pulses from an ac He cold plasma jet at atmospheric pressure and with driving frequency in the range 14.76-15.30 kHz. The driving frequency is used as the plasma system's bifurcation parameter in analogy with the evolution in which the current pulses undergoes multiplication and chaos. Such time-domain nonlinearity is important for controlling instabilities in atmospheric glow discharges.In addition, the observation can provide some data to support the simulation results reported previously [Appl.Phys. Lett. 90 (2007) 071501].

  8. Some Phenomena of the Interaction Between Vegetation and a Atmosphere on Multiple Scales

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This article studies the response of the distribution pattern and the physiological characteristics of the ecosystem to the spontaneous precipitation and the interaction between vegetation and the atmosphere on multiple scales in arid and semi-arid zones, based on measured data of the ecological physiological parameters in the Ordas Plateau of northern China. The results show that the vegetation biomass and the energy use efficiency of photosynthesis are especially sensitive to the annual precipitation; strong and complex interactions exist between the vegetation and the atmosphere on multiple scales leading to supernormal thermal heterogeneity of the underlying surface, the strong vortex movement and turbulence.This study can facilitate understanding of the land surface processes and the influences of global climate change as well as human activities on the human environment in the arid and semi-arid zones. It also aids in improving the parameterization schemes of turbulent fluxes of a heterogeneous underlying surface for land surface processes in climate models.

  9. Atmospheric phenomena deduced from radiosonde and GPS occultation measurements for various application related studies

    Indian Academy of Sciences (India)

    C J Johny; S K Sarkar; D Punyasesudu

    2009-02-01

    The tropopause height and tropopause temperature are sensitive to temperature changes in troposphere and stratosphere. These are the measures of global climatic variability. Atmospheric profiles of temperature, refractivity and water vapour are always needed for communication, navigation and atmospheric modeling studies. The tropopause characteristics over the Indian region have been studied using radio occultation measurements (CHAMP) on the basis of cold point criterion. Tropopause height shows large variation in the latitude range ∼30° –40°N during winter. Tropopause temperature less than −82°C, assumed to facilitate troposphere to stratosphere air transport, is observed at a number of tropical Indian locations and no seasonal pattern is observed in its occurrence. The bias in temperature and refractivity deduced from radiosonde and radio occultation measurements is also presented.

  10. Modeling of asymmetric pulsed phenomena in dielectric-barrier atmospheric-pressure glow discharges

    Energy Technology Data Exchange (ETDEWEB)

    Ha Yan [College of Mathematics and Computer Science, Hebei University, Baoding 071002 (China); Wang Huijuan [School of Mathematics and Physics, North China Electric Power University, Baoding 071003 (China); Wang Xiaofei [College of Physics Science and Technology, Hebei University, Baoding 071002 (China)

    2012-01-15

    Asymmetric current pulses in dielectric-barrier atmospheric-pressure glow discharges are investigated by a self-consistent, one-dimensional fluid model. It is found that the glow mode and Townsend mode can coexist in the asymmetric discharge even though the gas gap is rather large. The reason for this phenomenon is that the residual space charge plays the role of anode and reduces the gap width, resulting in the formation of a Townsend discharge.

  11. Investigation of chemical properties and transport phenomena associated with pollutants in the atmospheric boundary layer

    Science.gov (United States)

    Holmes, Heather A.

    Under the Clean Air Act, the U.S. Environmental Protection Agency is required to determine which air pollutants are harmful to human health, then regulate, monitor and establish criteria levels for these pollutants. To accomplish this and for scientific advancement, integration of knowledge from several disciplines is required including: engineering, atmospheric science, chemistry and public health. Recently, a shift has been made to establish interdisciplinary research groups to better understand the atmospheric processes that govern the transport of pollutants and chemical reactions of species in the atmospheric boundary layer (ABL). The primary reason for interdisciplinary collaboration is the need for atmospheric processes to be treated as a coupled system, and to design experiments that measure meteorological, chemical and physical variables simultaneously so forecasting models can be improved (i.e., meteorological and chemical process models). This dissertation focuses on integrating research disciplines to provide a more complete framework to study pollutants in the ABL. For example, chemical characterization of particulate matter (PM) and the physical processes governing PM distribution and mixing are combined to provide more comprehensive data for source apportionment. Data from three field experiments were utilized to study turbulence, meteorological and chemical parameters in the ABL. Two air quality field studies were conducted on the U.S./Mexico border. The first was located in Yuma, AZ to investigate the spatial and temporal variability of PM in an urban environment and relate chemical properties of ambient aerosols to physical findings. The second border air quality study was conducted in Nogales, Sonora, Mexico to investigate the relationship between indoor and outdoor air quality in order to better correlate cooking fuel types and home activities to elevated indoor PM concentrations. The final study was executed in southern Idaho and focused on

  12. The exo-weather report exploring diverse atmospheric phenomena around the universe

    CERN Document Server

    Stevenson, David S

    2016-01-01

    David Stevenson’s new book links the meteorology of the Earth to that of other planets, stars, and clusters of galaxies, showing the similarities and differences between terrestrial weather and that of weather on other worlds. Because Earth is not unique in having weather, there is much to learn from other planets with atmospheres that show the movement of energy from hotter to colder areas. The weather seen on Earth and other known planetary systems are examined to elaborate the connection between climate and the development of life. The weather on Earth and other Solar System planets is a manifestation of the huge energy budget imparted by our star, the Sun, but weather doesn’t stop at the shores of our Solar System. The author brings together the latest information from satellites and probes, such as Cassini and Hubble, to show its larger place in the astronomical picture. Inferences are drawn about the weather and climate of a large number of other planetary systems that lie far from our own. Addition...

  13. Future monitoring of charged particle energy deposition into the upper atmosphere and comments on possible relationships between atmospheric phenomena and solar and/or geomagnetic activity

    Science.gov (United States)

    Williams, D. J.; Grubb, R. N.; Evans, D. S.; Sauer, H. H.

    1975-01-01

    Monitoring of earth's atmosphere was conducted for several years utilizing the ITOS series of low-altitude, polar-orbiting weather satellites. A space environment monitoring package was included in these satellites to perform measurements of a portion of earth's charged particle environment. The charged particle observations proposed for the low-altitude weather satellite TIROS N, are described which will provide the capability of routine monitoring of the instantaneous total energy deposition into the upper atmosphere by the precipitation of charged particles from higher altitudes. Such observations may be of use in future studies of the relationships between geomagnetic activity and atmospheric weather pattern developments. Estimates are given to assess the potential importance of this type of energy deposition. Discussion and examples are presented illustrating the importance of distinguishing between solar and geomagnetic activity as possible causative sources. Such differentiation is necessary because of the widely different spatial and time scales involved in the atmospheric energy input resulting from these various sources of activity.

  14. 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.

  15. Run-to-run variations, asymmetric pulses, and long time-scale transient phenomena in dielectric-barrier atmospheric pressure glow discharges

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jichul; Raja, Laxminarayan L [Department of Aerospace Engineering and Engineering Mechanics, University of Texas at Austin, Austin, TX 78712 (United States)

    2007-05-21

    The dielectric-barrier (DB) discharge is an important approach to generate uniform non-equilibrium atmospheric-pressure glow discharges. We report run-to-run variations, asymmetric pulse formation and long time-scale transient phenomena in these discharges. For similar DB discharge geometric and operating conditions, we observe significant run-to-run variations as manifested in the different voltage-current waveforms at the start of each new run. These run-to-run variations are also accompanied by asymmetric pulses at the start of each run. The variations are observed to drift to a repeatable true steady-state condition on time scales of order tens of minutes to hours. Asymmetric pulse waveforms drift to a symmetric pulse waveform at the true steady state. We explore reasons for these phenomena and rule out thermal drift during a discharge run and gas-phase impurity buildup as potential causes. The most plausible explanation appears to be variations in the surface characteristics of the DBs between two consecutive runs owing to varying inter-run environmental exposure and the conditioning of the dielectric surface during a run owing to plasma-surface interactions. We speculate that the dielectric surface state affects the secondary electron emission coefficient of the surface which in turn is manifested in the discharge properties. A zero-dimensional model of the discharge is used to explore the effect of secondary electron emission.

  16. Transport Phenomena.

    Science.gov (United States)

    Shah, D. B.

    1984-01-01

    Describes a course designed to achieve a balance between exposing students to (1) advanced topics in transport phenomena, pointing out similarities and differences between three transfer processes and (2) common methods of solving differential equations. (JN)

  17. Transport Phenomena.

    Science.gov (United States)

    McCready, Mark J.; Leighton, David T.

    1987-01-01

    Discusses the problems created in graduate chemical engineering programs when students enter with a wide diversity of understandings of transport phenomena. Describes a two-semester graduate transport course sequence at the University of Notre Dame which focuses on fluid mechanics and heat and mass transfer. (TW)

  18. Bending and turbulent enhancement phenomena of neutral gas flow containing an atmospheric pressure plasma by applying external electric fields measured by schlieren optical method

    Science.gov (United States)

    Yamada, Hiromasa; Yamagishi, Yusuke; Sakakita, Hajime; Tsunoda, Syuichiro; Kasahara, Jiro; Fujiwara, Masanori; Kato, Susumu; Itagaki, Hirotomo; Kim, Jaeho; Kiyama, Satoru; Fujiwara, Yutaka; Ikehara, Yuzuru; Ikehara, Sanae; Nakanishi, Hayao; Shimizu, Nobuyuki

    2016-01-01

    To understand the mechanism of turbulent enhancement phenomena of a neutral gas flow containing plasma ejected from the nozzle of plasma equipment, the schlieren optical method was performed to visualize the neutral gas behavior. It was confirmed that the turbulent starting point became closer to the nozzle exit, as the amplitude of discharge voltage (electric field) increased. To study the effect of electric field on turbulent enhancement, two sets of external electrodes were arranged in parallel, and the gas from the nozzle was allowed to flow between the upper and lower electrodes. It was found that the neutral gas flow was bent, and the bending angle increased as the amplitude of the external electric field increased. The results obtained using a simple model analysis roughly coincide with experimental data. These results indicate that momentum transport from drifted ions induced by the electric field to neutral particles is an important factor that enhances turbulence.

  19. Wave phenomena in sunspots

    Science.gov (United States)

    Löhner-Böttcher, Johannes

    2016-03-01

    Context: The dynamic atmosphere of the Sun exhibits a wealth of magnetohydrodynamic (MHD) waves. In the presence of strong magnetic fields, most spectacular and powerful waves evolve in the sunspot atmosphere. Allover the sunspot area, continuously propagating waves generate strong oscillations in spectral intensity and velocity. The most prominent and fascinating phenomena are the 'umbral flashes' and 'running penumbral waves' as seen in the sunspot chromosphere. Their nature and relation have been under intense discussion in the last decades. Aims: Waves are suggested to propagate upward along the magnetic field lines of sunspots. An observational study is performed to prove or disprove the field-guided nature and coupling of the prevalent umbral and penumbral waves. Comprehensive spectroscopic observations at high resolution shall provide new insights into the wave characteristics and distribution across the sunspot atmosphere. Methods: Two prime sunspot observations were carried out with the Dunn Solar Telescope at the National Solar Observatory in New Mexico and with the Vacuum Tower Telescope at the Teide Observatory on Tenerife. The two-dimensional spectroscopic observations were performed with the interferometric spectrometers IBIS and TESOS. Multiple spectral lines are scanned co-temporally to sample the dynamics at the photospheric and chromospheric layers. The time series (1 - 2.5 h) taken at high spatial and temporal resolution are analyzed according to their evolution in spectral intensities and Doppler velocities. A wavelet analysis was used to obtain the wave power and dominating wave periods. A reconstruction of the magnetic field inclination based on sunspot oscillations was developed. Results and conclusions: Sunspot oscillations occur continuously in spectral intensity and velocity. The obtained wave characteristics of umbral flashes and running penumbral waves strongly support the scenario of slow-mode magnetoacoustic wave propagation along the

  20. Science and Paranormal Phenomena

    CERN Document Server

    Noyes, H P

    1999-01-01

    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 {\\it defined} as contradicting physics.

  1. 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.

  2. 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

  3. 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

  4. 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).

  5. 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

  6. 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...

  7. Fundamentals of Fire Phenomena

    DEFF Research Database (Denmark)

    Quintiere, James

    discipline. It covers thermo chemistry including mixtures and chemical reactions; Introduces combustion to the fire protection student; Discusses premixed flames and spontaneous ignition; Presents conservation laws for control volumes, including the effects of fire; Describes the theoretical bases...... 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...... for empirical aspects of the subject of fire; Analyses ignition of liquids and the importance of evaporation including heat and mass transfer; Features the stages of fire in compartments, and the role of scale modelling in fire. The book is written by Prof. James G. Quintiere from University of Maryland...

  8. Membrane Transport Phenomena (MTP)

    Science.gov (United States)

    Mason, Larry W.

    1997-01-01

    The third semi-annual period of the MTP project has been involved with performing experiments using the Membrane Transport Apparatus (MTA), development of analysis techniques for the experiment results, analytical modeling of the osmotic transport phenomena, and completion of a DC-9 microgravity flight to test candidate fluid cell geometries. Preparations were also made for the MTP Science Concept Review (SCR), held on 13 June 1997 at Lockheed Martin Astronautics in Denver. These activities are detailed in the report.

  9. 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

  10. Paramutation phenomena in plants.

    Science.gov (United States)

    Pilu, Roberto

    2015-08-01

    Paramutation is a particular epigenetic phenomenon discovered in Zea mays by Alexander Brink in the 1950s, and then also found in other plants and animals. Brink coined the term paramutation (from the Greek syllable "para" meaning beside, near, beyond, aside) in 1958, with the aim to differentiate paramutation from mutation. The peculiarity of paramutation with respect to other gene silencing phenomena consists in the ability of the silenced allele (named paramutagenic) to silence the other allele (paramutable) present in trans. The newly silenced (paramutated) allele remains stable in the next generations even after segregation from the paramutagenic allele and acquires paramutagenic ability itself. The inheritance behaviour of these epialleles permits a fast diffusion of a particular gene expression level/phenotype in a population even in the absence of other evolutionary influences, thus breaking the Hardy-Weinberg law. As with other gene silencing phenomena such as quelling in the fungus Neurospora crassa, transvection in Drosophila, co-suppression and virus-induced gene silencing (VIGS) described in transgenic plants and RNA interference (RNAi) in the nematode Caenorhabditis elegans, paramutation occurs without changes in the DNA sequence. So far the molecular basis of paramutation remains not fully understood, although many studies point to the involvement of RNA causing changes in DNA methylation and chromatin structure of the silenced genes. In this review I summarize all paramutation phenomena described in plants, focusing on the similarities and differences between them.

  11. 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

  12. 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).

  13. Birefringence phenomena revisited

    CERN Document Server

    Pereira, Dante D; Gonçalves, Bruno

    2016-01-01

    The propagation of electromagnetic waves is investigated in the context of the isotropic and nonlinear dielectric media at rest in the eikonal limit of the geometrical optics. Taking into account the functional dependence $\\varepsilon=\\varepsilon(E,B)$ and $\\mu=\\mu(E,B)$ for the dielectric coefficients, a set of phenomena related to the birefringence of the electromagnetic waves induced by external fields are derived and discussed. Our results contemplate the known cases already reported in the literature: Kerr, Cotton-Mouton, Jones and magnetoelectric effects. Moreover, new effects are presented here as well as the perspectives of its experimental confirmations.

  14. 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

  15. Solid state phenomena

    CERN Document Server

    Lawrance, R

    1972-01-01

    Solid State Phenomena explores the fundamentals of the structure and their influence on the properties of solids. This book is composed of five chapters that focus on the electrical and thermal conductivities of crystalline solids. Chapter 1 describes the nature of solids, particularly metals and crystalline materials. This chapter also presents a model to evaluate crystal structure, the forces between atom pairs, and the mechanism of plastic and elastic deformation. Chapter 2 demonstrates random vibrations of atoms in a solid using a one-dimensional array, while Chapter 3 examines the resista

  16. MULTISCALE PHENOMENA IN MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    A. BISHOP

    2000-09-01

    This project developed and supported a technology base in nonequilibrium phenomena underpinning fundamental issues in condensed matter and materials science, and applied this technology to selected problems. In this way the increasingly sophisticated synthesis and characterization available for classes of complex electronic and structural materials provided a testbed for nonlinear science, while nonlinear and nonequilibrium techniques helped advance our understanding of the scientific principles underlying the control of material microstructure, their evolution, fundamental to macroscopic functionalities. The project focused on overlapping areas of emerging thrusts and programs in the Los Alamos materials community for which nonlinear and nonequilibrium approaches will have decisive roles and where productive teamwork among elements of modeling, simulations, synthesis, characterization and applications could be anticipated--particularly multiscale and nonequilibrium phenomena, and complex matter in and between fields of soft, hard and biomimetic materials. Principal topics were: (i) Complex organic and inorganic electronic materials, including hard, soft and biomimetic materials, self-assembly processes and photophysics; (ii) Microstructure and evolution in multiscale and hierarchical materials, including dynamic fracture and friction, dislocation and large-scale deformation, metastability, and inhomogeneity; and (iii) Equilibrium and nonequilibrium phases and phase transformations, emphasizing competing interactions, frustration, landscapes, glassy and stochastic dynamics, and energy focusing.

  17. 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...

  18. Transient Lunar Phenomena: Regularity and Reality

    CERN Document Server

    Crotts, Arlin P S

    2007-01-01

    Transient lunar phenomena (TLPs) have been reported for centuries, but their nature is largely unsettled. A review of TLP reports shows regularities in the observations; a key question is whether this structure is imposed by human observer effects, terrestrial atmospheric effects or processes tied to the lunar surface. I interrogate an extensive TLP catalog to determine if human factors determine the distribution of TLP reports. I divide the sample according to variables which should produce varying results if determining factors involve humans e.g., historical epoch or geographical location of the observer, not reflecting phenomena tied to the lunar surface. Regardless of how we split the ample, the results are similar: ~50% of the reports involve crater Aristarchus nd vicinity, ~16% from Plato, ~6% from other recent, major impacts, plus a few at Grimaldi. Mare Crisium produces a robust signal for three of five averages of up to 7% of the reports (however, Crisium is an extended feature). The consistency in ...

  19. Anomalous radon emanation linked to preseismic electromagnetic phenomena

    Directory of Open Access Journals (Sweden)

    Y. Omori

    2007-10-01

    Full Text Available Anomalous emanation of radon (222Rn was observed preceding large earthquakes and is considered to be linked to preseismic electromagnetic phenomena (e.g. great changes of atmospheric electric field and ionospheric disturbances. Here we analyze atmospheric radon concentration and estimate changes of electrical conditions in atmosphere due to preseismic radon anomaly. The increase of radon emanation obeys crustal damage evolution, following a power-law of time-to-earthquake. Moreover, the radon emanation decreases the atmospheric electric field by 40%, besides influencing the maximum strength of atmospheric electric field by 104–105 V/m enough to trigger ionospheric disturbances. These changes are within the ranges observed or explaining electromagnetic phenomena associated with large earthquakes.

  20. Atmospheric Photochemistry

    Science.gov (United States)

    Massey, Harrie; Potter, A. E.

    1961-01-01

    The upper atmosphere offers a vast photochemical laboratory free from solid surfaces, so all reactions take place in the gaseous phase. At 30 km altitude the pressure has fallen to about one-hundredth of that at ground level, and we shall, rather arbitrarily, regard the upper atmosphere as beginning at that height. By a little less than 100 km the pressure has fallen to 10(exp -3) mm Hg and is decreasing by a power of ten for every 15 km increase in altitude. Essentially we are concerned then with the photochemistry of a nitrogen-oxygen mixture under low-pressure conditions in which photo-ionization, as well as photodissociation, plays an important part. Account must also be taken of the presence of rare constituents, such as water vapour and its decomposition products, including particularly hydroxyl, oxides of carbon, methane and, strangely enough, sodium, lithium and calcium. Many curious and unfamiliar reactions occur in the upper atmosphere. Some of them are luminescent, causing the atmosphere to emit a dim light called the airglow. Others, between gaseous ions and neutral molecules, are almost a complete mystery at this time. Similar interesting phenomena must occur in other planetary atmospheres, and they might be predicted if sufficient chemical information were available.

  1. Heavenly Bodies and Phenomena in Petroglyphs

    Science.gov (United States)

    Tokhatyan, Karen

    2016-12-01

    In Armenian culture are amply reflected realities connected with Universe. Their figurative expressions are also petroglyphs in which there are representations of solar signs, swastika, Moon crescend, planets, stars, star groups, constellations, Milky Way, Earth. Among heavenly and atmospheric phenomena are: eclipce, meteor, comet, ligthning, cloud, rain and rainbow. There are many products of scientific thinking: stellar maps, calendars, compasses, astronomical records, Zodiac signs and ideograms. Thousands of the Armenian petroglyphs that were created millennia ago by an indigenous ethnos – Armenians, point to the significant place of celestial bodies and luminaries, especially the Sun, stars, and stellar constellations in our ancestors' cosmological perceptions.

  2. 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

  3. Autoregressive description of biological phenomena

    CERN Document Server

    Morariu, Vasile V; Pop, Alexadru; Soltuz, Stefan M; Buimaga-Iarinca, Luiza; Zainea, Oana

    2008-01-01

    Many natural phenomena can be described by power-laws. A closer look at various experimental data reveals more or less significant deviations from a 1/f spectrum. We exemplify such cases with phenomena offered by molecular biology, cell biophysics, and cognitive psychology. Some of these cases can be described by first order autoregressive (AR) models or by higher order AR models which are short range correlation models. The calculations are checked against astrophysical data which were fitted to a an AR model by a different method. We found that our fitting method of the data give similar results for the astrhophysical data and therefore applied the method for examples mentioned above. Our results show that such phenomena can be described by first or higher order of AR models. Therefore such examples are described by short range correlation properties while they can be easily confounded with long range correlation phenomena.

  4. Mathematical Model for Hit Phenomena

    CERN Document Server

    Ishii, Akira; Hayashi, Takefumi; Matsuda, Naoya; Nakagawa, Takeshi; Arakaki, Hisashi; Yoshida, Narihiko

    2010-01-01

    The mathematical model for hit phenomena in entertainments is presented as a nonlinear, dynamical and non-equilibrium phenomena. The purchase intention for each person is introduced and direct and indirect communications are expressed as two-body and three-body interaction in our model. The mathematical model is expressed as coupled nonlinear differential equations. The important factor in the model is the decay time of rumor for the hit. The calculated results agree very well with revenues of recent 25 movies.

  5. Global atmospheric changes.

    OpenAIRE

    Piver, W T

    1991-01-01

    Increasing concentrations of CO2 and other greenhouse gases in the atmosphere can be directly related to global warming. In terms of human health, because a major cause of increasing atmospheric concentrations of CO2 is the increased combustion of fossil fuels, global warming also may result in increases in air pollutants, acid deposition, and exposure to ultraviolet (UV) radiation. To understand better the impacts of global warming phenomena on human health, this review emphasizes the proces...

  6. 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.

  7. Transport Phenomena and Materials Processing

    Science.gov (United States)

    Kou, Sindo

    1996-10-01

    An extremely useful guide to the theory and applications of transport phenomena in materials processing This book defines the unique role that transport phenomena play in materials processing and offers a graphic, comprehensive treatment unlike any other book on the subject. The two parts of the text are, in fact, two useful books. Part I is a very readable introduction to fluid flow, heat transfer, and mass transfer for materials engineers and anyone not yet thoroughly familiar with the subject. It includes governing equations and boundary conditions particularly useful for studying materials processing. For mechanical and chemical engineers, and anyone already familiar with transport phenomena, Part II covers the many specific applications to materials processing, including a brief description of various materials processing technologies. Readable and unencumbered by mathematical manipulations (most of which are allocated to the appendixes), this book is also a useful text for upper-level undergraduate and graduate-level courses in materials, mechanical, and chemical engineering. It includes hundreds of photographs of materials processing in action, single and composite figures of computer simulation, handy charts for problem solving, and more. Transport Phenomena and Materials Processing: * Describes eight key materials processing technologies, including crystal growth, casting, welding, powder and fiber processing, bulk and surface heat treating, and semiconductor device fabrication * Covers the latest advances in the field, including recent results of computer simulation and flow visualization * Presents special boundary conditions for transport phenomena in materials processing * Includes charts that summarize commonly encountered boundary conditions and step-by-step procedures for problem solving * Offers a unique derivation of governing equations that leads to both overall and differential balance equations * Provides a list of publicly available computer

  8. Undergraduates' understanding of cardiovascular phenomena.

    Science.gov (United States)

    Michael, Joel A; Wenderoth, Mary Pat; Modell, Harold I; Cliff, William; Horwitz, Barbara; McHale, Philip; Richardson, Daniel; Silverthorn, Dee; Williams, Stephen; Whitescarver, Shirley

    2002-12-01

    Undergraduates students in 12 courses at 8 different institutions were surveyed to determine the prevalence of 13 different misconceptions (conceptual difficulties) about cardiovascular function. The prevalence of these misconceptions ranged from 20 to 81% and, for each misconception, was consistent across the different student populations. We also obtained explanations for the students' answers either as free responses or with follow-up multiple-choice questions. These results suggest that students have a number of underlying conceptual difficulties about cardiovascular phenomena. One possible source of some misconceptions is the students' inability to apply simple general models to specific cardiovascular phenomena. Some implications of these results for teachers of physiology are discussed.

  9. Complex Phenomena in Nanoscale Systems

    CERN Document Server

    Casati, Giulio

    2009-01-01

    Nanoscale physics has become one of the rapidly developing areas of contemporary physics because of its direct relevance to newly emerging area, nanotechnologies. Nanoscale devices and quantum functional materials are usually constructed based on the results of fundamental studies on nanoscale physics. Therefore studying physical phenomena in nanosized systems is of importance for progressive development of nanotechnologies. In this context study of complex phenomena in such systems and using them for controlling purposes is of great practical importance. Namely, such studies are brought together in this book, which contains 27 papers on various aspects of nanoscale physics and nonlinear dynamics.

  10. 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

  11. Analysing transfer phenomena in osmotic evaporation

    Directory of Open Access Journals (Sweden)

    Freddy Forero Longas

    2011-12-01

    Full Text Available Osmotic evaporation is a modification of traditional processes using membranes; by means of a vapour pressure differential, produced by a highly concentrated extraction solution, water is transferred through a hydrophobic membrane as vapour. This technique has many advantages over traditional processes, allowing work at atmospheric pressure and low temperatures, this being ideal for heatsensitive products. This paper presents and synthetically analyses the phenomena of heat and mass transfer which occurs in the process and describes the models used for estimating the parameters of interest, such as flow, temperature, heat transfer rate and the relationships that exist amongst them when hollow fibre modules are used, providing a quick reference tool and specific information about this process.

  12. Magnetohydrodynamic (MHD) modelling of solar active phenomena via numerical methods

    Science.gov (United States)

    Wu, S. T.

    1988-01-01

    Numerical ideal MHD models for the study of solar active phenomena are summarized. Particular attention is given to the following physical phenomena: (1) local heating of a coronal loop in an isothermal and stratified atmosphere, and (2) the coronal dynamic responses due to magnetic field movement. The results suggest that local heating of a magnetic loop will lead to the enhancement of the density of the neighboring loops through MHD wave compression. It is noted that field lines can be pinched off and may form a self-contained magnetized plasma blob that may move outward into interplanetary space.

  13. 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.

  14. APRI - Accident Phenomena of Risk Importance. Final Report; APRI - Accident Phenomena of Risk Importance. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Frid, W. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Hammar, L.; Soederman, E. [ES-konsult, Stockholm (Sweden)

    1996-12-01

    The APRI-project started in 1992 with participation of the Swedish Nuclear Power Inspectorate (SKI) and the Swedish utilities. The Finnish utility TVO joined the project in 1993. The aim of the project has been to work with phenomenological questions in severe accidents, concentrating on the risk-dominating issues. The work is reported in separate sub-project reports, the present is the final report of the methodological studies as well as a final report for the total project. The research has led to clarifications of the risk complex, and ameliorated the basis for advanced probabilistic safety analyses, specially for the emission risks (PSA level 2) which are being studied at the Swedish plants. A new method has been tried for analysis of complicated accident courses, giving a possibility for systematic evaluation of the impact of different important phenomena (e.g. melt-through, high pressure melt-through with direct heating of the containment atmosphere, steam explosions). In this method, the phenomena are looked upon as top events of a `phenomena-tree`, illustrating how various conditions must be met before the top-event can happen. This method has been useful, in particular for applying `expert estimates`. 47 refs.

  15. Molecular model for chirality phenomena.

    Science.gov (United States)

    Latinwo, Folarin; Stillinger, Frank H; Debenedetti, Pablo G

    2016-10-21

    Chirality is a hallmark feature for molecular recognition in biology and chemical physics. We present a three-dimensional continuum model for studying chirality phenomena in condensed phases using molecular simulations. Our model system is based upon a simple four-site molecule and incorporates non-trivial kinetic behavior, including the ability to switch chirality or racemize, as well as thermodynamics arising from an energetic preference for specific chiral interactions. In particular, we introduce a chiral renormalization parameter that can locally favor either homochiral or heterochiral configurations. Using this model, we explore a range of chirality-specific phenomena, including the kinetics of chiral inversion, the mechanism of spontaneous chiral symmetry breaking in the liquid, chirally driven liquid-liquid phase separation, and chiral crystal structures.

  16. Thermodynamic constraints on fluctuation phenomena

    Science.gov (United States)

    Maroney, O. J. E.

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  17. 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...

  18. The phenomena of social reality

    OpenAIRE

    Tina Kumelj; Barbara Turk

    2000-01-01

    Social reality originates from social interaction in a social group. It is consolidated with social consensus. It is transcendent and relatively stable. Social reality is maintained in relatively isolated, balanced social environment. Majority of members in a social group spontaneously reacts to deviations. These are characteristics which many authors contribute to social reality. If social reality is to be understood as a collection of social-psychological phenomena, of which the important f...

  19. New phenomena searches at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Soha, Aron; /UC, Davis

    2006-04-01

    The authors report on recent results from the Collider Detector at Fermilab (CDF) experiment, which is accumulating data from proton-antiproton collisions with {radical}s = 1.96 TeV at Run II of the Fermilab Tevatron. The new phenomena being explored include Higgs, Supersymmetry, and large extra dimensions. They also present the latest results of searches for heavy objects, which would indicate physics beyond the Standard Model.

  20. 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

  1. Meteorological phenomena in Western classical orchestral music

    Science.gov (United States)

    Williams, P. D.; Aplin, K. L.

    2012-12-01

    The creative output of composers, writers, and artists is often influenced by their surroundings. To give a literary example, it has been claimed recently that some of the characters in Oliver Twist and A Christmas Carol were based on real-life people who lived near Charles Dickens in London. Of course, an important part of what we see and hear is not only the people with whom we interact, but also our geophysical surroundings. Of all the geophysical phenomena to influence us, the weather is arguably the most significant, because we are exposed to it directly and daily. The weather was a great source of inspiration for Monet, Constable, and Turner, who are known for their scientifically accurate paintings of the skies. But to what extent does weather inspire composers? The authors of this presentation, who are atmospheric scientists by day but amateur classical musicians by night, have been contemplating this question. We have built a systematic musical database, which has allowed us to catalogue and analyze the frequencies with which weather is depicted in a sample of classical orchestral music. The depictions vary from explicit mimicry using traditional and specialized orchestral instruments, through to subtle suggestions. We have found that composers are generally influenced by their own environment in the type of weather they choose to represent. As befits the national stereotype, British composers seem disproportionately keen to depict the UK's variable weather patterns and stormy coastline. Reference: Aplin KL and Williams PD (2011) Meteorological phenomena in Western classical orchestral music. Weather, 66(11), pp 300-306. doi:10.1002/wea.765

  2. APRI-6. Accident Phenomena of Risk Importance

    Energy Technology Data Exchange (ETDEWEB)

    Garis, Ninos; Ljung, J (eds.) (Swedish Radiation Safety Authority, Stockholm (Sweden)); Agrenius, Lennart (ed.) (Agrenius Ingenjoersbyraa AB, Stockholm (Sweden))

    2009-06-15

    Since the early 1980s, nuclear power utilities in Sweden and the Swedish Radiation Safety Authority (SSM) collaborate on the research in severe reactor accidents. In the beginning focus was mostly on strengthening protection against environmental impacts after a severe reactor accident, for example by develop systems for the filtered relief of the reactor containment. Since the early 90s, this focus has shifted to the phenomenological issues of risk-dominant significance. During the years 2006-2008, the partnership continued in the research project APRI-6. The aim was to show whether the solutions adopted in the Swedish strategy for incident management provides adequate protection for the environment. This is done by studying important phenomena in the core melt estimating the amount of radioactivity that can be released to the atmosphere in a severe accident. To achieve these objectives the research has included monitoring of international research on severe accidents and evaluation of results and continued support for research of severe accidents at the Royal Inst. of Technology (KTH) and Chalmers University. The follow-up of international research has promoted the exchange of knowledge and experience and has given access to a wealth of information on various phenomena relevant to events in severe accidents. The continued support to KTH has provided increased knowledge about the possibility of cooling the molten core in the reactor tank and the processes associated with coolability in the confinement and about steam explosions. Support for Chalmers has increased knowledge of the accident chemistry, mainly the behavior of iodine and ruthenium in the containment after an accident.

  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. 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

  5. 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

  6. 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

  7. 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

  8. Ultrasound-induced encapsulated microbubble phenomena

    NARCIS (Netherlands)

    Postema, Michiel; Wamel, van Annemieke; Lancée, Charles T.; Jong, de Nico

    2004-01-01

    When encapsulated microbubbles are subjected to high-amplitude ultrasound, the following phenomena have been reported: oscillation, translation, coalescence, fragmentation, sonic cracking and jetting. In this paper, we explain these phenomena, based on theories that were validated for relatively big

  9. Functional theories of thermoelectric phenomena

    Science.gov (United States)

    Eich, F. G.; Di Ventra, M.; Vignale, G.

    2017-02-01

    We review the progress that has been recently made in the application of time-dependent density functional theory to thermoelectric phenomena. As the field is very young, we emphasize open problems and fundamental issues. We begin by introducing the formal structure of thermal density functional theory, a density functional theory with two basic variables—the density and the energy density—and two conjugate fields—the ordinary scalar potential and Luttinger’s thermomechanical potential. The static version of this theory is contrasted with the familiar finite-temperature density functional theory, in which only the density is a variable. We then proceed to constructing the full time-dependent non equilibrium theory, including the practically important Kohn-Sham equations that go with it. The theory is shown to recover standard results of the Landauer theory for thermal transport in the steady state, while showing greater flexibility by allowing a description of fast thermal response, temperature oscillations and related phenomena. Several results are presented here for the first time, i.e. the proof of invertibility of the thermal response function in the linear regime, the full expression of the thermal currents in the presence of Luttinger’s thermomechanical potential, an explicit prescription for the evaluation of the Kohn-Sham potentials in the adiabatic local density approximation, a detailed discussion of the leading dissipative corrections to the adiabatic local density approximation and the thermal corrections to the resistivity that follow from it.

  10. Black Hole Critical Phenomena Without Black Holes

    CERN Document Server

    Liebling, S L

    2000-01-01

    Studying the threshold of black hole formation via numerical evolution has led to the discovery of fascinating nonlinear phenomena. Power-law mass scaling, aspects of universality, and self-similarity have now been found for a large variety of models. However, questions remain. Here I briefly review critical phenomena, discuss some recent results, and describe a model which demonstrates similar phenomena without gravity.

  11. Interpolating function and Stokes Phenomena

    CERN Document Server

    Honda, Masazumi

    2015-01-01

    When we have two expansions of physical quantity around two different points in parameter space, we can usually construct a family of functions, which interpolates the both expansions. In this paper we study analytic structures of such interpolating functions and discuss their physical implications. We propose that the analytic structures of the interpolating functions provide information on analytic property and Stokes phenomena of the physical quantity, which we approximate by the interpolating functions. We explicitly check our proposal for partition functions of zero-dimensional $\\varphi^4$ theory and Sine-Gordon model. In the zero dimensional Sine-Gordon model, we compare our result with a recent result from resurgence analysis. We also comment on construction of interpolating function in Borel plane.

  12. 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.

  13. Induced-charge Electrokinetic Phenomena

    CERN Document Server

    Bazant, M Z; Bazant, Martin Z.; Squires, Todd M.

    2003-01-01

    Motivated by the recent discovery of AC electro-osmosis near micro-electrodes, we predict a broad class of nonlinear electrokinetic phenomena involving induced interfacial charge. By considering various polarizable objects (metals or dielectrics) in DC and AC applied fields, we develop a simple physical picture of `induced-charge electro-osmosis' (ICEO), the fluid slip at a surface due to an electric field acting on the diffuse charge it induces. We also discuss `induced-charge electrophoresis' (ICEP), the analogous motion of a freely-suspended polarizable particle. Both differ significantly from their classical linear counterparts. We present a mathematical theory of ICEO flows in the weakly nonlinear limit of thin double layers. As an example, we calculate the time-dependent ICEO slip around a metallic sphere with a thin dielectric coating in a suddenly-applied DC field. We briefly discuss possible applications of ICEO to microfluidics and of ICEP to colloidal manipulation.

  14. Emergent Phenomena at Oxide Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, H.Y.

    2012-02-16

    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 {yields} -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 {yields} -t. In quantum mechanics, the time-evolution of the wave-function {Psi} is given by the phase factor e{sup -iEt/{h_bar}} 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

  15. Interference Phenomena in Quantum Information

    CERN Document Server

    Stefanak, Martin

    2010-01-01

    One of the key features of quantum mechanics is the interference of probability amplitudes. The reason for the appearance of interference is mathematically very simple. It is the linear structure of the Hilbert space which is used for the description of quantum systems. In terms of physics we usually talk about the superposition principle valid for individual and composed quantum objects. So, while the source of interference is understandable it leads in fact to many counter-intuitive physical phenomena which puzzle physicists for almost hundred years. The present thesis studies interference in two seemingly disjoint fields of physics. However, both have strong links to quantum information processing and hence are related. In the first part we study the intriguing properties of quantum walks. In the second part we analyze a sophisticated application of wave packet dynamics in atoms and molecules for factorization of integers. The main body of the thesis is based on the original contributions listed separately...

  16. Superfluid analogies of cosmological phenomena

    CERN Document Server

    Volovik, G E

    2001-01-01

    Superfluid 3He-A gives example of how chirality, Weyl fermions, gauge fields and gravity appear in low emergy corner together with corresponding symmetries, including Lorentz symmetry and local SU(N). This supports idea that quantum field theory (Standard Model or GUT) is effective theory describing low-energy phenomena. * Momentum space topology of fermionic vacuum provides topological stability of universality class of systems, where above properties appear. * BCS scheme for 3He-A incorporates both ``relativistic'' infrared regime and ultraviolet ``transplanckian'' range: subtle issues of cut-off in quantum field theory and anomalies can be resolved on physical grounds. This allows to separate ``renormalizable'' terms in action, treated by effective theory, from those obtained only in ``transPlanckian'' physics. * Energy density of superfluid vacuum within effective theory is ~ E_{Planck}^4. Stability analysis of ground state beyond effective theory leads to exact nullification of vacuum energy: equilibrium...

  17. Autistic phenomena in neurotic patients.

    Science.gov (United States)

    Klien, S

    1980-01-01

    I have described a group of patients who are seemingly successful in their professional and social lives, and who seek analysis ostensibly for professional reasons or for minor difficulties in their relationship. However, sooner or later they reveal phenomena which are strikingly similar to those observed in so-called autistic children. These autistic phenomena are characterized by an almost impenetrable encapsulation of part of the personality, mute and implacable resistance to change, and a lack of real emotional contact either with themselves or the analyst. Progress of the analysis reveals an underlying intense fear of pain, and of death, disintegration or breakdown. These anxieties occur as a reaction to real or feared separation, especially when commitment to analysis deepens. In the case I have described in detail the patient used various projective processes to deflect painful emotions either into other people, including the analyst, or into their own bodies. As a consequence the various objects or organs of the body swell up and became suffused with rage as a result of having to contain the unwanted feelings. This process leads in turn to intense persecutory fears and a heightened sensitivity to the analyst's tone of voice and facial expression. It would seem that the initial hypersensitivity of part of the personality is such as to lead it to anticipate danger to such an extent that it expels feelings even before they reach awareness. The sooner the analyst realizes the existence of this hidden part of the patient the less the danger of the analysis becoming an endless and meaningless intellectual dialogue and the greater the possibilities of the patient achieving a relatively stable equilibrium. Although the analyst has to live through a great deal of anxiety with the patient I feel that ultimately the results make it worth while.

  18. 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

  19. Bleed Hole Flow Phenomena Studied

    Science.gov (United States)

    1997-01-01

    Boundary-layer bleed is an invaluable tool for controlling the airflow in supersonic aircraft engine inlets. Incoming air is decelerated to subsonic speeds prior to entering the compressor via a series of oblique shocks. The low momentum flow in the boundary layer interacts with these shocks, growing in thickness and, under some conditions, leading to flow separation. To remedy this, bleed holes are strategically located to remove mass from the boundary layer, reducing its thickness and helping to maintain uniform flow to the compressor. The bleed requirements for any inlet design are unique and must be validated by extensive wind tunnel testing to optimize performance and efficiency. To accelerate this process and reduce cost, researchers at the NASA Lewis Research Center initiated an experimental program to study the flow phenomena associated with bleed holes. Knowledge of these flow properties will be incorporated into computational fluid dynamics (CFD) models that will aid engine inlet designers in optimizing bleed configurations before any hardware is fabricated. This ongoing investigation is currently examining two hole geometries, 90 and 20 (both with 5-mm diameters), and various flow features.

  20. Understanding empathy and related phenomena.

    Science.gov (United States)

    Shamasundar, C

    1999-01-01

    Over a period of time, the author arrived at a few tentative postulates concerning empathy and related processes based on some of his experiences and observations. The central theme of these postulates is, firstly, that interpersonal interaction is an interaction of the personal-space fields. Secondly, empathy, therapeutic benefit, and the professional stress are all related to the same process of interpersonal interaction. This interaction takes place as an enmeshment of personal spaces of the interacting individuals, and involves transfer of a wide range of information in the affective, cognitive, and other areas. This is because the personal spaces have fieldlike qualities analogous to what Kurt Lewin described. Thus, such phenomena as empathy, therapeutic benefit, professional stress are all consequences of the same process. It is possible to substantiate these postulates by diverse evidences in the published literature. The natural consequences of such an interpersonal interaction are empathic understanding, transfer of mood states (like hope, distress or expectancy), affective states (like anxiety, sadness, anger or hostility), ideas, images and even attitudes and values, etc. This phenomenon of transfer can explain such processes as therapeutic benefit in individual and group settings, professional stress, shared delusions, and even experimenter bias. Whether one becomes aware of such transferred information or not depends upon the intent and sensitivity of the participants.

  1. Understanding the physics of changing mass phenomena

    OpenAIRE

    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 jumper. These phenomena are also interesting as topics for challenging student projects, and used as such by Dutch high school students. I will take these phenomena as the context in which I like to...

  2. Black hole critical phenomena without black holes

    Indian Academy of Sciences (India)

    Steven L Liebling

    2000-10-01

    Studying the threshold of black hole formation via numerical evolution has led to the discovery of fascinating nonlinear phenomena. Power-law mass scaling, aspects of universality, and self-similarity have now been found for a large variety of models. However, questions remain. Here I briefly review critical phenomena, discuss some recent results, and describe a model which demonstrates similar phenomena without gravity.

  3. Astronomy and Atmospheric Optics

    Science.gov (United States)

    Cowley, Les; Gaina, Alex

    2011-12-01

    The authors discusse the insuccess of the observation of the Total Eclipse of the Moon from 10 december 2011 in Romania and relate them with meteoconditions. Only a very short part of the last penumbral phase was observed, while the inital part and the totality was not observed due to very dense clouds. The change in color and brightness during this phase was signaled. Meanwhile, there is an area of science where clouds are of great use and interest. This area is Atmospheric optics, while the science which study clouds is meteorology. Clouds in combination with Solar and Moon light could give rise to a variety of strange, rare and unobvious phenomena in the atmosphere (sky), sometimes confused with Unidentified Flying Objects (UFO). The importance of meteorology for astronomy and atmospheric optics is underlined and an invitation to astronomers to use unfavourable days for athmospheric observations was sent. The web address of the site by Les Cowley, designed for atmospheric optics phenomena is contained in the text of the entry.

  4. 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.

  5. Magnetic influence on the unidentified luminous phenomena in Hessdalen, Norway

    Science.gov (United States)

    Gitle Hauge, Bjørn; Kjøniksen, Anna-Lena; Petter Strand, Erling; Zlotnicki, Jaques; Vargemezis, George

    2016-04-01

    Unidentified luminous phenomena have been observed in the low atmosphere over the Hessdalen valley for decades. First scientific investigation was done by E.Strand in 1984, where spiral movements of lights was recorded. The Science Camp program has conducted yearly field investigations since 2002 and has confirmed the existence of this spiral-behavior. (http://sciencecamp.no) Such behavior has also been documented in Alabama, USA. In September 2015 spiral like movement of lights was observed together with the more common spherical lights. This spiral movement indicates the presence of low atmospheric charged matter, moving in a magnetic field. A geological survey in 2014 reviled the presence of strong magnetic anomalies. The valley contains several abandoned copper mines containing Chalcopyrite and Magnetite. The Magnetite was not useful in the copper production, and left in heaps around the valley unused. This may contribute to the magnetic anomalies in the valley.

  6. Synchronization Phenomena and Epoch Filter of Electroencephalogram

    Science.gov (United States)

    Matani, Ayumu

    Nonlinear electrophysiological synchronization phenomena in the brain, such as event-related (de)synchronization, long distance synchronization, and phase-reset, have received much attention in neuroscience over the last decade. These phenomena contain more electrical than physiological keywords and actually require electrical techniques to capture with electroencephalography (EEG). For instance, epoch filters, which have just recently been proposed, allow us to investigate such phenomena. Moreover, epoch filters are still developing and would hopefully generate a new paradigm in neuroscience from an electrical engineering viewpoint. Consequently, electrical engineers could be interested in EEG once again or from now on.

  7. 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....

  8. 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....

  9. 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.

  10. 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

  11. 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

  12. 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...

  13. 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.

  14. Periglacial phenomena affecting nuclear waste disposal

    Directory of Open Access Journals (Sweden)

    Niini, H.

    1997-12-01

    Full Text Available Slow future changes in astronomic phenomena seem to make it likely that Finland nll suffer several cold periods during the next 100,000 years. The paper analyses the characteristics of the periglacial factors that are most likely to influence the long-term safety of high-level radioactive waste disposed of in bedrock. These factors and their influences have been divided into two categories, natural and human. It is concluded that the basically natural phenomena are theoretically better understood than the complicated phenomena caused by man. It is therefore important in future research into periglacial phenomena, as well as of the disposal problem, to emphasize not only the proper applications of the results of natural sciences, but especially the effects and control of mankind's own present and future activities.

  15. Sorption phenomena of PCBs in environment

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorption phenomena of PCBs in the environment are described with different models. The research progress on the sorption mechanisms is also discussed.

  16. CISM Course on Rolling Contact Phenomena

    CERN Document Server

    Kalker, Joost

    2000-01-01

    Preface.- Rolling Contact Phenomena - Linear Elasticity.- Finite Element Methods for Rolling Contact.- Plastic Deformation in Rolling Contact.- Non-Steady State Rolling Contact and Corrugations.- Modelling of Tyre Force and Moment Generation.- Rolling Noise.- Lubrication

  17. 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 prese...... 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....

  18. Staging atmospheres

    DEFF Research Database (Denmark)

    Bille, Mikkel; Bjerregaard, Peter; Sørensen, Tim Flohr

    2015-01-01

    The article introduces the special issue on staging atmospheres by surveying the philosophical, political and anthropological literature on atmosphere, and explores the relationship between atmosphere, material culture, subjectivity and affect. Atmosphere seems to occupy one of the classic...... localities of tensions between matter and the immaterial, the practical and the ideal, and subject and object. In the colloquial language there can, moreover, often seem to be something authentic or genuine about atmosphere, juxtaposing it to staging, which is implied to be something simulated or artificial....... This introduction seeks to outline how a number of scholars have addressed the relationship between staged atmospheres and experience, and thus highlight both the philosophical, social and political aspects of atmospheres...

