Science.gov

Sample records for puissance des piles

  1. Interaction puissance-commande au sein des convertisseurs statiques

    NASA Astrophysics Data System (ADS)

    Merienne, F.; Roudet, J.

    1996-06-01

    The electrical energy conversion is increasingly conversion is increasingly used in actual electrical systems. Also, the reduction of energical losses during the energy conversion has become an important objective. Thus, the electronic switch speed has been increased and allowed to reduce losses, but the technological implantation of components induces some electromagnetic compatibility problems. This is the reason of the interest of static converter designers in the Electromagnetic Compatibility. So, the study concerns the different risks of static converter malfunctioning due to its technology. Connections between energical sources (receiver and transmitter) and electronic switches (power unit and control unit) are often constituted of printed circuit traces, wires and copper bars. This connection is not perfect and its parasitic elements can disturb the static converter, even sometimes until its malfunctioning. The proposed study remains qualitative and unfolds in two times. In a first time, malfunctioning causes are shown according to the technology. For each case, risks are evaluated and design rules outlined. In a second time, proposed rules are applied onh a power static DC/DC converter, allowing to improve layout forward a better operating safety. Dans les systèmes électriques actuels, l'électronique de puissance est de plus en plus utilisée pour conditionner l'énergie électrique. Les convertisseurs statiques ont subi une évolution technologique importante notamment pour augmenter leur rendement et leur compacité. Ces performances sont essentiellemnt dues à l'accroissement de la rapidité des interrupteurs électroniques qui permert une réduction des pertes par commutation (absence de circuit d'aide à la commutation) et l'apparition de techniques de câblage nouvelles (hybrides, SMI...). Cependant, l'implantation technologique de ces composants modernes n'est pas sans poser quelques problèmes de compatibilité électromagnétique (perturbations

  2. Qualification sous irradiation du crayon cea: de la conception des composants a l'irradiation d'assemblages en reacteur de puissance

    NASA Astrophysics Data System (ADS)

    Marin, Jean-François; Pillet, Claude; François, Bernard; Morize, Pierre; Petitgrand, Sylvie; Atabek, Rose-Marie; Houdaille, Brigitte

    1982-04-01

    Cet article résume les principaux résultats obtenus au CEA au cours des dix dernières années dans la conception, la qualification et la fabrication des différents éléments originaux constitutifs d'un assemblage de réacteur à eau pressurisée, notamment: l'oxyde UO 2 obtenu par le procédé du Double Cycle Inverse, la gaine en zircaloy 4 recris talllsée, la grille à ressort papillon, la structure à grilles coulissantes. Les etudes et essais hors-pile de comportement thermomécanique du crayon et thermohydraulique des composants de l'assemblage, les irradiations paramétriques de crayons jusqu'à une combustion massique élevée, la validation à partir d'examens aprés irradiation des principaux modèles introduits dans les calculs de conception, enfin l'introduction en réacteur prototype, puis en réacteur de puissance d'assemblages comportant ces différents éléments, constituent les principales étapes de ce développement.

  3. Caractérisation des dégradations de transistors MOS de puissance sous irradiations

    NASA Astrophysics Data System (ADS)

    Bendada, E.; Raïs, K.; Mialhe, P.

    1997-11-01

    The aim of this work is the characterization of D-MOS (HEXFET) structure before and after irradiations. An innovative method for device characterisation is experimented to quantify radiation effects. This study is based on the determination of importants parameters: series resitance, ideality factor, reverse recombination and reverse diffusion currents of the substrate-drain junction by the analysis of its current voltage characteristics. The form of I V characteristics of the substrate-drain junction with operating conditions is found dependent of defects induced by irradiations. It is shown that values of the series resistance, the ideality factor and the reverse recombination current increases with the gate voltage and with the dose absorbed. The reverse diffusion current is shown to be not albered by radiation exposures. Une nouvelle méthode de caractérisation de la dégradation sous irradiations des transistors à structure D-MOS de type HEXFET est proposée. Elle est basée sur l'analyse des propriétés de la diode substrat-drain en utilisant les méthodes bien établies de modélisation des jonctions p-n. La description des caractéristiques courant-tension à l'aide des modèles permettant de séparer les processus de diffusion et de recombinaison des porteurs, conduit à déterminer d'une manière simple des paramètres importants: résistance série, facteur de qualité, courant inverse de recombinaison et courant inverse de diffusion. La forme des caractéristiques courant-tension de la jonction avec les conditions de fonctionnement est trouvée dépendante des défauts induits par les irradiations. Il est montré que les valeurs de la résistance série, du facteur de qualité et du courant inverse de recombinaison augmentent avec la tension de grille et avec la dose absorbée. Le courant inverse de diffusion est non altéré par l'exposition aux radiations.

  4. Phénomènes d'électrisation des matériaux isolants pour transformateurs de puissance

    NASA Astrophysics Data System (ADS)

    Peyraque, L.; Béroual, A.; Boisdon, C.; Buret, F.

    1994-07-01

    In power transformers, the oil flowed through the cooling ducts in coil assembly induces a static charge separation. The study of this static electrification phenomena is presented through a device allowing to investigate the charge separation generated by the rotating motion of a transformer pressboard in oil. This permits to show the influence of various parameters such as velocity, temperature, moisture and processing of oils and pressboards as well as their nature on this electrical charge. We also present another device allowing to classify oils according to their level of charge production. It appears from our results that a correlation exists between the density of these charges and the characteristics of oil such as conductivity, electric strength and water content. Dans les transformateurs de puissance, la circulation d'huile à travers les canaux de refroidissement en fibre cellulosique (carton isolant) est à l'origine d'une séparation de charges. L'étude de ce phénomène d'électrisation statique est présentée, tout d'abord à travers un dispositif permettant d'étudier la séparation de charges créées par le mouvement du carton dans l'huile. Celui-ci a permis de mettre en évidence l'influence de plusieurs paramètres comme la vitesse, la température, l'humidité et le traitement des huiles et cartons ainsi que la nature du carton sur cette charge. Le second dispositif présenté permet de classer les huiles selon leur niveau de création de charges. Une corrélation semble s'établir entre la densité de ces charges et les grandeurs caractéristiques de l'huile telles que la conductivité, la rigidité diélectrique et la teneur en eau.

  5. Incertitude dans les mesures de courant : un obstacle dans la caractérisation des composants en électronique de puissance

    NASA Astrophysics Data System (ADS)

    Farjah, E.; Barbaroux, J.; Perret, R.

    1993-07-01

    The aim of this paper is to clarify the need for the most accurate current measurement applied to the characterization of the power electronic components. The focus is on the behaviour of the normally used high quality high bandwidth current transformers and other sensors to a fast varying high di/dt test current furnished by a new developed test current generator. In this paper after explaining the new strategy of the test generator, different current transformers are tested and characterized and a detailed comparative experimental study is carried out using a non-inductive shunt as the reference. Finally some general remarks and the necessary precautions and different measurement problems are listed and discussed. Le but de cet article est d'essayer de lever les obstacles rencontrés lors des mesures de courant servant à la caractérisation des composants en électronique de puissance. Nous nous sommes penchés sur les différences entre les réponses de quelques capteurs de haute qualité. Après une brève explication du principe d'un générateur de courant de test spécialement conçu pour cette étude, nous comparons les réponses de plusieurs transformateurs de courant par rapport à un shunt aselfique pris pour référence. Enfin nous abordons les différents aspects concernant les précautions qu'il est nécessaire de prendre pour réaliser ce type de mesure.

  6. Commande numérique de moteurs synchrones à aimants permanents de faible puissance

    NASA Astrophysics Data System (ADS)

    Robyns, B.; Fu, Y.; Labrique, F.; Buyse, H.

    1995-08-01

    High performance motion control with permanent magnet synchronous actuators needs complex control strategies. These control strategies lead frequently to algorithms requiring powerful microprocessors for their digital implementation. In this paper, we consider an approach of the control of small power permanent magnets synchronous actuators which allows to design and to implement control algorithms requiring only a reduced computation power, while maintaining satisfactory static and dynamic performance and a good insensitivity to perturbations and parameter uncertainties. L'actionnement électrique à hautes performances par moteurs synchrones à aimants permanents impose des stratégies de commande évoluées liées au comportement dynamique complexe de ces machines. Ces stratégies de commande conduisent fréquemment à des algorithmes dont l'implantation numérique exige des microprocesseurs ayant une puissance de calcul élevée. Dans cet article, nous développons une approche du problème de la commande des moteurs synchrones à aimants permanents de faible puissance qui permet de concevoir et d'implanter des algorithmes de commande ne nécessitant qu'une puissance de calcul réduite, tout en garantissant des performances statiques et dynamiques satisfaisantes ainsi qu'une bonne insensibilité aux perturbations agissant sur le système et aux incertitudes sur les paramètres.

  7. Modélisation par éléments finis 3D du champ magnétostatique dans les enroulements des réactances cuirassées de grande puissance. Comparaison avec le calcul en 2D

    NASA Astrophysics Data System (ADS)

    Ngnegueu, Triomphant; Terme, Claude; Mailhot, Michel

    1993-03-01

    In this paper, the finite element method is applied for the computation of the magnetostatic field in the windings of a shell-form reactor. The modeling is carried out in 3D, using FLUX3D, a software developed at the Laboratoire d'Electrotechnique de Grenoble. The results are compared to those obtained in 2D. These calculation results are also compared to some test results. Dans cet article, nous décrivons une application de la méthode des éléments finis pour la modélisation du champ magnétostatique dans les enroulements d'une réactance cuirassée de grande puissance. La modélisation est conduite en 3D, en utilisant le logiciel FLUX3D. Les résultats du calcul sont comparés avec ceux obtenus en 2D. Quelques comparaisons sont aussi effectuées avec des résultats de mesure.

  8. Commande numérique simplifiée et robuste d'actionneurs asynchrones de faible puissance

    NASA Astrophysics Data System (ADS)

    Robyns, B.; Labrique, F.; Buyse, H.

    1996-08-01

    High performance motion control with AC actuators needs complex control strategies. The control strategies lead frequently to algorithms requiring powerful microprocessors for their digital implementation. In a previous paper published in the “Journal de Physique III”, we evolved an approach of the control of small power permanent magnets synchronous actuators which allows to design and to implement control algorithms requiring only a reduced computation power, while maintaining satisfactory static and dynamic performance and a good insensitivity to perturbations and parameter uncertainties. In this paper, we extend this approach to the control of small power induction actuators. L'actionnement électriques à hautes performances au moyen de moteurs à courant alternatif impose des stratégies de commande évoluées liées au comportement dynamique complexe de ces machines. Ces stratégies de commande conduisent fréquemment à des algorithmes dont l'implantation numérique exige des microprocesseurs ayant une puissance de calcul élevée. Dans un précédent article publié dans le Journal de Physique III, nous avons développé une approche du problème de la commande des moteurs synchrones à aimants permanents de faible puissance qui nous a permis de concevoir et d'implanter des algorithmes de commande ne nécessitant qu'une puissance de calcul réduite, tout en garantissant des performances statiques et dynamiques satisfaisantes ainsi qu'une bonne insensibilité aux perturbations agissant sur le système et aux incertitudes sur les paramètres. Dans cet article, nous étendons cette approche au cas de la commande des moteurs asynchrones de faible puissance.

  9. Big Pile or Small Pile?

    ERIC Educational Resources Information Center

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-01-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece…

  10. Pile Driving

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  11. Big Pile or Small Pile?

    NASA Astrophysics Data System (ADS)

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-10-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece of fruit to produce a low-intensity electrical current to power a digital device. In a voltaic pile of this type, the zinc acts as an anode while the copper acts as a cathode. The reduction reaction [i.e.,2H+(aq)+2e⇋H2(g)] occurs on the copper (the cathode). The two electrons that are needed for the reduction are taken from the metal (copper), which remains positively charged, while the anode is the zinc, which is oxidized through the reaction Zn∘(m)⇋Zn+2(aq )+2e, and the two electrons remain on the metal, which is negatively charged. If the two pieces of metal are connected by an external conductor, electrons flow from the zinc to the copper. The electromotive force of this system is about 0.76 V, which is the reduction potential of zinc, as can be found in the table of standard reduction potentials.

  12. Modélisation de la puissance triphasée contrôlée de façon discrète: application au chauffage industriel

    NASA Astrophysics Data System (ADS)

    Piel, A.; Protin, L.

    1998-04-01

    This paper suggests a method to characterize the three-phase instantaneous power wave for an industrial heating approach using several three-phase converters. To obtain a global behaviour of this plant when the control is assumed by the means of full wave trains using minimal period (discrete control calling syncop mode), different three-phase power modelling methods are submitted. From the computed converter control signals, an associated rebuilding procedure of the three-phase instantaneous power allows to simulate and characterize performances of these industrial-heating systems. Simulation results validated by experimental tests allow envisaging the global strategy development minimising fluctuations of the instantaneous three-phase power. L'article propose, pour l'étude des chauffages industriels mettant en jeu plusieurs gradateurs triphasés, une méthode de caractérisation de l'onde de la puissance instantanée triphasée. Dans le cas d'un fonctionnement en trains d'onde à période minimale (commande discrète dite syncopée) et afin de rendre compte du comportement global d'un ensemble comportant plusieurs gradateurs, différentes modélisations de l'onde triphasée sont envisagées. Une fois établi le concept de la modélisation, et à partir de signaux de commande élaborés logiciellement, une procédure de reconstruction de l'onde de puissance associée à chaque gradateur permet de simuler et de caractériser les performances de ces systèmes de chauffage industriel. Les résultats de simulation validés par des essais expérimentaux permettent d'envisager la mise au point de stratégies globales minimisant les fluctuations de la puissance triphasée instantanée.

  13. A Pile of Legos.

    ERIC Educational Resources Information Center

    DePino, Andrew, Jr.

    1994-01-01

    Describes the relationships a high school built with neighborhood industry, a national laboratory, a national museum, and a large university while trying to build a scale model of the original atomic pile. Provides suggestions for teachers. (MVL)

  14. A simplified analysis method for piled raft and pile group foundations with batter piles

    NASA Astrophysics Data System (ADS)

    Kitiyodom, Pastsakorn; Matsumoto, Tatsunori

    2002-11-01

    A simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to vertical, lateral, and moment loads, using a hybrid model in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. Both the vertical and lateral resistances of the piles as well as the raft base are incorporated into the model. Pile-soil-pile, pile-soil-raft and raft-soil-raft interactions are taken into account based on Mindlin's solutions for both vertical and lateral forces. The validity of the proposed method is verified through comparisons with several existing methods for single piles, pile groups and piled rafts. Workable design charts are given for the estimation of the lateral displacement and the load distribution of piled rafts from the stiffnesses of the raft alone and the pile group alone. Additionally, parametric studies were carried out concerning batter pile foundations. It was found that the use of batter piles can efficiently improve the deformation characteristics of pile foundations subjected to lateral loads.

  15. Flexible pile thermal barrier insulator

    NASA Technical Reports Server (NTRS)

    Anderson, G. E.; Fell, D. M.; Tesinsky, J. S. (Inventor)

    1978-01-01

    A flexible pile thermal barrier insulator included a plurality of upstanding pile yarns. A generally planar backing section supported the upstanding pile yarns. The backing section included a plurality of filler yarns forming a mesh in a first direction. A plurality of warp yarns were looped around said filler yarns and pile yarns in the backing section and formed a mesh in a second direction. A binder prevented separation of the yarns in the backing section.

  16. Piled Embankment Design Comparison

    NASA Astrophysics Data System (ADS)

    Drusa, Marián; Kais, Ladislav; Vlček, Jozef; Mečár, Martin

    2015-05-01

    There are currently several national standards or regulations for the design of the piled embankment, providing suitable solutions for foundation of transport structure on soft, high compressible subsoil, [1]. The most widely used and the best-known standard is British Standard BS8006 [2], which was confronted with another analytical design methodologies (Ebgeo, CUR). Today's popularity and versatility of FEM numerical models brings many advantages, which analytical methods cannot achieved, but must be verified by proposed scaled physical model, which was currently being developed by Department of Geotechnics, University of Žilina.

  17. Test Pile Reactivity Loss Due to Trichloroethylene

    SciTech Connect

    Plumlee, K.E.

    2001-03-09

    The presence of trichloroethylene in the test pile caused a continual decrease in pile reactivity. A system which removed, purified, and returned 12,000 cfh helium to the pile has held contamination to a negligible level and has permitted normal pile operation.

  18. Pullout capacity of batter pile in sand.

    PubMed

    Nazir, Ashraf; Nasr, Ahmed

    2013-03-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21-31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18-75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted.

  19. Pullout capacity of batter pile in sand

    PubMed Central

    Nazir, Ashraf; Nasr, Ahmed

    2012-01-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21–31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18–75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted. PMID:25685412

  20. Conception et analyse de combineurs spatiaux de puissance pour des applications d'amplification et de multiplication de frequences

    NASA Astrophysics Data System (ADS)

    Belaid, Mekki

    MMIC devices experience a remarkable development nowadays. They make it possible to obtain unequalled performances compared to vacuum electronic devices. Until approximately 12 GHz, binary networks make it possible to combine in an effective way a great number of devices. Beyond 12 GHz, combining MMIC devices by using a binary network quickly becomes ineffective when the number of devices to be combined increases. The various techniques of spatial power combining allow, in a remarkable way, to overcome this handicap by offering a solution which makes it possible to obtain a very great combining efficiency for a great number of devices. The first solutions which were studied used a topology called the tile tray approach which consisted of a grid of active elements that is positioned perpendicularly to the propagation direction of the incident wave. The amplified signal is emitted on the other side of the grid or in the same side but with a perpendicular polarisation to the incidental signal. The second approach, called tray array, consists in placing the elements in the direction to find incidental wave. This new approach consisted of using a Quasi-TEM propagating mode inside the rectangular waveguide instead of the TE10 mode. To obtain the Quasi-TEM mode, frequency selective surfaces called UC-EBG were used on the two sides of the rectangular waveguide. This technique made it possible to improve considerably the performances of amplifier SPCA making the combined efficiency structure passes from 70% to 85%. The same approach was also used to design a new structure which makes it possible to combine frequency multipliers. The structure consisted of the combination of four MMIC frequency multipliers operating in the frequency band at the input between 11 and 13 GHz and at its output between 22 and 26 GHz. Not only an increase in the output power was observed with a combining efficiency of 70% but suppression of the first and third harmonics were eliminated respectively by at least 70 dBc and 20 dBc without the addition of any filter. Suppression of the harmonics is done naturally thanks to the configuration of the structure. (Abstract shortened by UMI.)

  1. Static and dynamic pile testing of reinforced concrete piles with structure integrated fibre optic strain sensors

    NASA Astrophysics Data System (ADS)

    Schilder, Constanze; Kohlhoff, Harald; Hofmann, Detlef; Basedau, Frank; Habel, Wolfgang R.; Baeßler, Matthias; Niederleithinger, Ernst; Georgi, Steven; Herten, Markus

    2013-05-01

    Static and dynamic pile tests are carried out to determine the load bearing capacity and the quality of reinforced concrete piles. As part of a round robin test to evaluate dynamic load tests, structure integrated fibre optic strain sensors were used to receive more detailed information about the strains along the pile length compared to conventional measurements at the pile head. This paper shows the instrumentation of the pile with extrinsic Fabry-Perot interferometers sensors and fibre Bragg gratings sensors together with the results of the conducted static load test as well as the dynamic load tests and pile integrity tests.

  2. Pile Spacing Optimization of Short Piled Raft Foundation System for Obtaining Minimum Settlement on Peat

    NASA Astrophysics Data System (ADS)

    Suro, S. M.; Bakar, I.; Sulaeman, A.

    2016-07-01

    Short Piled Raft is a modified piled raft foundation system, which represents combination between raft foundation and pile foundation, but the length of pile is relatively shorter. The basic concept of the Short Piled Raft foundation system considers the passive soil pressure creating a stiff condition of slab-pile system. This means that the thin concrete slab floats on the supporting soil, while the piles serve as stiffeners concrete slab and also to reduce settlement of the foundation. Slab to pile ratio of such system has been mentioned by several researchers, however the optimum pile spacing of stability performance for obtaining minimum settlement on peat haven't been clearly discussed. In this study, finite element method to simulate the stability performance related to settlement of Short Piled Raft foundation system was used. Short Piled Raft foundation system with concrete slab of 7.0 m x 7.0 m square was assumed to be built on peat with the thickness of 3.5 m. The material properties of pile and raft were constant. The outer diameter of galvanized steel pipe as pile was 0.30 m; raft thickness was considered to be constant of 0.15 m and the length of pile was 3.0 m, while the pile spacing varied from 0.50 to 3.00 m. Point load varied from 0 to 100 kN with increment of 20 kN was also considered as a static load, acted on the centre of the concrete slab. Optimization was done by comparing each numerical result of simulations, thus conclusion can easily be drawn. The optimum pile spacing was 1.00 m which produced minimum settlement of 30.11 mm under the load of 100 kN.

  3. Crazy heart: kinematics of the "star pile" in Abell 545

    NASA Astrophysics Data System (ADS)

    Salinas, R.; Richtler, T.; West, M. J.; Romanowsky, A. J.; Lloyd-Davies, E.; Schuberth, Y.

    2011-04-01

    We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster. We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution. Based on observations taken at the European Southern Observatory, Cerro Paranal, Chile, under programme ID 080.B-0529. Also based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and SECYT (Argentina); and on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National

  4. Underwater Sound Propagation from Marine Pile Driving.

    PubMed

    Reyff, James A

    2016-01-01

    Pile driving occurs in a variety of nearshore environments that typically have very shallow-water depths. The propagation of pile-driving sound in water is complex, where sound is directly radiated from the pile as well as through the ground substrate. Piles driven in the ground near water bodies can produce considerable underwater sound energy. This paper presents examples of sound propagation through shallow-water environments. Some of these examples illustrate the substantial variation in sound amplitude over time that can be critical to understand when computing an acoustic-based safety zone for aquatic species.

  5. Methodes iteratives paralleles: Applications en neutronique et en mecanique des fluides

    NASA Astrophysics Data System (ADS)

    Qaddouri, Abdessamad

    Dans cette these, le calcul parallele est applique successivement a la neutronique et a la mecanique des fluides. Dans chacune de ces deux applications, des methodes iteratives sont utilisees pour resoudre le systeme d'equations algebriques resultant de la discretisation des equations du probleme physique. Dans le probleme de neutronique, le calcul des matrices des probabilites de collision (PC) ainsi qu'un schema iteratif multigroupe utilisant une methode inverse de puissance sont parallelises. Dans le probleme de mecanique des fluides, un code d'elements finis utilisant un algorithme iteratif du type GMRES preconditionne est parallelise. Cette these est presentee sous forme de six articles suivis d'une conclusion. Les cinq premiers articles traitent des applications en neutronique, articles qui representent l'evolution de notre travail dans ce domaine. Cette evolution passe par un calcul parallele des matrices des PC et un algorithme multigroupe parallele teste sur un probleme unidimensionnel (article 1), puis par deux algorithmes paralleles l'un mutiregion l'autre multigroupe, testes sur des problemes bidimensionnels (articles 2--3). Ces deux premieres etapes sont suivies par l'application de deux techniques d'acceleration, le rebalancement neutronique et la minimisation du residu aux deux algorithmes paralleles (article 4). Finalement, on a mis en oeuvre l'algorithme multigroupe et le calcul parallele des matrices des PC sur un code de production DRAGON ou les tests sont plus realistes et peuvent etre tridimensionnels (article 5). Le sixieme article (article 6), consacre a l'application a la mecanique des fluides, traite la parallelisation d'un code d'elements finis FES ou le partitionneur de graphe METIS et la librairie PSPARSLIB sont utilises.

  6. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  7. Effects of Lateral Loads on a Single Pile

    NASA Astrophysics Data System (ADS)

    Phanikanth, V. S.; Choudhury, D.

    2012-09-01

    Design of piles under lateral loads requires estimation of ultimate load carrying capacity of the pile and also, the pile deflections need to be evaluated to determine the allowable loads. For estimating the pile response, structural engineers invariably utilize the simplified method prescribed in the Indian code IS 2911-2002 (Indian Standard Code of Practice for Design of Pile Foundations, 2002). The method is based on replacing the pile soil system by an equivalent cantilever, the length of which is a function of subgrade reaction of the surrounding soil and the pile geometry. However, the method described is applicable only for flexible piles, where the maximum depth coefficient L/ T is equal to or exceeds 4.0. To estimate the pile response for rigid piles, simplified procedures are not suggested and hence in the present study, an attempt has been made to evaluate the pile response under lateral loads using detailed soil-pile analysis. Parametric studies are carried out for various pile lengths and various soil stiffness. The pile responses thus obtained are compared with the method given in IS 2911-2002. It was observed that the pile response based on IS 2911-2002 compared reasonably well with the detailed soil-pile model even for L/ T ≥ 2.5. However IS 2911-2002 underestimates the pile head deflections for L/ T < 2.5 for both free headed and fixed head piles and hence detailed soil-pile analysis is essential for such situations. The variation of pile response with soil stiffness is also evaluated using these methods and the results are presented. The soil-pile analysis is carried out using subgrade modulus approach. The soil stiffness is assumed to vary linearly along the pile depth and hence the study is applicable for cohesionless soils which can be used for practical design of single pile subjected to lateral loads.

  8. Inhomogeneites dans le Vent des Etoiles Wolf-Rayet

    NASA Astrophysics Data System (ADS)

    Robert, Carmelle

    1992-01-01

    autres, une correlation entre le nombre d'inhomogeneites detectees et la vitesse terminale. Cette relation explique bien l'anti-correlation observee entre le niveau de variabilite spectroscopique, photometrique ou polarimetrique et la vitesse terminale. On estime pour toutes les etoiles une masse moyenne des inhomogeneites de 7 times 10^{ -10} Modot et un taux de perte de masse sous la forme d'inhomogeneites detectables qui correspond a 10% de la perte de masse du vent total. L'histogramme du nombre d'inhomogeneites en fonction du leur flux pourrait cependant predire l'existence d'un grand nombre de petites structures non-detectees ici a cause du rapport signal sur bruit relativement trop faible. Ce resultat interessant, qui demande cependant a etre verifie, suggere que le vent pourrait etre forme d'un ensemble quasi infini d'inhomogeneites. En ajustant une loi de puissance dans l'histogramme du flux de chaque etoile, on calcule, pour les plus grosses structures, un exposant = -2.4 +/- 0.2. On constate alors que cette valeur est compatible avec celle que predit la turbulence supersonique. Les structures observees dans les spectres des etoiles WR ont des caracteristiques tres semblables a celles des etoiles O. On propose alors que les perturbations observees chez ces 2 types d'etoiles ont une meme origine. Parmi les mecanismes deja proposes dans le passe pour expliquer les variations des etoiles O et WR (instabilites radiatives, pulsations et champ magnetique) on ne saurait encore dire <=uel, ou lesquels, correspondent le mieux aux observations. Dans les projets futurs, on propose de considerer aussi le role que pourrait avoir la turbulence pour expliquer les perturbations du vent stellaire.

  9. Nonlinear Seismic Response Of Single Piles

    SciTech Connect

    Cairo, R.; Conte, E.; Dente, G.

    2008-07-08

    In this paper, a method is proposed to analyse the seismic response of single piles under nonlinear soil condition. It is based on the Winkler foundation model formulated in the time domain, which makes use of p-y curves described by the Ramberg-Osgood relationship. The analyses are performed referring to a pile embedded in two-layer soil profiles with different sharp stiffness contrast. Italian seismic records are used as input motion. The calculated bending moments in the pile are compared to those obtained using other theoretical solutions.

  10. 116. Photocopied August 1978. NEW INTERLOCKING STEEL SHEET PILING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    116. Photocopied August 1978. NEW INTERLOCKING STEEL SHEET PILING AT PENSTOCK 52 IN THE FALL OF 1926. THE PILES FOR SUPPORTING THE HORIZONTAL ELEMENTS OF THE NEW FOREBAY APRON ARE IN PLACE BETWEEN THE NEW SHEET PILING AND THE FOREBAY WALL. VISIBLE BEYOND THE NEW SHEET PILING IS THE TIMBER SHEET PILING DRIVEN IN 1903 BY VON SCHON TO PREVENT WASHOUTS. (1006) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  11. Grouting of uranium mill tailings piles

    SciTech Connect

    Boegly, W.J. Jr.; Tamura, T.; Williams, J.D.

    1984-03-01

    A program of remedial action was initiated for a number of inactive uranium mill tailings piles. These piles result from mining and processing of uranium ores to meet the nation's defense and nuclear power needs and represent a potential hazard to health and the environment. Possible remedial actions include the application of covers to reduce radon emissions and airborne transport of the tailings, liners to prevent groundwater contamination by leachates from the piles, physical or chemical stabilization of the tailings, or moving the piles to remote locations. Conventional installation of liners would require excavation of the piles to emplace the liner; however, utilization of grouting techniques, such as those used in civil engineering to stabilize soils, might be a potential method of producing a liner without excavation. Laboratory studies on groutability of uranium mill tailings were conducted using samples from three abandoned piles and employing a number of particulate and chemical grouts. These studies indicate that it is possible to alter the permeability of the tailings from ambient values of 10/sup -3/ cm/s to values approaching 10/sup -7/ cm/s using silicate grouts and to 10/sup -8/ cm/s using acrylamide and acrylate grouts. An evaluation of grouting techniques, equipment required, and costs associated with grouting were also conducted and are presented. 10 references, 1 table.

  12. Lateral load tests on large pipe piles in coral

    SciTech Connect

    Vines, W.R.; Hong, I.S.

    1984-05-01

    Results are presented for lateral load tests on 36-, 48-, 80-, and 132-in. diameter pipe piles in 26- to 67-ft water depths at a port site in Saudi Arabia. Primary soil types at the site are crushed coral and sand, with layers of intact weak coral. Pile loads were measured with load cells, deflections were measured with potentiometers, and pile slopes were measured with a slope indicator. Pile top deflections and pile deflected shapes are reported at several load levels. Maximum test loads ranged from 72 to 559 kips, and maximum pile top deflections were from 3.6 to 55 inches. Comparison of test results to expectations of behavior based on state-of-the-practice analytical methods shows that the character of pile deflected shapes were predicted well, but that deflections were generally over-predicted in the analyses. Comparison of test pile and reaction pile deflected shapes shows secondary but significant differences.

  13. Comportement des piles de ponts sous l'effet multidirectionnel des mouvements sismiques

    NASA Astrophysics Data System (ADS)

    Khaled, Amar

    A comprehensive study has been conducted to investigate the seismic behaviour of bridge columns under bidirectional earthquake ground motions. The study comprises a series of linear elastic and non-linear dynamic analyses on a set of regular bridge structures representative of common type bridges that are encountered the most in North American highways, as well as bidirectional cyclic testing of four half-scale rectangular reinforced concrete bridge columns. The first part of the study was aimed at investigating the adequacy and effectiveness of the 30%- rule, at predicting the seismic demand on bridge columns when subjected to bi-directional earthquake motions. A series of multiple time-history analyses performed on nine generic bridge models to determine the exact seismic critical bi-axial response of the bridge columns under pairs of orthogonal seismic ground motion time-histories. Response spectrum analyses were also carried out, using the acceleration spectra of the orthogonal ground motion components, to determine the maximum bi-axial response in each direction and the critical bi-axial response was estimated using the 30%-Rule, as specified by the CSA S6 and the AASHTO bridge design code and regulations. In the second part of the study, a new Percentage Rule for the prediction of interacting seismic responses of bridge columns under multi-directional earthquake components is derived for the two sites. A total of 14 regular bridges with different geometrical properties were examined for the two sites. The new rule was developed by comparing the column longitudinal steel ratio required from response spectrum analysis with combination rules to the ratio determined from the results of multiple linear dynamic time history analysis of the bridge structures under bidirectional ground motions. The steel ratios were computed for the bending moment demand from response spectrum analysis using the combination rule with different values of the weighted percentage alpha (0, 0.3, and 1.0) and the skew angle (10° to 45°). These ratios were compared to those obtained from multiple elastic time history analyses to identify the bridge properties that influence the most the combination rule. In this last part of the study, the need for combination rules to account for seismic demand from the simultaneous action of bidirectional horizontal ground motion earthquake components and the current CSA S6 requirements regarding the lower limit of 0.8% on the longitudinal reinforcement ratio and the transverse reinforcement for confinement for bridge columns were examined through bidirectional cyclic tests on four identical half-scale reinforced concrete rectangular bridge column specimens. The prototype structures are regular common two-span, skewed bridge structures designed according to CSA S6-06, and the study focused on the demand from earthquakes expected in Eastern and Western Canada. The column specimens are 1.2 m x 0.6 m in cross-section and 3.0 m tall, with axial loads varying between 4.5 to 9.3% Agf'c. Two specimens were designed for Montreal, QC, Canada (east site) using 0% and 30% combination rules, resulting in longitudinal steel ratios of 0.41% and 0.57%. Two specimens represented columns part of bridges located in Vancouver, BC, Canada (west site), with longitudinal steel ratios of 0.97% and 1.72% resulting from the application of 0% and 40% combination rules. Site specific cyclic displacement test protocols were developed from time history analysis of the bridge structures that were previously performed in the second part of the study. All columns exhibited satisfactory inelastic cyclic bidirectional response up to high ductility levels. For both sites, the Combination Rules used in design had no significant influence on the inelastic cyclic response of the columns. The columns designed for the Montreal site exhibited satisfactory inelastic cyclic performance even if they had longitudinal reinforcement ratio less than the current CSA S6 limit of 0.8%. Buckling and rupture of corner bars were however observed at high ductility levels in two specimens, showing the need for additional restraint for these bars and more stringent requirements for transverse reinforcement in columns subjected to bi-axial loading. For all specimens, the height of the plastic hinge region was approximately equal to the smaller column dimension, rather than the larger one as currently specified in CSA S6. (Abstract shortened by UMI.)

  14. 6. CANNERY PILINGS Foundation of a portion of the cannery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. CANNERY PILINGS Foundation of a portion of the cannery over water. Crumbling cement footings and decomposing pilings make portions of this area unsafe. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  15. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  16. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  17. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  18. 30 CFR 77.209 - Surge and storage piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the...

  19. 30 CFR 77.209 - Surge and storage piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the...

  20. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Refuse piles; abandonment. 77.215-4 Section 77.215-4 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be...

  1. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Refuse piles; abandonment. 77.215-4 Section 77.215-4 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be...

  2. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Refuse piles; abandonment. 77.215-4 Section 77.215-4 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be...

  3. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; abandonment. 77.215-4 Section 77.215-4 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be...

  4. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Refuse piles; abandonment. 77.215-4 Section 77.215-4 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be...

  5. 30 CFR 77.215-1 - Refuse piles; identification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; identification. 77.215-1 Section... COAL MINES Surface Installations § 77.215-1 Refuse piles; identification. A permanent identification marker, at least six feet high and showing the refuse pile identification number as assigned by...

  6. 30 CFR 77.215-3 - Refuse piles: certification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles: certification. 77.215-3 Section... COAL MINES Surface Installations § 77.215-3 Refuse piles: certification. (a) Within 180 days following written notification by the District Manager that a refuse pile can present a hazard, the person...

  7. 30 CFR 77.209 - Surge and storage piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the...

  8. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the... removed from the disposal area prior to placement of coal mine waste. Topsoil shall be removed,...

  9. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the... removed from the disposal area prior to placement of coal mine waste. Topsoil shall be removed,...

  10. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the... removed from the disposal area prior to placement of coal mine waste. Topsoil shall be removed,...

  11. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of...

  12. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of...

  13. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of...

  14. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of...

  15. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of...

  16. 30 CFR 77.215-1 - Refuse piles; identification.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... marker, at least six feet high and showing the refuse pile identification number as assigned by the... specified in paragraphs (a) or (b) of this section as applicable. (a) For existing refuse piles, markers shall be placed before May 1, 1976. (b) For new or proposed refuse piles, markers shall be placed...

  17. 30 CFR 77.215-1 - Refuse piles; identification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... marker, at least six feet high and showing the refuse pile identification number as assigned by the... specified in paragraphs (a) or (b) of this section as applicable. (a) For existing refuse piles, markers shall be placed before May 1, 1976. (b) For new or proposed refuse piles, markers shall be placed...

  18. 30 CFR 77.215-1 - Refuse piles; identification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... marker, at least six feet high and showing the refuse pile identification number as assigned by the... specified in paragraphs (a) or (b) of this section as applicable. (a) For existing refuse piles, markers shall be placed before May 1, 1976. (b) For new or proposed refuse piles, markers shall be placed...

  19. 30 CFR 77.215-1 - Refuse piles; identification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... marker, at least six feet high and showing the refuse pile identification number as assigned by the... specified in paragraphs (a) or (b) of this section as applicable. (a) For existing refuse piles, markers shall be placed before May 1, 1976. (b) For new or proposed refuse piles, markers shall be placed...

  20. Simulation de la formabilite des alliages d'aluminium AA5754 et AA6063

    NASA Astrophysics Data System (ADS)

    Eljaafari, Samira

    Les besoins de reduction du poids se sont concretement traduits par l'introduction de nouvelles nuances plus legeres dans les structures automobiles. Ainsi, des alliages d'aluminium ont commence a etre integres dans les pieces de structure de plusieurs vehicules. La faible masse volumique des alliages d'aluminium (2,7g/cm3) permet d'alleger le poids du vehicule qui entraine une diminution de la consommation de carburant et, donc, des emissions de gaz a effet de serre. La striction et la rupture sont les principaux modes de defaillance qui entrainent le rebut systematique des pieces. C'est pourquoi, ameliorer la prediction d'apparition de ces defauts lors de la simulation va dans le sens d'une meilleure maitrise du procede. Dans le cadre de ce travail doctoral, deux modeles sont developpes pour simuler le comportement a grandes deformations d'alliages d'aluminium: un modele polycristallin de type Taylor et un modele a un ou plusieurs elements finis par grain. Les diagrammes limites de formage (DLF) pour les deux alliages d'aluminium AA5754 et AA6063 ont ete simules numeriquement en utilisant une formulation par elements finis pour les polycristaux basee sur l'hypothese de Taylor. Les DLF conventionnels et de l'hydroformage ont ete traces. L'effet des chemins de deformation sur la formabilite des alliages d'aluminium a aussi ete etudie. Finalement, des simulations numeriques avec les donnees de diffraction des electrons retrodiffuses (EBSD) pour 1'alliage d'aluminium AA5754 ont ete effectuees en utilisant le modele a un ou plusieurs elements par grain. Ces simulations sont executees avec differents modeles du durcissement (Asaro, Bassani et puissance). Mots-cles: Formabilite; Alliage d'aluminium; Hydroformage; Glissement cristallographique; Durcissement; Calcul parallele; Diagramme limite de formage (DLF); Diffraction electron.

  1. Argonne nuclear pioneers: Chicago Pile 1

    SciTech Connect

    Agnew, Harold; Nyer, Warren

    2012-01-01

    On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day.

  2. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Technological Requirements (MTR)? No. Placing hazardous remediation wastes into a staging pile does not constitute land disposal of hazardous wastes or create a unit that is subject to the minimum technological... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS...

  3. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Technological Requirements (MTR)? No. Placing hazardous remediation wastes into a staging pile does not constitute land disposal of hazardous wastes or create a unit that is subject to the minimum technological... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS...

  4. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Technological Requirements (MTR)? No. Placing hazardous remediation wastes into a staging pile does not constitute land disposal of hazardous wastes or create a unit that is subject to the minimum technological... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS...

  5. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Technological Requirements (MTR)? No. Placing hazardous remediation wastes into a staging pile does not constitute land disposal of hazardous wastes or create a unit that is subject to the minimum technological... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS...

  6. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Technological Requirements (MTR)? No. Placing hazardous remediation wastes into a staging pile does not constitute land disposal of hazardous wastes or create a unit that is subject to the minimum technological... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS...

  7. Argonne nuclear pioneers: Chicago Pile 1

    ScienceCinema

    Agnew, Harold; Nyer, Warren

    2016-07-12

    On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day.

  8. Etude theorique et experimentale des evaporateurs de dioxyde de carbone operant dans des conditions de givrage

    NASA Astrophysics Data System (ADS)

    Bendaoud, Adlane Larbi

    . Dans la partie theorique, un modele traitant les aspects thermique, hydrodynamique et massique a ete elabore. Sur la base de ce modele a ete ecrit un programme informatique en langage FORTRAN 6.6. Il est base sur la discretisation du serpentin en volumes de controle, est entierement automatise et peut traiter des echangeurs de chaleur avec des circuits de refrigerant complexes pouvant avoir des entrees et sorties multiples ainsi que des bifurcations. La presence simultanee des trois phases thermodynamiques du refrigerant (liquide sous refroidi, fluide sature, vapeur surchauffee) dans le serpentin est aussi prise en charge. Le modele a ete valide pour un fonctionnement avec et sans formation de givre en utilisant des donnees experimentales disponibles dans la litterature et celles obtenues sur le banc d'essai de CanmetENERGIE. Celui-ci a ete mis a jour pour les besoins de la presente recherche et pour cela, un systeme de surchauffe et d'injection de la vapeur d'eau dans une enceinte a tres basse temperature a ete dimensionne, fabrique et installe. Un dispositif de visualisation de la formation de givre, ainsi qu'un equipement de mesure de la temperature, de la pression et de l'humidite relative de l'air ont aussi ete ajoutes. Une fois le modele valide, des simulations numeriques sur le serpentin avec et sans formation de givre ont ete effectuees. Un premier cas de base a servi comme reference pour d'autres cas pour lesquels une etude parametrique sur la geometrie et le fonctionnement a ete menee. Il a ete montre par rapport au cas de base que : 1. la diminution de la densite des ailettes sur des rangees specifiques du serpentin donne une surface minimale (Amin) plus grande, retardant ainsi l'obstruction totale du serpentin par le givre et permet donc un temps de fonctionnement plus grand et une frequence de degivrage plus faible. 2. une bonne configuration de circuit de refrigerant augmente le temps de fonctionnement du serpentin de 200 % et delivre une puissance

  9. Numerical analysis of kinematic soil-pile interaction

    SciTech Connect

    Castelli, Francesco; Maugeri, Michele; Mylonakis, George

    2008-07-08

    In the present study, the response of singles pile to kinematic seismic loading is investigated using the computer program SAP2000. The objectives of the study are: (1) to develop a numerical model that can realistically simulate kinematic soil-structure interaction for piles accounting for discontinuity conditions at the pile-soil interface, energy dissipation and wave propagation; (2) to use the model for evaluating kinematic interaction effects on pile response as function of input ground motion; and (3) to present a case study in which theoretical predictions are compared with results obtained from other formulations. To evaluate the effects of kinematic loading, the responses of both the free-field soil (with no piles) and the pile were compared. Time history and static pushover analyses were conducted to estimate the displacement and kinematic pile bending under seismic loadings.

  10. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  11. Picking up Clues from the Discard Pile

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil.

    On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through red, green and blue filters that have been combined into this approximately true-color image.

    This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench.

    Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches.

    For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench.

    The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif

  12. Are cometary nuclei primordial rubble piles?

    NASA Technical Reports Server (NTRS)

    Weissman, P. R.

    1986-01-01

    Whipple's icy conglomerate model for the cometary nucleus has had considerable sucess in explaining a variety of cometary phenomena such as gas production rates and nongravitational forces. However, as discussed here, both observational evidence and theoretical considerations suggest that the cometary nucleus may not be a well-consolidated single body, but may instead be a loosely bound agglomeration of smaller fragments, weakly bonded and subject to occasional or even frequent disruptive events. The proposed model is analogous to the 'rubble pile' model suggested for the larger main-belt asteroids, although the larger cometary fragments are expected to be primordial condensations rather than collisionally derived debris as in the asteroid case. The concept of cometary nuclei as primordial rubble piles is proposed as a modification of the basic Whipple model, not as a replacement for it.

  13. Comparaison de méthodes d'identification des paramètres d'une machine asynchrone

    NASA Astrophysics Data System (ADS)

    Bellaaj-Mrabet, N.; Jelassi, K.

    1998-07-01

    Interests, in Genetic Algorithms (G.A.) expands rapidly. This paper consists initially to apply G.A. for identifying induction motor parameters. Next, we compare the performances with classical methods like Maximum Likelihood and classical electrotechnical methods. These methods are applied on three induction motors of different powers to compare results following a set of criteria. Les algorithmes génétiques sont des méthodes adaptatives de plus en plus utilisée pour la résolution de certains problèmes d'optimisation. Le présent travail consiste d'une part, à mettre en œuvre un A.G sur des problèmes d'identification des machines électriques, et d'autre part à comparer ses performances avec les méthodes classiques tels que la méthode du maximum de vraisemblance et la méthode électrotechnique basée sur des essais à vides et en court-circuit. Ces méthodes sont appliquées sur des machines asynchrones de différentes puissances. Les résultats obtenus sont comparés selon certains critères, permettant de conclure sur la validité et la performance de chaque méthode.