  19. Active Cyber Defense Dynamics Exhibiting Rich Phenomena

    CERN Document Server

    Zheng, Ren; Xu, Shouhuai

    2016-01-01

    The Internet is a man-made complex system under constant attacks (e.g., Advanced Persistent Threats and malwares). It is therefore important to understand the phenomena that can be induced by the interaction between cyber attacks and cyber defenses. In this paper, we explore the rich phenomena that can be exhibited when the defender employs active defense to combat cyber attacks. To the best of our knowledge, this is the first study that shows that {\\em active cyber defense dynamics} (or more generally, {\\em cybersecurity dynamics}) can exhibit the bifurcation and chaos phenomena. This has profound implications for cyber security measurement and prediction: (i) it is infeasible (or even impossible) to accurately measure and predict cyber security under certain circumstances; (ii) the defender must manipulate the dynamics to avoid such {\\em unmanageable situations} in real-life defense operations.

  20. Stability and Restoration phenomena in Competitive Systems

    CERN Document Server

    Uechi, Lisa

    2012-01-01

    A conservation law and stability, recovering phenomena and characteristic patterns of a nonlinear dynamical system have been studied and applied to biological and ecological systems. In our previous study, we proposed a system of symmetric 2n-dimensional conserved nonlinear differential equations with external perturbations. In this paper, competitive systems described by 2-dimensional nonlinear dynamical (ND) model with external perturbations are applied to population cycles and recovering phenomena of systems from microbes to mammals. The famous 10-year cycle of population density of Canadian lynx and snowshoe hare is numerically analyzed. We find that a nonlinear dynamical system with a conservation law is stable and generates a characteristic rhythm (cycle) of population density, which we call the {\\it standard rhythm} of a nonlinear dynamical system. The stability and restoration phenomena are strongly related to a conservation law and balance of a system. The {\\it standard rhythm} of population density ...

  1. Quantum phenomena in magnetic nano clusters

    Indian Academy of Sciences (India)

    C Raghu; Indranil Rudra; Diptiman Sen; S Ramasesha

    2001-10-01

    One of the fascinating fields of study in magnetism in recent years has been the study of quantum phenomena in nanosystems. While semiconductor structures have provided paradigms of nanosystems from the stand point of electronic phenomena, the synthesis of high nuclearity transition metal complexes have provided examples of nano magnets. The range and diversity of the properties exhibited by these systems rivals its electronic counterparts. Qualitative understanding of these phenomena requires only a knowledge of basic physics, but quantitative study throws up many challenges that are similar to those encountered in the study of correlated electronic systems. In this article, a brief overview of the current trends in this area are highlighted and some of the efforts of our group in developing a quantitative understanding of this field are outlined.

  2. The resonance phenomena and state of health

    Directory of Open Access Journals (Sweden)

    Sikura A.Y.

    2010-06-01

    Full Text Available The question of dependence of the state of health is examined from the resonance phenomena in the liquid environments of organism, roles herein physical loadings. It is rotined that resonance waves can compensate structural violations on a tissue, system levels. The oppressive operating is the same compensated on the organism of man. The physical loading in a complex with other external resonance phenomena causes substantial resonance vibrations in all systems of organism. It is necessary to take into account it on employments on physical education and to use all necessary rehabilitation facilities.

  3. Phenomena at hot-wire electrodes.

    Science.gov (United States)

    Gründler, P

    2000-06-01

    An overview is given describing phenomena at heated microelectrodes where matter and heat energy are simultaneously emitted into the solution. With controlled electric heating, virtual "quiescent" periods as well as ones with constant streaming conditions are found that depend on the heating time. A close look at a permanently heated wire reveals a well defined structure with stationary concentration, temperature and flow rate profiles. The observed phenomena can be utilised for analytical measurements, e.g. with the novel method "Temperature Pulse Voltammetry" (TPV).

  4. Current-driven phenomena in nanoelectronics

    CERN Document Server

    Seideman, Tamar

    2010-01-01

    Consisting of ten chapters written by some of the world's leaders in the field, this book combines experimental, theoretical and numerical studies of current-driven phenomena in the nanoscale. The topics covered range from single-molecule, site-specific nanochemistry induced by a scanning tunneling microscope, through inelastic tunneling spectroscopy and current-induced heating, to current-triggered molecular machines. The various chapters focus on experimental and numerical method development, the description of specific systems, and new ideas and novel phenomena.

  5. 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.

  6. 19th International Conference on Ultrafast Phenomena

    CERN Document Server

    Cundiff, Steven; Vivie-Riedle, Regina; Kuwata-Gonokami, Makoto; DiMauro, Louis

    2015-01-01

    This book 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 19th International Conference on Ultrafast Phenomena and provides an up-to-date view of this important and rapidly advancing field.

  7. Coastal Meteorological Phenomena in CalNex

    Science.gov (United States)

    Angevine, W. M.; Brioude, J.

    2010-12-01

    Coastal meteorology plays an important role in air quality and climate in California. During the 2010 CalNex experiment, several phenomena affected the campaign observations. Among these were coastal eddies and outflow in Santa Monica Bay and the Los Angeles Bight; marine stratus and stratocumulus; and the land-sea breeze cycle on a variety of spatial scales, including transport from the San Francisco Bay Area into the Central Valley. In this presentation, we will describe these phenomena as they were seen in model forecasts and hindcast simulations, and compare those simulations to the relevant meteorological observations.

  8. Modeling of fundamental phenomena in welds

    Energy Technology Data Exchange (ETDEWEB)

    Zacharia, T.; Vitek, J.M. [Oak Ridge National Lab., TN (United States); Goldak, J.A. [Carleton Univ., Ottawa, Ontario (Canada); DebRoy, T.A. [Pennsylvania State Univ., University Park, PA (United States); Rappaz, M. [Ecole Polytechnique Federale de Lausanne (Switzerland); Bhadeshia, H.K.D.H. [Cambridge Univ. (United Kingdom)

    1993-12-31

    Recent advances in the mathematical modeling of fundamental phenomena in welds are summarized. State-of-the-art mathematical models, advances in computational techniques, emerging high-performance computers, and experimental validation techniques have provided significant insight into the fundamental factors that control the development of the weldment. The current status and scientific issues in the areas of heat and fluid flow in welds, heat source metal interaction, solidification microstructure, and phase transformations are assessed. Future research areas of major importance for understanding the fundamental phenomena in weld behavior are identified.

  9. 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...

  10. Charged dust phenomena in the near-Earth space environment

    Science.gov (United States)

    Scales, W. A.; Mahmoudian, A.

    2016-10-01

    Dusty (or complex) plasmas in the Earth’s middle and upper atmosphere ultimately result in exotic phenomena that are currently forefront research issues in the space science community. This paper presents some of the basic criteria and fundamental physical processes associated with the creation, evolution and dynamics of dusty plasmas in the near-Earth space environment. Recent remote sensing techniques to probe naturally created dusty plasma regions are also discussed. These include ground-based experiments employing high-power radio wave interaction. Some characteristics of the dusty plasmas that are actively produced by space-borne aerosol release experiments are discussed. Basic models that may be used to investigate the characteristics of such dusty plasma regions are presented.

  11. Establishment of the new Ecuadorian solar physics phenomena division

    CERN Document Server

    Lopez, Ericson D

    2013-01-01

    Crucial physical phenomena occur in the equatorial atmosphere and ionosphere, which are currently understudied and poorly understood. Then, scientific campaigns for monitoring equatorial region are required, which will provide the data for analyzing and creating adequate models. Ecuador is located in strategic geographical position where these studies can be performed, providing data for the scientific community working for understanding the nature of these physical systems. The Quito Astronomical Observatory of National Polytechnic School is working in this direction, promoting research in Space Sciences for studying the equatorial zone. With the participation and valuable collaboration of international initiatives like AWESOME, MAGDAS, SAVNET and CALLISTO, the Quito Observatory is creating a new space physics division on the basis of the International Space Weather Initiative. In this contribution, the aforementioned initiative is presented inviting leaders from others scientific projects to deploy their in...

  12. Exoplanet Atmospheres

    CERN Document Server

    Seager, S

    2010-01-01

    At the dawn of the first discovery of exoplanets orbiting sun-like stars in the mid-1990s, few believed that observations of exoplanet atmospheres would ever be possible. After the 2002 Hubble Space Telescope detection of a transiting exoplanet atmosphere, many skeptics discounted it as a one-object, one-method success. Nevertheless, the field is now firmly established, with over two dozen exoplanet atmospheres observed today. Hot Jupiters are the type of exoplanet currently most amenable to study. Highlights include: detection of molecular spectral features; observation of day-night temperature gradients; and constraints on vertical atmospheric structure. Atmospheres of giant planets far from their host stars are also being studied with direct imaging. The ultimate exoplanet goal is to answer the enigmatic and ancient question, "Are we alone?" via detection of atmospheric biosignatures. Two exciting prospects are the immediate focus on transiting super Earths orbiting in the habitable zone of M-dwarfs, and u...

  13. Atmospheric Neutrinos

    OpenAIRE

    Takaaki Kajita

    1994-01-01

    Atmospheric neutrinos are produced as decay products in hadronic showers resulting from collisions of cosmic rays with nuclei in the atmosphere. Electron-neutrinos and muon-neutrinos are produced mainly by the decay chain of charged pions to muons to electrons. Atmospheric neutrino experiments observed zenith angle and energy-dependent deficit of muon-neutrino events. It was found that neutrino oscillations between muon-neutrinos and tau-neutrinos explain these data well. This paper discusses...

  14. Articulating Atmospheres

    DEFF Research Database (Denmark)

    Kinch, Sofie

    2011-01-01

    This paper presents an architectural approach to designing computational interfaces by articulating the notion of atmosphere in the field of interaction design. It draws upon the concept of kinesthetic interaction and a philosophical notion on atmosphere emphasizing the importance of bodily...... experience in space, presented as middle ground experience. In the field of HCI, middle ground experiences complete the unarticulated spectrum between designing for foreground of attention or background awareness. When “Articulating Atmospheres through Middle Ground Experiences in Interaction Design...

  15. Atmospheric Neutrinos

    Directory of Open Access Journals (Sweden)

    Takaaki Kajita

    2012-01-01

    Full Text Available Atmospheric neutrinos are produced as decay products in hadronic showers resulting from collisions of cosmic rays with nuclei in the atmosphere. Electron-neutrinos and muon-neutrinos are produced mainly by the decay chain of charged pions to muons to electrons. Atmospheric neutrino experiments observed zenith angle and energy-dependent deficit of muon-neutrino events. It was found that neutrino oscillations between muon-neutrinos and tau-neutrinos explain these data well. This paper discusses atmospheric neutrino experiments and the neutrino oscillation studies with these neutrinos.

  16. Atmospheric electricity

    CERN Document Server

    Chalmers, J Alan

    1957-01-01

    Atmospheric Electricity brings together numerous studies on various aspects of atmospheric electricity. This book is composed of 13 chapters that cover the main problems in the field, including the maintenance of the negative charge on the earth and the origin of the charges in thunderstorms. After a brief overview of the historical developments of atmospheric electricity, this book goes on dealing with the general principles, results, methods, and the MKS system of the field. The succeeding chapters are devoted to some aspects of electricity in the atmosphere, such as the occurrence and d

  17. Transport Phenomena in Textile Finishing Equipment

    NARCIS (Netherlands)

    Groot Wassink, J.

    1985-01-01

    The application of transport phenomena to textile finishing processes is emphasised. By combination of the predominant transfer processes (momentum, mass and heat/mass transfer) and the engineering objective (operation, design and innovation), three cases are selected dealing with (a) momentum trans

  18. 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...

  19. Comparing potato tuberization and sprouting: opposite phenomena

    NARCIS (Netherlands)

    Vreugdenhil, D.

    2004-01-01

    The regulation of tuber formation and tuber sprouting are compared. As a starting point it is hypothesized that these two phenomena are opposite to each other. This idea is tested from three points of view: hormonal regulation, gene expression, and carbohydrate metabolism. It is concluded that there

  20. 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 instanta

  1. 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...

  2. Double Negative Materials (DNM), Phenomena and Applications

    Science.gov (United States)

    2009-07-01

    9 Feynman , R. P., R. B. Leighton, and M. Sands. Quantum physics . Vol. 1 of The Feynman Lectures on Physics (Addison-Wesley, 1964...involved in justifying basic physical questions of causality, validity of the concept of negative index of refraction interpretation of experimental...Materials ......................................... 2-4 3. Basic Physics Phenomena

  3. Transport phenomena in strongly correlated Fermi liquids

    Energy Technology Data Exchange (ETDEWEB)

    Kontani, Hiroshi [Nagoya Univ., Aichi (Japan). Dept. of Physics

    2013-03-01

    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, {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 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.

  4. 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 j

  5. Geophysical phenomena classification by artificial neural networks

    Science.gov (United States)

    Gough, M. P.; Bruckner, J. R.

    1995-01-01

    Space science information systems involve accessing vast data bases. There is a need for an automatic process by which properties of the whole data set can be assimilated and presented to the user. Where data are in the form of spectrograms, phenomena can be detected by pattern recognition techniques. Presented are the first results obtained by applying unsupervised Artificial Neural Networks (ANN's) to the classification of magnetospheric wave spectra. The networks used here were a simple unsupervised Hamming network run on a PC and a more sophisticated CALM network run on a Sparc workstation. The ANN's were compared in their geophysical data recognition performance. CALM networks offer such qualities as fast learning, superiority in generalizing, the ability to continuously adapt to changes in the pattern set, and the possibility to modularize the network to allow the inter-relation between phenomena and data sets. This work is the first step toward an information system interface being developed at Sussex, the Whole Information System Expert (WISE). Phenomena in the data are automatically identified and provided to the user in the form of a data occurrence morphology, the Whole Information System Data Occurrence Morphology (WISDOM), along with relationships to other parameters and phenomena.

  6. Nitrous oxide sedation and sexual phenomena.

    Science.gov (United States)

    Jastak, J T; Malamed, S F

    1980-07-01

    Nine cases of sexual phenomena that occurred with use of nitrous oxide and oxygen sedation are described. Dentists involved routinely used concentrations of nitrous oxide greater than 50% and did not have assistants in the room during dental procedures. Recommendations on the concentrations of nitrous oxide and the presence of an assistant are made.

  7. Observations of Nonlinear Phenomena in Rotordynamics

    Science.gov (United States)

    Ehrich, Fredric F.

    Observations, analysis and understanding of nonlinear rotordynamic phenomena observed in aircraft gas turbine engines and other high-speed rotating machinery over the course of the author's career are described. Included are observations of sum-and-difference frequency response; effects of roller bearing clearance; relaxation oscillations; subharmonic response; chaotic response; and other generic nonlinear responses such as superharmonic and ultra-subharmonic response.

  8. CHOSEN PROBLEMS OF FORECASTING SOCIAL PHENOMENA: FORECASTING, BACKCASTING, AND FORESIGHT

    OpenAIRE

    Donaj, Łukasz

    2012-01-01

    Forecasting social phenomena can in many ways be difficult. The reason is that it is the nature of these phenomena to be closely and multilaterally linked with physical, biological, and other social phenomena. Thus, making judgements about the future course of social phenomena, which, unlike physical phenomena based on “strong” science, are dependent on a large number of factors with varying degrees of stability is a complex task. The aim of the publication is an analysis of selected issues t...

  9. Parity-time symmetric quantum critical phenomena

    CERN Document Server

    Ashida, Yuto; Ueda, Masahito

    2016-01-01

    Symmetry plays a central role in the theory of phase transitions. Parity-time (PT) symmetry is an emergent notion in synthetic nonconservative systems, where the gain-loss balance creates a threshold for spontaneous symmetry breaking across which spectral singularity emerges. Considerable studies on PT symmetry have been conducted in optics and weakly interacting open quantum systems. Here by extending the idea of PT symmetry to strongly correlated many-body systems, we discover unconventional quantum critical phenomena, where spectral singularity and quantum criticality conspire to yield an exotic universality class which has no counterpart in known critical phenomena. Moreover, we find that superfluid correlation is anomalously enhanced owing to winding renormalization group flows in a PT-symmetry-broken quantum critical phase. Our findings can experimentally be tested in ultracold atoms.

  10. Study of non-equilibrium transport phenomena

    Science.gov (United States)

    Sharma, Surendra P.

    1987-01-01

    Nonequilibrium phenomena due to real gas effects are very important features of low density hypersonic flows. The shock shape and emitted nonequilibrium radiation are identified as the bulk flow behavior parameters which are very sensitive to the nonequilibrium phenomena. These parameters can be measured in shock tubes, shock tunnels, and ballistic ranges and used to test the accuracy of computational fluid dynamic (CFD) codes. Since the CDF codes, by necessity, are based on multi-temperature models, it is also desirable to measure various temperatures, most importantly, the vibrational temperature. The CFD codes would require high temperature rate constants, which are not available at present. Experiments conducted at the NASA Electric Arc-driven Shock Tube (EAST) facility reveal that radiation from steel contaminants overwhelm the radiation from the test gas. For the measurement of radiation and the chemical parameters, further investigation and then appropriate modifications of the EAST facility are required.

  11. Transport Phenomena During Equiaxed Solidification of Alloys

    Science.gov (United States)

    Beckermann, C.; deGroh, H. C., III

    1997-01-01

    Recent progress in modeling of transport phenomena during dendritic alloy solidification is reviewed. Starting from the basic theorems of volume averaging, a general multiphase modeling framework is outlined. This framework allows for the incorporation of a variety of microscale phenomena in the macroscopic transport equations. For the case of diffusion dominated solidification, a simplified set of model equations is examined in detail and validated through comparisons with numerous experimental data for both columnar and equiaxed dendritic growth. This provides a critical assessment of the various model assumptions. Models that include melt flow and solid phase transport are also discussed, although their validation is still at an early stage. Several numerical results are presented that illustrate some of the profound effects of convective transport on the final compositional and structural characteristics of a solidified part. Important issues that deserve continuing attention are identified.

  12. 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...

  13. 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...

  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. Oxide interfaces: pathways to novel phenomena

    Directory of Open Access Journals (Sweden)

    Pu Yu

    2012-07-01

    Full Text Available Novel phenomena and functionalities at artificial heterointerfaces have been attracting extensive scientific attention in both materials science and fundamental condensed matter physics. The interplay between degrees of freedom at interfaces of complex oxides could lead to exotic and unexpected states of matter. In this article, using the model system of BiFeO3 and La0.7Sr0.3MnO3, we review recent progress on our understanding of the novel states formed at this heterointerface. Furthermore, we discuss how emergent interfacial phenomena can be employed to influence the bulk properties of these materials. We summarize by highlighting several possible and promising directions for future study.

  16. Probabilistic Dynamic Logic of Phenomena and Cognition

    CERN Document Server

    Vityaev, Evgenii; Perlovsky, Leonid; Smerdov, Stanislav

    2011-01-01

    The purpose of this paper is to develop further the main concepts of Phenomena Dynamic Logic (P-DL) and Cognitive Dynamic Logic (C-DL), presented in the previous paper. The specific character of these logics is in matching vagueness or fuzziness of similarity measures to the uncertainty of models. These logics are based on the following fundamental notions: generality relation, uncertainty relation, simplicity relation, similarity maximization problem with empirical content and enhancement (learning) operator. We develop these notions in terms of logic and probability and developed a Probabilistic Dynamic Logic of Phenomena and Cognition (P-DL-PC) that relates to the scope of probabilistic models of brain. In our research the effectiveness of suggested formalization is demonstrated by approximation of the expert model of breast cancer diagnostic decisions. The P-DL-PC logic was previously successfully applied to solving many practical tasks and also for modelling of some cognitive processes.

  17. Atmospheric materiality

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2016-01-01

    experience and, consequently, to the conceptual and methodological shifts in the production of space, and hence in the way we think about materiality. In this context, architectural space is understood as a contingent construction – a space of engagement that appears to us as a result of continuous...... characteristics of atmosphere as a spatial phenomenon, the aim of this text is to illustrate these associations and draw out design protocols, focusing on ways in which atmosphere can be conditioned architecturally. In other words, the objective is to trace the conceptual contours of ‘atmospheric materiality’....

  18. 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.

  19. Littoral Subsonic Seismoacoustic Phenomena Ultrasonic Modeling

    Science.gov (United States)

    2016-06-07

    Littoral Subsonic Seismoacoustic Phenomena Ultrasonic Modeling Jacques R. Chamuel Sonoquest Advanced Ultrasonics Research P.O. Box 81153 Wellesley... variable water/air content, and benthic shelled animals leading to accurate acoustic modeling of littoral surficial layer and geophysical inversion...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Sonoquest Advanced Ultrasonics Research ,P.O. Box 81153,Wellesley Hills,MA,02481-0001 8

  20. Natural phenomena hazards site characterization criteria

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    The criteria and recommendations in this standard shall apply to site characterization for the purpose of mitigating Natural Phenomena Hazards (wind, floods, landslide, earthquake, volcano, etc.) in all DOE facilities covered by DOE Order 5480.28. Criteria for site characterization not related to NPH are not included unless necessary for clarification. General and detailed site characterization requirements are provided in areas of meteorology, hydrology, geology, seismology, and geotechnical studies.

  1. 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....

  2. 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.

  3. 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.

  4. Thermal transport phenomena in nanoparticle suspensions

    Science.gov (United States)

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

    2016-12-01

    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.

  5. Atmospheric Dispositifs

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2015-01-01

    , the conceptual foundations and protocols for the production of atmosphere in architecture might be found beneath the surface of contemporary debates. In this context, the notion of atmospheric dispositif – illustrated through an oeuvre of the German architect Werner Ruhnau and its theoretical and historical...... as a spatial phenomenon, exploring a multiplicity of conditions that constitute their resonant origins – i.e. the production sites from and within they have emerged. The intention is also to argue that despite the fact that atmosphere as an aesthetic category has crystallised over the last few decades...... contextualisation – provides a platform for revealing productive entanglements between heterogeneous elements, disciplines and processes. It also allows rendering atmosphere as a site of co-production open to contingencies and affective interplay on multiples levels: at the moment of its conceptualisation...

  6. Atmospheric composition

    Science.gov (United States)

    Daniels, G. E.

    1973-01-01

    The earth's atmosphere is made up of a number of gases in different relative amounts. Near sea level and up to about 90 km, the amount of these atmospheric gases in clean, relatively dry air is practically constant. Four of these gases, nitrogen, oxygen, argon, and carbon dioxide, make up 99.99 percent by volume of the atmosphere. Two gases, ozone and water vapor, change in relative amounts, but the total amount of these two is very small compared to the amount of the other gases. The atmospheric composition shown in a table can be considered valid up to 90 km geometric altitude. Above 90 km, mainly because of molecular dissociation and diffusive separation, the composition changes.

  7. 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

  8. Fast Particle Methods for Multiscale Phenomena Simulations

    Science.gov (United States)

    Koumoutsakos, P.; Wray, A.; Shariff, K.; Pohorille, Andrew

    2000-01-01

    We are developing particle methods oriented at improving computational modeling capabilities of multiscale physical phenomena in : (i) high Reynolds number unsteady vortical flows, (ii) particle laden and interfacial flows, (iii)molecular dynamics studies of nanoscale droplets and studies of the structure, functions, and evolution of the earliest living cell. The unifying computational approach involves particle methods implemented in parallel computer architectures. The inherent adaptivity, robustness and efficiency of particle methods makes them a multidisciplinary computational tool capable of bridging the gap of micro-scale and continuum flow simulations. Using efficient tree data structures, multipole expansion algorithms, and improved particle-grid interpolation, particle methods allow for simulations using millions of computational elements, making possible the resolution of a wide range of length and time scales of these important physical phenomena.The current challenges in these simulations are in : [i] the proper formulation of particle methods in the molecular and continuous level for the discretization of the governing equations [ii] the resolution of the wide range of time and length scales governing the phenomena under investigation. [iii] the minimization of numerical artifacts that may interfere with the physics of the systems under consideration. [iv] the parallelization of processes such as tree traversal and grid-particle interpolations We are conducting simulations using vortex methods, molecular dynamics and smooth particle hydrodynamics, exploiting their unifying concepts such as : the solution of the N-body problem in parallel computers, highly accurate particle-particle and grid-particle interpolations, parallel FFT's and the formulation of processes such as diffusion in the context of particle methods. This approach enables us to transcend among seemingly unrelated areas of research.

  9. Rod Driven Frequency Entrainment and Resonance Phenomena

    Directory of Open Access Journals (Sweden)

    Christina Salchow

    2016-08-01

    Full Text Available A controversy exists on photic driving in the human visual cortex evoked by intermittent photic stimulation. Frequency entrainment and resonance phenomena are reported for frequencies higher than 12 Hz in some studies while missing in others. We hypothesized that this might be due to different experimental conditions, since both high and low intensity light stimulation were used. However, most studies do not report radiometric measurements, which makes it impossible to categorize the stimulation according to photopic, mesopic, and scotopic vision. Low intensity light stimulation might lead to scotopic vision, where rod perception dominates. In this study, we investigated photic driving for rod-dominated visual input under scotopic conditions. Twelve healthy volunteers were stimulated with low intensity light flashes at 20 stimulation frequencies, leading to rod activation only. The frequencies were multiples of the individual alpha frequency (α of each volunteer in the range from 0.40–2.30*α. 306-channel whole head magnetoencephalography recordings were analyzed in time, frequency, and spatiotemporal domains with the Topographic Matching Pursuit algorithm. We found resonance phenomena and frequency entrainment for stimulations at or close to the individual alpha frequency (0.90–1.10*α and half of the alpha frequency (0.40–0.55*α. No signs of resonance and frequency entrainment phenomena were revealed around 2.00*α. Instead, on-responses at the beginning and off-responses at the end of each stimulation train were observed for the first time in a photic driving experiment at frequencies of 1.30–2.30*α, indicating that the flicker fusion threshold was reached. All results, the resonance and entrainment as well as the fusion effects, provide evidence for rod-dominated photic driving in the visual cortex.

  10. Rod Driven Frequency Entrainment and Resonance Phenomena

    Science.gov (United States)

    Salchow, Christina; Strohmeier, Daniel; Klee, Sascha; Jannek, Dunja; Schiecke, Karin; Witte, Herbert; Nehorai, Arye; Haueisen, Jens

    2016-01-01

    A controversy exists on photic driving in the human visual cortex evoked by intermittent photic stimulation. Frequency entrainment and resonance phenomena are reported for frequencies higher than 12 Hz in some studies while missing in others. We hypothesized that this might be due to different experimental conditions, since both high and low intensity light stimulation were used. However, most studies do not report radiometric measurements, which makes it impossible to categorize the stimulation according to photopic, mesopic, and scotopic vision. Low intensity light stimulation might lead to scotopic vision, where rod perception dominates. In this study, we investigated photic driving for rod-dominated visual input under scotopic conditions. Twelve healthy volunteers were stimulated with low intensity light flashes at 20 stimulation frequencies, leading to rod activation only. The frequencies were multiples of the individual alpha frequency (α) of each volunteer in the range from 0.40 to 2.30∗α. Three hundred and six-channel whole head magnetoencephalography recordings were analyzed in time, frequency, and spatiotemporal domains with the Topographic Matching Pursuit algorithm. We found resonance phenomena and frequency entrainment for stimulations at or close to the individual alpha frequency (0.90–1.10∗α) and half of the alpha frequency (0.40–0.55∗α). No signs of resonance and frequency entrainment phenomena were revealed around 2.00∗α. Instead, on-responses at the beginning and off-responses at the end of each stimulation train were observed for the first time in a photic driving experiment at frequencies of 1.30–2.30∗α, indicating that the flicker fusion threshold was reached. All results, the resonance and entrainment as well as the fusion effects, provide evidence for rod-dominated photic driving in the visual cortex. PMID:27588002

  11. 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.

  12. 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)

  13. 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.

  14. 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.

  15. 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

  16. Autistic phenomena in The Adventures of Pinocchio.

    Science.gov (United States)

    Smith, Adrian

    2017-04-01

    This paper seeks to demonstrate that the protagonist of Carlo Collodi's The Adventures of Pinocchio illustrates numerous autistic phenomena such as communication difficulties, sensory and perceptual distortions and mindblindness. While Pinocchio is viewed as a literary construct with contraindications of autism, it will be argued that his autistic traits are sufficient to suggest the possibility that Collodi had a partial intuition of the syndrome 60 years before it was identified by Leo Kanner. Approaching Collodi's text in this manner is taken as an opportunity to survey and reflect upon the psychoanalytic literature on autism and to position it in relation to contemporary theories from cognitive neuroscience.

  17. BEAM COUPLING PHENOMENA IN FAST KICKER SYSTEMS.

    Energy Technology Data Exchange (ETDEWEB)

    ZHANG,W.; AHRENS,L.A.; GLENN,J.; SANDBERG,J.; TSOUPAS,N.

    2001-06-18

    Beam coupling phenomena have been observed in most fast kicker systems through out Brookhaven Collider-Accelerator complex. With ever-higher beam intensity, the signature of the beam becomes increasingly recognizable. The beam coupling at high intensity produced additional heat dissipation in high voltage modulator, thyratron grids, thyratron driver circuit sufficient to damage some components, and causes trigger instability. In this paper, we will present our observations, basic coupling mode analysis, relevance to the magnet structures, issues related to the existing high voltage modulators, and considerations of the future design of the fast kicker systems.

  18. Interfacial Phenomena and Natural Local Time

    CERN Document Server

    Appuhamillage, Thilanka; Thomann, Enrique; Waymire, Edward; Wood, Brian

    2012-01-01

    This article addresses a modification of local time for stochastic processes, to be referred to as `natural local time'. It is prompted by theoretical developments arising in mathematical treatments of recent experiments and observations of phenomena in the geophysical and biological sciences pertaining to dispersion in the presence of an interface of discontinuity in dispersion coefficients. The results illustrate new ways in which to use the theory of stochastic processes to infer macro scale parameters and behavior from micro scale observations in particular heterogeneous environments.

  19. 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

  20. Atmospheric thermodynamics

    CERN Document Server

    Iribarne, J V

    1973-01-01

    The thermodynamics of the atmosphere is the subject of several chapters in most textbooks on dynamic meteorology, but there is no work in English to give the subject a specific and more extensive treatment. In writing the present textbook, we have tried to fill this rather remarkable gap in the literature related to atmospheric sciences. Our aim has been to provide students of meteorology with a book that can playa role similar to the textbooks on chemical thermodynamics for the chemists. This implies a previous knowledge of general thermodynamics, such as students acquire in general physics courses; therefore, although the basic principles are reviewed (in the first four chapters), they are only briefly discussed, and emphasis is laid on those topics that will be useful in later chapters, through their application to atmospheric problems. No attempt has been made to introduce the thermodynamics of irreversible processes; on the other hand, consideration of heterogeneous and open homogeneous systems permits a...

  1. AN ANTHOLOGY OF THE DISTINGUISHED ACHIEVEMENTS IN SCIENCE AND TECHNIQUE. PART 29: DISCOVERERS OF SECRETS OF GLOBAL NATURAL LIGHT PHENOMENA

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2015-12-01

    Full Text Available Purpose. Scientifically-historical description of features of opening by scientists-discoverers of the world of electrophysics and electrochemical secrets of such natural light phenomena as Aurora Borealis, rainbow and photosynthesis, carrying global planetary character for the habitants of planet Earth. Methodology. Scientific approaches at treatment and systematization of physical knowledges about «solar wind» and sun radiation, causing flowing in the atmosphere of Earth of the indicated light phenomena. Methods of historical method at research of progressive development in the world of basic scientific knowledges about the examined natural light phenomena. Results. Basic information, touching forming of scientific bases of electrophysics and electrochemical processes, flows at a display in the earthly atmosphere of aurora north (south polaris, primary (second rainbow and photosynthesis domestic and foreign scientists in the leaves of higher (lower plants, is resulted. Originality. First in area of history of scientific and technological bases of electrophysics and electrochemical processes, characteristic for aurora polaris, rainbow and photosynthesis in an earthly magnetic sphere and air atmosphere are presented in the short systematized form and historical development. Practical value. Scientific popularization of electrophysics and electrochemical knowledges and distinguished scientific achievements in area of such global for a planet Earth of the natural atmospheric light phenomena as aurora Borealis, rainbow and photosynthesis.

  2. 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.

  3. Emergent phenomena and partonic structure in hadrons

    CERN Document Server

    Roberts, Craig D

    2016-01-01

    Modern facilities are poised to tackle fundamental questions within the Standard Model, aiming to reveal the nature of confinement, its relationship to dynamical chiral symmetry breaking (DCSB) - the origin of visible mass - and the connection between these two, key emergent phenomena. There is strong evidence to suggest that they are intimately connected with the appearance of momentum-dependent masses for gluons and quarks in QCD, which are large in the infrared: $m_g \\sim 500\\,$MeV and $M_q\\sim 350\\,$MeV. DCSB, expressed in the dynamical generation of a dressed-quark mass, has an enormous variety of verifiable consequences, including an enigmatic result that the properties of the (almost) massless pion are the cleanest expression of the mechanism which is responsible for almost all the visible mass in the Universe. This contribution explains that these emergent phenomena are expressed with particular force in the partonic structure of hadrons, e.g. in valence-quark parton distribution amplitudes and functi...

  4. Multiscale phenomena in the Earth's Magnetosphere

    Science.gov (United States)

    Surjalal Sharma, A.

    The multiscale phenomena in the Earth's magnetosphere have been studied using data from ground-based and space-borne measurements. The ground-based observations provide data over decades and are suitable for characterizing the inherent nature of the multiscale behavior and for studying the dynamical and statistical features. On the other hand, the spacecraft data provide in-situ observations of the processes. The multipoint measurements by Cluster have provided a new understanding of the plasma processes at microand meso-scales and the cross-scale coupling among them. The role of cross-scale coupling is evident in phenomena such as bursty bulk flows, flux ropes, and reconnection. The characteristic scales of the processes range from electron skin depth to MHD scales and the modeling of these processes need different physical models, such as kinetic, EMHD, Hall MHD, and MHD. The ground-based data have been used to develop models based on techniques of nonlinear science and yield predictive models which can be used for forecasting. These models characterize the magnetospheric dynaics and yield its global and multiscale aspects. The distribution of scales in the magnetosphere is studied using an extensive database of the solar wind and the magnetosphere. The distributions of the waiting times deviate significantly from a power law as well as stretched exponential distributions, and show a scaling with respect to the mean, indicating a limited role of long-term correlations in the magnetospheric dynamics.

  5. 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.

  6. Nonlinear phenomena in Bose-Einstein condensates

    Science.gov (United States)

    Carr, Lincoln D.

    2008-05-01

    We present a medley of results from the last three years on nonlinear phenomena in BECs [1]. These include exact dynamics of multi-component condensates in optical lattices [2], vortices and ring solitons [3], macroscopic quantum tunneling [4], nonlinear band theory [5], and a pulsed atomic soliton laser [6]. 1. Emergent Nonlinear Phenomena in Bose-Einstein Condensates: Theory and Experiment, ed. P. G. Kevrekidis, D. J. Frantzeskakis, and R. Carretero-Gonzalez (Springer-Verlag, 2008). 2. R. Mark Bradley, James E. Bernard, and L. D. Carr, e-print arXiv:0711.1896 (2007). 3. G. Herring, L. D. Carr, R. Carretero-Gonzalez, P. G. Kevrekidis, D. J. Frantzeskakis, Phys. Rev. A in press, e-print arXiv:0709.2193 (2007); L. D. Carr and C. W. Clark, Phys. Rev. A v. 74, p.043613 (2006); L. D. Carr and C. W. Clark, Phys. Rev. Lett. v. 97, p.010403 (2006). 4. L. D. Carr, M. J. Holland, and B. A. Malomed, J. Phys. B: At. Mol. Opt. Phys., v.38, p.3217 (2005) 5. B. T. Seaman, L. D. Carr, and M. J. Holland, Phys. Rev. A, v. 71, p.033622 (2005). 6. L. D. Carr and J. Brand, Phys. Rev. A, v.70, p.033607 (2004); L. D. Carr and J. Brand, Phys. Rev. Lett., v.92, p.040401 (2004).

  7. Atmospheric Refraction

    CERN Document Server

    Nauenberg, Michael

    2016-01-01

    Calculations of atmospheric refraction are generally based on a simplified model of atmospheric density in the troposphere which assumes that the temperature decreases at a constant lapse rate from sea level up to a height equal to eleven km, and that afterwards it remains constant. In this model, the temperature divided by the lapse rate determines the length scale in the calculations for altitudes less than this height. But daily balloon measurements across the U.S.A. reveal that in some cases the air temperature actually increases from sea level up to a height of about one km, and only after reaching a plateau, it decreases at an approximately constant lapse rate. Moreover, in three examples considered here, the temperature does not remain constant at eleven km , but continues to decreases to a minimum at about sixteen kilometers , and then increases at higher altitudes at a lower rate. Calculations of atmospheric refraction based on this atmospheric data is compared with the results of simplified models.

  8. Phenomena based Methodology for Process Synthesis incorporating Process Intensification

    DEFF Research Database (Denmark)

    Lutze, Philip; Babi, Deenesh Kavi; Woodley, John

    2013-01-01

    at processes at the lowest level of aggregation which is the phenomena level. In this paper, a phenomena based synthesis/design methodology incorporating process intensification is presented. Using this methodology, a systematic identification of necessary and desirable (integrated) phenomena as well...

  9. 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

  10. Microgravity Transport Phenomena Experiment (MTPE) Overview

    Science.gov (United States)

    Mason, Larry W.

    1999-01-01

    The Microgravity Transport Phenomena Experiment (MTPE) is a fluids experiment supported by the Fundamentals in Biotechnology program in association with the Human Exploration and Development of Space (BEDS) initiative. The MTP Experiment will investigate fluid transport phenomena both in ground based experiments and in the microgravity environment. Many fluid transport processes are affected by gravity. Osmotic flux kinetics in planar membrane systems have been shown to be influenced by gravimetric orientation, either through convective mixing caused by unstably stratified fluid layers, or through a stable fluid boundary layer structure that forms in association with the membrane. Coupled transport phenomena also show gravity related effects. Coefficients associated with coupled transport processes are defined in terms of a steady state condition. Buoyancy (gravity) driven convection interferes with the attainment of steady state, and the measurement of coupled processes. The MTP Experiment measures the kinetics of molecular migration that occurs in fluids, in response to the application of various driving potentials. Three separate driving potentials may be applied to the MTP Experiment fluids, either singly or in combination. The driving potentials include chemical potential, thermal potential, and electrical potential. Two separate fluid arrangements are used to study membrane mediated and bulk fluid transport phenomena. Transport processes of interest in membrane mediated systems include diffusion, osmosis, and streaming potential. Bulk fluid processes of interest include coupled phenomena such as the Soret Effect, Dufour Effect, Donnan Effect, and thermal diffusion potential. MTP Experiments are performed in the Microgravity Transport Apparatus (MTA), an instrument that has been developed specifically for precision measurement of transport processes. Experiment fluids are contained within the MTA fluid cells, designed to create a one dimensional flow geometry

  11. Mathematical methods of studying physical phenomena

    Science.gov (United States)

    Man'ko, Margarita A.

    2013-03-01

    In recent decades, substantial theoretical and experimental progress was achieved in understanding the quantum nature of physical phenomena that serves as the foundation of present and future quantum technologies. Quantum correlations like the entanglement of the states of composite systems, the phenomenon of quantum discord, which captures other aspects of quantum correlations, quantum contextuality and, connected with these phenomena, uncertainty relations for conjugate variables and entropies, like Shannon and Rényi entropies, and the inequalities for spin states, like Bell inequalities, reflect the recently understood quantum properties of micro and macro systems. The mathematical methods needed to describe all quantum phenomena mentioned above were also the subject of intense studies in the end of the last, and beginning of the new, century. In this section of CAMOP 'Mathematical Methods of Studying Physical Phenomena' new results and new trends in the rapidly developing domain of quantum (and classical) physics are presented. Among the particular topics under discussion there are some reviews on the problems of dynamical invariants and their relations with symmetries of the physical systems. In fact, this is a very old problem of both classical and quantum systems, e.g. the systems of parametric oscillators with time-dependent parameters, like Ermakov systems, which have specific constants of motion depending linearly or quadratically on the oscillator positions and momenta. Such dynamical invariants play an important role in studying the dynamical Casimir effect, the essence of the effect being the creation of photons from the vacuum in a cavity with moving boundaries due to the presence of purely quantum fluctuations of the electromagnetic field in the vacuum. It is remarkable that this effect was recently observed experimentally. The other new direction in developing the mathematical approach in physics is quantum tomography that provides a new vision of

  12. Establishment of the New Ecuadorian Solar Physics Phenomena Division

    Science.gov (United States)

    Lopez, E. D.

    2014-02-01

    Crucial physical phenomena occur in the equatorial atmosphere and ionosphere, which are currently understudied and poorly understood. Thus, scientific campaigns for monitoring the equatorial region are required in order to provide the necessary data for the physical models. Ecuador is located in strategic geographical position where these studies can be performed, providing quality data for the scientific community working in understanding the nature of these physical systems. The Quito Astronomical Observatory of National Polytechnic School is moving in this direction by promoting research in space sciences for the study of the equatorial zone. With the participation and the valuable collaboration of international initiatives such us AWESOME, MAGDAS, SAVNET and CALLISTO, the Quito Observatory is establishing a new space physics division on the basis of the International Space Weather Initiative. In this contribution, the above initiative is presented by inviting leaders of other scientific projects to deploy its instruments and to work with us providing the necessary support to the creation of this new strategic research center

  13. Collective phenomena in volume and surface barrier discharges

    Science.gov (United States)

    Kogelschatz, U.

    2010-11-01

    Barrier discharges are increasingly used as a cost-effective configuration to produce non-equilibrium plasmas at atmospheric pressure. This way, copious amounts of electrons, ions, free radicals and excited species can be generated without significant heating of the background gas. In most applications the barrier is made of dielectric material. Major applications utilizing mainly dielectric barriers include ozone generation, surface cleaning and modification, polymer and textile treatment, sterilization, pollution control, CO2 lasers, excimer lamps, plasma display panels (flat TV screens). More recent research efforts are devoted to biomedical applications and to plasma actuators for flow control. Sinusoidal feeding voltages at various frequencies as well as pulsed excitation schemes are used. Volume as well as surface barrier discharges can exist in the form of filamentary, regularly patterned or diffuse, laterally homogeneous discharges. The physical effects leading to collective phenomena in volume and surface barrier discharges are discussed in detail. Special attention is paid to self-organization of current filaments and pattern formation. Major similarities of the two types of barrier discharges are elaborated.

  14. The global atmospheric electrical circuit and climate

    CERN Document Server

    Harrison, R G

    2004-01-01

    Evidence is emerging for physical links among clouds, global temperatures, the global atmospheric electrical circuit and cosmic ray ionisation. The global circuit extends throughout the atmosphere from the planetary surface to the lower layers of the ionosphere. Cosmic rays are the principal source of atmospheric ions away from the continental boundary layer: the ions formed permit a vertical conduction current to flow in the fair weather part of the global circuit. Through the (inverse) solar modulation of cosmic rays, the resulting columnar ionisation changes may allow the global circuit to convey a solar influence to meteorological phenomena of the lower atmosphere. Electrical effects on non-thunderstorm clouds have been proposed to occur via the ion-assisted formation of ultrafine aerosol, which can grow to sizes able to act as cloud condensation nuclei, or through the increased ice nucleation capability of charged aerosols. Even small atmospheric electrical modulations on the aerosol size distribution ca...

  15. Density-functional theory of thermoelectric phenomena.

    Science.gov (United States)

    Eich, F G; Di Ventra, M; Vignale, G

    2014-05-16

    We introduce a nonequilibrium density-functional theory of local temperature and associated local energy density that is suited for the study of thermoelectric phenomena. The theory rests on a local temperature field coupled to the energy-density operator. We identify the excess-energy density, in addition to the particle density, as the basic variable, which is reproduced by an effective noninteracting Kohn-Sham system. A novel Kohn-Sham equation emerges featuring a time-dependent and spatially varying mass which represents local temperature variations. The adiabatic contribution to the Kohn-Sham potentials is related to the entropy viewed as a functional of the particle and energy density. Dissipation can be taken into account by employing linear response theory and the thermoelectric transport coefficients of the electron gas.

  16. 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)

  17. Modeling electrical dispersion phenomena in Earth materials

    Directory of Open Access Journals (Sweden)

    D. Patella

    2008-06-01

    Full Text Available It is illustrated that IP phenomena in rocks can be described using conductivity dispersion models deduced as solutions to a 2nd-order linear differential equation describing the motion of a charged particle immersed in an external electrical field. Five dispersion laws are discussed, namely: the non-resonant positive IP model, which leads to the classical Debye-type dispersion law and by extension to the Cole-Cole model, largely used in current practice; the non-resonant negative IP model, which allows negative chargeability values, known in metals at high frequencies, to be explained as an intrinsic physical property of earth materials in specific field cases; the resonant flat, positive or negative IP models, which can explain the presence of peak effects at specific frequencies superimposed on flat, positive or negative dispersion spectra.

  18. Laser Interaction and Related Plasma Phenomena

    Directory of Open Access Journals (Sweden)

    Frederick Osman

    2005-01-01

    Full Text Available Computations are to be performed using the laser driven inertial fusion energy option based on volume ignition with the natural adiabatic self-similarity compression and expansion hydrodynamics [1]. The numerical work includes the establishing of a multi-branch reaction code to be used for simultaneous fusion reactions of D-D, D-T D-He3 and mutual nuclear reaction products. This will permit the studies of neutron lean reactions as well as tritium-rich cases. The D-T reactions will stress the recent new results on one step laser fusion [2] as an alternative to the two-step fast ignitor scheme whose difficulties with new physics phenomena at petawatt laser interaction are more and more evident [3].

  19. Transitional Phenomena on Phase Change Materials

    Directory of Open Access Journals (Sweden)

    Wójcik Tadeusz M.

    2014-03-01

    Full Text Available One of the most significant problem with technology development is transferring of large heat fluxes, which requires constant heat transfer temperature (in the specified temperature range. This problem concern mainly the nuclear energetics, space technologies, military technologies and most of all electronics containing integrated circuits with very large scale of integrations. Intensive heat transfer and thermal energy storage are possible by the use of phase change materials (PCMs. In the paper there are presented preliminary results of research on the use of liquid-gas (L-G PCMs and solid-solid phase change materials (S-S PCMs. For L-G PCMs the boiling characteristics were determined by increasing and decreasing the heat flux, which for certain sets of structural parameters of the heating surface and the physical properties of the liquid induce a variety of forms of transitional phenomena. Thermal energy storage is much more effective when using PCMs than sensible heat.

  20. Heat Transfer Phenomena of Supercritical Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Krau, Carmen Isabella; Kuhn, Dietmar; Schulenberg, Thomas [Forschungszentrum Karlsruhe, Institute for Nuclear and Energy Technologies, 76021 Karlsruhe (Germany)

    2008-07-01

    In concepts for supercritical water cooled reactors, the reactor core is cooled and moderated by water at supercritical pressures. The significant temperature dependence of the fluid properties of water requires an exact knowledge of the heat transfer mechanism to avoid fuel pin damages. Near the pseudo-critical point a deterioration of heat transfer might happen. Processes, that take place in this case, are not fully understood and are due to be examined systematically. In this paper a general overview on the properties of supercritical water is given, experimental observations of different authors will be reviewed in order to identify heat transfer phenomena and onset of occurrence. The conceptional design of a test rig to investigate heat transfer in the boundary layer will be discussed. Both, water and carbon dioxide, may serve as operating fluids. The loop, including instrumentation and safety devices, is shown and suitable measuring methods are described. (authors)

  1. Instability phenomena in plasticity: Modelling and computation

    Science.gov (United States)

    Stein, E.; Steinmann, P.; Miehe, C.

    1995-12-01

    We presented aspects and results related to the broad field of strain localization with special focus on large strain elastoplastic response. Therefore, we first re-examined issues related to the classification of discontinuities and the classical description of localization with a particular emphasis on an Eulerian geometric representation. We touched the problem of mesh objectivity and discussed results of a particular regularization method, namely the micropolar approach. Generally, regularization has to preserve ellipticity and to reflect the underlying physics. For example ductile materials have to be modelled including viscous effects whereas geomaterials are adequately described by the micropolar approach. Then we considered localization phenomena within solids undergoing large strain elastoplastic deformations. Here, we documented the influence of isotropic damage on the failure analysis. Next, the interesting influence of an orthotropic yield condition on the spatial orientation of localized zones has been studied. Finally, we investigated the localization condition for an algorithmic model of finite strain single crystal plasticity.

  2. Noise-driven phenomena in hysteretic systems

    CERN Document Server

    Dimian, Mihai

    2014-01-01

    Noise-Driven Phenomena in Hysteretic Systems provides a general approach to nonlinear systems with hysteresis driven by noisy inputs, which leads to a unitary framework for the analysis of various stochastic aspects of hysteresis. This book includes integral, differential and algebraic models that are used to describe scalar and vector hysteretic nonlinearities originating from various areas of science and engineering. The universality of the authors approach is also reflected by the diversity of the models used to portray the input noise, from the classical Gaussian white noise to its impulsive forms, often encountered in economics and biological systems, and pink noise, ubiquitous in multi-stable electronic systems. The book is accompanied by HysterSoft© - a robust simulation environment designed to perform complex hysteresis modeling – that can be used by the reader to reproduce many of the results presented in the book as well as to research both disruptive and constructive effects of noise in hysteret...

  3. Electron Acceleration by Transient Ion Foreshock Phenomena

    Science.gov (United States)

    Wilson, L. B., III; Turner, D. L.

    2015-12-01

    Particle acceleration is a topic of considerable interest in space, laboratory, and astrophysical plasmas as it is a fundamental physical process to all areas of physics. Recent THEMIS [e.g., Turner et al., 2014] and Wind [e.g., Wilson et al., 2013] observations have found evidence for strong particle acceleration at macro- and meso-scale structures and/or pulsations called transient ion foreshock phenomena (TIFP). Ion acceleration has been extensively studied, but electron acceleration has received less attention. Electron acceleration can arise from fundamentally different processes than those affecting ions due to differences in their gyroradii. Electron acceleration is ubiquitous, occurring in the solar corona (e.g., solar flares), magnetic reconnection, at shocks, astrophysical plasmas, etc. We present new results analyzing the dependencies of electron acceleration on the properties of TIFP observed by the THEMIS spacecraft.

  4. Simulating Physical Phenomena by Quantum Networks

    CERN Document Server

    Somma, R D; Gubernatis, J E; Knill, E H; Laflamme, R

    2002-01-01

    Physical systems, characterized by an ensemble of interacting elementary constituents, can be represented and studied by different algebras of observables or operators. For example, a fully polarized electronic system can be investigated by means of the algebra generated by the usual fermionic creation and annihilation operators, or by using the algebra of Pauli (spin-1/2) operators. The correspondence between the two algebras is given by the Jordan-Wigner isomorphism. As we previously noted similar one-to-one mappings enable one to represent any physical system in a quantum computer. In this paper we evolve and exploit this fundamental concept in quantum information processing to simulate generic physical phenomena by quantum networks. We give quantum circuits useful for the efficient evaluation of the physical properties (e.g, spectrum of observables or relevant correlation functions) of an arbitrary system with Hamiltonian $H$.

  5. Surfactant-based critical phenomena in microgravity

    Science.gov (United States)

    Kaler, Eric W.; Paulaitis, Michael E.

    1994-01-01

    The objective of this research project is to characterize by experiment and theoretically both the kinetics of phase separation and the metastable structures produced during phase separation in a microgravity environment. The particular systems we are currently studying are mixtures of water, nonionic surfactants, and compressible supercritical fluids at temperatures and pressures where the coexisting liquid phases have equal densities (isopycnic phases). In this report, we describe experiments to locate equilibrium isopycnic phases and to determine the 'local' phase behavior and critical phenomena at nearby conditions of temperature, pressure, and composition. In addition, we report the results of preliminary small angle neutron scattering (SANS) experiments to characterize microstructures that exist in these mixtures at different fluid densities.

  6. Stochastic phenomena in a fiber Raman amplifier

    CERN Document Server

    Kalashnikov, Vladimir; Ania-Castanón, Juan Diego; Jacobsen, Gunnar; Popov, Sergei

    2016-01-01

    The interplay of such cornerstones of modern nonlinear fiber optics as a nonlinearity, stochasticity and polarization leads to variety of the noise induced instabilities including polarization attraction and escape phenomena harnessing of which is a key to unlocking the fiber optic systems specifications required in high resolution spectroscopy, metrology, biomedicine and telecommunications. Here, by using direct stochastic modeling, the mapping of interplay of the Raman scattering-based nonlinearity, the random birefringence of a fiber, and the pump-to-signal intensity noise transfer has been done in terms of the fiber Raman amplifier parameters, namely polarization mode dispersion, the relative intensity noise of the pump laser, fiber length, and the signal power. The obtained results reveal conditions for emergence of the random birefringence-induced resonance-like enhancement of the gain fluctuations (stochastic anti-resonance) accompanied by pulse broadening and rare events in the form of low power outpu...

  7. Peridynamic Formulation for Coupled Thermoelectric Phenomena

    Directory of Open Access Journals (Sweden)

    Migbar Assefa

    2017-01-01

    Full Text Available Modeling of heat and electrical current flow simultaneously in thermoelectric convertor using classical theories do not consider the influence of defects in the material. This is because traditional methods are developed based on partial differential equations (PDEs and lead to infinite fluxes at the discontinuities. The usual way of solving such PDEs is by using numerical technique, like Finite Element Method (FEM. Although FEM is robust and versatile, it is not suitable to model evolving discontinuities. To avoid such shortcomings, we propose the concept of peridynamic theory to derive the balance of energy and charge equations in the coupled thermoelectric phenomena. Therefore, this paper presents the transport of heat and charge in thermoelectric material in the framework of peridynamic (PD theory. To illustrate the reliability of the PD formulation, numerical examples are presented and results are compared with those from literature, analytical solutions, or finite element solutions.

  8. Hadronic and nuclear phenomena in quantum chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.J.

    1987-06-01

    Many of the key issues in understanding quantum chromodynamics involves processes at intermediate energies. We discuss a range of hadronic and nuclear phenomena - exclusive processes, color transparency, hidden color degrees of freedom in nuclei, reduced nuclear amplitudes, jet coalescence, formation zone effects, hadron helicity selection rules, spin correlations, higher twist effects, and nuclear diffraction - as tools for probing hadron structure and the propagation of quark and gluon jets in nuclei. Many of these processes can be studied in electroproduction, utilizing internal targets in storage rings. We also review several areas where there has been significant theoretical progress in determining the form of hadron and nuclear wavefunctions, including QCD sum rules, lattice gauge theory, and discretized light-cone quantization. 98 refs., 40 figs., 2 tabs.

  9. Microdevices enabled by rarefied flow phenomena

    Science.gov (United States)

    Alexeenko, Alina A.; Strongrich, A. D.; Cofer, A. G.; Pikus, A.; Sebastiao, I. B.; Tholeti, S. S.; Shivkumar, G.

    2016-11-01

    In this paper we review emerging applications of rarefied gas dynamics for microscale sensing, actuation, power generation and thermal management. The performance of conventional fluidic devices such as pumps, combustors and heat engines drops with the decrease of characteristic length scale due to greater viscous and heat transfer losses. However, the close coupling between non-equilibrium gas, liquid and solid-state transport and electromagnetic phenomena enables unconventional micro/nanodevices. We specifically consider three distinct examples of devices with non-equilibrium gas-phase transport based on i) very large thermal gradients; ii) increased capillary forces; iii) high electric fields - all of which are generated by scaling down device size by using nano/micromanufacturing techniques.

  10. Corporate Strategy And The Social Networking Phenomena

    Directory of Open Access Journals (Sweden)

    Robert L. Johnson

    2011-11-01

    Full Text Available The Social Networking (SN phenomena has developed relatively overnight and is continuing to develop at an exponential pace. It allows for innovative new methods of disseminating and collecting information in ways never before dreamed possible by corporate executives. The rise of Social Networking is becoming a disruptive technology for traditional marketing and advertising medium such as radio, television, web page, and print media, creating new business opportunities for the entrepreneur within organizations of any size, and allowing lucrative treasure troves of corporate intelligence about how the customers feel about one’s or a competitor’s products or services. It means new executive leadership skills are now needed to take advantage of these new tools and developing corporate strategies. Those that do this well will be the winners in the market five years from now.

  11. Nonmodal phenomena in differentially rotating dusty plasmas

    Science.gov (United States)

    Poedts, Stefaan; Rogava, Andria D.

    2000-10-01

    In this paper the foundation is layed for the nonmodal investigation of velocity shear induced phenomena in a differentially rotating flow of a dusty plasma. The simplest case of nonmagnetized flow is considered. It is shown that, together with the innate properties of the dusty plasma, the presence of differential rotation, Coriolis forces, and self-gravity casts a considerable richness on the nonmodal dynamics of linear perturbations in the flow. In particular: (i) dust-acoustic waves acquire the ability to extract energy from the mean flow and (ii) shear-induced, nonperiodic modes of collective plasma behavior-shear-dust-acoustic vortices-are generated. The presence of self-gravity and the nonzero Coriolis parameter (``epicyclic shaking'') makes these collective modes transiently unstable. .

  12. 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.

  13. PHENOMENA AND BASIC MACROECONOMIC INDICATORS FOR MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    PAULINA CATANA

    2010-01-01

    Full Text Available Macroeconomics is a separate discipline of the Economy that studies and analyzes the behaviour of economic aggregates and significant average, such as price level, national income, national income potential, the gap GDP, employment and unemployment of labour, investment and export of the whole economy. We can accuse to Macroeconomics that it deals also with the average price of all goods and services, not the prices of certain products. These aggregates result from economic behaviour of certain groups (governments, companies, consumers in the course of their activities on different markets. But why does it need Macroeconomics? Experts say that we need this separate discipline because there are certain forces that affect the broader economy globally, which can not be understood only by analyzing individual economic phenomena, individual products or markets.

  14. Novel nuclear phenomena in quantum chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.J.

    1987-08-01

    Many of the key issues in understanding quantum chromodynamics involve processes in nuclear targets at intermediate energies. A range of hadronic and nuclear phenomena-exclusive processes, color transparency, hidden color degrees of freedom in nuclei, reduced nuclear amplitudes, jet coalescence, formation zone effects, hadron helicity selection rules, spin correlations, higher twist effects, and nuclear diffraction were discussed as tools for probing hadron structure and the propagation of quark and gluon jets in nuclei. Several areas were also reviewed where there has been significant theoretical progress determining the form of hadron and nuclear wave functions, including QCD sum rules, lattice gauge theory, and discretized light-cone quantization. A possible interpretation was also discussed of the large spin correlation A/sub NN/ in proton-proton scattering, and how relate this effect to an energy and angular dependence of color transparency in nuclei. 76 refs., 24 figs.

  15. Issues about the nocebo phenomena in clinics

    Institute of Scientific and Technical Information of China (English)

    WU Zhen-yu; LI Kang

    2009-01-01

    @@ During clinical work, some side-effects may occur to patients, part of which are caused by the specific pharmacological effects of drugs and some of which are non-specific. Although these phenomena happen from time to time, burdening the anguish and expenditure of patients, their nature is still less understood. Recently, as the research of the placebo effect become deeper and deeper, clinicians and researchers have gradually realized that mind plays an important role in the occurrence of non-specific side-effects, which is called "nocebo effect" professionally, the evil side of placebo effect. This article would expatiate on nocebo effect in detail from several aspects, such as its mechanism, effect, influencing factors and discuss how to make it known and treated in clinical practice and clinical trials.

  16. Social phenomena from data analysis to models

    CERN Document Server

    Perra, Nicola

    2015-01-01

    This book focuses on the new possibilities and approaches to social modeling currently being made possible by an unprecedented variety of datasets generated by our interactions with modern technologies. This area has witnessed a veritable explosion of activity over the last few years, yielding many interesting and useful results. Our aim is to provide an overview of the state of the art in this area of research, merging an extremely heterogeneous array of datasets and models. Social Phenomena: From Data Analysis to Models is divided into two parts. Part I deals with modeling social behavior under normal conditions: How we live, travel, collaborate and interact with each other in our daily lives. Part II deals with societal behavior under exceptional conditions: Protests, armed insurgencies, terrorist attacks, and reactions to infectious diseases. This book offers an overview of one of the most fertile emerging fields bringing together practitioners from scientific communities as diverse as social sciences, p...

  17. Critical Phenomena in Liquid-Liquid Mixtures

    Science.gov (United States)

    Jacobs, D. T.

    2000-04-01

    Critical phenomena provide intriguing and essential insight into many issues in condensed matter physics because of the many length scales involved. Large density or concentration fluctuations near a system's critical point effectively mask the identity of the system and produce universal phenomena that have been well studied in simple liquid-vapor and liquid-liquid systems. Such systems have provided useful model systems to test theoretical predictions which can then be extended to more complicated systems. Along various thermodynamic paths, several quantities exhibit a simple power-law dependence close to the critical point. The critical exponents describing these relationships are universal and should depend only on a universality class determined by the order-parameter and spatial dimensionality of the system. Liquid gas, binary fluid mixtures, uniaxial ferromagnetism, polymer-solvent, and protein solutions all belong to the same (Ising model) universality class. The diversity of critical systems that can be described by universal relations indicates that experimental measurements on one system should yield the same information as on another. Our experimental investigations have tested existing theory and also extended universal behavior into new areas. By measuring the coexistence curve, heat capacity, thermal expansion and static light scattering (turbidity) in various liquid-liquid and polymer-solvent systems, we have determined critical exponents and amplitudes that have sometimes confirmed and other times challenged current theory. Recent experiments investigating the heat capacity and light scattering in a liquid-liquid mixture very close to the critical point will be discussed. This research is currently supported by The Petroleum Research Fund and by NASA grant NAG8-1433 with some student support from NSF-DMR 9619406.

  18. Atmospheric Neutrinos

    CERN Document Server

    Gaisser, Thomas K

    2016-01-01

    In view of the observation by IceCube of high-energy astrophysical neutrinos, it is important to quantify the uncertainty in the background of atmospheric neutrinos. There are two sources of uncertainty, the imperfect knowledge of the spectrum and composition of the primary cosmic rays that produce the neutrinos and the limited understanding of hadron production, including charm, at high energy. This paper is an overview of both aspects.

  19. Different atmospheric effects causing FSO link attenuation: experimental results and modelling in Czech Republic

    Science.gov (United States)

    Fiser, Ondrej; Brazda, Vladimir; Wilfert, Otakar

    2015-10-01

    The four year FSO link attenuation measurement concurrently with most important meteorological parameters was performed at our mountain observatory Milesovka. In this contribution we summarize and classify different atmospheric phenomena after the FSO link attenuation quantity. For all particular phenomena the CD curves, typical events and simple dependences on relevant atmospheric parameter(s) are presented. We consider the following phenomena (approximate specific attenuation in dB/km in brackets): 1. Fog and cloud (hundreds dB/km) 2. Rain and snow (tens dB/km) 3. Atmospheric turbulence (unit dB) 4. Clear air attenuation due to water vapour (unit dB or less)

  20. Simulation of Magnetic Phenomena at Realistic Interfaces

    KAUST Repository

    Grytsyuk, Sergiy

    2016-02-04

    In modern technology exciting developments are related to the ability to understand and control interfaces. Particularly, magnetic interfaces revealing spindependent electron transport are of great interest for modern spintronic devices, such as random access memories and logic devices. From the technological point of view, spintronic devices based on magnetic interfaces enable manipulation of the magnetism via an electric field. Such ability is a result of the different quantum effects arising from the magnetic interfaces (for example, spin transfer torque or spin-orbit torque) and it can reduce the energy consumption as compared to the traditional semiconductor electronic devices. Despite many appealing characteristics of these materials, fundamental understanding of their microscopic properties and related phenomena needs to be established by thorough investigation. In this work we implement first principles calculations in order to study the structural, electric, and magnetic properties as well as related phenomena of two types of interfaces with large potential in spintronic applications: 1) interfaces between antiferromagnetic 3d-metal-oxides and ferromagnetic 3d-metals and 2) interfaces between non-magnetic 5d(4d)- and ferromagnetic 3d-metals. A major difficulty in studying such interfaces theoretically is the typically large lattice mismatch. By employing supercells with Moir e patterns, we eliminate the artificial strain that leads to doubtful results and are able to describe the dependence of the atomic density at the interfaces on the component materials and their thicknesses. After establishing understanding about the interface structures, we investigate the electronic and magnetic properties. A Moir e supercell with transition layer is found to reproduce the main experimental findings and thus turns out to be the appropriate model for simulating magnetic misfit interfaces. In addition, we systematically study the magnetic anisotropy and Rashba band

  1. Living matter: the "lunar eclipse" phenomena.

    Science.gov (United States)

    Korpan, Nikolai N

    2010-01-01

    The present investigations describe a unique phenomenon, namely the phenomenon of the "lunar eclipse", which has been observed and discovered by the author in living substance during the freeze-thawing processes in vivo using temperatures of various intensities and its cryosurgical response in animal experiment. Similar phenomena author has observed in nature, namely the total lunar eclipse and total solar eclipse. In this experimental study 76 animals (mongrel dogs) were investigated. A disc cryogenic probe was placed on the pancreas after the laparotomy. For cryosurgical exposure a temperature range of -40 degrees C, -80 degrees C, -120 degrees C and -180 degrees C was selected in contact with pancreas parenchyma. The freeze-thaw cycle was monitored by intraoperative ultrasound before, during and after cryosurgery. Each cryolesion was observed for one hour after thawing intraoperatively. Immediately after freezing, during the thawing process, the snow-white pancreas parenchyma, frozen hard to an ice block and resembling a full moon with a sharp demarcation line, gradually assumed a ruby-red shade and a hemispherical shape as it grew in size depend on reconstruction vascular circulation from the periphery to the center. This snow-white cryogenic lesion dissolved in the same manner in all animal tissues. The "lunar eclipse" phenomenon contributes to a fundamental understanding of the mechanisms of biological tissue damage during low temperature exposure in cryoscience and cryomedicine. Properties of the pancreas parenchyma response during the phenomenon of the "lunar eclipse" provide important insights into the mechanisms of damage and the formation of cryogenic lesion immediately after thawing in cryosurgery. Vascular changes and circulatory stagnation are commonly considered to be the main mechanism of biological tissue injury during low temperature exposure. The phenomenon of the "lunar eclipse" suggests that cryosurgery is the first surgical technique to use

  2. Alarming atmospheres

    DEFF Research Database (Denmark)

    Højlund, Marie; Kinch, Sofie

    2014-01-01

    . As a response to this situation, our design artefact, the interactive furniture Kidkit, invites children to become accustomed to the alarming sounds sampled from the ward while they are waiting in the waiting room. Our design acknowledges how atmospheres emerge as temporal negotiations between the rhythms......, a familiar relationship with the alarming sounds in the ward, enabling her to focus later more on the visit with the relative. The article discusses the proposed design strategy behind this solution and the potentiality for its use in hospital environments in general....

  3. Attractors, bifurcations, & chaos nonlinear phenomena in economics

    CERN Document Server

    Puu, Tönu

    2003-01-01

    The present book relies on various editions of my earlier book "Nonlinear Economic Dynamics", first published in 1989 in the Springer series "Lecture Notes in Economics and Mathematical Systems", and republished in three more, successively revised and expanded editions, as a Springer monograph, in 1991, 1993, and 1997, and in a Russian translation as "Nelineynaia Economicheskaia Dinamica". The first three editions were focused on applications. The last was differ­ ent, as it also included some chapters with mathematical background mate­ rial -ordinary differential equations and iterated maps -so as to make the book self-contained and suitable as a textbook for economics students of dynamical systems. To the same pedagogical purpose, the number of illus­ trations were expanded. The book published in 2000, with the title "A ttractors, Bifurcations, and Chaos -Nonlinear Phenomena in Economics", was so much changed, that the author felt it reasonable to give it a new title. There were two new math­ ematics ch...

  4. Novel experimentally observed phenomena in soft matter

    Indian Academy of Sciences (India)

    Ranjini Bandyopadhyan

    2013-07-01

    Soft materials such as colloidal suspensions, polymer solutions and liquid crystals are constituted by mesoscopic entities held together by weak forces. Their mechanical moduli are several orders of magnitude lower than those of atomic solids. The application of small to moderate stresses to these materials results in the disruption of their microstructures. 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, such as turbulent drag reduction, elastic turbulence, the formation of shear bands and the existence of rheological chaos, flow-induced birefringence and the unusual rheology of soft glassy materials, are reviewed. The focus then shifts to observations of the liquid-like response of granular media that have been subjected to external forces. The article concludes with examples of the patterns that emerge when certain soft materials are vibrated, or when they are displaced with Newtonian fluids of lower viscosities.

  5. Highly energetic phenomena in water electrolysis

    Science.gov (United States)

    Postnikov, A. V.; Uvarov, I. V.; Lokhanin, M. V.; Svetovoy, V. B.

    2016-12-01

    Water electrolysis performed in microsystems with a fast change of voltage polarity produces optically invisible nanobubbles containing H2 and O2 gases. In this form the gases are able to the reverse reaction of water formation. Here we report extreme phenomena observed in a millimeter-sized open system. Under a frequency of driving pulses above 100 kHz the process is accompanied by clicking sounds repeated every 50 ms or so. Fast video reveals that synchronously with the click a bubble is growing between the electrodes which reaches a size of 300 μm in 50 μs. Detailed dynamics of the system is monitored by means of a vibrometer by observing a piece of silicon floating above the electrodes. The energy of a single event is estimated as 0.3 μJ and a significant part of this energy is transformed into mechanical work moving the piece. The observations are explained by the combustion of hydrogen and oxygen mixture in the initial bubble with a diameter of about 40 μm. Unusual combustion mechanism supporting spontaneous ignition at room temperature is responsible for the process. The observed effect demonstrates a principal possibility to build a microscopic internal combustion engine.

  6. Half collision resonance phenomena in molecules

    Energy Technology Data Exchange (ETDEWEB)

    Maximo Garcia-Sucre (Universidad Central de Venezuela, Caracas (Venezuela)); Raseev, G. (Paris-11 Univ., 91 - Orsay (France)); Ross, S.C. (New Brunswick Univ., Fredericton, NB (Canada)) (eds.)

    1991-01-01

    The Escuela Latinoamericana de Fisica (ELAF) is a series of meeting s that for 28 years has played an important role in research-level teaching of physics in Latin America. This book contains the proceedings of ELAF 90 which was held at the Instituto Venezolano de Investigaciones Cientificas (IVIC) in Caracas, Venezuela from July 23 to August 3, 1990, as part of the commemoration of the 30th anniversary of IVIC. In contrast to previous ELAF's that were of general scope, ELAF 90 centered on a particular subject matter: Half Collisional Resonance Phenomena in Molecules, Experimental and Theoretical Approaches. The term Half Collision'' refers to the fragmentation of a molecular system following is excitation by light. The lack of an incident fragmentation of a molecular system following is excitation by light. The lack of an incident particle (other than the photon) in the fragmentation process is what leads to the term. The purpose of this volume is to present current results in the experimental and theoretical study of half collisions and also to include pedagogical papers at an introductory or intermediate level. The contributions are grouped into several sections; light sources; ionization; dissociation-experimental; dissociation-theory; competition between ionization and dissociation; and particle-molecule collisions.

  7. Imaging unsteady three-dimensional transport phenomena

    Indian Academy of Sciences (India)

    K Muralidhar

    2014-01-01

    Careful and continuous measurements of flow, heat and mass transfer are required in quite a few contexts. Using appropriate light sources, it is possible to map velocity, temperature, and species concentration over a cross-section and as a function of time. Image formation in optical measurements may rely on scattering of radiation from particles. Alternatively, if the region of interest is transparent, refractive index would be a field variable and beam bending effects can be used to extract information about temperature and concentration of solutes dissolved in liquids. Time-lapsed images of light intensity can be used to determine fluid velocity. Though used originally for flow visualization, optical imaging has now emerged as a powerful tool for quantitative measurements. Optical methods that utilize the dependence of refractive index on concentration and temperature can be configured in many different ways. Three available routes considered are interferometry, schlieren imaging, and shadowgraph. Images recorded in these configurations can be analysed to yield time sequences of three-dimensional distributions of the transported variables. Optical methods are non-intrusive, inertia-free and can image cross-sections of the experimental apparatus. The image data can be jointly analysed with the physical laws governing transport and principles of image formation. Hence, with the experiment suitably carried out, three-dimensional physical domains with unsteady processes can be accommodated. Optical methods promise to breach the holy grail of measurements by extracting unsteady three-dimensional data in applications related to transport phenomena.

  8. JET: Recent results and edge phenomena

    Energy Technology Data Exchange (ETDEWEB)

    De Kock, L.; Behringer, K.; Bickerton, R.J.; Boschi, A.; Brinkschulte, H.; Bures, M.; Campbell, D.J.; Christiansen, J.; Cordey, J.G.; Coad, J.P.

    1987-02-01

    Ohmic heating studies in hydrogen and deuterium up to currents of I/sub p/ = 5 MA have been completed and additional heating experiments by means of ICRH and NBI are now in process. With ICRH powers up to 7 MW, the global energy confinement time tau/sub E/ is observed to deteriorate with increasing heating power. NBI experiments are at a more preliminary stage, but also show deterioration in tau/sub E/. Detailed studies of confinement time scaling in ohmically heated discharges show a strong dependence of plasma size, tau/sub E/ proportional to R/sup 1.7/a/sup 1.3/, but a much weaker dependence on q and n/sub e/ than seen in smaller experiments. Boundary phenomena have been studied from early 1984. Data on the impurity coverage of limiters and wall have been collected during three successive experimental campaigns. Substantial amounts of wall material have consistently been found on the limiters and a large inventory of hydrogen isotopes concentrated on the colder edges. The wall in the shadow of protective elements shows non-uniform erosion. Langmuir probe measurements of edge plasma parameters have been taken in OH, RF and NB discharges. Additional heating leads generally to a temperature increase of the scrape-off layer. Model calculations using data from these diagnostics seem to produce a consistent picture of impurity production in the scrape-off layer which agrees reasonably well with spectroscopic observations.

  9. Bulk Rashba Semiconductors and Related Quantum Phenomena.

    Science.gov (United States)

    Bahramy, Mohammad Saeed; Ogawa, Naoki

    2017-03-29

    Bithmuth tellurohalides BiTeX (X = Cl, Br and I) are model examples of bulk Rashba semiconductors, exhibiting a giant Rashba-type spin splitting among their both valence and conduction bands. Extensive spectroscopic and transport experiments combined with the state-of-the-art first-principles calculations have revealed many unique quantum phenomena emerging from the bulk Rashba effect in these systems. The novel features such as the exotic inter- and intra-band optical transitions, enhanced magneto-optical response, divergent orbital dia-/para-magnetic susceptibility and helical spin textures with a nontrivial Berry's phase in the momentum space are among the salient discoveries, all arising from this effect. Also, it is theoretically proposed and indications have been experimentally reported that bulk Rashba semiconductors such as BiTeI have the capability of becoming a topological insulator under the application of a hydrostatic pressure. Here, we overview these studies and show that BiTeX are an ideal platform to explore the next aspects of quantum matter, which could ultimately be utilized to create spintronic devices with novel functionalities.

  10. Phantom black holes and critical phenomena

    CERN Document Server

    Azreg-Aïnou, Mustapha; Rodrigues, Manuel E

    2014-01-01

    We consider the two classes cosh and sinh of normal and phantom black holes of Einstein-Maxwell-Dilaton theory. Leaving aside the normal Reissner-Nordstr\\"om black hole, it is shown that only some phantom black holes of both classes exhibit critical phenomena. The two classes share a nonextremality, but special, critical point where the transition is continuous. This point yields a classification scheme for critical points. It is concluded that the two unstable and stable phases coexist on one side of the criticality state and disappear on the other side, that is, there is no configuration where only one phase exists. The sinh class has an extremality critical point where the entropy diverges. The transition from extremality to nonextremality with the charge held constant is accompanied by a loss of mass and an increase in the temperature. A special case of this transition is when the hole is isolated (microcanonical ensemble), it will evolve by emission of energy, which results in a decrease of its mass, to ...

  11. Qualitative Methodology in Analyzing Educational Phenomena

    Directory of Open Access Journals (Sweden)

    Antonio SANDU

    2010-12-01

    Full Text Available Semiological analysis of educational phenomena allow researchers access to a multidimensional universe of meanings that is represented by the school, not so much seen as an institution, but as a vector of social action through educational strategies. We consider education as a multidimensional phenomenon since its analysis allows the researcher to explore a variety of research hypotheses of different paradigmatic perspectives that converge in an educational finality. According to the author Simona Branc one of the most appropriate methods used in qualitative data analysis is Grounded Theory; this one assumes a systematic process of generating concepts and theories based on the data collected. Specialised literature defines Grounded Theory as an inductive approach that starts with general observations and during the analytical process creates conceptual categories that explain the theme explored. Research insist on the role of the sociologic theory of managing the research data and for providing ways of conceptualizing the descriptions and explanations.Qualitative content analysis is based on the constructivist paradigm (constructionist in the restricted sense that we used previously. It aims to create an “understanding of the latent meanings of the analyzed messages”. Quantitative content analysis involves a process of encoding and statistical analysis of data extracted from the content of the paper in the form of extractions like: frequencies, contingency analysis, etc

  12. Chemically Tunable Transport Phenomena of Functionalized Graphene

    Science.gov (United States)

    Leconte, Nicolas; Lherbier, Aurélien; Varchon, Francois; Charlier, Jean-Christophe; Palacios, Juan Jose; Soriano, David; Ordejon, Pablo; Roche, Stephan

    2012-02-01

    We present an ab initio multiscale study and quantum transport simulations using the Kubo formalism [1] of chemically modified graphene based materials, whose properties are tuned by changing the density and nature of grafted molecular units. Depending on the nature of the introduced molecular bonding different conduction mechanism are obtained, including transition from weak to strong Anderson localization [2,3], as well as spin-dependent phenomena [4] and magnetoresistive fingerprints [5]. [4pt] References: [1] H. Ishii, F. Triozon, N. Kobayashi, K. Hirose, and S. Roche, C. R. Physique 10, 283 (2009) [2] N. Leconte, J. Moser, P. Ordejon, H. Tao, A. Lherbier, A. Bachtold, F. Alsina, C.M. Sotomayor Torres, J.-C. Charlier, and S. Roche, ACS Nano 4, 7, 4033-4038 (2010) [3] N. Leconte, A. Lherbier, F. Varchon, P. Ordejon, S. Roche, and J.-C. Charlier (accepted in PRB) [4] N. Leconte, D. Soriano, S. Roche, P. Ordejon, J.-C. Charlier, and J.J. Palacios, ACS Nano 5, 5, 3987-3992 (2011) [5] D. Soriano, N. Leconte, P. Ordejon, J.-C. Charlier, J.J. Palacios, and S. Roche, Phys. Rev. Lett. 107, 016602 (2011)

  13. Fingering phenomena during grain-grain displacement

    Science.gov (United States)

    Mello, Nathália M. P.; Paiva, Humberto A.; Combe, G.; Atman, A. P. F.

    2016-05-01

    Spontaneous formation of fingered patterns during the displacement of dense granular assemblies was experimentally reported few years ago, in a radial Hele-Shaw cell. Here, by means of discrete element simulations, we have recovered the experimental findings and extended the original study to explore the control parameters space. In particular, using assemblies of grains with different geometries (monodisperse, bidisperse, or polydisperse), we measured the macroscopic stress tensor in the samples in order to confirm some conjectures proposed in analogy with Saffman-Taylor viscous fingering phenomena for immiscible fluids. Considering an axial setup which allows to control the discharge of grains and to follow the trajectory and the pressure gradient along the displacing interface, we have applied the Darcy law for laminar flow in fluids in order to measure an "effective viscosity" for each assembly combination, in an attempt to mimic variation of the viscosity ratio between the injected/displaced fluids in the Saffman-Taylor experiment. The results corroborate the analogy with the viscous fluids displacement, with the bidisperse assembly corresponding to the less viscous geometry. But, differently to fluid case, granular fingers only develop for a specific combination of displaced/injected geometries, and we have demonstrated that it is always related with the formation of a force chain network along the finger direction.

  14. Two-Stage Modelling Of Random Phenomena

    Science.gov (United States)

    Barańska, Anna

    2015-12-01

    The main objective of this publication was to present a two-stage algorithm of modelling random phenomena, based on multidimensional function modelling, on the example of modelling the real estate market for the purpose of real estate valuation and estimation of model parameters of foundations vertical displacements. The first stage of the presented algorithm includes a selection of a suitable form of the function model. In the classical algorithms, based on function modelling, prediction of the dependent variable is its value obtained directly from the model. The better the model reflects a relationship between the independent variables and their effect on the dependent variable, the more reliable is the model value. In this paper, an algorithm has been proposed which comprises adjustment of the value obtained from the model with a random correction determined from the residuals of the model for these cases which, in a separate analysis, were considered to be the most similar to the object for which we want to model the dependent variable. The effect of applying the developed quantitative procedures for calculating the corrections and qualitative methods to assess the similarity on the final outcome of the prediction and its accuracy, was examined by statistical methods, mainly using appropriate parametric tests of significance. The idea of the presented algorithm has been designed so as to approximate the value of the dependent variable of the studied phenomenon to its value in reality and, at the same time, to have it "smoothed out" by a well fitted modelling function.

  15. Natural phenomena hazards, Hanford Site, south central Washington

    Energy Technology Data Exchange (ETDEWEB)

    Tallman, A.M.

    1996-04-16

    This document presents the natural phenomena hazard (NPH) loads for use in implementing DOE Order 5480.28, Natural Phenomena Hazards Mitigation, at the Hanford Site in south-central Washington State. The purpose of this document is twofold: (1) summarize the NPH that are important to the design and evaluation of structures, systems, and components at the Hanford Site; (2) develop the appropriate natural phenomena loads for use in the implementation of DOE Order 5480.28. The supporting standards, DOE-STD-1020-94, Natural Phenomena Hazards Design and Evaluation Criteria for Department of Energy Facilities (DOE 1994a); DOE-STD-1022-94, Natural Phenomena Hazards Site Characteristics Criteria (DOE 1994b); and DOE-STD-1023-95, Natural Phenomena Hazards Assessment Criteria (DOE 1995) are the basis for developing the NPH loads.

  16. Temporal Variations in Jupiter's Atmosphere

    Science.gov (United States)

    Simon-Miller, Amy A.; Chanover, N. J.; Yanamandra-Fisher, P.; Hammel, H. B.; dePater, I.; Noll, K.; Wong, M.; Clarke, J.; Sanchez-Levega, A.; Orton, G. S.; Gonzaga, S.

    2009-01-01

    In recent years, Jupiter has undergone many atmospheric changes from storms turning red to global. cloud upheavals, and most recently, a cornet or asteroid impact. Yet, on top of these seemingly random changes events there are also periodic phenomena, analogous to observed Earth and Saturn atmospheric oscillations. We will present 15 years of Hubble data, from 1994 to 2009, to show how the equatorial tropospheric cloud deck and winds have varied over that time, focusing on the F953N, F41 ON and F255W filters. These filters give leverage on wind speeds plus cloud opacity, cloud height and tropospheric haze thickness, and stratospheric haze, respectively. The wind data consistently show a periodic oscillation near 7-8 S latitude. We will discuss the potential for variations with longitude and cloud height, within the calibration limits of those filters. Finally, we will discuss the role that large atmospheric events, such as the impacts in 1994 and 2009, and the global upheaval of 2007, have on temporal studies, This work was supported by a grant from the NASA Planetary Atmospheres Program. HST observational support was provided by NASA through grants from Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under contract NAS5-26555.

  17. Classification of debris flow phenomena in the Faroe Islands

    DEFF Research Database (Denmark)

    Dahl, Mads-Peter Jakob; E. Mortensen, Lis; Jensen, Niels H.

    2012-01-01

    Landslides and debris flow phenomena in particular constitute a threat to human activities in the Faroe Islands. As a contribution to ongoing landslide risk management research, this paper proposes a classification scheme for debris flow phenomena in the Faroe Islands. The scheme, produced through...... with international landslide classification systems, significantly increases the knowledge of debris flow phenomena and promotes a consistent terminology of these within the Faroe Islands....

  18. MODELS FOR THE COUNTER-GRADIENT TRANSPORT PHENOMENA

    Institute of Scientific and Technical Information of China (English)

    蒋剑波; 卢志明; 刘晓明; 刘宇陆

    2001-01-01

    The counter gradient transport phenomena on momentum, energy and passive scalar in turbulent flows were studied by use of the single response function for TSDIA. As a result, models that can describe qualitatively the phenomena are obtained. Then the results are simplified by use of the inertial range theory, and the results for lower degrees agree with results of predecessor. Finally the counter gradient-transport phenomena in channel flow and circular wake flow are analyzed.

  19. Enforced Development Of The Earth's Atmosphere

    CERN Document Server

    Iudin, M

    2010-01-01

    We review some basic issues of the life-prescribed development of the Earth's system and the Earth's atmosphere and discourse the unity of Earth's type of life in physical and transcendental divisions. In physical division, we exemplify and substantiate the origin of atmospheric phenomena in the metabolic pathways acquired by the Earth's life forms. We are especially concerned with emergence of pro-life superficial environments under elaboration of the energy transformations. Analysis of the coupling phenomena of elaborated ozone-oxygen transformation and Arctic bromine explosion is provided. Sensing is a foundation of life and the Earth's life. We offer our explanation of human-like perception, reasoning and creativity. We suggest a number of propositions about association of transcendental and physical divisions and the purpose of existence. The study relates to the tradition of natural philosophy which it follows. The paper is suitable for the popular reading.

  20. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2009-11-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  1. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2010-03-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

  2. Emergent phenomena in manganites under spatial confinement

    Institute of Scientific and Technical Information of China (English)

    Shen Jian; T.Z.Ward; L.F.Yin

    2013-01-01

    It is becoming increasingly clear that the exotic properties displayed by correlated electronic materials such as high-Tc superconductivity in cuprates,colossal magnetoresistance (CMR) in manganites,and heavy-fermion compounds are intimately related to the coexistence of competing nearly degenerate states which couple simultaneously active degrees of freedom—charge,lattice,orbital,and spin states.The striking phenomena associated with these materials are due in a large part to spatial electronic inhomogeneities,or electronic phase separation (EPS).In many of these hard materials,the functionality is a result of the soft electronic component that leads to self-organization.In this paper,we review our recent work on a novel spatial confinement technique that has led to some fascinating new discoveries about the role of EPS in manganites.Using lithographic techniques to confine manganite thin films to length scales of the EPS domains that reside within them,it is possible to simultaneously probe EPS domains with different electronic states.This method allows for a much more complete view of the phases residing in a material and gives vital information on phase formation,movement,and fluctuation.Pushing this trend to its limit,we propose to control the formation process of the EPS using external local fields,which include magnetic exchange field,strain field,and electric field.We term the ability to pattern EPS “electronic nanofabrication.” This method allows us to control the global physical properties of the system at a very fundamental level,and greatly enhances the potential for realizing true oxide electronics.

  3. Transport phenomena in disordered interacting electron systems

    Science.gov (United States)

    Michaeli, Karen

    We develop a user friendly scheme based on the quantum kinetic equation for studying electric and thermal transport phenomena in the presence of interactions and disorder. We demonstrate that this scheme is suitable for both a systematic perturbative calculation as well as a general analysis. The work was motivated by the growing number of experiments of thermal and thermoelectric transport, and the absence of adequate theoretical tools for studying them. In particular, for thermal transport, the widely used Kubo formula is rather cumbersome. In this thesis, we present a systematic derivation of the quantum kinetic approach which we believe can be a good alternative to the Kubo formula. One main advantage of the kinetic approach is that it provides us with an intuitive picture for both electric and thermal transport. The strength of our scheme is in its generality that allow us to apply it for different kinds of interactions. We study the effect of the superconducting fluctuations on the Hall and Nernst effects. We show that the strong Nernst effect observed recently in amorphous superconducting films far above the critical temperature is caused by the fluctuations of the superconducting order parameter. We demonstrate that in the limit T → 0 the contribution of the magnetization ensures the vanishing of the Nernst signal in accordance with the third law of thermodynamics. We obtained a striking agreement between our theoretical calculations and the experimental data in a broad region of temperatures and magnetic fields. In addition, we present the calculation of the Hall conductivity in the vicinity of the superconducting transition driven by a magnetic field. We discuss the peculiar feature of both the Hall coefficient and Nernst signal anticipated near the quantum phase transition.

  4. Association of Taiwan's October rainfall patterns with large-scale oceanic and atmospheric phenomena

    Science.gov (United States)

    Kuo, Yi-Chun; Lee, Ming-An; Lu, Mong-Ming

    2016-11-01

    The variability of the amount of October rainfall in Taiwan is the highest among all seasons. The October rainfall in Taiwan is attributable to interactions between the northeasterly monsoon and typhoons and their interaction with Taiwan's Central Mountain Range. This study applied long-term gridded rainfall data for defining the major rainfall pattern for October in Taiwan. The empirical orthogonal function Model 1 (80%) of the October rainfall and El Niño Southern Oscillation (ENSO) index exhibited a significant out-of-phase coherence in a 2-4 year period band. This is because an easterly flow on the northern edge of an anomalous low-level cyclonic circulation over the South China Sea during a La Niña developing stage increased the occurrence of an autumn cold front and enhanced the northeasterly monsoon toward northern Taiwan. In addition, a southerly flow on the eastern edge of the anomalous cyclone increased the moisture transport from the tropical Pacific toward Taiwan. The warmer sea surface temperature in the South China Sea, Kuroshio, and the subtropical western Pacific, which may have been induced by an ENSO warm phase peak in the preceding winter, promoted the formation of the anomalous low-level cyclonic circulation.

  5. Mathematical models of non-linear phenomena, processes and systems: from molecular scale to planetary atmosphere

    CERN Document Server

    2013-01-01

    This book consists of twenty seven chapters, which can be divided into three large categories: articles with the focus on the mathematical treatment of non-linear problems, including the methodologies, algorithms and properties of analytical and numerical solutions to particular non-linear problems; theoretical and computational studies dedicated to the physics and chemistry of non-linear micro-and nano-scale systems, including molecular clusters, nano-particles and nano-composites; and, papers focused on non-linear processes in medico-biological systems, including mathematical models of ferments, amino acids, blood fluids and polynucleic chains.

  6. Association of Taiwan’s Rainfall Patterns with Large-Scale Oceanic and Atmospheric Phenomena

    Directory of Open Access Journals (Sweden)

    Yi-Chun Kuo

    2016-01-01

    Full Text Available A 50-year (1960–2009 monthly rainfall gridded dataset produced by the Taiwan Climate Change Projection and Information Platform Project was presented in this study. The gridded data (5 × 5 km displayed influence of topography on spatial variability of rainfall, and the results of the empirical orthogonal functions (EOFs analysis revealed the patterns associated with the large-scale sea surface temperature variability over Pacific. The first mode (65% revealed the annual peaks of large rainfall in the southwestern mountainous area, which is associated with southwest monsoons and typhoons during summertime. The second temporal EOF mode (16% revealed the rainfall variance associated with the monsoon and its interaction with the slopes of the mountain range. This pattern is the major contributor to spatial variance of rainfall in Taiwan, as indicated by the first mode (40% of spatial variance EOF analysis. The second temporal EOF mode correlated with the El Niño Southern Oscillation (ENSO. In particular, during the autumn of the La Niña years following the strong El Niño years, the time-varying amplitude was substantially greater than that of normal years. The third temporal EOF mode (7% revealed a north-south out-of-phase rainfall pattern, the slowly evolving variations of which were in phase with the Pacific Decadal Oscillation. Because of Taiwan’s geographic location and the effect of local terrestrial structures, climate variability related to ENSO differed markedly from other regions in East Asia.

  7. Observations of quasi-periodic phenomena associated with a large blowout solar jet

    OpenAIRE

    Morton, Richard; Srivastava, Abhishek; Erdélyi, Robert

    2012-01-01

    Aims: A variety of periodic phenomena have been observed in conjunction with large solar jets. We aim to find further evidence for (quasi-)periodic behaviour in solar jets and determine what the periodic behaviour can tell us about the excitation mechanism and formation process of the large solar jet. \\ud \\ud Methods: Using the 304 Å (He-II), 171 Å (Fe IX), 193 Å (Fe XII/XXIV) and 131 Å (Fe VIII/XXI) filters onboard the Solar Dynamic Observatory (SDO) Atmospheric Imaging Assembly (AIA), we in...

  8. Light-induced phenomena in one-component gas: The transport phenomena

    Science.gov (United States)

    Chermyaninov, I. V.; Chernyak, V. G.

    2016-09-01

    The article presents the theory of transport processes in a one-component gas located in the capillary under the action of resonant laser radiation and the temperature and pressure gradients. The expressions for the kinetic coefficients determining heat and mass transport in the gas are obtained on the basis of the modified Boltzmann equations for the excited and unexcited particles. The Onsager reciprocal relations for cross kinetic coefficients are proven for all Knudsen numbers and for any law interaction of gas particles with each other and boundary surface. Light-induced phenomena associated with the possible non-equilibrium stationary states of system are analyzed.

  9. Conceptual Framework to Enable Early Warning of Relevant Phenomena (Emerging Phenomena and Big Data)

    Energy Technology Data Exchange (ETDEWEB)

    Schlicher, Bob G [ORNL; Abercrombie, Robert K [ORNL; Hively, Lee M [ORNL

    2013-01-01

    Graphs are commonly used to represent natural and man-made dynamic systems such as food webs, economic and social networks, gene regulation, and the internet. We describe a conceptual framework to enable early warning of relevant phenomena that is based on an artificial time-based, evolving network graph that can give rise to one or more recognizable structures. We propose to quantify the dynamics using the method of delays through Takens Theorem to produce another graph we call the Phase Graph. The Phase Graph enables us to quantify changes of the system that form a topology in phase space. Our proposed method is unique because it is based on dynamic system analysis that incorporates Takens Theorem, Graph Theory, and Franzosi-Pettini (F-P) theorem about topology and phase transitions. The F-P Theorem states that the necessary condition for phase transition is a change in the topology. By detecting a change in the topology that we represent as a set of M-order Phase Graphs, we conclude a corresponding change in the phase of the system. The onset of this phase change enables early warning of emerging relevant phenomena.

  10. Individualization of the anisotropic phenomena of the imbalanced Nature

    Science.gov (United States)

    Shlafman, L. M.; Kontar, V. A.

    2013-05-01

    What is an individual phenomenon of Nature? Where are the boundaries? Why it is considered as an individual phenomenon? etc. People cannot directly detect the "something isotropic." Sometimes we notice that there is a "black box." But on closer inspection, especially with new methods, the "black box" began to lighten. It seems that his "blackness" is the result of imperfect human sensors and interpretations, but not a phenomenon of Nature. Really people can identify only the anisotropic phenomena of Nature, but with the significant errors. Let's take a look at our home planet Earth. Where are the borders of our planet? It is may seem as the very simple question. People walk on the land and swim on the seas. This is the border on the surface of land and water. But what is about the dust? The dust is a part of the land, which is in the air. Weight of dust is very small compared to the weight of the planet. But it is the dust has formed valleys. Dust can rise very high above the planet's surface and even fly into the space. A similar situation is with the water. The bulk of the liquid water is in surface and underground waters. Water vapor is in the atmosphere. Atmospheric water is much less than on the earth and under the earth. But atmospheric water plays a huge role in the world and even extends into the space. Without a full accounting of dust and water impossible correctly describe the planet. But with considering the dust and water the planet is not solid-liquid ball. It is like "fuzzy blowball" with the boundaries that go to infinity. This "fuzziness" refers to gravity. The gravitational field does not end in the Lagrange points. This "fuzziness" illustrated by the electro-magnetic fields, etc. Our planet can be seen as a multidimensional anisotropic phenomenon of Nature. The anisotropy precisely is, and therefore is the gradient and movement. This phenomenon is clearly imbalanced because nothing ever repeats itself exactly, etc. The borders of any anisotropic

  11. Seepage phenomena on Mars at subzero temperature

    Science.gov (United States)

    Kereszturi, Akos; Möhlmann, Diedrich; Berczi, Szaniszlo; Ganti, Tibor; Horvath, Andras; Kuti, Adrienn; Pocs, Tamas; Sik, Andras; Szathmary, Eors

    At the southern hemisphere of Mars seasonal slope structures emanating from Dark Dune Spots are visible on MGS MOC, and MRO HiRISE images. Based on their analysis two groups of streaks could be identified: diffuse and fan shaped ones forming in an earlier phase of local spring, probably by CO2 gas jets, and confined streaks forming only on steep slopes during a later seasonal phase. The dark color of the streaks may arise from the dark color of the dune grains where surface frost disappeared above them, or caused by the phase change of the water ice to liquid-like water, or even it may be influenced by the solutes of salts in the undercooled interfacial water The second group's morphology (meandering style, ponds at their end), morphometry, and related theoretical modelling suggest they may form by undercooled water that remains in liquid phase in a thin layer around solid grains. We analyzed sequence of images, temperature and topographic data of Russel (54S 12E), Richardson (72S 180E) and an unnamed crater (68S 2E) during southern spring. The dark streaks here show slow motion, with an average speed of meter/day, when the maximal daytime temperature is between 190 and 220 K. Based on thermophysical considerations a thin layer of interfacial water is inevitable on mineral surfaces under the present conditions of Mars. With 10 precipitable micrometer of atmospheric water vapor, liquid phase can be present down about 190 K. Under such conditions dark streaks may form by the movement of grains lubricatred by interfacial water. This possibility have various consequences on chemical, mechanical or even possible astrobiological processes on Mars. Acknowledgment: This work was supported by the ESA ECS-project No. 98004 and the Pro Renovanda Cultura Hungariae Foundation.