  14. Polyhedron Modeling of Rubble-Pile Asteroids

    NASA Technical Reports Server (NTRS)

    Korycansky, D. G.; Asphaug, E.

    2005-01-01

    We report on progress in modeling of asteroids as collections of rigid polyhedra ("rubble piles"). Such models are (idealized) candidates for asteroid structures: aggregates of irregular rocky subunits that are held together by self-gravity and friction. We have taken several steps toward greater realism and physical interest in construction of the models (although the gravitational fields are being treated in a simplified manner). -

  15. Morphological clues to wet granular pile stability.

    PubMed

    Scheel, M; Seemann, R; Brinkmann, M; Di Michiel, M; Sheppard, A; Breidenbach, B; Herminghaus, S

    2008-03-01

    When a granular material such as sand is mixed with a certain amount of liquid, the surface tension of the latter bestows considerable stiffness to the material, which enables, for example, sand castles to be sculpted. The geometry of the liquid interface within the granular pile is of extraordinary complexity and strongly varies with the liquid content. Surprisingly, the mechanical properties of the pile are largely independent of the amount of liquid over a wide range. We resolve this puzzle with the help of X-ray microtomography, showing that the remarkable insensitivity of the mechanical properties to the liquid content is due to the particular organization of the liquid in the pile into open structures. For spherical grains, a simple geometric rule is established, which relates the macroscopic properties to the internal liquid morphologies. We present evidence that this concept is also valid for systems with non-spherical grains. Hence, our results provide new insight towards understanding the complex physics of a large variety of wet granular systems including land slides, as well as mixing and agglomeration problems. PMID:18264104

  16. Response of shallow geothermal energy pile from laboratory model tests

    NASA Astrophysics Data System (ADS)

    Marto, A.; Amaludin, A.

    2015-09-01

    In shallow geothermal energy pile systems, the thermal loads from the pile, transferred and stored in the soil will cause thermally induced settlement. This factor must be considered in the geotechnical design process to avoid unexpected hazards. Series of laboratory model tests were carried out to study the behaviour of energy piles installed in kaolin soil, subjected to thermal loads and a combination of axial and thermal loads (henceforth known as thermo-axial loads). Six tests which included two thermal load tests (35°C and 40°C) and four thermo-axial load tests (100 N and 200 N, combined with 35°C and 40°C thermal loads) were conducted. To simulate the behaviour of geothermal energy piles during its operation, the thermo-axial tests were carried out by applying an axial load to the model pile head, and a subsequent application of thermal load. The model soil was compacted at 90% maximum dry density and had an undrained shear strength of 37 kPa, thus classified as having a firm soil consistency. The behaviour of model pile, having the ultimate load capacity of 460 N, was monitored using a linear variable displacement transducer, load cell and wire thermocouple, to measure the pile head settlement, applied axial load and model pile temperature. The acquired data from this study was used to define the thermo-axial response characteristics of the energy pile model. In this study, the limiting settlement was defined as 10% of the model pile diameter. For thermal load tests, higher thermal loads induced higher values of thermal settlement. At 40°C thermal load an irreversible settlement was observed after the heating and cooling cycle was applied to the model pile. Meanwhile, the pile response to thermo-axial loads were attributed to soil consistency and the magnitude of both the axial and thermal loads applied to the pile. The higher the thermoaxial loads, the higher the settlements occurred. A slight hazard on the model pile was detected, since the settlement

  17. Etude des paramètres de vieillissement d'un système d'isolation film PETP-huile minérale

    NASA Astrophysics Data System (ADS)

    Duart, J. C.; Boisdon, C.; Vuarchex, P.; Ai, Bui

    1994-03-01

    A study of polyethylene terephtalate compatibility with power transformer internal environment is presented. This shall incorporated the ageing methods applicable for the evaluation of materials and a discussion on critical parameters influence. Moisture seems to be the most important factor of PETP degradation. Les auteurs présentent les résultats d'une étude de compatibilité entre le polytéréphtalate d'éthylène (PETP) et l'environnement interne d'un transformateur de puissance. Elle comporte la description des méthodes de vieillissements ainsi qu'une discussion sur l'influence des paramètre, critiques. L'humidité apparaît comme le facteur le plus important de dégradation du PETP.

  18. Potentialités des lasers à fibre dans la génération de rayonnement cohérent UV

    NASA Astrophysics Data System (ADS)

    Martel, G.; Hideur, A.; Ortaç, B.; Lecourt, J.-B.; Chédot, C.; Brunel, M.; Chéron, B.; Limpert, J.; Tunnermann, T.; Grelu, Ph.; Gicquel-Guézo, M.; Labbé, C.; Loualiche, S.; Roussignol, Ph.; Sanchez, F.; Leblond, H.

    2006-12-01

    Le premier laser à fibre dopé aux ions de terres rares fonctionna au tout début des années 60. Il fournissait quelques milliwatts autour de 1 μm. Les décades suivantes virent très peu d'améliorations tant du côté des laboratoires que du point de vue industriel. La dernière décennie (1995/2005) vit se concrétiser la seconde révolution des lasers à fibres. Déjà kilowatt en continu, ils atteignent désormais les 1013 watts/cm2 avec des impulsions de la centaine de femtoseconde. Lors de cette présentation nous passerons en revue les potentialités des lasers à fibre. Nous décrirons les verrous technologiques qui ont été levés ces dix dernières années pour les régimes CW mais aussi femtosecondes. Nous montrerons également comment la prochaine génération de fibres optiques actuellement en développement permettra d'offrir des sources stables et de très haute puissance pour l'avenir proche.

  19. Damage identification of piles based on vibration characteristics.

    PubMed

    Zhang, Xiaozhong; Yao, Wenjuan; Chen, Bo; Liu, Dewen

    2014-01-01

    A method of damage identification of piles was established by using vibration characteristics. The approach focused on the application of the element strain energy and sensitive modals. A damage identification equation of piles was deduced using the structural vibration equation. The equation contained three major factors: change rate of element modal strain energy, damage factor of pile, and sensitivity factor of modal damage. The sensitive modals of damage identification were selected by using sensitivity factor of modal damage firstly. Subsequently, the indexes for early-warning of pile damage were established by applying the change rate of strain energy. Then the technology of computational analysis of wavelet transform was used to damage identification for pile. The identification of small damage of pile was completely achieved, including the location of damage and the extent of damage. In the process of identifying the extent of damage of pile, the equation of damage identification was used in many times. Finally, a stadium project was used as an example to demonstrate the effectiveness of the proposed method of damage identification for piles. The correctness and practicability of the proposed method were verified by comparing the results of damage identification with that of low strain test. The research provided a new way for damage identification of piles. PMID:25506062

  20. Reducing Local Scouring at Bridge Piles Using Collars and Geobags

    PubMed Central

    Akib, Shatirah; Liana Mamat, Noor; Basser, Hossein; Jahangirzadeh, Afshin

    2014-01-01

    The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles. PMID:25247201

  1. Reducing local scouring at bridge piles using collars and geobags.

    PubMed

    Akib, Shatirah; Liana Mamat, Noor; Basser, Hossein; Jahangirzadeh, Afshin

    2014-01-01

    The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles.

  2. Damage Identification of Piles Based on Vibration Characteristics

    PubMed Central

    Zhang, Xiaozhong; Yao, Wenjuan; Chen, Bo; Liu, Dewen

    2014-01-01

    A method of damage identification of piles was established by using vibration characteristics. The approach focused on the application of the element strain energy and sensitive modals. A damage identification equation of piles was deduced using the structural vibration equation. The equation contained three major factors: change rate of element modal strain energy, damage factor of pile, and sensitivity factor of modal damage. The sensitive modals of damage identification were selected by using sensitivity factor of modal damage firstly. Subsequently, the indexes for early-warning of pile damage were established by applying the change rate of strain energy. Then the technology of computational analysis of wavelet transform was used to damage identification for pile. The identification of small damage of pile was completely achieved, including the location of damage and the extent of damage. In the process of identifying the extent of damage of pile, the equation of damage identification was used in many times. Finally, a stadium project was used as an example to demonstrate the effectiveness of the proposed method of damage identification for piles. The correctness and practicability of the proposed method were verified by comparing the results of damage identification with that of low strain test. The research provided a new way for damage identification of piles. PMID:25506062

  3. Reducing local scouring at bridge piles using collars and geobags.

    PubMed

    Akib, Shatirah; Liana Mamat, Noor; Basser, Hossein; Jahangirzadeh, Afshin

    2014-01-01

    The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles. PMID:25247201

  4. A theoretical analysis of the bearing performance of vertically loaded large-diameter pipe pile groups

    NASA Astrophysics Data System (ADS)

    Ding, Xuanming; Zhang, Ting; Li, Ping; Cheng, Ke

    2016-02-01

    This paper aims to present a theoretical method to study the bearing performance of vertically loaded large-diameter pipe pile groups. The interactions between group piles result in different bearing performance of both a single pile and pile groups. Considering the pile group effect and the skin friction from both outer and inner soils, an analytical solution is developed to calculate the settlement and axial force in large-diameter pipe pile groups. The analytical solution was verified by centrifuge and field testing results. An extensive parametric analysis was performed to study the bearing performance of the pipe pile groups. The results reveal that the axial forces in group piles are not the same. The larger the distance from central pile, the larger the axial force. The axial force in the central pile is the smallest, while that in corner piles is the largest. The axial force on the top of the corner piles decreases while that in the central pile increases with increasing of pile spacing and decreasing of pile length. The axial force in side piles varies little with the variations of pile spacing, pile length, and shear modulus of the soil and is approximately equal to the average load shared by one pile. For a pile group, the larger the pile length is, the larger the influence radius is. As a result, the pile group effect is more apparent for a larger pile length. The settlement of pile groups decreases with increasing of the pile number in the group and the shear modulus of the underlying soil.

  5. Prediction des vibrations eoliennes d'un systeme conducteur-amortisseur avec une methode temporelle non lineaire

    NASA Astrophysics Data System (ADS)

    Langlois, Sebastien

    Les vibrations eoliennes sont la cause principale de bris de conducteurs en fatigue des lignes aeriennes de transport d'energie electrique. Ces vibrations sont dues a des detachements tourbillonnaires produits dans le sillage du conducteur. Une methode commune de reduction des vibrations est l'ajout d'amortisseurs de vibrations pres des pinces de suspension. Contrairement aux essais en ligne experimentale, la modelisation numerique permet d'evaluer rapidement et a faible cout la performance d'un amortisseur de vibration sur une portee de ligne aerienne. La technologie la plus frequemment utilisee fait appel au principe de balance d'energie (PBE) en evaluant le niveau de vibrations pour lequel la puissance injectee par le vent est egale a la puissance dissipee par le conducteur et l'amortisseur. Les methodes actuelles pour la prediction des vibrations reposent sur des hypotheses simplificatrices quant a la modelisation de l'interaction conducteur-amortisseur. Une approche prometteuse pour la prediction des vibrations est l'utilisation d'un modele numerique temporel non lineaire qui permet de mieux representer la masse, la geometrie, la rigidite et l'amortissement du systeme. L'objectif principal de ce projet de recherche est de developper un modele numerique avec integration temporelle directe d'un conducteur et d'un amortisseur en vibration permettant de reproduire le comportement dynamique du systeme pour la gamme de frequence et d'amplitude typique des vibrations eoliennes des conducteurs. Un modele par elements finis d'un conducteur seul en vibration resolu par integration temporelle directe a d'abord ete developpe en considerant une rigidite de flexion variable. Comme une rigidite de flexion constante et egale a 50% de la rigidite de flexion maximale theorique ( EImax) est jugee adequate pour la modelisation du conducteur, c'est cette valeur qui a ete utilisee pour la suite du projet. Ensuite, des modeles non-lineaires pour deux types d'amortisseur de

  6. Occupational PAH Exposures during Prescribed Pile Burns

    PubMed Central

    Robinson, M. S.; Anthony, T. R.; Littau, S. R.; Herckes, P.; Nelson, X.; Poplin, G. S.; Burgess, J. L.

    2008-01-01

    Wildland firefighters are exposed to particulate matter and gases containing polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens. Our objective was to evaluate the extent of firefighter exposure to particulate and PAHs during prescribed pile burns of mainly ponderosa pine slash and determine whether these exposures were correlated with changes in urinary 1-hydroxypyrene (1-HP), a PAH metabolite. Personal and area sampling for particulate and PAH exposures were conducted on the White Mountain Apache Tribe reservation, working with 21 Bureau of Indian Affairs/Fort Apache Agency wildland firefighters during the fall of 2006. Urine samples were collected pre- and post-exposure and pulmonary function was measured. Personal PAH exposures were detectable for only 3 of 16 PAHs analyzed: naphthalene, phenanthrene, and fluorene, all of which were identified only in vapor-phase samples. Condensed-phase PAHs were detected in PM2.5 area samples (20 of 21 PAHs analyzed were detected, all but naphthalene) at concentrations below 1 μg m−3. The total PAH/PM2.5 mass fractions were roughly a factor of two higher during smoldering (1.06 ± 0.15) than ignition (0.55 ± 0.04 μg mg−1). There were no significant changes in urinary 1-HP or pulmonary function following exposure to pile burning. In summary, PAH exposures were low in pile burns, and urinary testing for a PAH metabolite failed to show a significant difference between baseline and post-exposure measurements. PMID:18515848

  7. ROCK PILE MOUNTAIN WILDERNESS STUDY AREA, MISSOURI.

    USGS Publications Warehouse

    Pratt, Walden P.; Ellis, Clarence

    1984-01-01

    A geologic and mineral-occurrence survey of the Rock Pile Mountain Wilderness study area in southeastern Missouri indicates the area has little promise for the occurrence of energy and mineral resources. Exploratory drill holes on private land along the west side of the area encountered no mineralization, and none of the rocks or sediments exposed in the area contain any detectable evidence of significant mineralization. Drilling through the Bonneterre Formation, supplemented by geochemical studies of the drill-hole samples, would test the remote possibility of lead mineralization close to the contact with Precambrian rocks.

  8. 6. UPPER NOTTINGHAM TAILING PILE LOOKING DOWN STREAM BED TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. UPPER NOTTINGHAM TAILING PILE LOOKING DOWN STREAM BED TO LOWER NOTTINGHAM. COLLAPSED BUILDINGS, 'B' AND 'C' AND TOP EDGE OF TAILING PILES ARE VISIBLE IN CENTRAL ARE OF PRINT. CAMERA POINTED SOUTHWEST. - Florida Mountain Mining Sites, Upper Nottingham Mine, West face of Florida Mountain, head of Jacobs Gulch, Silver City, Owyhee County, ID

  9. Assessment of timber piles in Clallam County, Washington

    NASA Astrophysics Data System (ADS)

    Pandey, Arun K.; Tyler, Ross; Arnette, Clyde G.; Anthony, Ronald W.

    1998-03-01

    Timber bridges are very common in state and rural highway systems. According to the National Bridge Inventory (NBI), there are 41,743 timber bridges in the United States and another 42,102 bridges with timber decks as a part of the superstructure. As these bridges age, there is a critical need for reliable inspection and assessment methods for evaluating timber members. Under an FHWA mandate, these bridges also need to be evaluated for scour susceptibility. Knowledge of the length of timber piles supporting the bridge is a vital component in calculating scour resistance of a bridge. However, records of timber pile lengths are often nonexistent or incomplete due to the construction practices for timber piles. This paper presents nondestructive evaluation (NDE) techniques used for assessing timber piles on 10 bridges in Clallam County, Washington. Stress wave velocity and resistance drilling techniques were used to determine the presence of and quantify the extent of decay in the piles. A longitudinal stress wave technique was used for determining the length of timber piles. Determination of piles with decay aided in establishing maintenance and repair needs on the bridge substructures. Pile length estimates enabled Clallam County Road Department to determine the scour-susceptibility of these bridges.

  10. Navy-ship plastic waste recycled into marine pilings

    SciTech Connect

    March, F.A.

    1996-02-01

    Seaward International Inc., developed a new, composite, structurally reinforced, plastic-composite marine piling fabricated from 100 percent recycled plastic. A cooperative research program was begun in 1995 between the Navy and Seaward to develop a use for Navy ships waste plastic as a core in the construction of the marine piling.

  11. View south along subtle ridgeline across a pile of removed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View south along subtle ridgeline across a pile of removed gravestones to Doughty-Beck monument, another gravestone pile, and Mill Street houses. - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  12. Packing bunkers and piles to maximize forage preservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage is a valuable commodity stored on dairy farms. Bunker and pile silos have increased in use due to increasing herd size. Losses in feed value in bunker and pile silos are frequently higher than they should be because producers are not packing them sufficiently to exclude oxygen during the stor...

  13. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  14. Traitement par plasma thermique d'une liqueur caustique pour la destruction des cyanures

    NASA Astrophysics Data System (ADS)

    Fortin, Luc

    L'objectif principal de cette recherche est d'evaluer la possibilite de traiter le lixiviat de brasques usees produit par le procede LCL&L (Lixiviation a bas caustique et chaulage) par contact direct avec un jet de plasma thermique. L'utilisation d'un chalumeau au plasma permet d'eliminer les problemes de reaction avec les produits de combustion relies a l'utilisation de chalumeaux conventionnels (e.g. carbonatation du NaOH en Na2CO3). Le fait de se servir de ce type de chalumeau en mode submerge pour le traitement d'une solution liquide constitue l'originalite du projet. Les essais effectues dans le cadre de ce travail experimental sont realises a l'echelle banc d'essai dans un premier temps. Ils visent a determiner le taux de decomposition des cyanures contenus dans le lixiviat sous des conditions de plasma thermique en fonction de differents parametres et a faire la mise a l'echelle d'un reacteur pilote. La puissance electrique fournie au chalumeau, la temperature et la pression d'operation, le point d'addition d'eau, le volume de lixiviat traite et l'addition de peroxyde d'hydrogene (H2O2) comme co-reactif ont tous un impact sur le taux de destruction des cyanures trouve. Sous toutes les conditions etudiees, le reacteur plasma offre un taux de destruction plus rapide qu'un reacteur agite sous pression pour une meme concentration en cyanures. Ainsi, la comparaison de la constante cinetique obtenue pour le reacteur agite avec une constante similaire pour le reacteur plasma (pente du graphique -ln(C/C0) en fonction du temps) est de 0.04x10-3 s-1 vs 0.59x10-3 s-1 a 100°C et de 1.85x10-3 s-1' vs 3x10 -3 s-1s a 170°C. Ces resultats confirment que le plasma joue un role important sur la decomposition des cyanures et qu'il contribue a en augmenter le taux de destruction. Suite aux connaissances acquises sur le banc d'essai, un reacteur pilote est concu. Un chalumeau au plasma d'une puissance de 60 kW-150 kW et fonctionnant avec l'air comme gaz plasmagene y est

  15. Method of extracting coal from a coal refuse pile

    DOEpatents

    Yavorsky, Paul M.

    1991-01-01

    A method of extracting coal from a coal refuse pile comprises soaking the coal refuse pile with an aqueous alkali solution and distributing an oxygen-containing gas throughout the coal refuse pile for a time period sufficient to effect oxidation of coal contained in the coal refuse pile. The method further comprises leaching the coal refuse pile with an aqueous alkali solution to solubilize and extract the oxidized coal as alkali salts of humic acids and collecting the resulting solution containing the alkali salts of humic acids. Calcium hydroxide may be added to the solution of alkali salts of humic acid to form precipitated humates useable as a low-ash, low-sulfur solid fuel.

  16. Centrifuge Modeling of Piles Subjected to Lateral Loads

    NASA Astrophysics Data System (ADS)

    Brant, Logan; Ling, Hoe I.

    There are many applications where piles are employed to absorb and deflect lateral impact loads. Structural elements of this type are used to protect infrastructure and are commonly found at marine sites. A series of model tests have been conducted using Columbia University's centrifuge facility to better understand the performance of piles subjected to these loading conditions. A device was designed to install and laterally load single model piles during centrifuge flight. This device uniquely contains two lateral loading systems, one which allows static testing and another appropriate for dynamic tests. This research examines the behavior of tubular steel piles embedded within dry or saturated soil and subjected to varied rates of lateral loading. This investigation provides insight on the contribution of lateral loading rates to the behavior of piles.

  17. Distributed fibre optic strain measurements on a driven pile

    NASA Astrophysics Data System (ADS)

    Woschitz, Helmut; Monsberger, Christoph; Hayden, Martin

    2016-05-01

    In civil engineering pile systems are used in unstable areas as a foundation of buildings or other structures. Among other parameters, the load capacity of the piles depends on their length. A better understanding of the mechanism of load-transfer to the soil would allow selective optimisation of the system. Thereby, the strain variations along the loaded pile are of major interest. In this paper, we report about a field trial using an optical backscatter reflectometer for distributed fibre-optic strain measurements along a driven pile. The most significant results gathered in a field trial with artificial pile loadings are presented. Calibration results show the performance of the fibre-optic system with variations in the strain-optic coefficient.

  18. Optimal Design of Sheet Pile Wall Embedded in Clay

    NASA Astrophysics Data System (ADS)

    Das, Manas Ranjan; Das, Sarat Kumar

    2015-09-01

    Sheet pile wall is a type of flexible earth retaining structure used in waterfront offshore structures, river protection work and temporary supports in foundations and excavations. Economy is an essential part of a good engineering design and needs to be considered explicitly in obtaining an optimum section. By considering appropriate embedment depth and sheet pile section it may be possible to achieve better economy. This paper describes optimum design of both cantilever and anchored sheet pile wall penetrating clay using a simple optimization tool Microsoft Excel ® Solver. The detail methodology and its application with examples are presented for cantilever and anchored sheet piles. The effects of soil properties, depth of penetration and variation of ground water table on the optimum design are also discussed. Such a study will help professional while designing the sheet pile wall penetrating clay.

  19. Small asteroids - rubble piles or boulders?

    NASA Astrophysics Data System (ADS)

    Harris, Alan W.

    2013-10-01

    The asteroid rotation spin barrier at ~2.2 h period among asteroids 10 km > D > 200 m doesn’t prove all such asteroids are rubble piles, and the faster rotations among smaller asteroids doesn’t require monolithic strength, either. Only a very modest strength, perhaps no more than van der Waals force, might suffice to hold regolith together on a small super-fast rotator (Sanchez & Scheeres, 2013, arXif:1306.1622v1). The problem is that for a constant or only slowly varying strength with respect to diameter, the spin barrier becomes proportional to 1/D below the size where material strength is dominant, or perhaps a bit steeper if strength increases with decreasing D. What we observe in the distribution of asteroid spins versus diameter is that below D ~ 200 m, the spin barrier goes up at least ~D-3.5, if not abruptly. Models with constant or slowly varying strength fail to fit this observation, and the abrupt transition cannot be an observational selection effect: the void in the phase space of rotations would be among the easiest rotations to observe, e.g. the one conspicuous exception, 2001 OE84 (D ~ 0.7 km, P = 0.5 h) was easily and unambiguously measured (Pravec, et al. 2002, Proc. ACM 2002, ESA SP-500, 743-745). This abrupt transition is most easily explained as a real transition in material properties of asteroids in the size range ~200 m diameter, from “rubble pile” to “boulder”, although neither term may be fully descriptive of the actual structure. Two other lines of evidence suggest that this transition in properties is real: the dip in the size-frequency distribution of NEAs is maximum at ~150 m, suggesting that a transition to stronger material structure occurs about there, and we observe, e.g., Tunguska and the recent Chelyabinsk bolide, that bodies in the tens of meters size range entering the atmosphere behave more like solid rocks than rock piles (Boslough & Crawford 2008, Int. J. Imp. Eng. 35, 1441-1448). I encourage those doing computer

  20. Threat from Rubble-Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Schultz, P. H.

    2015-12-01

    While chondrites are the most common meteoroids to enter our atmosphere, they represent a small fraction of recovered falls. Most stony meteorites disrupt during entry, consumed by ablation or lost by weathering; in contrast, small iron meteorites (<10 m) disrupt and disperse to create strewnfields due to interacting atmospheric bow shocks [e.g., Passey and Melosh, 1980]. The Carancas impact crater in 2007, however, challenged our understanding [Tancredi et al., 2008]: (a) first eyewitness of a crater formed by a stony meteorite; (b) undetected thermal entry at altitude; (c) no accessory meteorite falls; (d) "explosion" (not low-speed compression) crater; (e) infrasound/seismic data indicating a high-speed entry/collision; and (f) petrologic evidence for shock deformation/melting in breccias indicative of speeds >4 km/s. Although a monolithic chondrite (~ 10 m across) might allow surviving entry, most objects of this size contain multiple flaws, ensuring atmospheric disruption. Hence, an alternative "needle model" was proposed wherein a small rubble-pile object gradually re-shaped itself during entry [Schultz, 2008], a process that minimizes drag, thermal signatures of entry, and catastrophic disruption. First proposed to account for smaller than expected craters on Venus [Schultz, 1992], such a process resembles subsequent Shoemaker-Levy entry models [Boslough and Crawford, 1997] that predicted much deeper entry than standard models. Laboratory experiments at the NASA Ames Vertical Gun Range simulated this process by breaking-up hypervelocity projectiles into a cloud of debris and tracking its path at near-full atmospheric pressure. The resulting cloud of fragments exhibited less deceleration than a solid sphere at the same speed. Moreover, shadowgraphs revealed constituent fragments "surfing" the pressure jump within the mach cone/column. Previous models proposed that crater-forming impacts must be >50-100 m in diameter in order to survive entry [Bland and

  1. Formation et Evolution des Quasars et Contraintes cosmologiques

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, Evanthia

    2000-06-01

    èle d'accrétion autour d'un trou noir massif a alors été implementé dans le code d'évolution des galaxies. Ce modèle sera opérationnel au début de l'automne et fera des prédictions sur l'évolution de la fonction de luminosité des quasars, leur connexion aux galaxies Seyfert et aux starbursts, leur durée de vie et leur pourcentage dans les différent types de galaxies. Le grand intérêt du modèle sera la sortie, en même temps, d'une fonction de luminosité pour les quasars et de l'histoire du taux de formation stellaire, deux phénomènes qui pourront être étudiés simultanément. Par ailleurs, j'ai développé un modèle analytique basé sur les instabilités des disques d'accrétion, en collaboration avec A. Siemiginowska et M. Elvis du CfA, Cambridge, USA, donnant des résultats satisfaisants sur la fonction de luminosité des quasars à grand redshift. L'hypothèse d'une relation linéaire entre les masses du trou noir central et du halo de matière noire qui l'héberge a été rejetée. Le même modèle impose des contraintes sur la valeur de l'exposant du spectre de puissance primordial, P(k), qui décrit les fluctuations primordiales.

  2. Analysis of Wave Fields induced by Offshore Pile Driving

    NASA Astrophysics Data System (ADS)

    Ruhnau, M.; Heitmann, K.; Lippert, T.; Lippert, S.; von Estorff, O.

    2015-12-01

    Impact pile driving is the common technique to install foundations for offshore wind turbines. With each hammer strike the steel pile - often exceeding 6 m in diameter and 80 m in length - radiates energy into the surrounding water and soil, until reaching its targeted penetration depth. Several European authorities introduced limitations regarding hydroacoustic emissions during the construction process to protect marine wildlife. Satisfying these regulations made the development and application of sound mitigation systems (e.g. bubble curtains or insulation screens) inevitable, which are commonly installed within the water column surrounding the pile or even the complete construction site. Last years' advances have led to a point, where the seismic energy tunneling the sound mitigation systems through the soil and radiating back towards the water column gains importance, as it confines the maximum achievable sound mitigation. From an engineering point of view, the challenge of deciding on an effective noise mitigation layout arises, which especially requires a good understanding of the soil-dependent wave field. From a geophysical point of view, the pile acts like a very unique line source, generating a characteristic wave field dominated by inclined wave fronts, diving as well as head waves. Monitoring the seismic arrivals while the pile penetration steadily increases enables to perform quasi-vertical seismic profiling. This work is based on datasets that have been collected within the frame of three comprehensive offshore measurement campaigns during pile driving and demonstrates the potential of seismic arrivals induced by pile driving for further soil characterization.

  3. Unsaturated flow modeling of a retorted oil shale pile.

    SciTech Connect

    Bond, F.W.; Freshley, M.D.; Gee, G.W.

    1982-10-01

    The objective of this study was to demonstrate the capabilities of the UNSAT1D model for assessing this potential threat to the environment by understanding water movement through spent shale piles. Infiltration, redistribution, and drainage of water in a spent shale pile were simulated with the UNSAT1D model for two test cases: (1) an existing 35 m pile; and (2) a transient pile growing at a rate of 10 m/year for 5 years. The first test case simulated three different layering scenarios with each one being run for 1 year. The second test case simulated two different initial moisture contents in the pile with each simulation being run for 30 years. Grand Junction and Rifle, Colorado climatological data were used to provide precipitation and potential evapotranspiration for a wet (1979) and dry (1976) year, respectively. Hydraulic properties obtained from the literature on Paraho process spent shale soil, and clay were used as model input parameters to describe water retention and hydraulic conductivity characteristics. Plant water uptake was not simulated in either test case. The two test cases only consider the evaporation component of evapotranspiration, thereby maximizing the amount of water infiltrating into the pile. The results of the two test cases demonstrated that the UNSAT1D model can adequately simulate flow in a spent shale pile for a variety of initial and boundary conditions, hydraulic properties, and pile configurations. The test cases provided a preliminary sensitivity analysis in which it was shown that the material hydraulic properties, material layering, and initial moisture content are the principal parameters influencing drainage from the base of a pile. 34 figures, 4 tables.

  4. Pile mixing increases greenhouse gas emissions during composting of dairy manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of pile mixing on greenhouse gas (GHG) emissions from stored dairy manure was determined using large flux chambers designed to completely cover pilot-scale manure piles. GHG emissions from piles that were mixed four times during the 80 day trial were about 20% higher than unmixed piles. ...

  5. Piled tool will level subsea well template for Heidrun TLP

    SciTech Connect

    Not Available

    1992-01-13

    This paper reports on piled leveling tools that were contracted for use during the installation of the subsea well template for Conoco Norway Inc.'s Heidrun tension leg platform (TLP) in the Norwegian sector of the North Sea. The leveling tools are employed after a template has been positioned on the seafloor and anchor pilings have been driven through the template sleeves. One or more tools are lowered and landed on anchor pilings at the low side of the template. No diver support or guidelines are required.

  6. Filtrage actif des harmoniques en courant et en tension des reseaux électriques : modélisation, simulation numérique et expérimentation

    NASA Astrophysics Data System (ADS)

    Lott, C.; Lapierre, O.; Pouliquen, H.; Saadate, S.

    1997-12-01

    Static converters generate harmonic currents and consume reactive power. These new phenomena on the mains generate some perturbations going from malfunction to destruction of the connected sensible equipments. In this paper disturbances generated by static converters are studied. Some solutions based on passive and active filtering are presented. Some passive filter design elements are given. Active filter is then studied. Both structures, current and voltage, are studied and voltage source structure is chosen. Different active filter control principles are presented. The active and reactive instantaneous power theory give good results for harmonic identification. Some numerical simulation are realized. A 100kVA prototype is realized and tested on an industrial site. The GTO prototype shows good results for harmonic filtering. The voltage active filtering is also presented. The active filter eliminates voltage harmonics on 400 V busbar generated by a MVA SCR bridge connected on 15kV busbar. Les convertisseurs statiques absorbent des courants non sinusoïdidaux et consomment généralement de la puissance réactive. Ces deux phénomènes nouveaux sur le réseau ont engendré un certain nombre de perturbations allant du dysfonctionnement d'un équipement jusqu'à la destruction d'une partie des équipements connectés. Dans cet article, les problèmes liés aux perturbations générées par les convertisseurs statiques ont été étudiés et des solutions visant à les éliminer ont été présentées. Elles portent sur les méthodes de filtrage passif et actif. Quelques éléments de définition et de dimensionnement de filtres passifs sont donnés. Le filtrage actif est ensuite traité. Les deux structures, courant et tension, sont étudiées et la structure tension a été retenue pour la suite de l'article. Différents principes de contrôle du filtre actif à structure tension ont été présentés. La méthode d'identification des harmoniques par le principe du

  7. As Traffic Piles Up, So Does Air Pollution

    MedlinePlus

    ... 160914.html As Traffic Piles Up, So Does Air Pollution To minimize exposure, researchers recommend shutting windows and ... Doing so can reduce your exposure to toxic air pollution from a traffic jam by up to 76 ...

  8. Airborne thermography of temperature patterns in sugar beet piles

    NASA Technical Reports Server (NTRS)

    Moore, D. G.; Bichsel, S.

    1975-01-01

    An investigation was conducted to evaluate the use of thermography for locating spoilage areas (chimneys) within storage piles and to subsequently use the information for the scheduling of their processing. Thermal-infrared quantitative scanner data were acquired initially on January 16, 1975, over the storage piles at Moorhead, Minnesota, both during the day and predawn. Photographic data were acquired during the day mission to evaluate the effect of uneven snow cover on the thermal emittance, and the predawn thermography was used to locate potential chimneys. The piles were examined the day prior for indications of spoilage areas, and the ground crew indicated that no spoilage areas were located using their existing methods. Nine spoilage areas were interpreted from the thermography. The piles were rechecked by ground methods three days following the flights. Six of the nine areas delineated by thermography were actual spoilage areas.

  9. Biodeterioration of concrete piling in the Arabian Gulf

    SciTech Connect

    Jadkowski, T.K.; Wiltsie, E.A.

    1985-03-01

    Concrete is one of the most widely used materials in marine construction because of its characteristic durability in sea environments. Recent inspection of concrete piles installed in the Arabian Gulf has revealed that concrete with high content of calcareous aggregate is susceptible to biodeterioration. Marine rock borers and sponges, which are common in areas where the seabed is composed of limestone rock, have been identified as the marine species responsible for the biodeterioration. Boring organisms pose a significant threat to concrete pile structural integrity. Boreholes deteriorate concrete and expose outer pile reinforcement to seawater. This paper describes the causes and magnitude of biodeterioration of piles installed in the Arabian Gulf and presents design parameters and material specifications for the selected preventive repair system.

  10. 4. West side of pier showing distinct piling configuration. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. West side of pier showing distinct piling configuration. - Charlestown Navy Yard, Pier 10, Between Piers 9 & 11 along Mystic River on Charlestown Waterfront at eastern edge of Charlestown Navy Yard, Boston, Suffolk County, MA

  11. 2. Pilings at end of Pier 11, low tide, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Pilings at end of Pier 11, low tide, view to north. - Charlestown Navy Yard, Pier 11, Charlestown Waterfront at confluence of Little Mystic Channel & Mystic River at northernmost ent of Navy Yard, Boston, Suffolk County, MA

  12. 12. Underneath view of pilings and chain supports on sw ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Underneath view of pilings and chain supports on sw side near midsection; looking SE at low tide. - Pacific Creosoting Plant, West Dock, 5350 Creosote Place, Northeast, Bremerton, Kitsap County, WA

  13. 21. View looking W from Brooklyn shore with pier pilings ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. View looking W from Brooklyn shore with pier pilings in left foreground. Jet Lowe, photographer, 1982. - Brooklyn Bridge, Spanning East River between Park Row, Manhattan and Sands Street, Brooklyn, New York County, NY

  14. VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK TOP, WITH VERTICAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK TOP, WITH VERTICAL ELEMENTS IN BACKGROUND, LEVEL 0’, LOOKING NORTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  15. 69. VIEW OF DECK AND PILINGS FROM LIFEGUARD TOWER AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    69. VIEW OF DECK AND PILINGS FROM LIFEGUARD TOWER AT 2ND TEE, LOOKING NORTH, SHOWING NEPTUNE'S LOCKER AND CAPTAIN'S GALLEY IN BACKGROUND AT RIGHT - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  16. 1. GENERAL VIEW OF ENGINE PILE OF AGGREGATE AND MEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF ENGINE PILE OF AGGREGATE AND MEN WAITING WITH WHEELBARROWS FILLED WITH AGGREGATE. TAKE DEC. 7, 1927. - Marsh Rainbow Arch Bridge, West Eighth Street North, Newton, Jasper County, IA

  17. 8. Roaring Fork Motor Nature Trail, handbuilt rock pile. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Roaring Fork Motor Nature Trail, hand-built rock pile. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  18. VIEW OF SOUTHERN QUARRY, FACING SOUTH, WITH ROCK PILES IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF SOUTHERN QUARRY, FACING SOUTH, WITH ROCK PILES IN FOREGROUND - Granite Hill Plantation, Quarry No. 2, South side of State Route 16, 1.3 miles northeast east of Sparta, Sparta, Hancock County, GA

  19. 48. EXCAVATING AND DRIVING PILES FOR SHOOFLY BRIDGE, YOLO COUNTY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. EXCAVATING AND DRIVING PILES FOR SHOOFLY BRIDGE, YOLO COUNTY SIDE OF RIVER, November 7, 1934 - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  20. 10. Substructure of bridge, showing timber bents, piles, crossbracing, caps ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Substructure of bridge, showing timber bents, piles, cross-bracing, caps and stringers under deck. View to northeast. - Outlet Creek Bridge, Sullivan Lake Ranger Administrative Site, Metaline Falls, Pend Oreille County, WA

  1. Processing Satellite Imagery To Detect Waste Tire Piles

    NASA Technical Reports Server (NTRS)

    Skiles, Joseph; Schmidt, Cynthia; Wuinlan, Becky; Huybrechts, Catherine

    2007-01-01

    A methodology for processing commercially available satellite spectral imagery has been developed to enable identification and mapping of waste tire piles in California. The California Integrated Waste Management Board initiated the project and provided funding for the method s development. The methodology includes the use of a combination of previously commercially available image-processing and georeferencing software used to develop a model that specifically distinguishes between tire piles and other objects. The methodology reduces the time that must be spent to initially survey a region for tire sites, thereby increasing inspectors and managers time available for remediation of the sites. Remediation is needed because millions of used tires are discarded every year, waste tire piles pose fire hazards, and mosquitoes often breed in water trapped in tires. It should be possible to adapt the methodology to regions outside California by modifying some of the algorithms implemented in the software to account for geographic differences in spectral characteristics associated with terrain and climate. The task of identifying tire piles in satellite imagery is uniquely challenging because of their low reflectance levels: Tires tend to be spectrally confused with shadows and deep water, both of which reflect little light to satellite-borne imaging systems. In this methodology, the challenge is met, in part, by use of software that implements the Tire Identification from Reflectance (TIRe) model. The development of the TIRe model included incorporation of lessons learned in previous research on the detection and mapping of tire piles by use of manual/ visual and/or computational analysis of aerial and satellite imagery. The TIRe model is a computational model for identifying tire piles and discriminating between tire piles and other objects. The input to the TIRe model is the georeferenced but otherwise raw satellite spectral images of a geographic region to be surveyed

  2. Pile Structure Program, Projected Start Date : January 1, 2010 (Implementation).

    SciTech Connect

    Collins, Chris; Corbett, Catherine; Ebberts, Blaine

    2009-07-27

    The 2008 Federal Columbia River Power System Biological Opinion includes Reasonable and Prudent Alternative 38-Piling and Piling Dike Removal Program. This RPA directs the Action Agencies to work with the Estuary Partnership to develop and implement a piling and pile dike removal program. The program has since evolved to include modifying pile structures to enhance their habitat value and complexity by adding large woody debris. The geographic extent of the Pile Structure Program (PSP) includes all tidally-influenced portions of the lower Columbia River below Bonneville Dam; however, it will focus on the mainstem. The overarching goal of the PSP is to enhance and restore ecosystem structure and function for the recovery of federally listed salmonids through the active management of pile structures. To attain this goal, the program team developed the following objectives: (1) Develop a plan to remove or modify pile structures that have lower value to navigation channel maintenance, and in which removal or modification will present low-risk to adjacent land use, is cost-effective, and would result in increased ecosystem function. (2) Determine program benefits for juvenile salmonids and the ecosystem through a series of intensively monitored pilot projects. (3) Incorporate best available science and pilot project results into an adaptive management framework that will guide future management by prioritizing projects with the highest benefits. The PSP's hypotheses, which form the basis of the pilot project experiments, are organized into five categories: Sediment and Habitat-forming Processes, Habitat Conditions and Food Web, Piscivorous Fish, Piscivorous Birds, and Toxic Contaminant Reduction. These hypotheses are based on the effects listed in the Estuary Module (NOAA Fisheries in press) and others that emerged during literature reviews, discussions with scientists, and field visits. Using pilot project findings, future implementation will be adaptively managed to

  3. The equivalence between dislocation pile-ups and cracks

    NASA Technical Reports Server (NTRS)

    Liu, H. W.; Gao, Q.

    1990-01-01

    Cracks and dislocation pile-ups are equivalent to each other. In this paper, the physical equivalence between cracks and pile-ups is delineated, and the relationshps between crack-extension force, force on the leading dislocation, stress-intensity factor, and dislocation density are reviewed and summarized. These relations make it possible to extend quantitatively the recent advances in the concepts and practices of fracture mechanics to the studies of microfractures and microplastic deformations.

  4. Slime thickness evaluation of bored piles by electrical resistivity probe

    NASA Astrophysics Data System (ADS)

    Chun, Ok-Hyun; Yoon, Hyung-Koo; Park, Min-Chul; Lee, Jong-Sub

    2014-09-01

    The bottoms of bored piles are generally stacked with soil particles, both while boreholes are being drilled, and afterward. The stacked soils are called slime, and when loads are applied on the pile, increase the pile settlement. Thus to guarantee the end bearing capacity of bored piles, the slime thickness should be precisely detected. The objective of this study is to suggest a new method for evaluating the slime thickness, using temperature compensated electrical resistivity. Laboratory studies are performed in advance, to estimate and compare the resolution of the electrical resistivity probe (ERP) and time domain reflectometry (TDR). The electrical properties of the ERP and TDR are measured using coaxial type electrodes and parallel type two-wire electrodes, respectively. Penetration tests, conducted in the fully saturated sand-clay mixtures, demonstrate that the ERP produces a better resolution of layer detection than TDR. Thus, field application tests using the ERP with a diameter of 35.7 mm are conducted for the investigation of slime thickness in large diameter bored piles. Field tests show that the slime layers are clearly identified by the ERP: the electrical resistivity dramatically increases at the interface between the slurry and slime layer. The electrical resistivity in the slurry layer inversely correlates with the amount of circulated water. This study suggests that the new electrical resistivity method may be a useful method for the investigation of the slime thickness in bored piles.

  5. Conoco installs eight-pile rig on four-pile platform

    SciTech Connect

    Albaugh, E.K.

    1983-11-01

    Rig 122 recently became the largest standard self-contained drilling rig ever to be mounted on a four-pile, tender-style platform. The conversion sacrificed none of the rig's deep drilling capability, and enabled Conoco to utilize a self-contained platform drilling rig on a satellite platform in the same field. Two cantilever beams, extending some 42 ft beyond platform columns on two sides, support rig weight. Modifications to the rig include separation of pump and engine packages, a pipe-rack extension and a novel skidding system.

  6. Preliminary report on coal pile, coal pile runoff basins, and ash basins at the Savannah River Site: effects on groundwater

    SciTech Connect

    Palmer, E.

    1997-04-28

    Coal storage piles, their associated coal pile runoff basins and ash basins could potentially have adverse environmental impacts, especially on groundwater. This report presents and summarizes SRS groundwater and soil data that have been compiled. Also, a result of research conducted on the subject topics, discussions from noted experts in the field are cited. Recommendations are made for additional monitor wells to be installed and site assessments to be conducted.

  7. The Supercritical Pile Model for GRBs

    NASA Technical Reports Server (NTRS)

    Kazanas, D.

    2005-01-01

    We present the spectral and temporal radiative signatures expected within the "Supercritical Pile" model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined scheme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same time it leads to spectra which exhibit a peak in the burst nuF(sub nu) distribution at an energy E(sub p) approx. equal to 1 MeV in the observer s frame, in agreement with observation and largely independent of the Lorentz factor r of the associated relativistic outflow. Futhermore, this scheme does not require (but does not preclude) acceleration of particles at the shock other than that provided by the isotropization of the flow bulk kinetic energy on the RBW frame. In the present paper we model in detail the evolution of protons, electrons and photons from a RBW to produce detailed spectra of the prompt GRB phase as a function of time from across a very broad range spanning roughly 4 log10Gamma decades in frequency. The model spectra are in general agreement with observations and provide a means for the delineating of the model parameters through direct comparison with trends observed in GRB properties.