  12. Separation phenomena in Liquids and Gases

    Energy Technology Data Exchange (ETDEWEB)

    Louvet, P.; Dr 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. Electron impact phenomena and the properties of gaseous ions

    CERN Document Server

    Field, F H; Massey, H S W; Brueckner, Keith A

    1970-01-01

    Electron Impact Phenomena and the Properties of Gaseous Ions, Revised Edition deals with data pertaining to electron impact and to molecular gaseous ionic phenomena. This book discusses electron impact phenomena in gases at low pressure that involve low-energy electrons, which result in ion formation. The text also describes the use of mass spectrometers in electron impact studies and the degree of accuracy obtained when measuring electron impact energies. This book also reviews relatively low speed electrons and the transitions that result in the ionization of the atomic system. This text the

  14. Modeling of evaporation and oxidation phenomena in plasma spraying of metal powders

    Science.gov (United States)

    Zhang, Hanwei

    Plasma spraying of metals in air is usually accompanied by evaporation and oxidation of the sprayed material. Optimization of the spraying process must ensure that the particles are fully molten during their short residence time in the plasma jet and prior to hitting the substrate, but not overheated to minimize evaporation losses. In atmospheric plasma spraying (ASP), it is also clearly desirable to be able to control the extent of oxide formation. The objective of this work to develop an overall mathematical model of the oxidization and volatilization phenomena involved in the plasma-spraying of metallic particles in air atmosphere. Four models were developed to simulate the following aspects of the atmospheric plasma spraying (APS) process: (a) the particle trajectories and the velocity and temperature profiles in an Ar-H 2 plasma jet, (b) the heat and mass transfer between particles and plasma jet, (c) the interaction between the evaporation and oxidation phenomena, and (d) the oxidation of liquid metal droplets. The resulting overall model was generated by adapting the computational fluid dynamics code FIDAP and was validated by experimental measurements carried out at the collaborating plasma laboratory of the University of Limoges. The thesis also examined the environmental implications of the oxidization and volatilization phenomena in the plasma spraying of metals. The modeling results showed that the combination of the standard k-s model of turbulence and the Boussinesq eddy-viscosity model provided a more accurate prediction of plasma gas behavior. The estimated NOx generation levels from APS were lower than the U.S.E.P.A. emission standard. Either enhanced evaporation or oxidation can occur on the surface of the metal particles and the relative extent is determined by the process parameters. Comparatively, the particle size has the greatest impact on both evaporation and oxidation. The extent of particle oxidation depends principally on gas

  15. Explaining the Prevalence, Scaling and Variance of Urban Phenomena

    CERN Document Server

    Gomez-Lievano, Andres; Hausmann, Ricardo

    2016-01-01

    The prevalence of many urban phenomena changes systematically with population size. We propose a theory that unifies models of economic complexity and cultural evolution to derive urban scaling. The theory accounts for the difference in scaling exponents and average prevalence across phenomena, as well as the difference in the variance within phenomena across cities of similar size. The central ideas are that a number of necessary complementary factors must be simultaneously present for a phenomenon to occur, and that the diversity of factors is logarithmically related to population size. The model reveals that phenomena that require more factors will be less prevalent, scale more superlinearly and show larger variance across cities of similar size. The theory applies to data on education, employment, innovation, disease and crime, and it entails the ability to predict the prevalence of a phenomenon across cities, given information about the prevalence in a single city.

  16. Nanoelectronics: Thermoelectric Phenomena in «Bottom-Up» Approach

    Directory of Open Access Journals (Sweden)

    Yu.A. Kruglyak

    2014-04-01

    Full Text Available Thermoelectric phenomena of Seebeck and Peltier, quality indicators and thermoelectric optimization, ballistic and diffusive phonon heat current are discussed in the frame of the «bottom-up» approach of modern nanoelectronics.

  17. INVESTIGATIONS INTO BIOFOULING PHENOMENA IN FINE PORE AERATION DEVICES

    Science.gov (United States)

    Microbiologically-based procedures were used to describe biofouling phenomena on fine pore aeration devices and to determine whether biofilm characteristics could be related to diffuser process performance parameters. Fine pore diffusers were obtained from five municipal wastewa...

  18. Probing Cytological and Reproductive Phenomena by Means of Bryophytes.

    Science.gov (United States)

    Newton, M. E.

    1985-01-01

    Describes procedures (recommended for both secondary and college levels) to study mitosis, Giemsa C-banding, reproductive phenomena (including alternation of generations), and phototropism in mosses and liverworts. (JN)

  19. Atmosphere: Power, Critique, Politics

    DEFF Research Database (Denmark)

    Albertsen, Niels

    2016-01-01

    This paper hans three interrelated parts. First, atmosphere is approached through the concept of power. Atmospheres 'grip' us directly or mediate power indirectly by manipulating moods and evoking emotions. How does atmosphere relate to different conceptions of power? Second, atmospheric powers m...... be critiqued. Which conception of critique can be involved? Third, critiquing atmospheric powers can generate political conflict. How does atmospheric disputes relate to conceptions of politics and the political?...

  20. ldentifying Episodes of Earth Science Phenomena Using a Big-Data Technology

    Science.gov (United States)

    Kuo, Kwo-Sen; Oloso, Amidu; Rushing, John; Lin, Amy; Fekete, Gyorgy; Ramachandran, Rahul; Clune, Thomas; Dunny, Daniel

    2014-01-01

    A significant portion of Earth Science investigations is phenomenon- (or event-) based, such as the studies of Rossby waves, volcano eruptions, tsunamis, mesoscale convective systems, and tropical cyclones. However, except for a few high-impact phenomena, e.g. tropical cyclones, comprehensive records are absent for the occurrences or events of these phenomena. Phenomenon-based studies therefore often focus on a few prominent cases while the lesser ones are overlooked. Without an automated means to gather the events, comprehensive investigation of a phenomenon is at least time-consuming if not impossible. We have constructed a prototype Automated Event Service (AES) system that is used to methodically mine custom-defined events in the reanalysis data sets of atmospheric general circulation models. Our AES will enable researchers to specify their custom, numeric event criteria using a user-friendly web interface to search the reanalysis data sets. Moreover, we have included a social component to enable dynamic formation of collaboration groups for researchers to cooperate on event definitions of common interest and for the analysis of these events. An Earth Science event (ES event) is defined here as an episode of an Earth Science phenomenon (ES phenomenon). A cumulus cloud, a thunderstorm shower, a rogue wave, a tornado, an earthquake, a tsunami, a hurricane, or an El Nino, is each an episode of a named ES phenomenon, and, from the small and insignificant to the large and potent, all are examples of ES events. An ES event has a duration (often finite) and an associated geo-location as a function of time; it's therefore an entity embedded in four-dimensional (4D) spatiotemporal space. Earth Science phenomena with the potential to cause massive economic disruption or loss of life often rivet the attention of researchers. But, broader scientific curiosity also drives the study of phenomena that pose no immediate danger, such as land/sea breezes. Due to Earth System

  1. [Problems of psychiatrization, medicalization and related social phenomena].

    Science.gov (United States)

    Opalić, Petar

    2009-01-01

    The introduction contains definitions of the terms psychiatrization, medicalization, psychotherapeutization and psychologization of the society, i.e. social problems. Different aspects of the above phenomena are analyzed, their origin, relation with the professions they originate from, and, finally, their social significance, i.e. social function. In conclusion, the article points to different possibilities to prevent the above phenomena, undesirable both for the society and the objectives and activities of the professions they originate from.

  2. On Process Modelling Using Physical Oriented And Phenomena Based Principles

    Directory of Open Access Journals (Sweden)

    Mihai Culea

    2000-12-01

    Full Text Available This work presents a modelling framework based on phenomena description of the process. The approach is taken to easy understand and construct process model in heterogeneous possible distributed modelling and simulation environments. A simplified case study of a heat exchanger is considered and Modelica modelling language to check the proposed concept. The partial results are promising and the research effort will be extended in a computer aided modelling environment based on phenomena.

  3. Classification of Transient Phenomena in Distribution System using wavelet Transform

    Science.gov (United States)

    Sedighi, Alireza

    2014-05-01

    An efficient procedure for classification of transient phenomena in distribution systems is proposed in this paper. The proposed method has been applied to classify some transient phenomena such as inrush current, load switching, capacitor switching and single phase to ground fault. The new scheme is based on wavelet transform algorithm. All of the events for feature extraction and test are simulated using Electro Magnetic Transient Program (EMTP). Results show high accuracy of proposed method.

  4. Role of magnetospheric plasma physics for understanding cosmic phenomena

    Science.gov (United States)

    Das, Indra M. L.

    Cosmic phenomena occur in the remote regions of space where in situ observations are not possible. For a proper understanding of these phenomena, laboratory experiments are essential, but in situ observations of magnetospheric plasma provide an even better background to test various hypothesis of cosmic interest. This is because the ionospheric-magnetospheric plasma and the solar wind are the only cosmic plasmas accessible to extensive in situ observations and experiments.

  5. [Non-epileptic motor paroxysmal phenomena in wakefulness in childhood].

    Science.gov (United States)

    Ruggieri, Víctor L; Arberas, Claudia L

    2013-09-06

    Paroxysmal events in childhood are a challenge for pediatric neurologists, given its highly heterogeneous clinical manifestations, often difficult to distinguish between phenomena of epileptic seizure or not. The non-epileptic paroxysmal episodes are neurological phenomena, with motor, sensory symptoms, and/or sensory impairments, with or without involvement of consciousness, epileptic phenomena unrelated, so no electroencephalographic correlative expression between or during episodes. From the clinical point of view can be classified into four groups: motor phenomena, syncope, migraine (and associated conditions) and acute psychiatric symptoms. In this paper we analyze paroxysmal motor phenomena in awake children, dividing them according to their clinical manifestations: extrapyramidal episodes (paroxysmal kinesiogenic, non kinesiogenic and not related to exercise dyskinesias, Dopa responsive dystonia) and similar symptoms of dystonia (Sandifer syndrome); manifestations of startle (hyperekplexia); episodic eye and head movements (benign paroxysmal tonic upward gaze nistagmus deviation); episodic ataxia (familial episodic ataxias, paroxysmal benign vertigo); stereotyped and phenomena of self-gratification; and myoclonic events (benign myoclonus of early infancy). The detection of these syndromes will, in many cases, allow an adequate genetic counseling, initiate a specific treatment and avoid unnecessary additional studies. Molecular studies have demonstrated a real relationship between epileptic and non-epileptic basis of many of these entities and surely the identification of the molecular basis and understanding of the pathophysiological mechanisms in many of them allow us, in the near future will benefit our patients.

  6. Encoding continuous spatial phenomena in GML

    Science.gov (United States)

    de Vries, M. E.; Ledoux, H.

    2009-04-01

    In the discussion about how to model and encode geographic information two meta-models of space exist: the 'object' view and the 'field' view. This difference in conceptual view is also reflected in different data models and encoding formats. Among GIS practitioners, ‘fields' (or ‘coverages') are being used almost exclusively in 2D, while in the geoscience community 3D and higher-dimensional fields are widely used. (Note that the dimensions in oceanographic/atmospheric coverages are not necessarily spatial dimensions, as any parameters (e.g. temperature of the air, or density of water) can be considered a dimension.) While standardisation work in ISO and OGC has led to agreement on how to best encode discrete spatial objects, for the modelling and encoding of continuous ‘fields' there are still a number of open issues. In the presentation we will shortly discuss the current standards related to fields, and look at their shortcomings and potential. In ISO 19123 for example a distinction is made between discrete and continuous coverages, but the difference is not very clear and hard to capture for implementers. As far as encoding is concerned: GML 3.x (ISO 19136) has a discrete coverage data type, but no continuous coverage type. We will then present an alternative solution to model fields, and show how it can be implemented using some parts of GML, but not the ISO/GML coverage type. This alternative data model for fields permits us to represent fields in 2D and 3D, although conceptually it can be easily extended to higher dimensions. Unlike current standards where there is a distinction between discrete and continuous fields/coverages, we argue that a field should always have one - and only one! - value for a given attribute at every location in the spatial domain (be this domain the surface of the Earth, a 3D volume, or even a 4D spatio-temporal hypercube). The principal idea behind the proposed model is that two things are needed to have a coverage: 1. a set

  7. Microbiology and atmospheric processes: research challenges concerning the impact of airborne micro-organisms on the atmosphere and climate

    Directory of Open Access Journals (Sweden)

    C. E. Morris

    2011-01-01

    Full Text Available For the past 200 years, the field of aerobiology has explored the abundance, diversity, survival and transport of micro-organisms in the atmosphere. Micro-organisms have been explored as passive and severely stressed riders of atmospheric transport systems. Recently, an interest in the active roles of these micro-organisms has emerged along with proposals that the atmosphere is a global biome for microbial metabolic activity and perhaps even multiplication. As part of a series of papers on the sources, distribution and roles in atmospheric processes of biological particles in the atmosphere, here we describe the pertinence of questions relating to the potential roles that air-borne micro-organisms might play in meteorological phenomena. For the upcoming era of research on the role of air-borne micro-organisms in meteorological phenomena, one important challenge is to go beyond descriptions of abundance of micro-organisms in the atmosphere toward an understanding of their dynamics in terms of both biological and physico-chemical properties and of the relevant transport processes at different scales. Another challenge is to develop this understanding under contexts pertinent to their potential role in processes related to atmospheric chemistry, the formation of clouds, precipitation and radiative forcing. This will require truly interdisciplinary approaches involving collaborators from the biological and physical sciences, from disciplines as disparate as agronomy, microbial genetics and atmosphere physics, for example.

  8. Exact Solutions for a Higher-Order Nonlinear Schr(o)dinger Equation in Atmospheric Dynamics

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    By giving prior assumptions on the form of the solutions, we succeed to find several exact solutions for a higher-order nonlinear Schrodinger equation derived from one important model in the study of atmospheric and ocean dynamical systems. Our analytical solutions include bright and dark solitary waves, and periodical solutions, which can be used to explain atmospheric phenomena.

  9. PREFACE: Transport phenomena in proton conducting media Transport phenomena in proton conducting media

    Science.gov (United States)

    Eikerling, Michael

    2011-06-01

    Proton transport phenomena are of paramount importance for acid-base chemistry, energy transduction in biological organisms, corrosion processes, and energy conversion in electrochemical systems such as polymer electrolyte fuel cells. The relevance for such a plethora of materials and systems, and the ever-lasting fascination with the highly concerted nature of underlying processes drive research across disciplines in chemistry, biology, physics and chemical engineering. A proton never travels alone. Proton motion is strongly correlated with its environment, usually comprised of an electrolyte and a solid or soft host material. For the transport in nature's most benign proton solvent and shuttle, water that is, insights from ab initio simulations, matured over the last 15 years, have furnished molecular details of the structural diffusion mechanism of protons. Excess proton movement in water consists of sequences of Eigen-Zundel-Eigen transitions, triggered by hydrogen bond breaking and making in the surrounding water network. Nowadays, there is little debate about the validity of this mechanism in water, which bears a stunning resemblance to the basic mechanistic picture put forward by de Grotthuss in 1806. While strong coupling of an excess proton with degrees of freedom of solvent and host materials facilitates proton motion, this coupling also creates negative synergies. In general, proton mobility in biomaterials and electrochemical proton conducting media is highly sensitive to the abundance and structure of the proton solvent. In polymer electrolyte membranes, in which protons are bound to move in nano-sized water-channels, evaporation of water or local membrane dehydration due to electro-osmotic coupling are well-known phenomena that could dramatically diminish proton conductivity. Contributions in this special issue address various vital aspects of the concerted nature of proton motion and they elucidate important structural and dynamic effects of solvent

  10. Diffusion phenomena of cells and biomolecules in microfluidic devices.

    Science.gov (United States)

    Yildiz-Ozturk, Ece; Yesil-Celiktas, Ozlem

    2015-09-01

    Biomicrofluidics is an emerging field at the cross roads of microfluidics and life sciences which requires intensive research efforts in terms of introducing appropriate designs, production techniques, and analysis. The ultimate goal is to deliver innovative and cost-effective microfluidic devices to biotech, biomedical, and pharmaceutical industries. Therefore, creating an in-depth understanding of the transport phenomena of cells and biomolecules becomes vital and concurrently poses significant challenges. The present article outlines the recent advancements in diffusion phenomena of cells and biomolecules by highlighting transport principles from an engineering perspective, cell responses in microfluidic devices with emphases on diffusion- and flow-based microfluidic gradient platforms, macroscopic and microscopic approaches for investigating the diffusion phenomena of biomolecules, microfluidic platforms for the delivery of these molecules, as well as the state of the art in biological applications of mammalian cell responses and diffusion of biomolecules.

  11. Nonlinear Magnetic Phenomena in Highly Polarized Target Materials

    CERN Document Server

    Kiselev, Yu F

    2007-01-01

    The report introduces and surveys nonlinear magnetic phenomena which have been observed at high nuclear polarizations in polarized targets of the SMC and of the COMPASS collaborations at CERN. Some of these phenomena, namely the frequency modulation eect and the distortion of the NMR line shape, promote the development of the polarized target technique. Others, as the spin-spin cross-relaxation between spin subsystems can be used for the development of quantum statistical physics. New findings bear on an electromagnetic noise and the spectrally resolved radiation from LiD with negatively polarized nuclei detected by low temperature bolometers. These nonlinear phenomena need to be taken into account for achieving the ultimate polarizations.

  12. Biomedical Signals and Sensors I Linking Physiological Phenomena and Biosignals

    CERN Document Server

    Kaniusas, Eugenijus

    2012-01-01

    This two-volume set focuses on the interface between physiologic mechanisms and diagnostic human engineering. Today numerous biomedical sensors are commonplace in clinical practice. The registered biosignals reflect mostly vital physiologic phenomena. In order to adequately apply biomedical sensors and reasonably interpret the corresponding biosignals, a proper understanding of the involved physiologic phenomena, their influence on the registered biosignals, and the technology behind the sensors is necessary. The first volume is devoted to the interface between physiologic mechanisms and arising biosignals, whereas the second volume is focussed on the interface between biosignals and biomedical sensors. The physiologic mechanisms behind the biosignals are described from the basic cellular level up to their advanced mutual coordination level during sleep. The arising biosignals are discussed within the scope of vital physiologic phenomena to foster their understanding and comprehensive analysis.

  13. Transport phenomena in Newtonian fluids a concise primer

    CERN Document Server

    Olsson, Per

    2013-01-01

    This short primer provides a concise and tutorial-style introduction to transport phenomena in Newtonian fluids , in particular the transport of mass, energy and momentum.  The reader will find detailed derivations of the transport equations for these phenomena, as well as selected analytical solutions to the transport equations in some simple geometries. After a brief introduction to the basic mathematics used in the text, Chapter 2, which deals with momentum transport, presents a derivation of the Navier-Stokes-Duhem equation describing the basic flow in a Newtonian fluid.  Also provided at

  14. Time in powers of ten natural phenomena and their timescales

    CERN Document Server

    't Hooft, Gerard

    2014-01-01

    In this richly illustrated book, Nobel Laureate Gerard 't Hooft and Theoretical Physicist Stefan Vandoren describe the enormous diversity of natural phenomena that take place at different time scales. In the tradition of the bestseller Powers of Ten , the authors zoom in and out in time, each step with a factor of ten. Starting from one second, time scales are enlarged until processes are reached that take much longer than the age of the universe. After the largest possible eternities, the reader is treated to the shortest and fastest phenomena known. Then the authors increase with powers of t

  15. Feedback Linearization Controller Of The Delta WingRock Phenomena

    Directory of Open Access Journals (Sweden)

    Mohammed Alkandari

    2015-05-01

    Full Text Available This project deals with the control of the wing rock phenomena of a delta wing aircraft. a control schemeis proposed to stabilize the system. The controlleris a feedback linearization controller. It is shown that the proposed control scheme guarantee the asymptotic convergence to zero of all the states of the system. To illustrate the performance of the proposed controller, simulation results are presented and discussed. It is found that the proposed control scheme work well for the wing rock phenomena of a delta wing aircraft.

  16. Interaction and resonance phenomena of multi-soliton

    Institute of Scientific and Technical Information of China (English)

    YANG Hong-juan; SHI Yu-ren; DUAN Wen-shan

    2006-01-01

    As is well known,Korteweg-de Vries equation is a typical one which has planar solitary wave.By considering higher order transverse disturbance to planar solitary waves,we study a Kadomtsev-Petviashvili (KP) equation and find some interesting results.In this letter we investigate the three soliton interaction and their resonance phenomena of KP equation,and theoretically find that the maximum amplitude is 9 times of the initial interacting soliton for three same amplitude solitons.Three arbitrary amplitude soliton interaction of KP equation is also studied by numerical simulation,which can also results in resonance phenomena.

  17. Psychosocial Aspects of Dental Anxiety and Clinical Pain Phenomena

    DEFF Research Database (Denmark)

    Moore, Rod

    This Danish Doctoral Dissertation in the science of Odontology contains 7 chapters: 1) Introduction to a social perspective on dental treatment, anxiety and pain throughout time, 2) research models and methods to study dental anxiety and clinical pain phenomena, 3) the fear of dental treatment...... .. what it is and what it is not and how many have it, 4) clinical pain treatment, psychosocial aspects in relation to anxiety, 4) patients and dentists' roles, pain perception and anxiety, 6) psychosocial aspects of managing anxiety and pain phenomena, and 7) Conclusions and proposals for the future...

  18. Temperature Sensitive Optical Phenomena in Heavy Metal Halide Films.

    Science.gov (United States)

    1979-01-08

    Heavy - metal halides such as Pb!2 and HgI2 exhibit a strongly tempera- ture dependent absorption edge at visible frequencies. The shift in the absorption...AOb9 537 ROCKWELL INTERNATIONAL ANAHEIM CA ELECTRONICS RESEAR—— ETC FIG L u G TEMPERATURE SENSITIVE OPTICAL PHENOMENA IN HEAVY METAL HALIDE F—— ETC (U...PHENOMENA IN HEAVY METAL HALIDE F — ET C( U) ,JAN 79 J D MC*LLEN, D M HEINZ. F S STEARNS DAAK7O— 77—C—01 6 5 UNCLASSIFIED C79 1501 _ _ U SB

  19. Thermionic phenomena the collected works of Irving Langmuir

    CERN Document Server

    Suits, C Guy

    1961-01-01

    Thermionic Phenomena is the third volume of the series entitled The Collected Works of Irving Langmuir. This volume compiles articles written during the 1920's and early 1930's, the period when the science of thermionics is beginning to be of importance. This text is divided into two parts. The first part discusses vacuum pumps, specifically examining the effect of space charge and residual gases on thermionic currents in high vacuum. This part also explains fundamental phenomena in electron tubes having tungsten cathodes and the use of high-power vacuum tubes. The second part of this text loo

  20. Pseudospin-mediated phenomena in photonic graphene (Conference Presentation)

    Science.gov (United States)

    Song, Daohong; Efremedis, Nikos; Chen, Zhigang

    2016-09-01

    "Photonic graphene" has been demonstrated as a useful platform to study fundamental physics such as edge states and topological insulators. Recently, we have demonstrated pseudospin-mediated generation of topological charges in photonic graphene. Due to sublattice degree of freedom, charge flipping is observed as the sublattices are selectively excited. Our experimental results are confirmed by numerical simulation as well as by theoretical analysis of the 2D Dirac-Weyl equations. In this talk, we will discuss such pseudospin-related phenomena due to the sublattice degree of freedom, along with our recent work on related phenomena due to the graphene valley degree of freedom.

  1. Atmospheric composition change: Ecosystems-Atmosphere interactions

    NARCIS (Netherlands)

    Fowler, D.; Pilegaard, K.; Sutton, M.A.; Ambus, P.; Raivonen, M.; Duyzer, J.; Simpson, D.; Fagerli, H.; Fuzzi, S.; Schjoerring, J.K.; Granier, C.; Neftel, A.; Isaksen, I.S.A.; Laj, P.; Maione, M.; Monks, P.S.; Burkhardt, J.; Daemmgen, U.; Neirynck, J.; Personne, E.; Wichink Kruit, R.J.; Butterbach-Bahl, K.; Flechard, C.; Tuovinen, J.P.; Coyle, M.; Gerosa, G.; Loubet, B.; Altimir, N.; Gruenhage, L.; Ammann, C.; Cieslik, S.; Paoletti, E.; Mikkelsen, T.N.; Ro-Poulsen, H.; Cellier, P.; Cape, J.N.; Horvath, L.; Loreto, F.; Niinemets, U.; Palmer, P.I.; Rinne, J.; Misztal, P.; Nemitz, E.; Nilsson, D.; Pryor, S.; Gallagher, M.W.; Vesala, T.; Skiba, U.; Brueggemann, N.; Zechmeister-Boltenstern, S.; Williams, J.; O'Dowd, C.; Facchini, M.C.; Leeuw, de G.; Flossman, A.; Chaumerliac, N.; Erisman, J.W.

    2009-01-01

    Ecosystems and the atmosphere: This review describes the state of understanding the processes involved in the exchange of trace gases and aerosols between the earth's surface and the atmosphere. The gases covered include NO, NO2, HONO, HNO3, NH3, SO2, DMS, Biogenic VOC, O-3, CH4, N2O and particles i

  2. Spent nuclear fuel project detonation phenomena of hydrogen/oxygen in spent fuel containers

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, T.D.

    1996-09-30

    Movement of Spent N Reactor fuels from the Hanford K Basins near the Columbia River to Dry interim storage facility on the Hanford plateau will require repackaging the fuel in the basins into multi-canister overpacks (MCOs), drying of the fuel, transporting the contained fuel, hot conditioning, and finally interim storage. Each of these functions will be accomplished while the fuel is contained in the MCOs by several mechanisms. The principal source of hydrogenand oxygen within the MCOs is residual water from the vacuum drying and hot conditioning operations. This document assesses the detonation phenomena of hydrogen and oxygen in the spent fuel containers. Several process scenarios have been identified that could generate detonation pressures that exceed the nominal 10 atmosphere design limit ofthe MCOS. Only 42 grams of radiolized water are required to establish this condition.

  3. The influence of large-scale climate phenomena on precipitation in the Ordos Basin, China

    Science.gov (United States)

    Zhong, Yu; Lei, Liyuan; Liu, Youcun; Hao, Yonghong; Zou, Chris; Zhan, Hongbin

    2016-09-01

    Large-scale atmospheric circulations significantly affect regional precipitation patterns. However, it is not well known whether and how these phenomena affect regional precipitation distribution in northern China. This paper reported the individual and coupled effects of El Niño-Southern Oscillation (ENSO), Indian summer monsoon (ISM), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) on annual precipitation for the Ordos Basin, an arid and semi-arid basin, currently with major industries of coal, fossil oil, natural gas, and halite in north central China. Our results showed that ENSO and ISM exerted substantial impact on annual precipitation while the impact of PDO and AMO was relatively limited. There were 24 and 15 out of 33 stations showing significant differences (p planning and disaster management for the Ordos Basin.

  4. Atmospheric excitation of the Earth's rotation rate

    Science.gov (United States)

    Merriam, J. B.

    Modern techniques for the determination of the Earth's rotation rate: long-baseline interferometry, satellite laser ranging, and lunar laser ranging, now permit the orientation of the Earth to be determined with an accuracy of 5 cm, which corresponds to about 10-4 sec in Universal Time. This nearly order-of-magnitude improvement over what was available ten years ago makes it feasible to look at variations in the length-of-day on much shorter time-scales. At the same time, the requirements of operational weather forecasting have resulted in more detailed knowledge of the variations of the angular momentum of the atmosphere. The result has been a convincing demonstration over the last several years that virtually all of the random variations in the length-of-day, at periods between a few years and a day, are due to atmospheric variations. Geophysicists and meteorologists have both exploited this discovery. Removal of the atmospheric signal from the length-of-day, results in a data set in which other interesting phenomena of geophysical interest can be studied. Meteorologists have had some success in using the rotation data to deduce the angular momentum of the atmosphere at times in the past when sufficient global coverage was not available to do this directly. Outstanding problems are: the low frequency variations in atmospheric angular momentum, which the passage of time will correct, and the details of the mechanism by which angular momentum is exchanged with the mantle.

  5. Removal of Atmospheric Particles in Poor Visibility Outdoor Images

    Directory of Open Access Journals (Sweden)

    Yaseen Al-Zubaidy

    2013-08-01

    Full Text Available The visibility of a scene is degraded by weather phenomena such as rain drizzle, fog and haze. The degradation of image scene is due the substantial presence of particles in the atmosphere that scatter and absorb light. As the light spreads from object to the observer, the color and intensity is changed by the atmospheric particles. In this research, we suggest new methods to precisely detect airlight and correctly estimate the atmospheric veil from image that captured in bad weather. The result of suggested methods will be used in scattering atmospheric model to remove atmospheric particles namely, rain drizzle, fog and haze from a single image. Therefore a higher visibility image will be produced.

  6. Kuiper Prize Lecture - Escape of atmospheres, ancient and modern

    Energy Technology Data Exchange (ETDEWEB)

    Hunten, D.M. (Arizona Univ., Tucson (USA))

    1990-05-01

    A development history is presented for theories concerning planetary atmosphere gas-escape phenomena, which although firmly grounded in the kinetics of gases achieved truly productive results only after spacecraft remote sensing data for both the earth atmosphere and the planets became widely available. The most significant initial advances, encompassing diffusion-limited flow, nonthermal escape mechanisms, bound nonthermal coronas, and mass fractionation during early blowoff, followed from sounding rocket studies of the earth upper atmosphere, Mariner 5 results on hydrogen near Venus, and the nitrogen isotopic composition discovered by Viking in Mars. Attention has more recently been given to the xenon isotopic patterns in various atmospheres, as well as to the puzzling behavior of the Io atmosphere and plasma torus. 126 refs.

  7. Ground-based Optical Observations of Geophysical Phenomena: Aurora Borealis and Meteors

    Science.gov (United States)

    Samara, Marilia

    2010-10-01

    Advances in low-light level imaging technology have enabled significant improvements in the ground based study of geophysical phenomena. In this talk we focus on two such phenomena that occur in the Earth's ionosphere: aurorae and meteors. Imaging the aurora which is created by the interplay of the Earth's magnetosphere, ionosphere and atmosphere, provides a tool for remote sensing physical processes that are otherwise very difficult to study. By quantifying the intensities, scale sizes and lifetimes of auroral structures, we can gain significant insight into the physics behind the generation of the aurora and the interaction of the magnetosphere with the solar wind. Additionally, the combination of imaging with radars provides complimentary data and therefore more information than either method on its own. Meteor observations are a perfect example of this because the radar can accurately determine only the line-of-sight component of velocity, while imaging provides the direction of motion, the perpendicular velocity and brightness (a proxy for mass), therefore enabling a much more accurate determination of the full velocity vector and mass.

  8. Complex airborne system with combined action on the conditions of risk weather phenomena

    Directory of Open Access Journals (Sweden)

    Niculae MARIN

    2010-06-01

    Full Text Available The study of the weather phenomena is one of the main concerns of scientists. Initially, theresearches in this area were intended to provide military structures new ways of fighting in wars suchas the wars in Korea or Vietnam and then continued with the development of technologies to combatthe phenomena that affect the normal conditions of agriculture, the environment, etc. -extremephenomena- hail, low precipitation regime, etc. Since the last decade of last century also in Romaniathere were a number of initiatives supported through a national program of research in the fightagainst hail and stimulation of precipitation. In this context, INCAS proposed in 2008 a researchproject to implement a complex airborne system, which carry out actions to limit the effects of extremeweather events on crops and objectives of national and strategic interest, on the basis of informationreceived from a system of sensors located on the air platform and intended for measuring the physicalcharacteristics of the atmosphere. Also, as a long-term effect, the action of the complex airbornesystem may lead to the rainfall regulation and control, with all the implications arising from this(avoiding flooding, providing protection from frost of autumn crop, etc.The aerial platform chosen for this research approach is the aircraft for school and training IAR99SOIM, INCAS being the author of its structural design and also holding the patent for IndustrialDesign nr.00081 registered with OSIM. Project acronym : COMAEROPREC.

  9. Atmospheric Pressure Indicator.

    Science.gov (United States)

    Salzsieder, John C.

    1995-01-01

    Discusses observable phenomena related to air pressure. Describes a simple, unobtrusive, semiquantitative device to monitor the changes in air pressure that are associated with altitude, using a soft-drink bottle and a balloon. (JRH)

  10. Electrostatic phenomena in organic semiconductors: fundamentals and implications for photovoltaics

    Science.gov (United States)

    D'Avino, Gabriele; Muccioli, Luca; Castet, Frédéric; Poelking, Carl; Andrienko, Denis; Soos, Zoltán G.; Cornil, Jérôme; Beljonne, David

    2016-11-01

    This review summarizes the current understanding of electrostatic phenomena in ordered and disordered organic semiconductors, outlines numerical schemes developed for quantitative evaluation of electrostatic and induction contributions to ionization potentials and electron affinities of organic molecules in a solid state, and illustrates two applications of these techniques: interpretation of photoelectron spectroscopy of thin films and energetics of heterointerfaces in organic solar cells.

  11. Explosive phenomena in heavily irradiated NaCl

    NARCIS (Netherlands)

    denHartog, HW; Vainshtein, DI; Matthews, GE; Williams, RT

    1997-01-01

    In heavily irradiated NaCl crystals explosive phenomena can be initiated during irradiation or afterwards when samples are heated to temperatures between 100 and 250 degrees C. During irradiation of NaCl Na and Cl-2 precipitates and void structures are produced along with the accumulation of stored

  12. Developing Critical Thinking through the Study of Paranormal Phenomena.

    Science.gov (United States)

    Wesp, Richard; Montgomery, Kathleen

    1998-01-01

    Argues that accounts of paranormal phenomena can serve as an ideal medium in which to encourage students to develop critical-thinking skills. Describes a cooperative-learning approach used to teach critical thinking in a course on paranormal events. Reports that critical-thinking skills increased and that the course received favorable student…

  13. The Effects of Globalization Phenomena on Educational Concepts

    Science.gov (United States)

    Schrottner, Barbara Theresia

    2010-01-01

    It is becoming more and more apparent that globalization processes represent, theoretically as well as practically, a challenge for educational sciences and therefore, it must be addressed within the sphere of education. Accordingly, educational conceptions have to adapt to globalization phenomena and focus more on alternative and innovative…

  14. Synchronization Phenomena in an Array of Population Dynamic Systems

    DEFF Research Database (Denmark)

    Postnov, D.E.; Balanov, A.G.; Mosekilde, Erik

    1998-01-01

    The paper applies continuation methods to examine synchronization phenomena that can arise in a cascaded system of population dynamic models. The individual model describes a bacterial population interacting with a population of viruses that attack the cells. Coupling between the subsystems...

  15. A Curriculum Framework Based on Archetypal Phenomena and Technologies.

    Science.gov (United States)

    Zubrowski, Bernie

    2002-01-01

    Presents an alternative paradigm of curriculum development based on the theory of situated cognition. This approach starts with context rather than concept, gives greater weight to students' interpretative frameworks, and provides for a more holistic development. Presents a grade 1-8 framework that uses archetypal phenomena and technologies as the…

  16. Electrostatic phenomena in organic semiconductors: fundamentals and implications for photovoltaics.

    Science.gov (United States)

    D'Avino, Gabriele; Muccioli, Luca; Castet, Frédéric; Poelking, Carl; Andrienko, Denis; Soos, Zoltán G; Cornil, Jérôme; Beljonne, David

    2016-11-01

    This review summarizes the current understanding of electrostatic phenomena in ordered and disordered organic semiconductors, outlines numerical schemes developed for quantitative evaluation of electrostatic and induction contributions to ionization potentials and electron affinities of organic molecules in a solid state, and illustrates two applications of these techniques: interpretation of photoelectron spectroscopy of thin films and energetics of heterointerfaces in organic solar cells.

  17. Undergraduate Laboratory Experiment Modules for Probing Gold Nanoparticle Interfacial Phenomena

    Science.gov (United States)

    Karunanayake, Akila G.; Gunatilake, Sameera R.; Ameer, Fathima S.; Gadogbe, Manuel; Smith, Laura; Mlsna, Deb; Zhang, Dongmao

    2015-01-01

    Three gold-nanoparticle (AuNP) undergraduate experiment modules that are focused on nanoparticles interfacial phenomena have been developed. Modules 1 and 2 explore the synthesis and characterization of AuNPs of different sizes but with the same total gold mass. These experiments enable students to determine how particle size affects the AuNP…

  18. On some phenomena concerning pregnancy and parturition of the Cetacea

    NARCIS (Netherlands)

    Slijper, E.J.

    1949-01-01

    1. A review is given of some phenomena concerning pregnancy and parturition of the Cetacea, depending on data in literature and on observations made in Antarctic Blue and Fin Whales on board the f.f. “Willem Barendsz” (1946—1947). 2. In Mystacoceti the frequency of twins appears to be less than in m

  19. Extreme wave phenomena in down-stream running modulated waves

    NARCIS (Netherlands)

    Andonowati,; Karjanto, N.; Groesen, van E.

    2006-01-01

    Modulational, Benjamin-Feir, instability is studied for the down-stream evolution of surface gravity waves. An explicit solution, the soliton on finite background, of the NLS equation in physical space is used to study various phenomena in detail. It is shown that for sufficiently long modulation le

  20. Coupled electric and transport phenomena in porous media

    NARCIS (Netherlands)

    Li, Shuai

    2014-01-01

    The coupled electrical and transport properties of clay-containing porous media are the topics of interest in this study. Both experimental and numerical (pore network modeling) techniques are employed to gain insight into the macro-scale interaction between electrical and solute transport phenomena

  1. THE EFFECT OF MEMORY TERMS IN DIFFUSION PHENOMENA

    Institute of Scientific and Technical Information of China (English)

    A. Araújo; J.A. Ferreira; P. Oliveira

    2006-01-01

    In this paper the effect of integral memory terms in the behavior of diffusion phenomena is studied. The energy functional associated with different models is analyzed and stability inequalities are established. Approximation methods for the computation of the solution of the integro-differential equations are constructed. Numerical results are included.

  2. Nuclear phenomena in low-energy nuclear reaction research.

    Science.gov (United States)

    Krivit, Steven B

    2013-09-01

    This is a comment on Storms E (2010) Status of Cold Fusion, Naturwissenschaften 97:861-881. This comment provides the following remarks to other nuclear phenomena observed in low-energy nuclear reactions aside from helium-4 make significant contributions to the overall energy balance; and normal hydrogen, not just heavy hydrogen, produces excess heat.

  3. Wave propagation phenomena in metamaterials for retrieving of effective parameters

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Ha, S.;

    2011-01-01

    In the talk we give an overview of the developed restoration procedures and discuss their pros and cons in connection of assigning effective parameters (EP) to metamaterials (MMs). There are plenty of notorious physical phenomena preserving the unambiguous retrieving of EP, like strong coupling...

  4. Condensation phenomena and frost problems in the air heat recuperators

    Directory of Open Access Journals (Sweden)

    Adamski Mariusz

    2014-01-01

    Full Text Available Investigation results of condensation phenomena and frost problems in the ventilation heat recuperators are presented. The experiments have been conducted for typical value of indoor temperature 20°C and a large range of humidity values from 20 to 75% and more of an exhausted air. The heat exchanger worked in the real conditions of the winter climate in Bialystok.

  5. A generalized Cauchy process and its application to relaxation phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Lim, S C [Faculty of Engineering, Multimedia University, 63100 Cyberjaya, Selangor (Malaysia); Li Ming [School of Information Science and Technology, East China Normal University, Shanghai 200026 (China)

    2006-03-24

    We study some of the basic properties of a generalized Cauchy process indexed by two parameters. The application of the Lamperti transformation to the generalized Cauchy process leads to a self-similar process which preserves the long-range dependence. The asymptotic properties of spectral density of the process are derived. Possible application of this process to model relaxation phenomena is considered.

  6. Consolidation mechanisms and interfacial phenomena in thermoplastic powder impregnated composites

    OpenAIRE

    1995-01-01

    Thermoplastic powder impregnation of continuous reinforcement filaments is studied in this work, focusing on impregnation mechanisms and interfacial phenomena. Various existing techniques to mingle powdered resins to continuous filaments are reviewed; a powder impregnation line designed at the Laboratoire de Technologie des Composites et Polymères (LTC) is presented. Two important types of powder coated towpregs are addressed: FIT bundles (Fibre...

  7. Fundamental phenomena of quantum mechanics explored with neutron interferometers

    OpenAIRE

    Klepp, J.; Sponar, S.; Hasegawa, Y.

    2014-01-01

    Ongoing fascination with quantum mechanics keeps driving the development of the wide field of quantum-optics, including its neutron-optics branch. Application of neutron-optical methods and, especially, neutron interferometry and polarimetry has a long-standing tradition for experimental investigations of fundamental quantum phenomena. We give an overview of related experimental efforts made in recent years.

  8. Evolutionary Psychology and the Explanation of Ethnic Phenomena

    Directory of Open Access Journals (Sweden)

    David B. Goetze

    2004-01-01

    Full Text Available In a recent series of articles, Hislope (1998, 2000 and Harvey (2000a, 2000b have raised questions about the usefulness of “evolutionary theory” especially for any purpose other than identifying “distal” causes of ethnic phenomena. This article responds to those views and argues that evolutionary psychology shows great promise in contributing to the explanation of contemporary ethnic identities and ethnic conflict. The authors argue that an evolutionary psychology approach embraces research conducted through conventional social science approaches, helps to complete explanations of the proximate causes of ethnic conflict, and can recast thought and encourage new areas of research about important issues in the ethnic conflict field. Illustrations are provided in support of each of these points. Some of these arguments have been heard before with respect to the general role of evolutionary theory in explaining social phenomena but they are arguments we think bear repeating and illustrating in the context of the study of ethnic phenomena. Before examining the ways that evolutionary psychology can contribute to social science explanation of ethnic phenomena, we summarize the general evolutionary psychology approach to the study of social behavior.

  9. Searches for new exotic phenomena at the LHC

    CERN Document Server

    Pachal, Katherine; The ATLAS collaboration

    2016-01-01

    The ATLAS and CMS detectors have collected about 3 fb^{-1} of proton-proton collisions at 13 TeV centre of mass energy during the 2015 LHC run. Results on searches for resonances decaying into vector bosons or fermions, for vector like quarks, for dark matter, for leptoquarks and for other new phenomena using these data will be presented.

  10. Nonlinear Hyperbolic-Parabolic System Modeling Some Biological Phenomena

    Institute of Scientific and Technical Information of China (English)

    WU Shaohua; CHEN Hua

    2011-01-01

    In this paper, we study a nonlinear hyperbolic-parabolic system modeling some biological phenomena. By semigroup theory and Leray-Schauder fixed point argument, the local existence and uniqueness of the weak solutions for this system are proved. For the spatial dimension N = 1, the global existence of the weak solution will be established by the bootstrap argument.

  11. Mirador - Atmospheric Composition

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Science data access made simple. Atmospheric Composition is focused on the composition of Earth's atmosphere in relation to climate prediction, solar effects,...

  12. Planetary Atmospheric Electricity

    CERN Document Server

    Leblanc, F; Yair, Y; Harrison, R. G; Lebreton, J. P; Blanc, M

    2008-01-01

    This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to t...

  13. Our shared atmosphere

    Science.gov (United States)

    Our atmosphere is a precious and fascinating resource, providing air to breath, shielding us from harmful ultraviolet radiation (UV), and maintaining a comfortable climate. Since the industrial revolution, people have significantly altered the composition of the atmosphere throu...

  14. From atmospheric awareness to active materiality

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2013-01-01

    surroundings, where the environmental qualities are implicit and conditions and phenomena are bound together in a reciprocal dependence. Therefore, material is neither seen as an isolated element, nor as mere substance expressing tectonic character. Transcending its generative potential and focusing on its...... of continuous and complex interferences revealed through our perception. Therefore, to design considering an atmospheric approach means to focus on how the space is going to appear, to be experienced or to be felt. What immediately follows this assumption is, then, the exploration of works and design processes...... with an attempt to trace associations and draw out design protocols, focusing on ways in which atmosphere can be consciously generated or manipulated. The aim is thus to examine ‘the atmospheric’ as a spatial quality, an experiential property as well as a sensory background and materiality as one...

  15. Advanced studies on Simulation Methodologies for very Complicated Fracture Phenomena

    Science.gov (United States)

    Nishioka, Toshihisa

    2010-06-01

    Although nowadays, computational techniques are well developed, for Extremely Complicated Fracture Phenomena, they are still very difficult to simulate, for general engineers, researchers. To overcome many difficulties in those simulations, we have developed not only Simulation Methodologies but also theoretical basis and concepts. We sometimes observe extremely complicated fracture patterns, especially in dynamic fracture phenomena such as dynamic crack branching, kinking, curving, etc. For examples, although the humankind, from primitive men to modern scientists such as Albert Einstein had watched the post-mortem patterns of dynamic crack branching, the governing condition for the onset of the phenomena had been unsolved until our experimental study. From in these studies, we found the governing condition of dynamic crack bifurcation, as follows. When the total energy flux per unit time into a propagating crack tip reaches the material crack resistance, the crack braches into two cracks [total energy flux criterion]. The crack branches many times whenever the criterion is satisfied. Furthermore, the complexities also arise due to their time-dependence and/or their-deformation dependence. In order to make it possible to simulate such extremely complicated fracture phenomena, we developed many original advanced computational methods and technologies. These are (i)moving finite element method based on Delaunay automatic triangulation (MFEMBOAT), path independent,(ii) equivalent domain integral expression of the dynamic J integral associated with a continuous auxiliary function,(iii) Mixed phase path-prediction mode simulation, (iv) implicit path prediction criterion. In this paper, these advanced computational methods are thoroughly explained together with successful comparison with the experimental results. Since multiple dynamic crack branching phenomena may be most complicated fracture due to complicated fracture paths, and its time dependence (transient), this

  16. Seasonality of alcohol-related phenomena in Estonia

    Science.gov (United States)

    Silm, Siiri; Ahas, Rein

    2005-03-01

    We studied alcohol consumption and its consequences as a seasonal phenomenon in Estonia and analysed the social and environmental factors that may cause its seasonal rhythm. There are two important questions when researching the seasonality of human activities: (1) whether it is caused by natural or social factors, and (2) whether the impact of the factors is direct or indirect. Often the seasonality of social phenomena is caused by social factors, but the triggering mechanisms are related to environmental factors like temperature, precipitation, and radiation via the circannual calendar. The indicators of alcohol consumption in the current paper are grouped as: (1) pre-consumption phenomena, i.e. production, tax and excise, sales (beer, wine and vodka are analysed separately), and (2) post-consumption phenomena, i.e. alcohol-related crime and traffic accidents and the number of people detained in lockups and admitted to alcohol treatment clinics. In addition, seasonal variability in the amount of alcohol advertising has been studied, and a survey has been carried out among 87 students of Tartu University. The analysis shows that different phenomena related to alcohol have a clear seasonal rhythm in Estonia. The peak period of phenomena related to beer is in the summer, from June to August and the low point is during the first months of the year. Beer consumption correlates well with air temperature. The consumption of vodka increases sharply at the end of the year and in June; the production of vodka does not have a significant correlation with negative temperatures. The consumption of wine increases during summer and in December. The consequences of alcohol consumption, expressed as the rate of traffic accidents or the frequency of medical treatment, also show seasonal variability. Seasonal variability of alcohol consumption in Estonia is influenced by natural factors (temperature, humidity, etc.) and by social factors (celebrations, vacations, etc.). However

  17. Primary Issues of Mixed Convection Heat Transfer Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Myeong-Seon; Chung, Bum-Jin [Kyung Hee University, Yongin (Korea, Republic of)

    2015-10-15

    The computer code analyzing the system operating and transient behavior must distinguish flow conditions involved with convective heat transfer flow regimes. And the proper correlations must be supplied to those flow regimes. However the existing safety analysis codes are focused on the Light Water Reactor and they are skeptical to be applied to the GCRs (Gas Cooled Reactors). One of the technical issues raise by the development of the VHTR is the mixed convection, which occur when the driving forces of both forced and natural convection are of comparable magnitudes. It can be encountered as in channel of the stacked with fuel elements and a decay heat removal system and in VHTR. The mixed convection is not intermediate phenomena with natural convection and forced convection but independent complicated phenomena. Therefore, many researchers have been studied and some primary issues were propounded for phenomena mixed convection. This paper is to discuss some problems identified through reviewing the papers for mixed convection phenomena. And primary issues of mixed convection heat transfer were proposed respect to thermal hydraulic problems for VHTR. The VHTR thermal hydraulic study requires an indepth study of the mixed convection phenomena. In this study we reviewed the classical flow regime map of Metais and Eckert and derived further issues to be considered. The following issues were raised: (1) Buoyancy aided an opposed flows were not differentiated and plotted in a map. (2) Experimental results for UWT and UHF condition were also plotted in the same map without differentiation. (3) The buoyancy coefficient was not generalized for correlating with buoyancy coefficient. (4) The phenomenon analysis for laminarization and returbulization as buoyancy effects in turbulent mixed convection was not established. (5) The defining to transition in mixed convection regime was difficult.

  18. Sub-photosphere to Solar Atmosphere Connection

    Science.gov (United States)

    Komm, Rudolf; De Moortel, Ineke; Fan, Yuhong; Ilonidis, Stathis; Steiner, Oskar

    2015-12-01

    Magnetic fields extend from the solar interior through the atmosphere. The formation and evolution of active regions can be studied by measuring subsurface flows with local helioseismology. The emergence of magnetic flux from the solar convection zone is associated with acoustic perturbation signatures. In near-surface layers, the average dynamics can be determined for emerging regions. MHD simulations of the emergence of a twisted flux tube show how magnetic twist and free energy are transported from the interior into the corona and the dynamic signatures associated with such transport in the photospheric and sub-photospheric layers. The subsurface twisted flux tube does not emerge into the corona as a whole in emerging active regions. Shear flows at the polarity inversion line and coherent vortical motions in the subsurface flux tubes are the major means by which twist is transported into the corona, leading to the formation of sigmoid-shaped coronal magnetic fields capable of driving solar eruptions. The transport of twist can be followed from the interior by using the kinetic helicity of subsurface flows as a proxy of magnetic helicity; this quantity holds great promise for improving the understanding of eruptive phenomena. Waves are not only vital for studying the link between the solar interior and the surface but for linking the photosphere with the corona as well. Acoustic waves that propagate from the surface into the magnetically structured, dynamic atmosphere undergo mode conversion and refraction. These effects enable atmospheric seismology to determine the topography of magnetic canopies in the solar atmosphere. Inclined magnetic fields lower the cut-off frequency so that low frequency waves can leak into the outer atmosphere. Recent high resolution, high cadence observations of waves and oscillations in the solar atmosphere, have lead to a renewed interest in the potential role of waves as a heating mechanism. In light of their potential contribution

  19. Atmospheric and accelerator neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yoichiro [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo Higashi-Mozumi, Kamioka, Hida-City, Gifu 506-1205 (Japan)

    2006-05-15

    Results from the atmospheric neutrino measurements are presented. Evidence for the {nu}{sub {tau}} appearance in the atmospheric neutrino events was shown by statistical methods. The long baseline oscillation experiment using man-made neutrinos has confirmed the atmospheric neutrino oscillation. The future accelerator experiments are briefly discussed.

  20. Atmospheric refraction : a history

    NARCIS (Netherlands)

    Lehn, WH; van der Werf, S

    2005-01-01

    We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of un

  1. Phenomena-based Process Synthesis and Design to achieve Process Intensification

    DEFF Research Database (Denmark)

    Lutze, Philip; Babi, Deenesh Kavi; Woodley, John

    2012-01-01

    at the lowest level of aggregation: phenomena. Therefore, in this paper, a phenomena-based synthesis/design methodology is presented. Using this methodology, a systematic identification of necessary and desirable (integrated) phenomena as well as generation and screening of phenomena-based flowsheet options...

  2. Sensitive versus Rough Dependence under Initial Conditions in Atmospheric Flow Regimes

    Directory of Open Access Journals (Sweden)

    Anthony R. Lupo

    2016-12-01

    Full Text Available In this work, we will identify the existence of “rough dependence on initial conditions” in atmospheric phenomena, a concept which is a problem for weather analysis and forecasting. Typically, two initially similar atmospheric states will diverge slowly over time such that forecasting the weather using the Navier-Stokes equations is useless after some characteristic time scale. With rough dependence, two initial states diverge very quickly, implying forecasting may be impossible. Using previous research in atmospheric science, rough dependence is characterized by using quantities that can be calculated using atmospheric data and quantities. Rough dependence will be tested for and identified in atmospheric phenomena at different time scales using case studies. Data were provided for this project by archives outside the University of Missouri (MU and by using the MU RADAR at the South Farm experiment station.

  3. The role of cosmic rays in the Earth’s atmospheric processes

    Indian Academy of Sciences (India)

    Devendraa Siingh; R P Singh

    2010-01-01

    In this paper, we have provided an overview of cosmic ray effects on terrestrial processes such as electrical properties, global electric circuit, lightning, cloud formation, cloud coverage, atmospheric temperature, space weather phenomena, climate, etc. It is suggested that cosmic rays control short-term and long-term variations in climate. There are many basic phenomena which need further study and require new and long-term data set. Some of these have been pointed out.

  4. Atmospheric Habitable Zones in Y Dwarf Atmospheres

    Science.gov (United States)

    Yates, Jack S.; Palmer, Paul I.; Biller, Beth; Cockell, Charles S.

    2017-02-01

    We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. To illustrate our model, we use a cool Y dwarf atmosphere, such as WISE J085510.83–0714442.5, whose 4.5–5.2 μm spectrum shows absorption features consistent with water vapor and clouds. We allow organisms to adapt to their atmospheric environment (described by temperature, convection, and gravity) by adopting different growth strategies that maximize their chance of survival and proliferation. We assume a constant upward vertical velocity through the AHZ. We found that the organism growth strategy is most sensitive to the magnitude of the atmospheric convection. Stronger convection supports the evolution of more massive organisms. For a purely radiative environment, we find that evolved organisms have a mass that is an order of magnitude smaller than terrestrial microbes, thereby defining a dynamical constraint on the dimensions of life that an AHZ can support. Based on a previously defined statistical approach, we infer that there are of the order of 109 cool Y brown dwarfs in the Milky Way, and likely a few tens of these objects are within 10 pc from Earth. Our work also has implications for exploring life in the atmospheres of temperate gas giants. Consideration of the habitable volumes in planetary atmospheres significantly increases the volume of habitable space in the galaxy.

  5. Multipoint observations of plasma phenomena made in space by Cluster

    Science.gov (United States)

    Goldstein, M. L.; Escoubet, P.; Hwang, K.-Joo; Wendel, D. E.; Viñas, A.-F.; Fung, S. F.; Perri, S.; Servidio, S.; Pickett, J. S.; Parks, G. K.; Sahraoui, F.; Gurgiolo, C.; Matthaeus, W.; Weygand, J. M.

    2015-06-01

    Plasmas are ubiquitous in nature, surround our local geospace environment, and permeate the universe. Plasma phenomena in space give rise to energetic particles, the aurora, solar flares and coronal mass ejections, as well as many energetic phenomena in interstellar space. Although plasmas can be studied in laboratory settings, it is often difficult, if not impossible, to replicate the conditions (density, temperature, magnetic and electric fields, etc.) of space. Single-point space missions too numerous to list have described many properties of near-Earth and heliospheric plasmas as measured both in situ and remotely (see http://www.nasa.gov/missions/#.U1mcVmeweRY for a list of NASA-related missions). However, a full description of our plasma environment requires three-dimensional spatial measurements. Cluster is the first, and until data begin flowing from the Magnetospheric Multiscale Mission (MMS), the only mission designed to describe the three-dimensional spatial structure of plasma phenomena in geospace. In this paper, we concentrate on some of the many plasma phenomena that have been studied using data from Cluster. To date, there have been more than 2000 refereed papers published using Cluster data but in this paper we will, of necessity, refer to only a small fraction of the published work. We have focused on a few basic plasma phenomena, but, for example, have not dealt with most of the vast body of work describing dynamical phenomena in Earth's magnetosphere, including the dynamics of current sheets in Earth's magnetotail and the morphology of the dayside high latitude cusp. Several review articles and special publications are available that describe aspects of that research in detail and interested readers are referred to them (see for example, Escoubet et al. 2005 Multiscale Coupling of Sun-Earth Processes, p. 459, Keith et al. 2005 Sur. Geophys. 26, 307-339, Paschmann et al. 2005 Outer Magnetospheric Boundaries: Cluster Results, Space Sciences Series

  6. Causal mechanisms of seismo-EM phenomena during the 1965-1967 Matsushiro earthquake swarm.

    Science.gov (United States)

    Enomoto, Yuji; Yamabe, Tsuneaki; Okumura, Nobuo

    2017-03-21

    The 1965-1967 Matsushiro earthquake swarm in central Japan exhibited two unique characteristics. The first was a hydro-mechanical crust rupture resulting from degassing, volume expansion of CO2/water, and a crack opening within the critically stressed crust under a strike-slip stress. The other was, despite the lower total seismic energy, the occurrence of complexed seismo-electromagnetic (seismo-EM) phenomena of the geomagnetic intensity increase, unusual earthquake lights (EQLs) and atmospheric electric field (AEF) variations. Although the basic rupture process of this swarm of earthquakes is reasonably understood in terms of hydro-mechanical crust rupture, the associated seismo-EM processes remain largely unexplained. Here, we describe a series of seismo-EM mechanisms involved in the hydro-mechanical rupture process, as observed by coupling the electric interaction of rock rupture with CO2 gas and the dielectric-barrier discharge of the modelled fields in laboratory experiments. We found that CO2 gases passing through the newly created fracture surface of the rock were electrified to generate pressure-impressed current/electric dipoles, which could induce a magnetic field following Biot-Savart's law, decrease the atmospheric electric field and generate dielectric-barrier discharge lightning affected by the coupling effect between the seismic and meteorological activities.

  7. Causal mechanisms of seismo-EM phenomena during the 1965–1967 Matsushiro earthquake swarm

    Science.gov (United States)

    Enomoto, Yuji; Yamabe, Tsuneaki; Okumura, Nobuo

    2017-01-01

    The 1965–1967 Matsushiro earthquake swarm in central Japan exhibited two unique characteristics. The first was a hydro-mechanical crust rupture resulting from degassing, volume expansion of CO2/water, and a crack opening within the critically stressed crust under a strike-slip stress. The other was, despite the lower total seismic energy, the occurrence of complexed seismo-electromagnetic (seismo-EM) phenomena of the geomagnetic intensity increase, unusual earthquake lights (EQLs) and atmospheric electric field (AEF) variations. Although the basic rupture process of this swarm of earthquakes is reasonably understood in terms of hydro-mechanical crust rupture, the associated seismo-EM processes remain largely unexplained. Here, we describe a series of seismo-EM mechanisms involved in the hydro-mechanical rupture process, as observed by coupling the electric interaction of rock rupture with CO2 gas and the dielectric-barrier discharge of the modelled fields in laboratory experiments. We found that CO2 gases passing through the newly created fracture surface of the rock were electrified to generate pressure-impressed current/electric dipoles, which could induce a magnetic field following Biot-Savart’s law, decrease the atmospheric electric field and generate dielectric-barrier discharge lightning affected by the coupling effect between the seismic and meteorological activities.

  8. Computational transport phenomena of fluid-particle systems

    CERN Document Server

    Arastoopour, Hamid; Abbasi, Emad

    2017-01-01

    This book concerns the most up-to-date advances in computational transport phenomena (CTP), an emerging tool for the design of gas-solid processes such as fluidized bed systems. The authors examine recent work in kinetic theory and CTP and illustrate gas-solid processes’ many applications in the energy, chemical, pharmaceutical, and food industries. They also discuss the kinetic theory approach in developing constitutive equations for gas-solid flow systems and how it has advanced over the last decade as well as the possibility of obtaining innovative designs for multiphase reactors, such as those needed to capture CO2 from flue gases. Suitable as a concise reference and a textbook supplement for graduate courses, Computational Transport Phenomena of Gas-Solid Systems is ideal for practitioners in industries involved with the design and operation of processes based on fluid/particle mixtures, such as the energy, chemicals, pharmaceuticals, and food processing. Explains how to couple the population balance e...

  9. Autoscopic phenomena and one's own body representation in dreams.

    Science.gov (United States)

    Occhionero, Miranda; Cicogna, Piera Carla

    2011-12-01

    Autoscopic phenomena (AP) are complex experiences that include the visual illusory reduplication of one's own body. From a phenomenological point of view, we can distinguish three conditions: autoscopic hallucinations, heautoscopy, and out-of-body experiences. The dysfunctional pattern involves multisensory disintegration of personal and extrapersonal space perception. The etiology, generally either neurological or psychiatric, is different. Also, the hallucination of Self and own body image is present during dreams and differs according to sleep stage. Specifically, the representation of the Self in REM dreams is frequently similar to the perception of Self in wakefulness, whereas in NREM dreams, a greater polymorphism of Self and own body representation is observed. The parallels between autoscopic phenomena in pathological cases and the Self-hallucination in dreams will be discussed to further the understanding of the particular states of self awareness, especially the complex integration of different memory sources in Self and body representation.

  10. Stochastic Car-Following Model for Explaining Nonlinear Traffic Phenomena

    Science.gov (United States)

    Meng, Jianping; Song, Tao; Dong, Liyun; Dai, Shiqiang

    There is a common time parameter for representing the sensitivity or the lag (response) time of drivers in many car-following models. In the viewpoint of traffic psychology, this parameter could be considered as the perception-response time (PRT). Generally, this parameter is set to be a constant in previous models. However, PRT is actually not a constant but a random variable described by the lognormal distribution. Thus the probability can be naturally introduced into car-following models by recovering the probability of PRT. For demonstrating this idea, a specific stochastic model is constructed based on the optimal velocity model. By conducting simulations under periodic boundary conditions, it is found that some important traffic phenomena, such as the hysteresis and phantom traffic jams phenomena, can be reproduced more realistically. Especially, an interesting experimental feature of traffic jams, i.e., two moving jams propagating in parallel with constant speed stably and sustainably, is successfully captured by the present model.

  11. Sixth Microgravity Fluid Physics and Transport Phenomena Conference Abstracts

    Science.gov (United States)

    Singh, Bhim (Compiler)

    2002-01-01

    The Sixth Microgravity Fluid Physics and Transport Phenomena Conference provides the scientific community the opportunity to view the current scope of the Microgravity Fluid Physics and Transport Phenomena Program, current research opportunities, and plans for the near future. The conference focuses not only on fundamental research but also on applications of this knowledge towards enabling future space exploration missions. A whole session dedicated to biological fluid physics shows increased emphasis that the program has placed on interdisciplinary research. The conference includes invited plenary talks, technical paper presentations, poster presentations, and exhibits. This TM is a compilation of abstracts of the papers and the posters presented at the conference. Web-based proceedings, including the charts used by the presenters, will be posted on the web shortly after the conference.

  12. Critical phenomena: 150 years since Cagniard de la Tour

    CERN Document Server

    Berche, Bertrand; Kenna, Ralph

    2009-01-01

    Critical phenomena were discovered by Cagniard de la Tour in 1822, who died 150 years ago. In order to mark this anniversary, the context and the early history of his discovery is reviewed. We then follow with a brief sketch of the history of critical phenomena, indicating the main lines of development until the present date. Os fen\\'omenos cr\\'{\\i}ticos foram descobertos pelo Cagniard de la Tour em Paris em 1822. Para comemorar os 150 anos da sua morte, o contexto e a hist\\'oria initial da sua descoberta \\'e contada. Conseguimos com uma descri\\c{c}\\~ao breve da hist\\'oria dos fen\\'emenos cr\\'{\\i}ticos, indicando as linhas principais do desenvolvimento at\\'e o presente.

  13. IUTAM Symposium on Fracture Phenomena in Nature and Technology

    CERN Document Server

    Carini, Angelo; Gei, Massimiliano; Salvadori, Alberto

    2014-01-01

    This book contains contributions presented at the IUTAM Symposium "Fracture Phenomena in Nature and Technology" held in Brescia, Italy, 1-5 July, 2012.The objective of the Symposium was fracture research, interpreted broadly to include new engineering and structural mechanics treatments of damage development and crack growth, and also large-scale failure processes as exemplified by earthquake or landslide failures, ice shelf break-up, and hydraulic fracturing (natural, or for resource extraction or CO2 sequestration), as well as small-scale rupture phenomena in materials physics including, e.g., inception of shear banding, void growth, adhesion and decohesion in contact and friction, crystal dislocation processes, and atomic/electronic scale treatment of brittle crack tips and fundamental cohesive properties.Special emphasis was given to multiscale fracture description and new scale-bridging formulations capable to substantiate recent experiments and tailored to become the basis for innovative computationa...

  14. Turbulent Phenomena in the Aerobreakup of Liquid Droplets

    Directory of Open Access Journals (Sweden)

    Andras Horvath

    2012-09-01

    Full Text Available This work presents the computational simulation results of turbulent phenomena in a high velocity multiphase flow, where the predominantly turbulent phase is the gaseous phase. For reliable simulation results the code is validated by comparing results of a single phase supersonic turbulent flow to other simulation and experimental results and good agreement is found. This is a precondition for the simulation of the initial stages of the breakup of a liquid droplet in a high Weber number flow. The role of the subgrid-scale turbulence is investigated and two distinct regions are identified. In the second region turbulence phenomena seem to be the predominant factors for the characteristic shape. Simulation results are compared to experiments of the droplet breakup at high Weber number.

  15. Ecological momentary assessment (EMA) of depression-related phenomena.

    Science.gov (United States)

    Armey, Michael F; Schatten, Heather T; Haradhvala, Natasha; Miller, Ivan W

    2015-08-01

    Ecological momentary assessment (EMA) is one research method increasingly employed to better understand the processes that underpin depression and related phenomena. In particular, EMA is well suited to the study of affect (e.g., positive and negative affect), affective responses to stress (e.g., emotion reactivity), and behaviors (e.g., activity level, sleep) that are associated with depression. Additionally, EMA can provide insights into self-harm behavior (i.e. suicide and non-suicidal self-injury), and other mood disorders (e.g. bipolar disorder) commonly associated with depressive episodes. Given the increasing availability and affordability of handheld computing devices such as smartphones, EMA is likely to play an increasingly important role in the study of depression and related phenomena in the future.

  16. A NOVEL APPROACH FOR ELECTROKINETIC PHENOMENA IN SOFT MATTER

    Directory of Open Access Journals (Sweden)

    JUAN P. HERNANDEZ-ORTIZ

    2012-01-01

    Full Text Available Electrokinetic phenomena controls and drives many interactions in soft matter physics. In biology, for example, many of living functions are derived from complicated electrokinetic phenomena that interrelates cells, solvents, ions, solutes and tissues. This paper defines, explores and provides a novel method towards the analysis and understanding of such problems. The new method is a generalization of the General Geometry Ewald-like Method (GGEM; it combines continuum and statistical mechanics through a Green’s function formalism for the long-range interactions. In this way, the separation of time and length scales, commonly encountered in soft matter fluids, is avoided. The fundamental equations behind electrokinetic problems are exposed and the paper finishes with a description of the novel Nernst-Planck-GGEM approach.

  17. Visible and invisible the wonders of light phenomena

    CERN Document Server

    Bisi, Olmes

    2015-01-01

    Light phenomena have intrigued humankind since prehistory. Think of the rainbow, a sunset on the sea, a game of shadows. Humans have always used light for their own needs, from cooking food to illuminating a room. However, light is not only limited to what we can see with our eyes. The invisible part of the electromagnetic spectrum is broad and dynamic. This book outlines the mysteries and wonders of electromagnetism, heat, and light. It also covers the history of our scientific understanding of light. The dark as well as the bright sides of light are fully explored in these pages, from their impact on our world to their use in cutting-edge technologies in a variety of fields. Numerous full-color images and drawings complement the text, and light phenomena are explained in a simple and engaging way.

  18. High-Pressure Crystallography From Fundamental Phenomena to Technological Applications

    CERN Document Server

    Boldyreva, Elena

    2010-01-01

    This book is devoted to the theme of crystallographic studies at high pressure, with emphasis on the phenomena characteristic to the compressed state of matter, as well as experimental and theoretical techniques used to study these phenomena. As a thermodynamic parameter, pressure is remarkable in many ways. In the visible universe its value spans over sixty orders of magnitude, from the non-equilibrium pressure of hydrogen in intergalactic space, to the kind of pressure encountered within neutron stars. In the laboratory, it provides the unique possibility to control the structure and properties of materials, to dramatically alter electronic properties, and to break existing, or form new chemical bonds. This agenda naturally encompasses elements of physics (properties, structure and transformations), chemistry (reactions, transport), materials science (new materials) and engineering (mechanical properties); in addition it has direct applications and implications for geology (minerals in deep Earth environmen...

  19. Musical obsessions: a comprehensive review of neglected clinical phenomena.

    Science.gov (United States)

    Taylor, Steven; McKay, Dean; Miguel, Euripedes C; De Mathis, Maria Alice; Andrade, Chittaranjan; Ahuja, Niraj; Sookman, Debbie; Kwon, Jun Soo; Huh, Min Jung; Riemann, Bradley C; Cottraux, Jean; O'Connor, Kieron; Hale, Lisa R; Abramowitz, Jonathan S; Fontenelle, Leonardo F; Storch, Eric A

    2014-08-01

    Intrusive musical imagery (IMI) consists of involuntarily recalled, short, looping fragments of melodies. Musical obsessions are distressing, impairing forms of IMI that merit investigation in their own right and, more generally, research into these phenomena may broaden our understanding of obsessive-compulsive disorder (OCD), which is phenomenologically and etiologically heterogeneous. We present the first comprehensive review of musical obsessions, based on the largest set of case descriptions ever assembled (N=96). Characteristics of musical obsessions are described and compared with normal IMI, musical hallucinations, and visual obsessional imagery. Assessment, differential diagnosis, comorbidity, etiologic hypotheses, and treatments are described. Musical obsessions may be under-diagnosed because they are not adequately assessed by current measures of OCD. Musical obsessions have been misdiagnosed as psychotic phenomena, which has led to ineffective treatment. Accurate diagnosis is important for appropriate treatment. Musical obsessions may respond to treatments that are not recommended for prototypic OCD symptoms.

  20. Purcell effect and Lamb shift as interference phenomena

    Science.gov (United States)

    Rybin, Mikhail V.; Mingaleev, Sergei F.; Limonov, Mikhail F.; Kivshar, Yuri S.

    2016-02-01

    The Purcell effect and Lamb shift are two well-known physical phenomena which are usually discussed in the context of quantum electrodynamics, with the zero-point vibrations as a driving force of those effects in the quantum approach. Here we discuss the classical counterparts of these quantum effects in photonics, and explain their physics trough interference wave phenomena. As an example, we consider a waveguide in a planar photonic crystal with a side-coupled defect, and demonstrate a perfect agreement between the results obtained on the basis of quantum and classic approaches and reveal their link to the Fano resonance. We find that in such a waveguide-cavity geometry the Purcell effect can modify the lifetime by at least 25 times, and the Lamb shift can exceed 3 half-widths of the cavity spectral line.

  1. Dispersion phenomena in helical flow in a concentric annulus.

    Science.gov (United States)

    Song, Young Seok; Brenner, Howard

    2009-12-14

    We examined dispersion phenomena of solutes in helical flow in a concentric annulus through a multiscale approach. The helical flow was developed by the combination of the Poiseuille flow and Couette flow. Here, we present an analytic model that can address the multidimensional Taylor dispersion in the helical flow under a lateral field of thermophoresis (or thermal diffusion) in the gapwise direction. Macroscopic parameters including the average solute velocity and dispersivity were analyzed using relevant microscopic physicochemical properties. The mathematically obtained results were validated by the numerical simulation carried out in this study. The findings show that macrotransport processes are robust and straightforward to handle multidimensional dispersion phenomena of solutes in helical flow. This study is expected to provide a theoretical platform for applications of helical flow such as tube exchangers, oil drilling, and multidimensional field flow fractionations (e.g., helical flow field flow fractionation).

  2. Tank Pressure Control Experiment/thermal Phenomena (TPCE/TP)

    Science.gov (United States)

    Hasan, M. M.; Knoll, R. H.

    1992-01-01

    The 'Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP)' is a reflight of the tank pressure control experiment (TPCE), flown on STS-43 in a standard Get-Away Special (GAS) container in August 1991. The TPCE obtained extensive video and digital data of the jet induced mixing process in a partially filled tank in low gravity environments. It also provided limited data on the thermal processes involved. The primary objective of the reflight of TPCE is to investigate experimentally the phenomena of liquid superheating and pool nucleate boiling at very low heat fluxes in a long duration low gravity environment. The findings of this experiment will be of direct relevance to space based subcritical cryogenic fluid system design and operation. Experiment hardware and results from the first TPCE are described in outline and graphic form.

  3. Critical phenomena in one dimension from a Bethe ansatz perspective

    Science.gov (United States)

    Guan, Xiwen

    2014-08-01

    This article briefly reviews recent theoretical developments in quantum critical phenomena in one-dimensional (1D) integrable quantum gases of cold atoms. We present a discussion on quantum phase transitions, universal thermodynamics, scaling functions and correlations for a few prototypical exactly solved models, such as the Lieb-Liniger Bose gas, the spin-1 Bose gas with antiferromagnetic spin-spin interaction, the two-component interacting Fermi gas as well as spin-3/2 Fermi gases. We demonstrate that their corresponding Bethe ansatz solutions provide a precise way to understand quantum many-body physics, such as quantum criticality, Luttinger liquids (LLs), the Wilson ratio, Tan's Contact, etc. These theoretical developments give rise to a physical perspective using integrability for uncovering experimentally testable phenomena in systems of interacting bosonic and fermonic ultracold atoms confined to 1D.

  4. Autoscopic phenomena: case report and review of literature

    Directory of Open Access Journals (Sweden)

    Thomas Astrid

    2011-01-01

    Full Text Available Abstract Background Autoscopic phenomena are psychic illusory visual experiences consisting of the perception of the image of one's own body or face within space, either from an internal point of view, as in a mirror or from an external point of view. Descriptions based on phenomenological criteria distinguish six types of autoscopic experiences: autoscopic hallucination, he-autoscopy or heautoscopic proper, feeling of a presence, out of body experience, negative and inner forms of autoscopy. Methods and results We report a case of a patient with he-autoscopic seizures. EEG recordings during the autoscopic experience showed a right parietal epileptic focus. This finding confirms the involvement of the temporo-parietal junction in the abnormal body perception during autoscopic phenomena. We discuss and review previous literature on the topic, as different localization of cortical areas are reported suggesting that out of body experience is generated in the right hemisphere while he-autoscopy involves left hemisphere structures.

  5. On the Cosmological Aspects of Observed High Energy Cosmic Phenomena

    CERN Document Server

    Vankov, A

    1999-01-01

    Super-high energy corpuscular and gamma rays as well as cosmic high--power density sources are hard to explain in a galaxy model framework. Attempts to include some of those phenomena in the Standard Cosmological Model also encounter serious difficulties. In the present paper an alternative cosmological concept is discussed. There are several features in it. First of all, the whole Universe (Grand Universe) is a multitude of typical universes, like ours, evenly made of either matter or antimatter, hence, there is no violation of the baryon symmetry on the largest scale. Second, high-energy phenomena are the result of matter-antimatter annihilation processes in a typical universe evolution. Finally, the Ground Universe is a self-creating due to a balance of annihilation and pair creation in the inter-universe infinite space. This concept and its consistence with the major observational data are discussed in detail.

  6. A Retrospection of Chaotic Phenomena in Electrical Systems

    Directory of Open Access Journals (Sweden)

    Umesh Kumar

    1998-01-01

    Full Text Available In the last decade new phenomena have been observed in all areas of non linear dynamics, principal among these being ‘Chaotic phenomena’. Chaos has been reported virtually from every scientific discipline. This paper summarizes a study of the chaotic phenomena in electrical systems and attempts to translate the mathematical ideas and techniques into language that engineers and applied scientists can use to study ‘Chaos’. Towards this end, the paper has summarized the study of chaos in several examples like Chua’s circuit family; Folded Torus circuit; non-autonomous circuits; switched capacitor circuits and hyper-chaos circuits. As observed in power systems, control systems and digital filters, chaos has been exhibited and shown on examples.

  7. Adsorption phenomena and anchoring energy in nematic liquid crystals

    CERN Document Server

    Barbero, Giovanni

    2005-01-01

    Despite the large quantity of phenomenological information concerning the bulk properties of nematic phase liquid crystals, little is understood about the origin of the surface energy, particularly the surface, interfacial, and anchoring properties of liquid crystals that affect the performance of liquid crystal devices. Self-contained and unique, Adsorption Phenomena and Anchoring Energy in Nematic Liquid Crystals provides an account of new and established results spanning three decades of research into the problems of anchoring energy and adsorption phenomena in liquid crystals.The book contains a detailed discussion of the origin and possible sources of anchoring energy in nematic liquid crystals, emphasizing the dielectric contribution to the anchoring energy in particular. Beginning with fundamental surface and anchoring properties of liquid crystals and the definition of the nematic phase, the authors explain how selective ion adsorption, dielectric energy density, thickness dependence, and bias voltage...

  8. Emergence of dynamical order synchronization phenomena in complex systems

    CERN Document Server

    Manrubia, Susanna C; Zanette, Damián H

    2004-01-01

    Synchronization processes bring about dynamical order and lead tospontaneous development of structural organization in complex systemsof various origins, from chemical oscillators and biological cells tohuman societies and the brain. This book provides a review and adetailed theoretical analysis of synchronization phenomena in complexsystems with different architectures, composed of elements withperiodic or chaotic individual dynamics. Special attention is paid tostatistical concepts, such as nonequilibrium phase transitions, orderparameters and dynamical glasses.

  9. Basic phenomena utilised in aerosol particle measurement techniques; Hiukkasmittaustekniikoiden perusilmioet

    Energy Technology Data Exchange (ETDEWEB)

    Janka, K. [Dekati Oy, Tampere (Finland)

    2006-10-15

    The project deals with development of basic phenomena and mechanism utilised in aerosol particle measurement techniques. The areas under development are: particle-charging techniques, photoelectric charging, particle concentrating using virtual-impactor technique, and optical characterising techniques of particles. Results will be applied on detection techniques of bioaerosol attract, particle emission sensors for diesel exhaust gases, and widening the application areas of existing measurement techniques. (orig.)

  10. Phenomena of charged particles transport in variable magnetic fields

    CERN Document Server

    Savane, S Y; Faza-Barry, M; Vladmir, L

    2002-01-01

    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.

  11. Some Nonlinear Phenomena in a Preformed Underdense Plasma

    Institute of Scientific and Technical Information of China (English)

    曹莉华; 刘智勇; 常文蔚; 岳宗五

    2001-01-01

    The propagation of a laser pulse with a peak intensity 1019 W/cm2 through the preformed underdense plasmawith the density 0.014nc are studied by using two-dimensional particle-in-cell simulations. The longitudinal electron heating is identified and verified, and its major property agrees with the theoretical prediction. The electron distributions in phase space, patterns of the electric fields, profiles of the ion or electron density and other plasma nonlinear phenomena are presented and discussed.

  12. Two phenomena: Honji instability, and ringing of offshore structures

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streaming flow induced by the cylinder's boundary layer. Its oscillation period is half of the period of the cylinder oscillation. Finite volume calculations of the filtered Navier-Stokes equations visualize the three-dimensional instability, where fluid particles transported by the circumferencial rol...

  13. Dynamical system analysis of unstable flow phenomena in centrifugal blower

    Directory of Open Access Journals (Sweden)

    Garcia David

    2015-09-01

    Full Text Available Methods of dynamical system analysis were employed to analyze unsteady phenomena in a centrifugal blower. Pressure signals gathered at different control points were decomposed into their Principal Components (PCs by means of Singular Spectrum Analysis (SSA. Certain number of PCs was considered in the analysis based on their statistical correlation. Projection of the original signal onto its PCs allowed to draw the phase trajectory that clearly separated non-stable blower working conditions from its regular operation.

  14. Investigating Dissolution and Precipitation Phenomena with a Smartphone Microscope

    Energy Technology Data Exchange (ETDEWEB)

    Lumetta, Gregg J.; Arcia, Edgar

    2016-10-11

    A novel smartphone microscope can be used to observe the dissolution and crystallization of sodium chloride at a microscopic level. Observation of these seemingly simple phenomena through the microscope at 100× magnification can actually reveal some surprising behavior. These experiments offer the opportunity to discuss some basic concepts such as how the morphological features of the crystals dictates how the dissolution process proceeds, and how materials can be purified by re-crystallization techniques.

  15. Thermal dynamics of thermoelectric phenomena from frequency resolved methods

    OpenAIRE

    2016-01-01

    Understanding the dynamics of thermoelectric (TE) phenomena is important for the detailed knowledge of the operation of TE materials and devices. By analyzing the impedance response of both a single TE element and a TE device under suspended conditions, we provide new insights into the thermal dynamics of these systems. The analysis is performed employing parameters such as the thermal penetration depth, the characteristic thermal diffusion frequency and the thermal diffusion time. It is show...

  16. Investigating paranormal phenomena: Functional brain imaging of telepathy

    OpenAIRE

    Venkatasubramanian Ganesan; Jayakumar Peruvumba; Nagendra Hongasandra; Nagaraja Dindagur; Deeptha R; Gangadhar Bangalore

    2008-01-01

    Aim: "Telepathy" is defined as "the communication of impressions of any kind from one mind to another, independently of the recognized channels of sense". Meta-analyses of "ganzfield" studies as well as "card-guessing task" studies provide compelling evidence for the existence of telepathic phenomena. The aim of this study was to elucidate the neural basis of telepathy by examining an individual with this special ability. Materials and Methods: Using functional MRI, we examined a famous "m...

  17. New dynamic critical phenomena in nuclear and quark superfluids

    CERN Document Server

    Sogabe, Noriyuki

    2016-01-01

    We study the dynamic critical phenomena near the possible high-density QCD critical point inside the superfluid phase of nuclear and quark matter. We find that this critical point belongs to a new dynamic universality class beyond the conventional classification by Hohenberg and Halperin. We show that the speed of the superfluid phonon vanishes at the critical point and that the dynamic critical index is $z \\approx 2$.

  18. Search for Higgs and new phenomena at colliders

    Energy Technology Data Exchange (ETDEWEB)

    Lammel, Stephan; /Fermilab

    2006-01-01

    The present status of searches for the Higgs boson(s) and new phenomena is reviewed. The focus is on analyses and results from the current runs of the HERA and Tevatron experiments. The LEP experiments have released their final combined MSSM Higgs results for this conference. Also included are results from sensitivity studies of the LHC experiments and lepton flavor violating searches from the B factories, KEKB and PEP-II.

  19. Glass transition phenomena applied to powdered amorphous food carbohydrates

    OpenAIRE

    Ronkart, Sebastien N; Blecker, Christophe; Deroanne, Claude; Paquot, Michel

    2009-01-01

    Glass transition phenomena applied to powdered amorphous food carbohydrates. During these last fifteen years, some food technologists and scientists have become aware of the importance of the glass transition, a thermal property of glassy or amorphous material, in food preparation processes. Recent studies have successfully correlated this fundamental notion to technofunctional changes within the powder. The aim of this paper is to present in a non exhaustive manner the relationship between g...

  20. Fourth DOE Natural Phenomena Hazards Mitigation Conference: Proceedings. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This conference allowed an interchange in the natural phenomena area among designers, safety professionals, and managers. The papers presented in Volume I of the proceedings are from sessions I - VIII which cover the general topics of: DOE standards, lessons learned and walkdowns, wind, waste tanks, ground motion, testing and materials, probabilistic seismic hazards, risk assessment, base isolation and energy dissipation, and lifelines and floods. Individual papers are indexed separately. (GH)

  1. Research in Antenna Technology, Radar Technology and Electromagnetic Scattering Phenomena

    Science.gov (United States)

    2015-04-06

    AFRL-OSR-VA-TR-2015-0081 Research in Antenna Technology John Schindler ARCON CORP Final Report 04/06/2015 DISTRIBUTION A: Distribution approved for...a group of six researchers in the fields of electromagnetics, radar and antenna technology. Research was conducted during this reporting period in...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Research in Antenna technology, Radar Technology and Electromagnetic Scattering Phenomena

  2. Preface: cardiac control pathways: signaling and transport phenomena.

    Science.gov (United States)

    Sideman, Samuel

    2008-03-01

    Signaling is part of a complex system of communication that governs basic cellular functions and coordinates cellular activity. Transfer of ions and signaling molecules and their interactions with appropriate receptors, transmembrane transport, and the consequent intracellular interactions and functional cellular response represent a complex system of interwoven phenomena of transport, signaling, conformational changes, chemical activation, and/or genetic expression. The well-being of the cell thus depends on a harmonic orchestration of all these events and the existence of control mechanisms that assure the normal behavior of the various parameters involved and their orderly expression. The ability of cells to sustain life by perceiving and responding correctly to their microenvironment is the basis for development, tissue repair, and immunity, as well as normal tissue homeostasis. Natural deviations, or human-induced interference in the signaling pathways and/or inter- and intracellular transport and information transfer, are responsible for the generation, modulation, and control of diseases. The present overview aims to highlight some major topics of the highly complex cellular information transfer processes and their control mechanisms. Our goal is to contribute to the understanding of the normal and pathophysiological phenomena associated with cardiac functions so that more efficient therapeutic modalities can be developed. Our objective in this volume is to identify and enhance the study of some basic passive and active physical and chemical transport phenomena, physiological signaling pathways, and their biological consequences.

  3. Transport phenomena and drying of solids and particulate materials

    CERN Document Server

    Lima, AG

    2014-01-01

    The purpose of this book, Transport Phenomena and Drying of Solids and Particulate Materials, is to provide a collection of recent contributions in the field of heat and mass transfer, transport phenomena, drying and wetting of solids and particulate materials. The main benefit of the book is that it discusses some of the most important topics related to the heat and mass transfer in solids and particulate materials. It includes a set of new developments in the field of basic and applied research work on the physical and chemical aspects of heat and mass transfer phenomena, drying and wetting processes, namely, innovations and trends in drying science and technology, drying mechanism and theory, equipment, advanced modelling, complex simulation and experimentation. At the same time, these topics will be going to the encounter of a variety of scientific and engineering disciplines. The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional c...

  4. Superfluous neuroscience information makes explanations of psychological phenomena more appealing.

    Science.gov (United States)

    Fernandez-Duque, Diego; Evans, Jessica; Christian, Colton; Hodges, Sara D

    2015-05-01

    Does the presence of irrelevant neuroscience information make explanations of psychological phenomena more appealing? Do fMRI pictures further increase that allure? To help answer these questions, 385 college students in four experiments read brief descriptions of psychological phenomena, each one accompanied by an explanation of varying quality (good vs. circular) and followed by superfluous information of various types. Ancillary measures assessed participants' analytical thinking, beliefs on dualism and free will, and admiration for different sciences. In Experiment 1, superfluous neuroscience information increased the judged quality of the argument for both good and bad explanations, whereas accompanying fMRI pictures had no impact above and beyond the neuroscience text, suggesting a bias that is conceptual rather than pictorial. Superfluous neuroscience information was more alluring than social science information (Experiment 2) and more alluring than information from prestigious "hard sciences" (Experiments 3 and 4). Analytical thinking did not protect against the neuroscience bias, nor did a belief in dualism or free will. We conclude that the "allure of neuroscience" bias is conceptual, specific to neuroscience, and not easily accounted for by the prestige of the discipline. It may stem from the lay belief that the brain is the best explanans for mental phenomena.

  5. 8th International symposium on transport phenomena in combustion

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The 8th International Symposium on Transport Phenomena in Combustion will be held in San Francisco, California, U.S.A., July 16-20, 1995, under the auspices of the Pacific Center of Thermal-Fluids Engineering. The purpose of the Symposium is to provide a forum for researchers and practitioners from around the world to present new developments and discuss the state of the art and future directions and priorities in the areas of transport phenomena in combustion. The Symposium is the eighth in a series; previous venues were Honolulu 1985, Tokyo 1987, Taipei 1988, Sydney 1991, Beijing 1992, Seoul 1993 and Acapulco 1994, with emphasis on various aspects of transport phenomena. The current Symposium theme is combustion. The Symposium has assembled a balanced program with topics ranging from fundamental research to contemporary applications of combustion theory. Invited keynote lecturers will provide extensive reviews of topics of great interest in combustion. Colloquia will stress recent advances and innovations in fire spread and suppression, and in low NO{sub x} burners, furnaces, boilers, internal combustion engines, and other practical combustion systems. Finally, numerous papers will contribute to the fundamental understanding of complex processes in combustion. This document contains abstracts of papers to be presented at the Symposium.

  6. Toward a CFD-grade database addressing LWR containment phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Paladino, Domenico, E-mail: domenico.paladino@psi.ch [Laboratory for Thermal-Hydraulics, Nuclear Energy and Safety Department, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Andreani, Michele; Zboray, Robert; Dreier, Joerg [Laboratory for Thermal-Hydraulics, Nuclear Energy and Safety Department, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer The SETH-2 PANDA tests have supplied data with CFD-grade on plumes and jets at large-scale. Black-Right-Pointing-Pointer The PANDA tests have contributed to the understanding of phenomena with high safety relevance for LWRs. Black-Right-Pointing-Pointer The analytical activities related increased confidence in the use of various computational tools for safety analysis. - Abstract: The large-scale, multi-compartment PANDA facility (located at PSI in Switzerland) is one of the state-of-the-art facilities which is continuously upgraded to progressively match the requirements of CFD-grade experiments. Within the OECD/SETH projects, the PANDA facility has been used for the creation of an experimental database on basic containment phenomena e.g. gas mixing, transport, stratification, condensation. In the PANDA tests, these phenomena are driven by large scale plumes or jets. In the paper is presented a selection of the SETH PANDA experimental results. Examples of analytical activities performed at PSI using the GOTHIC, CFX-4 and CFX-5 codes will be used to illustrate how the spatial and temporal resolutions of the measurement grid in PANDA tests are adequate for CFD code (and advanced containment codes) assessment and validation purposes.

  7. Relaxation phenomena in rubber/layered silicate nanocomposites

    Directory of Open Access Journals (Sweden)

    2007-12-01

    Full Text Available Broadband Dielectric Spectroscopy (BDS is employed in order to investigate relaxation phenomena occurring in natural rubber (NR, polyurethane rubber (PUR and PUR/NR blend based nanocomposites, reinforced by 10 parts per hundred (phr Layered Silicates (LS. Nanocomposites and matrices were examined under identical conditions in a wide frequency (10–1 to 106 Hz and temperature (–100 to 50°C range. Experimental data are analyzed in terms of electric modulus formalism. The recorded relaxation phenomena include contributions from both the polymer matrices and the nanofiller. Natural rubber is a non-polar material and its performance is only slightly affected by the presence of layered silicates. Polyurethane rubber exhibits four distinct relaxation processes attributed, with ascending relaxation rate, to Interfacial Polarization (IP, glass/rubber transition (α-mode, local motions of polar side groups and small segments of the polymer chain (β, γ-mode. The same processes have been detected in all systems containing PUR. IP is present in all nanocomposites being the slowest recorded process. Finally, pronounced interfacial relaxation phenomena, occurring in the PUR+10 phr LS spectra, are attributed to nanoscale effects of intercalation and exfoliation.

  8. The Albanian Brain Drain phenomena and the Brain Gain strategy

    Directory of Open Access Journals (Sweden)

    Arta Musaraj

    2011-06-01

    Full Text Available Qualitative human resources remain one of the main problem of Eastern Europe and in particular Western Balkan countries. After 20 years of deep economic, political and social transformation, those countries are facing the problem of the highly qualified human resources they lost in these two decades, while in most of cases there is no a real measurement of the weight and impact these phenomena of Brain Drain has in the quality of the work force. Most of them are trying to set up and apply Brain Gain strategies at a national level. The paper aims to analyze and evaluate the influence that the missing of a previous qualitative and quantitative evaluation of the Phenomena of Brain Drain in Albania, has in the successful application of the Brain Gain strategy. The research objective will be fulfilled by analyzing the evolution of the Brain Drain phenomena, by an introduction of the Albanian characteristic and shape of  Brain Drain from 1990, by analyzing the Brain Gain strategy applied in the country comparing it to a successful application. The paper analyzes factors and variables which may affect the successful application of Brain Gain in Albania while  evidences the importance of stakeholder approach in objectives and aims of Brain Gain program and strategy and the use of the  Balance Scorecard as a strategic management system in “brain gain” strategy set up and application in the case of Albania and those of other countries of the region as well.

  9. Study Of The Fundamental Physical Principles in Atmospheric Modeling Based On Identification Of Atmosphere - Climate Control Factors: Bromine Explosion At The Polar Arctic Sunrise

    OpenAIRE

    Iudin, M.

    2007-01-01

    We attempt is to provide accumulated evidence and qualitative understanding of the associated atmospheric phenomena of the Arctic bromine explosion and their role in the functioning of the biotic Earth. We rationalize the empirical expression of the bromine influx into atmospheric boundary layer and calculate total amounts of the tropospheric BrO and Bry of the Arctic origin. Based on the quantities and partitioning of the reactive bromine species, we estimate the biogeochemical parametric co...

  10. Atmospheric refractivity effects on mid-infrared ELT adaptive optics

    CERN Document Server

    Kendrew, S; Mathar, R J; Stuik, R; Hippler, S; Brandl, B

    2008-01-01

    We discuss the effect of atmospheric dispersion on the performance of a mid-infrared adaptive optics assisted instrument on an extremely large telescope (ELT). Dispersion and atmospheric chromaticity is generally considered to be negligible in this wavelength regime. It is shown here, however, that with the much-reduced diffraction limit size on an ELT and the need for diffraction-limited performance, refractivity phenomena should be carefully considered in the design and operation of such an instrument. We include an overview of the theory of refractivity, and the influence of infrared resonances caused by the presence of water vapour and other constituents in the atmosphere. `Traditional' atmospheric dispersion is likely to cause a loss of Strehl only at the shortest wavelengths (L-band). A more likely source of error is the difference in wavelengths at which the wavefront is sensed and corrected, leading to pointing offsets between wavefront sensor and science instrument that evolve with time over a long e...

  11. On the ethical-aesthetic potentials of special atmospheres

    Directory of Open Access Journals (Sweden)

    Andreas Rauh

    2014-07-01

    Full Text Available Discussions concerning the atmospheric raise questions about how it can be defined and what influences may stem from particular atmospheres. Moreover, a shift in emphasis can be seen in respect of the way phenomena and disciplines are understood. Aesthetics is considered to be a theory of sensual perception; ethics serves as a theory of the good life. The article focuses on the relationship between atmospheres and aesthetics (e.g. Benjamin’s ‘aura’ and Rilke on Rodin’s sculptures as well as atmospheres and ethics (e.g. architecture or politics as façade and concludes with three points about ethical-aesthetic potentials, thus enhancing in-betweenness, the development of aesthetic interest, as well as a re-evaluation.

  12. An Atmospheric Science Observing System Simulation Experiment (OSSE) Environment

    Science.gov (United States)

    Lee, Meemong; Weidner, Richard; Qu, Zheng; Bowman, Kevin; Eldering, Annmarie

    2010-01-01

    An atmospheric sounding mission starts with a wide range of concept designs involving measurement technologies, observing platforms, and observation scenarios. Observing system simulation experiment (OSSE) is a technical approach to evaluate the relative merits of mission and instrument concepts. At Jet Propulsion Laboratory (JPL), the OSSE team has developed an OSSE environment that allows atmospheric scientists to systematically explore a wide range of mission and instrument concepts and formulate a science traceability matrix with a quantitative science impact analysis. The OSSE environment virtually creates a multi-platform atmospheric sounding testbed (MAST) by integrating atmospheric phenomena models, forward modeling methods, and inverse modeling methods. The MAST performs OSSEs in four loosely coupled processes, observation scenario exploration, measurement quality exploration, measurement quality evaluation, and science impact analysis.

  13. Lower Atmospheric Boundary Layer Experiment (LABLE) Final Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Klein, P [University of Oklahoma - School of Meteorology; Bonin, TA; Newman, JF [National Renewable Energy Laboratory; Turner, DD [National Oceanic and Atmospheric Administration; Chilson, P [University of Oklahoma; Blumberg, WG [University of Oklahoma; Mishra, S; Wainwright, CE; Carney, M [University of Oklahoma - School of Meteorology; Jacobsen, EP [University of Oklahoma; Wharton, S [Lawrence Livermore National Laboratory

    2015-11-01

    The Lower Atmospheric Boundary Layer Experiment (LABLE) included two measurement campaigns conducted at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site in Oklahoma during 2012 and 2013. LABLE was designed as a multi-phase, low-cost collaboration among the University of Oklahoma, the National Severe Storms Laboratory, Lawrence Livermore National Laboratory, and the ARM program. A unique aspect was the role of graduate students in LABLE. They served as principal investigators and took the lead in designing and conducting experiments using different sampling strategies to best resolve boundary-layer phenomena.