  8. The Supercritical Pile Model for GRBs

    NASA Technical Reports Server (NTRS)

    Kazanas, Demos

    2006-01-01

    We present the spectral and temporal radiative signatures expected within the Supercritical Pile model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined scheme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same time it leads to spectra which exhibit a peak in the burst nuF(sub nu) distribution at an energy E(sub p) approximately equal to 1 MeV in the observer s frame, in agreement with observation and largely independent of the Lorentz factor GAMMA of the associated relativistic outflow. Furthermore, this scheme does not require (but does not preclude) acceleration of particles at the shock other than that provided by the isotropization of the flow bulk kinetic energy on the RBW frame. In the present paper we model in detail the evolution of protons, electrons and photons from a RBW to produce detailed spectra of the prompt GRB phase as a function of time from across a very broad range spanning roughly 4 log10 GAMMA decades in frequency. The model spectra are in general agreement with observations and provide a means for the delineating of the model parameters through direct comparison with trends observed in GRB properties.

  9. The Supercritical Pile Model for GRBs

    NASA Technical Reports Server (NTRS)

    Kazanas, Demos

    2005-01-01

    We present the spectral and tempora1 radiative signatures expected within the "Supercritical Pile" model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined theme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same it leads to spectra which exhibit a peak in the burst vFv, distribution at an energy Ep l. MeV in the observer's frame, in agreement with observation and largely independent of the Lorentz factor P of the associated relativistic outflow. Furthermore, this scheme does not require (but does not preclude) acceleration of particles at the shock other than that provided by the isotropization of the flow kinetic energy on the RBW frame. In the present paper we model in detail the evolution of protons, electrons and photons from a RBW within the framework of this model to produce detailed spectra of the prompt GRB phase as a function of time from across a very broad range spanning roughly 4log10P decades in frequency. The model spectra are in general agreement with observations and provide a means for the delineating of the model parameters through direct comparison with trends observed in GRB properties.

  10. The Supercritical Pile Model for GRBs

    NASA Astrophysics Data System (ADS)

    Mastichiadis; Kazanas

    2006-02-01

    We present the spectral and temporal radiative signatures expected withinthe quot;Supercritical Pile\\" model of Gamma Ray Bursts (GRB). This modelis motivated by the need for a process that provides the dissipationnecessary in GRB and presents a well defined scheme for converting theenergy stored in the relativistic protons of theRelativistic Blast Waves (RBW) associated with GRB into radiation; at thesame time it leads to spectra which exhibit a peak in the burst nuF_{nu} distribution at an energy E_p simeq 1 MeV in theobserverapos;s frame, in agreement with observation and largelyindependent of the Lorentz factor Gamma of the associated relativisticoutflow. Futhermore, this scheme does not require (but does notpreclude) acceleration of particles at the shock other than that providedby the isotropization of the flow bulk kinetic energy on the RBW frame. Inthe present paper we model in detail the evolution of protons, electronsand photons from a RBW within the framework of this model to producedetailed spectra of the prompt GRB phase as a function of time from acrossa very broad range spanning roughly 4 log_{10} Gamma decades$ in frequency. The model spectra are in generalagreement with observations and provide a means for the delineating of themodel parameters through direct comparison with trends observed in GRBproperties.

  11. Parametric study on the effects of pile inclination angle on the response of batter piles in offshore jacket platforms

    NASA Astrophysics Data System (ADS)

    Aminfar, Ali; Ahmadi, Hamid; Aminfar, Mohammad Hossein

    2016-06-01

    Offshore jacket-type platforms are attached to the seabed by long batter piles. In this paper, results from a finite element analysis, verified against experimental data, are used to study the effect of the pile's inclination angle, and its interaction with the geometrical properties of the pile and the geotechnical characteristics of the surrounding soil on the behavior of the inclined piles supporting the jacket platforms. Results show that the inclination angle is one of the main parameters affecting the behavior of an offshore pile. We investigated the effect of the inclination angle on the maximum von Mises stress, maximum von Mises elastic strain, maximum displacement vector sum, maximum displacement in the horizontal direction, and maximum displacement in the vertical direction. The pile seems to have an operationally optimal degree of inclination of approximately 5°. By exceeding this value, the instability in the surrounding soil under applied loads grows extensively in all the geotechnical properties considered. Cohesive soils tend to display poorer results compared to grained soils.

  12. Dynamic load testing on the bearing capacity of prestressed tubular concrete piles in soft ground

    NASA Astrophysics Data System (ADS)

    Yu, Chuang; Liu, Songyu

    2008-11-01

    Dynamic load testing (DLT) is a high strain test method for assessing pile performance. The shaft capacity of a driven PTC (prestressed tubular concrete) pile in marine soft ground will vary with time after installation. The DLT method has been successfully transferred to the testing of prestressed pipe piles in marine soft clay of Lianyungang area in China. DLT is investigated to determine the ultimate bearing capacity of single pile at different period after pile installation. The ultimate bearing capacity of single pile was founded to increase more than 70% during the inventing 3 months, which demonstrate the time effect of rigid pile bearing capacity in marine soft ground. Furthermore, the skin friction and axial force along the pile shaft are presented as well, which present the load transfer mechanism of pipe pile in soft clay. It shows the economy and efficiency of DLT method compared to static load testing method.

  13. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    PubMed

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems. PMID:26949962

  14. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting

    PubMed Central

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-01-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems. PMID:26949962

  15. Numerical experiments with rubble piles: equilibrium shapes and spins

    NASA Astrophysics Data System (ADS)

    Richardson, Derek C.; Elankumaran, Pradeep; Sanderson, Robyn E.

    2005-02-01

    We present numerical experiments investigating the shape and spin limits of self-gravitating "perfect" rubble piles that consist of identical, smooth, rigid, spherical particles with configurable normal coefficient of restitution and no sliding friction. Such constructs are currently employed in a variety of investigations, ranging from the formation of asteroid satellites to the dynamical properties of Saturn's densest rings. We find that, owing to cannonball stacking behavior, rubble piles can maintain non-spherical shapes without bulk spin, unlike a fluid, and can spin faster than a perfect fluid before shedding mass, consistent with the theory for the more general continuum rubble pile model (Holsapple, 2004, Icarus 172, 272-303). Rubble piles that reassemble following a catastrophic disruption reconfigure themselves to lie within stability limits predicted by the continuum theory. We also find that coarse configurations consisting of a small number of particles are more resistant to tidal disruption than fine configurations with many particles. Overall this study shows that idealized rubble piles behave qualitatively in a manner similar to certain granular materials, at least in the limit where global shape readjustments and/or mass shedding begins. The limits obtained here may provide constraints on the possible internal structure of some small Solar System bodies that have extreme shapes or are under high stress. Amalthea is presented as a case study.

  16. Design of Jetty Piles Using Artificial Neural Networks

    PubMed Central

    2014-01-01

    To overcome the complication of jetty pile design process, artificial neural networks (ANN) are adopted. To generate the training samples for training ANN, finite element (FE) analysis was performed 50 times for 50 different design cases. The trained ANN was verified with another FE analysis case and then used as a structural analyzer. The multilayer neural network (MBPNN) with two hidden layers was used for ANN. The framework of MBPNN was defined as the input with the lateral forces on the jetty structure and the type of piles and the output with the stress ratio of the piles. The results from the MBPNN agree well with those from FE analysis. Particularly for more complex modes with hundreds of different design cases, the MBPNN would possibly substitute parametric studies with FE analysis saving design time and cost. PMID:25177724

  17. A simple approach for calculating pile skin friction in clays

    SciTech Connect

    Mirza, U.A.A.

    1995-12-31

    A simple method is presented for calculating static shaft resistance of a pile driven into clay. The method is based on correlations established for North Sea clays between index properties and strengths. Application of the method to half a dozen full scale pile load tests which are part of the API RP2A`s data base and include a wide range of plasticity properties, overconsolidation ratios and strengths, is described. Except for short piles in very stiff to hard clays, the predictions agree very well with the measurements. The correlations presented allows an assessment of residual skin friction and indicate the importance of the liquidity index of the clay in static capacity calculations.

  18. Identification of Defects in Piles Through Dynamic Testing

    NASA Astrophysics Data System (ADS)

    Liao, Shutao T.; Roesset, Jose M.

    1997-04-01

    The objective of this work was to evaluate the theoretical capabilities of the non-destructive impact-response method in detecting the existence of a single defect in a pile, its location and its length. The cross-section of the pile is assumed to be circular and the defects are assumed to be axisymmetric in geometry. As mentioned in the companion paper, special codes utilizing one-dimensional (1-D) and three-dimensional (3-D) axisymmetric finite element models were developed to simulate the responses of defective piles to an impact load. Extensive parametric studies were then performed. In each study, the results from the direct use of time histories of displacements or velocities and the mechanical admittance (or mobility) function were compared in order to assess their capabilities. The effects of the length and the width of a defect were also investigated using these methods. Int. J. Numer. Anal. Meth. Geomech., vol. 21, 277-291 (1997)

  19. Cumulative Damage in Strength-Dominated Collisions of Rocky Asteroids: Rubble Piles and Brick Piles

    NASA Technical Reports Server (NTRS)

    Housen, Kevin

    2009-01-01

    Laboratory impact experiments were performed to investigate the conditions that produce large-scale damage in rock targets. Aluminum cylinders (6.3 mm diameter) impacted basalt cylinders (69 mm diameter) at speeds ranging from 0.7 to 2.0 km/s. Diagnostics included measurements of the largest fragment mass, velocities of the largest remnant and large fragments ejected from the periphery of the target, and X-ray computed tomography imaging to inspect some of the impacted targets for internal damage. Significant damage to the target occurred when the kinetic energy per unit target mass exceeded roughly 1/4 of the energy required for catastrophic shattering (where the target is reduced to one-half its original mass). Scaling laws based on a rate-dependent strength were developed that provide a basis for extrapolating the results to larger strength-dominated collisions. The threshold specific energy for widespread damage was found to scale with event size in the same manner as that for catastrophic shattering. Therefore, the factor of four difference between the two thresholds observed in the lab also applies to larger collisions. The scaling laws showed that for a sequence of collisions that are similar in that they produce the same ratio of largest fragment mass to original target mass, the fragment velocities decrease with increasing event size. As a result, rocky asteroids a couple hundred meters in diameter should retain their large ejecta fragments in a jumbled rubble-pile state. For somewhat larger bodies, the ejection velocities are sufficiently low that large fragments are essentially retained in place, possibly forming ordered "brick-pile" structures.

  20. 27. The top of a typical pile, F Reactor in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. The top of a typical pile, F Reactor in February 1945 in this case, showing the vertical safety rods (VSRs) and the cables that support them. The rods could be dropped into the pile to effect a rapid shutdown. The four silvered-colored drums on the left contained boron solution and are part of the last ditch safety system. Should the VSRs channels become blocked by an occurrence such as an earthquake, the solution could be dumped into the VSR channels to help shut down the reactor. D-8334 - B Reactor, Richland, Benton County, WA

  1. Effects of Impulsive Pile-Driving Exposure on Fishes.

    PubMed

    Casper, Brandon M; Carlson, Thomas J; Halvorsen, Michele B; Popper, Arthur N

    2016-01-01

    Six species of fishes were tested under aquatic far-field, plane-wave acoustic conditions to answer several key questions regarding the effects of exposure to impulsive pile driving. The issues addressed included which sound levels lead to the onset of barotrauma injuries, how these levels differ between fishes with different types of swim bladders, the recovery from barotrauma injuries, and the potential effects exposure might have on the auditory system. The results demonstrate that the current interim criteria for pile-driving sound exposures are 20 dB or more below the actual sound levels that result in the onset of physiological effects on fishes.

  2. Effects of Impulsive Pile-Driving Exposure on Fishes.

    PubMed

    Casper, Brandon M; Carlson, Thomas J; Halvorsen, Michele B; Popper, Arthur N

    2016-01-01

    Six species of fishes were tested under aquatic far-field, plane-wave acoustic conditions to answer several key questions regarding the effects of exposure to impulsive pile driving. The issues addressed included which sound levels lead to the onset of barotrauma injuries, how these levels differ between fishes with different types of swim bladders, the recovery from barotrauma injuries, and the potential effects exposure might have on the auditory system. The results demonstrate that the current interim criteria for pile-driving sound exposures are 20 dB or more below the actual sound levels that result in the onset of physiological effects on fishes. PMID:26610952

  3. Thermocouples For High Temperature In-Pile Testing

    SciTech Connect

    J. L. Rempe

    2005-11-01

    Many advanced nuclear reactor designs require new fuel, cladding and structural materials. Data are needed to characeterize the performance of these new materials in high temperature, oxidizing and radiation conditions. To obtain this data, robust instrumentation is needed htat can survive proposed test conditions. Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project was intiated to develop specialized thermocouples for high temperature in-pile applications (see Rempe and Wilkins, 2005). This paper summarizes efforts to develop, fabricate and evaluate these specialized thermocouples.

  4. Imagerie médicale avec des sources X créées parlaser

    NASA Astrophysics Data System (ADS)

    Dorchies, F.; Chen, L. M.; Ichalalene, Z.; Jiang, Z.; Kieffer, J. C.; Chamberlain, C. C.; Krol, A.

    2003-06-01

    L'interaction d'une impulsion laser femtoseconde avec une cible solide peut induire une émission intense de rayonnement X dans la gamme de quelques dizaines de keV. Ce type de source présente potentiellement plusieurs avantages sur les installations X conventionnelles en termes de performances (taille de la source, ganinie de longueur d'onde accessible) et de coût. Ce papier réunit les différents résultats obtenus dans le cadre du projet d'imagerie médicale de I'INRS à Varennes, Québec, Canada. Ces travaux concernent d'une part l'étude quantitative de la source de rayons X-durs: intensité, spectre et taille de la source. D'autre part. des expériences de faisabilité ont montré la pertinence de leur application à l'imagerie médicale. notamment dans le domaine de l'imagerie à grande résolution spatiale (mammographie) et dans celui de l'imagerie par soustraction d'images A deux longueurs d'onde (angiographie cardiaque). La principale limitation de ces expériences était la puissance moyenne de la source bridée par la faible cadence de l'installation laser. Les lois d'échelle déduites des expériences présentées laissent présager la poursuite de ces travaux dans des conditions cliniques réalistes avec le développement actuel de chaîne laser de hautes cadences (100Hz 1kHz).

  5. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  6. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  7. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  8. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  9. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  10. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  11. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  12. Greenhouse gas emissions during composting of dairy manure: Delaying pile mixing does not reduce overall emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of the timing of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. GHG emissions from compost piles that were mixed at 2, 3, 4, or 5 weeks after initial c...

  13. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  14. 30 CFR 56.16002 - Bins, hoppers, silos, tanks, and surge piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... MINES Materials Storage and Handling § 56.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored, handled...

  15. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  16. 30 CFR 57.16002 - Bins, hoppers, silos, tanks, and surge piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... NONMETAL MINES Materials Storage and Handling § 57.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored,...

  17. Application des codes de Monte Carlo à la radiothérapie par rayonnement à faible TEL

    NASA Astrophysics Data System (ADS)

    Marcié, S.

    1998-04-01

    In radiation therapy, there is low LET rays: photons of 60Co, photons and electrons to 4 at 25 MV created in a linac, photons 137Cs, of 192Ir and of 125I. To know the most exactly possible the dose to the tissu by this rays, software and measurements are used. With the development of the power and the capacity of computers, the application of Monte Carlo codes expand to the radiation therapy which have permitted to better determine effects of rays and spectra, to explicit parameters used in dosimetric calculation, to verify algorithms , to study measuremtents systems and phantoms, to calculate the dose in inaccessible points and to consider the utilization of new radionuclides. En Radiothérapie, il existe une variété, de rayonnements ? faible TLE : photons du cobalt 60, photons et ,électron de 4 à? 25 MV générés dans des accélérateurs linéaires, photons du césium 137, de l'iridium 192 et de l'iode 125. Pour connatre le plus exactement possible la dose délivrée aux tissus par ces rayonnements, des logiciels sont utilisés ainsi que des instruments de mesures. Avec le développement de la puissance et de la capacité, des calculateurs, l'application des codes de Monte Carlo s'est ,étendue ? la Radiothérapie ce qui a permis de mieux cerner les effets des rayonnements, déterminer les spectres, préciser les valeurs des paramètres utilisés dans les calculs dosimétriques, vérifier les algorithmes, ,étudier les systèmes de mesures et les fantomes utilisés, calculer la dose en des points inaccessibles ?à la mesure et envisager l'utilisation de nouveaux radio,éléments.

  18. 11. DETAILS: CONCRETE SHEET PILING, CORNERS #4 & #6, DWG. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAILS: CONCRETE SHEET PILING, CORNERS #4 & #6, DWG. NO. 11, 1-1/2" = 1 FT., FEB. 12, 1908, MADE BY E.C.L., APPROVED BY O.F. LACKEY - Baltimore Inner Harbor, Pier 5, South of Pratt Street between Market Place & Concord Street, Baltimore, Independent City, MD

  19. OVERVIEW OF CYANIDE PLANT REMAINS, TAILINGS PILES, PARKING LOT, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW OF CYANIDE PLANT REMAINS, TAILINGS PILES, PARKING LOT, AND MINE MANAGER'S HOME, LOOKING SOUTH SOUTHEAST. RIGHT, TAILINGS PILES ARE AT CENTER WITH CYANIDE PLANT FOUNDATIONS TO THE LEFT OF THE PILES. PARKING LOT IS AT UPPER LEFT. THE AREA BETWEEN THE COLLAPSED TANK AT CENTER LEFT AND THE REMAINS OF THE MANAGER'S HOUSE AT LOWER RIGHT IS A TAILINGS HOLDING AREA. TAILINGS FROM THE MILL WERE HELD HERE. THE LARGE SETTLING TANKS WERE CHARGED FROM THIS HOLDING AREA BY A TRAM ON RAILS AND BY A SLUICEWAY SEEN AS THE DARK SPOT ON THE CENTER LEFT EDGE OF THE FRAME. AFTER THE TAILINGS WERE LEACHED, THEY WERE DEPOSITED ON THE LARGE WASTE PILE AT CENTER RIGHT. THE TANK AT CENTER RIGHT EDGE IS WHERE THE WATER PIPELINE ENTERED THE WORKS. A STRAIGHT LINE OF POSTS IN THE GROUND GO ACROSS THE CENTER FROM LEFT TO RIGHT, WHICH ORIGINALLY SUSPENDED THE WATER PIPELINE GOING FROM THE WATER HOLDING TANK AT RIGHT UP TO THE SECONDARY WATER TANKS ABOVE THE MILL. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  20. SPH simulations of impacts on rubble pile asteroids

    NASA Astrophysics Data System (ADS)

    Deller, J.; Lowry, S.; Price, M. C.; Sierks, H.; Snodgrass, C.

    2013-09-01

    Many rubble pile asteroids with low bulk densities, like Itokawa, must include a high level of macroporosity, probably more than 40% [1]. Although little is known about their internal structure, numerical simulations of impact events on these rubble pile asteroids rely on assumptions on how the voids are distributed. While most hydrocodes do not distinguish between microand macroporosity, Benavidez et al. [2] introduced a rubble pile model where the asteroid is represented as a spherical target shell filled with an uneven distribution of basalt spheres ranging in radius from 8% to 20% of the asteroid's radius. In this study, we present a new approach to create rubble pile simulants for the use in impact simulations and quantify the dependence of impact outcomes on the internal structure of the target. The formation of the asteroid is modelled as a gravitational aggregation of spherical 'pebbles', that form the building blocks of our target. This aggregate is then converted into a high-resolution Smoothed Particle Hydrodynamics (SPH) model, which also accounts for macroporosity inside the pebbles'. To simulate high-velocity impacts on these models, we use the SPH solver in the code Autodyn. We will compare impact event outcomes for a large set of internal configurations to explore the parameter space of our model-building process. The analysis of the fragment size distribution and the disruption threshold will quantify the specific influence of each set-up parameter. This work is ongoing and we will present preliminary results at the meeting.

  1. 11. Historic drawing, Pier 10. Plan of deck and pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic drawing, Pier 10. Plan of deck and pilings, 1932. Photographic copy of original. Boston National Historical Park Archives, Charlestown Navy Yard. - Charlestown Navy Yard, Pier 10, Between Piers 9 & 11 along Mystic River on Charlestown Waterfront at eastern edge of Charlestown Navy Yard, Boston, Suffolk County, MA

  2. VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK, LOOKING WESTSOUTHWEST, BASEMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK, LOOKING WEST-SOUTHWEST, BASEMENT LEVEL -15’. EDGE O FRESONANCE TEST REACTOR (RTR), LATER KNOWN AS LATTICE TEST REACTOR (LTR), VISIBLE TO RIGHT OF PDP TANK - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  3. 8. Historic view, Pier 9. Plan of deck and pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic view, Pier 9. Plan of deck and pilings, 1932. Photographic copy of original. Boston National Historical Park Archives, Charlestown Navy Yard. - Charlestown Navy Yard, Pier 9, Between Piers 8 & 10, along Mystic River on Charlestown Waterfront at eastern edge of Navy Yard, Boston, Suffolk County, MA

  4. Suppression of Pile-Up Noise in a Jet Cone

    NASA Astrophysics Data System (ADS)

    Savine, Alexandre

    2002-01-01

    Multiple low-pT (min-bias) interactions within a beam crossing at a high luminosity hadronic collider contribute to pile-up noise in the calorimetric measurements of jets. I show how to minimize this noise by taking advantage of correlations in these background events. Substantial reductions are possible.

  5. 3. VIEW OF EMPIRE STATE MINE WITH TAILING PILE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW OF EMPIRE STATE MINE WITH TAILING PILE IN BOTTOM LEFT AND COLLAPSED ADIT LOCATED BELOW DARK SHADOWS IN FAR RIGHT/LOWER THIRD. COLLAPSED BUILDING AND PARTIAL VIEW OF ORE CHUTE/BIN IS VISIBLE ON HILLSIDE ABOVE TAILINGS. CAMERA POINTED NORTH/NORTHWEST. - Florida Mountain Mining Sites, Empire State Mine, West side of Florida Mountain, Silver City, Owyhee County, ID

  6. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  7. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  8. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  9. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  10. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... outslope of the refuse pile if required for stability, control of erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  11. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... outslope of the refuse pile if required for stability, control of erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  12. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... outslope of the refuse pile if required for stability, control or erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  13. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... outslope of the refuse pile if required for stability, control or erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  14. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... outslope of the refuse pile if required for stability, control of erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  15. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... outslope of the refuse pile if required for stability, control or erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  16. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... outslope of the refuse pile if required for stability, control or erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  17. 1. GENERAL VIEW FROM BONY PILE LOOKING SOUTH. WASH HOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW FROM BONY PILE LOOKING SOUTH. WASH HOUSE IN LEFT BACKGROUND. TIPPLE AND CLEANING PLANT TO RIGHT. IN CENTER IS A TANK USED FOR TREATING MINE REFUSE AND ACID RUNOFF. - Eureka No. 40, Tipple & Cleaning Plant, East of State Route 56, north of Little Paint Creek, Scalp Level, Cambria County, PA

  18. Enhanced In-pile Instrumentation for Material Testing Reactors

    SciTech Connect

    Joy Rempe; Darrell Knudson; Joshua Daw; Troy Unruh; Benjamin Chase; Kurt Davis; Robert Schley

    2012-07-01

    An increasing number of U.S. nuclear research programs are requesting enhanced in-pile instrumentation capable of providing real-time measurements of key parameters during irradiations. For example, fuel research and development funded by the U.S. Department of Energy now emphasize approaches that rely on first principle models to develop optimized fuel designs that offer significant improvements over current fuels. To facilitate this approach, high fidelity, real-time data are essential for characterizing the performance of new fuels during irradiation testing. Furthermore, sensors that obtain such data must be miniature, reliable and able to withstand high flux/high temperature conditions. Depending on user requirements, sensors may need to obtain data in inert gas, pressurized water, or liquid metal environments. To address these user needs, in-pile instrumentation development efforts have been initiated as part of the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF), the Fuel Cycle Research & Development (FCR&D), and the Nuclear Energy Enabling Technology (NEET) programs. This paper reports on recent INL achievements to support these programs. Specifically, an overview of the types of sensors currently available to support in-pile irradiations and those sensors currently available to MTR users are identified. In addition, recent results and products available from sensor research and development are detailed. Specifically, progress in deploying enhanced in-pile sensors for detecting elongation and thermal conductivity are reported. Results from research to evaluate the viability of ultrasonic and fiber optic technologies for irradiation testing are also summarized.

  19. Detail section extending from shore. Note the paired support pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail section extending from shore. Note the paired support pilings, concrete curbs with rectangular openings for drainage, and large-diameter metal pipe suspended under the deck. USS MISSOURI in background - U.S. Naval Base, Pearl Harbor, Gasoline Wharf, Offshore, near the intersection of Hornet Avenue & Curtis Street, Ford Island, Pearl City, Honolulu County, HI

  20. Dynamic Response of Intact Piles to Impulse Loads

    NASA Astrophysics Data System (ADS)

    Liao, Shutao T.; Roesset, Jose M.

    1997-04-01

    The objective of this work was to evaluate the theoretical capabilities of the non-destructive impact-response method in estimating the length and cross-sectional area of intact piles. Three-dimensional (3-D) axisymmetric finite element models were developed to simulate the testing. The results obtained were compared to one-dimensional solutions to evaluate the importance of 3-D effects. Extensive parametric studies were then performed on piles without defects. In each parametric study, the results from the direct use of time histories of displacements or velocities, the mobility function and the Fourier transform of the recorded displacements (impact-echo method) were compared in order to assess their relative advantages and disadvantages. The effects of the relative stiffness of the surrounding soil to that of the pile and of the embedment depth were also investigated for all three methods. In a companion paper the use of these procedures to detect defects such as bulbs (increases in the cross-sectional area of the pile) or necks (decreases in area) is studied. Int. J. Numer. Anal. Meth. Geomech., vol. 21, 255-275 (1997)

  1. Hot Spots from Dislocation Pile-up Avalanches

    NASA Astrophysics Data System (ADS)

    Armstrong, Ronald; Grise, William

    2005-07-01

    The model of hot spots developed at dislocation pile-up avalanches has been employed to explain both: greater drop- weight heights being required to initiate chemical decomposition of smaller crystals [1]; and, the susceptibility to shear banding of energetic and reference inert materials, for example, adiabatic shear banding in steel [2]. The evidence for RDX (cyclotrimethylenetrinitramine) is that few dislocations are needed in the pile-ups thus providing justification for assessing dynamic pile-up release on a numerical basis for few dislocation numbers [3]. For release from a viscous obstacle, previous and new computations lead to a local temperature plateau occurring at the origin of pile-up release [4], in line with the physical concept of a hot spot. [1] R.W. Armstrong, C.S. Coffey, V.F. DeVost and W.L. Elban, J. Appl. Phys. 68 (1990) 979. [2] R.W. Armstrong and F.J. Zerilli, Mech. Mater. 17 (1994) 319. [3] R.W. Armstrong, Proc. Eighth Intern. Seminar: New Trends in Research of Energetic Materials, April 19- 21, 2005, Pardubice, CZ. [4] W.R. Grise, NRC/AFOSR Summer Faculty Fellowship Program, AFRL/MNME, Eglin Air Force Base, FL, 2003.

  2. Airborne sound propagation over sea during offshore wind farm piling.

    PubMed

    Van Renterghem, T; Botteldooren, D; Dekoninck, L

    2014-02-01

    Offshore piling for wind farm construction has attracted a lot of attention in recent years due to the extremely high noise emission levels associated with such operations. While underwater noise levels were shown to be harmful for the marine biology, the propagation of airborne piling noise over sea has not been studied in detail before. In this study, detailed numerical calculations have been performed with the Green's Function Parabolic Equation (GFPE) method to estimate noise levels up to a distance of 10 km. Measured noise emission levels during piling of pinpiles for a jacket-foundation wind turbine were assessed and used together with combinations of the sea surface state and idealized vertical sound speed profiles (downwind sound propagation). Effective impedances were found and used to represent non-flat sea surfaces at low-wind sea states 2, 3, and 4. Calculations show that scattering by a rough sea surface, which decreases sound pressure levels, exceeds refractive effects, which increase sound pressure levels under downwind conditions. This suggests that the presence of wind, even when blowing downwind to potential receivers, is beneficial to increase the attenuation of piling sound over the sea. A fully flat sea surface therefore represents a worst-case scenario. PMID:25234870

  3. The impact of wind energy turbine piles on ocean dynamics

    NASA Astrophysics Data System (ADS)

    Grashorn, Sebastian; Stanev, Emil V.

    2016-04-01

    The small- and meso-scale ocean response to wind parks has not been investigated in the southern North Sea until now with the help of high-resolution numerical modelling. Obstacles such as e.g. wind turbine piles may influence the ocean current system and produce turbulent kinetic energy which could affect sediment dynamics in the surrounding area. Two setups of the unstructured-grid model SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) have been developed for an idealized channel including a surface piercing cylindrical obstacle representing the pile and a more realistic test case including four exemplary piles. Experiments using a constant flow around the obstacles and a rotating M2 tidal wave are carried out. The resulting current and turbulence patterns are investigated to estimate the influence of the obstacles on the surrounding ocean dynamics. We demonstrate that using an unstructured ocean model provides the opportunity to embed a high-resolution representation of a wind park turbine pile system into a coarser North Sea setup, which is needed in order to perform a seamless investigation of the resulting geophysical processes.

  4. 61. Picking Floor, Large Pile of Waste Rock and Wood ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. Picking Floor, Large Pile of Waste Rock and Wood date unknown Historic Photograph, Photographer Unknown; Collection of William Everett, Jr. (Wilkes-Barre, PA), photocopy by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

  5. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; construction requirements. 77.215 Section 77.215 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... controlling or extinguishing a fire. (c) Clay or other sealants shall be used to seal the surface of...

  6. Behavior of pile group with elevated cap subjected to cyclic lateral loads

    NASA Astrophysics Data System (ADS)

    Chen, Yun-min; Gu, Ming; Chen, Ren-peng; Kong, Ling-gang; Zhang, Zhe-hang; Bian, Xue-cheng

    2015-06-01

    The pile group with elevated cap is widely used as foundation of offshore structures such as turbines, power transmission towers and bridge piers, and understanding its behavior under cyclic lateral loads induced by waves, tide water and winds, is of great importance to designing. A large-scale model test on 3×3 pile group with elevated cap subjected to cyclic lateral loads was performed in saturated silts. The preparation and implementation of the test is presented. Steel pipes with the outer diameter of 114 mm, thickness of 4.5 mm, and length of 6 m were employed as model piles. The pile group was cyclic loaded in a multi-stage sequence with the lateral displacement controlled. In addition, a single pile test was also conducted at the same site for comparison. The displacement of the pile cap, the internal forces of individual piles, and the horizontal stiffness of the pile group are presented and discussed in detail. The results indicate that the lateral cyclic loads have a greater impact on pile group than that on a single pile, and give rise to the significant plastic strain in the soil around piles. The lateral loads carried by each row of piles within the group would be redistributed with loading cycles. The lateral stiffness of the pile group decreases gradually with cycles and broadly presents three different degradation patterns in the test. Significant axial forces were measured out in some piles within the group, owing to the strong restraint provided by the cap, and finally lead to a large settlement of the pile group. These findings can be referred for foundation designing of offshore structures.

  7. Field monitoring of static, dynamic, and statnamic pile loading tests using fibre Bragg grating strain sensors

    NASA Astrophysics Data System (ADS)

    Li, Jin; Correia, Ricardo P.; Chehura, Edmon; Staines, Stephen; James, Stephen W.; Tatam, Ralph; Butcher, Antony P.; Fuentes, Raul

    2009-10-01

    Pile loading test plays an important role in the field of piling engineering. In order to gain further insight into the load transfer mechanism, strain gauges are often used to measure local strains along the piles. This paper reports a case whereby FBG strain sensors was employed in a field trial conducted on three different types of pile loading tests in a glacial till. The instrumentation systems were configured to suit the specific characteristic of each type of test. Typical test results are presented. The great potential of using FBG sensors for pile testing is shown.

  8. Evaluation of in-pile and out-of-pile stress relaxation in 316L stainless steel under uniaxial loading

    NASA Astrophysics Data System (ADS)

    Kaji, Yoshiyuki; Miwa, Yukio; Tsukada, Takashi; Kikuchi, Masahiko; Kita, Satoshi; Yonekawa, Minoru; Nakano, Junichi; Tsuji, Hirokazu; Nakajima, Hajime

    2002-12-01

    Stress relaxation of tensile type specimens under fast neutron irradiation at 288 °C has been studied for 316L stainless steel (SS) in the Japan Materials Testing Reactor. In-pile stress-relaxation tests were carried out at fast neutron fluence levels of 1.3×10 24, 5.5×10 24 and 1.5×10 25 n/m 2 ( E>1 MeV). These tests were carried out at the applied total strain levels of 0.06%, 0.1%, 0.3% and 0.75%. In order to evaluate the thermal stress-relaxation behavior and to distinguish it from the irradiation induced stress-relaxation behavior, out-of-pile stress-relaxation tests were also performed at 288 °C in air using an electric furnace. This paper describes results of in-pile and out-of-pile stress-relaxation tests on 316L SS tensile specimens. These results are compared with the literature data by Foster et al. [J. Nucl. Mater. 252 (1998) 89] which were mainly obtained from bend beam specimens. Moreover, these experimental results are compared with analytical results obtained using Nagakawa's model [J. Nucl. Mater. 212-215 (1994) 541].

  9. An experimental study on pile spacing effects under lateral loading in sand.

    PubMed

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand.

  10. An experimental study on pile spacing effects under lateral loading in sand.

    PubMed

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand. PMID:24453900

  11. An Experimental Study on Pile Spacing Effects under Lateral Loading in Sand

    PubMed Central

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand. PMID:24453900

  12. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    SciTech Connect

    Silva, I. Matias; Combe, Gaeel; Foray, Pierre; Flin, Frederic; Lesaffre, Bernard

    2013-06-18

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 {mu}m were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  13. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    NASA Astrophysics Data System (ADS)

    Silva, I. Matías; Combe, Gaël; Foray, Pierre; Flin, Frédéric; Lesaffre, Bernard

    2013-06-01

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 μm were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  14. Des ballons pour demain

    NASA Astrophysics Data System (ADS)

    Régipa, R.

    A partir d'une théorie sur la détermination des formes et des contraintes globales d'un ballon de révolution, ou s'en rapprochant, une nouvelle famille de ballons a été définie. Les ballons actuels, dits de ``forme naturelle'', sont calculés en général pour une tension circonférencielle nulle. Ainsi, pour une mission donnée, la tension longitudinale et la forme de l'enveloppe sont strictement imposées. Les ballons de la nouvelle génération sont globalement cylindriques et leurs pôles sont réunis par un câble axial, chargé de transmettre une partie des efforts depuis le crochet (pôle inférieur), directement au pôle supérieur. De plus, la zone latérale cylindrique est soumise à un faible champ de tensions circonférencielles. Ainsi, deux paramètres permettent de faire évoluer la distribution des tensions et la forme de l'enveloppe: - la tension du câble de liaison entre pôles (ou la longueur de ce câble) - la tension circonférencielle moyenne désirée (ou le rayon du ballon). On peut donc calculer et réaliser: - soit des ballons de forme adaptée, comme les ballons à fond plat pour le bon fonctionnement des montgolfières infrarouge (projet MIR); - soit des ballons optimisés pour une bonne répartition des contraintes et une meilleure utilisation des matériaux d'enveloppe, pour l'ensemble des programmes stratosphériques. Il s'ensuit une économie sensible des coûts de fabrication, une fiabilité accrue du fonctionnement de ces ballons et une rendement opérationnel bien supérieur, permettant entre autres, d'envisager des vols à très haute altitude en matériaux très légers.

  15. Impact simulations on the rubble pile asteroid (2867) Steins

    NASA Astrophysics Data System (ADS)

    Deller, Jakob; Lowry, Stephen; Snodgrass, Colin; Price, Mark; Sierks, Holger

    2015-04-01

    Images from the OSIRIS camera system on board the Rosetta spacecraft (Keller et al. 2010) have revealed several interesting features on asteroid (2867) Steins. Its macro porosity of 40%, together with the shape that looks remarkably like a YORP evolved body, both indicate a rubble pile structure. A large crater on the southern pole is evidence for collisional evolution of this rubble pile asteroid. We have developed a new approach for simulating impacts on asteroid bodies that connects formation history to their collisional evolution. This is achieved by representing the interior as a 'rubble pile', created from the gravitational aggregation of spherical 'pebbles' that represent fragments from a major disruption event. These 'pebbles' follow a power-law size function and constitute the building blocks of the rubble pile. This allows us to explicitly model the interior of rubble pile asteroids in hyper-velocity impact simulations in a more realistic way. We present preliminary results of a study validating our approach in a large series of simulated impacts on a typical small main-belt rubble pile asteroid using the Smoothed Particle Hydrodynamics solver in LS-DYNA. We show that this approach allows us to explicitly follow the behavior of a single 'pebble', while preserving the expected properties of the bulk asteroid as known from observations and experiments (Holsapple 2009). On the example of Steins, we use this model to relate surface features like the northern hill at 75/100 degrees lon/lat distance to the largest crater (Jorda et al. 2012), or the catena of depletion pits, to the displacement of large fragments in the interior of the asteroid during the impact. We do this by following the movement of pebbles below the surface feature in simulations that recreate the shape of the impact crater. We show that while it is not straightforward to explain the formation of the hill-like structure, the formation of cracks possibly leading to depletion zones can be

  16. Picking up Clues from the Discard Pile (Stereo)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil.

    On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through its left eye and right eye that have been combined into this stereo view. The image appears three dimensional when seen through red-blue glasses.

    This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench.

    Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches.

    For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench.

    The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA

  17. Traitement chirurgical initial des brûlures de la main de l’enfant. Revue

    PubMed Central

    Goffinet, L.; Breton, A.; Gavillot, C.; Barbary, S.; Journeau, P.; Lascombes, P.; Dautel, G.

    2015-01-01

    Summary Trente cinq revues concernant la prise en charge chirurgicale de la main brûlée de l’enfant sont indexées dans Pub- Med. Elles portent sur l’indication de la cicatrisation dirigée versus chirurgie, les techniques et délais d’instauration des traitements par excision-greffe, le calendrier et la nature du traitement de réadaptation et la surveillance. L’enfant présente un risque accru de brides cicatricielles, nécessitant un suivi médico-chirurgical attentif et prolongé. L’objet de cet article est de rapporter les spécificités chirurgicales de la prise en charge de ces brûlures. Cette revue de la littérature, réalisée au moyen de la base PubMed (publication entre 2005 et 2011) à partir des mots-clés « hand AND/OR child AND/OR burn » retrouve 67 publications utiles au sein de 171 références. Les données rapportées ont été comparées aux ouvrages de références français et américains. Des données contradictoires sont rapportées concernant la délai de l’excision et de la greffe, avec seulement deux études comparatives comportant de nombreux biais. L’état de la science n’apporte pas d’éléments de preuve suffisant en raison d’un manque de puissance statistique des études, mais de nombreux avis d’expert explorant chaque type d’indication permet d’établir une stratégie claire, guidant les indications thérapeutiques. Il apparaît donc indispensable de réaliser des études prospectives incluant ces patients depuis le suivi initial jusqu’au suivi à long terme, pour augmenter le niveau de preuve de cette stratégie. PMID:27279807

  18. Development of a geotechnical and pile driving database, Adriatic Sea

    SciTech Connect

    Carpaneto, R.; Paoletti, L.; Guaita, P.; Pratico, A.

    1996-12-31

    The paper presents a geotechnical and pile driving data base relevant to offshore installations in the Adriatic Sea. The paper discusses sources of information, structure, content, and engineering applications of the data base. Data available from Agip`s platform installations in the Adriatic was reviewed, and 20 representative platforms were chosen. Two relational data bases were created, for geotechnical and installation data respectively. The data bases provide a comprehensive and organized source of information about past experience in the area. Such experience is now quickly available for geotechnical engineering activities. As a main application of the data bases, information was processed to make data sets for training Artificial Neural Networks (ANN) to predict pile driveability. It is envisioned that the data bases will also be used in ongoing installation program design.

  19. The Supercritical Pile Model: Prompt Emission Across the Electromagnetic Spectrum

    NASA Technical Reports Server (NTRS)

    Kazanas, Demos; Mastichiadis, A.

    2008-01-01

    The "Supercritical Pile" GRB model is an economical model that provides the dissipation necessary to convert explosively the energy stored in relativistic protons in the blast wave of a GRB into radiation; at the same time it produces spectra whose luminosity peaks at 1 MeV in the lab frame, the result of the kinematics of the proton-photon - pair production reaction that effects the conversion of proton energy to radiation. We outline the fundamental notions behind the "Supercritical Pile" model and discuss the resulting spectra of the prompt emission from optical to gamma-ray energies of order Gamma^2 m_ec^2, (Gamma is the Lorentz factor of the blast wave) present even in the absence of an accelerated particle distribution and compare our results to bursts that cover this entire energy range. Particular emphasis is given on the emission at the GLAST energy range both in the prompt and the afterglow stages of the burst.

  20. High Temperature Thermocouples For In-pile Applications

    SciTech Connect

    J. L. Rempe; S. C. Wilkins

    2005-10-01

    Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project has been initiated to explore the use of specialized thermocouples that are composed of materials that are able to withstand higher temperature, in-pile test conditions. Results from efforts to develop, fabricate and evaluate the performance of these specialized thermocouples are reported in this paper. Candidate materials were evaluated for their ability to withstand irradiation, to resit material interactions and to remain ductile at high temperatures. In addition, candidate thermocouples were evaluated based on their resolution over the temperature ranges of interest. Results from these evaluations are reported, and additional on-going development activities are summarized.

  1. New Analysis Techniques for Avalanches in a Conical Bead Pile with Cohesion

    NASA Astrophysics Data System (ADS)

    Tieman, Catherine; Lehman, Susan

    2015-03-01

    Avalanche statistics and pile geometry for 3 mm steel spheres dropped on a conical bead pile were studied at different drop heights and different cohesion strengths. The pile is initially built on a circular base and is subsequently slowly driven by adding one bead at a time to the apex of the pile. We investigate the dynamic response of the pile by recording avalanches off the pile over the course of tens of thousands of bead drops. The level of cohesion is tuned through use of an applied uniform magnetic field. Changes in the pile mass and geometry were investigated to determine the effect of cohesion and drop height on the angle of repose. The angle of repose increased with cohesion strength, and decreased somewhat for higher drop heights. The packing density of beads is expected to decrease as magnetic cohesion increases, but for our 20 000-bead pile, this effect has not been observed. The proportion of beads removed from the pile by different avalanche sizes was also calculated. Although larger avalanches are much rarer occurrences, they carry away a larger fraction of the total avalanched mass than small avalanches. As the pile cohesion increases, the number of small and medium avalanches decreases so that this mass loss distribution shifts more strongly to large sizes.

  2. Vegetative cover grows directly on acidic mine refuse pile

    SciTech Connect

    Nickeson, F.H.

    1984-02-01

    The paper reports how permanent, self-sustaining vegetation has been established on an acidic, 80-year old coal refuse pile without using a soil cover. Tests were carried out on a number of 1-acre plots which were treated with different mixtures of lime, fertiliser and seeds of grasses and legumes. The results of the tests are discussed and the way in which the final treatment was chosen is explained. The work is considered to have been successful.

  3. Chestnut Ridge Borrow Area Waste Pile work plan

    SciTech Connect

    Johnson, R. )

    1991-08-01

    The US Department of Energy (DOE), through its contractor Martin Marietta Energy Systems, Inc., has constructed a storage facility, the Chestnut Ridge Borrow Area Waste Pile (CRBAWP), for mercury-contaminated soil excavated from the Oak Ridge Civic Center properties and the Oak Ridge Sewer Line Beltway. Excavation of the soil from the Civic Center began in September 1984 and was completed in early 1985. Similar soils from other areas of the city were added to the pile until 1987. Approximately 3000 yd{sup 3} are stored at the present time. An Interim Status RCRA permit was initially sought for this facility. Samples from the waste pile passed the Extraction Procedure Toxicity Test (EP Tox). The Tennessee Department of Health and Environment (now the Tennessee Department of Conservation-TDC) denied the permit based on their conclusion that the waste was not a RCRA-regulated waste. On September 25, 1990 the Toxicity Characteristic Leaching Procedure (TCLP) superseded the EP Tox test. TCLP tests are not proposed to satisfy a request by TDC and to make a final determination of the nature of the soils in order to close the CRBAWP as a solid waste disposal facility under Tennessee State rule 1200-1-7-.04. The objectives of this work are to summarize existing site information and detail actions necessary to sample and characterize soils from the waste pile as hazardous or nonhazardous per the Toxicity Characteristic Leaching Procedure (TCLP). Within the scope of this plan, a site investigation will be discussed; a field sampling plan will be described in terms of sampling locations, procedures, and quality assurance; and ancillary activities such as waste management, data management, and health and safety will be outlines. 15 refs., 7 figs., 2 tabs.

  4. Analytical Constraints on Rubble Pile Fission, Dynamics and End States

    NASA Astrophysics Data System (ADS)

    Scheeres, Daniel Jay; Gabriel, Travis

    2015-08-01

    Recent progress in the study and analysis of rubble pile asteroids has focused on the numerical simulation of self-gravitating collections of rigid components that can rest on each other. These simulations are complex and can model thousands of grains interacting with each other, but due to this can sometimes present barriers to the understanding of their behavior in terms of fundamental physical principles.To address this we have embarked on an analytical study of the energetics and stability of few-body granular mechanics systems, comprised of gravitationally attracting elements that can rest on each other and transmit surface forces through friction or cohesion. These studies have primarily focused on simple shapes such as spheres and ellipsoids in contact. We have found that rigorous results can be placed on the stability of these resting and orbiting configurations as a function of their total angular momentum. These results shed direct light into the manner in which rubble pile asteroids can fail and what stable configurations they can settle in, accounting only for internal forces and dynamics. We note that these studies are also applicable for the accumulation stage of a rubble pile formation, following the catastrophic disruption of its parent body.There are several fundamental results from these analyses that have physical implications. A notable result provides conditions for when fissioned rubble piles can escape from each other, or conversely remain bound. It is significant that recent observations of asteroid pairs are consistent with these limits. Another result is that when a given configuration becomes unstable due to an increase in its total angular momentum (for example due to YORP), that it may sometimes settle into one of several stable configurations depending on how its energy is dissipated. This introduces a level of indeterminacy into the physical evolution of gravitational aggregates, and motivates the development of statistical approaches

  5. Pile response to lateral spread: A benchmark case

    SciTech Connect

    Chaudhuri, D.; Toprak, S.; O`Rourke, T.D.

    1995-12-31

    The paper compares analytical results with field observations of piles damaged during the 1964 Niigata earthquake. Three different models for liquefied soil-structure interaction are used, including two subgrade reaction models with both drained and undrained strength parameters and a model to account for the viscosity of liquefied soil. The subgrade reaction model provides for the bet agreement between analytical and observed behavior. Recommendations are made for selecting the most appropriate drained and undrained parameters for analysis and design.

  6. Carbon Emissions from Residue Burn Piles Estimated Using LiDAR or Ground Based Measurements of Pile Volumes in a Coastal Douglas-Fir Forest

    NASA Astrophysics Data System (ADS)

    Trofymow, J. A.; Coops, N.; Hayhurst, D.

    2012-12-01

    Following forest harvest, residues left on site and roadsides are often disposed of to reduce fire risk and free planting space. In coastal British Columbia burn piles are the main method of disposal, particularly for accumulations from log processing. Quantification of residue wood in piles is required for: smoke emission estimates, C budget calculations, billable waste assessment, harvest efficiency monitoring, and determination of bioenergy potentials. A second-growth Douglas-fir dominated (DF1949) site on eastern Vancouver Island and subject of C flux and budget studies since 1998, was clearcut in winter 2011, residues piled in spring and burned in fall. Prior to harvest, the site was divided into 4 blocks to account for harvest plans and ecosite conditions. Total harvested wood volume was scaled for each block. Residue pile wood volume was determined by a standard Waste and Residue Survey (WRS) using field estimates of pile base area and plot density (wood volume / 0.005 ha plot) on 2 piles per block, by a smoke emissions geometric method with pile volumes estimated as ellipsoidal paraboloids and packing ratios (wood volume / pile volume) for 2 piles per block, as well as by five other GIS methods using pile volumes and areas from LiDAR and orthophotography flown August 2011, a LiDAR derived digital elevation model (DEM) from 2008, and total scaled wood volumes of 8 sample piles disassembled November 2011. A weak but significant negative relationship was found between pile packing ratio and pile volume. Block level avoidable+unavoidable residue pile wood volumes from the WRS method (20.0 m3 ha-1 SE 2.8) were 30%-50% of the geometric (69.0 m3 ha-1 SE 18.0) or five GIS/LiDAR (48.0 to 65.7 m3 ha-1 ) methods. Block volumes using the 2008 LiDAR DEM (unshifted 48.0 m3 ha-1 SE 3.9, shifted 53.6 m3 ha-1 SE 4.2) to account for pre-existing humps or hollows beneath piles were not different from those using the 2011 LiDAR DEM (50.3 m3 ha-1 SE 4.0). The block volume ratio

  7. Pipelines and laterally loaded piles in elastoplastic medium

    SciTech Connect

    Rajani, B. . Inst. for Research in Construction)

    1993-09-01

    The uplift behavior of a shallow pipeline embedded in an elastoplastic medium is examined. An analytical solution for a beam on elastoplastic foundation is developed and a characteristic nondimensional load-displacement and stress-displacement relationship are presented. An approximate three-dimensional (3D) solution is proposed that accounts for embedment and breakaway condition behind the pipeline making use of the load-displacement curves developed for rigid anchors by Rowe and Davis in 1982. A comparison of these results with those obtained by 3D finite-element analysis indicates that the simplified solution of a beam on elastoplastic foundation is a practical alternative for analyzing the uplift behavior of shallow pipelines. The approximate solution is also used to compare the behavior of a laterally loaded pile for which no separation or separation between the surrounding soil and the back of the pile is permitted as the load is monotonically increased. The results are presented in the form of nondimensional charts that permit hand calculations and rapid verification of structural design of the pipeline and piles.

  8. NEET In-Pile Ultrasonic Sensor Enablement-Final Report

    SciTech Connect

    J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

    2014-09-01

    Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

  9. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    SciTech Connect

    Joy Rempe; Darrell Knudson; Joshua Daw; Troy Unruh; Benjamin Chase; Kurt Davis; Robert Schley; Steven Taylor

    2012-08-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory. To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility in 2007 to support the development and deployment of enhanced in-pile sensors. This paper provides an update on this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  10. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    SciTech Connect

    J. Rempe; D. Knudson; J. Daw; T. Unruh; B. Chase; K. Condie

    2011-06-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility (NSUF) in 2007 to support the development and deployment of enhanced in-pile sensors. This paper reports results from this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  11. Radiocarbon from Pile Graphite; Chemical Methods for Its Concentrations

    DOE R&D Accomplishments Database

    Arnold, J. R.; Libby, W. F.

    1946-10-10

    Samples of pile graphite, irradiated in a test-hole at Hanford for 15 months, have been assayed for radioactive C{sup 14} yielding 0.38 ± 0.04 microcuries per gram. At this level of activity, the pile graphite contains very valuable amounts of C{sup14}. The relation between the above assay and the probable average assay of pile graphite is discussed, and it is concluded that the latter is almost certainly above 0.3 microcuries/gram. Controlled oxidation of this graphite, either with oxygen at ~750ºC, or with chromic acid "cleaning solution" at room temperature, yields early fractions which are highly enriched in C{sup 14}. Concentrations of 5-fold with oxygen, and 50-fold with CrO{sub 3}, have been observed. The relation between the observed enrichment and the Wigner effect is discussed, and a mechanism accounting for the observations put forward. According to this, about 25% of the stable carbon atoms in the lattice have been displaced by Wigner effect, a large fraction of which have healed by migrating to crystal edges. All the C{sup 14} atoms have been displaced, and the same fraction of these migrate to the edges. The enrichment then results from surface oxidation, in the oxygen case. Predictions are made on the basis of this hypothesis. A technique of counting radioactive CO{sub 2} in the gas phase is described.

  12. Impact Simulations on the Rubble Pile Asteroid (2867) Steins

    NASA Astrophysics Data System (ADS)

    Deller, Jakob; Snodgrass, Colin; Lowry, Stephen C.; Price, Mark C.; Sierks, Holger

    2014-11-01

    Images from the OSIRIS camera system on board the Rosetta spacecraft (Keller et al. 2010) has revealed several interesting features on asteroid (2867) Steins. Its macro porosity of 40%, together with the shape that looks remarkably like a YORP evolved body, both indicate a rubble pile structure. A large crater on the southern pole is evidence for collisional evolution of this rubble pile asteroid. We have developed a new approach for simulating impacts on asteroid bodies that connects formation history to their collisional evolution. This is achieved by representing the interior as a ‘rubble pile’, created from the gravitational aggregation of spherical ‘pebbles’ that represent fragments from a major disruption event. These ‘pebbles’ follow a power law size function and constitute the building blocks of the rubble pile. This allows us to explicitly model the interior of rubble pile asteroids in hyper-velocity impact simulations in a more realistic way. We present preliminary results of a study validating our approach in a large series of simulated impacts on a typical small main belt rubble pile asteroid using the Smoothed Particle Hydrodynamics solver in Autodyn. We show that this approach allows us to explicitly follow the behavior of a single ‘pebble’, while preserving the expected properties of the bulk asteroid as known from observations and experiments (Holsapple 2009). On the example of Steins, we use this model to investigate if surface features like the northern hill at 75/100 degrees lon/lat distance to the largest crater (Jorda et al. 2012), or the catena of depletion pits, can be explained by the displacement of large fragments in the interior of the asteroid during the impact. We do this by following the movement of pebbles below the surface feature in simulations that recreate the shape of the impact crater.Acknowledgements: Jakob Deller thanks the Planetary Science Institute for a Pierazzo International Student Travel Award that funds

  13. Design of passively aerated compost piles: Vertical air velocities between the pipes

    SciTech Connect

    Lynch, N.J.; Cherry, R.S.

    1996-09-01

    Passively aerated compost piles are built on a base of porous materials, such as straw or wood chips, in which perforated air supply pipes are distributed. The piles are not turned during composting, nor is forced-aeration equipment used, which significantly reduces the operating and capital expenses associated with these piles. Currently, pile configurations and materials are worked out by trial and error. Fundamentally based design procedures are difficult to develop because the natural convection air flow rate is not explicitly known, but rather is closely coupled with the pile temperature. This paper develops a mathematical model to analytically determine the maximum upward air flow velocity over an air supply pipe and the drop in vertical velocity away from the pipe. This model has one dimensionless number, dependent on the pile and base properties, which fully characterizes the velocity profile between the pipes. 9 refs., 4 figs., 1 tab.

  14. Numerical modeling of Thermal Response Tests in Energy Piles

    NASA Astrophysics Data System (ADS)

    Franco, A.; Toledo, M.; Moffat, R.; Herrera, P. A.

    2013-05-01

    Nowadays, thermal response tests (TRT) are used as the main tools for the evaluation of low enthalpy geothermal systems such as heat exchangers. The results of TRT are used for estimating thermal conductivity and thermal resistance values of those systems. We present results of synthetic TRT simulations that model the behavior observed in an experimental energy pile system, which was installed at the new building of the Faculty of Engineering of Universidad de Chile. Moreover, we also present a parametric study to identify the most influent parameters in the performance of this type of tests. The modeling was developed using the finite element software COMSOL Multiphysics, which allows the incorporation of flow and heat transport processes. The modeled system consists on a concrete pile with 1 m diameter and 28 m deep, which contains a 28 mm diameter PEX pipe arranged in a closed circuit. Three configurations were analyzed: a U pipe, a triple U and a helicoid shape implemented at the experimental site. All simulations were run considering transient response in a three-dimensional domain. The simulation results provided the temperature distribution on the pile for a set of different geometry and physical properties of the materials. These results were compared with analytical solutions which are commonly used to interpret TRT data. This analysis demonstrated that there are several parameters that affect the system response in a synthetic TRT. For example, the diameter of the simulated pile affects the estimated effective thermal conductivity of the system. Moreover, the simulation results show that the estimated thermal conductivity for a 1 m diameter pile did not stabilize even after 100 hours since the beginning of the test, when it reached a value 30% below value used to set up the material properties in the simulation. Furthermore, we observed different behaviors depending on the thermal properties of concrete and soil. According to the simulations, the thermal

  15. Numerical simulations of shake-table experiment for dynamic soil-pile-structure interaction in liquefiable soils

    NASA Astrophysics Data System (ADS)

    Tang, Liang; Maula, Baydaa Hussain; Ling, Xianzhang; Su, Lei

    2014-03-01

    A shake-table experiment on pile foundations in liquefiable soils composed of liquefiable sand and overlying soft clay is studied. A three-dimensional (3D) effective stress finite element (FE) analysis is employed to simulate the experiment. A recently developed multi-surface elasto-plastic constitutive model and a fully coupled dynamic inelastic FE formulation ( u- p) are used to model the liquefaction behavior of the sand. The soil domains are discretized using a solid-fl uid fully coupled ( u- p) 20-8 noded brick element. The pile is simulated using beam-column elements. Upon careful calibration, very good agreement is obtained between the computed and the measured dynamic behavior of the ground and the pile. A parametric analysis is also conducted on the model to investigate the effect of pile-pinning, pile diameter, pile stiffness, ground inclination angle, superstructure mass and pile head restraints on the ground improvement. It is found that the pile foundation has a noticeable pinning effect that reduces the lateral soil displacement. It is observed that a larger pile diameter and fixed pile head restraints contribute to decreasing the lateral pile deformation; however, a higher ground inclination angle tends to increase the lateral pile head displacements and pile stiffness, and superstructure mass seems to effectively influence the lateral pile displacements.

  16. Avalanches in One-Dimensional Piles with Different Types of Bases

    SciTech Connect

    Altshuler, E.; Ramos, O.; Martinez, C.; Flores, L. E.; Noda, C.

    2001-06-11

    We perform a systematic experimental study of the influence of the type of base on the avalanche dynamics of slowly driven 1D ball piles. The control of base details allows us to explore a wide spectrum of pile structures and dynamics. The scaling properties of the observed avalanche distributions suggest that self-organized critical behavior is approached as the {open_quotes}base-induced{close_quotes} disorder at the pile profile increases.

  17. Design of anti-slide piles for slope stabilization in Wanzhou city, Three Gorges Area, China

    NASA Astrophysics Data System (ADS)

    Zhou, Chunmei; van Westen, Cees

    2013-04-01

    This study is related to the design of anti-slide piles for several landslides in Wanzhou city located in the Three Gorges area. Due to the construction of the Three Gorges Reservoir the hydro-geological conditions in this area have deteriorated significantly, leading to larger instability problems. China has invested a lot of money in slope stabilization measures for the treatment of landslides in the Three Gorges area. One of the methods for the stabilization of large landslides is the design of anti-sliding piles. This paper focuses on extensive slope stability analysis and modeling of the mechanical behavior of the landslide masses, and the parameters required for designing the number, size and dimensions of reinforced concrete stabilization piles. The study focuses on determining the rock parameters, anchor depth, and the pile and soil interaction coefficient. The study aims to provide guidelines for anti-slide pile stabilization works for landslides in the Wanzhou area. The research work contains a number of aspects. First a study is carried out on the distribution of pressures expected on the piles, using two different methods that take into account the expected pore water pressure and seismic acceleration. For the Ercengyan landslide , the Limit Equilibrium Method and Strength Reduction Method of FEM are compared through the results of the landslide pressure distributions on the piles and stress fields in the piles. The second component is the study of the required anchor depth of antislide piles, which is carried out using a statistical analysis with data from 20 landslides that have been controlled with anti-sliding piles. The rock characteristics of the anchor locations were obtained using laboratory tests, and a classification of rock mass quality is made for the anchors of antislide piles. The relationship between the critical anchor height and the angle of the landslide slip surface is determined. Two different methods are presented for the length

  18. Experimental and numerical investigation on the dynamic response of pile group in liquefying ground

    NASA Astrophysics Data System (ADS)

    Tang, Liang; Zhang, Xiaoyu; Ling, Xianzhang; Li, Hui; Ju, Nengpan

    2016-03-01

    The response of pile foundation in liquefiable sand reinforced by densification techniques remains a very complex problem during strong earthquakes. A shake-table experiment was carried out to investigate the behavior of a reinforced concrete low-cap pile group embedded in this type of ground. In this study, a three-dimensional (3D) finite element (FE) analysis of the experiment was conducted. The computed response of the soil-pile system was in reasonable agreement with the experimental results, highlighting some key characteristics. Then, a parametric study was performed to explore the influence of pile spacing, pile stiffness ( EI), superstructure mass, sand permeability, and shaking characteristics of input motion on the behavior of the pile. The investigation demonstrated a stiffening behavior appearing in the liquefied mediumdense sand, and the pile group effect seemed negligible. Furthermore, the kinematic effect was closely connected with both EI and sand permeability. Nevertheless, the inertial effect was strongly influenced by the superstructure mass. Meanwhile, high frequency and large amplitude of the input motion could produced greater the pile's moments. It is estimated that this case study could further enhance the current understanding of the behavior of low-cap pile foundations in liquefied dense sand.

  19. Application of CFG Piles to Soft Soil Treatment of Municipal Engineering

    NASA Astrophysics Data System (ADS)

    Xu, Qingli; Song, Yan; Han, Xinzhan

    With rapid development of constructional engineering, methods used for soft soil foundation treatment become increasingly diversified. Because composite foundation has the peculiar advantage that that it makes full use of earth among piles and piles and is featured by short construction period, large treatment depth and relatively good effect, it has been applied more and more widely. The engineering applies CFG pipes, utilizes high bearing capacity of piles and gives full play to carrying capacity of earth among piles by establishing a mattress layer.

  20. Etude de la Morphologie et de la Cinématique de l'Emission des Raies interdites autour des Etoiles T Tauri

    NASA Astrophysics Data System (ADS)

    Lavalley, Claudia

    2000-06-01

    Le phénomène de perte de masse joue un rôle essentiel dès les premières étapes de la formation stellaire et semble être intimement lié à l'accrétion de matière sur l'étoile, probablement par l'intermédiaire de champs magnétiques permettant de convertir l'énergie cinétique accrétée, en puissance d'éjection. Les étoiles T Tauri classiques, âgées de quelques millions d'années et présentant une faible extinction, offrent un excellent cadre pour étudier les régions internes des vents stellaires. Dans ce travail, je présente les premières études sur la morphologie des jets associés aux étoiles DG Tau, CW Tau et RW Aur à une résolution angulaire de 0.1'' et sur la cinématique à deux dimensions de l'émission des raies de [O I]?6300Å, [N II]?6583Å et [S II] ?6716,6731Å dans le jet de DG Tau. Ces données ont été obtenues avec deux techniques d'observation complètement nouvelles, devenues disponibles entre 1994 et 1998 au télescope CFH, et idéalement adaptées à ce problème: l'imagerie en bande étroite derrière l'optique adaptative (PUEO) qui fournit des données à très haute résolution angulaire (~0.1''), et la spectro-imagerie intégrale de champ (TIGRE/OASIS) qui donne accès à l'information spatiale et spectrale à 2D, à haute résolution angulaire (ici ~0.5''-0.75'') et moyenne résolution spectrale (100-170 km/s). Les trois jets étudiés, résolus pour la première fois à partir de 55 u.a. de l'étoile, présentent une largeur similaire (30-35 u.a.) jusqu'à 100 u.a. et une morphologie dominée par des noeuds d'émission. Les jets des étoiles à faible excès infrarouge CW Tau et RW Aur sont très similaires aux deux autres jets des sources peu enfouies observés jusqu'à présent à la même échelle spatiale. Le jet de DG Tau, plus perturbé que les deux autres, et provenant d'une source avec une enveloppe encore importante, est aussi très similaire au seul autre jet associé à une source encore enfouie r

  1. Pile-Up Discrimination Algorithms for the HOLMES Experiment

    NASA Astrophysics Data System (ADS)

    Ferri, E.; Alpert, B.; Bennett, D.; Faverzani, M.; Fowler, J.; Giachero, A.; Hays-Wehle, J.; Maino, M.; Nucciotti, A.; Puiu, A.; Ullom, J.

    2016-07-01

    The HOLMES experiment is a new large-scale experiment for the electron neutrino mass determination by means of the electron capture decay of ^{163}Ho. In such an experiment, random coincidence events are one of the main sources of background which impair the ability to identify the effect of a non-vanishing neutrino mass. In order to resolve these spurious events, detectors characterized by a fast response are needed as well as pile-up recognition algorithms. For that reason, we have developed a code for testing the discrimination efficiency of various algorithms in recognizing pile up events in dependence of the time separation between two pulses. The tests are performed on simulated realistic TES signals and noise. Indeed, the pulse profile is obtained by solving the two coupled differential equations which describe the response of the TES according to the Irwin-Hilton model. To these pulses, a noise waveform which takes into account all the noise sources regularly present in a real TES is added. The amplitude of the generated pulses is distributed as the ^{163}Ho calorimetric spectrum. Furthermore, the rise time of these pulses has been chosen taking into account the constraints given by both the bandwidth of the microwave multiplexing read out with a flux ramp demodulation and the bandwidth of the ADC boards currently available for ROACH2. Among the different rejection techniques evaluated, the Wiener Filter technique, a digital filter to gain time resolution, has shown an excellent pile-up rejection efficiency. The obtained time resolution closely matches the baseline specifications of the HOLMES experiment. We report here a description of our simulation code and a comparison of the different rejection techniques.

  2. In situ Gas Measurements in Five Experimental Waste Rock Piles, Antamina Mine, Peru

    NASA Astrophysics Data System (ADS)

    Singurindy, O.; Blackmore, S. R.; Wild, A.; Mayer, K. U.; Beckie, R. D.; Smith, L.

    2009-12-01

    At the Antamina mine (Peru), a skarn deposit consisting of a quartz-monzonite porphyry hosted in limestone is mined for copper, zinc, lead, and molybdenum. Five (5) experimental waste rock piles were constructed at Antamina and instrumented to evaluate processes controlling metal release under neutral-pH drainage conditions. The piles were built over a 3-year period and each contains approximately 25,000 tonnes of waste rock classified as ‘slightly reactive’ (Pile 1 -2007), ‘reactive’ (Pile 2 and 3 - 2008), or a combination of rock of variable reactivity (Pile 4 and 5 - 2009). All waste rock, reactive to non-reactive, contains variable amounts of sulphide and carbonate minerals. Oxidation of sulphide minerals consumes O2 and generates low-pH conditions, which promotes carbonate dissolution and elevates CO2 concentrations. Sampling of the piles’ 64 in situ gas lines, using a portable gas analyzing system, revealed numerous CO2-enriched and O2-depleted zones. Piles constructed of the most reactive and fine-grained rock (Pile 2 and 3) show the highest CO¬2 concentrations (≥ 20,000 ppm), with Piles 1, 4 and 5 showing lower maximum concentrations of 1,600 ppm, 1,100 ppm, 2,900 ppm, respectively. The highest CO2 concentrations are located in the interior and near the bottom of the piles. Of the gas lines sampled from Pile 2 and 3, 88% and 95%, respectively are CO2-enriched (defined as > 2 x ambient values). The younger and less reactive piles (Pile 4 and 5) show CO2-enriched values in 3% and 17% of gas lines measured. The exothermic reaction of sulphide oxidation is also monitored by 12 in situ thermistors. Pile 2 and 3 temperatures are the highest at 9 - 10 oC. These temperatures are significantly warmer than ambient conditions (i.e., ~ 6 oC, June average) and correlate well with pockets of high CO2 concentrations. The gradational decline of CO2 concentrations with depth supports the notion that gas transport is dominated by vertical movement, while

  3. Mapping of noise impact provoked by the execution of foundation piles at high rise building sites.

    PubMed

    de Araújo, Adolpho Guido; Gusmão, Alexandre Duarte; Rabbani, Emilia Rahnemay Kohman; Fucale, Stela Paulino

    2012-01-01

    The objective of this work is to map, in a limited area inside and outside of the worksite, the environmental impact generated by sound pollution coming from the driving of foundation piles for high rise buildings, as well as to observe and check if the noise levels produced by the emitting source are tolerable in the urban environment. The methodology of the work includes a survey of technical references about the subject; measurement of noises surrounding the worksite during the foundation phase for four distinct buildings, with different types of piles: prefabricated piles, continuous helical displacement piles , traditional compaction piles and Terra Probe compaction piles. A grid of points was built due to the time of driving and after that the measurements of environmental noises were performed emitted by the execution of each type of pile using a sound level meter. The interpretation of the measurements and their impacts on the neighborhood of the building were performed using the computational tool Suffer for creating noise level contours. The X and Y axes of the grid represent the distances in meters of the area studied and the Z axis represents the noise measured in dB. The contours developed represent the mapping of the noise at the worksites and their surroundings. The mapping of the urban impact of noise, the measurement of its dimensions, and the examination of its propagation around the building are important subsides to adequate individual and collective protection procedures. Seventy one points were measured at four building sites with different types of piles, and the results showed that at only three points was the noise within the limits of the Municipal Law of Recife of 70 dB, which proves the relevance of the research. Finally, the comparative analysis between the four types of piles shows that the continuous helical displacement pile emits the lowest noise level among the four pile types studied.

  4. Mapping of noise impact provoked by the execution of foundation piles at high rise building sites.

    PubMed

    de Araújo, Adolpho Guido; Gusmão, Alexandre Duarte; Rabbani, Emilia Rahnemay Kohman; Fucale, Stela Paulino

    2012-01-01

    The objective of this work is to map, in a limited area inside and outside of the worksite, the environmental impact generated by sound pollution coming from the driving of foundation piles for high rise buildings, as well as to observe and check if the noise levels produced by the emitting source are tolerable in the urban environment. The methodology of the work includes a survey of technical references about the subject; measurement of noises surrounding the worksite during the foundation phase for four distinct buildings, with different types of piles: prefabricated piles, continuous helical displacement piles , traditional compaction piles and Terra Probe compaction piles. A grid of points was built due to the time of driving and after that the measurements of environmental noises were performed emitted by the execution of each type of pile using a sound level meter. The interpretation of the measurements and their impacts on the neighborhood of the building were performed using the computational tool Suffer for creating noise level contours. The X and Y axes of the grid represent the distances in meters of the area studied and the Z axis represents the noise measured in dB. The contours developed represent the mapping of the noise at the worksites and their surroundings. The mapping of the urban impact of noise, the measurement of its dimensions, and the examination of its propagation around the building are important subsides to adequate individual and collective protection procedures. Seventy one points were measured at four building sites with different types of piles, and the results showed that at only three points was the noise within the limits of the Municipal Law of Recife of 70 dB, which proves the relevance of the research. Finally, the comparative analysis between the four types of piles shows that the continuous helical displacement pile emits the lowest noise level among the four pile types studied. PMID:22317218

  5. Method and apparatus for analog pulse pile-up rejection

    SciTech Connect

    De Geronimo, Gianluigi

    2014-11-18

    A method and apparatus for pulse pile-up rejection are disclosed. The apparatus comprises a delay value application constituent configured to receive a threshold-crossing time value, and provide an adjustable value according to a delay value and the threshold-crossing time value; and a comparison constituent configured to receive a peak-occurrence time value and the adjustable value, compare the peak-occurrence time value with the adjustable value, indicate pulse acceptance if the peak-occurrence time value is less than or equal to the adjustable value, and indicate pulse rejection if the peak-occurrence time value is greater than the adjustable value.

  6. Method and apparatus for analog pulse pile-up rejection

    SciTech Connect

    De Geronimo, Gianluigi

    2013-12-31

    A method and apparatus for pulse pile-up rejection are disclosed. The apparatus comprises a delay value application constituent configured to receive a threshold-crossing time value, and provide an adjustable value according to a delay value and the threshold-crossing time value; and a comparison constituent configured to receive a peak-occurrence time value and the adjustable value, compare the peak-occurrence time value with the adjustable value, indicate pulse acceptance if the peak-occurrence time value is less than or equal to the adjustable value, and indicate pulse rejection if the peak-occurrence time value is greater than the adjustable value.

  7. Drilling template acurately leveled with pile-supported system

    SciTech Connect

    Not Available

    1992-12-21

    This paper reports on a drilling template for BP Exploration Inc.'s Pompano field set to within 0.015[degrees] of level in Viosca Knoll Block 989 offshore Louisiana. The 280-slot, 285-ton template was installed in 1,290 ft of water. The typical tolerance for a template setting is [plus minus]0.25[degrees] of level. This accuracy ensures that the docking piles will function properly when the jacket is installed and prevents problems with misalignment of drilling and tieback equipment.

  8. 9. PIER NO. 4, REVISED GENERAL LAYOUT OF PILING AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. PIER NO. 4, REVISED GENERAL LAYOUT OF PILING AND FRAMING. United Engineering Company Ltd., Alameda Shipyard, Ship Repair Facilities. John Hudspeth, Architect, at foot of Main Street, Alameda, Calif. Sheet no. S3 of 5 sheets, Plan no. 10,037. Various scales. August 26, 1942, last revised 4/15/43. U.S. Navy, Bureau of Yards & Docks, Contract no. bs 76. Approved for construction September 17, 1943. blueprint - United Engineering Company Shipyard, Pier 4, 2900 Main Street, Alameda, Alameda County, CA

  9. Des Vents et des Jets Astrophysiques

    NASA Astrophysics Data System (ADS)

    Sauty, C.

    well expected result from the theory. Although, collimation may be conical, paraboloidal or cylindrical (Part 4), cylindrical collimation is the more likely to occur. The shape of outflows may then be used as a tool to predict physical conditions on the flows or on their source. L'éjection continue de plasma autour d'objets massifs est un phénomène largement répandu en astrophysique, que ce soit sous la forme du vent solaire, de vents stellaires, de jets d'étoiles en formation, de jets stellaires autour d'objets compacts ou de jets extra-galactiques. Cette zoologie diversifiée fait pourtant l'objet d'un commun effort de modélisation. Le but de cette revue est d'abord de présenter qualitativement le développement, depuis leur origine, des diverses théories de vents (Partie 1) et l'inter disciplinarité dans ce domaine. Il s'agit d'une énumération, plus ou moins exhaustive, des idées proposées pour expliquer l'accélération et la morphologie des vents et des jets, accompagnée d'une présentation sommaire des aspects observationnels. Cette partie s'abstient de tout aspect faisant appel au formalisme mathématique. Ces écoulements peuvent être décrits, au moins partiellement, en résolvant les équations magnétohydrodynamiques, axisymétriques et stationnaires. Ce formalisme, à la base de la plupart des théories, est exposé dans la Partie 2. Il permet d'introduire quantitativement les intégrales premières qu'un tel système possède. Ces dernières sont amenées à jouer un rôle important dans la compréhension des phénomènes d'accélération ou de collimation, en particulier le taux de perte de masse, le taux de perte de moment angulaire ou l'énergie du rotateur magnétique. La difficulté de modélisation réside dans l'existence de points critiques, propres aux équations non linéaires, qu'il faut franchir. La nature physique et la localisation de ces points critiques fait l'objet d'un débat important car ils sont la clef de voute de la r

  10. Injectabilite des coulis de ciment dans des milieux fissures

    NASA Astrophysics Data System (ADS)

    Mnif, Thameur

    Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

  11. Static Buckling Model Tests and Elasto-plastic Finite Element Analysis of a Pile in Layers with Various Thicknesses

    NASA Astrophysics Data System (ADS)

    Okajima, Kenji; Imai, Junichi; Tanaka, Tadatsugu; Iida, Toshiaki

    Damage to piles in the liquefied ground is frequently reported. Buckling by the excess vertical load could be one of the causes of the pile damage, as well as the lateral flow of the ground and the lateral load at the pile head. The buckling mechanism is described as a complicated interaction between the pile deformation by the vertical load and the earth pressure change cased by the pile deformation. In this study, series of static buckling model tests of a pile were carried out in dried sand ground with various thickness of the layer. Finite element analysis was applied to the test results to verify the effectiveness of the elasto-plastic finite element analysis combining the implicit-explicit mixed type dynamic relaxation method with the return mapping method to the pile buckling problems. The test results and the analysis indicated the possibility that the buckling load of a pile decreases greatly where the thickness of the layer increases.

  12. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof. 303.24 Section 303.24 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile...

  13. In-situ grouting of uranium-mill-tailings piles: an assessment

    SciTech Connect

    Tamura, T.; Boegly, W.J. Jr.

    1983-05-01

    Passage in 1978 of the Uranium Mill Tailings Radiation Control Act (UMTRCA) initiated a program of remedial action for 22 existing mill tailings piles generated in the period 1940 to 1970 as part of the nation's defense and nuclear power programs. The presence of these piles poses potential health and environmental contamination concerns. Possible remedial actions proposed include multilayer covers over the piles to reduce water infiltration, reduce radon gas releases, and reduce airborne transport of tailings fines. In addition, suggested remedial actions include (1) the use of liners to prevent groundwater contamination by leachates from the piles and (2) chemical stabilization of the tailings to retain the radioactive and nonradioactive sources of contamination. Lining of the piles would normally be applicable only to piles that are to be moved from their present location such that the liner could be placed between the tailings and the groundwater. However, by using civil engineering techniques developed for grouting rocks and soils for strength and water control, it may be possible to produce an in situ liner for piles that are not to be relocated. The Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project Office requested that ORNL assess the potential application of grouting as a remedial action. This report examines the types of grouts, the equipment available, and the costs, and assesses the possibility of applying grouting technology as a remedial action alternative for uranium mill tailings piles.

  14. Influences of Family Management and Spousal Perceptions on Stressor Pile-up.

    ERIC Educational Resources Information Center

    Imig, David R.; Imig, Gail L.

    1986-01-01

    Describes the contingent influence of family managerial efficacy and related spousal perceptions on the relationship between stressor pile-up and family cohesion. Perceived loss of managerial efficacy in conjunction with discrepant spousal perceptions of such change substantially increased the family's vulnerability to stressor pile-up. A…

  15. 40 CFR 270.18 - Specific part B information requirements for waste piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements for waste piles. 270.18 Section 270.18 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Permit Application § 270.18 Specific part B information requirements for waste piles. Except as otherwise provided in § 264.1, owners and operators of facilities that store or treat hazardous waste in waste...

  16. Pile mixing increases greenhouse gas emissions during composting of dairy manure.

    PubMed

    Ahn, H K; Mulbry, W; White, J W; Kondrad, S L

    2011-02-01

    The effect of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. GHG emissions from compost piles that were mixed four times during the 80 day trial were approximately 20% higher than emissions from unmixed (static) piles. For both treatments, carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) accounted for 75-80%, 18-21%, and 2-4% of GHG emissions, respectively. Seventy percent of CO(2) emissions and 95% of CH(4) emissions from all piles occurred within first 23 days. By contrast, 80-95% of N(2)O emissions occurred after this period. Mixed and static piles released 2 and 1.6 kg GHG (CO(2)-Eq.) for each kg of degraded volatile solids (VS), respectively. Our results suggest that to minimize GHG emissions, farmers should store manure in undisturbed piles or delay the first mixing of compost piles for approximately 4 weeks.

  17. 30 CFR 780.25 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... specific design parameters and construction methods. (d) Coal mine waste impoundments and refuse piles. If you, the permit applicant, propose to place coal mine waste in a refuse pile or impoundment, or if...

  18. 40 CFR 411.30 - Applicability; description of the materials storage piles runoff subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... runoff of rainfall which derives from the storage of materials including raw materials, intermediate... materials storage piles runoff subcategory. 411.30 Section 411.30 Protection of Environment ENVIRONMENTAL... Materials Storage Piles Runoff Subcategory § 411.30 Applicability; description of the materials...

  19. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... Nail or otherwise fasten to the top of the marker two pieces of string or cord of sufficient length and... the pile sufficiently to allow the strings to move easily around the pile when they are pulled tight...) of the location for each sample. (A) Tie to a stake or otherwise fasten one of the strings at...

  20. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Nail or otherwise fasten to the top of the marker two pieces of string or cord of sufficient length and... the pile sufficiently to allow the strings to move easily around the pile when they are pulled tight...) of the location for each sample. (A) Tie to a stake or otherwise fasten one of the strings at...

  1. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... Nail or otherwise fasten to the top of the marker two pieces of string or cord of sufficient length and... the pile sufficiently to allow the strings to move easily around the pile when they are pulled tight...) of the location for each sample. (A) Tie to a stake or otherwise fasten one of the strings at...

  2. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Nail or otherwise fasten to the top of the marker two pieces of string or cord of sufficient length and... the pile sufficiently to allow the strings to move easily around the pile when they are pulled tight...) of the location for each sample. (A) Tie to a stake or otherwise fasten one of the strings at...

  3. In-pile and out-of-pile testing of a molybdenum-uranium dioxide cermet fueled themionic diode

    NASA Technical Reports Server (NTRS)

    Diianni, D. C.

    1972-01-01

    The behavior of Mo-UO2 cermet fuel in a diode for thermionic reactor application was studied. The diode had a Mo-0.5 Ti emitter and niobium collector. Output power ranged from 1.4 to 2.8 W/cm squared at emitter and collector temperatures of 1500 deg and 540 C. Thermionic performance was stable within the limits of the instrumentation sensitivity. Through 1000 hours of in-pile operation the emitter was dimensionally stable. However, some fission gases (15 percent) leaked through an inner clad imperfection that occurred during fuel fabrication.

  4. Unmanned Aerial Vehicle Use for Wood Chips Pile Volume Estimation

    NASA Astrophysics Data System (ADS)

    Mokroš, M.; Tabačák, M.; Lieskovský, M.; Fabrika, M.

    2016-06-01

    The rapid development of unmanned aerial vehicles is a challenge for applied research. Many technologies are developed and then researcher are looking up for their application in different sectors. Therefore, we decided to verify the use of the unmanned aerial vehicle for wood chips pile monitoring. We compared the use of GNSS device and unmanned aerial vehicle for volume estimation of four wood chips piles. We used DJI Phantom 3 Professional with the built-in camera and GNSS device (geoexplorer 6000). We used Agisoft photoscan for processing photos and ArcGIS for processing points. Volumes calculated from pictures were not statistically significantly different from amounts calculated from GNSS data and high correlation between them was found (p = 0.9993). We conclude that the use of unmanned aerial vehicle instead of the GNSS device does not lead to significantly different results. Tthe data collection consumed from almost 12 to 20 times less time with the use of UAV. Additionally, UAV provides documentation trough orthomosaic.

  5. Acoustic emission intensity analysis of corrosion in prestressed concrete piles

    NASA Astrophysics Data System (ADS)

    Vélez, William; Matta, Fabio; Ziehl, Paul

    2014-02-01

    Corrosion of steel strands in prestressed concrete (PC) bridges may lead to substantial damage or collapse well before the end of the design life. Acoustic Emission (AE) is a suitable nondestructive technique to detect and locate corrosion in reinforced and prestressed concrete, which is key to prioritize inspection and maintenance. An effective tool to analyze damage-related AE data is intensity analysis (IA), which is based on two data trends, namely Severity (average signal strength of high amplitude hits) and Historic Index (ratio of the average signal strength of the most recent hits to the average of all hits). IA criteria for corrosion assessment in PC were recently proposed based on empirical evidence from accelerated corrosion tests. In this paper, AE data from prestressed and non-prestressed concrete pile specimens exposed to salt water wet-dry cycling for over 600 days are used to analyze the relation between Severity and Historic Index and actual corrosion. Evidence of corrosion is gained from the inspection of decommissioned specimens. The selection of suitable J and K parameters for IA is discussed, and an IA chart with updated corrosion criteria for PC piles is presented.

  6. Evaluation of Candidate In-Pile Thermal Conductivity Techniques

    SciTech Connect

    B. Fox; H. Ban; J. Daw; K. Condie; D. Knudson; J. Rempe

    2009-05-01

    Thermophysical properties of materials must be known for proper design, test, and application of new fuels and structural properties in nuclear reactors. In the case of nuclear fuels during irradiation, the physical structure and chemical composition change as a function of time and position within the rod. Typically, thermal conductivity changes, as well as other thermophysical properties being evaluated during irradiation in a materials and test reactor, are measured out-of-pile in “hot-cells.” Repeatedly removing samples from a test reactor to make out-of-pile measurements is expensive, has the potential to disturb phenomena of interest, and only provide understanding of the sample's end state at the time each measurement is made. There are also limited thermophysical property data for advanced fuels. Such data are needed for the development of next generation reactors and advanced fuels for existing nuclear plants. Having the capacity to effectively and quickly characterize fuels and material properties during irradiation has the potential to improve the fidelity of nuclear fuel data and reduce irradiation testing costs.

  7. Lateral loading on piles due to slope instability

    SciTech Connect

    Lupini, J.F.; Chacin, M.E.; Furiol, A.; Troconis, C.M.; Vargas, F.

    1995-12-01

    This paper presents the Caripito Oil Loading Terminal case history for which very flat slope instability was responsible for the failure and structural collapse of seven mooring and/or breasting dolphins, plus the collapse of all of the intermediate supports of catwalk bridges that provide access to the dolphins, from or to the loading platforms. These supports collapsed before the dolphins did as, in the whole, they were much weaker to support lateral thrusts, even though they were strengthened with additional piles, on several occasions. When movement of the dolphins first became apparent, a monitoring program was designed to measure the displacement of the pile caps. The primary cause for failure was the very weak nature of the subsoil, but the triggering mechanism was the need to dredge the bottom, further than previously in the past, because of the new recent condition of siltation and sedimentation and to accommodate larger tankers with larger draughts. Although most of the dolphins failed in a three year period, the trestles and the loading platforms have not shown, so far, significant signs of distress. This paper deals with the site assessment program, with what caused the failures, how the collapse occurred and the conclusions, that were drawn during the study.

  8. A numerical study of the effect of groundwater on spiral coil energy piles

    NASA Astrophysics Data System (ADS)

    Kim, Seong-Kyun; Lee, Youngmin

    2016-04-01

    Numerical simulations were performed to investigate effects of groundwater on the thermal performance of the geothermal energy pile. Energy piles, a part of the closed-loop geothermal heat pump systems, are used to exchange heat between the ground and the heat pump. A heat-carrying fluid circulates the ground through a coiled pipe installed in pile foundations. The COMSOL multiphysics was used as a simulator, which can solve the equations for the temperature and fluid flow in the pipe system, as well as those in the ground. Water temperatures at the pipe outlet after 90-day injection of warm water (30℃) were calculated from following cases: (1) one energy pile installed at the fully saturated medium with regional groundwater flow (100 m/year), (2) one energy pile installed at the partially saturated medium (water table is located 13.5 m below the ground surface) with regional groundwater flow (1,000 m/year), (3) one energy pile installed at the fully saturated medium with no regional groundwater flow, (4) one energy pile installed at the partially saturated medium with no regional groundwater flow, (5), (6), (7) four energy piles (distance between energy piles is 10, 5 ,2 m) installed at the fully saturated medium with regional groundwater flow, and (8), (9), (10) four energy piles installed at the partially saturated medium with regional groundwater flow. The outlet temperature of each case is (1) 28.11℃, (2) 28.84℃, (3) 28.97℃, (4) 29.09℃, (5) 28.19℃ (mean value), (6) 28.24℃ (mean value), (7) 28.33℃ (mean value), (8) 28.84℃ (mean value), (9) 28.90℃ (mean value), and (10) 29.10℃ (mean value), respectively. The thermal power ratio of the energy pile of each case (standard case is case 1) is (1) 0%, (2) -46%, (3) -39%, (4) -52%, (5) -4%, (6) -7%, (7) -12%, (8) -39%, (9) -42%, and (10) -53%, respectively. Numerical results show that the performance of the energy pile installed at the fully saturated medium with regional groundwater flow (case 1

  9. Comparative analysis of seismic response characteristics of pile-soil-structure interaction system

    NASA Astrophysics Data System (ADS)

    Kong, Desen; Luan, Maotian; Wang, Weiming

    2006-01-01

    The study on the earthquake-resistant performance of a pile-soil-structure interaction system is a relatively complicated and primarily important issue in civil engineering practice. In this paper, a computational model and computation procedures for pile-supported structures, which can duly consider the pile-soil interaction effect, are established by the finite element method. Numerical implementation is made in the time domain. A simplified approximation for the seismic response analysis of pile-soil-structure systems is briefly presented. Then a comparative study is performed for an engineering example with numerical results computed respectively by the finite element method and the simplified method. Through comparative analysis, it is shown that the results obtained by the simplified method well agree with those achieved by the finite element method. The numerical results and findings will offer instructive guidelines for earthquake-resistant analysis and design of pile-supported structures.

  10. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    NASA Astrophysics Data System (ADS)

    Testa, M.

    2016-07-01

    The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are presented here. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  11. Dynamic interaction between the soil and an anchored sheet pile during seismic excitation

    NASA Astrophysics Data System (ADS)

    Degrande, G.; Praet, E.; van Zegbroeck, B.; van Marcke, P.

    2002-05-01

    A subdomain approach for dynamic soil-structure interaction is proposed for the linear elastic seismic analysis of an anchored sheet pile, retaining a horizontally layered soil on rigid bedrock. A hybrid solution technique is used, employing a finite element formulation for the generalized sheet pile, a thin layer formulation for the soil and a direct stiffness formulation for the tieback; the displacement vectors of the sheet pile and the soil are decomposed, using the eigenmodes of the sheet pile and the propagating or decaying modes in the soil. The discretization can be limited to the interface(s), where pointwise continuity of the displacements is enforced, whereas a weak variational formulation is used for the stress equilibrium. The solution technique is illustrated by means of a numerical example, where the harmonic response of a flexible anchored sheet pile is considered and compared to the case where no tieback is present.