  14. Aviation Safety Program Atmospheric Environment Safety Technologies (AEST) Project

    Science.gov (United States)

    Colantonio, Ron

    2011-01-01

    Engine Icing: Characterization and Simulation Capability: Develop knowledge bases, analysis methods, and simulation tools needed to address the problem of engine icing; in particular, ice-crystal icing Airframe Icing Simulation and Engineering Tool Capability: Develop and demonstrate 3-D capability to simulate and model airframe ice accretion and related aerodynamic performance degradation for current and future aircraft configurations in an expanded icing environment that includes freezing drizzle/rain Atmospheric Hazard Sensing and Mitigation Technology Capability: Improve and expand remote sensing and mitigation of hazardous atmospheric environments and phenomena

  15. ARISK PHENOMENA IN THE SILVANIA MOUNTAINS, INTUITIVE AND GENETIC REFLEXES

    Directory of Open Access Journals (Sweden)

    CAMELIA BOGDAN

    2014-05-01

    Full Text Available Risk phenomena in the Silvania Mountains, intuitive and genetic reflexes. In the contemporary period, the scientific research under the auspices of the global development has experienced a real quantitative and qualitative revolution. Theoretically and methodologically, the widespread promotion of the “concept of discontinuity” in terms of content, significances, manifestation, implications is observed, which has become a new imperative of the nowadays geography. The phenomena of discontinuity happen as real “paroxysmal, rhythm and intensity ruptures“ in relation to the normal occurrence defined either through the average value, determined on statistical basis as hydrological, meteorological, climatic phenomena or in discrete forms, when the phenomena occur in a veiled manner and they are perceptible only through their effects, respectively the environmental reflexes. Among the notions used with reference to extreme evolutionary discontinuities, we quote: the hazard, the disaster, the calamity and the risk to which was added a series of related notions: stability, sensitivity, resilience, fragility and vulnerability. The Silvania Mountains, a representative territorial unit within Silvania Land, with a fascinating and controversial geological origin, a real petrographic synthesis with uncovered crystalline stone, brought to the surface due to erosion under the layers of Neogene sediments, as a last remaining of a grandiose Hercynian chain with a varied orientation SW-NE of which were part the Massif Central –France, the east side, the Vosges Mountains, the Black Forest Mountains, the Harz Mountains and Bohemia. In this range of mountains, we also mention the Silvania Hercynian Mountains, respectively Plopiș and Meseș Mountains.This mountainous elevation level has an important role within the landscape as "geographical discontinuity factor” on one hand, between the Someșan Plateau and the Silvania piedmontan hills (Meseș Mountains

  16. Numerical Simulation of Low Mach Number Fluid - Phenomena.

    Science.gov (United States)

    Reitsma, Scott H.

    A method for the numerical simulation of low Mach number (M) fluid-acoustic phenomena is developed. This computational fluid-acoustic (CFA) methodology is based upon a set of conservation equations, termed finite-compressible, derived from the unsteady Navier-Stokes equations. The finite-compressible and more familiar pseudo-compressible equations are compared. The impact of derivation assumptions are examined theoretically and through numerical experimentation. The error associated with these simplifications is shown to be of O(M) and proportional to the amplitude of unsteady phenomena. A computer code for the solution of the finite -compressible equations is developed from an existing pseudo -compressible code. Spatial and temporal discretization issues relevant in the context of near field fluid-acoustic simulations are discussed. The finite volume code employs a MUSCL based third order upwind biased flux difference splitting algorithm for the convective terms. An explicit, three stage, second order Runge-Kutta temporal integration is employed for time accurate simulations while an implicit, approximately factored time quadrature is available for steady state convergence acceleration. The CFA methodology is tested in a series of problems which examine the appropriateness of the governing equations, the exacerbation of spatial truncation errors and the degree of temporal accuracy. Characteristic based boundary conditions employing a spatial formulation are developed. An original non-reflective boundary condition based upon the generalization and extension of existing methods is derived and tested in a series of multi-dimensional problems including those involving viscous shear flows and propagating waves. The final numerical experiment is the simulation of boundary layer receptivity to acoustic disturbances. This represents the first simulation of receptivity at a surface inhomogeneity in which the acoustic phenomena is modeled using physically appropriate

  17. ASIRI: Remote Sensing of Atmospheric Waves and Instabilities (RAWI)

    Science.gov (United States)

    2015-09-30

    packets in the atmosphere and the seasonally reversing current systems and upwelling in the ocean, all of them are strongly coupled. It is...occurs over a continuum of scales, from regional-scale heat transport by the (occasionally reversing ) Walker circulation down to local heat fluxes...to Kelvin wave propagation in the equatorial IO, MJO and other subseasonal phenomena. Given the logistical 2 and financial constraints, the

  18. Atmospheric Habitable Zones in Y Dwarf Atmospheres

    CERN Document Server

    Yates, Jack S; Biller, Beth; Cockell, Charles S

    2016-01-01

    We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. We illustrate this idea using the object WISE J085510.83-0714442.5, which is a cool, free-floating brown dwarf. We allow organisms to adapt to their atmospheric environment (described by temperature, convection, and gravity) by adopting different growth strategies that maximize their chance of survival and proliferation. We assume a constant upward vertical velocity through the AHZ. We found that the organism growth strategy is most sensitive to the magnitude of the atmospheric convection. Stronger convection supports the evolution of more massive organisms. For a purely radiative environment we find that evolved organisms have a mass that is an order of magnitude smaller than terrestrial microbes, thereby defining a dynamical constraint on the dimensions of life that an AHZ can support. Ba...

  19. Measurement of the Atmospheric $\

    CERN Document Server

    Aartsen, M G; Abdou, Y; Ackermann, M; Adams, J; Aguilar, J A; Ahlers, M; Altmann, D; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Baum, V; Bay, R; Beattie, K; Beatty, J J; Bechet, S; Tjus, J Becker; Becker, K -H; Bell, M; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohaichuk, S; Bohm, C; Bose1, D; Boser, S; Botner, O; Brayeur, L; Brown, A M; Bruijn, R; Brunner, J; Buitink, S; Carson, M; Casey, J; Casier, M; Chirkin, D; Christy, B; Clark, K; Clevermann, F; Cohen, S; Cowen, D F; Silva, A H Cruz; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; De Ridder, S; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Diaz-Velez, J C; Dreyer, J; Dumm, J P; Dunkman, M; Eagan, R; Eberhardt, B; Eisch, J; Ellsworth, R W; Engdegard, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Flis, S; Franckowiak, A; Franke, R; Frantzen, K; Fuchs, T; Gaisser, T K; Gallagher, J; Gerhardt, L; Gladstone, L; Glusenkamp, T; Goldschmidt, A; Golup, G; Goodman, J A; Gora, D; Grant, D; Gross, A; Grullon, S; Gurtner, M; Ha, C; Ismail, A Haj; Hallgren, A; Halzen, F; Hanson, K; Heereman, D; Heimann, P; Heinen, D; Helbing, K; Hellauer, R; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, R; Homeier, A; Hoshina, K; Huelsnitz, W; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Japaridze, G S; Jlelati, O; Kappes, A; Karg, T; Karle, A; Kiryluk, J; Kislat, F; Klas, J; Klein, S R; Kohne, J -H; Kohnen, G; Kolanoski, H; Kopke, L; Kopper, C; Kopper, S; Koskinen, D J; Kowalski, M; Krasberg, M; Kroll, G; Kunnen, J; Kurahashi, N; Kuwabara, T; Labare, M; Landsman, H; Larson, M J; Lauer, R; Lesiak-Bzdak, M; Lunemann, J; Madsen, J; Maruyama, R; Mase, K; Matis, H S; McNally, F; Meagher, K; Merck, M; Meszaros, P; Meures, T; Miarecki, S; Middell, E; Milke, N; Miller, J; Mohrmann, L; Montaruli, T; Morse, R; Nahnhauer, R; Naumann, U; Nowicki, S C; Nygren, D R; Obertacke, A; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Panknin, S; Paul, L; Pepper, J A; Heros, C Perez de los; Pieloth, D; Pirk, N; Posselt, J; Price, P B; Przybylski, G T; Radel, L; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Richman, M; Riedel, B; Rodrigues, J P; Rott, C; Ruhe, T; Ruzybayev, B; Ryckbosch, D; Saba, S M; Salameh, T; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Scheel, M; Scheriau, F; Schmidt, T; Schmitz, M; Schoenen, S; Schoneberg, S; Schonherr, L; Schonwald, A; Schukraft, A; Schulte, L; Schulz, O; Seckel, D; Seo, S H; Sestayo, Y; Seunarine, S; Sheremata, C; Smith, M W E; Soiron, M; Soldin, D; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stasik, A; Stezelberger, T; Stokstad, R G; Stoss, A; Strahler, E A; Strom, R; Sullivan, G W; Taavola, H; Taboada, I; Tamburro, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Usner, M; van der Drift, D; van Eijndhoven, N; Van Overloop, A; van Santen, J; Vehring, M; Voge1, M; Vraeghe, M; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Wasserman, R; Weaver, Ch; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wissing, H; Wolf, M; Wood, T R; Woschnagg, K; Xu, C; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Ziemann, J; Zierke, S; Zilles, A; Zoll, M

    2012-01-01

    We report the first observation in a high energy neutrino telescope of cascades induced by atmospheric electron neutrinos and by neutral current interactions of atmospheric neutrinos of all flavors. Using data recorded during the first year of operation of IceCube's DeepCore low energy extension, a sample of 1029 events is observed in 281 days of data. The number of observed cascades is $N_{\\rm cascade} = 496 \\pm 66 (stat.) \\pm 88(syst.)$ and the rest of the sample consists of residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muon neutrinos. The flux of the atmospheric electron neutrinos is determined in the energy range between approximately 80 GeV and 6 TeV and is consistent with models of atmospheric neutrinos.

  20. Atmospheric Circulation of Exoplanets

    CERN Document Server

    Showman, Adam P; Menou, Kristen

    2009-01-01

    We survey the basic principles of atmospheric dynamics relevant to explaining existing and future observations of exoplanets, both gas giant and terrestrial. Given the paucity of data on exoplanet atmospheres, our approach is to emphasize fundamental principles and insights gained from Solar-System studies that are likely to be generalizable to exoplanets. We begin by presenting the hierarchy of basic equations used in atmospheric dynamics, including the Navier-Stokes, primitive, shallow-water, and two-dimensional nondivergent models. We then survey key concepts in atmospheric dynamics, including the importance of planetary rotation, the concept of balance, and scaling arguments to show how turbulent interactions generally produce large-scale east-west banding on rotating planets. We next turn to issues specific to giant planets, including their expected interior and atmospheric thermal structures, the implications for their wind patterns, and mechanisms to pump their east-west jets. Hot Jupiter atmospheric d...

  1. Development of a preliminary PIRT (Phenomena Identification and Ranking Table) of thermal-hydraulic phenomena for SMART

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Bub Dong; Lee, Won Jae; Kim, Hee Cheol; Song, Jin Ho; Sim, Suk Ku [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    The work reported in this paper identifies the thermal-hydraulic phenomena that are expected to occur during a number of key transients in SMART (System-integrated Modular Advanced ReacTor) which is under development at KAERI. The result of this effort is based on the current design concept of SMART integral reactor. Although the design is still evolving, the preliminary Phenomena Identification and Ranking Table (PIRT) has been developed based on the experts` knowledge and experience. The preliminary PIRT has been developed by consensus of KAERI expert panelists and AHP (Analytical Hierarchy Process). Preliminary PIRT developed in this paper is intended to be used to identify and integrate development areas of further experimental tests needed, thermal hydraulic models and correlations and code improvements for the safety analysis of the SMART. 8 refs., 4 tabs (Author)

  2. Atmospheric Measurements Laboratory (AML)

    Data.gov (United States)

    Federal Laboratory Consortium — The Atmospheric Measurements Laboratory (AML) is one of the nation's leading research facilities for understanding aerosols, clouds, and their interactions. The AML...

  3. The Mars atmosphere as seen from Curiosity

    Science.gov (United States)

    Mischna, Michael

    Study of the Mars atmosphere by the Mars Science Laboratory (MSL) has been ongoing since immediately after landing on August 6, 2012 (UTC) at the bottom of Gale Crater. The MSL Rover Environmental Monitoring Station (REMS) has been the primary payload for atmospheric monitoring, while additional observations from the ChemCam, Mastcam, Navcam and Sample Analysis at Mars (SAM) instruments have augmented our understanding of the local martian environment at Gale. The REMS instrument consists of six separate sensor types, observing air and ground temperature, near-surface winds, relative humidity, surface pressure and UV radiation. The standard cadence of REMS observations consists of five-minute observations of 1 Hz frequency at the top of each hour, augmented by several one-hour “extended blocks” each sol, also at 1 Hz frequency, together yielding one of the most richly diverse and detailed samplings of the martian atmosphere. Among the intriguing atmospheric phenomena observed during the first 359 sols of the mission is a substantially greater (˜12% of the diurnal mean) diurnal pressure cycle than found in previous surface measurements by Viking at a similar season (˜3-4%), likely due to the topography of the crater environment. Measurements of air and ground temperature by REMS are seen to reflect both changes in atmospheric opacity as well as transitions in the surface geology (and surface thermal properties) along the rover’s traverse. The REMS UV sensor has provided the first measurements of ultraviolet flux at the martian surface, and identified dust events that reduce solar insolation at the surface. The REMS RH sensor has observed a seasonal change in humidity in addition to the expected diurnal variations in relative humidity; however, no surface frost has been detected through the first 360 sols of the mission. With a weekly cadence, Navcam images the local zenith for purposes of tracking cloud motion and wind direction, and likewise observes the

  4. Effect of atmospheric environment on the attenuation coefficient of light in water

    CERN Document Server

    Liu, Juan; Tang, Yijun; Zhu, Kaixing; Ge, Yuan; Chen, Xuegang; He, Xingdao; Liu, Dahe

    2014-01-01

    The attenuation coefficient of 532 nm light in water under different atmospheric conditions was investigated. Measurements were made over a two-year period at the same location and show that the attenuation coefficient is significantly influenced by the atmospheric environment. It is lowest when the atmospheric pressure is high and temperature is low, and is highest when the atmospheric pressure is low and temperature is high. The maximum attenuation coefficient of pure water in these studies was about three times the minimum value. The mechanism of the phenomena is discussed. These results are also important in underwater acoustics.

  5. Geospatial Predictive Modelling for Climate Mapping of Selected Severe Weather Phenomena Over Poland: A Methodological Approach

    Science.gov (United States)

    Walawender, Ewelina; Walawender, Jakub P.; Ustrnul, Zbigniew

    2017-02-01

    The main purpose of the study is to introduce methods for mapping the spatial distribution of the occurrence of selected atmospheric phenomena (thunderstorms, fog, glaze and rime) over Poland from 1966 to 2010 (45 years). Limited in situ observations as well the discontinuous and location-dependent nature of these phenomena make traditional interpolation inappropriate. Spatially continuous maps were created with the use of geospatial predictive modelling techniques. For each given phenomenon, an algorithm identifying its favourable meteorological and environmental conditions was created on the basis of observations recorded at 61 weather stations in Poland. Annual frequency maps presenting the probability of a day with a thunderstorm, fog, glaze or rime were created with the use of a modelled, gridded dataset by implementing predefined algorithms. Relevant explanatory variables were derived from NCEP/NCAR reanalysis and downscaled with the use of a Regional Climate Model. The resulting maps of favourable meteorological conditions were found to be valuable and representative on the country scale but at different correlation ( r) strength against in situ data (from r = 0.84 for thunderstorms to r = 0.15 for fog). A weak correlation between gridded estimates of fog occurrence and observations data indicated the very local nature of this phenomenon. For this reason, additional environmental predictors of fog occurrence were also examined. Topographic parameters derived from the SRTM elevation model and reclassified CORINE Land Cover data were used as the external, explanatory variables for the multiple linear regression kriging used to obtain the final map. The regression model explained 89 % of annual frequency of fog variability in the study area. Regression residuals were interpolated via simple kriging.

  6. Finite-difference numerical modelling of gravito-acoustic wave propagation in a windy and attenuating atmosphere

    OpenAIRE

    2016-01-01

    in press; International audience; Acoustic and gravity waves propagating in planetary atmospheres have been studied intensively as markers of specific phenomena such as tectonic events or explosions or as contributors to atmosphere dynamics. To get a better understanding of the physics behind these dynamic processes, both acoustic and gravity waves propagation should be modelled in a 3D attenuating and windy atmosphere extending from the ground to the upper thermosphere. Thus, in order to pro...

  7. Space Commercial Opportunities for Fluid Physics and Transport Phenomena Applications

    Science.gov (United States)

    Gavert, R.

    2000-01-01

    Microgravity research at NASA has been an undertaking that has included both science and commercial approaches since the late 80s and early 90s. The Fluid Physics and Transport Phenomena community has been developed, through NASA's science grants, into a valuable base of expertise in microgravity science. This was achieved through both ground and flight scientific research. Commercial microgravity research has been primarily promoted thorough NASA sponsored Centers for Space Commercialization which develop cost sharing partnerships with industry. As an example, the Center for Advanced Microgravity Materials Processing (CAMMP)at Northeastern University has been working with cost sharing industry partners in developing Zeolites and zeo-type materials as an efficient storage medium for hydrogen fuel. Greater commercial interest is emerging. The U.S. Congress has passed the Commercial Space Act of 1998 to encourage the development of a commercial space industry in the United States. The Act has provisions for the commercialization of the International Space Station (ISS). Increased efforts have been made by NASA to enable industrial ventures on-board the ISS. A Web site has been established at http://commercial/nasa/gov which includes two important special announcements. One is an open request for entrepreneurial offers related to the commercial development and use of the ISS. The second is a price structure and schedule for U.S. resources and accommodations. The purpose of the presentation is to make the Fluid Physics and Transport Phenomena community, which understands the importance of microgravity experimentation, aware of important aspects of ISS commercial development. It is a desire that this awareness will be translated into a recognition of Fluid Physics and Transport Phenomena application opportunities coordinated through the broad contacts of this community with industry.

  8. Physics-based prognostic modelling of filter clogging phenomena

    Science.gov (United States)

    Eker, Omer F.; Camci, Fatih; Jennions, Ian K.

    2016-06-01

    In industry, contaminant filtration is a common process to achieve a desired level of purification, since contaminants in liquids such as fuel may lead to performance drop and rapid wear propagation. Generally, clogging of filter phenomena is the primary failure mode leading to the replacement or cleansing of filter. Cascading failures and weak performance of the system are the unfortunate outcomes due to a clogged filter. Even though filtration and clogging phenomena and their effects of several observable parameters have been studied for quite some time in the literature, progression of clogging and its use for prognostics purposes have not been addressed yet. In this work, a physics based clogging progression model is presented. The proposed model that bases on a well-known pressure drop equation is able to model three phases of the clogging phenomena, last of which has not been modelled in the literature yet. In addition, the presented model is integrated with particle filters to predict the future clogging levels and to estimate the remaining useful life of fuel filters. The presented model has been implemented on the data collected from an experimental rig in the lab environment. In the rig, pressure drop across the filter, flow rate, and filter mesh images are recorded throughout the accelerated degradation experiments. The presented physics based model has been applied to the data obtained from the rig. The remaining useful lives of the filters used in the experimental rig have been reported in the paper. The results show that the presented methodology provides significantly accurate and precise prognostic results.

  9. Modelling transport phenomena in a multi-physics context

    Energy Technology Data Exchange (ETDEWEB)

    Marra, Francesco [Dipartimento di Ingegneria Chimica e Alimentare - Università degli studi di Salerno Via Ponte Don Melillo - 84084 Fisciano SA (Italy)

    2015-01-22

    Innovative heating research on cooking, pasteurization/sterilization, defrosting, thawing and drying, often focuses on areas which include the assessment of processing time, evaluation of heating uniformity, studying the impact on quality attributes of the final product as well as considering the energy efficiency of these heating processes. During the last twenty years, so-called electro-heating-processes (radio-frequency - RF, microwaves - MW and ohmic - OH) gained a wide interest in industrial food processing and many applications using the above mentioned technologies have been developed with the aim of reducing processing time, improving process efficiency and, in many cases, the heating uniformity. In the area of innovative heating, electro-heating accounts for a considerable portion of both the scientific literature and commercial applications, which can be subdivided into either direct electro-heating (as in the case of OH heating) where electrical current is applied directly to the food or indirect electro-heating (e.g. MW and RF heating) where the electrical energy is firstly converted to electromagnetic radiation which subsequently generates heat within a product. New software packages, which make easier solution of PDEs based mathematical models, and new computers, capable of larger RAM and more efficient CPU performances, allowed an increasing interest about modelling transport phenomena in systems and processes - as the ones encountered in food processing - that can be complex in terms of geometry, composition, boundary conditions but also - as in the case of electro-heating assisted applications - in terms of interaction with other physical phenomena such as displacement of electric or magnetic field. This paper deals with the description of approaches used in modelling transport phenomena in a multi-physics context such as RF, MW and OH assisted heating.

  10. Modelling transport phenomena in a multi-physics context

    Science.gov (United States)

    Marra, Francesco

    2015-01-01

    Innovative heating research on cooking, pasteurization/sterilization, defrosting, thawing and drying, often focuses on areas which include the assessment of processing time, evaluation of heating uniformity, studying the impact on quality attributes of the final product as well as considering the energy efficiency of these heating processes. During the last twenty years, so-called electro-heating-processes (radio-frequency - RF, microwaves - MW and ohmic - OH) gained a wide interest in industrial food processing and many applications using the above mentioned technologies have been developed with the aim of reducing processing time, improving process efficiency and, in many cases, the heating uniformity. In the area of innovative heating, electro-heating accounts for a considerable portion of both the scientific literature and commercial applications, which can be subdivided into either direct electro-heating (as in the case of OH heating) where electrical current is applied directly to the food or indirect electro-heating (e.g. MW and RF heating) where the electrical energy is firstly converted to electromagnetic radiation which subsequently generates heat within a product. New software packages, which make easier solution of PDEs based mathematical models, and new computers, capable of larger RAM and more efficient CPU performances, allowed an increasing interest about modelling transport phenomena in systems and processes - as the ones encountered in food processing - that can be complex in terms of geometry, composition, boundary conditions but also - as in the case of electro-heating assisted applications - in terms of interaction with other physical phenomena such as displacement of electric or magnetic field. This paper deals with the description of approaches used in modelling transport phenomena in a multi-physics context such as RF, MW and OH assisted heating.

  11. Designing Dynamic Atmospheres

    DEFF Research Database (Denmark)

    Højlund, Marie; Kinch, Sofie

    2012-01-01

    This paper addresses the notion of atmospheres from a designerly perspective, and discusses temporal challenges facing interaction designers when acknowledging the dynamic character of it. As atmospheres are created in the relation between body, space, and time, a pragmatic approach seems useful...

  12. Proterozoic atmospheric oxygen

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene

    2014-01-01

    This article is concerned with the evolution of atmospheric oxygen concentrations through the Proterozoic Eon. In particular, this article will seek to place the history of atmospheric oxygenation through the Proterozoic Eon in the context of the evolving physical environment including the histor...

  13. Clouds in Planetary Atmospheres

    Science.gov (United States)

    West, R.; Murdin, P.

    2000-11-01

    What are clouds? The answer to that question is both obvious and subtle. In the terrestrial atmosphere clouds are familiar as vast collections of small water drops or ice crystals suspended in the air. In the atmospheres of Venus, Mars, Jupiter, Saturn, Saturn's moon Titan, Uranus, Neptune, and possibly Pluto, they are composed of several other substances including sulfuric acid, ammonia, hydroge...

  14. A review of experimental investigations on thermal phenomena in nanofluids.

    Science.gov (United States)

    Thomas, Shijo; Balakrishna Panicker Sobhan, Choondal

    2011-05-09

    Nanoparticle suspensions (nanofluids) have been recommended as a promising option for various engineering applications, due to the observed enhancement of thermophysical properties and improvement in the effectiveness of thermal phenomena. A number of investigations have been reported in the recent past, in order to quantify the thermo-fluidic behavior of nanofluids. This review is focused on examining and comparing the measurements of convective heat transfer and phase change in nanofluids, with an emphasis on the experimental techniques employed to measure the effective thermal conductivity, as well as to characterize the thermal performance of systems involving nanofluids.

  15. Some New Results From Applying Thermodynamics to Wetting Phenomena

    Directory of Open Access Journals (Sweden)

    Daniel Tondeur

    2008-06-01

    Full Text Available This contribution focuses on some non-classical aspects of capillary phenomena, mostly omitted in classical approaches, in particular the non-isothermal aspects. A systematic thermodynamic approach is proposed that allows a rigorous formulation of the governing equations in non-isothermal situations, by introducing the surface effects in the energy and entropy balances. The energetic quantities (work and heat are calculated in a number of examples, such as adiabatic and isothermal wetting/dewetting of a porous medium, nanofluids heating, emulsion split, and new equilibrium criteria are derived were appropriate.

  16. Numerical modeling to investigate slopes and mass flow phenomena

    Institute of Scientific and Technical Information of China (English)

    Heinz Konietzky; Lei NIE; Youhong SUN

    2006-01-01

    An overview is given about up-to-date techniques for slope stability and deformation analysis as well as mass flow phenomena simulation. The paper concentrates on a few aspects in respect to the use of numerical modeling techniques, especially in relation to the shear strength reduction techniques, discontinuum modeling, probabilistic concepts, the combination of GIS and numerical modeling as well as sophisticated hydro-mechanical coupling with time-dependent material behavior. At present these topics are preferred topics of scientific and technical research.

  17. Influences of weather phenomena on automotive laser radar systems

    Science.gov (United States)

    Rasshofer, R. H.; Spies, M.; Spies, H.

    2011-07-01

    Laser radar (lidar) sensors provide outstanding angular resolution along with highly accurate range measurements and thus they were proposed as a part of a high performance perception system for advanced driver assistant functions. Based on optical signal transmission and reception, laser radar systems are influenced by weather phenomena. This work provides an overview on the different physical principles responsible for laser radar signal disturbance and theoretical investigations for estimation of their influence. Finally, the transmission models are applied for signal generation in a newly developed laser radar target simulator providing - to our knowledge - worldwide first HIL test capability for automotive laser radar systems.

  18. Nanophenomena at surfaces fundamentals of exotic condensed matter phenomena

    CERN Document Server

    Michailov, Michail

    2011-01-01

    This book presents the state of the art in nanoscale surface physics. It outlines contemporary trends in the field covering a wide range of topical areas: atomic structure of surfaces and interfaces, molecular films and polymer adsorption, biologically inspired nanophysics, surface design and pattern formation, and computer modeling of interfacial phenomena. Bridging 'classical' and 'nano' concepts, the present volume brings attention to the physical background of exotic condensed-matter properties. The book is devoted to Iwan Stranski and Rostislaw Kaischew, remarkable scientists, who played

  19. Introduction to wave scattering, localization, and mesoscopic phenomena

    CERN Document Server

    Sheng, Ping

    1995-01-01

    This book gives readers a coherent picture of waves in disordered media, including multiple scattered waves. The book is intended to be self-contained, with illustrated problems and solutions at the end of each chapter to serve the double purpose of filling out the technical and mathematical details and giving the students exercises if used as a course textbook.The study of wave behavior in disordered media has applications in:Condensed matter physics (semi and superconductor nanostructures and mesoscopic phenomena)Materials science/analytical chemistry (analysis of composite and crystalline structures and properties)Optics and electronics (microelectronic and optoelectronic devices)Geology (seismic exploration of Earths subsurface)

  20. Thermomagnetic phenomena in the mixed state of high temperature superconductors

    Science.gov (United States)

    Meilikhov, E. Z.

    1995-01-01

    Galvano- and thermomagnetic-phenomena in high temperature superconductors, based on kinetic coefficients, are discussed, along with a connection between the electric field and the heat flow in superconductor mixed state. The relationship that determines the transport coefficients of high temperature superconductors in the mixed state based on Seebeck and Nernst effects is developed. It is shown that this relationship is true for a whole transition region of the resistive mixed state of a superconductor. Peltier, Ettingshausen and Righi-Leduc effects associated with heat conductivity as related to high temperature superconductors are also addressed.

  1. Analyzing simple pendulum phenomena with a smartphone acceleration sensor

    Science.gov (United States)

    Vogt, Patrik; Kuhn, Jochen

    2012-10-01

    This paper describes a further experiment using the acceleration sensor of a smartphone. For a previous column on this topic, including the description of the operation and use of the acceleration sensor, see Ref. 1. In this contribution we focus on analyzing simple pendulum phenomena. A smartphone is used as a pendulum bob, and SPARKvue2 software is used in conjunction with an iPhone or an iPod touch, or the Accelogger3 app for an Android device. As described in Ref. 1, the values measured by the smartphone are subsequently exported to a spreadsheet application (e.g., MS Excel) for analysis.

  2. Modeling of Multiscale and Multiphase Phenomena in Materials Processing

    Science.gov (United States)

    Ludwig, Andreas; Kharicha, Abdellah; Wu, Menghuai

    2013-03-01

    In order to demonstrate how CFD can help scientists and engineers to better understand the fundamentals of engineering processes, a number of examples are shown and discussed. The paper covers (i) special aspects of continuous casting of steel including turbulence, motion and entrapment of non-metallic inclusions, and impact of soft reduction; (ii) multiple flow phenomena and multiscale aspects during casting of large ingots including flow-induced columnar-to-equiaxed transition and 3D formation of channel segregation; (iii) multiphase magneto-hydrodynamics during electro-slag remelting; and (iv) melt flow and solidification of thin but large centrifugal castings.

  3. Quantum Simulator for Transport Phenomena in Fluid Flows

    CERN Document Server

    Mezzacapo, A; Lamata, L; Egusquiza, I L; Succi, S; Solano, E

    2015-01-01

    Transport phenomena are one of the most challenging problems in computational physics. We present a quantum simulator based on pseudospin-boson quantum systems, which is suitable for encoding fluid dynamics problems within a lattice kinetic formalism. This quantum simulator is obtained by exploiting the analogies between Dirac and lattice Boltzmann equations. It is shown that both the streaming and collision processes of lattice Boltzmann dynamics can be implemented with controlled quantum operations, using a heralded quantum protocol to encode non-unitary scattering processes. The proposed simulator is amenable to realization in controlled quantum platforms, such as ion-trap quantum computers or circuit quantum electrodynamics processors.

  4. Probing biological light-harvesting phenomena by optical cavities

    CERN Document Server

    Caruso, Filippo; Solano, Enrique; Huelga, Susana F; Aspuru-Guzik, Alán; Plenio, Martin B

    2011-01-01

    We propose a driven optical cavity quantum electrodynamics (QED) set up aimed at directly probing energy transport dynamics in photosynthetic biomolecules. We show that detailed information concerning energy transfer paths and delocalization of exciton states can be inferred (and exciton energies estimated) from the statistical properties of the emitted photons. This approach provides us with a novel spectroscopic tool for the interrogation of biological systems in terms of quantum optical phenomena which have been usually studied for atomic or solid-state systems, e.g. trapped atoms and semiconductor quantum dots.

  5. Nonlinear Phenomena in Buck-Boost Power Factor Correction Converter

    Directory of Open Access Journals (Sweden)

    Mehrnoosh Vatani

    2013-01-01

    Full Text Available Buck-Boost Power-Factor-Correction (PFC converter with Average-Current-Model (ACM control is a nonlinear circuit because of the multiplier using and large change in the duty cycle, so its stability analysis must be studied by nonlinear model. In this paper double averaging method is used for describing the model of this converter. By this model we would be able to explain the low frequency dynamics of the system and identify stability boundaries according to circuit parameters and also nonlinear phenomena of this converter are detected.

  6. Correlation between solar neutrino flux and other solar phenomena

    Science.gov (United States)

    Lal, S.; Subramanian, A.

    1985-01-01

    A study was made of the solar neutrino data with a tank of CC14 located 4800 mwe underground for the period 1970 to 83. These observations are on the production rates of Ar37 atoms via the reaction upsilon sub e + Cl37 yields Ar37 plus e(-) in the tank caused presumably by a flux of neutrinos from the Sun. The idea of possible time variations in the data shown is discussed and an attempt is made to correlate the variations to two other phenomena of solar origin-the sunspot number and the geomagnetic Ap index.

  7. Dynamic critical phenomena from spectral functions on the lattice

    CERN Document Server

    Berges, J; Sexty, D

    2009-01-01

    We investigate spectral functions in the vicinity of the critical temperature of a second-order phase transition. Since critical phenomena in quantum field theories are governed by classical dynamics, universal properties can be computed using real-time lattice simulations. For the example of a relativistic single-component scalar field theory in 2+1 dimensions, we compute the spectral function described by universal scaling functions and extract the dynamic critical exponent z. Together with exactly known static properties of this theory, we obtain a verification from first principles that the relativistic theory is well described by the dynamic universality class of relaxational models with conserved density (Model C).

  8. Human Mobility and Predictability enriched by Social Phenomena Information

    CERN Document Server

    Ponieman, Nicolas; Sarraute, Carlos

    2013-01-01

    The massive amounts of geolocation data collected from mobile phone records has sparked an ongoing effort to understand and predict the mobility patterns of human beings. In this work, we study the extent to which social phenomena are reflected in mobile phone data, focusing in particular in the cases of urban commute and major sports events. We illustrate how these events are reflected in the data, and show how information about the events can be used to improve predictability in a simple model for a mobile phone user's location.

  9. The Albanian Brain Drain phenomena and the Brain Gain strategy

    OpenAIRE

    Arta Musaraj

    2011-01-01

    Qualitative human resources remain one of the main problem of Eastern Europe and in particular Western Balkan countries. After 20 years of deep economic, political and social transformation, those countries are facing the problem of the highly qualified human resources they lost in these two decades, while in most of cases there is no a real measurement of the weight and impact these phenomena of Brain Drain has in the quality of the work force. Most of them are trying to set up and apply Bra...

  10. Astigmatism transfer phenomena in the optical parametric amplification process

    Science.gov (United States)

    Li, Wenkai; Chen, Yun; Li, Yanyan; Xu, Yi; Guo, Xiaoyang; Lu, Jun; Leng, Yuxin

    2017-01-01

    We numerically and experimentally investigate the astigmatism transfer phenomena in femtosecond optical parametric amplification (OPA). We model the OPA process based on the coupled second-order three-wave nonlinear propagation equations. The numerical and experimental results support that the input pump pulse astigmatism can be transferred into the idler pulse but not the signal pulse, and the idler pulse astigmatism originating from spatial walk-off is less than the idler pulse astigmatism received from the pump. Thus, we can provide a clear understanding of astigmatism transfer mechanisms in the OPA process, and make better use of broadband tunable OPA sources.

  11. Interfacial Phenomena: Linking Atomistic and Molecular Level Processes

    Energy Technology Data Exchange (ETDEWEB)

    Jay A Brandes

    2009-09-23

    This was a grant to support travel for scientists to present data and interact with others in their field. Specifically, speakers presented their data in a session entitled “Interfacial Phenomena: Linking Atomistic and Macroscopic Properties: Theoretical and Experimental Studies of the Structure and Reactivity of Mineral Surfaces”. The session ran across three ½ day periods, March 30-31 2004. The session’s organizers were David J. Wesolowski andGordon E. Brown Jr. There were a total of 30 talks presented.

  12. 78 FR 8202 - Meeting of the Joint ACRS Subcommittees on Thermal Hydraulic Phenomena and Materials, Metallurgy...

    Science.gov (United States)

    2013-02-05

    ... Hydraulic Phenomena and Materials, Metallurgy and Reactor Fuels; Notice of Meeting The Joint ACRS Subcommittees on Thermal Hydraulic Phenomena and Materials, Metallurgy and Reactor Fuels will hold a meeting...

  13. Emergent topological phenomena in thin films of pyrochlore iridates.

    Science.gov (United States)

    Yang, Bohm-Jung; Nagaosa, Naoto

    2014-06-20

    Because of the recent development of thin film and artificial superstructure growth techniques, it is possible to control the dimensionality of the system, smoothly between two and three dimensions. In this Letter we unveil the dimensional crossover of emergent topological phenomena in correlated topological materials. In particular, by focusing on the thin film of pyrochlore iridate antiferromagnets grown along the [111] direction, we demonstrate that the thin film can have a giant anomalous Hall conductance, proportional to the thickness of the film, even though there is no Hall effect in 3D bulk material. Moreover, in the case of ultrathin films, a quantized anomalous Hall conductance can be observed, despite the fact that the system is an antiferromagnet. In addition, we uncover the emergence of a new topological phase, the nontrivial topological properties of which are hidden in the bulk insulator and manifest only in thin films. This shows that the thin film of correlated topological materials is a new platform to search for unexplored novel topological phenomena.

  14. Selected social phenomena following the extraction of mineral resources

    Directory of Open Access Journals (Sweden)

    Kocoń Paweł

    2014-12-01

    Full Text Available The author, due to the didactic needs and seeing a small gap in the way of presenting scientific data on the area of social science, have decided to present this work hoping that it will influence on widening both the social science and geography knowledge of the recipients, having connected the development and creation of certain social phenomena with particular economic activity, that is, the extraction of mineral resources. The aim of the hereby text is to present such social phenomena like organizational culture, discourse and social capital. The notions mentioned above ought to concern not only students, but also the specialists and scientists dealing with any of those two fields, as it seems prudent to follow the path of closely connecting two major issues emerging from two distinctively separate areas of science if that may help to better understand how such mixture influence people’s behaviour and allows to draw conclusion on the effect such actions may have on community or society. Moreover, such fact was prior for the author to decide to work on the problem of protests for mining in the future. On the other hand, the article may help in organizing the process of exploitation of mineral resources in the different organizations involved in this type of activity.

  15. Emergent ultrafast phenomena in correlated oxides and heterostructures

    Science.gov (United States)

    Gandolfi, M.; Celardo, G. L.; Borgonovi, F.; Ferrini, G.; Avella, A.; Banfi, F.; Giannetti, C.

    2017-03-01

    The possibility of investigating the dynamics of solids on timescales faster than the thermalization of the internal degrees of freedom has disclosed novel non-equilibrium phenomena that have no counterpart at equilibrium. Transition metal oxides (TMOs) provide an interesting playground in which the correlations among the charges in the metal d-orbitals give rise to a wealth of intriguing electronic and thermodynamic properties involving the spin, charge, lattice and orbital orders. Furthermore, the physical properties of TMOs can be engineered at the atomic level, thus providing the platform to investigate the transport phenomena on timescales of the order of the intrinsic decoherence time of the charge excitations. Here, we review and discuss three paradigmatic examples of transient emerging properties that are expected to open new fields of research: (i) the creation of non-thermal magnetic states in spin–orbit Mott insulators; (ii) the possible exploitation of quantum paths for the transport and collection of charge excitations in heterostructures; (iii) the transient wave-like behavior of the temperature field in strongly anisotropic TMOs.

  16. Macroscopic Quantum Phenomena from the Correlation, Coupling and Criticality Perspectives

    Science.gov (United States)

    Chou, C. H.; Hu, B. L.; Subaşi, Y.

    2011-12-01

    In this sequel paper we explore how macroscopic quantum phenomena can be measured or understood from the behavior of quantum correlations which exist in a quantum system of many particles or components and how the interaction strengths change with energy or scale, under ordinary situations and when the system is near its critical point. We use the nPI (master) effective action related to the Boltzmann-BBGKY / Schwinger-Dyson hierarchy of equations as a tool for systemizing the contributions of higher order correlation functions to the dynamics of lower order correlation functions. Together with the large N expansion discussed in our first paper [1] we explore 1) the conditions whereby an H-theorem is obtained, which can be viewed as a signifier of the emergence of macroscopic behavior in the system. We give two more examples from past work: 2) the nonequilibrium dynamics of N atoms in an optical lattice under the large Script N (field components), 2PI and second order perturbative expansions, illustrating how N and Script N enter in these three aspects of quantum correlations, coherence and coupling strength. 3) the behavior of an interacting quantum system near its critical point, the effects of quantum and thermal fluctuations and the conditions under which the system manifests infrared dimensional reduction. We also discuss how the effective field theory concept bears on macroscopic quantum phenomena: the running of the coupling parameters with energy or scale imparts a dynamical-dependent and an interaction-sensitive definition of 'macroscopia'.

  17. GLASS MELTING PHENOMENA, THEIR ORDERING AND MELTING SPACE UTILISATION

    Directory of Open Access Journals (Sweden)

    Němec L.

    2013-12-01

    Full Text Available Four aspects of effective glass melting have been defined – namely the fast kinetics of partial melting phenomena, a consideration of the melting phenomena ordering, high utilisation of the melting space, and effective utilisation of the supplied energy. The relations were defined for the specific melting performance and specific energy consumption of the glass melting process which involve the four mentioned aspects of the process and indicate the potentials of effective melting. The quantity “space utilisation” has been treated in more detail as an aspect not considered in practice till this time. The space utilisation was quantitatively defined and its values have been determined for the industrial melting facility by mathematical modelling. The definitions of the specific melting performance and specific energy consumption have been used for assessment of the potential impact of a controlled melt flow and high space utilisation on the melting process efficiency on the industrial scale. The results have shown that even the partial control of the melt flow, leading to the partial increase of the space utilisation, may considerably increase the melting performance, whereas a decrease of the specific energy consumption was determined to be between 10 - 15 %.

  18. Possible regular phenomena in EXO 2030+375

    CERN Document Server

    Laplace, Eva; Moritani, Yuki; Nakajima, Motoki; Takagi, Toshihiro; Makishima, Kazuo; Santangelo, Andrea

    2016-01-01

    In the last 10 years, since its last giant outburst in 2006, regular X-ray outbursts (type I) were detected every periastron passage in the Be X-ray binary EXO 2030+375. Recently, however, it was reported that the source started to show a peculiar behavior: its X-ray flux decreased significantly and type I outbursts were missed in several cases. At the same time, the spin frequency of the neutron star, which had been increasing steadily since the end of the 2006 giant outburst, reached a plateau. Very recent observations indicate that the source is now starting to spin down. These observed phenomena have a striking similarity with those which took place 20 years ago, just before the source displayed a sudden orbital phase shift of the outburst peak (1995). This historical event occurred at the time exactly between the two giant outbursts (1985 and 2006). These phenomena suggest the system to have an underlying periodicity of 10.5 years between orbital phase shifts and/or giant outbursts. The suggested periodi...

  19. Initiating Young Children into Basic Astronomical Concepts and Phenomena

    Science.gov (United States)

    Kallery, M.

    2010-07-01

    In the present study we developed and implemented three units of activities aiming at acquainting very young children with basic astronomical concepts and phenomena such as the sphericity of the earth, the earth’s movements and the day/night cycle. The activities were developed by a group composed of a researcher/facilitator and six early-years teachers. In the activities children were presented with appropriate for their age scientific information along with conceptual tools such as a globe and an instructional video. Action research processes were used to optimize classroom practices and to gather useful information for the final shaping of the activities and the instruction materials. In these activities the adopted approach to learning can be characterized as socially constructed. The results indicated awareness of concepts and phenomena that the activities dealt with in high percentages of children, storage of the new knowledge in the long term memory and easy retrieval of it, and children’s enthusiasm for the subject.

  20. PREFACE: Physics and Mathematics of Nonlinear Phenomena 2013 (PMNP2013)

    Science.gov (United States)

    Konopelchenko, B. G.; Landolfi, G.; Martina, L.; Vitolo, R.

    2014-03-01

    Modern theory of nonlinear integrable equations is nowdays an important and effective tool of study for numerous nonlinear phenomena in various branches of physics from hydrodynamics and optics to quantum filed theory and gravity. It includes the study of nonlinear partial differential and discrete equations, regular and singular behaviour of their solutions, Hamitonian and bi- Hamitonian structures, their symmetries, associated deformations of algebraic and geometrical structures with applications to various models in physics and mathematics. The PMNP 2013 conference focused on recent advances and developments in Continuous and discrete, classical and quantum integrable systems Hamiltonian, critical and geometric structures of nonlinear integrable equations Integrable systems in quantum field theory and matrix models Models of nonlinear phenomena in physics Applications of nonlinear integrable systems in physics The Scientific Committee of the conference was formed by Francesco Calogero (University of Rome `La Sapienza', Italy) Boris A Dubrovin (SISSA, Italy) Yuji Kodama (Ohio State University, USA) Franco Magri (University of Milan `Bicocca', Italy) Vladimir E Zakharov (University of Arizona, USA, and Landau Institute for Theoretical Physics, Russia) The Organizing Committee: Boris G Konopelchenko, Giulio Landolfi, Luigi Martina, Department of Mathematics and Physics `E De Giorgi' and the Istituto Nazionale di Fisica Nucleare, and Raffaele Vitolo, Department of Mathematics and Physics `E De Giorgi'. A list of sponsors, speakers, talks, participants and the conference photograph are given in the PDF. Conference photograph

  1. A review of conduction phenomena in Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Park, Myounggu; Zhang, Xiangchun; Chung, Myoungdo; Less, Gregory B. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Sastry, Ann Marie [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Department of Material Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

    2010-12-15

    Conduction has been one of the main barriers to further improvements in Li-ion batteries and is expected to remain so for the foreseeable future. In an effort to gain a better understanding of the conduction phenomena in Li-ion batteries and enable breakthrough technologies, a comprehensive survey of conduction phenomena in all components of a Li-ion cell incorporating theoretical, experimental, and simulation studies, is presented here. Included are a survey of the fundamentals of electrical and ionic conduction theories; a survey of the critical results, issues and challenges with respect to ionic and electronic conduction in the cathode, anode and electrolyte; a review of the relationship between electrical and ionic conduction for three cathode materials: LiCoO{sub 2}, LiMn{sub 2}O{sub 4}, LiFePO{sub 4}; a discussion of phase change in graphitic anodes and how it relates to diffusivity and conductivity; and the key conduction issues with organic liquid, solid-state and ionic liquid electrolytes. (author)

  2. The fluid phenomena in the crystallization of the protein crystal

    Institute of Scientific and Technical Information of China (English)

    Duan Li; Kang Qi

    2008-01-01

    This paper reports that an optical diagnostic system consisting of Maeh-Zehnder interferometer with a phase shift device and image processor has been used for study of the kinetics of protein crystal growing process. The crystallization process of protein crystal by vapour diffusion is investigated. The interference fringes are observed in real time. The present experiment demonstrates that the diffusion and the sedimentation influence the crystallization of protein crystal which grows in solution, and the concentration capillary convection associated with surface tension occurs at the vicinity of free surface of the protein mother liquor, and directly affects on the outcome of protein crystallization. So far the detailed analysis and the important role of the fluid phenomena in protein crystallization have been discussed a little in both space- and ground-based crystal growth experiments. It is also found that these fluid phenomena affect theoutcome of protein crystallization, regular growth, and crystal quality. This may explain the fact that many results of space-based investigation do not show overall improvement.

  3. Containment atmosphere response to external sprays

    Energy Technology Data Exchange (ETDEWEB)

    Green, J.; Almenas, K. [Univ. of Maryland, College Park, MD (United States)

    1995-09-01

    The application of external sprays to a containment steel shell can be an effective energy removal method and has been proposed in the passive AP-600 design. Reduction of the steel shell temperature in contact with the containment atmosphere enhances both heat and mass transfer driving forces. Large scale experimental data in this area is scarce, therefore the measurements obtained from the E series tests conducted at the German HDR facility deserve special attention. These long term tests simulated various severe accident conditions, including external spraying of the hemispherical steel shell. This investigation focuses upon the integral response of the HDR containment atmosphere during spray periods and upon methods by which lumped parameter system codes, like CONTAIN, model the underlying condensation phenomena. Increases in spray water flowrates above a minimum value were ineffective at improving containment pressure reduction since the limiting resistance for energy transfer lies in the noncondensable-vapor boundary layer at the inner condensing surface. The spray created an unstable condition by cooling the upper layers of a heated atmosphere and thus inducing global natural circulation flows in the facility and subsequently, abrupt changes in lighter-than-air noncondensable (J{sub 2}/He) concentrations. Modeling results using the CONTAIN code are outlined and code limitations are delineated.

  4. Atmospheric composition change: Ecosystems–Atmosphere interactions

    DEFF Research Database (Denmark)

    Fowler, D.; Pilegaard, Kim; Sutton, M.A.

    2009-01-01

    and techniques in micrometeorology. For some of the compounds there have been paradigm shifts in approach and application of both techniques and assessment. These include flux measurements over marine surfaces and urban areas using micrometeorological methods and the up-scaling of flux measurements using...... in the size range 1 nm–10 μm including organic and inorganic chemical species. The main focus of the review is on the exchange between terrestrial ecosystems, both managed and natural and the atmosphere, although some new developments in ocean–atmosphere exchange are included. The material presented is biased...... towards the last decade, but includes earlier work, where more recent developments are limited or absent. New methodologies and instrumentation have enabled, if not driven technical advances in measurement. These developments have advanced the process understanding and upscaling of fluxes, especially...

  5. Glacial atmospheric phosphorus deposition

    Science.gov (United States)

    Kjær, Helle Astrid; Dallmayr, Remi; Gabrieli, Jacopo; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Svensson, Anders; Vallelonga, Paul

    2016-04-01

    Phosphorus in the atmosphere is poorly studied and thus not much is known about atmospheric phosphorus and phosphate transport and deposition changes over time, though it is well known that phosphorus can be a source of long-range nutrient transport, e.g. Saharan dust transported to the tropical forests of Brazil. In glacial times it has been speculated that transport of phosphorus from exposed shelves would increase the ocean productivity by wash out. However whether the exposed shelf would also increase the atmospheric load to more remote places has not been investigated. Polar ice cores offer a unique opportunity to study the atmospheric transport of aerosols on various timescales, from glacial-interglacial periods to recent anthropogenic influences. We have for the first time determined the atmospheric transport of phosphorus to the Arctic by means of ice core analysis. Both total and dissolved reactive phosphorus were measured to investigate current and past atmospheric transport of phosphorus to the Arctic. Results show that glacial cold stadials had increased atmospheric total phosphorus mass loads of 70 times higher than in the past century, while DRP was only increased by a factor of 14. In the recent period we find evidence of a phosphorus increase over the past 50 yrs in ice cores close to human occupation likely correlated to forest fires. References: Kjær, Helle Astrid, et al. "Continuous flow analysis method for determination of dissolved reactive phosphorus in ice cores." Environmental science & technology 47.21 (2013): 12325-12332. Kjær, Helle Astrid, et al. "Greenland ice cores constrain glacial atmospheric fluxes of phosphorus." Journal of Geophysical Research: Atmospheres120.20 (2015).

  6. The Role of Perspective Taking in How Children Connect Reference Frames When Explaining Astronomical Phenomena

    Science.gov (United States)

    Plummer, Julia D.; Bower, Corinne A.; Liben, Lynn S.

    2016-01-01

    This study investigates the role of perspective-taking skills in how children explain spatially complex astronomical phenomena. Explaining many astronomical phenomena, especially those studied in elementary and middle school, requires shifting between an Earth-based description of the phenomena and a space-based reference frame. We studied 7- to…

  7. Phenomena-based Process Synthesis and Design to achieve Process Intensification

    DEFF Research Database (Denmark)

    Lutze, Philip; Gani, Rafiqul; Woodley, John

    2011-01-01

    In order to improve processes incorporating process intensification and to allow them to go beyond pre-defined unit operations, the process has to be viewed at a lower level of aggregation, namely the phenomena scale. In this contribution, an approach for aggregating processes through phenomena...... level. This phenomena-based synthesis/design methodology is tested through a case study....

  8. Atmosphere beyond Poetics

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2014-01-01

    . In doing so, analysing the Crystal Palace – recognised as the epitome of controlled immersive experience as well as of atmospheric engineering (Sloterdijk 2008 (2005) – in parallel with other examples and theoretical explorations, will provide a canvas for discerning the means of creation of atmosphere...... Physical Presence in Space.” Oase #91, Building Atmosphere, 21-33 Sloterdijk, Peter. (2005) 2008. “The Crystal Palace.” Translated by Michael Darroch. Public 37: Public?, 12-15. Originally published in Peter Sloterdijk. Im Weltinnenraum des Kapitals: Für eine philoso-phische Theorie der Globalisierung, 265...

  9. The Fragility of Interdependency: Coupled Networks Switching Phenomena

    Science.gov (United States)

    Stanley, H. Eugene

    2013-03-01

    Recent disasters ranging from abrupt financial ``flash crashes'' and large-scale power outages to sudden death among the elderly dramatically exemplify the fact that the most dangerous vulnerability is hiding in the many interdependencies among different networks. In the past year, we have quantified failures in model of interconnected networks, and demonstrated the need to consider mutually dependent network properties in designing resilient systems. Specifically, we have uncovered new laws governing the nature of switching phenomena in coupled networks, and found that phenomena that are continuous ``second order'' phase transitions in isolated networks become discontinuous abrupt ``first order'' transitions in interdependent networks [S. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, and S. Havlin, ``Catastrophic Cascade of Failures in Interdependent Networks,'' Nature 464, 1025 (2010); J. Gao, S. V. Buldyrev, H. E. Stanley, and S. Havlin, ``Novel Behavior of Networks Formed from Interdependent Networks,'' Nature Physics 8, 40 (2012). We conclude by discussing the network basis for understanding sudden death in the elderly, and the possibility that financial ``flash crashes'' are not unlike the catastrophic first-order failure incidents occurring in coupled networks. Specifically, we study the coupled networks that are responsible for financial fluctuations. It appears that ``trend switching phenomena'' that we uncover are remarkably independent of the scale over which they are analyzed. For example, we find that the same laws governing the formation and bursting of the largest financial bubbles also govern the tiniest finance bubbles, over a factor of 1,000,000,000 in time scale [T. Preis, J. Schneider, and H. E. Stanley, ``Switching Processes in Financial Markets,'' Proc. Natl. Acad. Sci. USA 108, 7674 (2011); T. Preis and H. E. Stanley, ``Bubble Trouble: Can a Law Describe Bubbles and Crashes in Financial Markets?'' Physics World 24, No. 5, 29 (May 2011

  10. Carbon neutron star atmospheres

    CERN Document Server

    Suleimanov, V F; Pavlov, G G; Werner, K

    2013-01-01

    The accuracy of measuring the basic parameters of neutron stars is limited in particular by uncertainties in chemical composition of their atmospheres. For example, atmospheres of thermally - emitting neutron stars in supernova remnants might have exotic chemical compositions, and for one of them, the neutron star in CasA, a pure carbon atmosphere has recently been suggested by Ho & Heinke (2009). To test such a composition for other similar sources, a publicly available detailed grid of carbon model atmosphere spectra is needed. We have computed such a grid using the standard LTE approximation and assuming that the magnetic field does not exceed 10^8 G. The opacities and pressure ionization effects are calculated using the Opacity Project approach. We describe the properties of our models and investigate the impact of the adopted assumptions and approximations on the emergent spectra.

  11. The invention of atmosphere.

    Science.gov (United States)

    Martin, Craig

    2015-08-01

    The word "atmosphere" was a neologism Willebrord Snellius created for his Latin translation of Simon Stevin's cosmographical writings. Astronomers and mathematical practitioners, such as Snellius and Christoph Scheiner, applying the techniques of Ibn Mu'ādh and Witelo, were the first to use the term in their calculations of the height of vapors that cause twilight. Their understandings of the atmosphere diverged from Aristotelian divisions of the aerial region. From the early years of the seventeenth century, the term was often associated with atomism or corpuscular matter theory. The concept of the atmosphere changed dramatically with the advent of pneumatic experiments in the middle of the seventeenth century. Pierre Gassendi, Walter Charleton, and Robert Boyle transformed the atmosphere of the mathematicians giving it the characteristics of weight, specific gravity, and fluidity, while disputes about its extent and border remained unresolved.

  12. Ellerman Bombs, Type II White-light Flares and Magnetic Reconnection in the Solar Lower Atmosphere

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Ellerman bombs and Type II white-light flares share many common features despite the large energy gap between them. Both are considered to result from local heating in the solar lower atmosphere. This paper presents numerical simulations of magnetic reconnection occurring in such a deep atmosphere, with the aim to account for the common features of the two phenomena. Our numerical results manifest the following two typical characteristics of the assumed reconnection process: (1) magnetic reconnection saturates in ~600-900 s, which is just the lifetime of the two phenomena; (2) ionization in the upper chromosphere consumes quite a large part of the energy released through reconnection, making the heating effect most significant in the lower chromosphere. The application of the reconnection model to the two phenomena is discussed in detail.

  13. Atmospheric muons: experimental aspects

    OpenAIRE

    Cecchini, S.; Spurio, M.

    2012-01-01

    We present a review of atmospheric muon flux and energy spectrum measurements over almost six decades of muon momentum. Sea-level and underground/water/ice experiments are considered. Possible sources of systematic errors in the measurements are examinated. The characteristics of underground/water muons (muons in bundle, lateral distribution, energy spectrum) are discussed. The connection between the atmospheric muon and neutrino measurements are also reported.

  14. Atmospheric muons: experimental aspects

    Directory of Open Access Journals (Sweden)

    S. Cecchini

    2012-11-01

    Full Text Available We present a review of atmospheric muon flux and energy spectrum measurements over almost six decades of muon momentum. Sea level and underground/water/ice experiments are considered. Possible sources of systematic errors in the measurements are examined. The characteristics of underground/water muons (muons in bundle, lateral distribution, energy spectrum are discussed. The connection between the atmospheric muon and neutrino measurements are also reported.

  15. Observations of quasi-periodic phenomena associated with a large blowout solar jet

    CERN Document Server

    Morton, R J; Erdélyi, R

    2012-01-01

    A variety of periodic phenomena have been observed in conjunction with large solar jets. We aim to find further evidence for {(quasi-)}periodic behaviour in solar jets and determine what the periodic behaviour can tell us about the excitation mechanism and formation process of the large solar jet. Using the 304 {\\AA} (He-II), 171 {\\AA} (Fe IX), 193 {\\AA} (Fe XII/XXIV) and 131 {\\AA} (Fe VIII/XXI) filters on-board the Solar Dynamic Observatory (SDO) Atmospheric Imaging Assembly (AIA), we investigate the intensity oscillations associated with a solar jet. Evidence is provided for multiple magnetic reconnection events occurring between a pre-twisted, closed field and open field lines. Components of the jet are seen in multiple SDO/AIA filters covering a wide range of temperatures, suggesting the jet can be classified as a blowout jet. Two bright, elongated features are observed to be co-spatial with the large jet, appearing at the jet's footpoints. Investigation of these features reveal they are defined by multip...

  16. Macroscopic Modeling of Transport Phenomena in Direct Methanol Fuel Cells

    DEFF Research Database (Denmark)

    Olesen, Anders Christian

    An increasing need for energy efficiency and high energy density has sparked a growing interest in direct methanol fuel cells for portable power applications. This type of fuel cell directly generates electricity from a fuel mixture consisting of methanol and water. Although this technology...... for studying their transport. In this PhD dissertation the macroscopic transport phenomena governing direct methanol fuel cell operation are analyzed, discussed and modeled using the two-fluid approach in the computational fluid dynamics framework of CFX 14. The overall objective of this work is to extend...... the present fundamental understanding of direct methanol fuel cell operation by developing a three-dimensional, two-phase, multi-component, non-isotherm mathematical model including detailed non-ideal thermodynamics, non-equilibrium phase change and non-equilibrium sorption-desorption of methanol and water...

  17. Acoustic resonance phenomena in air bleed channels in aviation engines

    Science.gov (United States)

    Aleksentsev, A. A.; Sazhenkov, A. N.; Sukhinin, S. V.

    2016-11-01

    The existence of axial-radial acoustic resonance oscillations of the basic air flow in bleed channels of aviation engines is demonstrated theoretically and experimentally. Numerical and analytical methods are used to determine the frequency of acoustic resonance oscillations for the lowest modes of open and closed bleed channels of the PS-90A engine. Experimental investigations reveal new acoustic resonance phenomena arising in the air flow in bleed channel cavities in the core duct of this engine owing to instability of the basic air flow. The results of numerical, analytical, and experimental studies of the resonance frequencies reached in the flow in bleed channel cavities in the core duct of the PS-90A engine are found to be in reasonable agreement. As a result, various types of resonance oscillations in bleed channels can be accurately described.

  18. Induced Charge Electrokinetic Phenomena in Tapered Conducting Nanochannels

    CERN Document Server

    Zhao, Cunlu

    2010-01-01

    We conducted a fundamental study of electrokinetics in conducting (ideally polarizable) tapered nanochannels. Based on the theory of induced charge electrokinetics, the external driving electric fields polarize the uncharged conducting walls of nanochannels and consequently induce surface charges on these walls which also can play the roles of physiochemical bond charges in conventional electrokinetics. Due to complex coupling involved in the problem, the complete model including the Poisson equation for electric potential, the Nernst-Planck equation for ions transport and the Navier-stokes equation for liquid transport are adopted to numerically investigate the electrokinetic phenomena inside the tapered nanofluidic nanochannel with conducting walls. The results reveal that, the flow inside the tapered conducting nanochannel exhibit so-called full wave flow rectification that the electrolyte solution always flows from the narrow end of a nanochannel to the wide end for either a forward bias (electric field f...

  19. Supernatural/Paranormal Phenomena: A Passionate Closer Look

    Science.gov (United States)

    Hameed, S.; Robinson, G.; Maulton, J.

    2003-05-01

    A collaboration between a psychologist, a philosopher, and an astronomer resulted in an inter-term (January) course, titled "Supernatural/Paranormal Phenomena: A Passionate Closer Look" at Smith College. The main purpose of the course was to provide students with the tools to evaluate the pseudo-sciences that are so enticing in today's complex and stressful world. We examined some of the reasons why people are attracted to New-Age enterprises that claim to: provide personal insight and social guidance from stars and planets; communicate with the dead; predict the future; prove contact with extraterrestrial beings. The course provided us with an opportunity to introduce the methodology of science and compare it with the claims made by the defenders of pseudo-sciences. We also conducted a survey of paranormal beliefs of enrolled students before and after our inter-term class.

  20. Critical phenomena of emergent magnetic monopoles in a chiral magnet.

    Science.gov (United States)

    Kanazawa, N; Nii, Y; Zhang, X-X; Mishchenko, A S; De Filippis, G; Kagawa, F; Iwasa, Y; Nagaosa, N; Tokura, Y

    2016-05-16

    Second-order continuous phase transitions are characterized by symmetry breaking with order parameters. Topological orders of electrons, characterized by the topological index defined in momentum space, provide a distinct perspective for phase transitions, which are categorized as quantum phase transitions not being accompanied by symmetry breaking. However, there are still limited observations of counterparts in real space. Here we show a real-space topological phase transition in a chiral magnet MnGe, hosting a periodic array of hedgehog and antihedgehog topological spin singularities. This transition is driven by the pair annihilation of the hedgehogs and antihedgehogs acting as monopoles and antimonopoles of the emergent electromagnetic field. Observed anomalies in the magnetoresistivity and phonon softening are consistent with the theoretical prediction of critical phenomena associated with enhanced fluctuations of emergent field near the transition. This finding reveals a vital role of topology of the spins in strongly correlated systems.

  1. Catastrophe characteristics of the condensation and pool boiling phenomena

    Science.gov (United States)

    Ma, Xuehu; Xu, Dunqi; Lin, Jifang

    1995-02-01

    Recently, Utaka proposed two types of the transition modes of dropwise condensation, i.e. the continuous and the jumping modes, and presented a criterion for determining the condensation transition mode. Stylianous and Rose proposed two hypotheses, the coalescence-limited transition and the nucleation site saturation transition. Neither Utaka's criterion nor Rose's hypotheses could clearly interpret the physical mechanisms of the transition both from filmwise to dropwise and from dropwise to pseudofilm condensation, and explicitly presented the main factors affecting the transitions. Kalinin hs given a general review of the transition boiling heat transfer. The catastrophe theory will be applied here to eluicidate the complex phenomena of the transitions of the condensation and boiling pattern states.

  2. Traffic phenomena in biology: from molecular motors to organisms

    CERN Document Server

    Chowdhury, D; Nishinari, K; Chowdhury, Debashish; Schadschneider, Andreas; Nishinari, Katsuhiro

    2007-01-01

    Traffic-like collective movements are observed at almost all levels of biological systems. Molecular motor proteins like, for example, kinesin and dynein, which are the vehicles of almost all intra-cellular transport in eukayotic cells, sometimes encounter traffic jam that manifests as a disease of the organism. Similarly, traffic jam of collagenase MMP-1, which moves on the collagen fibrils of the extracellular matrix of vertebrates, has also been observed in recent experiments. Traffic-like movements of social insects like ants and termites on trails are, perhaps, more familiar in our everyday life. Experimental, theoretical and computational investigations in the last few years have led to a deeper understanding of the generic or common physical principles involved in these phenomena. In particular, some of the methods of non-equilibrium statistical mechanics, pioneered almost a hundred years ago by Einstein, Langevin and others, turned out to be powerful theoretical tools for quantitative analysis of mode...

  3. Surface Phenomena at Silver Nanoparticles in the Context of Toxicology

    DEFF Research Database (Denmark)

    Miclaus, Teodora

    2015-01-01

    associated with engineered nanomaterials. Among these materials, silver nanoparticles are some of the most widely employed and thus represent a major point of focus in nanotoxicology and the topic of this PhD thesis. While nanoparticles have, upon synthesis, well-defined characteristics, specific......Nanoparticle research and applications are rapidly expanding areas and large scale production and use of nanomaterials has prompted concern regarding their safety for humans and the environment. Nanotoxicology aims to offer answers to issues that may arise in regards to potential harmful effects...... of nanotoxicology. The main aim of this PhD research is to investigate these phenomena at the surface of silver nanoparticles under conditions that are relevant for in vitro studies in order to understand their implications for nano-silver toxicity. Upon contact with biological fluids, particles get coated...

  4. Critical Phenomena of the Disorder Driven Localization-Delocalization Transition

    Energy Technology Data Exchange (ETDEWEB)

    Marc Ruhlander

    2002-12-31

    Metal-to-insulator transitions are generally linked to two phenomena: electron-electron correlations and disorder. Although real systems are usually responding to a mixture of both, they can be classified as undergoing a Mott-transition, if the former process dominates, or an Anderson-transition, if the latter dominates. High-T{sub c} superconductors, e.g., are a candidate for the first class. Materials in which disorder drives the metal-to-insulator transition include doped semiconductors and amorphous materials. After briefly reviewing the previous research on transport in disordered materials and the disorder-induced metal-to-insulator transition, a summary of the model and the methods used in subsequent chapters is given.

  5. Prioritization of natural phenomena hazards evaluations for CHG facilities

    CERN Document Server

    Graves, C E

    2001-01-01

    Natural phenomena hazards (NPH) are unexpected acts of nature that pose a threat or danger to workers, the public or to the environment by potential damage to structures, systems and components (SSCs). Earthquakes, extreme winds (hurricane and tornado), flood, volcanic eruption, lightning strike, or extreme cold or heat are examples of NPH. This document outlines the method used to prioritize buildings for inspection following an NPH event and contains the priority list for CH2M HILL Hanford Group, Inc. (CHG) buildings. Once an NPH event occurs and the Hanford Emergency Operations Center (EOC) is activated, this document will be used by the EOC to assign building inspections for the trained evaluators, barring any information from the field.

  6. PREFACE: XI Latin American Workshop on Nonlinear Phenomena

    Science.gov (United States)

    Anteneodo, Celia; da Luz, Marcos G. E.

    2010-09-01

    The XI Latin American Workshop on Nonlinear Phenomena (LAWNP) has been held in Búzios-RJ, Brazil, from 5-9 October 2009. This international conference is one in a series that have gathered biennially, over the past 21 years, physicists and other scientists who direct their work towards several aspects of nonlinear phenomena and complex systems. The main purpose of LAWNP meetings is to create a friendly and motivating environment, such that researchers from Latin America and from other parts of the globe can discuss not only their own latest results but also the trends and perspectives in this very interdisciplinary field of investigation. Hence, it constitutes a forum for promoting scientific collaboration and fomenting the emergence of new ideas, helping to advance the field. The XI edition (LAWNP'09) has gathered more than 230 scientists and students (most from Latin America), covering all of the world (27 different countries from North and South America, Asia, Europe, and Oceania). In total there were 18 plenary lectures, 80 parallel talks, and 140 poster contributions. A stimulating round-table discussion also took place devoted to the present and future of the Latin American Institutions in Complex Phenomena (a summary can be found at http://lawnp09.fis.puc-rio.br, in the Round-Table report link). The 2009 workshop was devoted to a wide scope of themes and points of view, pursuing to include the latest trends and developments in the science of nonlinearity. In this way, we have a great pleasure in publishing this Proceedings volume based on the high quality scientific works presented at LAWNP'09, covering already established methods as well as new approaches, discussing both theoretical and practical aspects, and addressing paradigmatic systems and also completely new problems, in nonlinearity and complexity. In fact, the present volume may be a very valuable reference for those interested in an overview on how nonlinear interactions can affect different

  7. Modelling of density limit phenomena in toroidal helical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, Sanae-I. [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Giannone, Louis [EURATOM-IPP Association, Max Planck Institut fuer Plasmaphysik, Garching (Germany)

    2001-11-01

    The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the density limit oscillation that has been observed on the Wendelstein 7-AS (W7-AS) stellarator. (author)

  8. Critical phenomena in the aspherical gravitational collapse of radiation fluids

    CERN Document Server

    Baumgarte, Thomas W

    2015-01-01

    We study critical phenomena in the gravitational collapse of a radiation fluid. We perform numerical simulations in both spherical symmetry and axisymmetry, and observe critical scaling in both supercritical evolutions, which lead to the formation of a black hole, and subcritical evolutions, in which case the fluid disperses to infinity and leaves behind flat space. We identify the critical solution in spherically symmetric collapse, find evidence for its universality, and study the approach to this critical solution in the absence of spherical symmetry. For the cases that we consider, aspherical deviations from the spherically symmetric critical solution decay in damped oscillations in a manner that is consistent with the behavior found by Mart\\'in-Garc\\'ia and Gundlach in perturbative calculations. Our simulations are performed with an unconstrained evolution code, implemented in spherical polar coordinates, and adopting "moving-puncture" coordinates.

  9. Modelling of density limit phenomena in toroidal helical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, K. [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, S.-I. [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Giannone, L. [Max Planck Institut fuer Plasmaphysik, EURATOM-IPP Association, Garching (Germany)

    2000-03-01

    The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the density limit oscillation that has been observed on the W7-AS stellarator. (author)

  10. Absence of evaporation phenomena in f(T) gravity

    CERN Document Server

    Houndjo, M J S; Myrzakulov, R; Rodrigues, M E

    2013-01-01

    We formulated evaporation phenomena in a generic model of generalized teleparallel gravity in Weitzenbock spacetime. We performed the perturbation analysis around the constant torsion scalar solution named as Nariai spacetime which is an exact solution of field equations as the limiting case of the Schwarzschild-de Sitter and in limit which two back hole and cosmological horizons coincides. By carefully analyze of the horizon perturbation equation we show (anti)evaporation can not be happen. From this result it implies that a typical blackhole in any generic form of generalized teleparallel gravity is frozen in it's initial state. This is an universal feature and completely independence from the form of the model and even the form of the initial phase of horizon perturbations.

  11. Effects of induced vibration modes on droplet sliding phenomena

    Science.gov (United States)

    Mejia, Jose Eduardo; Alvarado, Jorge; Yao, Chun-Wei; Dropwise Condensation Collaboration; Engineered Surfaces Collaboration

    2016-11-01

    An analytical and experimental investigation has been undertaken to understand the effects of induced vibration modes on droplet sliding phenomena. A mathematical model has been postulated which is capable of estimating accurately droplet sliding angles when using hydrophobic and hydrophilic surfaces. The model, which takes into account equilibrium contact angle, contact angle hysteresis, and droplet volume, has been validated using experimental data. The model has been modified to be able to estimate droplet sliding angle when different modes of vibrations are imposed on the surfaces. Experimental results to date reveal that when resonance modes of vibrations are imposed, the droplet sliding angles decrease considerably. The results also indicate that the modified model can be used effectively to relate imposed resonance frequencies to the critical sliding angle of droplets. LSAMP sponsored NSF Fellowship.

  12. Filament Discharge Phenomena in Fingerprint Acquisition by Dielectric Barrier Discharge

    Institute of Scientific and Technical Information of China (English)

    WENG Ming; XU Weijun; LIU Qiang

    2007-01-01

    In this paper, the dielectric barrier discharge fingerprint acquisition technique is introduced. The filament discharge phenomena were observed in the process of fingerprint acquisition. The filament discharge reduced the quality of fingerprint images. Obviously, it was necessary to eliminate streamer discharges in order to get good fingerprint images. The streamer discharge was considered to be the cause of the filament discharge in the experiment. The relationship between the critical electric field and the discharge gap was calculated with the Raether's model of streamer discharge. The calculated results and our experiment proved that it would be difficult for the streamer discharge to occur when the discharge gap was narrow. With a narrow discharge gap, the discharge was homogeneous, and the fingerprint images were clear and large in area. The images obtained in the experiment are very suitable for fingerprint identification as they contain more information.

  13. Some optical and dynamical phenomena in the Rindler model

    CERN Document Server

    Birsin, E

    2014-01-01

    In Rindler's model of a uniformly accelerated reference frame we analyze the apparent shape of rods and marked light rays for the case that the observers as well as the rods and the sources of light are at rest with respect to the Rindler observers. Contrary to the expectation suggested by the strong principle of equivalence, there is no apparent "bending down" of a light ray with direction transversal to the direction of acceleration, but a straight rod oriented orthogonal to the direction of acceleration appears bended "upwards". These optical phenomena are in accordance with the dynamical experience of observers guided by a straight track or a track curved in the same way as the marked light ray, respectively: While the former observer feels a centrifugal force directed "downwards", the centrifugal force for the latter vanishes. The properties of gyroscope transport along such tracks are correspondingly.

  14. A curriculum framework based on archetypal phenomena and technologies

    Science.gov (United States)

    Zubrowski, Bernie

    2002-07-01

    The current crop of published curriculum materials for elementary and middle school makes various claims about their relevancy to the student and their alignment with national standards. Although it may appear that they show improvement in their pedagogical practices and use of recent research, it is argued that they still are founded on questionable assumptions about student learning. The general approach of these curriculum programs is examined in relationship to issues such as the context of learning, the relationship between domain general and domain specific knowledge, and the essential role that aesthetics and personal frameworks play in conceptual change. An alternative paradigm of curriculum development is presented based on the theory of situated cognition. This approach starts with context rather than concept, gives greater weight to students' interpretative frameworks, and provides for a more holistic development. A grade 1-8 framework is presented having archetypal phenomena and technologies as the focus of investigations.

  15. Jet phenomena above null points of the coronal magnetic field

    Science.gov (United States)

    Filippov, B.; Koutchmy, S.; Golub, L.

    2009-12-01

    Short-lived plasma jets of various scales, from giant X-ray jets more than 300 Mm in extent to numerous small jets with sizes typical of macrospicules, are the phenomena observed in the solar corona in extreme ultraviolet and X-ray emission. Small jets are particularly prominent in polar coronal holes. They are close neighbors of tiny bright loops and coincide in time with their sudden brightening and increase in size. The geometric shape of the jets and their location suggest that they arise near singular null points of the coronal magnetic field. These points appear in coronal holes due to the emergence of small bipolar or unipolar magnetic structures within large-scale unipolar cells. Polar jets show a distinct vertical plasma motion in a coronal hole that introduces significant momentum and mass into the solar wind flow. Investigating the dynamics of polar jets can elucidate certain details in the problem of fast solar wind acceleration.

  16. Critical Phenomena of the Disorder Driven Localization-Delocalization Transition

    CERN Document Server

    Marc-Ruehlaende

    2001-01-01

    Metal-to-insulator transitions are generally linked to two phenomena: electron-electron correlations and disorder. Although real systems are usually responding to a mixture of both, they can be classified as undergoing a Mott-transition, if the former process dominates, or an Anderson-transition, if the latter dominates. High-T sub c superconductors, e.g., are a candidate for the first class. Materials in which disorder drives the metal-to-insulator transition include doped semiconductors and amorphous materials. After briefly reviewing the previous research on transport in disordered materials and the disorder-induced metal-to-insulator transition, a summary of the model and the methods used in subsequent chapters is given.

  17. Spatio-temporal phenomena in complex systems with time delays

    Science.gov (United States)

    Yanchuk, Serhiy; Giacomelli, Giovanni

    2017-03-01

    Real-world systems can be strongly influenced by time delays occurring in self-coupling interactions, due to unavoidable finite signal propagation velocities. When the delays become significantly long, complicated high-dimensional phenomena appear and a simple extension of the methods employed in low-dimensional dynamical systems is not feasible. We review the general theory developed in this case, describing the main destabilization mechanisms, the use of visualization tools, and commenting on the most important and effective dynamical indicators as well as their properties in different regimes. We show how a suitable approach, based on a comparison with spatio-temporal systems, represents a powerful instrument for disclosing the very basic mechanism of long-delay systems. Various examples from different models and a series of recent experiments are reported.

  18. An overview of photocatalysis phenomena applied to NOx abatement.

    Science.gov (United States)

    Ângelo, Joana; Andrade, Luísa; Madeira, Luís M; Mendes, Adélio

    2013-11-15

    This review provides a short introduction to photocatalysis technology in terms of the present environmental remediation paradigm and, in particular, NOx photoabatement. The fundamentals of photoelectrochemical devices and the photocatalysis phenomena are reviewed, highlighting the main reaction mechanisms. The critical historical developments on heterogeneous photocatalysis are briefly discussed, giving particular emphasis to the pioneer works in this field. The third part of this work focus mainly on NOx removal technology considering topics such as: TiO2 photochemistry; effect of the operating conditions on the photocatalysis process; Langmuir-Hinshelwood modeling; TiO2 photocatalytic immobilization approaches; and their applications. The last section of the paper presents the main conclusions and perspectives on the opportunities related to this technology.

  19. Stopband Phenomena in the Passband of Left-Handed Metamaterials

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiao-Peng; ZHAO Qian; ZHANG Fu-Li; ZHAO Wei; LIU Ya-Hong

    2006-01-01

    Stopband phenomena are reported in the passband of left-handed metamaterials. The samples with linear defect are designed by removing one layer of split ring resonators (SRRs). It is shown that the left-handed transmission peaks have a distinct transform with the relative deviation of the SRRs centre from the wire centre δ, from a single left-handed peak, double left-handed peaks with different magnitude to no transmission peak, i.e. left-handed properties of metamaterials disappear. Numerical simulation shows that the change of δ makes the effective permeability shift at a frequency range, where stopband occurs. It is thought that the stopband in left-handed passband is due to the symmetry breaking between SRRs and wires in the metamaterials.

  20. Survey of Induced Voltage and Current Phenomena in GIS Substation

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Hassan Hosseini

    2014-03-01

    Full Text Available Induced capacitive voltage and current in high voltage GIS substation is one of the most significant phenomena that may have made some problems in this substation operation. At this study the various equipment of 420 KV Karoon4 substations such as powerhouses, input and output lines, bus-bar and bus-duct have simulated by applying EMTP-RV software. Then with the different condition of single-phase and three-phase faults on the lines in critical conditions, capacitive induction voltage and current by parallel capacitor with circuit breaker is surveyed. The results show the value of this induced current and voltage and that this critical conditions the breakers and dis-connector switches must be able to interrupt this value of current.

  1. Analogue gravitational phenomena in Bose-Einstein condensates

    CERN Document Server

    Finazzi, Stefano

    2012-01-01

    Analogue gravity is based on the simple observation that perturbations propagating in several physical systems can be described by a quantum field theory in a curved spacetime. While phenomena like Hawking radiation are hardly detectable in astrophysical black holes, these effects may be experimentally tested in analogue systems. In this Thesis, focusing on Bose-Einstein condensates, we present our recent results about analogue models of gravity from three main perspectives: as laboratory tests of quantum field theory in curved spacetime, for the techniques that they provide to address various issues in general relativity, and as toy models of quantum gravity. The robustness of Hawking-like particle creation is investigated in flows with a single black hole horizon. Furthermore, we find that condensates with two (white and black) horizons develop a dynamical instability known in general relativity as black hole laser effect. Using techniques borrowed from analogue gravity, we also show that warp drives, which...

  2. Nonlinear thermokinetic phenomena due to the Seebeck effect.

    Science.gov (United States)

    Sugioka, Hideyuki

    2014-07-22

    We propose a novel mechanism to produce nonlinear thermokinetic vortex flows around a circular cylinder with ideally high thermal conductivity in an electrolyte. That is, the nonlinear thermokinetic slip velocity, which is proportional to the square of the temperature gradient [∇(T)0(2)], is derived based on the electrolyte Seebeck effect, heat conduction equation, and Helmholtz–Smoluchowski formula. Different from conventional linear thermokinetic theory, our theory predicts that the inversion of the temperature gradient does not change the direction of the thermokinetic flows and thus a Janus particle using this phenomenon can move to the both hotter and colder regions in a temperature gradient field by changing the direction of its dielectric end. Our findings bridge the gap between the electro- and thermo-kinetic phenomena and provide an integrated physical viewpoint for the interface science.

  3. Control of quantum phenomena: Past, present, and future

    CERN Document Server

    Brif, Constantin; Rabitz, Herschel

    2009-01-01

    Quantum control is concerned with active manipulation of physical and chemical processes on the atomic and molecular scale. This work presents a perspective of progress in the field of control over quantum phenomena, tracing the evolution of theoretical concepts and experimental methods from early developments to the most recent advances. The current experimental successes would be impossible without the development of intense femtosecond laser sources and pulse shapers. The two most critical theoretical insights were (1) realizing that ultrafast atomic and molecular dynamics can be controlled via manipulation of quantum interferences and (2) understanding that optimally shaped ultrafast laser pulses are the most effective means for producing the desired quantum interference patterns in the controlled system. Finally, these theoretical and experimental advances were brought together by the crucial concept of adaptive feedback control, which is a laboratory procedure employing measurement-driven, closed-loop o...

  4. Experimental techniques for the investigation of coupled phenomena in geomaterials

    Science.gov (United States)

    Romero, E.

    2010-06-01

    The paper describes different experimental setups and techniques used to investigate coupled stress, fluid (water and air) and temperature effects on geomaterials. Two temperature controlled cells are described: a) a constant volume cell in which thermal pulses can be performed under controlled hydraulic conditions to induce pore pressure build-up during quasi-undrained heating and later dissipation; and b) an axisymmetric triaxial cell with controlled suction and temperature to perform drained heating and cooling paths under partially saturated states. The paper also presents an experimental setup to perform controlled flow-rate gas injection experiments on argillaceous rocks using a high-pressure triaxial cell. This cell is used to study gas migration phenomena and the conditions under which gas breakthrough processes occur. Selected test results are presented, which show the capabilities of the different experimental setups described to capture main behavioural features.

  5. Bifurcation phenomena in internal dynamics of gear systems

    Directory of Open Access Journals (Sweden)

    Hortel M.

    2007-10-01

    Full Text Available The impact effects in gear mesh represent specific phenomena in the dynamic investigation of highspeed light transmission systems with kinematic couplings. They are caused of greater dynamic than static elastic deformations in meshing gear profiles. In term of internal dynamics they are influenced among others by time heteronomous stiffness functions in gear mesh and resonance tuning of stiffness level. The damping in gear mesh and in gear system is concerned significantly in the amplitude progress, greatness and phase shift of relative motion towards stiffness function alternatively towards its modify form in gear mesh. In consequence of these and another actions rise above resonance characteristics certain singular locations with jump amplitude course.

  6. Quasi-quantum phenomena: the key to understanding homeopathy.

    Science.gov (United States)

    Molski, Marcin

    2010-04-01

    On the basis of the first- and second-order Gompertzian kinetics it has been proved that the crystallization and its reciprocal process of dissolution belong to the class of quasi-quantum non-local coherent phenomena. Hence, there exists a direct link to homeopathy: molecules of the remedy prepared in the process of dilution of the active substance are non-locally interconnected at-a-distance. The results obtained provide strong arguments justifying formulated ad hoc macroscopic versions of quantum non-locality, entanglement and coherence employed in interpretation of the homeopathic remedies activity and effectiveness. In particular they are consistent with the predictions of the weak quantum theory developed by Atmanspacher and coworkers.

  7. Experimental techniques for the investigation of coupled phenomena in geomaterials

    Directory of Open Access Journals (Sweden)

    Romero E.

    2010-06-01

    Full Text Available The paper describes different experimental setups and techniques used to investigate coupled stress, fluid (water and air and temperature effects on geomaterials. Two temperature controlled cells are described: a a constant volume cell in which thermal pulses can be performed under controlled hydraulic conditions to induce pore pressure build-up during quasi-undrained heating and later dissipation; and b an axisymmetric triaxial cell with controlled suction and temperature to perform drained heating and cooling paths under partially saturated states. The paper also presents an experimental setup to perform controlled flow-rate gas injection experiments on argillaceous rocks using a high-pressure triaxial cell. This cell is used to study gas migration phenomena and the conditions under which gas breakthrough processes occur. Selected test results are presented, which show the capabilities of the different experimental setups described to capture main behavioural features.

  8. Coherence In Quantum Chaos, Stochastic Spacetime, And Collective Phenomena

    CERN Document Server

    Shiokawa, K

    1998-01-01

    Various manifestations of coherence properties in quantum and classical dynamics in open and closed systems are studied. Among many different issues and phenomena related to coherence, particular aspects are expounded by models chosen from quantum chaos, quantum optics, mesoscopic and high energy physics, and semiclassical relativity. I show how coherence in quantum and classical systems manifests itself in different forms and is enhanced, altered, and suppressed in the presence of chaos, randomness, boundary, and environment. Author's contributions start from the first time discussion of decoherence in quantum cat map and quantum kicked rotor. Wave propagation in stochastic spacetime is considered as that in random media by extending the analogy of spacetime metric with the refractive index of media...

  9. Searching for fractal phenomena in multidimensional phase-spaces

    Science.gov (United States)

    Blažek, Mikuláš

    2000-07-01

    A unified point of view on the fractal analysis in d-dimensional phase-spaces is presented. It is applicable to the data coming from the counting experiments. Explicit expressions are formulated for the fundamental types of factorial moments characterizing the presence of the fractal phenomena, their number being given by (2 d+1 - 1), as well as for a variety of associated statistical moments; special attention is paid to two and three dimensions. In particular, it is found that scaling properties of the modified dispersion moments are directly related with the presence of empty bins in the corresponding distributions. As to the high-energy experiments, those expressions can be applied to the data presently available, e.g. from LEP, as well as to the data arising in the near future from heavy-ion collisions performed at the CERN collider and from the pp collisions observed at the Tevatron, Fermilab.

  10. Fire phenomena and nonlinearity (II). Catastrophic fire dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Z. [University of Science and Technology, Hefei (China). State Key Laboratory of Fire Science

    2000-09-01

    As one of the most important non-linear mechanisms to cause fire or exacerbate fire disaster, there is a great deal of catastrophe behaviours existing in fire processes. The main tasks of the study of catastrophic fire dynamics are: 1) analysis of the catastrophe mechanisms of discontinuity behaviours in fire systems; 2) investigation of the controlling methods of discontinuity behaviours of fire system; 3) qualitative analysis of the dynamical characteristics of fire systems; and 4) catastrophe classifying of discontinuity phenomena in fire system. The other disciplines, such as physics, chemistry, biology, geoscience, astronomy, or even social sciences (for instance, political, economics, strategics and management science), may also take the similar method to establish the corresponding branch discipline of catastrophe science and catastrophe classification method. It is pointed out that an ignition behaviour of the uniform temperature thermal explosion system under the control of radiation has cusp catastrophe mechanism. 10 refs., 3 figs.

  11. Small-world phenomena in physics: the Ising model

    Energy Technology Data Exchange (ETDEWEB)

    Gitterman, M. [Department of Physics, Bar-Ilan University, Ramat-Gan (Israel)

    2000-12-01

    The Ising system with a small fraction of random long-range interactions is the simplest example of small-world phenomena in physics. Considering the latter both in an annealed and in a quenched state we conclude that: (a) the existence of random long-range interactions leads to a phase transition in the one-dimensional case and (b) there is a minimal average number p of these interactions per site (p<1 in the annealed state, and p{approx_equal}1 in the quenched state) needed for the appearance of the phase transition. Note that the average number of these bonds, pN/2, is much smaller than the total number of bonds, N{sup 2}/2. (author)

  12. Research into surface wave phenomena in sedimentary basins

    Science.gov (United States)

    Wojcik, G. L.; Isenberg, J.; Ma, F.; Richardson, E.

    1981-12-01

    This study is a continuation of an engineering seismology research effort prompted by the sensitivity of guidance sets in Minuteman Wing V to distant earthquakes. An earlier report considers the probable cause of anomalous patterns of seismic alarms triggered by two North American earthquakes. This report extends the previous study by examining the propagation of surface waves from the 1975 Pocatello Valley, Idaho earthquake sequence across Wyoming to Wing V. In addition, the more general question of surface wave phenomena in sedimentary basins is addressed, particularly the effect of laterally inhomogeneous (dipping) basin-bedrock interfaces. Findings indicate that fundamental and first overtone surface waves are significantly modified by the travel path. In contrast, higher modes are relatively unchanged by the travel path, and affect Wing V in much the same way as body waves considered in the previous study.

  13. Magnetic phenomena in holographic superconductivity with Lifshitz scaling

    Directory of Open Access Journals (Sweden)

    Aldo Dector

    2015-09-01

    Full Text Available We investigate the effects of Lifshitz dynamical critical exponent z on a family of minimal D=4+1 holographic superconducting models, with a particular focus on magnetic phenomena. We see that it is possible to have a consistent Ginzburg–Landau approach to holographic superconductivity in a Lifshitz background. By following this phenomenological approach we are able to compute a wide array of physical quantities. We also calculate the Ginzburg–Landau parameter for different condensates, and conclude that in systems with higher dynamical critical exponent, vortex formation is more strongly unfavored energetically and exhibits a stronger Type I behavior. Finally, following the perturbative approach proposed by Maeda, Natsuume and Okamura, we calculate the critical magnetic field of our models for different values of z.

  14. Small-scale topology of solar atmosphere dynamics I: wave sources and wave diffraction

    NARCIS (Netherlands)

    Hoekzema, N.M.; Rutten, R.J.; Brandt, P.N.; Shine, R.A.

    2001-01-01

    We study the small-scale topology of dynamical phenomena in the quiet-sun internet w ork atmosphere,using short-duration Fourier analysis of high-resolution filtergram sequences to obtain statistical estimates for the co-location probability of different fine-structure elements and wave modes. In th

  15. Small-scale topology of solar atmosphere dynamics : II : granulation, K2v grains and waves

    NARCIS (Netherlands)

    Hoekzema, N.M.; Rutten, R.J.

    2001-01-01

    We continue studying the small-scale topology of dynamical phenomena in the quiet-sun internetwork atmosphere throug statistical estimation of the co-location probability of different fine-structure elements and wave modes.In this paper we chart spatial alignments between the granular brig tness st

  16. Ionospheric response to the phenomena occurring below and above it: a summary

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, D.K.; Sharma, P.K. [Department of Applied Sciences and Humanities, Manav Rachna College of Engineering, Faridabad (India)]. E-mail: dkphdes@rediffmail.com; Chand, R.; Rai, J. [Department of Physics, Indian Institute of Technology, Roorkee (India)

    2009-01-15

    Some of well known F{sub 2} layer anomalies might have their origin in lower atmosphere and some have extra terrestrial sources. It has been suggested that the phenomena occurring below the ionosphere such as thunderstorms, lightning/sprites, volcanic eruptions and earthquakes and above the phenomena like corona mass ejection, solar flares and extra terrestrial events may produce F{sub 2} layer signatures. In the present paper we have tried to summarize the effect of some phenomena occurring below the ionosphere like thunderstorms, lightning/sprites and seismic activity and the phenomena such as solar flares which occur above the ionosphere, on the ionospheric electron and ion temperatures. The paper also discusses possibilities. The ionospheric electron and ion temperatures were measured by the RrPAa payload aboard the Iindian SRrOSS-C2 satellite. The normal day's ion and electron temperatures have been compared to the temperatures recorded during the disturbed day. The satellite data corresponding to the disturbance period were analyzed in such way that the other possible effects were eliminated. The data used are from the period 1995-1998 in the altitude range 430-630 km over the Iindian region. The data of thunderstorms activity have been obtained from IMimD, Pune and details of seismic events during this period downloaded from the USGS website and existing literature. The data of solar flares have been obtained from NGDC, Boulder, Colorado, USA. [Spanish] Algunas de las anomalias bien conocidas de la capa F{sub 2} pueden tener su origen en la atmosfera baja y otras pueden tener fuentes extra terrestres. Se ha sugerido que los fenomenos que ocurren bajo la ionosfera, tales como truenos, relampagos/duendes, erupciones volcanicas y temblores, y los que ocurren arriba, como eyecciones masivas de la corona solar, erupciones solares y otros eventos extra terrestres, pueden producir efectos especificos en la capa F{sub 2}. En este trabajo hemos tratado de

  17. NASA's Upper Atmosphere Research Program (UARP) and Atmospheric Chemistry Modeling and Analysis Program (ACMAP): Research Summaries 1997-1999

    Science.gov (United States)

    Kurylo, M. J.; DeCola, P. L.; Kaye, J. A.

    2000-01-01

    Under the mandate contained in the FY 1976 NASA Authorization Act, the National Aeronautics and Space Administration (NASA) has developed and is implementing a comprehensive program of research, technology development, and monitoring of the Earth's upper atmosphere, with emphasis on the upper troposphere and stratosphere. This program aims at expanding our chemical and physical understanding to permit both the quantitative analysis of current perturbations as well as the assessment of possible future changes in this important region of our environment. It is carried out jointly by the Upper Atmosphere Research Program (UARP) and the Atmospheric Chemistry Modeling and Analysis Program (ACMAP), both managed within the Research Division in the Office of Earth Science at NASA. Significant contributions to this effort have also been provided by the Atmospheric Effects of Aviation Project (AEAP) of NASA's Office of Aero-Space Technology. The long-term objectives of the present program are to perform research to: understand the physics, chemistry, and transport processes of the upper troposphere and the stratosphere and their control on the distribution of atmospheric chemical species such as ozone; assess possible perturbations to the composition of the atmosphere caused by human activities and natural phenomena (with a specific emphasis on trace gas geographical distributions, sources, and sinks and the role of trace gases in defining the chemical composition of the upper atmosphere); understand the processes affecting the distributions of radiatively active species in the atmosphere, and the importance of chemical-radiative-dynamical feedbacks on the meteorology and climatology of the stratosphere and troposphere; and understand ozone production, loss, and recovery in an atmosphere with increasing abundances of greenhouse gases. The current report is composed of two parts. Part 1 summarizes the objectives, status, and accomplishments of the research tasks supported

  18. Macroscopic quantum phenomena from the large N perspective

    Science.gov (United States)

    Chou, C. H.; Hu, B. L.; Subaşi, Y.