  12. Residency of Reef Fish During Pile Driving Within a Shallow Pierside Environment.

    PubMed

    Iafrate, Joseph D; Watwood, Stephanie L; Reyier, Eric A; Gilchrest, Matthew; Crocker, Steven E

    2016-01-01

    The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of construction occurring in coastal habitats throughout the world. In this study, we used acoustic telemetry to assess the movement and survival of free-ranging reef fish in Port Canaveral, FL, in response to 35 days of pile driving at an existing wharf complex. The site fidelity and behavior of 15 sheepshead (Archosargus probatocephalus) and 10 gray snapper (Lutjanus griseus) were determined before, during, and after pile driving. No obvious signs of mortality or injury to tagged fish were evident from the data. There was a significant decline in the residency index for mangrove snapper at the construction wharf after pile driving compared with the baseline, although this may be influenced by natural movements of this species in the study area rather than a direct response to pile driving.

  13. Evaluation of sleeve-pile set models used in docking jacket operation simulation

    SciTech Connect

    Cyranka, C.; Mourelle, M.M.; Ebecken, N.F.F.

    1995-12-31

    This work deals with the behavior of sleeve-pile set models used in the simulation of docking jacket operations. The adopted strategy involves the comparison of three-dimensional dynamic analysis with complete models, where docking pile and marine soil are considered. This dynamic analysis is performed in the time domain, including all the environmental loads and ship motions, using a substructure technique. The main discussion is focused in appropriate modeling the sleeve-pile set. Two propositions were examined: in the first one, the nonlinear docking spring takes into account the sleeve, pile and nonlinear soil contributions; in the second, the docking sleeve characteristics were added to the jacket model. To reach the objectives a real docking operation case was selected. A typical Campos Basin jacket was modeled with fine discretization of all details to access precisely the sleeve-pile set interaction. The obtained results can establish practical conclusions to docking jacket analysis.

  14. Chemical and thermal variations in seeps discharged from a burning coal refuse pile

    NASA Astrophysics Data System (ADS)

    Lopez, D. L.; Doe, C. F.; Stuart, B. J.; Stoertz, M. W.

    2002-12-01

    Acid mine drainage generated by coal refuse piles is affecting the Moxahala watershed in Southeastern Ohio. The major contributor of acidity to this watershed is the Misco refuse pile. This pile was formed during the exploitation of the Misco Mine in Perry County, Ohio, in the early 1950's. In addition to the generation of acid mine drainage, the Misco Pile is burning. There is an impounded pond on the southwest end of the west gob pile, which was created when the valley was filled with refuse. The water from this pond flows into and throughout the gob pile and discharges on the northeast end into Bennet Run. At an elevation close to the elevation of the pond, two seeps are discharged. Temperature, specific conductivity, and pH was monitored in these seeps and correlated to rainfall. A lack of response of water temperature to small rainfall events was observed. This behavior suggest channeling of water inside the pile from the source pond to the main seep, and probably evaporation effects. In comparison, during high rainfall events, transfer of heat from the burning spots to the infiltrating water occurred and an increase in seep temperature was observed. A decrease in conductivity and an increase in pH was observed during the studied period as a dilution effect produced by an increased water storage within the pond and pile. Diurnal effects were stronger in the smaller seep, probably due to lower water velocities and greater residence time at the air-pile interface. From the location of the burning spots and seeps, a water velocity of 1 to 5 feet/s (0.3 to 1.7 m/s) was estimated. The pile can be viewed as a dual-porosity system of continuous conduits and matrix porosity. Only flow with sufficient head can penetrate and transfer heat from the hot areas in the matrix.

  15. A three-dimensional vibroacoustic model for the prediction of underwater noise from offshore pile driving

    NASA Astrophysics Data System (ADS)

    Tsouvalas, A.; Metrikine, A. V.

    2014-04-01

    Steel monopiles are nowadays widely used as foundations for a large number of offshore structures. The installation procedure commonly involves a pile driving process which can last up to several hours depending upon pile dimensions, soil conditions and input energy of the hydraulic hammer. In impact pile driving, a hydraulic hammer delivers a series of hammer blows at the head of the pile that drive the pile into the sediment. Each hammer strike results in pile vibrations that emit strong impulsive sounds into the water column which can be harmful for the marine ecosystem. With today's increasing concern regarding the environmental impact of such operations, engineering tools which will be able to provide reliable predictions of the underwater noise levels are required. In this study, a linear semi-analytical formulation of the coupled vibroacoustics of a complete pile-water-soil interaction model is addressed. The pile is described by a high order thin shell theory whereas both water and soil are modelled as three-dimensional continua. Results obtained with the developed model indicate that the near-field response in the water column consists mainly of pressure conical waves generated by the supersonic compressional waves in the pile excited by the impact hammer. The soil response is dominated by shear waves with almost vertical polarization. The Scholte waves are also generated at the water-seabed interface which can produce pressure fluctuations in the water column that are particularly significant close to the sea floor. The effects of soil elasticity and pile size are thoroughly investigated and their influence on the generated pressure levels is highlighted. The results are also compared with those ones of a similar model in which the soil is treated as an equivalent acoustic fluid. It is shown that the latter approximation can yield inaccurate results at low frequencies especially for harder soil sediments.

  16. Response evaluation for horizontally loaded fixed-head pile groups using 3-D non-linear analysis

    NASA Astrophysics Data System (ADS)

    Comodromos, Emilios M.; Pitilakis, Kyriazis D.

    2005-05-01

    The response of laterally loaded pile foundations may be significantly important in the design of structures for such loads. A static horizontal pile load test is able to provide a load-deflection curve for a single free-head pile, which significantly differs from that of a free- or fixed-head pile group, depending on the particular group configuration. The aim of this paper is to evaluate the influence of the interaction between the piles of a group fixed in a rigid pile cap on both the lateral load capacity and the stiffness of the group. For this purpose, a parametric three-dimensional non-linear numerical analysis was carried out for different arrangements of pile groups. The response of the pile groups is compared to that of the single pile. The influence of the number of piles, the spacing and the deflection level to the group response is discussed. Furthermore, the contribution of the piles constituting the group to the total group resistance is examined. Finally, a relationship is proposed allowing a reasonable prediction of the response of fixed-head pile groups at least for similar soil profile conditions.

  17. Constraining the Interior Geophysics of Rubble Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Scheeres, D. J.; Jacobson, S.; McMahon, J.; Hirabayashi, M.

    2013-12-01

    The internal geophysics of small rubble pile asteroids are largely unknown, and standard geophysical theories are not well matched to the extreme environment these bodies exist in. Interior pressures within rapidly spinning rubble piles are predicted to be as small as a few Pascals, a regime in which small non-gravitational forces not considered for larger bodies may become important. Previous research has suggested that the standard geophysical models for internal energy dissipation in this regime require modification (Goldreich and Sari, ApJ 2009), adding additional uncertainty in the geophysics. We report on new theoretical and observational results that suggest a direct way in which fundamental geophysical parameters of small rubble pile asteroids can be constrained. Specifically, we will discuss how the ratio Q/k, tidal dissipation number over tidal Love number, can be inferred and more strictly constrained for primaries in small binary asteroid systems where the secondary is spin-synchronized and the primary is super-synchronous, the most common class of small asteroid binary systems. Jacobson & Scheeres (ApJ 2011) proposed that many of these binary asteroid systems may be in an equilibrium state where contractive Binary YORP forces balance against expansive tidal torques due to tidal distortion of the primary body. The predicted equilibrium semi-major axes for such binary asteroid systems (based on presumed values for the Binary YORP force and Q/k values) has been seen to be consistent with the observed sizes of many of these systems (see figure). Recently, it has also been reported that the spacecraft-accessible binary asteroid 1996 FG3 is in such an equilibrium state (Scheirich et al., Binaries Workshop 2013). The combined detection of such an equilibrium coupled with their theoretical model makes it feasible to sharply constrain the Q/k parameter for the primary asteroid in the 1996 FG3 system and extrapolate its functional form to other such systems. We

  18. Grundlagen des Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mayer, Jörg; Blum, Janaki; Wintermantel, Erich

    Die Organtransplantation stellt eine verbreitete Therapie dar, um bei krankheitsoder unfallbedingter Schädigung eines Organs die Gesamtheit seiner Funktionen wieder herzustellen, indem es durch ein Spenderorgan ersetzt wird. Organtransplantationen werden für die Leber, die Niere, die Lunge, das Herz oder bei schweren grossflächigen Verbrennungen der Haut vorgenommen. Der grosse apparative, personelle und logistische Aufwand und die Risiken der Transplantationschirurgie (Abstossungsreaktionen) sowie die mangelnde Verfügbarkeit von immunologisch kompatiblen Spenderorganen führen jedoch dazu, dass der Bedarf an Organtransplantaten nur zu einem sehr geringen Teil gedeckt werden kann. Sind Spenderorgane nicht verfügbar, können in einzelnen Fällen lebenswichtige Teilfunktionen, wie beispielsweise die Filtrationsfunktion der Niere durch die Blutreinigung mittels Dialyse ersetzt oder, bei mangelnder Funktion der Bauchspeicheldrüse (Diabetes), durch die Verabreichung von Insulin ein normaler Zustand des Gesamtorganismus auch über Jahre hinweg erhalten werden. Bei der notwendigen lebenslangen Anwendung apparativer oder medikamentöser Therapie können für den Patienten jedoch häufig schwerwiegende, möglicherweise lebensverkürzende Nebenwirkungen entstehen. Daher werden in der Forschung Alternativen gesucht, um die Funktionen des ausgefallenen Organs durch die Implantation von Zellen oder in vitro gezüchteten Geweben möglichst umfassend wieder herzustellen. Dies erfordert biologisch aktive Implantate, welche die für den Stoffwechsel des Organs wichtigen Zellen enthalten und einen organtypischen Stoffwechsel entfalten.

  19. Large deformation finite element analysis of undrained pile installation

    NASA Astrophysics Data System (ADS)

    Konkol, Jakub; Bałachowski, Lech

    2016-03-01

    In this paper, a numerical undrained analysis of pile jacking into the subsoil using Abaqus software suit has been presented. Two different approaches, including traditional Finite Element Method (FEM) and Arbitrary Lagrangian-Eulerian (ALE) formulation, were tested. In the first method, the soil was modelled as a two-phase medium and effective stress analysis was performed. In the second one (ALE), a single-phase medium was assumed and total stress analysis was carried out. The fitting between effective stress parameters and total stress parameters has been presented and both solutions have been compared. The results, discussion and verification of numerical analyzes have been introduced. Possible applications and limitations of large deformation modelling techniques have been explained.

  20. Prehistoric Packrats Piled Up Clues to Climate Change

    USGS Publications Warehouse

    Cole, Kenneth L.

    2008-01-01

    Scientists from the U.S. Geological Survey and Northern Arizona University studying climate change in the Southwestern United States are getting a helping hand?or would that be paw??from prehistoric packrats. By hoarding parts of animals and plants, including seeds and leaves, in garbage piles or ?middens,? these bushy-tailed rodents preserved crucial ecological and environmental information about the past. From these middens, scientists are able to reconstruct plant communities and natural systems from as long ago as 50,000 years. The contents of middens allow scientists to understand how ecosystems responded to rapid, large-scale climate changes of the past. The insights gained from midden research could offer clues to future changes driven by rapid climate shifts.

  1. Simulating pile load-settlement behavior from CPT data using intelligent computing

    NASA Astrophysics Data System (ADS)

    Alkroosh, I.; Nikraz, H.

    2011-09-01

    Analysis of pile load-settlement behavior is a complex problem due to the participation of many factors involved. This paper presents a new procedure based on artificial neural networks (ANNs) for simulating the load-settlement behavior of pile foundations embedded in sand and mixed soils (subjected to axial loads). Three ANN models have been developed, a model for bored piles and two other models for driven piles (a model for each of concrete and steel piles). The data used for development of the ANN models is collected from the literature and comprise a series of in-situ piles load tests as well as cone penetration test (CPT) results. The data of each model is divided into two subsets: Training set for model calibration and independent validation set for model verification. Predictions from the ANN models are compared with the results of experimental data and with predictions of number of currently adopted load-transfer methods. Statistical analysis is used to verify the performance of the models. The results indicate that the ANN model performs very well and able to predict the pile load-settlement behaviour accurately.

  2. Distributed fiber optic sensors for monitoring reinforced concrete piles using Brillouin scattering

    NASA Astrophysics Data System (ADS)

    de Battista, N.; Kechavarzi, C.; Soga, K.

    2016-05-01

    In this paper we report on advances made in the installation and use of distributed fiber optic sensors to monitor reinforced concrete piles subjected to static load tests. Eight concrete test piles, at three construction sites in London, have recently been instrumented with embedded DFOS. The Brillouin optical time domain reflectometry (BOTDR) technique was used to measure the changes in internal strain and temperature of the piles, during concrete curing and during load testing. These data were used to assess the quality of the pile and derive the load capacity parameters to be used in the foundation design of tall buildings which are to be erected on these sites. The measurements obtained from the DFOS system agreed well with the measurements taken simultaneously using conventional point sensors embedded in the piles. Whereas the conventional sensors only provided measurements at a small number of locations within the piles, the DFOS system made it possible to record the complete strain / temperature profiles along the length of the piles.

  3. Hearing thresholds of two harbor seals (Phoca vitulina) for playbacks of multiple pile driving strike sounds.

    PubMed

    Kastelein, Ronald A; Hoek, Lean; Gransier, Robin; Jennings, Nancy

    2013-09-01

    Pile driving, which creates high amplitude sounds with potentially negative impacts on the marine environment, is used to attach wind turbines to the sea bed. To quantify the distance at which pile driving sounds can be detected by harbor seals, unmasked hearing thresholds were obtained for series of five pile driving sounds recorded at 100 and 800 m from a pile driving location. The played back spectra resembled the spectra of sounds recorded under certain conditions 10-50 km from an offshore pile driving site. The lower the received level, the later within the series of sounds the harbor seals responded. The mean 50% detection threshold sound exposure levels for any sound in the series were: 40 (seal 01, 100 m), 39 (seal 01, 800 m), 43 (seal 02, 100 m), and 43 (seal 02, 800 m) dB re 1 μPa(2)s (add 9 dB for sound pressure level, dB re 1 μPa). The mean 50% detection thresholds based on detection of only the first sound of the series were ca. 5 dB higher. Detection at sea depends on the actual propagation conditions and on the degree of masking of the sounds by ambient noise, but the present study suggests that pile driving sounds are audible to harbor seals up to hundreds of kilometers from pile driving sites. PMID:23967961

  4. Structural Modeling Of Rubble Piles In Two And Three Dimensions

    NASA Astrophysics Data System (ADS)

    Korycansky, Donald

    2012-10-01

    One of the puzzles about the structure of asteroids and other small bodies of the solar system is amount void space that is apparently present, from measurements of their bulk densities as compared to the mineral grain densities of their surfaces. In many cases, void fractions of 40% or more are inferred. The question arises as to whether this large void fraction is the result of large-scale internal structure ("macroporosity") or small-scale grain-density effects ("microporosity"). In this work I present results from modeling rubble piles. In particular, rubble piles are modeled as assemblages of irregular polyhedra. Modeling is done by a so-called "penalty method" where repulsive forces are applied to prevent interpenetration of the constitutent blocks. Displacements are proportional to the forces, so this is a first-order dynamics method (i.e.there is no inertia). Collision detection among the elements is done via Minkowski summation: compilation of the pairwise differences of the polyhedra vertices, followed by the application of a convex hull. Minkowski summation provides the minimum distance required to resolve a collision, but the location of the overlap region is lost. Thus, further operations are done to recover this information. Given the depth of overlaps and their locations, the positions and orientations of polyhedra are adjusted to reduce the overlap until a structure with minimal interpenetration is produced. Initial calculations done with 100 polyhedra derived from voronoi decomposition of a cube yield results with void fractions in the range of 20-25%. Further results will be reported at the DPS conference. This work was supported by NASA PG&G award NNX07AQ04G.

  5. Reticulation des fibres lignocellulosiques

    NASA Astrophysics Data System (ADS)

    Landrevy, Christel

    Pour faire face à la crise économique la conception de papier à valeur ajoutée est développée par les industries papetières. Le but de se projet est l'amélioration des techniques actuelles de réticulation des fibres lignocellulosiques de la pâte à papier visant à produire un papier plus résistant. En effet, lors des réactions de réticulation traditionnelles, de nombreuses liaisons intra-fibres se forment ce qui affecte négativement l'amélioration anticipée des propriétés physiques du papier ou du matériau produit. Pour éviter la formation de ces liaisons intra-fibres, un greffage sur les fibres de groupements ne pouvant pas réagir entre eux est nécessaire. La réticulation des fibres par une réaction de « click chemistry » appelée cycloaddition de Huisgen entre un azide et un alcyne vrai, catalysée par du cuivre (CuAAC) a été l'une des solutions trouvée pour remédier à ce problème. De plus, une adaptation de cette réaction en milieux aqueux pourrait favoriser son utilisation en milieu industriel. L'étude que nous désirons entreprendre lors de ce projet vise à optimiser la réaction de CuAAC et les réactions intermédiaires (propargylation, tosylation et azidation) sur la pâte kraft, en milieu aqueux. Pour cela, les réactions ont été adaptées en milieu aqueux sur la cellulose microcristalline afin de vérifier sa faisabilité, puis transférée à la pâte kraft et l'influence de différents paramètres comme le temps de réaction ou la quantité de réactifs utilisée a été étudiée. Dans un second temps, une étude des différentes propriétés conférées au papier par les réactions a été réalisée à partir d'une série de tests papetiers optiques et physiques. Mots Clés Click chemistry, Huisgen, CuAAC, propargylation, tosylation, azidation, cellulose, pâte kraft, milieu aqueux, papier.

  6. Development of p-y curves of laterally loaded piles in cohesionless soil.

    PubMed

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75%) was increased in the range of 40-95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method. PMID:24574932

  7. Development of p-y Curves of Laterally Loaded Piles in Cohesionless Soil

    PubMed Central

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75%) was increased in the range of 40–95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method. PMID:24574932

  8. The single pile classification: a new tool for the classification of haemorrhoidal disease and the comparison of treatment results.

    PubMed

    Elbetti, C; Giani, I; Novelli, E; Fucini, C; Martellucci, Jacopo

    2015-12-01

    The purpose of the paper is to compare Goligher Classification with the Single Pile Hemorrhoid Classification (SPHC) to show the possible bias and limits of Goligher's use and the possible advantage with the employment of the new classification. SPHC considers the number of pathological piles(N), the characteristics of each internal pile and the characteristics of each external pile, reporting the presence of a fibrous inelastic redundant pile(F), the presence of the subversion of dentate line or the congestion of the external pile(E) and the presence of not tolerated skin tags(S). From September 2010 to December 2012, 197 consecutive patients were analysed according to both classifications. Considering pathological piles, I and II Goligher patients showed a complete agreement between pathological pile and grade, III Goligher patients had 80.5 % of pathological piles of III grade while IV Goligher patients had only 44.3 % of IV grade pathological piles (p < 0.001). Regarding the distribution of the other anatomical variables: F, E, S described in SPHC, the results showed that F was present in 18.3 % while ES was present in 46.2 %. Goligher's Classification has showed to be an inadequate tool to overview surgical outcome or to compare surgical procedure, particularly for high grades, while SPHC showed to be a feasible instrument both to describe and to compare patients affected by hemorrhoid disease.

  9. Pile-Driving Pressure and Particle Velocity at the Seabed: Quantifying Effects on Crustaceans and Groundfish.

    PubMed

    Miller, James H; Potty, Gopu R; Kim, Hui-Kwan

    2016-01-01

    We modeled the effects of pile driving on crustaceans, groundfish, and other animals near the seafloor. Three different waves were investigated, including the compressional wave, shear wave, and interface wave. A finite element (FE) technique was employed in and around the pile, whereas a parabolic equation (PE) code was used to predict propagation at long ranges from the pile. Pressure, particle displacement, and particle velocity are presented as a function of range at the seafloor for a shallow-water environment near Rhode Island. We discuss the potential effects on animals near the seafloor.

  10. Methods for Predicting Potential Impacts of Pile-Driving Noise on Endangered Sturgeon During Bridge Construction.

    PubMed

    Krebs, Justin; Jacobs, Fred; Conway, Robert; Popper, Arthur N; Moese, Mark; Rollino, John; Racca, Roberto; Martin, Bruce; MacGillivray, Alexander

    2016-01-01

    The potential impacts of pile-driving noise on Hudson River sturgeon during construction of the New NY Bridge were predicted. Abundance data for shortnose and Atlantic sturgeon derived from fisheries sampling were combined with data about the spatial extent of pile-driving noise. This approach was used to calculate the number of sturgeon that could occur within sound level isopleths exceeding peak and cumulative noise criteria used by the National Marine Fisheries Service to determine the incidental take of sturgeon. The number of sturgeon subject to the potential onset of physiological effects during pile driving was predicted to be 35-41 fish for each species.

  11. Investigation experimentale de l'ecoulement et des performances thermiques du nanofluide eau-oxyde de cuivre dans un Micro-Canal Chauffe

    NASA Astrophysics Data System (ADS)

    Rimbault, Benjamin

    Cette these de maitrise presentee par articles visait a etudier le comportement hydraulique et thermique d'un ecoulement de nanofluides en micro-canal chauffe. Nous avons etudie premierement de l'eau distillee, ensuite des melanges de particules d'oxyde de cuivre (taille 29nm) avec de l'eau distillee en concentrations particulaires volumiques 4.5%, 1.03%, et 0.24% (CuO-H2O). L'ecoulement force des differents fluides a ete realise au moyen de pompes a engrenages au sein d'un circuit ferme, comprenant un micro-canal a section rectangulaire (e=1.116mm,1=25.229mm) chauffe sur deux faces paralleles via des cartouches electriques, deux echangeurs de chaleurs en serie, ainsi qu'un debitmetre magnetique. A notre connaissance peu d'etudes sur l'ecoulement de nanofluides d'oxyde de cuivre-eau en micro-canal rectangulaire chauffe sont disponibles dans la litterature, cette recherche sert de contribution. Premierement, une validation avec la litterature a ete effectuee pour le cas d'un ecoulement d'eau entre plaques planes paralleles chauffees. Des essais hydrauliques ont ete realises pour une gamme du nombre de Reynolds allant jusqu'a Re=5000 a temperature constante. Par la suite des essais thermiques jusqu'a Re=2500 ont consiste en une elevation de temperature fixe (20.5°C a 30.5°C) a travers la longueur du micro-canal sous un regime stationnaire. Les resultats ont demontre une augmentation de la perte de pression et du coefficient de frottement des nanofluides sur l'eau pour un meme debit. Une telle augmentation de perte de pression etait de +70%, +25%, et +0 a 30% respectivement pour les concentrations 4.50%, 1.03%, et 0.24%. Concernant la transition laminaire a turbulent les comportements semblaient indiquer une valeur critique semblable entre l'eau et les differentes concentrations avec et sans chauffage a un nombre de Reynolds critique Rem 1000. Nous avons observe une legere augmentation du coefficient de convection thermique avec le debit massique pour les faibles

  12. Mechanical and deformation analyses of pile foundation for supporting structure of off-shore wind turbine at Changhua coast in Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, W. C.; Lin, D. G.

    2015-12-01

    This study investigates the bearing capacities and mechanical behaviors of pile foundation installed on the seabed of wind farm near Chang-Hua coast of western Taiwan for the supporting structure of offshore wind turbine. A series of three-dimensional (3-D) numerical modeling of pile foundation subjected to various types of combined loading were carried out using Plaix-3D finite element program to investigate the interactive behaviors between soil and pile. In the numerical modeling, pile diameter, pile length and pile spacing were selected as design parameters to inspect their effects on the bearing capacities and deformation behaviors of the pile foundation. For a specific design parameter combination, one can obtain the corresponding loading-displacement curve, various ultimate bearing capacities, V-H (Vertical-Horizontal combined loading) ultimate bearing capacity envelope, and p-ycurve of pile foundation. Numerical results indicate that: (1) Large displacement and plastic points at ultimate state mostly distribute and concentrate in the topsoil of seabed and around pile head. (2) The soil resistance on the soil-pile interface is ascending with the increases of depth, pile diameter and pile length. (3) The vertical and horizontal bearing capacities of pile group increase significantly with the increase of pile diameter. (4) The vertical and bending moment capacities of pile group increase greatly with the increase of pile length whereas the horizontal capacity is almost insensitive to pile length. (5) The bending moment of pile is highly influenced by the pile spacing. (6) For different design parameters, the shape of ultimate bearing capacity envelopes of pile group on V-H plane is similar while the envelopes will expand as the design parameters increase. For different loading levels of bending moment, the envelopes on V-H plane will contract gradually as the bending moment loading increasing.

  13. Experimental measurement of the angle of repose of a pile of soft frictionless grains

    NASA Astrophysics Data System (ADS)

    Feitosa, Klebert; Shorts, Daniel

    It is well known that dry granular materials can flow like a liquid, but can also behave as a solid and sustain a finite angle of repose, partially as a result of inter-particle friction. Here we investigate the nature of piles formed with soft frictionless grains and measure its angle of repose. The pile is produced by a continuous bubbling of air into a soapy solution in a narrow container of rectangular cross section. We observe a gentle slope at the water-foam interface whose angle dependents on the viscosity of the liquid. In contrast with sand piles, the fluidized region along the interface is several layers deep. We also find that, unlike sand piles, upon interruption of the gas flux, the slope relaxes back to zero as a result of bubble rearrangements and liquid drainage.

  14. Torsional vibration of a pipe pile in transversely isotropic saturated soil

    NASA Astrophysics Data System (ADS)

    Zheng, Changjie; Hua, Jianmin; Ding, Xuanming

    2016-09-01

    This study considers the torsional vibration of a pipe pile in a transversely isotropic saturated soil layer. Based on Biot's poroelastic theory and the constitutive relations of the transversely isotropic medium, the dynamic governing equations of the outer and inner transversely isotropic saturated soil layers are derived. The Laplace transform is used to solve the governing equations of the outer and inner soil layers. The dynamic torsional response of the pipe pile in the frequency domain is derived utilizing 1D elastic theory and the continuous conditions at the interfaces between the pipe pile and the soils. The time domain solution is obtained by Fourier inverse transform. A parametric study is conducted to demonstrate the influence of the anisotropies of the outer and inner soil on the torsional dynamic response of the pipe pile.

  15. Characterization of preferential and matrix flow through unsaturated waste rock piles with two tracers

    NASA Astrophysics Data System (ADS)

    Blackmore, S.; Harrison, B.; Mayer, K. U.; Smith, L.; Beckie, R. D.

    2013-05-01

    The spatial and temporal characteristics of preferential and matrix flow through waste rock influences seepage chemistries and this information is necessary to predict mass loadings and mineral depletion. Matrix flow can be described by the Richards equation and exhibits longer water-rock interaction times than those in preferential flow paths, which exceed flow rates expected by the experimental observer. Flow regimes through two constructed pile experiments (CPEs) (Pile 4 and 5) at the Antamina mine (Antamina, Peru) were investigated using two tracers. The CPEs have an areal footprint of 36 m (w) x 36 m (l) (height = 10 m) and are comprised of mixed waste rock. Pile 4 is composed of marble and marble/hornfels waste rock, whereas Pile 5 contains marble/hornfels (similar to Pile 4) and intrusive waste rock. Particle size distribution curves of marble to marble/hornfels waste rock reveal these materials are both coarse grained (davg = 23 ± 10 mm) and favor preferential flow regimes. Conversely, intrusive material (found in Pile 5) is significantly finer grained (davg = 1.9 ± 2.7 mm) and favours slower, matrix flow regimes. Despite the finer material in Pile 5, flow volumes from both CPE basal lysimeters reveal similar daily outflows (~2.0 mm/d) and annual evaporation estimates (~ 34%). CPE-specific flow regimes were more accurately defined using two tracer solutes; bromide and chloride. A bromide solution (3 g/L; as LiBr) was applied to CPE crowns in January 2010 as a 5-year rain event at Antamina. The timing of the bromide tracer test, at the height of the wet season, was chosen to yield parameters to define the faster or preferential flow component. The chloride tracer originates from blasting residues on waste rock surfaces. The internally-distributed chloride solute and its presence at the experiment initiation (i.e., the dry season) provide parameters that capture (or characterize) a slower or matrix flow component. Both bromide and chloride breakthrough

  16. An interpretation of the ion pile-up region outside the ionospheric contact surface. [Halley's comet

    NASA Technical Reports Server (NTRS)

    Ip, WING-H.; Schwenn, R.; Rosenbauer, H.; Balsiger, H.; Neugebauer, M.; Shelley, E. G.

    1986-01-01

    The possibility that the formation of the plasma pile-up region at comet Halley as observed by Giotto could be the combined result of field-aligned transport and recombination process is discussed. Giotto measurements support the hypothesis.

  17. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... strength to reach from the top of the marker at the top of the pile to the farthest peripheral edge at the...) of the location for each sample. (A) Tie to a stake or otherwise fasten one of the strings at “b,” the bottom of the pile, as a reference point for finding r. (B) Measure the circumference “c,”...

  18. Stability of spoil piles at two coal mines in Turkey: Geotechnical characterization and design considerations

    SciTech Connect

    Kasmer, O.; Ulusay, R.

    2006-11-15

    One of the major problems in surface mining of coal is the stability of disposed overburden materials. Geotechnical considerations are thus very important in rational planning for disposal, reclamation, treatment, and utilization of mine waste material. The subject of this study is the stability of spoil piles at open pit coal mines located in the Central Anatolia, Turkey. The coal is produced from two adjacent open pits. While a large portion of the spoil piles dumped at the Central Pit has experienced slope failure, no spoil pile instability has been experienced at the South Pit. This article outlines the results of field and laboratory investigations to describe the mechanism of the spoil pile failure in the Central Pit and the geotechnical design considerations for the spoil piles at the South Pit based on the experience gained from the previous spoil failures. Limit equilibrium analysis carried out for the large-scale spoil failure indicated that deep-seated sliding along the interface between underclay and dragline spoil piles and rotational slip through the overburden spoil material may be all occurring simultaneously as water migrates through these areas. Sensitivity analyses revealed that spoil pile instability is not expected at the South Pit when the current spoil placement method is used as long as the generation of high water pressures in the spoil piles is not permitted. Comparisons between the results of finite element analysis and long-term monitoring data also confirmed the results of sensitivity analyses and indicated a vertical deformation associated with compaction of the spoil material.

  19. Reactivity to stressor pile-up in adulthood: effects on daily negative and positive affect.

    PubMed

    Schilling, Oliver K; Diehl, Manfred

    2014-03-01

    This study used data from a 30-day diary study with 289 adults (age range 18-89 years) to model the effects of stressor pile-up on individuals' daily negative affect (NA) and positive affect (PA) and to test for age differences in these effects. Specifically, we developed a new approach to operationalize and model stressor pile-up and evaluated this approach using generalized mixed models, taking into account the gamma response distribution of the highly skewed daily NA data. Findings showed that pile-up of stressors over a 1-week period was significantly coupled with increases in individuals' daily NA above and beyond the effect of concurrent stressors. Findings also showed that the effects of stressor accumulation and concurrent stress were additive rather than multiplicative. Age interacted significantly with stressor accumulation so that a higher age was associated with less NA reactivity to stressor pile-up. Yet, we did not find such an age-related association for NA reactivity to concurrent daily stressors. Daily PA was not associated with daily stress or with stressor pile-up. The operational definition of stressor pile-up presented in this study contributes to the literature by providing a new approach to model the dynamic effects of stress, and by providing new ways of separating the effects of acute stressors from the effects of stressor pile-up. The age differences found in the present study suggest that older adults develop effective emotion regulation skills for handling stressor pile-up, but that they react to acute daily stressors in a similar way than younger adults. PMID:24660797

  20. Noise reduction by the application of an air-bubble curtain in offshore pile driving

    NASA Astrophysics Data System (ADS)

    Tsouvalas, A.; Metrikine, A. V.

    2016-06-01

    Underwater noise pollution is a by-product of marine industrial operations. In particular, the noise generated when a foundation pile is driven into the soil with an impact hammer is considered to be harmful for the aquatic species. In an attempt to reduce the ecological footprint, several noise mitigation techniques have been investigated. Among the various solutions proposed, the air-bubble curtain is often applied due to its efficacy in noise reduction. In this paper, a model is proposed for the investigation of the sound reduction during marine piling when an air-bubble curtain is placed around the pile. The model consists of the pile, the surrounding water and soil media, and the air-bubble curtain which is positioned at a certain distance from the pile surface. The solution approach is semi-analytical and is based on the dynamic sub-structuring technique and the modal decomposition method. Two main results of the paper can be distinguished. First, a new model is proposed that can be used for predictions of the noise levels in a computationally efficient manner. Second, an analysis is presented of the principal mechanisms that are responsible for the noise reduction due to the application of the air-bubble curtain in marine piling. The understanding of these mechanisms turns to be crucial for the exploitation of the maximum efficiency of the system. It is shown that the principal mechanism of noise reduction depends strongly on the frequency content of the radiated sound and the characteristics of the bubbly medium. For piles of large diameter which radiate most of the acoustic energy at relatively low frequencies, the noise reduction is mainly attributed to the mismatch of the acoustic impedances between the seawater and the bubbly layer. On the contrary, for smaller piles and when the radiated acoustic energy is concentrated at frequencies close to, or higher than, the resonance frequency of the air bubbles, the sound absorption within the bubbly layer

  1. Influence of dynamic soil-pile raft-structure interaction: an experimental approach

    NASA Astrophysics Data System (ADS)

    Saha, Rajib; Haldar, Sumanta; Dutta, Sekhar Chandra

    2015-12-01

    Traditionally seismic design of structures supported on piled raft foundation is performed by considering fixed base conditions, while the pile head is also considered to be fixed for the design of the pile foundation. Major drawback of this assumption is that it cannot capture soil-foundation-structure interaction due to flexibility of soil or the inertial interaction involving heavy foundation masses. Previous studies on this subject addressed mainly the intricacy in modelling of dynamic soil structure interaction (DSSI) but not the implication of such interaction on the distribution of forces at various elements of the pile foundation and supported structure. A recent numerical study by the authors showed significant change in response at different elements of the piled raft supported structure when DSSI effects are considered. The present study is a limited attempt in this direction, and it examines such observations through shake table tests. The effect of DSSI is examined by comparing dynamic responses from fixed base scaled down model structures and the overall systems. This study indicates the possibility of significant underestimation in design forces for both the column and pile if designed under fixed base assumption. Such underestimation in the design forces may have serious implication in the design of a foundation or structural element.

  2. Effects of riverbed scour on seismic performance of high-rise pile cap foundation

    NASA Astrophysics Data System (ADS)

    Han, Zhenfeng; Ye, Aijun; Fan, Lichu

    2010-12-01

    To explore the seismic performance of a high-rise pile cap foundation with riverbed scour, a finite element model for foundations is introduced in the OpenSees finite element framework. In the model, a fiber element is used to simulate the pile shaft, a nonlinear p-y element is used to simulate the soil-pile interaction, and the p-factor method is used to reflect the group effects. A global and local scour model is proposed, in which two parameters, the scour depth of the same row of piles and the difference in the scour depth of the upstream pile and the downstream pile, are included to study the influence of scour on the foundation. Several elasto-plastic static pushover analyses are performed on this finite element model. The analysis results indicate that the seismic capacity (or supply) of the foundation is in the worst condition when the predicted deepest global scout depth is reached, and the capacity becomes larger when the local scour depth is below the predicted deepest global scout depth. Therefore, to evaluate the seismic capacity of a foundation, only the predicted deepest global scout depth should be considered. The method used in this paper can be also applied to foundations with other soil types.

  3. Dynamic impedances and free-field vibration analysis of pile groups in saturated ground

    NASA Astrophysics Data System (ADS)

    Shi, Li; Xu, Changjie; Cai, Yuanqiang; Geng, Xueyu

    2014-08-01

    A three-dimensional (3D) numerical model basing on the thin layer element method and the flexible volume method was established for the computation of dynamic impedances and free-field vibrations of rigidly-capped pile groups embedded in saturated ground. The piles were considered as beams and the saturated ground was represented by Biot's three-dimensional elastodynamic theory. By recourse to the thin layer element method, Green function of the three dimensional saturated ground was obtained and then verified. The dynamic interaction of the piles and the saturated ground was solved by using the flexible volume method, in which the piles were discretized into three dimensional Euler-Bernoulli beam elements and the dynamic stiffness matrix of saturated ground was formed at the pile-soil interaction nodes by using the Green function. Impedances of the 2×2 pile group and free-field displacement and pore pressure responses caused by harmonic vertical, lateral and rocking forces (moments) applied at the cap center were presented, respectively, for different soil permeability and excitation frequencies. It is found that the soil permeability and the excitation frequency have significant influence on the impedances and the free-field vibration responses.

  4. Behavioral responses of a harbor porpoise (Phocoena phocoena) to playbacks of broadband pile driving sounds.

    PubMed

    Kastelein, Ronald A; van Heerden, Dorianne; Gransier, Robin; Hoek, Lean

    2013-12-01

    The high under-water sound pressure levels (SPLs) produced during pile driving to build offshore wind turbines may affect harbor porpoises. To estimate the discomfort threshold of pile driving sounds, a porpoise in a quiet pool was exposed to playbacks (46 strikes/min) at five SPLs (6 dB steps: 130-154 dB re 1 μPa). The spectrum of the impulsive sound resembled the spectrum of pile driving sound at tens of kilometers from the pile driving location in shallow water such as that found in the North Sea. The animal's behavior during test and baseline periods was compared. At and above a received broadband SPL of 136 dB re 1 μPa [zero-peak sound pressure level: 151 dB re 1 μPa; t90: 126 ms; sound exposure level of a single strike (SELss): 127 dB re 1 μPa(2) s] the porpoise's respiration rate increased in response to the pile driving sounds. At higher levels, he also jumped out of the water more often. Wild porpoises are expected to move tens of kilometers away from offshore pile driving locations; response distances will vary with context, the sounds' source level, parameters influencing sound propagation, and background noise levels. PMID:24144856

  5. A new method for testing pile by single-impact energy and P-S curve

    NASA Astrophysics Data System (ADS)

    Xu, Zhao-Yong; Duan, Yong-Kang; Wang, Bin; Hu, Yi-Li; Yang, Run-Hai; Xu, Jun; Zhao, Jin-Ming

    2004-11-01

    By studying the pile-formula and stress-wave methods ( e.g., CASE method), the authors propose a new method for testing piles using the single-impact energy and P-S curves. The vibration and wave figures are recorded, and the dynamic and static displacements are measured by different transducers near the top of piles when the pile is impacted by a heavy hammer or micro-rocket. By observing the transformation coefficient of driving energy (total energy), the consumed energy of wave motion and vibration and so on, the vertical bearing capacity for single pile is measured and calculated. Then, using the vibration wave diagram, the dynamic relation curves between the force ( P) and the displacement ( S) is calculated and the yield points are determined. Using the static-loading test, the dynamic results are checked and the relative constants of dynamic-static P-S curves are determined. Then the subsidence quantity corresponding to the bearing capacity is determined. Moreover, the shaped quality of the pile body can be judged from the formation of P-S curves.

  6. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  7. A comprehensive in-pile test of PWR fuel bundle

    NASA Astrophysics Data System (ADS)

    Kang, Rixin; Zhang, Shucheng; Chen, Dianshan

    1991-02-01

    An in-pile test of PWR fuel bundle has been conducted in HWRR at IAE of China. This paper describes the structure of the test bundle (3 × 3-2), fabrication process and quality control of the fuel rod, irradiation conditions and the main Post Irradiation Examination (PIE) results. The test fuel bundle was irradiated under the PWR operation and water chemistry conditions with an average linear power of 381 W/cm and reached an average burnup of 25010 MWd/tU of the fuel bundle. After the test, destructive and non-destructive examination of the fuel rods was conducted at hot laboratories. The fission gas release was 10.4-23%. The ridge height of cladding was 3 to 8 μm. The hydrogen content of the cladding was 80 to 140 ppm. The fuel stack height was increased by 2.9 to 3.3 mm. The relative irradiation growth was about 0.11 to 0.17% of the fuel rod length. During the irradiation test, no fuel rod failure or other abnormal phenomena had been found by the on-line fuel failure monitoring system of the test loop and water sampling analysis. The structure of the test fuel assembly was left undamaged without twist and detectable deformation.

  8. Early corrosion monitoring of prestressed concrete piles using acoustic emission

    NASA Astrophysics Data System (ADS)

    Vélez, William; Matta, Fabio; Ziehl, Paul H.

    2013-04-01

    The depassivation and corrosion of bonded prestressing steel strands in concrete bridge members may lead to major damage or collapse before visual inspections uncover evident signs of damage, and well before the end of the design life. Recognizing corrosion in its early stage is desirable to plan and prioritize remediation strategies. The Acoustic Emission (AE) technique is a rational means to develop structural health monitoring and prognosis systems for the early detection and location of corrosion in concrete. Compelling features are the sensitivity to events related to micro- and macrodamage, non-intrusiveness, and suitability for remote and wireless applications. There is little understanding of the correlation between AE and the morphology and extent of early damage on the steel surface. In this paper, the evidence collected from prestressed concrete (PC) specimens that are exposed to salt water is discussed vis-à-vis AE data from continuous monitoring. The specimens consist of PC strips that are subjected to wet/dry salt water cycles, representing portions of bridge piles that are exposed to tidal action. Evidence collected from the specimens includes: (a) values of half-cell potential and linear polarization resistance to recognize active corrosion in its early stage; and (b) scanning electron microscopy micrographs of steel areas from two specimens that were decommissioned once the electrochemical measurements indicated a high probability of active corrosion. These results are used to evaluate the AE activity resulting from early corrosion.

  9. Tidal Disruption of Rubble-Pile Comets and Asteroids

    NASA Astrophysics Data System (ADS)

    Movshovitz, Naor; Asphaug, E.; Korycansky, D.

    2010-10-01

    Following the investigations of Richardson et al. (2005) and Korycansky and Asphaug (2006, 2008), we study the shape and spin state of rubble-pile asteroids and cometary nuclei, focusing here on the process and aftermath of tidal disruption. A fast and robust commercial physics engine (www.nvidia.com/physx) is used to model thousands of polyhedral elements including self-gravity and intergranular forces such as friction and cohesion. The physics engine has been tested and validated with small scale laboratory experiments (granular avalanche, brazil-nut effects); its speed and its ability to deal with resting contacts allow us to use a variety of element shapes, from simple primitives to arbitrary polyhedra. Here we model the tidal disruption of comet Shoemaker-Levy 9 and other split comets, extending the work of Asphaug and Benz (1996) to include bodies with realistic rubble properties. One result is that a modest cohesion can account for the absence of small tidal-disruption crater chains on Ganymede and Callisto.

  10. The Supercritical Pile GRB Model: The Prompt to Afterglow Evolution

    NASA Technical Reports Server (NTRS)

    Mastichiadis, A.; Kazanas, D.

    2009-01-01

    The "Supercritical Pile" is a very economical GRB model that provides for the efficient conversion of the energy stored in the protons of a Relativistic Blast Wave (RBW) into radiation and at the same time produces - in the prompt GRB phase, even in the absence of any particle acceleration - a spectral peak at energy approx. 1 MeV. We extend this model to include the evolution of the RBW Lorentz factor Gamma and thus follow its spectral and temporal features into the early GRB afterglow stage. One of the novel features of the present treatment is the inclusion of the feedback of the GRB produced radiation on the evolution of Gamma with radius. This feedback and the presence of kinematic and dynamic thresholds in the model can be the sources of rich time evolution which we have began to explore. In particular. one can this may obtain afterglow light curves with steep decays followed by the more conventional flatter afterglow slopes, while at the same time preserving the desirable features of the model, i.e. the well defined relativistic electron source and radiative processes that produce the proper peak in the (nu)F(sub nu), spectra. In this note we present the results of a specific set of parameters of this model with emphasis on the multiwavelength prompt emission and transition to the early afterglow.

  11. Experience with in-pile fission targets at LOHENGRIN

    NASA Astrophysics Data System (ADS)

    Köster, U.; Faust, H.; Materna, T.; Mathieu, L.

    2010-02-01

    The LOHENGRIN fission fragment separator uses actinide targets in a neutron flux of about 5×1014 neutrons/cm2/s in an in-pile position of the high-flux reactor of ILL Grenoble. For fission yield measurements relatively thin targets (tens of μg/cm2) are used, while for nuclear spectroscopy applications targets up to 1 mg/cm2 are employed. This leads to fission rates up to 5×1012/s. The targets are heated by the fission power in vacuum to temperatures of up to 1000C. The radiation damage caused by the fission fragments can reach 50 dpa (displacements per atom) per day, an extremely high value comparable to that caused by irradiation with intense heavy ion beams. Therefore the thick targets that were produced with different methods (painting, spray-painting, electrolysis and molecular plating) all suffer from a burnup that is much quicker than explainable by nuclear transmutation. We discuss physical effects responsible for this additional decrease in fission fragment rate and ways to improve the situation.