    2011-07-01

    Macroscopic quantum phenomena (MQP) is a relatively new research venue, with exciting ongoing experiments and bright prospects, yet with surprisingly little theoretical activity. What makes MQP intellectually stimulating is because it is counterpoised against the traditional view that macroscopic means classical. This simplistic and hitherto rarely challenged view need be scrutinized anew, perhaps with much of the conventional wisdoms repealed. In this series of papers we report on a systematic investigation into some key foundational issues of MQP, with the hope of constructing a viable theoretical framework for this new endeavour. The three major themes discussed in these three essays are the large N expansion, the correlation hierarchy and quantum entanglement for systems of 'large' sizes, with many components or degrees of freedom. In this paper we use different theories in a variety of contexts to examine the conditions or criteria whereby a macroscopic quantum system may take on classical attributes, and, more interestingly, that it keeps some of its quantum features. The theories we consider here are, the O(N) quantum mechanical model, semiclassical stochastic gravity and gauge / string theories; the contexts include that of a 'quantum roll' in inflationary cosmology, entropy generation in quantum Vlasov equation for plasmas, the leading order and next-to-leading order large N behaviour, and hydrodynamic / thermodynamic limits. The criteria for classicality in our consideration include the use of uncertainty relations, the correlation between classical canonical variables, randomization of quantum phase, environment-induced decoherence, decoherent history of hydrodynamic variables, etc. All this exercise is to ask only one simple question: Is it really so surprising that quantum features can appear in macroscopic objects? By examining different representative systems where detailed theoretical analysis has been carried out, we find that there is no a priori

  19. Macroscopic quantum phenomena from the large N perspective

    Energy Technology Data Exchange (ETDEWEB)

    Chou, C H [department of Physics, National Cheng Kung University, Tainan, Taiwan 701 (China) and National Center for Theoretical Sciences (South), Tainan, Taiwan 701 (China); Hu, B L; Subasi, Y, E-mail: hubeilok@gmail.com [Joint Quantum Institute and Maryland Center for Fundamental Physics, University of Maryland, College Park, Maryland 20742 (United States)

    2011-07-08

    Macroscopic quantum phenomena (MQP) is a relatively new research venue, with exciting ongoing experiments and bright prospects, yet with surprisingly little theoretical activity. What makes MQP intellectually stimulating is because it is counterpoised against the traditional view that macroscopic means classical. This simplistic and hitherto rarely challenged view need be scrutinized anew, perhaps with much of the conventional wisdoms repealed. In this series of papers we report on a systematic investigation into some key foundational issues of MQP, with the hope of constructing a viable theoretical framework for this new endeavour. The three major themes discussed in these three essays are the large N expansion, the correlation hierarchy and quantum entanglement for systems of 'large' sizes, with many components or degrees of freedom. In this paper we use different theories in a variety of contexts to examine the conditions or criteria whereby a macroscopic quantum system may take on classical attributes, and, more interestingly, that it keeps some of its quantum features. The theories we consider here are, the O(N) quantum mechanical model, semiclassical stochastic gravity and gauge / string theories; the contexts include that of a 'quantum roll' in inflationary cosmology, entropy generation in quantum Vlasov equation for plasmas, the leading order and next-to-leading order large N behaviour, and hydrodynamic / thermodynamic limits. The criteria for classicality in our consideration include the use of uncertainty relations, the correlation between classical canonical variables, randomization of quantum phase, environment-induced decoherence, decoherent history of hydrodynamic variables, etc. All this exercise is to ask only one simple question: Is it really so surprising that quantum features can appear in macroscopic objects? By examining different representative systems where detailed theoretical analysis has been carried out, we find that

  20. Study of nonlinear phenomena in switching DC/DC converters

    Science.gov (United States)

    Iu, Herbert Ho-Ching

    This thesis studies some nonlinear phenomena such as bifurcation and chaos in DC/DC switching converters. Five phases of investigations are described. The first phase reviews the existing tools for analyzing nonlinear systems that are helpful to the investigation of nonlinear phenomena in power electronic circuits. Some of these existing tools are employed to study the nonlinear behaviour of power electronic circuits in the subsequent phases. The second phase focuses on the analysis of bifurcation behaviour of parallel-connected DC/DC converters under a master-slave current sharing scheme. An iterative discrete-time map and its Jacobian are established to predict the onset of period-doubling or Neimark-Sacker bifurcation. Both parallel-connected buck converters and boost converters are studied. The third phase studies an autonomous free-running Cuk converter under a hysteretic current-mode control. Hopf bifurcation is observed, for the first time, in this kind of autonomous power electronic circuits. The method of state-space averaging is employed to predict the occurrence of such bifurcation. Extensive simulations and experiments confirm the predicted results. A typical bifurcation sequence from stable fixed points to chaos, via limit cycles and quasiperiodic orbits, is demonstrated. The fourth phase investigates the possibility of synchronization of two chaotic autonomous free-running Cuk converters. With a particular capacitor voltage as driving signal, synchronization is found possible. Averaged state equations and conditional Lyapunov exponents are used to predict the possibility of synchronization while computer simulations and PSPICE simulations provide the verification. The last phase gives suggestions for future research.

  1. Experimental Studies of Light Emission Phenomena in Superconducting RF Cavitites

    Energy Technology Data Exchange (ETDEWEB)

    Anthony, P.L.; /SLAC; Delayen, J.R.; /Jefferson Lab; Fryberger, D.; /SLAC; Goree, W.S.; Mammosser, J.; /Jefferson Lab /SNS Project, Oak Ridge; Szalata, Z.M.; II, J.G.Weisend /SLAC

    2009-08-04

    Experimental studies of light emission phenomena in superconducting RF cavities, which we categorize under the general heading of cavity lights, are described. The cavity lights data, which were obtained using a small CCD video camera, were collected in a series of nine experimental runs ranging from {approx} 1/2 to {approx} 2 h in duration. The video data were recorded on a standard VHS tape. As the runs progressed, additional instrumentation was added. For the last three runs a LabVIEW controlled data acquisition system was included. These runs furnish evidence for several, possibly related, light emission phenomena. The most intriguing of these is what appear to be small luminous objects {le} 1.5 mm in size, freely moving about in the vacuum space, generally without wall contact, as verified by reflections of the tracks in the cavity walls. In addition, on a number of occasions, these objects were observed to bounce off of the cavity walls. The wall-bounce aspect of most of these events was clearly confirmed by pre-bounce and post-bounce reflections concurrent with the tracks. In one of the later runs, a mode of behavior was observed that was qualitatively different from anything observed in the earlier runs. Perhaps the most perplexing aspect of this new mode was the observation of as many as seven luminous objects arrayed in what might be described as a macromolecular formation, coherently moving about in the interior of the cavity for extended periods of time, evidently without any wall contact. It is suggested that these mobile luminous objects are without explanation within the realm of established physics. Some remarks about more exotic theoretical possibilities are made, and future plans are discussed.

  2. Quantitative phase-field modeling for wetting phenomena.

    Science.gov (United States)

    Badillo, Arnoldo

    2015-03-01

    A new phase-field model is developed for studying partial wetting. The introduction of a third phase representing a solid wall allows for the derivation of a new surface tension force that accounts for energy changes at the contact line. In contrast to other multi-phase-field formulations, the present model does not need the introduction of surface energies for the fluid-wall interactions. Instead, all wetting properties are included in a unique parameter known as the equilibrium contact angle θeq. The model requires the solution of a single elliptic phase-field equation, which, coupled to conservation laws for mass and linear momentum, admits the existence of steady and unsteady compact solutions (compactons). The representation of the wall by an additional phase field allows for the study of wetting phenomena on flat, rough, or patterned surfaces in a straightforward manner. The model contains only two free parameters, a measure of interface thickness W and β, which is used in the definition of the mixture viscosity μ=μlϕl+μvϕv+βμlϕw. The former controls the convergence towards the sharp interface limit and the latter the energy dissipation at the contact line. Simulations on rough surfaces show that by taking values for β higher than 1, the model can reproduce, on average, the effects of pinning events of the contact line during its dynamic motion. The model is able to capture, in good agreement with experimental observations, many physical phenomena fundamental to wetting science, such as the wetting transition on micro-structured surfaces and droplet dynamics on solid substrates.

  3. Numerical simulations of magnetic reconnection in the lower solar atmosphere

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yan Xu; Cheng Fang; Ming-De Ding; Dan-Hui Gao

    2011-01-01

    Observations indicate that Ellerman bombs (EBs) and chromospheric microflares both occur in the lower solar atmosphere, and share many common features,such as temperature enhancements, accompanying jet-like mass motions, short lifetime, and so on. These strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar atmosphere.With gravity, ionization and radiation considered, we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar atmosphere. The influence of different parameters, such as intensity of the magnetic field and anomalous resistivity, on the results are investigated. Our result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic reconnection.The spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with observations. It is found that the typical features of the two phenomena can be qualitatively reproduced.

  4. Early attempts at atmospheric simulations for the Cherenkov Telescope Array

    CERN Document Server

    Rulten, Cameron B

    2014-01-01

    The Cherenkov Telescope Array (CTA) will be the world's first observatory for detecting gamma-rays from astrophysical phenomena and is now in its prototyping phase with construction expected to begin in 2015/16. In this work we present the results from early attempts at detailed simulation studies performed to assess the need for atmospheric monitoring. This will include discussion of some lidar analysis methods with a view to determining a range resolved atmospheric transmission profile. We find that under increased aerosol density levels, simulated gamma-ray astronomy data is systematically shifted leading to softer spectra. With lidar data we show that it is possible to fit atmospheric transmission models needed for generating lookup tables, which are used to infer the energy of a gamma-ray event, thus making it possible to correct affected data that would otherwise be considered unusable.

  5. Wind measurements in Mars' middle atmosphere at equinox and solstice: IRAM Plateau de Bure interferometric CO observations

    CERN Document Server

    Moreno, R; Encrenaz, T; Forget, F; Chassefière, E; Hourdin, F; Guilloteau, S; Guilloteau, St\\'{e}phane

    2007-01-01

    Characterizing the Martian atmosphere is an essential objective to understand its meteorology and its climate. The lower atmosphere (< 40 km) and middle atmosphere (40-80 km) of Mars appear dynamically coupled at much higher levels than in the case of the Earth. The vertical extension of the weather phenomena is considerable with for example Hadley's cells reaching the top of the neutral atmosphere (120 km). The circulation in the middle atmosphere modifies the meteorology of the lower atmosphere, affecting the transport and climatic processes Observations of the CO rotational lines at millimeter (mm) wavelengths (Clancy et al 1990) have strongly contributed in the study of the vertical distribution of this compound and the thermal profile in the atmosphere of Mars over 0-70 km. Singledish observations of the CO Doppler lineshift have allowed direct wind measurements in the martian middle atmosphere near 50 km altitude (Lellouch et al 1991), but at a low spatial resolution (12'') enabling only an essential...

  6. QUIET-SUN NETWORK BRIGHT POINT PHENOMENA WITH SIGMOIDAL SIGNATURES

    Energy Technology Data Exchange (ETDEWEB)

    Chesny, D. L.; Oluseyi, H. M. [Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States); Orange, N. B. [OrangeWave Innovative Science, LLC, Moncks Corner, SC 29461 (United States); Champey, P. R. [Department of Optical Science and Engineering, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2015-12-01

    Ubiquitous solar atmospheric coronal and transition region bright points (BPs) are compact features overlying strong concentrations of magnetic flux. Here, we utilize high-cadence observations from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory to provide the first observations of extreme ultraviolet quiet-Sun (QS) network BP activity associated with sigmoidal structuring. To our knowledge, this previously unresolved fine structure has never been associated with such small-scale QS events. This QS event precedes a bi-directional jet in a compact, low-energy, and low-temperature environment, where evidence is found in support of the typical fan-spine magnetic field topology. As in active regions and micro-sigmoids, the sigmoidal arcade is likely formed via tether-cutting reconnection and precedes peak intensity enhancements and eruptive activity. Our QS BP sigmoid provides a new class of small-scale structuring exhibiting self-organized criticality that highlights a multi-scaled self-similarity between large-scale, high-temperature coronal fields and the small-scale, lower-temperature QS network. Finally, our QS BP sigmoid elevates arguments for coronal heating contributions from cooler atmospheric layers, as this class of structure may provide evidence favoring mass, energy, and helicity injections into the heliosphere.

  7. Quiet-Sun Network Bright Point Phenomena with Sigmoidal Signatures

    Science.gov (United States)

    Chesny, D. L.; Oluseyi, H. M.; Orange, N. B.; Champey, P. R.

    2015-12-01

    Ubiquitous solar atmospheric coronal and transition region bright points (BPs) are compact features overlying strong concentrations of magnetic flux. Here, we utilize high-cadence observations from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory to provide the first observations of extreme ultraviolet quiet-Sun (QS) network BP activity associated with sigmoidal structuring. To our knowledge, this previously unresolved fine structure has never been associated with such small-scale QS events. This QS event precedes a bi-directional jet in a compact, low-energy, and low-temperature environment, where evidence is found in support of the typical fan-spine magnetic field topology. As in active regions and micro-sigmoids, the sigmoidal arcade is likely formed via tether-cutting reconnection and precedes peak intensity enhancements and eruptive activity. Our QS BP sigmoid provides a new class of small-scale structuring exhibiting self-organized criticality that highlights a multi-scaled self-similarity between large-scale, high-temperature coronal fields and the small-scale, lower-temperature QS network. Finally, our QS BP sigmoid elevates arguments for coronal heating contributions from cooler atmospheric layers, as this class of structure may provide evidence favoring mass, energy, and helicity injections into the heliosphere.

  8. Atmospheric Laser Communication.

    Science.gov (United States)

    Fischer(, Kenneth W.; Witiw, Michael R.; Baars+, Jeffrey A.; Oke, T. R.

    2004-05-01

    Atmospheric laser communication, often referred to as free-space optics (FSO) or free-space laser (FSL) communication, is similar to fiber optic cable in terms of carrier wavelength and bandwidth capability, but data are transmitted directly through the atmosphere via laser beams over paths from a few meters to 4 km or longer. FSL uses lasers in the near-infrared spectrum, typically at wavelengths of 850 or 1550 nm. Given these wavelengths, atmospheric attenuation must be considered, and an adequate margin of optical power (dB) must exist to support high system availability (the percentage of time that an FSL link is in operation, typically 99.9%). A visual range of 100 m can attenuate a laser beam at a rate of nearly 130 dB km-1. For short links (rain, and snow frequently become issues. To address these issues, long-term climate data are analyzed to determine the frequency of occurrence of low visibilities and low-cloud ceilings. To estimate availability at a site of interest, adjustments to airport climate data are made to accommodate differences in altitude, geography, and the effects of the urban heat island. In sum, communication via FSL is a feasible alternative to fiber optic cable when atmospheric conditions are considered and properly analyzed.(Current affiliation: The Boeing Company, Seattle, Washington+Current affiliation: Department of Atmospheric Sciences, University of Washington, Seattle, Washington

  9. FOREWORD: Electromagnetic Phenomena and Health - A Continuing Controversy?

    Science.gov (United States)

    Jamieson, Isaac A.; Holdstock, Paul

    2010-05-01

    A variety of natural electromagnetic phenomena - from electrostatic and magnetostatic fields to radiowaves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma radiation - may influence human health and wellbeing (by their presence, intensity or absence) in a number of diverse ways. Some artificially created electromagnetic phenomena may also directly and/or indirectly influence biological functioning, though the levels and extent to which they may do so is still to a large extent open to debate and further investigation. Since the deployment, use and types of technology and materials that can alter the electromagnetic nature of environments to which individuals are exposed are growing at an ever increasing rate; it is necessary to consider and rigorously access the possible biological effects (both beneficial and detrimental) that they may cause, or be instrumental in causing, so that appropriate safety and best practice measures can be introduced/adhered to if and where appropriate. As demonstrated by the papers in these conference proceedings, there is presently a very widespread range of opinions from experts on the best ways to proceed over such matters, indicating that further dialogue is necessary in a way that can satisfactorily address these issues whilst enhancing technological innovation in a sustainable manner and suitably addressing possible health related concerns. It appears that by constructively encouraging dialogue between experts and other stakeholders and the development of 'Win-Win' scenarios and mindsets, where solutions and constructive progress are sought (instead of highlighting problems and differences in opinion - as has often occurred in the past in electromagnetic field (EMF) discourse) - much can be achieved to the benefit of all. It also appears much may be achieved if the possible beneficial health effects of particular types of electromagnetic phenomena, exposure regimes and related factors are investigated more

  10. Current status and challenges in optical turbulence simulations in various layers of the Earth's atmosphere

    Science.gov (United States)

    He, Ping; Nunalee, Christopher G.; Basu, Sukanta; Vorontsov, Mikhail A.; Fiorino, Steven T.

    2014-10-01

    In this study, we present a brief review on the existing approaches for optical turbulence estimation in various layers of the Earth's atmosphere. The advantages and disadvantages of these approaches are also discussed. An alternative approach, based on mesoscale modeling with parameterized turbulence, is proposed and tested for the simulation of refractive index structure parameter (C2n ) in the atmospheric boundary layer. The impacts of a few atmospheric flow phenomena (e.g., low-level jets, island wake vortices, gravity waves) on optical turbulence are discussed. Consideration of diverse geographic settings (e.g., flat terrain, coastal region, ocean islands) makes this study distinct.

  11. Recurrence and interoccurrence behavior of self-organized complex phenomena

    Directory of Open Access Journals (Sweden)

    S. G. Abaimov

    2007-08-01

    Full Text Available The sandpile, forest-fire and slider-block models are said to exhibit self-organized criticality. Associated natural phenomena include landslides, wildfires, and earthquakes. In all cases the frequency-size distributions are well approximated by power laws (fractals. Another important aspect of both the models and natural phenomena is the statistics of interval times. These statistics are particularly important for earthquakes. For earthquakes it is important to make a distinction between interoccurrence and recurrence times. Interoccurrence times are the interval times between earthquakes on all faults in a region whereas recurrence times are interval times between earthquakes on a single fault or fault segment. In many, but not all cases, interoccurrence time statistics are exponential (Poissonian and the events occur randomly. However, the distribution of recurrence times are often Weibull to a good approximation. In this paper we study the interval statistics of slip events using a slider-block model. The behavior of this model is sensitive to the stiffness α of the system, α=kC/kL where kC is the spring constant of the connector springs and kL is the spring constant of the loader plate springs. For a soft system (small α there are no system-wide events and interoccurrence time statistics of the larger events are Poissonian. For a stiff system (large α, system-wide events dominate the energy dissipation and the statistics of the recurrence times between these system-wide events satisfy the Weibull distribution to a good approximation. We argue that this applicability of the Weibull distribution is due to the power-law (scale invariant behavior of the hazard function, i.e. the probability that the next event will occur at a time t0 after the last event has a power-law dependence on t0. The Weibull distribution is the only distribution that

  12. Steel oxidation phenomena during Molten Corium siliceous Concrete Interaction (MCCI)

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Brusset, Mathieu; Piluso, Pascal [CEA/DEN/Cadarache, SMTA/LPMA, 13108 St. Paul lez-Durance (France); Balat-Pichelin, Marianne [PROMES-CNRS Laboratory, 7 rue du four solaire, 66120 Font-Romeu Odeillo (France); Bottomley, Paul David; Wiss, Thierry [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe, German (Germany)

    2015-02-15

    Highlights: • Corium metallic phase oxidation during corium-concrete interaction is studied. • Steel is separated from the oxide melt or emulsified inside the oxide melt. • Oxidation layer depends on the nature of the interfaces and location in the corium. • Oxides formed are (Fe,Cr){sub 3}O{sub 4} and Cr{sub 2}O{sub 3}. • Concrete gases are not sufficient to explain the experimental steel oxidation. - Abstract: The VULCANO facility at CEA Cadarache is a Molten Corium Concrete Interaction (MCCI) installation for testing material reactions representative of the late stages of a nuclear reactor severe accident. The objectives of the VBS-U3 test were to study ablation phenomena and oxidation of the metallic phase when two liquid phases are present: oxide phase and metallic phase (steel). In this paper we describe the materials post-test analysis of the VULCANO VBS-U3 test performed at the Institute for Transuranium Elements in Karlsruhe (JRC-ITU) with the focus on the metallic phase oxidation of the corium. Post-test analyses show that the remaining metallic phase of the corium is under two forms: drops discontinuously dispersed in the oxide phase forming an emulsion and a continuous metallic ingot clearly separated from the oxide phase. In average, taking into account or not the metallic phase dispersed in the oxide phase, between 60% and 70% of the steel has been oxidized. The size of the drops and their proportion in the oxide phase is depending on their distance from horizontal and vertical walls of the concrete test section. Oxidation mechanisms are mainly depending on two parameters: nature of the metallic interface and localization in the test section. Calculations at thermodynamic equilibrium show that the only product from steel oxidation is (Fe,Cr){sub 3}O{sub 4}, Cr{sub 2}O{sub 3} is never formed. Moreover taking into account the two gaseous species coming from the concrete (CO{sub 2} and H{sub 2}O), considered up to now as being the only sources

  13. Atmosphere and Ambient Space

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Atmosphere and Ambient Space This paper explores the relation between atmosphere and ambient space. Atmosphere and ambient space share many salient properties. They are both ontologically indeterminate, constantly varying and formally diffuse and they are both experienced as a subtle, non......-signifying property of a given space. But from a certain point of view, the two concepts also designate quite dissimilar experiences of space. To be ’ambient’ means to surround. Accordingly, ambient space is that space, which surrounds something or somebody. (Gibson 1987: 65) Since space is essentially...... of a surrounding character, all space can thus be described as having a fundamentally ambient character. So what precisely is an ambient space, then? As I will argue in my presentation, ambient space is a sensory effect of spatiality when a space is experienced as being particularly surrounding: a ‘space effect...

  14. Phenomenology of atmospheric neutrinos

    Directory of Open Access Journals (Sweden)

    Fedynitch Anatoli

    2016-01-01

    Full Text Available The detection of astrophysical neutrinos, certainly a break-through result, introduced new experimental challenges and fundamental questions about acceleration mechanisms of cosmic rays. On one hand IceCube succeeded in finding an unambiguous proof for the existence of a diffuse astrophysical neutrino flux, on the other hand the precise determination of its spectral index and normalization requires a better knowledge about the atmospheric background at hundreds of TeV and PeV energies. Atmospheric neutrinos in this energy range originate mostly from decays of heavy-flavor mesons, which production in the phase space relevant for prompt leptons is uncertain. Current accelerator-based experiments are limited by detector acceptance and not so much by the collision energy. This paper recaps phenomenological aspects of atmospheric leptons and calculation methods, linking recent progress in flux predictions with particle physics at colliders, in particular the Large Hadron Collider.

  15. Observations of Exoplanet Atmospheres

    CERN Document Server

    Crossfield, Ian J M

    2015-01-01

    Detailed characterization of an extrasolar planet's atmosphere provides the best hope for distinguishing the makeup of its outer layers, and the only hope for understanding the interplay between initial composition, chemistry, dynamics & circulation, and disequilibrium processes. In recent years, some areas have seen rapid progress while developments in others have come more slowly and/or have been hotly contested. This article gives an observer's perspective on the current understanding of extrasolar planet atmospheres prior to the considerable advances expected from the next generation of observing facilities. Atmospheric processes of both transiting and directly-imaged planets are discussed, including molecular and atomic abundances, cloud properties, thermal structure, and planetary energy budgets. In the future we can expect a continuing and accelerating stream of new discoveries, which will fuel the ongoing exoplanet revolution for many years to come.

  16. Atmospheres of Brown Dwarfs

    CERN Document Server

    Helling, Christiane

    2014-01-01

    Brown Dwarfs are the coolest class of stellar objects known to date. Our present perception is that Brown Dwarfs follow the principles of star formation, and that Brown Dwarfs share many characteristics with planets. Being the darkest and lowest mass stars known makes Brown Dwarfs also the coolest stars known. This has profound implication for their spectral fingerprints. Brown Dwarfs cover a range of effective temperatures which cause brown dwarfs atmospheres to be a sequence that gradually changes from a M-dwarf-like spectrum into a planet-like spectrum. This further implies that below an effective temperature of < 2800K, clouds form already in atmospheres of objects marking the boundary between M-Dwarfs and brown dwarfs. Recent developments have sparked the interest in plasma processes in such very cool atmospheres: sporadic and quiescent radio emission has been observed in combination with decaying Xray-activity indicators across the fully convective boundary.

  17. Dreaming of Atmospheres

    Science.gov (United States)

    Waldmann, Ingo

    2016-10-01

    Radiative transfer retrievals have become the standard in modelling of exoplanetary transmission and emission spectra. Analysing currently available observations of exoplanetary atmospheres often invoke large and correlated parameter spaces that can be difficult to map or constrain.To address these issues, we have developed the Tau-REx (tau-retrieval of exoplanets) retrieval and the RobERt spectral recognition algorithms. Tau-REx is a bayesian atmospheric retrieval framework using Nested Sampling and cluster computing to fully map these large correlated parameter spaces. Nonetheless, data volumes can become prohibitively large and we must often select a subset of potential molecular/atomic absorbers in an atmosphere.In the era of open-source, automated and self-sufficient retrieval algorithms, such manual input should be avoided. User dependent input could, in worst case scenarios, lead to incomplete models and biases in the retrieval. The RobERt algorithm is build to address these issues. RobERt is a deep belief neural (DBN) networks trained to accurately recognise molecular signatures for a wide range of planets, atmospheric thermal profiles and compositions. Using these deep neural networks, we work towards retrieval algorithms that themselves understand the nature of the observed spectra, are able to learn from current and past data and make sensible qualitative preselections of atmospheric opacities to be used for the quantitative stage of the retrieval process.In this talk I will discuss how neural networks and Bayesian Nested Sampling can be used to solve highly degenerate spectral retrieval problems and what 'dreaming' neural networks can tell us about atmospheric characteristics.

  18. Exoplanet atmospheres physical processes

    CERN Document Server

    Seager, Sara

    2010-01-01

    Over the past twenty years, astronomers have identified hundreds of extrasolar planets--planets orbiting stars other than the sun. Recent research in this burgeoning field has made it possible to observe and measure the atmospheres of these exoplanets. This is the first textbook to describe the basic physical processes--including radiative transfer, molecular absorption, and chemical processes--common to all planetary atmospheres, as well as the transit, eclipse, and thermal phase variation observations that are unique to exoplanets. In each chapter, Sara Seager offers a conceptual introdu

  19. Symmetries in atmospheric sciences

    CERN Document Server

    Bihlo, Alexander

    2009-01-01

    Selected applications of symmetry methods in the atmospheric sciences are reviewed briefly. In particular, focus is put on the utilisation of the classical Lie symmetry approach to derive classes of exact solutions from atmospheric models. This is illustrated with the barotropic vorticity equation. Moreover, the possibility for construction of partially-invariant solutions is discussed for this model. A further point is a discussion of using symmetries for relating different classes of differential equations. This is illustrated with the spherical and the potential vorticity equation. Finally, discrete symmetries are used to derive the minimal finite-mode version of the vorticity equation first discussed by E. Lorenz (1960) in a sound mathematical fashion.

  20. Macroscopic Quantum Phenomena from the Correlation, Coupling and Criticality Perspectives

    CERN Document Server

    Chou, C H; Subasi, Y

    2011-01-01

    In this sequel paper we explore how macroscopic quantum phenomena can be measured or understood from the behavior of quantum correlations which exist in a quantum system of many particles or components and how the interaction strengths change with energy or scale, under ordinary situations and when the system is near its critical point. We use the nPI (master) effective action related to the Boltzmann-BBGKY / Schwinger-Dyson hierarchy of equations as a tool for systemizing the contributions of higher order correlation functions to the dynamics of lower order correlation functions. Together with the large N expansion discussed in our first paper(MQP1) we explore 1) the conditions whereby an H-theorem is obtained, which can be viewed as a signifier of the emergence of macroscopic behavior in the system. We give two more examples from past work: 2) the nonequilibrium dynamics of N atoms in an optical lattice under the large $\\cal N$ (field components), 2PI and second order perturbative expansions, illustrating h...

  1. Compensatory recombination phenomena of neurological functions in central dysphagia patients

    Directory of Open Access Journals (Sweden)

    Xiao-dong Yuan

    2015-01-01

    Full Text Available We speculate that cortical reactions evoked by swallowing activity may be abnormal in patients with central infarction with dysphagia. The present study aimed to detect functional imaging features of cerebral cortex in central dysphagia patients by using blood oxygen level-dependent functional magnetic resonance imaging techniques. The results showed that when normal controls swallowed, primary motor cortex (BA4, insula (BA13, premotor cortex (BA6/8, supramarginal gyrus (BA40, and anterior cingulate cortex (BA24/32 were activated, and that the size of the activated areas were larger in the left hemisphere compared with the right. In recurrent cerebral infarction patients with central dysphagia, BA4, BA13, BA40 and BA6/8 areas were activated, while the degree of activation in BA24/32 was decreased. Additionally, more areas were activated, including posterior cingulate cortex (BA23/31, visual association cortex (BA18/19, primary auditory cortex (BA41 and parahippocampal cortex (BA36. Somatosensory association cortex (BA7 and left cerebellum in patients with recurrent cerebral infarction with central dysphagia were also activated. Experimental findings suggest that the cerebral cortex has obvious hemisphere lateralization in response to swallowing, and patients with recurrent cerebral infarction with central dysphagia show compensatory recombination phenomena of neurological functions. In rehabilitative treatment, using the favorite food of patients can stimulate swallowing through visual, auditory, and other nerve conduction pathways, thus promoting compensatory recombination of the central cortex functions.

  2. Hydrogen-methane separation processes and related phenomena. [112 references

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, J.T.; Wang, S.S.; Yang, R.T.

    1981-01-01

    A thorough and up-dated literature survey has been conducted on processes for separating hydrogen and methane. This was done in conjunction with our work of developing a more energy-efficient and lower-cost process based on cyclic, fixed-bed processes using coal chars as the sorbents. Although the review has covered all hydrocarbon separation processes, the focuses were on physical adsorption phenomena and theories (for both single and mixed gases), surface and pore characteristics of coals and heat-treated coals, and the continuous or semi-continuous chromatographic separation methods. There has been a sharply increasing interest in the past 10 to 15 years in developing processes for hydrocarbon separation based on adsorption/desorption; this is particularly true since the energy costs became increasingly higher recently. The rigorous work on competitive adsorption and on the cyclic (including parametric pumping) processes has all been done in the past 13 years. On the other hand, it is disappointing to find the absence of knowledge on adsorption on coal chars and the lack of it on adsorption on raw coals as well.

  3. Optimised prefactored compact schemes for linear wave propagation phenomena

    Science.gov (United States)

    Rona, A.; Spisso, I.; Hall, E.; Bernardini, M.; Pirozzoli, S.

    2017-01-01

    A family of space- and time-optimised prefactored compact schemes are developed that minimise the computational cost for given levels of numerical error in wave propagation phenomena, with special reference to aerodynamic sound. This work extends the approach of Pirozzoli [1] to the MacCormack type prefactored compact high-order schemes developed by Hixon [2], in which their shorter Padé stencil from the prefactorisation leads to a simpler enforcement of numerical boundary conditions. An explicit low-storage multi-step Runge-Kutta integration advances the states in time. Theoretical predictions for spatial and temporal error bounds are derived for the cost-optimised schemes and compared against benchmark schemes of current use in computational aeroacoustic applications in terms of computational cost for a given relative numerical error value. One- and two-dimensional test cases are presented to examine the effectiveness of the cost-optimised schemes for practical flow computations. An effectiveness up to about 50% higher than the standard schemes is verified for the linear one-dimensional advection solver, which is a popular baseline solver kernel for computational physics problems. A substantial error reduction for a given cost is also obtained in the more complex case of a two-dimensional acoustic pulse propagation, provided the optimised schemes are made to operate close to their nominal design points.

  4. A spectacular coronal mass ejection event and associated phenomena

    Science.gov (United States)

    Ma, Yuan; Li, Chun-Sheng; Song, Qian

    Based on the data taken from S. G. D. and relevant simultaneous observations of solar radio bursts, gamma-ray emission and geophysical effects on June 15, 1991 the relationships among these phenomena are discussed in this paper. Through the analyses it is considered that proton events and GLE events occurred on June 15 in 1991, which were the geophysic responses caused by CME (V>=750 km/s). Simultaneous observation of the bursts at the centimetric and decimetric wavelengths can obtain the U-shape spectrum of speak fluxes, which is still one of the effective tools for predicting proton events and its production mechanism can be explained by using the acceleration of the direct current field parallel to the magnetic field in the electric current sheet formed in the process of the production of spray prominences. However, the process in which electrons are accelerated up to the high energy state remains to be explained. The whole event of June 15 1991, from the coronal matter ejection (or the spray prominences in active regions) to the production of various geophysic effects, has explained and verified.

  5. The role of the microvascular tortuosity in tumor transport phenomena.

    Science.gov (United States)

    Penta, R; Ambrosi, D

    2015-01-07

    The role of the microvascular network geometry in transport phenomena in solid tumors and its interplay with the leakage and pressure drop across the vessels is qualitatively and quantitatively discussed. Our starting point is a multiscale homogenization, suggested by the sharp length scale separation that exists between the characteristic vessels and the tumor tissue spatial scales, referred to as the microscale and the macroscale, respectively. The coupling between interstitial and capillary compartment is described by a double Darcy model on the macroscale, whereas the geometric information on the microvascular structure is encoded in the effective hydraulic conductivities, which are numerically computed by solving classical differential problems on the microscale representative cell. Then, microscale information is injected into the macroscopic model, which is analytically solved in a prototypical geometry and compared with previous experimentally validated, phenomenological models. In this way, we are able to capture the role of the standard blood flow determinants in the tumor, such as tumor radius, tissue hydraulic conductivity and vessels permeability, as well as influence of the vascular tortuosity on fluid convection. The results quantitatively confirm that transport of blood (and, as a consequence, of any advected anti-cancer drug) can be dramatically impaired by increasing the geometrical complexity of the microvasculature. Hence, our quantitative analysis supports the argument that geometric regularization of the capillary network improves blood transport and drug delivery in the tumor mass.

  6. Quantum Non-Objectivity from Performativity of Quantum Phenomena

    CERN Document Server

    Khrennikov, Andrei

    2014-01-01

    We analyze the logical foundations of quantum mechanics (QM) by stressing non-objectivity of quantum observables and the absence of logical atoms in QM. We argue that the matter of quantum non-objectivity is that, on the one hand, the formalism of QM constructed as a mathematical theory is self-consistent, but, on the other hand, quantum phenomena as results of experimenter's performances are not self-consistent. This self-inconsistency is an effect of that the language of QM differs much from the language of human performances. The first is the language of a mathematical theory which uses some Aristotelian and Russellian assumptions (e.g., the assumption that there are logical atoms). The second language consists of performative propositions which are self-consistent only from the viewpoint of conventional mathematical theory, but they satisfy another logic which is non-Aristotelian. Hence, the representation of quantum reality in linguistic terms may be different: from a mathematical theory to a logic of pe...

  7. The Natural Emergence of (Bio)Semiosic Phenomena.

    Science.gov (United States)

    van Hateren, J H

    Biological organisms appear to have agency, goals, and meaningful behaviour. One possibility is that this is mere appearance, where such properties are not real, but only 'as if' consequences of the physiological structure of organisms. Another possibility is that these properties are real, as emerging from the organism's structure and from how the organism interacts with its environment. Here I will discuss a recent theory showing that the latter position is most likely correct, and argue that the theory is largely consistent with the basics of the field of biosemiotics. The theory can be represented as a triad that resembles the semiotic triad proposed by Peirce, which connects a sign with its object through a process of interpretation. In the theory presented, the sign is an internalized version of fitness (i.e., expected reproductive rate) which refers to the true fitness through a feedback loop that in effect produces interpretation. The feedback loop entangles deterministic and stochastic forms of causation in such a way that genuine agency, goal-directedness, and their associated meaning emerge. It produces a strong form of emergence not reducible to its constituents. The result is that novel phenomena arise that are real and necessary components for a complete understanding of living organisms.

  8. Cooperative behavior of molecular motors: Cargo transport and traffic phenomena

    Science.gov (United States)

    Lipowsky, Reinhard; Beeg, Janina; Dimova, Rumiana; Klumpp, Stefan; Müller, Melanie J. I.

    2010-01-01

    All eukaryotic cells including those of our own body contain complex transport systems based on molecular motors which walk along cytoskeletal filaments. These motors are rather small and make discrete mechanical steps with a step size of the order of 10 nm but are able to pull cargo particles over much larger distances, from micrometers up to meters. In vivo, the intracellular cargos include large membrane-bounded organelles, smaller vesicles, a subset of mRNAs, cytoskeletal filaments, and various protein building blocks, which are transported between different cell compartments. This cargo transport is usually performed by teams of motors. If all motors belong to the same molecular species, the cooperative action of the motors leads to uni-directional transport with a strongly increased run length and with a characteristic force dependence of the velocity distributions. If two antagonistic teams of motors pull on the same cargo particle, they perform a stochastic tug-of-war, which is characterized by a subtle force balance between the two motor teams and leads to several distinct patterns of bi-directional transport. So far, all experimental observations on bi-directional transport are consistent with such a tug-of-war. If many motors and/or cargo particles are transported along the filaments, one encounters various traffic phenomena. Depending on their mutual interactions and the compartment geometry, the motors form various spatio-temporal patterns such as traffic jams, and undergo nonequilibrium phase transitions between different patterns of transport.

  9. Recent results on anisotropic flow and related phenomena in ALICE

    CERN Document Server

    Bilandzic, Ante

    2016-01-01

    The exploration of properties of an extreme state of matter, the Quark--Gluon Plasma, has broken new ground with the recent Run 2 operation of the Large Hadron Collider with heavy-ion collisions at the highest energy to date. With the heavy-ion data taken at the end of 2015, the ALICE Collaboration has made the first observation of anisotropic flow of charged particles and related phenomena in lead--lead collisions at the record breaking energy of 5.02 TeV per nucleon pair. The Run 2 results come after the proton-lead collisions, which provided a lot of unexpected results obtained with two- and multi-particle correlation techniques. In these proceedings, a brief overview of these results will be shown. We will discuss how they further enlighten the properties of matter produced in ultrarelativistic nuclear collisions. We indicate the possibility that, to leading order, the striking universality of flow results obtained with correlation techniques in pp, p--A and A--A collisions might have purely mathematical ...

  10. Epigenetic phenomena and the evolution of plant allopolyploids

    Institute of Scientific and Technical Information of China (English)

    BaoLiu; JonathanF.Wendel

    2005-01-01

    Allopolyploid speciation is widespread in plants, yet the molecular requirements for successful orchestration of coordinated gene expression for two divergent and reunited genomes are poorly understood. Recent studies in several plant systems have revealed that allopolyploid genesis under both synthetic and natural conditions often is accompanied by rapid and sometimes evolutionarily conserved epigeuetic changes, including alteration in cytosine methylation patterns, rapid silencing in ribosomal RNA and proteincoding genes, and de-repression of dormant transposable elements. These changes are inter-related and likely arise from chromatin remodeling and its effects on epigenetic codes during and subsequent to allopolyploid formation. Epigenetic modifications could produce adaptive epimutations and novel phenotypes, some of which may be evolutionarily stable for millions of years, thereby representing a vast reservoir of latent variation that may be episodically released and made visible to selection. This epigenetic variation may contribute to several important attributes of allopolyploidy, including functional diversification or subfunctionalization of duplicated genes, genetic and cytological diploidization, and quenching of incompatible inter-genomic interactions that are characteristic of allopolyploids. It is likely that the evolutionary success of allopolyploidy is in part attributatble to epigenetic phenomena that we are only just beginning to understand.

  11. Thermal dynamics of thermoelectric phenomena from frequency resolved methods

    Science.gov (United States)

    García-Cañadas, J.; Min, G.

    2016-03-01

    Understanding the dynamics of thermoelectric (TE) phenomena is important for the detailed knowledge of the operation of TE materials and devices. By analyzing the impedance response of both a single TE element and a TE device under suspended conditions, we provide new insights into the thermal dynamics of these systems. The analysis is performed employing parameters such as the thermal penetration depth, the characteristic thermal diffusion frequency and the thermal diffusion time. It is shown that in both systems the dynamics of the thermoelectric response is governed by how the Peltier heat production/absorption at the junctions evolves. In a single thermoelement, at high frequencies the thermal waves diffuse semi-infinitely from the junctions towards the half-length. When the frequency is reduced, the thermal waves can penetrate further and eventually reach the half-length where they start to cancel each other and further penetration is blocked. In the case of a TE module, semi-infinite thermal diffusion along the thickness of the ceramic layers occurs at the highest frequencies. As the frequency is decreased, heat storage in the ceramics becomes dominant and starts to compete with the diffusion of the thermal waves towards the half-length of the thermoelements. Finally, the cancellation of the waves occurs at the lowest frequencies. It is demonstrated that the analysis is able to identify and separate the different physical processes and to provide a detailed understanding of the dynamics of different thermoelectric effects.

  12. A variational approach to fracture and other inelastic phenomena

    CERN Document Server

    Piero, Gianpietro

    2014-01-01

    This book exposes a number of mathematical models for fracture of growing difficulty. All models are treated in a unified way, based on incremental energy minimization. They differ from each other by the assumptions made on the inelastic part of the total energy, here called the "cohesive energy". Each model describes a specific aspect of material response, and particular care is devoted to underline the correspondence of each model to the experiments.  The content of the book is  a re-elaboration of the lectures delivered at the First Sperlonga Summer School on Mechanics and Engineering Sciences in September 2011. In the year and a half elapsed after the course, the material has been revised and enriched with new and partially unpublished results. Significant additions have been introduced in the occasion of the course "The variational approach to fracture and other inelastic phenomena", delivered at SISSA, Trieste, in March 2013.  The Notes reflect a research line carried on by the writer over the yea...

  13. Phenomena of Foamed Concrete under Rolling of Aircraft Wheels

    Science.gov (United States)

    Jiang, Chun-shui; Yao, Hong-yu; Xiao, Xian-bo; Kong, Xiang-jun; Shi, Ya-jie

    2014-04-01

    Engineered Material Arresting System (EMAS) is an effective technique to reduce hazards associated with aircraft overrunning runway. In order to ascertain phenomena of the foamed concrete used for EMAS under rolling of aircraft wheel, a specially designed experimental setup was built which employed Boeing 737 aircraft wheels bearing actual vertical loads to roll through the foamed concrete. A number of experiments were conducted upon this setup. It is discovered that the wheel rolls the concrete in a pure rolling manner and crushes the concrete downwards, instead of crushing it forward, as long as the concrete is not higher than the wheel axle. The concrete is compressed into powder in-situ by the wheel and then is brought to bottom of the wheel. The powder under the wheel is loose and thus is not able to sustain wheel braking. It is also found that after being rolled by the wheel the concrete exhibits either of two states, i.e. either 'crushed through' whole thickness of the concrete or 'crushed halfway', depending on combination of strength of the concrete, thickness of the concrete, vertical load the wheel carries, tire dimension and tire pressure. A new EMAS design concept is developed that if an EMAS design results in the 'crushed through' state for the main gears while the 'crushed halfway' state for the nose gear, the arresting bed would be optimal to accommodate the large difference in strength between the nose gear and the main gear of an aircraft.

  14. The 1638 earthquakes, migratory phenomena and geolinguistic consequences in Calabria

    Directory of Open Access Journals (Sweden)

    J. Trumper

    1995-06-01

    Full Text Available Two disastrous earthquakes occurred in Calabria (Southern Italy in 1638: on March 27th the first one had a destructive damage area on the Tyrrheniail side of Mid-Calabria. the second one hit the east side of the same region on June 9th. In historical times they are the most intensive seismic events in their respective epicentral areas. so that the reconstruction of their effects is very important for the analysis and assessment of seismic risk. They strongly influenced, moreover, the development of the economy and socio-cultural status of many urban communities. A study of these shocks has been carried out and has implied a thorough re-evaluation of the historical sources of information already known and the exploitation of possible new sources. The two macroseismic fields have been reconstructed: in particular that of the second seismic event, the strongest one in its epicentral area. stimulates a thorough revision of the seismotectonics of the Middle-eastern Calabria. Moreover the reconstruction of the historical facts accompanying and following the earthquakes has furnished elements that help to explain observed anomalies in the spatial distribution of Calabrian dialect phenomena.

  15. Various Synchronization Phenomena in Discrete-Time Coupled Chaotic Rotors

    Science.gov (United States)

    Morino, K.; Horita, T.; Miyazaki, S.

    2010-06-01

    Various synchronizations and related phenomena in discrete-time coupled chaotic rotors are studied. For unidirectional and bidirectional couplings, various dynamical forms of chaotic phase synchronization (CPS) and their relation to the Lyapunov spectra are shown. For a small positive maximum Lyapunov exponent of the coupled element in the case of the unidirectional coupling, the coupling strength at which CPS is achieved almost coincides with the coupling strength at which generalized synchronization (GS) is achieved. On the other hand, for a large positive maximum Lyapunov exponent, the coupling strength is much smaller on the CPS transition point than on the GS transition point. Statistical properties of the phase difference are analytically and numerically studied by large-deviation analysis. On the basis of the grand canonical formalism, the fluctuation spectrum is theoretically derived, which is compared with the numerical results. These agree with the theoretical es timation, and large deviations are detected out of the domain in which the central limit theorem cannot be applied.

  16. Investigating paranormal phenomena: Functional brain imaging of telepathy

    Directory of Open Access Journals (Sweden)

    Venkatasubramanian Ganesan

    2008-01-01

    Full Text Available Aim: "Telepathy" is defined as "the communication of impressions of any kind from one mind to another, independently of the recognized channels of sense". Meta-analyses of "ganzfield" studies as well as "card-guessing task" studies provide compelling evidence for the existence of telepathic phenomena. The aim of this study was to elucidate the neural basis of telepathy by examining an individual with this special ability. Materials and Methods: Using functional MRI, we examined a famous "mentalist" while he was performing a telepathic task in a 1.5 T scanner. A matched control subject without this special ability was also examined under similar conditions. Results: The mentalist demonstrated significant activation of the right parahippocampal gyrus after successful performance of a telepathic task. The comparison subject, who did not show any telepathic ability, demonstrated significant activation of the left inferior frontal gyrus. Conclusions: The findings of this study are suggestive of a limbic basis for telepathy and warrant further systematic research.

  17. Thermal dynamics of thermoelectric phenomena from frequency resolved methods

    Directory of Open Access Journals (Sweden)

    J. García-Cañadas

    2016-03-01

    Full Text Available Understanding the dynamics of thermoelectric (TE phenomena is important for the detailed knowledge of the operation of TE materials and devices. By analyzing the impedance response of both a single TE element and a TE device under suspended conditions, we provide new insights into the thermal dynamics of these systems. The analysis is performed employing parameters such as the thermal penetration depth, the characteristic thermal diffusion frequency and the thermal diffusion time. It is shown that in both systems the dynamics of the thermoelectric response is governed by how the Peltier heat production/absorption at the junctions evolves. In a single thermoelement, at high frequencies the thermal waves diffuse semi-infinitely from the junctions towards the half-length. When the frequency is reduced, the thermal waves can penetrate further and eventually reach the half-length where they start to cancel each other and further penetration is blocked. In the case of a TE module, semi-infinite thermal diffusion along the thickness of the ceramic layers occurs at the highest frequencies. As the frequency is decreased, heat storage in the ceramics becomes dominant and starts to compete with the diffusion of the thermal waves towards the half-length of the thermoelements. Finally, the cancellation of the waves occurs at the lowest frequencies. It is demonstrated that the analysis is able to identify and separate the different physical processes and to provide a detailed understanding of the dynamics of different thermoelectric effects.

  18. Molecular dynamics simulation for aggregation phenomena of nanocolloids

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Nonequilibrium molecular dynamics (MD) method was used to study the dielectrophoresis (DEP) motion of nanocolloids in non-uniform electric field. By changing the electric field strength and system temperature, aggregation phenomena of nanocolloids was analyzed. Simulation results showed that at normal temperature, though the Brownian force can affect the motion of colloids, the attractive force will increase quickly with the distance between colloids down to 12σ , which makes colloids aggregate. When the Brownian force is weak to colloid’s motion, for the enhancement of electric field strength, the DEP force of colloid will increase and so did the attractive force, which finally quickens the aggregate speed. Simulation results also showed that the temperature’ enhancement will increase the Brownian force of colloids, hence disturbing the colloids aggregation. Moreover, the DLVO theory was used to study the motion of a pair of interactional colloids, both the potential energy and the attractive force versus distance of colloids were presented, then the latter graph was used to compare with another graph elicited by MD method. Results showed that the two graphs were nearly the same, indicating the MD model accorded with the theory.

  19. Molecular dynamics simulation for agggregation phenomena of nanocolloids

    Institute of Scientific and Technical Information of China (English)

    NI ZhongHua; ZHANG XinJie

    2009-01-01

    Nonequilibrium molecular dynamics (MD) method was used to study the dielectrophoresis (DEP) mo-tion of nanocolioids in non-uniform electric field. By changing the electric field strength and system temperature, aggregation phenomena of nanocolloids was analyzed. Simulation results showed that at normal temperature, though the Brownian force can affect the motion of colloids, the attractive force will increase quickly with the distance between colloids down to 12 σ, which makes colloids aggregate. When the Brownian force is weak to colloid's motion, for the enhancement of electric field strength, the DEP force of colloid will increase and so did the attractive force, which finally quickens the aggregate speed. Simulation results also showed that the temperature' enhancement will increase the Brownian force of colloids, hence disturbing the colloids aggregation. Moreover, the DLVO theory was used to study the motion of a pair of interactional colloids, both the potential energy and the attractive force versus distance of colloids were presented, then the latter graph was used to compare with another graph elicited by MD method. Results showed that the two graphs were nearly the same, indicating the MD model accorded with the theory.

  20. Investigation of some galactic and extragalactic gravitational phenomena

    Directory of Open Access Journals (Sweden)

    Jovanović P.

    2012-01-01

    Full Text Available Here we present a short overview of the most important results of our investigations of the following galactic and extragalactic gravitational phenomena: supermassive black holes in centers of galaxies and quasars, supermassive black hole binaries, gravitational lenses and dark matter. For the purpose of these investigations, we developed a model of a relativistic accretion disk around a supermassive black hole, based on the ray-tracing method in the Kerr metric, a model of a bright spot in an accretion disk and three different models of gravitational microlenses. All these models enabled us to study physics, spacetime geometry and effects of strong gravity in the vicinity of supermassive black holes, variability of some active galaxies and quasars, different effects in the lensed quasars with multiple images, as well as the dark matter fraction in the Universe. We also found an observational evidence for the first spectroscopically resolved sub-parsec orbit of a supermassive black hole binary system in the core of active galaxy NGC 4151. Besides, we studied applications of one potential alternative to dark matter in the form of a modified theory of gravity on Galactic scales, to explain the recently observed orbital precession of some S-stars, which are orbiting around a massive black hole at the Galactic center. [Projekat Ministarstva nauke Republike Srbije, br. 176003: Gravitation and the Large Scale Structure of the Universe