  12. Stability of binaries. Part II: Rubble-pile binaries

    NASA Astrophysics Data System (ADS)

    Sharma, Ishan

    2016-10-01

    We consider the stability of the binary asteroids whose members are granular aggregates held together by self-gravity alone. A binary is said to be stable whenever both its members are orbitally and structurally stable to both orbital and structural perturbations. To this end, we extend the stability analysis of Sharma (Sharma [2015] Icarus, 258, 438-453), that is applicable to binaries with rigid members, to the case of binary systems with rubble members. We employ volume averaging (Sharma et al. [2009] Icarus, 200, 304-322), which was inspired by past work on elastic/fluid, rotating and gravitating ellipsoids. This technique has shown promise when applied to rubble-pile ellipsoids, but requires further work to settle some of its underlying assumptions. The stability test is finally applied to some suspected binary systems, viz., 216 Kleopatra, 624 Hektor and 90 Antiope. We also see that equilibrated binaries that are close to mobilizing their maximum friction can sustain only a narrow range of shapes and, generally, congruent shapes are preferred.

  13. Etude de la performance de piles a combustible microbiennes et l'effet des materiaux d'electrodes

    NASA Astrophysics Data System (ADS)

    Martin, Edith

    Recent climate change has brought a whole new dimension to the energy field since now we must change our primary source, fossil fuels. The microbial fuel cell (MFC) technology emerged as a result of recent efforts in the development of alternative sources of energy. This project aims to improve the performance maximization of such celsl. It is assumed that the microbial fuel cells' functioning is influenced by the operation conditions as well as the biofilm development and other limitations. It is also appropriate to suppose that the electrode materials also have consequences on either the microorganisms' activity or the electrochemical reaction reactivity. Thus, various operating conditions and configurations are tested to identify the specific effects of these changes on cell performance. Also, the development of the biofilm is extensively studied under various conditions to improve the electrons transfer between the active biofilm and the anode. These experiments and analyses permitted to identify various effects that can improve the microbial fuel cell performance. Thus, the influence of organic load (of glucose and acetate), pH and operating temperature of the fuel cell has been shown and optimal values were determined, leading to a significant increase in the anodic biofilm activity and a decrease of the methanogens activity, the latter reducing the coulombic efficiency by diverting a non-negligible substrate amount for their benefit. Hence, organic loading of 2 to 4 g L-1 day-1, pH between 6,25 and 6,5 as well as high cathode temperature (62 °C) but moderate anode temperature (30 °C) caused a maximum power generation increase to 19,2 W m -3. During the experiments with acetate as substrate, distance between electrodes and fuel cell volume have been reduced, leading to a power density of 92,4 W m-3. All these observations are the subject of the first article presented in this thesis. Since the microbial fuel cell power generation depends on the number of anode-reducing microorganisms populating the biofilm, this relationship was deepened in the second manuscript. This article, which intended to monitor the biofilm development, highlights the influence of external load changing rate during the active biofilm growth. Thus, when the external load is adjusted rapidly to approach the cell internal resistance, electrons exchange is enhanced as well as the proliferation of microorganisms responsible of these electrons generation. By promoting faster anode-reducing microorganisms growth, other species are somewhat disadvantaged and substrate consumption is primarily involved in the electricity production rather than any other unwanted products (eg.: methane). This article also demonstrates the influence of the biofilm development level on the diffusion limitation of the anodic reaction, a limitation that becomes more pronounced as the biofilm grows. The third article clarifies the diffusion limitation of the charge transfer at the anode. Therefore, the organic load variation of acetate in microbial fuel cells with carbon felt (3D) and carbon paper (2D) anodes as well as the electrolyte conductivity decrease has targeted protons diffusion out of the biofilm as the current generation limitation. In addition, a secondary electrochemical reaction has been identified at the anode, creating an electrode resistance increase and thereby a slight power output decrease. Finally, multiple electrochemical analyses helped to establish with certainty that the electron transfer mechanism carried out by anode-reducing microorganisms is by direct contact with the anode via microorganisms themselves or the conductive biofilm matrix, cytochromes being responsible for the electrons transport in both cases. The last manuscript deals with new cathode materials (carbon, Mn 2O3 and Fe2O3) evaluation in comparison to a platinum cathode. These materials were chosen for their potential to stimulate the proliferation of microorganisms capable of influencing cathode activity in order to obtain a biocathode; however, this phenomenon has not been verified. (Abstract shortened by UMI.)

  14. Deformation Measurement of a Driven Pile Using Distributed Fibre-optic Sensing

    NASA Astrophysics Data System (ADS)

    Monsberger, Christoph; Woschitz, Helmut; Hayden, Martin

    2016-03-01

    New developments in distributed fibre-optic sensing allow the measurement of strain with a very high precision of about 1 µm / m and a spatial resolution of 10 millimetres or even better. Thus, novel applications in several scientific fields may be realised, e. g. in structural monitoring or soil and rock mechanics. Especially due to the embedding capability of fibre-optic sensors, fibre-optic systems provide a valuable extension to classical geodetic measurement methods, which are limited to the surface in most cases. In this paper, we report about the application of an optical backscatter reflectometer for deformation measurements along a driven pile. In general, pile systems are used in civil engineering as an efficient and economic foundation of buildings and other structures. Especially the length of the piles is crucial for the final loading capacity. For optimization purposes, the interaction between the driven pile and the subsurface material is investigated using pile testing methods. In a field trial, we used a distributed fibre-optic sensing system for measuring the strain below the surface of an excavation pit in order to derive completely new information. Prior to the field trial, the fibre-optic sensor was investigated in the laboratory. In addition to the results of these lab studies, we briefly describe the critical process of field installation and show the most significant results from the field trial, where the pile was artificially loaded up to 800 kN. As far as we know, this is the first time that the strain is monitored along a driven pile with such a high spatial resolution.

  15. Ability of subsoils to buffer extremely acidic simulated coal-pile leachates

    SciTech Connect

    Zelmanowitz, S.; Boyle, W.C.; Armstrong, D.E.; Park, J.K.

    1995-11-01

    Coal piles stored directly on soil surfaces may pose a risk of ground-water contamination, particularly when extremely acidic coal-pile leachates, which contain elevated concentrations of heavy metals, are generated. Soil-column experiments were run to evaluate the ability of a sand, a silt loam, and a silt loam amended with 4% CaCO{sub 3} to buffer dilute H{sub 2}SO{sub 4} solutions (pH 3.5 and 1.5) and a synthetic coal-pile leachate (a pH 1.5 H{sub 2}SO{sub 4} solution containing metal sulfate salts). Both silt-loam soils were able to buffer the pH 3.5 H{sub 2}SO{sub 4} solution for the entire leaching period (more than 50 pore volumes), but the sand was not. The buffering capacities of all three soils were insufficient to neutralize pH 1.5 acid and synthetic coal-pile leachates. The sand exhibited the least buffering, and the silt loam at a low flow rate and the silt loam amended with CaCO{sub 3} showed the greatest buffering. The buffering capacities of both silt loam soils were exhausted more rapidly when leached with synthetic coal-pile leachate rather than pH 1.5 H{sub 2}SO{sub 4} solution. This suggests that soil-buffering studies using pure acid solutions may underpredict contamination due to coal-pile leachates. The results indicate that there is a potential for ground-water contamination due to coal-pile storage, particularly where leachates are acidic ad coarse textured soils exist. Coal storage practices should be adopted that protect soils and ground water from acidification and metals contamination.

  16. The Supercritical Pile GRB Model: The Prompt to Afterglow Evolution

    NASA Technical Reports Server (NTRS)

    Kazanas, Demosthenes

    2008-01-01

    The 'Supercritical Pile' is a very economical gamma ray burst (GRB) model that provides for the efficient conversion of the energy stored in the protons of a Relativistic Blast Wave (RBW) into radiation and at the same time produces - in the prompt GRB phase, even in the absence of any particle acceleration - a spectral peak at an energy sim 1 MeV. We extend this model to include also the evolution of the RBW Lorentz factor Gamma and thus follow the spectral and temporal features of this model into the early GRB afterglow stage. One of the novel features of the present treatment is the inclusion of the feedback of the GRB produced radiation on the evolution of Gamma with radius. This feedback and the presence of kinematic and dynamic thresholds in the model can be the sources of rich time evolution which we have begun to explore. In particular, one can this way obtain afterglow light curves with steep decays followed by the more conventional flatter afterglow slopes, while at the same time preserving the desirable features of the model, i.e. the well defined relativistic electron source and radiative processes that produce the proper peak in the nu F spectra. Furthermore, the existence of a kinematic threshold in this model provides for a operational distinction of the prompt and afterglow GRB stages; in fact, the afterglow stage sets in when the RBW Lorentz factor cannot anymore fulfill the kinematic condition for pair formation in the photon - proton pair production reactions that constitute the fundamental process for the dissipation of the blast wave kinetic energy. We present the results of a specific set of parameters of this model with emphasis on the multiwavelength prompt emission and transition to the early afterglow.

  17. The formation of technic soil in a revegetated uranium ore waste rock pile (Limousin, France)

    NASA Astrophysics Data System (ADS)

    Boekhout, Flora; Gérard, Martine; Kanzari, Aisha; Calas, Georges; Descostes, Michael

    2014-05-01

    Mining took place in France between 1945 and 2001 during which time ~210 different sites were exploited and/or explored. A total of 76 Kt of uranium was produced, 52 Mt of ore was extracted, but also 200 Mt of waste rocks was produced, the majority of which, with uranium levels corresponding to the natural environment. So far, the processes of arenisation and technic soil formation in waste rock piles are not well understood but have important implications for understanding the environmental impact and long-term speciation of uranium. Understanding weathering processes in waste rock piles is essential to determine their environmental impact. The main objectives of this work are to assess 1) the micromorphological features and neo-formed U-bearing phases related to weathering and 2) the processes behind arenisation of the rock pile. The site that was chosen is the Vieilles Sagnes waste rock pile in Fanay (Massif Central France) that represents more or less hydrothermally altered granitic rocks that have been exposed to weathering since the construction of the waste rock pile approximately 50 years ago. Two trenches were excavated to investigate the vertical differentiation of the rock pile. This site serves as a key location for studying weathering processes of waste rock piles, as it has not been reworked after initial construction and has therefore preserved information on the original mineralogy of the waste rock pile enabling us to access post emplacement weathering processes. The site is currently overgrown by moss, meter high ferns and small trees. At present day the rock pile material can be described as hydrothermally altered rocks and rock fragments within a fine-grained silty clay matrix exposed to surface conditions and weathering. A sandy "paleo" technic soil underlies the waste rock pile and functions as a natural liner by adsorption of uranium on clay minerals. Post-mining weathering of rock-pile material is superimposed on pre-mining hydrothermal and

  18. Kinematic Interaction and Rocking Effects on the Seismic Response of Viaducts on Pile Foundations

    SciTech Connect

    Dezi, F.; Carbonari, S.; Leoni, G.

    2008-07-08

    This paper is aimed at providing a contribution for a more accurate and effective design of bridges founded on piles. A numerical model is employed herein to determine the stresses and displacements in the piles taking into account soil-foundation-structure interaction. A 3D finite element approach is developed for piles and superstructure whereas the soil is assumed to be a Winkler-type medium. The method is applied to single piers representative for a class of bridges. Varying the soil layers characteristics and the pile spacing (from 3 to 5 diameters), bending and axial stresses along piles as well as the pier base shear are computed. A comparison with respect to a fixed-base model is provided. Special issues such as the contribution of the soil profile, of the local amplification and of the rocking at the foundation level are discussed. Soil-structure interaction is found to be essential for effective design of bridges especially for squat piers and soft soil.

  19. Costs of Harvesting, Storing in a Large Pile, and Transporting Corn Stover in a Wet Form

    SciTech Connect

    Turhollow Jr, Anthony F; Sokhansanj, Shahabaddine

    2007-01-01

    Corn stover is potentially an attractive biomass resource, but must be stored if used to supply a biorefinery year-round. Based on experience with successfully storing water-saturated large piles of bagasse for the pulping industry, Atchison and Hettenhaus (2003) proposed that such a system can also be applied to corn stover. Regardless of the technical feasibility of this system, in this article we estimate the cost of harvesting corn stover in a single pass with corn grain, delivering the chopped biomass to a storage pile, storing the stover in a wet form in a large pile at 75% moisture in a 211,700-dry Mg facility within a radius of 24 km from the field, and transporting the stover 64 km to a biorefinery. Field-ground corn stover can be delivered to a biorefinery by rail for $55 to $61/dry Mg. Truck transport is more expensive, $71 to $77/dry Mg. To achieve a minimum cost in the system proposed by Atchison and Hettenhaus, it is necessary to field densify stover to 74 dry kg/m3, without losing combine field efficiency, have a large storage pile to spread fixed costs of storage over enough biomass, and use rail transportation. Compared to storage in an on-farm bunker silo at $60/dry Mg, there are limited circumstances in which large pile storage has a cost advantage.

  20. Isotopically enriched ammonium shows high nitrogen transformation in the pile top zone of dairy manure compost

    NASA Astrophysics Data System (ADS)

    Maeda, Koki; Toyoda, Sakae; Yano, Midori; Hattori, Shohei; Fukasawa, Makoto; Nakajima, Keiichi; Yoshida, Naohiro

    2016-03-01

    Nitrogen isotope ratios (δ15N) of NH4+ in dairy manure compost piles with and without bulking agent (10 % w/w) were compared to understand the effects of the use of bulking agent on nitrogen conversion during manure composting. The δ15N-NH4+ values in each of three pile zones (top, side and core) were also compared. At the end of the process, piles with bulking agent showed significantly higher δ15N values (17.7 ± 1.3 ‰) than piles without bulking agent (11.8 ± 0.9 ‰), reflecting the significantly higher nitrogen conversion and NH3 loss in the former. The samples from the top zone, especially in the piles with bulking agent, showed very high NH4+ concentrations with significantly high 15N (δ15N: 12.7-29.8 ‰) values, indicating that extremely high nitrogen conversion, nitrification-denitrification activity of the microbes and NH3 volatilization occurred in this zone.

  1. Strongly non-local modelling of dislocation transport and pile-up

    NASA Astrophysics Data System (ADS)

    Rezaei Mianroodi, Jaber; Peerlings, Ron; Svendsen, Bob

    2016-04-01

    The purpose of this work is the continuum modelling of transport and pile-up of infinite discrete dislocation walls driven by non-local interaction and external loading. To this end, the underlying model for dislocation wall interaction is based on the non-singular Peierls-Nabarro (PN) model for the dislocation stress field. For simplicity, attention is restricted to walls consisting of single-sign dislocations and to continuous wall distributions on a single glide plane. In this context, the influence of strongly non-local (SNL; long-range) interaction, and its approximation as weakly non-local (WNL; short-range) are studied in the context of interaction- and external-load-driven wall pile-up at a boundary. The pile-up boundary is modelled via a spatially dependent dislocation mobility which decreases to zero at the boundary. The pile-up behaviour predicted by the current SNL-based continuous wall distribution modelling is consistent with that predicted by discrete wall distribution modelling. Both deviate substantially from the pile-up behaviour predicted by WNL-based continuous wall distribution modelling. As such, it is clearly essential to account in continuum models for the intrinsic SNL character of the interaction between same-sign dislocations 'close' to the boundary. Gradient-based WNL 'approximation' of this interaction is not justified.

  2. Load-Deflection response of transversely isotropic piles under lateral loads

    NASA Astrophysics Data System (ADS)

    Han, J.; Frost, J. D.

    2000-04-01

    In general, pile materials are assumed to be isotropic during the analysis of the load-deflection response of piles under lateral loads. However, commonly used materials such as reinforced concrete and timber as well as potentially promising new pile materials such as fiber reinforced polymers are typically transversely isotropic materials. Experimental studies have shown that transversely isotropic materials have a high ratio of section longitudinal modulus to the section in-plane shear modulus (Ezz/Gxz) compared to the value for isotropic materials. The high modulus ratio leads to a more significant shear deformation effect in beam bending. To account for the shear deformation effect, the Timoshenko Beam Theory has been adopted in deriving the solutions for the load-deflection response of transversely isotropic piles under lateral loads instead of the Classical (Euler-Bernoulli) Beam Theory. The load-deflection responses depend on the shear effect coefficient, the lateral soil resistance, the embedment ratio, and the boundary conditions. The deflection of the pile, if the shear deformation effect is considered, is always larger than if it is neglected.

  3. Effects of the Tip Location on Single Piles Subjected to Surcharge and Axial Loads

    PubMed Central

    Wang, Dubo

    2013-01-01

    When applying axial load on piles subjected to negative skin friction (NSF), the yielded NSF is gradually eliminated. The process is notably influenced by the tip location (Y) and still a lack of understanding. This paper reports three-dimensional numerical simulations with tip locations Y = 1.00 pile diameter (D), 0.25D, 0.00D, and −1.00D. It is found that, against expectations, the dragload and NSF are not proportionally related to the tip location. When maximum dragload (Pmax) is eventually eliminated due to an axial load, there is also a negative crest of the skin friction, indicating that NSF still exists based on the criterion of the dragload reduction. The side resistance of the piles with Y = 1.00D and 0.25D is almost fully mobilised, which is demonstrated by the increment of end resistance that greatly increases with the larger axial loads. However, the side resistance of the piles with Y = 0.00D and −1.00D has a potential capacity to carry more loads with continued displacement since the increment of end resistance increases almost linearly with axial load. Therefore, when designing the pile foundation, the inclusion of the NSF should be governed by the amount of axial load to be resisted. PMID:24459418

  4. Spontaneous vegetation on overburden piles in the Coal Basin of Santa Catarina, Brazil

    SciTech Connect

    dos Santos, R.; Citadini-Zanette, V.; Leal-Filho, L.S.; Hennies, W.T.

    2008-09-15

    The objective of this work was to select indigenous vegetal species for restoration programs aiming at the regeneration of ombrophilous dense forest. Thirty-five spoil piles located in the county of Sideropolis, Santa Catarina, that received overburden disposal for 39 years (1950-1989) were selected for study because they exhibited remarkable spontaneous regrowth of trees compared to surrounding spoil piles. Floristic inventory covered the whole area of the 35 piles, whereas survey on phytosociology and natural regeneration studies were conducted in 70 plots distributed along the 35 piles. Floristic inventory recorded 83 species from 28 botanical families. Herbaceous terricolous plants constituted the predominant species (47.0%), followed by shrubs (26.5%), trees (19.3%), and vines (7.2%). Severe chemical (acidic pH and lack of nutrients) and physical (coarse substrate and slope angle of 40-50{sup o} characteristics displayed by the overburden piles constituted limitations to floristic diversity and size of indigenous trees, indicating the need for substrate reclamation prior to forest restoration.

  5. Development of an air bubble curtain to reduce underwater noise of percussive piling.

    PubMed

    Würsig, B; Greene, C R; Jefferson, T A

    2000-02-01

    Underwater bubbles can inhibit sound transmission through water due to density mismatch and concomitant reflection and absorption of sound waves. For the present study, a perforated rubber hose was used to produce a bubble curtain, or screen, around pile-driving activity in 6-8-m depth waters of western Hong Kong. The percussive hammer blow sounds of the pile driver were measured on 2 days at distances of 250, 500, and 1000 m; broadband pulse levels were reduced by 3-5 dB by the bubble curtain. Sound intensities were measured from 100 Hz to 25.6 kHz, and greatest sound reduction by the bubble curtain was evident from 400 to 6400 Hz. Indo-Pacific hump-backed dolphins (Sousa chinensis) occurred in the immediate area of the industrial activity before and during pile driving, but with a lower abundance immediately after it. While hump-backed dolphins generally showed no overt behavioral changes with and without pile driving, their speeds of travel increased during pile driving, indicating that bubble screening did not eliminate all behavioral responses to the loud noise. Because the bubble curtain effectively lowered sound levels within 1 km of the activity, the experiment and its application during construction represented a success, and this measure should be considered for other appropriate areas with high industrial noises and resident or migrating sound-sensitive animals.

  6. Effect of heterogeneity and anisotropy related to the construction method on transfer processes in waste rock piles

    NASA Astrophysics Data System (ADS)

    Lahmira, Belkacem; Lefebvre, René; Aubertin, Michel; Bussière, Bruno

    2016-01-01

    Waste rock piles producing acid mine drainage (AMD) are partially saturated systems involving multiphase (gas and liquid) flow and coupled transfer processes. Their internal structure and heterogeneous properties are inherited from their wide-ranging material grain sizes, their modes of deposition, and the underlying topography. This paper aims at assessing the effect of physical heterogeneity and anisotropy of waste rock piles on the physical processes involved in the generation of AMD. Generic waste rock pile conditions were represented with the numerical simulator TOUGH AMD based on those found at the Doyon mine waste rock pile (Canada). Models included four randomly distributed material types (coarse, intermediate, fine and very fine-grained). The term "randomly" as used in this study means that the vertical profile and spatial distribution of materials in waste rock piles (internal structure) defy stratigraphy principles applicable to natural sediments (superposition and continuity). The materials have different permeability and capillary properties, covering the typical range of materials found in waste rock piles. Anisotropy with a larger horizontal than vertical permeability was used to represent the effect of pile construction by benches, while the construction by end-dumping was presumed to induce a higher vertical than horizontal permeability. Results show that infiltrated precipitation preferentially flows in fine-grained materials, which remain almost saturated, whereas gas flows preferentially through the most permeable coarse materials, which have higher volumetric gas saturation. Anisotropy, which depends on pile construction methods, often controls global gas flow paths. Construction by benches favours lateral air entry close to the pile slope, whereas end-dumping leads to air entry from the surface to the interior of the pile by secondary gas convection cells. These results can be useful to construct and rehabilitate waste rock piles to minimize

  7. Effect of heterogeneity and anisotropy related to the construction method on transfer processes in waste rock piles.

    PubMed

    Lahmira, Belkacem; Lefebvre, René; Aubertin, Michel; Bussière, Bruno

    2016-01-01

    Waste rock piles producing acid mine drainage (AMD) are partially saturated systems involving multiphase (gas and liquid) flow and coupled transfer processes. Their internal structure and heterogeneous properties are inherited from their wide-ranging material grain sizes, their modes of deposition, and the underlying topography. This paper aims at assessing the effect of physical heterogeneity and anisotropy of waste rock piles on the physical processes involved in the generation of AMD. Generic waste rock pile conditions were represented with the numerical simulator TOUGH AMD based on those found at the Doyon mine waste rock pile (Canada). Models included four randomly distributed material types (coarse, intermediate, fine and very fine-grained). The term "randomly" as used in this study means that the vertical profile and spatial distribution of materials in waste rock piles (internal structure) defy stratigraphy principles applicable to natural sediments (superposition and continuity). The materials have different permeability and capillary properties, covering the typical range of materials found in waste rock piles. Anisotropy with a larger horizontal than vertical permeability was used to represent the effect of pile construction by benches, while the construction by end-dumping was presumed to induce a higher vertical than horizontal permeability. Results show that infiltrated precipitation preferentially flows in fine-grained materials, which remain almost saturated, whereas gas flows preferentially through the most permeable coarse materials, which have higher volumetric gas saturation. Anisotropy, which depends on pile construction methods, often controls global gas flow paths. Construction by benches favours lateral air entry close to the pile slope, whereas end-dumping leads to air entry from the surface to the interior of the pile by secondary gas convection cells. These results can be useful to construct and rehabilitate waste rock piles to minimize

  8. Effect of heterogeneity and anisotropy related to the construction method on transfer processes in waste rock piles.

    PubMed

    Lahmira, Belkacem; Lefebvre, René; Aubertin, Michel; Bussière, Bruno

    2016-01-01

    Waste rock piles producing acid mine drainage (AMD) are partially saturated systems involving multiphase (gas and liquid) flow and coupled transfer processes. Their internal structure and heterogeneous properties are inherited from their wide-ranging material grain sizes, their modes of deposition, and the underlying topography. This paper aims at assessing the effect of physical heterogeneity and anisotropy of waste rock piles on the physical processes involved in the generation of AMD. Generic waste rock pile conditions were represented with the numerical simulator TOUGH AMD based on those found at the Doyon mine waste rock pile (Canada). Models included four randomly distributed material types (coarse, intermediate, fine and very fine-grained). The term "randomly" as used in this study means that the vertical profile and spatial distribution of materials in waste rock piles (internal structure) defy stratigraphy principles applicable to natural sediments (superposition and continuity). The materials have different permeability and capillary properties, covering the typical range of materials found in waste rock piles. Anisotropy with a larger horizontal than vertical permeability was used to represent the effect of pile construction by benches, while the construction by end-dumping was presumed to induce a higher vertical than horizontal permeability. Results show that infiltrated precipitation preferentially flows in fine-grained materials, which remain almost saturated, whereas gas flows preferentially through the most permeable coarse materials, which have higher volumetric gas saturation. Anisotropy, which depends on pile construction methods, often controls global gas flow paths. Construction by benches favours lateral air entry close to the pile slope, whereas end-dumping leads to air entry from the surface to the interior of the pile by secondary gas convection cells. These results can be useful to construct and rehabilitate waste rock piles to minimize

  9. Peste des petits ruminants.

    PubMed

    Parida, S; Muniraju, M; Mahapatra, M; Muthuchelvan, D; Buczkowski, H; Banyard, A C

    2015-12-14

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants.

  10. Peste des petits ruminants.

    PubMed

    Parida, S; Muniraju, M; Mahapatra, M; Muthuchelvan, D; Buczkowski, H; Banyard, A C

    2015-12-14

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  11. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  12. Frost and ice formation in the air convection pile permafrost protection device

    SciTech Connect

    Reid, R.L.; Hudgins, E.H.

    1982-09-01

    Experimental studies on frost and ice growth under simulated summer conditions were performed on a 3.0-m (10-ft) model of an air convection pile. The air convection pile is a thermosyphon-type permafrost protection device which has been considered for use in arctic construction projects. The device consists of an outer tube, usually 45.75 cm (18 in.) in diameter, extending 3.05 to 18.3 m (10 to 60 ft) into the permafrost. This outer tube contains a shorter concentric 25.4-cm- (10in.) dia inner tube. Data was taken for typical arctic temperatures and humidities and for simulated above-ground heights of 0.153, 1.373, and 2.88 m (0.5, 4.5, and 7.5 ft). The results have shown that the ice growth is governed by the concentration gradient in the annulus of the pile.

  13. Acoustic emission signal processing technique to characterize reactor in-pile phenomena

    SciTech Connect

    Agarwal, Vivek; Tawfik, Magdy S.; Smith, James A.

    2015-03-31

    Existing and developing advanced sensor technologies and instrumentation will allow non-intrusive in-pile measurement of temperature, extension, and fission gases when coupled with advanced signal processing algorithms. The transmitted measured sensor signals from inside to the outside of containment structure are corrupted by noise and are attenuated, thereby reducing the signal strength and the signal-to-noise ratio. Identification and extraction of actual signal (representative of an in-pile phenomenon) is a challenging and complicated process. In the paper, empirical mode decomposition technique is utilized to reconstruct actual sensor signal by partially combining intrinsic mode functions. Reconstructed signal will correspond to phenomena and/or failure modes occurring inside the reactor. In addition, it allows accurate non-intrusive monitoring and trending of in-pile phenomena.

  14. Radon flux measurements on Gardinier and Royster phosphogypsum piles near Tampa and Mulberry, Florida

    SciTech Connect

    Hartley, J.N.; Freeman, H.D.

    1986-01-01

    As part of the planned Environmental Protection Agency (EPA) radon flux monitoring program for the Florida phosphogypsum piles, Pacific Northwest Laboratory (PNL), under contract to the EPA, constructed 50 large-area passive radon collection devices and demonstrated their use at two phosphogypsum piles near Tampa and Mulberry, Florida. The passive devices were also compared to the PNL large-area flow-through system. The main objectives of the field tests were to demonstrate the use of the large-area passive radon collection devices to EPA and PEI personnel and to determine the number of radon flux measurement locations needed to estimate the average radon flux from a phosphogypsum pile. This report presents the results of the field test, provides recommendations for long-term monitoring, and includes a procedure for making the radon flux measurements.

  15. Development of a full-length external-fuel thermionic converter for in-pile testing.

    NASA Technical Reports Server (NTRS)

    Schock, A.; Raab, B.

    1971-01-01

    Description of an external-fuel thermionic converter which utilizes a thoriated-tungsten fuel-emitter body. Performance in out-of-pile tests was comparable to that of an arc-cast tungsten emitter body, with 400-eW output power (about 5 W/sq cm) at 10.8% efficiency. Maximum fuel clad temperature averaged from 1650 to 1700 C during the 300-hour test. This converter has been processed for in-pile testing. The various processing steps, including the installation of six emitter thermocouples, encapsulation in the secondary container, and joining to the fission-gas collection system, are described in detail. In addition to the converter assembly, a doubly contained fission gas collection assembly with radiation-hardened differential pressure transducers was fabricated. The experiment support plate required for the in-pile test, containing electrically insulated instrumentation feedthroughs and coolant line feedthroughs to the vacuum test chamber, was also fabricated.

  16. Design of an external-fueled thermionic diode for in-pile testing.

    NASA Technical Reports Server (NTRS)

    Ernst, D. M.; Peelgren, M. L.

    1971-01-01

    Description of an external-fueled thermionic diode suitable for in-pile testing in a research reactor. The active electrode area is 94 sq cm. The 10-in. long, 1.5-in.-OD emitter body is tungsten 2% thoria. The fuel is contained in six 0.4-in.-diam holes equally spaced about the 0.5-in. central emitter hole. The collector is niobium-1% zirconium. The expected diode performance is 6 W/sq cm at 2000 K. In addition to following the constraints imposed by the in-pile testing and the electrically heated performance mapping prior to insertion in-pile, the diode will have end configurations prototypical of those anticipated for a flow-through, NaK-cooled, external-fuel thermionic reactor.

  17. Application of self-diagnosis FRP to concrete pile for health monitoring

    NASA Astrophysics Data System (ADS)

    Nishimura, Hitoshi; Sugiyama, Takeshi; Okuhara, Yoshiki; Shin, Soon-Gi; Matsubara, Hideaki; Yanagida, Hiroaki

    2000-06-01

    The function and performance of the self-diagnosis composites embedded in concrete blocks and piles were investigated by bending tests and electrical resistance measurements. Carbon powder (CP) and carbon fiber (CF) were introduced in glass fiber reinforced plastics composites to obtain electrical conductivity. The CP composite has commonly good performances in various bending tests of block and pile specimens, comparing to the CF composite. The electrical resistance of the CP composite increases in a small strain to response remarkably micro-crack formation at about 200 μ strain and to detect well to smaller deformations before the crack formation. The CP composite posses a continuous resistance change up to a large strain level near the final fracture of concrete structures reinforced by steel bars. It has been concluded that the self-diagnosis composite is fairly useful for the measurement of damage and fracture in concrete blocks and piles.

  18. Acoustic Emission Signal Processing Technique to Characterize Reactor In-Pile Phenomena

    SciTech Connect

    Vivek Agarwal; Magdy Samy Tawfik; James A Smith

    2014-07-01

    Existing and developing advanced sensor technologies and instrumentation will allow non-intrusive in-pile measurement of temperature, extension, and fission gases when coupled with advanced signal processing algorithms. The transmitted measured sensor signals from inside to the outside of containment structure are corrupted by noise and are attenuated, thereby reducing the signal strength and signal-to-noise ratio. Identification and extraction of actual signal (representative of an in-pile phenomenon) is a challenging and complicated process. In this paper, empirical mode decomposition technique is proposed to reconstruct actual sensor signal by partially combining intrinsic mode functions. Reconstructed signal corresponds to phenomena and/or failure modes occurring inside the reactor. In addition, it allows accurate non-intrusive monitoring and trending of in-pile phenomena.

  19. Enhancements to High Temperature In-Pile Thermocouple Performance

    SciTech Connect

    J. C. Crepeau; J. L. Rempe; J. E. Daw; D. L. Knudson; K. G. Condie; S. C. Wilkins

    2008-03-01

    A joint University of Idaho (UI) and Idaho National Laboratory (INL) University Nuclear Research Initiative (UNERI) was to initiated to extend initial INL efforts to develop doped lybdenum/niobium alloy High Temperature Irradiation Resistant Thermocouples (HTIR-TCs). The overall objective of this UNERI was to develop recommendations for an optimized thermocouple design for high temperature, long duration, in-pile testing by expanding upon results from initial INL efforts. Tasks to quantify the impact of candidate enhancements, such as alternate alloys, alternate geometries, and alternate thermocouple fabrication techniques, on thermocouple performance were completed at INL's High Temperature Test Laboratory (HTTL), a state of the art facility equipped with specialized equipment and trained staff in the area of high temperature instrumentation development and evaluation. Key results of these evaluations, which are documented in this report, are as follows. The doped molybdenum and Nb-1%Zr, which were proposed in the initial INL HTIR-TC design, were found to retain ductility better than the developmental molybdenum-low niobium alloys and the niobium-low molybdenum alloys evaluated. Hence, the performance and lower cost of the commercially available KW-Mo makes a thermocouple containing KW-Mo and Nb-1%Zr the best option at this time. HTIR-TCs containing larger diameter wires offer the potential to increase HTIR-TC stability and reliability at higher temperatures. HTIR-TC heat treatment temperatures and times should be limited to not more than 100 °C above the proposed operating temperatures and to durations of at least 4 to 5 hours. Preliminary investigations suggest that the performance of swaged and loose assembly HTIR-TC designs is similar. However, the swaged designs are less expensive and easier to construct. In addition to optimizing HTIR-TC performance, This UNERI project provided unique opportunities to several University of Idaho students, allowing them to

  20. Enhancements to High Temperature In-Pile Thermocouple Performance

    SciTech Connect

    J.C. Crepeau; J.L. Rempe; J.E. Daw; D.L. Knudson: K.G. Condie; S.C. Wilkins

    2008-03-31

    A joint University of Idaho (UI) and Idaho National Laboratory (INL) University Nuclear Research Initiative (UNERI) was to initiated to extend initial INL efforts to develop doped molybdenum/niobium alloy High Temperature Irradiation Resistant Thermocouples (HTIR-TCs). The overall objective of this UNERI was to develop recommendations for an optimized thermocouple design for high temperature, long duration, in-pile testing by expanding upon results from initial INL efforts. Tasks to quantify the impact of candidate enhancements, such as alternate alloys, alternate geometries, and alternate thermocouple fabrication techniques, on thermocouple performance were completed at INL's High Temperature Test Laboratory (HTTL), a state of the art facility equipped with specialized equipment and trained staff in the area of high temperature instrumentation development and evaluation. Key results of these evaluations, which are documented in this report, are as follows. The doped molybdenum and Nb-1%Zr, which were proposed in the initial INL HTIR-TC design, were found to retain ductility better than the developmental molybdenum-low niobium alloys and the niobium-low molybdenum alloys evaluated. Hence, the performance and lower cost of the commercially available KW-Mo makes a thermocouple containing KW-Mo and Nb-1%Zr the best option at this time. HTIR-TCs containing larger diameter wires offer the potential to increase HTIR-TC stability and reliability at higher temperatures. HTIR-TC heat treatment temperatures and times should be limited to not more than 100 C above the proposed operating temperatures and to durations of at least 4 to 5 hours. Preliminary investigations suggest that the performance of swaged and loose assembly HTIR-TC designs is similar. However, the swaged designs are less expensive and easier to construct. In addition to optimizing HTIR-TC performance, This UNERI project provided unique opportunities to several University of Idaho students, allowing them to

  1. Structural Failure Condition for Bifurcated Rubble Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Hirabayashi, M.; Scheeres, D. J.

    2014-12-01

    The present study investigates the structural failure conditions of uniformly rotating bifurcated asteroids with cohesion due to a static spin-up. We apply a newly derived technique (Hirabayashi and Scheeres, submitted) that probes the failure state of an asteroid. The technique determines an upper bound condition for structural failure of a slice normal to the minimum moment of inertia axis. The detailed study of these failure modes for cohesive, rotating rubble pile asteroid is motivated by recent observations of 'active asteroids,' bodies which are seemingly disintegrating and fissioning due to their rapid spin rates (Jewitt et al. 2013, 2014; Hirabayashi et al. 2014). Figure 1 shows the shape of 4486 Mithra. We compare 3 slices, slices 1 and 3 including the knobs and slice 2 being the neck (Fig. 1), to determine a more precise condition for structural failure. Figures 2 and 3 describe the limit of friction angle with cohesion of 0 Pa and 500 Pa, respectively. The narrow solid, dashed, and dotted lines give the limits of slices 1, 2, and 3, respectively. The bold solid lines indicate the limit of the total volume, i.e., the whole volume reaching the failure point, and that of the partial volume, i.e., the most sensitive condition among the slices. The shadowed areas show the structurally stable regions. The results show that Mithra's failure locations change as a function of its spin periods and cohesion. For the cohesionless case, the knobs are more sensitive to structural failure than the neck at a spin period ranging from 3.8 hr to 4.8 hr, while the neck fails first at other spin periods. For the 500 Pa cohesion case, the limits of friction angle shift to higher spin periods. Also, at higher spin periods, we find that a lower friction angle is sometimes stronger than a higher friction angle. This comes from the fact that under constant cohesion a lower friction angle can give wider stable regions below the yield envelope. Our study reveals that there exits a

  2. Crystal Structure and Self-Organized Criticality in a Bead Pile

    NASA Astrophysics Data System (ADS)

    Baker, Elizabeth; Jacobs, D. T.

    2004-03-01

    This experiment examined a conical bead pile, crystal structures that formed in the pile, and the distribution of avalanche sizes when using uniform 3mm stainless steel beads. A bead pile is built by pouring beads onto a circular base with one layer of beads glued as a hexagonal lattice. Beads are then individually dropped from a fixed height after which the pile is massed. This process is repeated for thousands of bead drops. By measuring the number of avalanches of a given size that occurred during the experiment, the resulting distribution could be compared to a power law description as predicted by self-organized criticality. We had found in an earlier experiment that glass beads dropped from a small height were consistent with a simple power-law, but if dropped from larger heights then a power-law times an exponential was needed. The stainless steel beads always had a distribution that deviated from a simple power-law with larger deviations as the beads were dropped from larger heights. In addition, we observed crystal structures (hexagonal close packing and face-centered cubic packing) to form in the mostly amorphous pile during the experiments. These structures formed cliffs where the beads were arranged in a square pattern along their faces, with the cliffs themselves arranged around the pile in a hexagonal pattern as viewed from above. These structures did not prevent avalanches from occurring over their faces, but may have affected the avalanche distributions. We acknowledge support from NASA and from NSF-REU grant DMR 0243811.

  3. Litter use by laying hens in a commercial aviary: dust bathing and piling.

    PubMed

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    The laying hen industry, including in the United States, is responding to social concerns about hen welfare by implementing alternative housing systems such as the aviary, to provide more space and resources to large groups of hens. Data detailing the behavior of hens in commercial aviaries is needed to determine hens' use of the resources in order to understand their impact on hen welfare. The open litter area of aviaries provides additional space for hens during the day. Litter is also a substrate for dust bathing which is a strongly motivated natural behavior. Hens are often synchronous in their performance of dust bathing, which may lead to overcrowding in the litter area. Additionally, the open litter area can facilitate expression of unusual behavior such as flock piling (defined as the occurrence of densely grouped clusters of hens, resulting from no obvious cause and occurring randomly throughout the day and flock cycle) which may be a welfare concern. Therefore, we conducted observations of hen occupancy of the open litter area and the performance of dust bathing and flock piling across 3 production points (peak lay, mid lay and end of lay) for two flocks of Lohmann White laying hens housed in a commercial aviary. All areas of the open litter area were occupied to the same degree. Hens performed dust bathing throughout the day but showed peak dust bathing activity in the afternoon for Flock 1 (all P < 0.001) and in the late morning for Flock 2 (all P < 0.001). Overall, 174 incidents of piling behavior were observed between the 2 flocks, with piles varying in size, duration, and time of occurrence; however, no smothering was detected. Crowding on the open litter area sometimes occurred during peak periods of synchronous dust bathing and when hens piled. Further research is needed to understand the welfare implications of individual hen use of the open litter area and the causes and welfare implications of hen piling.

  4. H-NS suppresses pilE intragenic transcription and antigenic variation in Neisseria gonorrhoeae.

    PubMed

    Masters, Thao L; Wachter, Shaun; Wachter, Jenny; Hill, Stuart A

    2016-01-01

    Initially, pilE transcription in Neisseria gonorrhoeae appeared to be complicated, yet it was eventually simplified into a model where integration host factor activates a single -35/ -10 promoter. However, with the advent of high-throughput RNA sequencing, numerous small pil-specific RNAs (sense as well as antisense) have been identified at the pilE locus as well as at various pilS loci. Using a combination of in vitro transcription, site-directed mutagenesis, Northern analysis and quantitative reverse transcriptase PCR (qRT-PCR) analysis, we have identified three additional non-canonical promoter elements within the pilE gene; two are located within the midgene region (one sense and one antisense), with the third, an antisense promoter, located immediately downstream of the pilE ORF. Using strand-specific qRT-PCR analysis, an inverse correlation exists between the level of antisense expression and the amount of sense message. By their nature, promoter sequences tend to be AT-rich. In Escherichia coli, the small DNA-binding protein H-NS binds to AT-rich sequences and inhibits intragenic transcription. In N. gonorrhoeae hns mutants, pilE antisense transcription was increased twofold, with a concomitant decrease in sense transcript levels. However, most noticeably in these mutants, the absence of H-NS protein caused pilE/pilS recombination to increase dramatically when compared with WT values. Consequently, H-NS protein suppresses pilE intragenic transcription as well as antigenic variation through the pilE/pilS recombination system.

  5. The effect of dust emissions from open storage piles to particle ambient concentration and human exposure.

    PubMed

    Chalvatzaki, E; Aleksandropoulou, V; Glytsos, T; Lazaridis, M

    2012-12-01

    The current study focus on the determination of dust emissions from piles in open storage yards of a municipal solid waste (MSW) composting site and the subsequent atmospheric dust dispersion. The ISC3-ST (Industrial Source Complex Version 3 - Short Term) model was used for the evaluation of the PM(10) ambient concentrations associated with the dispersion of MSW compost dust emissions in air. Dust emission rates were calculated using the United States Environmental Protection Agency proposed dust resuspension formulation from open storage piles using local meteorological data. The dispersion modelling results on the spatial distribution of PM(10) source depletion showed that the maximum concentrations were observed at a distance 25-75 m downwind of the piles in the prevailing wind direction. Sensitivity calculations were performed also to reveal the effect of the compost pile height, the friction velocity and the receptor height on the ambient PM(10) concentration. It was observed that PM(10) concentrations (downwind in the prevailing wind direction) increased with increasing the friction velocity, increasing the pile height (for distances greater than 125 m from the source) and decreasing the receptor height (for distances greater than 125 m from the source). Furthermore, the results of ISC3-ST were analysed with the ExDoM (Exposure Dose Model) human exposure model. The ExDoM is a model for calculating the human exposure and the deposition dose, clearance, and finally retention of aerosol particles in the human respiratory tract (RT). PM(10) concentration at the composting site was calculated as the sum of the concentration from compost pile dust resuspension and the background concentration. It was found that the exposure to PM(10) and deposited lung dose for an adult Caucasian male who is not working at the composting site is less by 20-74% and 29-84%, respectively, compared to those for a worker exposed to PM concentrations at the composting site.

  6. Pile-up reconstruction algorithm for high count rate gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Petrovič, T.; Vencelj, M.; Lipoglavšek, M.; Novak, R.; Savran, D.

    2013-04-01

    In high count rate γ-ray spectrometry, the pile-up phenomenon turns out to be an important problem with respect to energy resolution and detection efficiency. Pile-up effects occur when two events are detected so close in time that instrumentation cannot properly extract information from both of them. Because this kind of data is incorrect and marginally useful, such data had to be rejected in traditional pulse processors. In times of digital pulse processing however, one can reconstruct piled-up pulse amplitudes by special algebraic approaches. In fully digital signal acquisition, the moving window deconvolution (MWD) method is commonly used. This method requires two parameters to be carefully set, namely the flattop time (dictated by the maximum rise time of the signal) and the shaping time, to accomplish the best possible energy resolution. In this way, the maximum energy resolution is accomplished, but a lot of piled-up events are rejected, reducing detection efficiency. We propose a method that restores some of the pile-up events, using a parallel block MWD implementation where the shaping time parameter differs for every MWD block. Careful detection of as many true events as possible, as well as determining their exact occurrence in time (their respective timestamps) is the key in getting the most out of the measured signal. With proper analysis logic we get more experimental information through reduced dead time, at the cost of controlled and selectively worsened energy resolution, on an event-by-event basis, achieving better overall detection efficiency. This method was tested on real experimental data where the detection efficiency of our method is higher, by a factor of 4.4(9), than the efficiency of a standard method with pile-up rejection at 500 kcps count rate.

  7. Prediction of AMD generation potential in mining waste piles, in the Sarcheshmeh porphyry copper deposit, Iran.

    PubMed

    Modabberi, Soroush; Alizadegan, Ali; Mirnejad, Hassan; Esmaeilzadeh, Esmat

    2013-11-01

    This study investigates the possibility of acid mine drainage (AMD) generation in active and derelict mine waste piles in Sarcheshmeh Copper Mine produced in several decades, using static tests including acid-base accounting (ABA) and net acid-generating pH (NAGpH). In this study, 51 composite samples were taken from 11 waste heaps, and static ABA and NAGpH tests were carried out on samples. While some piles are acid producing at present and AMD is discharging from the piles, most of them do not show any indication on their AMD potential, and they were investigated to define their acid-producing potential. The analysis of data indicates that eight waste piles are potentially acid generating with net neutralization potentials (NNPs) of -56.18 to -199.3, net acid generating of 2.19-3.31, and NPRs from 0.18 to 0.44. Other waste piles exhibited either a very low sulfur, high carbonate content or excess carbonate over sulfur; hence, they are not capable of acid production or they can be considered as weak acid producers. Consistency between results of ABA and NAGpH tests using a variety of classification criteria validates these tests as powerful means for preliminary evaluation of AMD/ARD possibilities in any mining district. It is also concluded that some of the piles with very negative NNPs are capable to produce AMD naturally, and they can be used in heap leaching process for economic recovery of trace amounts of metals without applying any biostimulation methods. PMID:23813094

  8. Litter use by laying hens in a commercial aviary: dust bathing and piling.

    PubMed

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    The laying hen industry, including in the United States, is responding to social concerns about hen welfare by implementing alternative housing systems such as the aviary, to provide more space and resources to large groups of hens. Data detailing the behavior of hens in commercial aviaries is needed to determine hens' use of the resources in order to understand their impact on hen welfare. The open litter area of aviaries provides additional space for hens during the day. Litter is also a substrate for dust bathing which is a strongly motivated natural behavior. Hens are often synchronous in their performance of dust bathing, which may lead to overcrowding in the litter area. Additionally, the open litter area can facilitate expression of unusual behavior such as flock piling (defined as the occurrence of densely grouped clusters of hens, resulting from no obvious cause and occurring randomly throughout the day and flock cycle) which may be a welfare concern. Therefore, we conducted observations of hen occupancy of the open litter area and the performance of dust bathing and flock piling across 3 production points (peak lay, mid lay and end of lay) for two flocks of Lohmann White laying hens housed in a commercial aviary. All areas of the open litter area were occupied to the same degree. Hens performed dust bathing throughout the day but showed peak dust bathing activity in the afternoon for Flock 1 (all P < 0.001) and in the late morning for Flock 2 (all P < 0.001). Overall, 174 incidents of piling behavior were observed between the 2 flocks, with piles varying in size, duration, and time of occurrence; however, no smothering was detected. Crowding on the open litter area sometimes occurred during peak periods of synchronous dust bathing and when hens piled. Further research is needed to understand the welfare implications of individual hen use of the open litter area and the causes and welfare implications of hen piling. PMID:26354762

  9. Study on load-bearing characteristics of a new pile group foundation for an offshore wind turbine.

    PubMed

    Lang, Ruiqing; Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect. PMID:25250375

  10. Study on Load-Bearing Characteristics of a New Pile Group Foundation for an Offshore Wind Turbine

    PubMed Central

    Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect. PMID:25250375

  11. Study on load-bearing characteristics of a new pile group foundation for an offshore wind turbine.

    PubMed

    Lang, Ruiqing; Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect.

  12. Acoustic Response to Playback of Pile-Driving Sounds by Snapping Shrimp.

    PubMed

    Spiga, Ilaria

    2016-01-01

    There is concern about the effects of noise from impact pile driving as this constructional technique becomes increasingly widespread in coastal areas. The habitats of most marine invertebrate species are likely to overlap with the areas of human activities along the coast and be affected by the increased levels of noise produced. This paper investigates the acoustic response of chorusing snapping shrimp to different sound pressure levels. A significant increase in the snap number and snap amplitude was recorded during the playback of piling noise, suggesting that noise exposure affected the acoustic behavior of these animals.

  13. SIMULATING ASTEROID RUBBLE PILES WITH A SELF-GRAVITATING SOFT-SPHERE DISTINCT ELEMENT METHOD MODEL

    SciTech Connect

    Sanchez, Paul; Scheeres, Daniel J.

    2011-02-01

    This paper applies a soft-sphere distinct element method Granular Dynamics code to simulate asteroid regolith and rubble piles. Applications to regolith studies in low gravity are also studied. Then an algorithm to calculate self-gravity is derived and incorporated for full-scale simulations of rubble-pile asteroids using Granular Dynamics techniques. To test its validity, the algorithm's results are compared with the exact direct calculation of the gravitational forces. Further avenues to improve the performance of the algorithm are also discussed.

  14. Pile Driving at the New Bridge at Tappan Zee: Potential Environmental Impacts.

    PubMed

    Popper, Arthur N; Moese, Mark; Rollino, John; Krebs, Justin; Racca, Roberto; Martin, Bruce; Zeddies, David; MacGillivray, Alexander; Jacobs, Fred

    2016-01-01

    A new bridge will be constructed to replace the aging Tappan Zee Bridge over the Hudson River in New York. Construction will potentially result in hydroacoustic impacts to the local fish fauna. As a consequence, a substantial environmental impact analysis had to be conducted to obtain construction permits. This paper describes the process of environmental analysis and some of the results of the studies that led up to the final permitting. The process included modeling of pile-driving acoustics, analysis of river ambient noise, analysis of test piling, and observations on fish behavior during these tests.

  15. Noise Mitigation During Pile Driving Efficiently Reduces Disturbance of Marine Mammals.

    PubMed

    Nehls, Georg; Rose, Armin; Diederichs, Ansgar; Bellmann, Michael; Pehlke, Hendrik

    2016-01-01

    Acoustic monitoring of harbor porpoises (Phocoena phocoena L., 1758) indicated a strongly reduced disturbance by noise emitted by pile driving for offshore wind turbine foundations insulated by a big bubble curtain (BBC). This newly developed noise mitigation system was tested during construction of the offshore wind farm Borkum West II (North Sea). Because porpoise activity strongly corresponded to the sound level, operation of the new system under its most suitable configuration reduced the porpoise disturbance area by ~90%. Hence, for the first time, a positive effect of a noise mitigation system during offshore pile driving on an affected marine mammal species could be demonstrated.

  16. Noise Mitigation During Pile Driving Efficiently Reduces Disturbance of Marine Mammals.

    PubMed

    Nehls, Georg; Rose, Armin; Diederichs, Ansgar; Bellmann, Michael; Pehlke, Hendrik

    2016-01-01

    Acoustic monitoring of harbor porpoises (Phocoena phocoena L., 1758) indicated a strongly reduced disturbance by noise emitted by pile driving for offshore wind turbine foundations insulated by a big bubble curtain (BBC). This newly developed noise mitigation system was tested during construction of the offshore wind farm Borkum West II (North Sea). Because porpoise activity strongly corresponded to the sound level, operation of the new system under its most suitable configuration reduced the porpoise disturbance area by ~90%. Hence, for the first time, a positive effect of a noise mitigation system during offshore pile driving on an affected marine mammal species could be demonstrated. PMID:26611029

  17. Rubble-Pile Minor Planet Sylvia and Her Twins

    NASA Astrophysics Data System (ADS)

    2005-08-01

    from a primordial asteroid. "It could be up to 60 percent empty space," said co-discoverer Daniel Hestroffer (Observatoire de Paris, France). "It is most probably a "rubble-pile" asteroid", Marchis added. These asteroids are loose aggregations of rock, presumably the result of a collision. Two asteroids smacked into each other and got disrupted. The new rubble-pile asteroid formed later by accumulation of large fragments while the moonlets are probably debris left over from the collision that were captured by the newly formed asteroid and eventually settled into orbits around it. "Because of the way they form, we expect to see more multiple asteroid systems like this." Marchis and his colleagues will report their discovery in the August 11 issue of the journal Nature, simultaneously with an announcement that day at the Asteroid Comet Meteor conference in Armação dos Búzios, Rio de Janeiro state, Brazil.

  18. APPLICATION OF STEEL PIPE PILE LOADING TESTS TO DESIGN VERIFICATION OF FOUNDATION OF THE TOKYO GATE BRIDGE

    NASA Astrophysics Data System (ADS)

    Saitou, Yutaka; Kikuchi, Yoshiaki; Kusakabe, Osamu; Kiyomiya, Osamu; Yoneyama, Haruo; Kawakami, Taiji

    Steel sheet pipe pile foundations with large diameter steel pipe sheet pile were used for the foundation of the main pier of the Tokyo Gateway bridge. However, as for the large diameter steel pipe pile, the bearing mechanism including a pile tip plugging effect is still unclear due to lack of the practical examinations even though loading tests are performed on Trans-Tokyo Bay Highway. In the light of the foregoing problems, static pile loading tests both vertical and horizontal directions, a dynamic loading test, and cone penetration tests we re conducted for determining proper design parameters of the ground for the foundations. Design parameters were determined rationally based on the tests results. Rational design verification was obtained from this research.

  19. Avoidance of Pile-Driving Noise by Hudson River Sturgeon During Construction of the New NY Bridge at Tappan Zee.

    PubMed

    Krebs, Justin; Jacobs, Fred; Popper, Arthur N

    2016-01-01

    Sturgeon movements were monitored during a pile-driving operation. Fewer sturgeon were detected during pile driving and remained for a shorter time than during silent control periods. Moreover, the short time spent by sturgeon near pile driving suggests that they were unlikely to have reached the criterion of 187 dB re 1 μPa(2)·s cumulative sound exposure level. These results suggest that sturgeon are likely to avoid impact pile driving and not remain long enough to experience physiological effects, thus providing empirical evidence that the 206 dB re 1 μPa peak sound pressure level is the appropriate criterion for assessing the impacts of pile-driving noise on sturgeon.

  20. Etude des Abondances de MG et de fe dans la Composante Stellaire des Disques des Galaxies Spirales

    NASA Astrophysics Data System (ADS)

    Beauchamp, Dominique

    Je presente ici une technique d'observation par imagerie des disques stellaires des galaxies spirales. Je tente, a l'aide d'un modele evolutif multiphase, de determiner les abondances de fer et de magnesium dans les disques. Dans ce but, je mesure les indices Mg2 et Fe5270 du systeme de Lick. Ces elements representent un choix judicieux d'indicateurs car ils sont formes par des supernovae de deux types differents ayant des durees de vie differentes. Le rapport d'abondances de ces deux elements est un indicateur du taux de formation des populations stellaires. Je decris, en premier lieu, les observations, la technique de mesure, ainsi que son application. J'analyse ensuite les indices mesures. A partir du modele multiphase, j'explore differents parametres physiques des spirales comme le taux de formation stellaire, l'evolution des abondances, les effets possibles de la presence de la barre, etc.

  1. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  2. Classification of 8 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    King, A.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; OâNeill, C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  3. Classification of 13 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Sommer, N.; Tucker, B. E.; Moller, A.; Zhang, B.; Macualay, E.; Lidman, C.; Gshwend, J.; Martini, P.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  4. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  5. Classification of 2 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    O'Neill, C. R.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Gupta, R.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.

    2016-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  6. An enhanced compost temperature sampling framework: case study of a covered aerated static pile.

    PubMed

    Isobaev, Pulat; Bouferguene, Ahmed; Wichuk, Kristine M; McCartney, Daryl

    2014-07-01

    Spatial and temporal temperature variations exist in a compost pile. This study demonstrates that systematic temperature sampling of a compost pile, as is widely done, tends to underestimate these variations, which in turn may lead to false conclusions about the sanitary condition of the final product. To address these variations, a proper scheme of temperature sampling needs to be used. A comparison of the results from 21 temperature data loggers randomly introduced into a compost pile with those from 20 systematically introduced data loggers showed that the mean, maximum and minimum temperatures in both methods were very similar in their magnitudes. Overall, greater temperature variation was captured using the random method. In addition, 95% of the probes introduced systematically had attained thermophilic sanitation conditions (≥ 55°C for three consecutive days), as compared to 76% from the group that were randomly introduced. Furthermore, it was found that, from a statistical standpoint, readings from at least 47 randomly introduced temperature loggers are necessary to capture the observed temperature variation. Lastly, the turning of the compost pile was found to increase the chance that any random particle would be exposed to the temperature ≥ 55°C for three consecutive days. One turning was done during the study, and it increased the probability from 76% to nearly 85%. Using the Markov chain model it was calculated that if five turnings had been implemented on the evaluated technology, the likelihood that every particle would experience the required time-temperature condition would be 98%. PMID:24767412

  7. Effects of exposure to pile driving sounds on fish inner ear tissues.

    PubMed

    Casper, Brandon M; Smith, Michael E; Halvorsen, Michele B; Sun, Huifang; Carlson, Thomas J; Popper, Arthur N

    2013-10-01

    Impulsive pile driving sound can cause injury to fishes, but no studies to date have examined whether such injuries include damage to sensory hair cells in the ear. Possible effects on hair cells were tested using a specially designed wave tube to expose two species, hybrid striped bass (white bass Morone chrysops × striped bass Morone saxatilis) and Mozambique tilapia (Oreochromis mossambicus), to pile driving sounds. Fish were exposed to 960 pile driving strikes at one of three treatment levels: 216, 213, or 210dB re 1 μPa(2)·s cumulative Sound Exposure Level. Both hybrid striped bass and tilapia exhibited barotraumas such as swim bladder ruptures, herniations, and hematomas to several organs. Hybrid striped bass exposed to the highest sound level had significant numbers of damaged hair cells, while no damage was found when fish were exposed at lower sound levels. Considerable hair cell damage was found in only one out of 11 tilapia specimens exposed at the highest sound level. Results suggest that impulsive sounds such as from pile driving may have a more significant effect on the swim bladders and surrounding organs than on the inner ears of fishes, at least at the sound exposure levels used in this study.

  8. ACTIV: Sandwich Detector Activity from In-Pile Slowing-Down Spectra Experiment

    SciTech Connect

    2013-08-01

    ACTIV calculates the activities of a sandwich detector, to be used for in-pile measurements in slowing-down spectra below a few keV. The effect of scattering with energy degradation in the filter and in the detectors has been included to a first approximation.

  9. Effects of exposure to pile driving sounds on fish inner ear tissues.

    PubMed

    Casper, Brandon M; Smith, Michael E; Halvorsen, Michele B; Sun, Huifang; Carlson, Thomas J; Popper, Arthur N

    2013-10-01

    Impulsive pile driving sound can cause injury to fishes, but no studies to date have examined whether such injuries include damage to sensory hair cells in the ear. Possible effects on hair cells were tested using a specially designed wave tube to expose two species, hybrid striped bass (white bass Morone chrysops × striped bass Morone saxatilis) and Mozambique tilapia (Oreochromis mossambicus), to pile driving sounds. Fish were exposed to 960 pile driving strikes at one of three treatment levels: 216, 213, or 210dB re 1 μPa(2)·s cumulative Sound Exposure Level. Both hybrid striped bass and tilapia exhibited barotraumas such as swim bladder ruptures, herniations, and hematomas to several organs. Hybrid striped bass exposed to the highest sound level had significant numbers of damaged hair cells, while no damage was found when fish were exposed at lower sound levels. Considerable hair cell damage was found in only one out of 11 tilapia specimens exposed at the highest sound level. Results suggest that impulsive sounds such as from pile driving may have a more significant effect on the swim bladders and surrounding organs than on the inner ears of fishes, at least at the sound exposure levels used in this study. PMID:23850719

  10. Use of a magnetic field to modify and detect avalanche behavior on a conical bead pile

    NASA Astrophysics Data System (ADS)

    Johnson, Nathan; Lehman, Susan

    2015-03-01

    A conical bead pile subject to slow driving and an external magnetic field is used to test the effects of drop height and cohesion on avalanche statistics. Magnetically susceptible beads were dropped onto a pile from different heights and into different strengths of magnetic field. Avalanches were recorded by the change in mass as beads fall off the pile. For beads dropped from a low drop height with no cohesion, the avalanche size distribution follows a power law. As cohesion increases, we observe an increase in the probability of very large avalanches and decreases in the mid-size avalanches. The resulting bump in the avalanche distribution moves to larger avalanche size as the cohesion in the system is increased, matching the prediction by an analytic theory from a mean-field model of slip avalanches. The model also makes predictions for avalanche duration, which is not measurable with our current system. Since the steel beads are magnetized while in the applied magnetic field, their motion during an avalanche creates a change in magnetic flux. To detect this motion, we have placed a large-diameter pick-up coil around the pile. Results of the testing and calibration of this coil to measure avalanche duration are presented.

  11. FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery

    PubMed Central

    Haselman, M. D.; Pasko, J.; Hauck, S.; Lewellen, T. K.; Miyaoka, R. S.

    2013-01-01

    Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz. This, combined with FPGA’s low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilized to add significant signal processing power to produce higher quality images. In this paper we report on an all-digital pulse pile-up correction algorithm that has been developed for the FPGA. The pile-up mitigation algorithm will allow the scanner to run at higher count rates without incurring large data losses due to the overlapping of scintillation signals. This correction technique utilizes a reference pulse to extract timing and energy information for most pile-up events. Using pulses acquired from a Zecotech Photonics MAPD-N with an LFS-3 scintillator, we show that good timing and energy information can be achieved in the presence of pile-up utilizing a moderate amount of FPGA resources. PMID:24265508

  12. 40 CFR 270.18 - Specific part B information requirements for waste piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... complied with or detailed plans and an engineering report describing how the requirements of § 264.90(b)(2) will be met. (c) Detailed plans and an engineering report describing how the waste pile is designed and...(b) of this chapter, submit detailed plans, and engineering and hydrogeological reports,...

  13. FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery.

    PubMed

    Haselman, M D; Pasko, J; Hauck, S; Lewellen, T K; Miyaoka, R S

    2012-10-01

    Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz. This, combined with FPGA's low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilized to add significant signal processing power to produce higher quality images. In this paper we report on an all-digital pulse pile-up correction algorithm that has been developed for the FPGA. The pile-up mitigation algorithm will allow the scanner to run at higher count rates without incurring large data losses due to the overlapping of scintillation signals. This correction technique utilizes a reference pulse to extract timing and energy information for most pile-up events. Using pulses acquired from a Zecotech Photonics MAPD-N with an LFS-3 scintillator, we show that good timing and energy information can be achieved in the presence of pile-up utilizing a moderate amount of FPGA resources. PMID:24265508

  14. 77 FR 43259 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving for Honolulu Seawater...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-24

    ... beaked whale 2,872 Year round (Mesoplodon densirostris). Blue whale (Balaenoptera musculus).. n/a Winter...). Monk seal (Monachus schauinslandi).. 1,161 Year round Endangered. ] Blue whales and killer whales are... November 2012 or April 2013 in order to avoid the peak humpback whale season. The production piles would...

  15. Brazilian uranium mine decommissioning-chemical and radiological study of waste rock piles

    SciTech Connect

    Wiikmann, L. O.

    1996-12-31

    The Pocos de Caldas plateau is a high-natural-radioactivity area in the state of Minas Gerais, southeast Brazil. Uranium occurrence in the plateau was first observed in 1948. Mining started in 1977 with mine scouring, and the first ore pile was constructed in 1981. Waste rocks are derived from the mine material. The analysis of core samples is discussed.

  16. FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery.

    PubMed

    Haselman, M D; Pasko, J; Hauck, S; Lewellen, T K; Miyaoka, R S

    2012-10-01

    Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz. This, combined with FPGA's low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilized to add significant signal processing power to produce higher quality images. In this paper we report on an all-digital pulse pile-up correction algorithm that has been developed for the FPGA. The pile-up mitigation algorithm will allow the scanner to run at higher count rates without incurring large data losses due to the overlapping of scintillation signals. This correction technique utilizes a reference pulse to extract timing and energy information for most pile-up events. Using pulses acquired from a Zecotech Photonics MAPD-N with an LFS-3 scintillator, we show that good timing and energy information can be achieved in the presence of pile-up utilizing a moderate amount of FPGA resources.

  17. 75 FR 48941 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ... reactions with the second and third highest causes being canoes and kayaks, respectively. The scientists.... However, sudden presence of a disturbance source (e.g., kayaker) can induce strong behavioral reactions. To avoid inducing strong reactions, the WA DNR would conduct activities such that the piles...

  18. 77 FR 14736 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for Fishermen's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ... radius buffer zone around the proposed turbine locations. A total of 389 transects were surveyed totaling... measures to minimize adverse impacts to marine mammals: Exclusion Zone The purpose of an exclusion zone is... establish a preliminary 1,000-m exclusion zone around each pile driving site, based on the estimated...

  19. Pulse pile-up in hard X-ray detector systems. [for solar X-rays

    NASA Technical Reports Server (NTRS)

    Datlowe, D. W.

    1975-01-01

    When pulse-height spectra are measured by a nuclear detection system at high counting rates, the probability that two or more pulses will arrive within the resolving time of the system is significant. This phenomenon, pulse pile-up, distorts the pulse-height spectrum and must be considered in the interpretation of spectra taken at high counting rates. A computational technique for the simulation of pile-up is developed. The model is examined in the three regimes where (1) the time between pulses is long compared to the detector-system resolving time, (2) the time between pulses is comparable to the resolving time, and (3) many pulses occur within the resolving time. The technique is used to model the solar hard X-ray experiment on the OSO-7 satellite; comparison of the model with data taken during three large flares shows excellent agreement. The paper also describes rule-of-thumb tests for pile-up and identifies the important detector design factors for minimizing pile-up, i.e., thick entrance windows and short resolving times in the system electronics.

  20. Recovery of Barotrauma Injuries in Chinook Salmon, Oncorhynchus tshawytscha from Exposure to Pile Driving Sound

    PubMed Central

    Casper, Brandon M.; Popper, Arthur N.; Matthews, Frazer; Carlson, Thomas J.; Halvorsen, Michele B.

    2012-01-01

    Juvenile Chinook salmon, Oncorhynchus tshawytscha, were exposed to simulated high intensity pile driving signals to evaluate their ability to recover from barotrauma injuries. Fish were exposed to one of two cumulative sound exposure levels for 960 pile strikes (217 or 210 dB re 1 µPa2·s SELcum; single strike sound exposure levels of 187 or 180 dB re 1 µPa2⋅s SELss respectively). This was followed by an immediate assessment of injuries, or assessment 2, 5, or 10 days post-exposure. There were no observed mortalities from the pile driving sound exposure. Fish exposed to 217 dB re 1 µPa2·s SELcum displayed evidence of healing from injuries as post-exposure time increased. Fish exposed to 210 dB re 1 µPa2·s SELcum sustained minimal injuries that were not significantly different from control fish at days 0, 2, and 10. The exposure to 210 dB re 1 µPa2·s SELcum replicated the findings in a previous study that defined this level as the threshold for onset of injury. Furthermore, these data support the hypothesis that one or two Mild injuries resulting from pile driving exposure are unlikely to affect the survival of the exposed animals, at least in a laboratory environment. PMID:22745794

  1. Sigma factor RpoN (σ54) regulates pilE transcription in commensal Neisseria elongata.

    PubMed

    Rendón, María A; Hockenberry, Alyson M; McManus, Steven A; So, Magdalene

    2013-10-01

    Human-adapted Neisseria includes two pathogens, Neisseria gonorrhoeae and Neisseria meningitidis, and at least 13 species of commensals that colonize many of the same niches as the pathogens. The Type IV pilus plays an important role in the biology of pathogenic Neisseria. In these species, Sigma factor RpoD (σ(70)), Integration Host Factor, and repressors RegF and CrgA regulate transcription of pilE, the gene encoding the pilus structural subunit. The Type IV pilus is also a strictly conserved trait in commensal Neisseria. We present evidence that a different mechanism regulates pilE transcription in commensals. Using Neisseria elongata as a model, we show that Sigma factor RpoN (σ(54)), Integration Host Factor, and an activator we name Npa regulate pilE transcription. Taken in context with previous reports, our findings indicate pilE regulation switched from an RpoN- to an RpoD-dependent mechanism as pathogenic Neisseria diverged from commensals during evolution. Our findings have implications for the timing of Tfp expression and Tfp-mediated host cell interactions in these two groups of bacteria. PMID:23899162

  2. 30 CFR 784.16 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., and refuse piles. (a) General. Each application must include a general plan and a detailed design plan... and geologic information required to assess the hydrologic impact of the structure; (iv) Contain a... certification statement which includes a schedule setting forth the dates when any detailed design plans...

  3. 40 CFR 411.30 - Applicability; description of the materials storage piles runoff subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... products, finished products and waste materials which are used in or derived from the manufacture of cement... materials storage piles runoff subcategory. 411.30 Section 411.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CEMENT MANUFACTURING POINT SOURCE...

  4. 40 CFR 270.18 - Specific part B information requirements for waste piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... complied with; (h) A description of how hazardous waste residues and contaminated materials will be removed... requirements for waste piles. 270.18 Section 270.18 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) EPA ADMINISTERED PERMIT PROGRAMS: THE HAZARDOUS WASTE PERMIT...

  5. Comparison of Numerical Analyses with a Static Load Test of a Continuous Flight Auger Pile

    NASA Astrophysics Data System (ADS)

    Hoľko, Michal; Stacho, Jakub

    2014-12-01

    The article deals with numerical analyses of a Continuous Flight Auger (CFA) pile. The analyses include a comparison of calculated and measured load-settlement curves as well as a comparison of the load distribution over a pile's length. The numerical analyses were executed using two types of software, i.e., Ansys and Plaxis, which are based on FEM calculations. Both types of software are different from each other in the way they create numerical models, model the interface between the pile and soil, and use constitutive material models. The analyses have been prepared in the form of a parametric study, where the method of modelling the interface and the material models of the soil are compared and analysed. Our analyses show that both types of software permit the modelling of pile foundations. The Plaxis software uses advanced material models as well as the modelling of the impact of groundwater or overconsolidation. The load-settlement curve calculated using Plaxis is equal to the results of a static load test with a more than 95 % degree of accuracy. In comparison, the load-settlement curve calculated using Ansys allows for the obtaining of only an approximate estimate, but the software allows for the common modelling of large structure systems together with a foundation system.

  6. Validation of finite element computations for the quantitative prediction of underwater noise from impact pile driving.

    PubMed

    Zampolli, Mario; Nijhof, Marten J J; de Jong, Christ A F; Ainslie, Michael A; Jansen, Erwin H W; Quesson, Benoit A J

    2013-01-01

    The acoustic radiation from a pile being driven into the sediment by a sequence of hammer strikes is studied with a linear, axisymmetric, structural acoustic frequency domain finite element model. Each hammer strike results in an impulsive sound that is emitted from the pile and then propagated in the shallow water waveguide. Measurements from accelerometers mounted on the head of a test pile and from hydrophones deployed in the water are used to validate the model results. Transfer functions between the force input at the top of the anvil and field quantities, such as acceleration components in the structure or pressure in the fluid, are computed with the model. These transfer functions are validated using accelerometer or hydrophone measurements to infer the structural forcing. A modeled hammer forcing pulse is used in the successive step to produce quantitative predictions of sound exposure at the hydrophones. The comparison between the model and the measurements shows that, although several simplifying assumptions were made, useful predictions of noise levels based on linear structural acoustic models are possible. In the final part of the paper, the model is used to characterize the pile as an acoustic radiator by analyzing the flow of acoustic energy.

  7. 30 CFR 784.16 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... analysis of alternatives for the proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  8. 30 CFR 784.16 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... analysis of alternatives for the proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  9. 30 CFR 780.25 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean Water Act requirements, you may... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  10. 30 CFR 780.25 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean Water Act requirements, you may... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  11. 30 CFR 780.25 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean Water Act requirements, you may... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  12. 30 CFR 784.16 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... analysis of alternatives for the proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  13. 30 CFR 784.16 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... analysis of alternatives for the proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  14. 30 CFR 780.25 - Reclamation plan: Siltation structures, impoundments, and refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....C. 552(a) and 1 CFR part 51. You may review and download the incorporated document from the Natural... proposed impoundment or refuse pile under 40 CFR 230.10 to meet Clean Water Act requirements, you may... related fields such as geology, land surveying, and landscape architecture; (B) Include any...

  15. Validation of finite element computations for the quantitative prediction of underwater noise from impact pile driving.

    PubMed

    Zampolli, Mario; Nijhof, Marten J J; de Jong, Christ A F; Ainslie, Michael A; Jansen, Erwin H W; Quesson, Benoit A J

    2013-01-01

    The acoustic radiation from a pile being driven into the sediment by a sequence of hammer strikes is studied with a linear, axisymmetric, structural acoustic frequency domain finite element model. Each hammer strike results in an impulsive sound that is emitted from the pile and then propagated in the shallow water waveguide. Measurements from accelerometers mounted on the head of a test pile and from hydrophones deployed in the water are used to validate the model results. Transfer functions between the force input at the top of the anvil and field quantities, such as acceleration components in the structure or pressure in the fluid, are computed with the model. These transfer functions are validated using accelerometer or hydrophone measurements to infer the structural forcing. A modeled hammer forcing pulse is used in the successive step to produce quantitative predictions of sound exposure at the hydrophones. The comparison between the model and the measurements shows that, although several simplifying assumptions were made, useful predictions of noise levels based on linear structural acoustic models are possible. In the final part of the paper, the model is used to characterize the pile as an acoustic radiator by analyzing the flow of acoustic energy. PMID:23297884

  16. NEET In-Pile Ultrasonic Sensor Enablement-FY 2012 Status Report

    SciTech Connect

    JE Daw; JL Rempe; BR Tittmann; B Reinhardt; P Ramuhalli; R Montgomery; HT Chien

    2012-09-01

    Several Department Of Energy-Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials when irradiated. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive. Ultrasonic technologies offer the potential to measure a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes, under harsh irradiation test conditions. There are two primary issues associated with in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. Due to the harsh nature of in-pile testing, and the range of measurements that are desired, an enhanced signal processing capability is needed to make in-pile ultrasonic sensors viable. This project addresses these technology deployment issues.

  17. Sigma factor RpoN (σ54) regulates pilE transcription in commensal Neisseria elongata.

    PubMed

    Rendón, María A; Hockenberry, Alyson M; McManus, Steven A; So, Magdalene

    2013-10-01

    Human-adapted Neisseria includes two pathogens, Neisseria gonorrhoeae and Neisseria meningitidis, and at least 13 species of commensals that colonize many of the same niches as the pathogens. The Type IV pilus plays an important role in the biology of pathogenic Neisseria. In these species, Sigma factor RpoD (σ(70)), Integration Host Factor, and repressors RegF and CrgA regulate transcription of pilE, the gene encoding the pilus structural subunit. The Type IV pilus is also a strictly conserved trait in commensal Neisseria. We present evidence that a different mechanism regulates pilE transcription in commensals. Using Neisseria elongata as a model, we show that Sigma factor RpoN (σ(54)), Integration Host Factor, and an activator we name Npa regulate pilE transcription. Taken in context with previous reports, our findings indicate pilE regulation switched from an RpoN- to an RpoD-dependent mechanism as pathogenic Neisseria diverged from commensals during evolution. Our findings have implications for the timing of Tfp expression and Tfp-mediated host cell interactions in these two groups of bacteria.

  18. What might rice piles tell us about non-local sediment transport?

    NASA Astrophysics Data System (ADS)

    Longjas, A.; Voller, V. R.; Paola, C.; Filipovitch, N.

    2014-12-01

    Our research objective is to identify sediment transport systems that exhibit non local signals, such as those seen in the long-profile of fluvial surfaces. In previous work we have shown that appropriate nonlocal models of sediment transport under various tectonic forcing, can lead to fluvial surface shapes that are distinct from those obtained with local models. For example, in the study of a sediment bypass system, a nonlocal model for the sediment flux predicts a concave down fluvial surface in contrast to the linear surface predicted with a local flux model. It is well known that hold ups and fast paths in transport systems lead to non-local behaviors. And we think that the mechanism that creates the unexpected curvatures in fluvial profiles is one of "storage and release". Perhaps the classic storage and release system is that seen in rice pile experiments. One set up for this experiment involves the formation of a rice pile in the gap (~25mm) between two vertical glass plates resting on a solid surface. In this system rice is added at a constant rate at the left and allowed to freely exit a distance (~0.5m) downstream; the system is run until a steady state is approached. Of course, an exact steady state is not reached because the rice does not move steadily down the pile surface but rather advances in a series of avalanches, with multiple length scales, separated by waiting times; in other words is transported via storage and release. The naive expectancy is that at the steady state the surface of the rice pile will exhibit a constant angle of repose. Our experiments with the system, however, indicate that while the storage and release mechanism invokes large temporal fluctuations in the pile its surface exhibits a persistent concave down shape. In this paper, we present the main findings of our rice pile experiment, explore models that might explain the persistence of the curved surface, and uncover the behavioral links between the rice pile model and non

  19. L'astronomie des Anciens

    NASA Astrophysics Data System (ADS)

    Nazé, Yaël

    2009-04-01

    Quelle que soit la civilisation à laquelle il appartient, l'être humain cherche dans le ciel des réponses aux questions qu'il se pose sur son origine, son avenir et sa finalité. Le premier mérite de ce livre est de nous rappeler que l'astronomie a commencé ainsi à travers les mythes célestes imaginés par les Anciens pour expliquer l'ordre du monde et la place qu'ils y occupaient. Mais les savoirs astronomiques passés étaient loin d'être négligeables et certainement pas limités aux seuls travaux des Grecs : c'est ce que l'auteur montre à travers une passionnante enquête, de Stonehenge à Gizeh en passant par Pékin et Mexico, fondée sur l'étude des monuments anciens et des sources écrites encore accessibles. Les tablettes mésopotamiennes, les annales chinoises, les chroniques médiévales, etc. sont en outre d'une singulière utilité pour les astronomes modernes : comment sinon remonter aux variations de la durée du jour au cours des siècles, ou percer la nature de l'explosion qui a frappé tant d'observateurs en 1054 ? Ce livre offre un voyage magnifiquement illustré à travers les âges, entre astronomie et archéologie.

  20. Role of rock texture and mineralogy on the hydrology and geochemistry of three neutral-drainage mesoscale experimental waste rock piles at the Antamina Mine, Peru

    NASA Astrophysics Data System (ADS)

    Peterson, H.; Bay, D. S.; Beckie, R. D.; Mayer, K. U.; Klein, B.; Smith, L.

    2009-12-01

    An ongoing study at the Antamina Cu-Zn-Mo mine in Peru investigates the hydrology and geochemistry of heterogeneous waste rock at multiple scales. Three of five instrumented mesoscale experimental waste rock piles (36m X 36m X 10m high) were constructed between 2006 and 2008. The coarsest-grained Pile 1 exhibits rapid, intense response to rain and returns to residual saturation relatively quickly, suggesting a significant influence of preferential flow in addition to high-conductivity matrix flow. Pile 2, the finest-grained of the three piles, exhibits signals from rain events that are significantly delayed and muted in comparison to those from Pile 1. Except for in the finest size fractions, the particle size distribution of Pile 3 closely resembles that of Pile 2, yet Pile 3 responds to rain events more similarly to Pile 1 than Pile 2. The presence of large boulders in Pile 3 could facilitate preferential flow, either through surface flow effects across boulders or by contributing to the formation of unfilled void space acting as macropores at high infiltration rates. The rapid rain event response of Pile 3 could also be attributed to a silt-clay percentage that is similar to Pile 1, which is less than half of the silt-clay percentage observed in Pile 2 (i.e., ~3%, ~8.5%, and ~4% for Piles 1, 2 and 3, respectively). For each of the three piles, the pH of effluent collected from bottom lysimeters and internal pore water sampled with suction lysimeters has remained circumneutral, with notable maximum concentrations of 2.8 mg/L Zn from Pile 1, which is comprised of slightly reactive hornfels and marble waste rock; 13.4 mg/L Zn and 22.7 mg/L Mo from Pile 2, comprised of reactive intrusive waste rock; and 42.5 mg/L Zn from Pile 3, comprised of reactive exoskarn waste rock. Ongoing work includes analysis of two additional mixed-rock experimental piles, studies to investigate the role of microbes on metal release (Dockrey et al., this session), analysis of pore gas

  1. 'Shrink' losses in commercially sized corn silage piles: Quantifying total losses and where they occur.

    PubMed

    Robinson, P H; Swanepoel, N; Heguy, J M; Price, T; Meyer, D M

    2016-01-15

    Silage 'shrink' (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term 'shrink' is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90±17, 68±18 and 28±21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses ('older' silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face.

  2. Hot Wire Needle Probe for In-Pile Thermal Conductivity Detection

    SciTech Connect

    Joshua Daw; Joy Rempe; Keith Condie; Darrell Knudson; S. Curtis Wilkins; Brandon S. Fox; Heng Ban

    2001-11-01

    Thermal conductivity is a key property of interest for both nuclear fuel and structural materials, and must be known for proper design, test, and application of new fuels and structural materials in nuclear reactors. Thermal conductivity is highly dependent on the physical structure, chemical composition, and the state of the material. Typically, thermal conductivity changes that occur during irradiation are measured out-of-pile by Post Irradiated Examination (PIE) using a “cook and look” approach in hot-cells. Repeatedly removing samples from a test reactor to make out-of-pile measurements is expensive, has the potential to disturb phenomena of interest, and only provides understanding of the sample's end state at the time each measurement is made. There are also limited thermophysical property data for advanced fuels. Such data are needed for simulation design codes, the development of next generation reactors, and advanced fuels for existing nuclear plants. Being able to quickly characterize fuel thermal conductivity during irradiation can improve the fidelity of data, reduce costs of post-irradiation examinations, increase understanding of how fuels behave under irradiation, and confirm or improve existing thermal conductivity measurement techniques. This paper discusses advancements from Idaho National Laboratory (INL) / Utah State University (USU) examinations, including background information, governing equations, experimental setup, detailed results, and conclusions for both a steady state and a transient method. Experimental findings of the INL/USU steady state method examinations help to better understand limitations and benefits of two-thermocouple methods, where laboratory results can be extrapolated to in-pile applications. Additionally, results from the transient method offer the immediate potential for in-pile application, as the method reduces the impact on the sample from only a small centerline sensor, measurement times (e.g., only minutes for

  3. 'Shrink' losses in commercially sized corn silage piles: Quantifying total losses and where they occur.

    PubMed

    Robinson, P H; Swanepoel, N; Heguy, J M; Price, T; Meyer, D M

    2016-01-15

    Silage 'shrink' (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term 'shrink' is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90±17, 68±18 and 28±21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses ('older' silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face. PMID:26524271

  4. Complexity analysis of the cost effectiveness of PI-led NASA science missions

    NASA Astrophysics Data System (ADS)

    Yoshida, J.; Cowdin, M.; Mize, T.; Kellogg, R.; Bearden, D.

    For the last 20 years, NASA has allowed Principal Investigators (PIs) to manage the development of many unmanned space projects. Advocates of PI-led projects believe that a PI-led implementation can result in a project being developed at lower cost and shorter schedule than other implementation modes. This paper seeks to test this hypothesis by comparing the actual costs of NASA and other comparable projects developed under different implementation modes. The Aerospace Corporation's Complexity-Based Risk Assessment (CoBRA) analysis tool is used to normalize the projects such that the cost can be compared for equivalent project complexities. The data is examined both by complexity and by launch year. Cost growth will also be examined for any correlation with implementation mode. Defined in many NASA Announcements of Opportunity (AOs), a PI-led project is characterized by a central, single person with full responsibility for assembling a team and for the project's scientific integrity and the implementation and integrity of all other aspects of the mission, while operating under a cost cap. PIs have larger degrees of freedom to achieve the stated goals within NASA guidelines and oversight. This study leverages the definitions and results of previous National Research Council studies of PI-led projects. Aerospace has defined a complexity index, derived from mission performance, mass, power, and technology choices, to arrive at a broad representation of missions for purposes of comparison. Over a decade of research has established a correlation between mission complexity and spacecraft development cost and schedule. This complexity analysis, CoBRA, is applied to compare a PI-led set of New Frontiers, Discovery, Explorers, and Earth System Science Pathfinder missions to the overall NASA mission dataset. This reveals the complexity trends against development costs, cost growth, and development era.

  5. Piling underwater noise impact on migrating salmon fish during Lithuanian LNG terminal construction (Curonian Lagoon, Eastern Baltic Sea Coast).

    PubMed

    Bagočius, Donatas

    2015-03-15

    Development of human activities in the Klaipėda strait generates a wide spectrum of underwater noise. In the fall of 2013, at the liquid natural gas terminal construction site in the shallow Curonian Lagoon area, an assessment of possible negative impacts on migrating salmon fish caused by pile driving noise was made. It is well known that impact hammer pile driving generates pulses with extremely high underwater noise levels. The obtained results proved that the pile hammering into the lagoon bottom generated pulses with a sound exposure level of 218 dB re 1 μPa(2) s @1m thus posing a risk to the migrating fish.

  6. The ability of subsoils to attenuate metals in coal pile leachate. Final report

    SciTech Connect

    Zelmanowitz, S.; Boyle, W.C.; Armstrong, D.E.; Park, J.K.

    1992-09-01

    Research was performed to investigate potential groundwater contamination due to coal pile leachates. Laboratory-generated and field-collected coal pile leachates were analyzed for dissolved organic carbon (DOC), dissolved ions, pH, and chelation potential of the organic acids. Two soil column studies were performed. Column study 1 involved leaching three soils (sand, a silt loam, and a silt loam with 4% CaCO{sub 3} added) with dilute sulfuric acid solutions at pH 1.5, 3.5, and 5.6. Column leachates were analyzed for pH, dissolved silica, cations, and anions. During the second column study pH 1.5 synthetic coal pile leachate was leached through the three soils. Redox potential, pH, dissolved cations and anions of column leachates were determined. A batch experiment was performed in which Plano silt loam with and without CaCO{sub 3} was equilibrated with synthetic coal pile leachate containing 0, 50 or 100 mg/L fulvic acids (FAs). Equilibrated solutions were analyzed for pH, DOC, Fe, Zn and Cd. Field-collected coal pile leachate was more acidic and generally contained higher metals concentrations than did the laboratory-generated leachates. The DOC of the field leachate was lower than levels likely to leach out of surface soils. Both silt loam soils were able to buffer pH 3.5 acid, but the sand was not. None of the soils were able to buffer pH 1.5 acid for the entire leaching period. The sand exhibited the lowest buffering ability and the silt loam at low flowrate and silt loam with CaCO{sub 3} showed the most buffering. Breakthrough of metals in synthetic coal pile leachate corresponded with soil buffering capacity. Metals were most mobile on the sand and least mobile on the silt loam with CaCO{sub 3}. For all soils, metals in column effluents reached input levels or above during leaching. In the batch study, FAs at 50 and 100 mg/L decreased iron and zinc attenuation on silt loam with CaCO{sub 3}, did not affect metals attenuation on silt loam without CaCO{sub 3}.

  7. The ability of subsoils to attenuate metals in coal pile leachate. [In ground water in soils

    SciTech Connect

    Zelmanowitz, S.; Boyle, W.C.; Armstrong, D.E.; Park, J.K. . Dept. of Civil and Environmental Engineering)

    1992-09-01

    Research was performed to investigate potential groundwater contamination due to coal pile leachates. Laboratory-generated and field-collected coal pile leachates were analyzed for dissolved organic carbon (DOC), dissolved ions, pH, and chelation potential of the organic acids. Two soil column studies were performed. Column study 1 involved leaching three soils (sand, a silt loam, and a silt loam with 4% CaCO{sub 3} added) with dilute sulfuric acid solutions at pH 1.5, 3.5, and 5.6. Column leachates were analyzed for pH, dissolved silica, cations, and anions. During the second column study pH 1.5 synthetic coal pile leachate was leached through the three soils. Redox potential, pH, dissolved cations and anions of column leachates were determined. A batch experiment was performed in which Plano silt loam with and without CaCO{sub 3} was equilibrated with synthetic coal pile leachate containing 0, 50 or 100 mg/L fulvic acids (FAs). Equilibrated solutions were analyzed for pH, DOC, Fe, Zn and Cd. Field-collected coal pile leachate was more acidic and generally contained higher metals concentrations than did the laboratory-generated leachates. The DOC of the field leachate was lower than levels likely to leach out of surface soils. Both silt loam soils were able to buffer pH 3.5 acid, but the sand was not. None of the soils were able to buffer pH 1.5 acid for the entire leaching period. The sand exhibited the lowest buffering ability and the silt loam at low flowrate and silt loam with CaCO{sub 3} showed the most buffering. Breakthrough of metals in synthetic coal pile leachate corresponded with soil buffering capacity. Metals were most mobile on the sand and least mobile on the silt loam with CaCO{sub 3}. For all soils, metals in column effluents reached input levels or above during leaching. In the batch study, FAs at 50 and 100 mg/L decreased iron and zinc attenuation on silt loam with CaCO{sub 3}, did not affect metals attenuation on silt loam without CaCO{sub 3}.

  8. In-pile and post-irradiation creep of type 304 stainless steel under different neutron spectra

    NASA Astrophysics Data System (ADS)

    Kurata, Y.; Itabashi, Y.; Mimura, H.; Kikuchi, T.; Amezawa, H.; Shimakawa, S.; Tsuji, H.; Shindo, M.

    2000-12-01

    In addition to post-irradiation creep tests, in-pile creep tests were performed using newly developed technology with in situ measurement under different neutron spectra. The in-pile creep properties of type 304 stainless steel at 550°C appear to depend on neutron spectrum, but a spectral effect on post-irradiation creep properties is not clearly seen. The rupture time of in-pile creep under a high thermal neutron flux condition is the shortest. The order of the rupture time following the high thermal flux condition is post-irradiation creep, in-pile creep with a thermal neutron shield condition and finally creep of unirradiated material, all in increasing order. It is suggested that the acceleration of creep deformation and fracture observed in irradiation creep tests may be related to enhancement of thermal creep in terms of FMD increased under a high thermal neutron flux in addition to increased helium embrittlement.

  9. A simple model to predict soil resistance to driving for long piles in deepwater normally consolidated clays

    SciTech Connect

    Dutt, R.N.; Doyle, E.H.; Collins, J.T.; Ganguly, P.

    1995-12-01

    As the exploration and development for offshore oil and gas reserves moves into the deepwater environment of the continental slope, a good model is necessary to evaluate drivability of large-diameter, long piles in normally consolidated clays. Procedures are available to predict soil resistance to driving in stiff to hard overconsolidated clays of the North Sea and the Arabian Gulf. Use of these procedures in normally consolidated clays grossly overpredicts soil resistance. Such gross overpredictions result in the mobilization of larger hammers or thicker pile wall than necessary for pile installation. A simple model is proposed to estimate soil resistance to driving. Case histories of recent deepwater pile installations are presented to illustrate the adequacy of the new procedure in deepwater normally consolidated clays.

  10. Time-domain solution for transient dynamic response of a large-diameter thin-walled pipe pile

    NASA Astrophysics Data System (ADS)

    Ding, Xuanming; Liu, Hanlong; Chu, Jian; Cheng, Ke

    2015-06-01

    The propagation of stress waves in a large-diameter pipe pile for low strain dynamic testing cannot be explained properly by traditional 1D wave theories. A new computational model is established to obtain a wave equation that can describe the dynamic response of a large-diameter thin-walled pipe pile to a transient point load during a low strain integrity test. An analytical solution in the time domain is deduced using the separation of variables and variation of constant methods. The validity of this new solution is verified by an existing analytical solution under free boundary conditions. The results of this time domain solution are also compared with the results of a frequency domain solution and field test data. The comparisons indicate that the new solution agrees well with the results of previous solutions. Parametric studies using the new solution with reference to a case study are also carried out. The results show that the mode number affects the accuracy of the dynamic response. A mode number greater than 10 is required to enable the calculated dynamic responses to be independent of the mode number. The dynamic response is also greatly affected by soil properties. The larger the side resistance, the smaller the displacement response and the smaller the reflected velocity wave crest. The displacement increases as the stress waves propagate along the pile when the pile shaft is free. The incident waves of displacement and velocity responses of the pile are not the same among different points in the circumferential direction on the pile top. However, the arrival time and peak value of the pile tip reflected waves are almost the same among different points on the pile top.

  11. Calibration of the climatic signal in a new pollen sequence from La Grande Pile

    SciTech Connect

    Guiot, J.; Reille, M.; Beaulieu, J.L. de; Pons, A.

    1992-01-01

    A new core, GPXX, from La Grande Pile (Vosges, France) has enabled a more precise evaluation of pollen data concerning the last climatic cycle at this site and has enabled reconstruction of the monthly temperature and precipitation. This paper shows that the various components of the reconstructed climatic signal are clearly separated and that they are coherent with the vegetation dynamics. The Eemian interglacial was influenced first by an oceanic climate and second by a more continental one. The two interstadials, St-Germain I and II, were mainly continental. These three temperate periods ended with a cool and humid transition period dominated by boreal forests, which may have been favorable to ice accretion. The Dansgaard-Oeschger oscillations from 55 to 25 Kyr BP are not significantly recorded in La Grande Pile. 13 refs., 2 figs.

  12. Modelling nitrogen and carbon interactions in composting of animal manure in naturally aerated piles.

    PubMed

    Oudart, D; Robin, P; Paillat, J M; Paul, E

    2015-12-01

    Composting animal manure with natural aeration is a low-cost and low-energy process that can improve nitrogen recycling in millions of farms world-wide. Modelling can decrease the cost of choosing the best options for solid manure management in order to decrease the risk of loss of fertilizer value and ammonia emission. Semi-empirical models are suitable, considering the scarce data available in farm situations. Eleven static piles of pig or poultry manure were monitored to identify the main processes governing nitrogen transformations and losses. A new model was implemented to represent these processes in a pile considered as homogeneous. The model is based on four modules: biodegradation, nitrogen transformations and volatilization, thermal exchanges, and free air space evolution. When necessary, the parameters were calibrated with the data set. The results showed that microbial growth could reduce ammonia volatilization. Greatest nitrogen conservation is achieved when microbial growth was limited by nitrogen availability.

  13. Sorting it Out: Pile Sorting as a Mixed Methodology for Exploring Barriers to Cancer Screening

    PubMed Central

    Gajewski, Byron J.; Perdue, David G.; Cully, Angel; Cully, Lance; Greiner, K. Allen; Choi, Won S.; Daley, Christine Makosy

    2013-01-01

    We discuss a mixed methodology for analyzing pile sorting data. We created a list of 14 barriers to colon cancer screening and recruited 18, 13, and 14 participants from three American Indian (AI) communities to perform pile sorting. Quantitative data were analyzed by cluster analysis and multidimensional scaling. Differences across sites were compared using permutation bootstrapping. Qualitative data collected during sorting were compiled by AI staff members who determined names for the clusters found in quantitative analysis. Results showed 5 clusters of barriers in each site although barriers in the clusters varied slightly across sites. Simulation demonstrated type I error rates around the nominal 0.05 level whereas power depended on the numbers of clusters, and between and within cluster variability. PMID:25143659

  14. Report On Design And Preliminary Data Of Halden In-Pile Creep Rig

    SciTech Connect

    Terrani, Kurt A; Karlsen, T. M.; Yamamoto, Yukinori

    2015-09-01

    A set of in-pile creep tests is ongoing in the Halden reactor on ORNL’s candidate accident tolerant fuel cladding materials. These tests are meant to provide essential material property information that is needed for an informed analysis of these fuel concepts under normal operating conditions. These tests provide detailed information regarding swelling, thermal creep, and irradiation creep rates of these materials. The results to date have been compared with the limited set of information available in literature that is form irradiation tests in other reactors or out-of-pile tests. Most of the results are in good agreement with prior literature, except for irradiation creep rate of SiC. To elucidate the difference between the HFIR and Halden test results continued testing is necessary. The tests describe in this progress report are ongoing and will continue for at least another year.

  15. Spontaneous formation of dual stratification patterns in a large quasi-two-dimensional sand pile

    NASA Astrophysics Data System (ADS)

    Shimokawa, Michiko; Ohta, Shonosuke

    2008-01-01

    By pouring a mixture of two types of grains into a large vertical cell with a narrow space, we discovered a dual stratification pattern consisting of two different wavelengths at the upper and lower regions of the resulting sand pile. In the formation of this pattern, we also observed an additional type of kink—a wave that moves toward the top of the sand pile along the slope. The kink, herein called a trapped kink, is essential for the formation of dual stratification patterns. Asymmetric probability distributions are obtained from measurement of the position where the kinks are generated. We proposed a phenomenological model to describe the kink generation process. The results analyzed by this model agree with experimental distributions.

  16. Event by event pile-up compensation in digital timestamped calorimetry

    NASA Astrophysics Data System (ADS)

    Vencelj, M.; Bučar, K.; Novak, R.; Wörtche, H. J.

    2009-08-01

    In digital nuclear calorimetry, the effect on measured pulse amplitudes by piling up of pulses can be compensated based on the pulses' respective timestamps, making use of the fact that, for stable pulse shapes, the amount of pile-up induced error at each pulse amplitude measurement is completely determined by the amplitudes and precise occurrences in time of the neighboring pulses. We propose here a compensation method, based on the above observation, suitable for real-time as well as off-line implementation. Successful tests performed off-line both on synthetic and experimental data are shown as a proof of principle. We further propose a draft architectural approach to real-time compensation schemes of this functionality and the corresponding interaction with the experimental controls.

  17. Modelling nitrogen and carbon interactions in composting of animal manure in naturally aerated piles.

    PubMed

    Oudart, D; Robin, P; Paillat, J M; Paul, E

    2015-12-01

    Composting animal manure with natural aeration is a low-cost and low-energy process that can improve nitrogen recycling in millions of farms world-wide. Modelling can decrease the cost of choosing the best options for solid manure management in order to decrease the risk of loss of fertilizer value and ammonia emission. Semi-empirical models are suitable, considering the scarce data available in farm situations. Eleven static piles of pig or poultry manure were monitored to identify the main processes governing nitrogen transformations and losses. A new model was implemented to represent these processes in a pile considered as homogeneous. The model is based on four modules: biodegradation, nitrogen transformations and volatilization, thermal exchanges, and free air space evolution. When necessary, the parameters were calibrated with the data set. The results showed that microbial growth could reduce ammonia volatilization. Greatest nitrogen conservation is achieved when microbial growth was limited by nitrogen availability. PMID:26403389

  18. Arch size distribution in a two-dimensional pile of disks

    NASA Astrophysics Data System (ADS)

    Aguirre, M. A.; Pugnaloni, L. A.; Divoux, T.; Grande, J. G.

    2009-06-01

    Arch formation in a granular pile is a dynamical process. Staring at a static pile one cannot identify such structures. Indeed, it is necessary to know which grains are in contact, but also to access the whole history of the packing formation to distinguish the contacts which really sustain arches. In a recent article, arch formation has been studied numerically [Arévalo et al., Phys. Rev. E 74, 021303 (2006)]. Here, we report preliminary results of an experiment which consists of a time-resolved study of arch formation during the deposition of a disk assembly. The whole experiment is horizontally set. A conveyor belt makes it possible to tune the disk deposition-rate and thus to follow entirely the deposition dynamics. We compare our experimental findings to the previously cited numerical study.

  19. Sealable joint steel sheet piling for groundwater control and remediation: Case histories

    SciTech Connect

    Smyth, D.; Jowett, R.; Gamble, M.

    1997-12-31

    The Waterloo Barrier{trademark} steel sheet piling (patents pending) incorporates a cavity at each interlocking joint that is flushed clean and injected with sealant after the piles have been driven into the ground to form a vertical cutoff wall. The installation and sealing procedures allow for a high degree of quality assurance and control. Bulk wall hydraulic conductivities of 10{sup -8} to 10{sup -10} cm/sec have been demonstrated at field installations. Recent case histories are presented in which Waterloo Barrier{trademark} cutoff walls are used to prevent off-site migration of contaminated groundwater or soil gases to adjacent property and waterways. Full enclosures to isolate DNAPL source zones or portions of contaminated aquifers for pilot-scale remediation testing will also be described. Monitoring data will be used to demonstrate the effectiveness of the Waterloo Barrier{trademark} in these applications.

  20. The strength of rubble-pile bodies: Theory, observations, and predictions

    NASA Astrophysics Data System (ADS)

    Scheeres, D.; Sanchez, P.

    2014-07-01

    The strength and morphology of a rubble-pile body will control how fast it can rotate before shedding mass or deforming, influence the process by which multi-component asteroid systems are created, and could have significance for the mitigation of hazardous near-Earth asteroids (NEA) should this be necessary in the future [1,2,3]. The morphology of these bodies, including the size distribution of boulders and grains internal to the system, the macro-porosity of these bodies, and the shapes and spin states of these bodies, are important for understanding and interpreting spacecraft imaging of asteroids, for predicting the end-state evolution of these bodies, and for gaining insight into their formation circumstances. Despite these compelling issues and questions, real insight on the strength of rubble-pile bodies and their morphology remains elusive. We explore a theory recently developed by us [3] for the morphology and strength of a rubble-pile body based on the properties of cohesive powders and show that several observations of small asteroid properties are consistent with the predictions of this model. That small asteroids can be rubble-pile bodies is clear based on several lines of evidence, including spacecraft imaging and sample analysis of Itokawa [4,5], the existence of the rotation spin rate barrier for bodies larger than a few hundred meters [6], and the recent observations of disrupting asteroids in the main belt [7,8]. A simple extrapolation from these observations are that bodies of at least a few hundred meters and larger are composed of a size distribution of components that range from decameter-sized boulders down to micron-sized grains. The relevant questions then become what the characteristics of these size distributions are and what physical implications for the strength of these bodies arise from this morphology. Based on the theory of cohesive granular mechanics [9] combined with a thorough review of results from the Hayabusa mission [4

  1. Effect of Pile-Driving Sounds on the Survival of Larval Fish.

    PubMed

    Bolle, Loes J; de Jong, Christ A F; Bierman, Stijn M; van Beek, Pieter J G; Wessels, Peter W; Blom, Ewout; van Damme, Cindy J G; Winter, Hendrik V; Dekeling, René P A

    2016-01-01

    Concern exists about the potential effects of pile-driving sounds on fish, but evidence is limited, especially for fish larvae. A device was developed to expose larvae to accurately reproduced pile-driving sounds. Controlled exposure experiments were carried out to examine the lethal effects in common sole larvae. No significant effects were observed at zero-to-peak pressure levels up to 210 dB re 1 μPa(2) and cumulative sound exposure levels up to 206 dB re 1 μPa(2)·s, which is well above the US interim criteria for nonauditory tissue damage in fish. Experiments are presently being carried out for European sea bass and herring larvae. PMID:26610948

  2. Scratch hardness evaluation with in-situ pile-up effect estimation

    NASA Astrophysics Data System (ADS)

    Useinov, A. S.; Useinov, S. S.

    2012-09-01

    The scratch test is a very powerful technique for measuring hardness at very shallow penetration depths. In the present work, the scratching protocol and data analysis were extended by combining the initial surface profile, the instrument compliance, thermal drift and indenter displacement during the test, which allows reconstruction of the complete indenter trajectory during the scratch test. The analysis of such a diagram leads to the in situ estimation of pile-up sizes and their influence on the area of contact between the indenter and the material. As a result, criteria for a scratch width estimation algorithm can be formalized as well as scratching contact depth can be derived. Based on the indenter apex shape characterized with scanning probe microscopy, it has been shown that lateral elastic recovery takes place during the scratch test. The proposed analysis was applied to the measurement of scratch hardness for several materials known for different piling and elastic recovery behavior during mechanical testing.

  3. Cathodic protection system design for steel pilings of a wharf structure

    SciTech Connect

    Nikolakakos, S.

    1999-07-01

    Corrosion of steel pilings in sea and brackish water is mostly due to the establishment of localized corrosion cells and the effects of the tidal changes. The most frequently used corrosion protection systems are coatings and/or cathodic protection. These protective systems when properly designed, installed and operated are very effective in preventing corrosion problems. The design of a cathodic protection system, in order to be effective and reliable, must take into consideration all technical design criteria, the type of materials used, the geometric shape of the structure, environmental conditions, site restrictions, and any outside interferences. These design considerations, as well as the use of design data and an overall design methodology for a cathodic protection system for pipe and sheet piling used in a wharf structure, are discussed in this paper.

  4. Carbon-14 dates at grande pile: correlation of land and sea chronologies.

    PubMed

    Woillard, G M; Mook, W G

    1982-01-01

    Sixteen radiocarbon dates extending back to 70,000 years provide a chronology for the continuous continental pollen record of Grande Pile. This record reflects climatic changes over the last 140,000 years in northeastern France. The cold period initiating the Middle Weichselian, dated previously at 55,000 years, is dated at 70,000 years before the present (B.P.) at Grande Pile. This event is marked by the disappearance of deciduous forests at this site. The Early Weichselian is placed before 70,000 years B.P. A correlation with the oxygen isotope stages from oceanic records is demonstrated until 70,000 years B.P. and attempted beyond.

  5. The characterization of Vicker`s microhardness indentations and pile-up profiles as a strain-hardening microprobe

    SciTech Connect

    Santos, C. Jr.; Odette, G.R.; Lucas, G.E.; Schroeter, B.; Klinginsmith, D.; Yamamoto, T.

    1998-04-01

    Microhardness measurements have long been used to examine strength properties and changes in strength properties in metals, for example, as induced by irradiation. Microhardness affords a relatively simple test that can be applied to very small volumes of material. Microhardness is nominally related to the flow stress of the material at a fixed level of plastic strain. Further, the geometry of the pile-up of material around the indentation is related to the strain-hardening behavior of a material; steeper pile-ups correspond to smaller strain-hardening rates. In this study the relationship between pile-up profiles and strain hardening is examined using both experimental and analytical methods. Vickers microhardness tests have been performed on a variety of metal alloys including low alloy, high Cr and austenitic stainless steels. The pile-up topology around the indentations has been quantified using confocal microscopy techniques. In addition, the indentation and pile-up geometry has been simulated using finite element method techniques. These results have been used to develop an improved quantification of the relationship between the pile-up geometry and the strain-hardening constitutive behavior of the test material.

  6. A semi-analytical model for the prediction of underwater noise from offshore pile driving

    NASA Astrophysics Data System (ADS)

    Tsouvalas, A.; Metrikine, A. V.

    2013-06-01

    Underwater noise from offshore pile driving gained considerable attention in recent years mainly due to the large scale construction of offshore wind farms. The most common foundation type of a wind turbine is a monopile, upon which the wind tower rests. The pile is driven into place with the help of hydraulic hammers. During the hammering of the pile, high levels of noise are generated which are known to produce deleterious effects on both mammals and fish. In this work, a linear semi-analytical model is developed for predicting the levels of underwater noise for a wide range of system parameters. The model incorporates all major parts of the system. The hydraulic hammer is substituted by an external force, the pile is described as a thin circular cylindrical shell, the water is modelled as a compressible fluid and the water-saturated seabed is defined by distributed springs and dashpots in all directions. The solution of the coupled vibroacoustic problem is based on the representation of the response of the complete system on the modal basis of the in vacuo shell structure. The influence that the inter-modal coupling, the choice of the soil parameters and the acoustic impedance of the seabed have on the generated noise levels is studied in the frequency domain. Strong and weak points of the present model are discussed on the basis of a comparison with a set of available experimental data. The obtained results show the capability of the model to predict the underwater noise levels both qualitatively and quantitatively.

  7. Evolving morphology of thermochemical piles caused by accumulation of subducted oceanic crust

    NASA Astrophysics Data System (ADS)

    Li, M.; McNamara, A. K.

    2015-12-01

    Seismic tomography results have shown two large low shear velocity provinces (LLSVPs) in the lowermost mantle beneath Africa and Pacific. The LLSVPs have been hypothesized to be caused by large-scale compositional heterogeneity. Two hypotheses have been proposed for the origin of this compositional heterogeneity: (1) primordial material formed during Earth's early differentiation, and (2) accumulations of subducted oceanic crust on the core-mantle boundary (CMB). Previous geodynamical calculations often show that stable thermochemical piles caused by primordial material have sharp boundaries. So, if the accumulation of subducted oceanic crust has different morphology than that of piles caused by primordial material, we may be able to constrain the origin of compositional heterogeneity from high resolution seismic observations of the boundaries of LLSVPs.Here, we performed geodynamic calculations to investigate the morphology of accumulation of subducted oceanic crust on the CMB. We found that the ability of subducted oceanic crust to accumulate on the CMB and the sharpness of the boundaries of the accumulations both strongly depends on the crustal thickness. A thick (e.g., ~30 km) oceanic crust produced from the early hot mantle can form into large-scale accumulations on the CMB, but with fuzzy and diffuse top boundaries. However, as the oceanic crust becomes thinner, it becomes more difficult to accumulate on the CMB, and the top boundaries of the accumulations of subducted oceanic crust also gradually become sharp, more like that of piles caused by primordial material. Thus, a sharp top boundaries of LLSVPs in the present-day Earth does not guarantee that they are caused by piles of primordial material. In addition, as the oceanic crust becomes thinner, more subducted oceanic crust is entrained and recycled to shallow depth, which may have important implications for geochemical observations on Earth's surface.

  8. D-Area Coal Pile Runoff Basin Sulfate Reduction Literature Review and Feasibility Report

    SciTech Connect

    Phifer, M.A.

    2002-02-08

    The D-Area Coal Pile Runoff Basin groundwater plume is acidic and contains heavy metals and sulfate. Portions of this plume near the source have a pH approaching 2.0 and heavy metal concentrations exceeding Maximum Primary Drinking Water Regulations. Remedial action for the groundwater contaminated by this RCRA/CERCLA unit will be required to mitigate the migration of highly contaminated groundwater towards adjacent surface water bodies.

  9. Design and performance evaluation of a cryogenic condenser for an in-pile experiment

    NASA Technical Reports Server (NTRS)

    Graham, R. W.; Crum, R. J.; Hsu, Y.

    1972-01-01

    An apparatus was designed to enable in-pile irradiation of materials in liquid hydrogen at cryogenic temperatures. One of the principal components of this apparatus was a horizontal tube condenser. The performance of the condenser was evaluated by running a liquid-nitrogen prototype of the apparatus at heat loads comparable to or greater than those expected during the irradiation. The test showed that the condenser was capable of handling the design heat load and that the design procedure was sound.

  10. Free-radical concentrations and other properties of pile-irradiated coals

    USGS Publications Warehouse

    Friedel, R.A.; Breger, I.A.

    1959-01-01

    Five coals reacted quite differently when they were exposed to pile-irradiation. Little or no change was found in free-radical content for the three coals of lowest carbon content, whereas the two coals of highest carbon content were found to have a considerable increase in free-radical content. The infrared spectra and the apparent hardness of the irradiated coals of higher carbon content indicate that polymerization occurred. Radiation of these coals in chemical reagents may promote reactivity.

  11. Common Sole Larvae Survive High Levels of Pile-Driving Sound in Controlled Exposure Experiments

    PubMed Central

    Bolle, Loes J.; de Jong, Christ A. F.; Bierman, Stijn M.; van Beek, Pieter J. G.; van Keeken, Olvin A.; Wessels, Peter W.; van Damme, Cindy J. G.; Winter, Hendrik V.; de Haan, Dick; Dekeling, René P. A.

    2012-01-01

    In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa2 (zero to peak pressures up to 32 kPa) and single pulse sound exposure levels up to 186 dB re 1µPa2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea) larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised. PMID:22431996

  12. Influence of wear, pile height, and cleaning method on removal of mite allergen from carpet.

    PubMed

    Causer, Simon M; Lewis, Roger D; Batek, Joseph M; Ong, Kee-Hean

    2004-04-01

    Carpet is a major sink for house dust mite allergen. Vacuum extraction methods have been shown to reduce concentrations of such allergen in dust, but the influence of carpet construction and cleaning parameters on the efficiency of extraction is poorly understood. The objective of this study was to determine the effect of construction, degree of wear, and cleaning method on ease of removal of the primary allergen (Der f I) derived from the North American house-dust mite, Dermatophagoides Farinae. Carpets of different pile heights were seeded with house dust, some were then subjected to artificial wear, and all were then either dry vacuumed or wet extracted. The Der f I content of carpet cores was measured at each stage. As a result, the degree of wear and pile height were shown to be the two most important factors determining ease of Der f I removal from carpet. For worn carpet, dry vacuuming of short pile constructions was shown to be significantly more effective (p pile height constructions, while removal of Der f I using either wet or dry vacuum extraction techniques was shown to be more efficient (>61%) for unworn carpet than for worn carpet (<30%). Only minor differences between types of cleaning method (wet vs. dry) were found. This study suggests that carpets differ greatly in their propensity to retain allergens, and that a consideration of carpet age, construction, and cleaning regime is important when advising the merits of different floor covering types, and on allergen avoidance techniques.

  13. Tailings Pile Seepage Model The Atlas Corporation Moab Mill Moab, Utah

    SciTech Connect

    Easterly, CE

    2001-11-05

    The project described in this report was conducted by personnel from Oak Ridge National Laboratory's Grand Junction Office (ORNL/GJ). This report has been prepared as a companion report to the Limited Groundwater Investigation of the Atlas Corporation Moab Mill, Moab, Utah. The purpose of this report is to present the results of the tailings pile seepage modeling effort tasked by the U.S. Nuclear Regulatory Commission (NRC).

  14. Stopping of avalanches : long-termed relaxation of a granular pile

    NASA Astrophysics Data System (ADS)

    Deboeuf, S.; Dauchot, O.; Lajeunesse, E.; Vilotte, J. P.

    2003-04-01

    Natural slopes destabilization and gravitational flows endanger local buildings and populations. Prevention of these natural risks requires a better understanding of elementary mecanisms, which can be studied in a model granular medium. Our experiment examines the quasi-static relaxation of a pile of iron beads following the occurence of an avalanche. The pile is set up in a rotating drum. Avalanches are created by rotating the drum. After a given avalanche, the drum is stopped and the pile slope is driven to θ_i<θrepos. The pile relaxation is then recorded by a video camera and micro-displacements of the beads are detected, through image processing. The relaxation can last very long time (1000s) compared to the microscopic time scale of one bead (0.01s). Among several realisations, this long-termed dynamics is all the more probable as θ_i is large. The temporal analysis reveals 2 simultaneous dynamics : -1) A fast irreversible dynamics (caracterised by a decreasing time 1/γ), induced by the fast individual micro-moves, whose origin is simply gravity (existing for all realisations). -2) Intermittent boosts (occuring at a mean frequency λ), in the way of slower collective motions (more probable for realisations at large θ_i), which re-initiate micro-moves. The competition of these 2 dynamics, whith opposite effects, when on the same time scale, creates the observed long relaxation time. Experimentally, for small θ_i, λ<<γ, that is irreversible dynamics dominates the relaxation; whereas for large θ_i, λ=γ, that is decreasing dynamics and reinjections process compete and extend the total relaxation duration. Physically, gravitational packing leads to the equilibrium of the granular medium, but according to local configurations, can result in internal destabilizations by breaking contacts. These hypothesis shall now be further examined by using numerical simulations (Contact Dynamics).

  15. Scaling the hydrological and geochemical processes that control drainage from waste-rock piles: an overview.

    NASA Astrophysics Data System (ADS)

    Pedretti, Daniele; Peterson, Holly; Blackmore, Sharon; Javadi, Mehrnoush; Lorca Ugalde, Maria E.; Laurenzi, Laura; St Arnault, Melanie; Skierszkan, Elliot; Mayer, K. Ulrich; Beckie, Roger D.

    2014-05-01

    Waste rock is a material that must be excavated to access ore. It is typically disposed of in large piles proximal to the mine site where exposure to oxygen and water promotes oxidation of sulfides, releasing metals, heat and acid. The quality of drainage from waste rock is strongly affected by physical processes that control fluid (water and gas) movement. These processes are complex, due largely to the heterogeneity in grain size, pile structure and mineral distribution. Present assessment methods tend to focus on relatively rapid, small-scale tests which have limited predictive ability at field scales. Acid-base accounting and various leaching procedures such as humidity cells can provide useful information, but fail to represent the larger-scale physical and geochemical processes. Indeed, studies at several sites have shown that the rate of waste rock chemical weathering can be many times faster in smaller-scale experiments than is inferred from observations of outflow in larger-scale piles. This so-called scale effect is often attributed to hydrologic processes, rather than differences between lab and field settings in composition or the chemical environment. Fluid flow in waste rock probably represents the largest source of uncertainty in current predictive efforts to characterize the evolution of solute loadings through time. Modeling could perhaps one day routinely be used to link small-scale assessments to more easily measurable physical attributes such as grain size, general pile structure and grain-size segregation and provide reliable predictions of field-scale behavior without the need for large-scale experiments. This contribution provides an overview of the processes controlling drainage quantity and quality and the relationship between smaller-scale, short-time observations and long-term field-scale dynamics.

  16. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    structure des oscillations de conductance en fonction du flux du champ magnétique de période h/e dont l'amplitude est beaucoup plus importante que celle mesurée sur un réseau carré de même dimension. Cette différence constitue une signature d'un effet de localisation induit par le champ magnétique sur la topologie mathcal{T}3. Pour des valeurs spécifiques du champ magnétique, du fait des interférences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limitée à un ensemble fini de cellule du réseau appelé cage. De la dépendance en température des oscillations de période h/e mesurées sur le réseau mathcal{T}3 nous avons tiré une longueur caractéristique qui peut être rattachée au périmètre des cages. Un phénomène inattendu fut l'observation, pour des champs magnétiques plus importants, d'un doublement de fréquence des oscillations. Ces oscillations de période h/2e pouvant avoir une amplitude supérieure aux oscillations de période h/e, une interprétation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur électrique des fils constituant le réseau et donc celle du nombre de canaux par brin a été étudiée en réalisant des grilles électrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont été mesurés.

  17. Impact de la preparation des anodes crues et des conditions de cuisson sur la fissuration dans des anodes denses

    NASA Astrophysics Data System (ADS)

    Amrani, Salah

    La fabrication de l'aluminium est realisee dans une cellule d'electrolyse, et cette operation utilise des anodes en carbone. L'evaluation de la qualite de ces anodes reste indispensable avant leur utilisation. La presence des fissures dans les anodes provoque une perturbation du procede l'electrolyse et une diminution de sa performance. Ce projet a ete entrepris pour determiner l'impact des differents parametres de procedes de fabrication des anodes sur la fissuration des anodes denses. Ces parametres incluent ceux de la fabrication des anodes crues, des proprietes des matieres premieres et de la cuisson. Une recherche bibliographique a ete effectuee sur tous les aspects de la fissuration des anodes en carbone pour compiler les travaux anterieurs. Une methodologie detaillee a ete mise au point pour faciliter le deroulement des travaux et atteindre les objectifs vises. La majorite de ce document est reservee pour la discussion des resultats obtenus au laboratoire de l'UQAC et au niveau industriel. Concernant les etudes realisees a l'UQAC, une partie des travaux experimentaux est reservee a la recherche des differents mecanismes de fissuration dans les anodes denses utilisees dans l'industrie d'aluminium. L'approche etait d'abord basee sur la caracterisation qualitative du mecanisme de la fissuration en surface et en profondeur. Puis, une caracterisation quantitative a ete realisee pour la determination de la distribution de la largeur de la fissure sur toute sa longueur, ainsi que le pourcentage de sa surface par rapport a la surface totale de l'echantillon. Cette etude a ete realisee par le biais de la technique d'analyse d'image utilisee pour caracteriser la fissuration d'un echantillon d'anode cuite. L'analyse surfacique et en profondeur de cet echantillon a permis de voir clairement la formation des fissures sur une grande partie de la surface analysee. L'autre partie des travaux est basee sur la caracterisation des defauts dans des echantillons d'anodes crues

  18. Study of soil interaction in a model building frame with plinth beam supported by pile group

    NASA Astrophysics Data System (ADS)

    Reddy, Ravikumar C.; Rao, Gunneswara T. D.

    2012-12-01

    This paper presents the results of static vertical load tests carried out on a model building frame with plinth beam supported by pile groups embedded in cohesionless soil (sand). The effect of soil interaction on displacements and rotation at the column base and also the shears and bending moments in the building frame were investigated. The experimental results have been compared with those obtained from the finite element analysis and conventional method of analysis. Soil nonlinearity in the axial direction is characterized by nonlinear vertical springs along the length of the pile (τ-z curves) and at the tip of the pile (Q-z curves) and in the lateral direction by the p-y curves. The results reveal that the conventional method gives the shear force in the column by about 20%, the bending moment at the column top about 10%, and at the column base about 20% to 30%, more than those from the experimental results. The response of the frame from the experimental results is in good agreement with that obtained by the nonlinear finite element analysis.

  19. Evaluation of Dynamic Behavior of Pile Foundations for Interim Storage Facilities Through Geotechnical Centrifuge Tests

    SciTech Connect

    Shizuo Tsurumaki; Hiroyuki Watanabe; Akira Tateishi; Kenichi Horikoshi; Shunichi Suzuki

    2002-07-01

    In Japan, there is a possibility that interim storage facilities for recycled nuclear fuel resources may be constructed on quaternary layers, rather than on hard rock. In such a case, the storage facilities need to be supported by pile foundations or spread foundations to meet the required safety level. The authors have conducted a series of experimental studies on the dynamic behavior of storage facilities supported by pile foundations. A centrifuge modeling technique was used to satisfy the required similitude between the reduced size model and the prototype. The centrifuge allows a high confining stress level equivalent to prototype deep soils to be generated (which is considered necessary for examining complex pile-soil interactions) as the soil strength and the deformation are highly dependent on the confining stress. The soil conditions were set at as experimental variables, and the results are compared. Since 2000, the Nuclear Power Engineering Corporation (NUPEC) has been conducting these research tests under the auspices on the Ministry of Economy, Trade and Industry of Japan. (authors)

  20. Numerical simulation on the seismic absorption effect of the cushion in rigid-pile composite foundation

    NASA Astrophysics Data System (ADS)

    Han, Xiaolei; Li, Yaokun; Ji, Jing; Ying, Junhao; Li, Weichen; Dai, Baicheng

    2016-06-01

    In order to quantitatively study the seismic absorption effect of the cushion on a superstructure, a numerical simulation and parametric study are carried out on the overall FEA model of a rigid-pile composite foundation in ABAQUS. A simulation of a shaking table test on a rigid mass block is first completed with ABAQUS and EERA, and the effectiveness of the Drucker-Prager constitutive model and the finite-infinite element coupling method is proved. Dynamic time-history analysis of the overall model under frequent and rare earthquakes is carried out using seismic waves from the El Centro, Kobe, and Bonds earthquakes. The different responses of rigid-pile composite foundations and pile-raft foundations are discussed. Furthermore, the influence of thickness and modulus of cushion, and ground acceleration on the seismic absorption effect of the cushion are analyzed. The results show that: 1) the seismic absorption effect of a cushion is good under rare earthquakes, with an absorption ratio of about 0.85; and 2) the seismic absorption effect is strongly affected by cushion thickness and ground acceleration.

  1. Pile driving zone of responsiveness extends beyond 20 km for harbor porpoises (Phocoena phocoena (L.)).

    PubMed

    Tougaard, Jakob; Carstensen, Jacob; Teilmann, Jonas; Skov, Henrik; Rasmussen, Per

    2009-07-01

    Behavioral reactions of harbor porpoises (Phocoena phocoena) to underwater noise from pile driving were studied. Steel monopile foundations (4 m diameter) for offshore wind turbines were driven into hard sand in shallow water at Horns Reef, the North Sea. The impulsive sounds generated had high sound pressures [source level 235 dB re 1 microPa(pp) at 1 m, transmission loss 18 log(distance)] with a strong low frequency emphasis but with significant energy up to 100 kHz. Reactions of porpoises were studied by passive acoustic loggers (T-PODs). Intervals between echolocation events (encounters) were analyzed, and a significant increase was found from average 5.9 h between encounters in the construction period as a whole to on average 7.5 h between first and second encounters after pile driving. The size of the zone of responsiveness could not be inferred as no grading in response was observed with distance from the pile driving site but must have exceeded 21 km (distance to most distant T-POD station). PMID:19603857

  2. Helical piles: an innovative foundation design option for offshore wind turbines.

    PubMed

    Byrne, B W; Houlsby, G T

    2015-02-28

    Offshore wind turbines play a key part in the renewable energy strategy in the UK and Europe as well as in other parts of the world (for example, China). The majority of current developments, certainly in UK waters, have taken place in relatively shallow water and close to shore. This limits the scale of the engineering to relatively simple structures, such as those using monopile foundations, and these have been the most common design to date, in UK waters. However, as larger turbines are designed, or they are placed in deeper water, it will be necessary to use multi-footing structures such as tripods or jackets. For these designs, the tension on the upwind footing becomes the critical design condition. Driven pile foundations could be used, as could suction-installed foundations. However, in this paper, we present another concept-the use of helical pile foundations. These foundations are routinely applied onshore where large tension capacities are required. However, for use offshore, a significant upscaling of the technology will be needed, particularly of the equipment required for installation of the piles. A clear understanding of the relevant geotechnical engineering will be needed if this upscaling is to be successful. PMID:25583860

  3. Pulse pile-up recovery for the front-end electronics of the PANDA Electromagnetic Calorimeter

    NASA Astrophysics Data System (ADS)

    Tambave, G.; Kavatsyuk, M.; Guliyev, E.; Schreuder, F.; Moeini, H.; Löhner, H.

    2012-11-01

    At the future Facility for Antiproton and Ion Research near Darmstadt in Germany the PANDA detector will be employed to study the charmonium spectrum and to search for narrow exotic hadronic states, predicted by Quantum Chromodynamics. In the PANDA experiment, 1.5 to 15 GeV/c anti-protons will annihilate with a hydrogen target at an average rate of 20MHz. Among the sub-detectors of PANDA is the Electromagnetic Calorimeter (EMC) planned for the studies of electromagnetic transitions and neutral meson decays. Due to the high annihilation rates, the EMC will be exposed to single-detector hit rates up to 500kHz, which may lead to pulse overlap. Hence, to recover the energy and time information of the overlapping pulses, a pulse pile-up recovery method is developed. The method is easy to implement in FPGA for online data processing. The Constant Fraction Timing algorithm is applied at the trailing edge to determine the time stamp of pile-up pulses. The energy and the time information of pile-up pulses can be recovered up to time differences of 50ns, equal to the pulse rise-time, in a large dynamic energy range.

  4. Application of HDMR method to reliability assessment of a single pile subjected to lateral load

    NASA Astrophysics Data System (ADS)

    Bauer, Jerzy; Kozubal, Janusz; Puła, Wojciech; Wyjadłowski, Marek

    2012-10-01

    The paper presents an application of High Dimensional Model Representation (HDMR) to reliability assessment of a single pile subjected to lateral load. The purpose is to compare HDMR with some classical method based on response surface technique. First 3D numerical model of the problem for finite elements computations in the ABAQUS STANDARD program has been presented. The soil model is assumed to be linear elastic. However, contacts between the sidewall and the foundation of the pile and the soil are modelled as Coulomb one with friction and cohesion. Next the Response Surface Method is briefly reviewed in conjunction with reliability approach. Then the High Dimensional Model Representation approach is presented. In our approach the HDMR algorithm is based on polynomial of the second degree. Finally the numerical studies have been carried out. The first series of computations demonstrate the efficiency of HDMR in comparison to neural network approach. The second series allows comparison of reliability indices resulting from three different approaches, namely neural network response surface, first-order HDMR and second-order HDMR. It has been observed that for increasing values of the length of the pile reliability indices reach similar values regardless of the method response surface applied.

  5. Elastoplastic multiphase model for simulating the response of piled raft foundations subject to combined loadings

    NASA Astrophysics Data System (ADS)

    Hassen, G.; de Buhan, P.

    2006-08-01

    A multiphase model and corresponding computational time-saving finite element code is proposed in this paper for predicting the settlements experienced by a piled raft foundation when subject to the combined action of vertical and lateral loadings. This model, which is formulated in the framework of an elastoplastic behaviour for the soil and the reinforcing piles as well, explicitly accounts for the shear and flexural behaviour of the latter. Starting from a simple analytical example where all the concepts attached to this model are clearly illustrated, the main stages leading to its finite element implementation are then presented. The numerical tool thus elaborated, is applied to the simulation of a pile-reinforced strip foundation submitted to a horizontally applied seismic load in addition to a permanent vertical load. One of the key results of such a simulation in terms of design recommendation, lies in the conclusion that, while the shear and flexural contributions of the reinforcement play quite a negligible role in the case of a vertical load (as compared with their axial resistance), they remain absolutely essential for withstanding the seismic lateral loading.

  6. Acoustic stress responses in juvenile sea bass Dicentrarchus labrax induced by offshore pile driving.

    PubMed

    Debusschere, Elisabeth; Hostens, Kris; Adriaens, Dominique; Ampe, Bart; Botteldooren, Dick; De Boeck, Gudrun; De Muynck, Amelie; Sinha, Amit Kumar; Vandendriessche, Sofie; Van Hoorebeke, Luc; Vincx, Magda; Degraer, Steven

    2016-01-01

    Underwater sound generated by pile driving during construction of offshore wind farms is a major concern in many countries. This paper reports on the acoustic stress responses in young European sea bass Dicentrarchus labrax (68 and 115 days old), based on four in situ experiments as close as 45 m from a pile driving activity. As a primary stress response, whole-body cortisol seemed to be too sensitive to 'handling' bias. On the other hand, measured secondary stress responses to pile driving showed significant reductions in oxygen consumption rate and low whole-body lactate concentrations. Furthermore, repeated exposure to impulsive sound significantly affected both primary and secondary stress responses. Under laboratory conditions, no tertiary stress responses (no changes in specific growth rate or Fulton's condition factor) were noted in young sea bass 30 days after the treatment. Still, the demonstrated acute stress responses and potentially repeated exposure to impulsive sound in the field will inevitably lead to less fit fish in the wild. PMID:26561450

  7. Pile driving zone of responsiveness extends beyond 20 km for harbor porpoises (Phocoena phocoena (L.)).

    PubMed

    Tougaard, Jakob; Carstensen, Jacob; Teilmann, Jonas; Skov, Henrik; Rasmussen, Per

    2009-07-01

    Behavioral reactions of harbor porpoises (Phocoena phocoena) to underwater noise from pile driving were studied. Steel monopile foundations (4 m diameter) for offshore wind turbines were driven into hard sand in shallow water at Horns Reef, the North Sea. The impulsive sounds generated had high sound pressures [source level 235 dB re 1 microPa(pp) at 1 m, transmission loss 18 log(distance)] with a strong low frequency emphasis but with significant energy up to 100 kHz. Reactions of porpoises were studied by passive acoustic loggers (T-PODs). Intervals between echolocation events (encounters) were analyzed, and a significant increase was found from average 5.9 h between encounters in the construction period as a whole to on average 7.5 h between first and second encounters after pile driving. The size of the zone of responsiveness could not be inferred as no grading in response was observed with distance from the pile driving site but must have exceeded 21 km (distance to most distant T-POD station).

  8. Helical piles: an innovative foundation design option for offshore wind turbines.

    PubMed

    Byrne, B W; Houlsby, G T

    2015-02-28

    Offshore wind turbines play a key part in the renewable energy strategy in the UK and Europe as well as in other parts of the world (for example, China). The majority of current developments, certainly in UK waters, have taken place in relatively shallow water and close to shore. This limits the scale of the engineering to relatively simple structures, such as those using monopile foundations, and these have been the most common design to date, in UK waters. However, as larger turbines are designed, or they are placed in deeper water, it will be necessary to use multi-footing structures such as tripods or jackets. For these designs, the tension on the upwind footing becomes the critical design condition. Driven pile foundations could be used, as could suction-installed foundations. However, in this paper, we present another concept-the use of helical pile foundations. These foundations are routinely applied onshore where large tension capacities are required. However, for use offshore, a significant upscaling of the technology will be needed, particularly of the equipment required for installation of the piles. A clear understanding of the relevant geotechnical engineering will be needed if this upscaling is to be successful.

  9. PileLine: a toolbox to handle genome position information in next-generation sequencing studies

    PubMed Central

    2011-01-01

    Background Genomic position (GP) files currently used in next-generation sequencing (NGS) studies are always difficult to manipulate due to their huge size and the lack of appropriate tools to properly manage them. The structure of these flat files is based on representing one line per position that has been covered by at least one aligned read, imposing significant restrictions from a computational performance perspective. Results PileLine implements a flexible command-line toolkit providing specific support to the management, filtering, comparison and annotation of GP files produced by NGS experiments. PileLine tools are coded in Java and run on both UNIX (Linux, Mac OS) and Windows platforms. The set of tools comprising PileLine are designed to be memory efficient by performing fast seek on-disk operations over sorted GP files. Conclusions Our novel toolbox has been extensively tested taking into consideration performance issues. It is publicly available at http://sourceforge.net/projects/pilelinetools under the GNU LGPL license. Full documentation including common use cases and guided analysis workflows is available at http://sing.ei.uvigo.es/pileline. PMID:21261974

  10. Numerical Study on plumes and thermochemical piles in plate-mode convection

    NASA Astrophysics Data System (ADS)

    Stein, C.; Brannaschke, K.; Hansen, U.

    2010-12-01

    Plates and plumes are two important aspects of mantle convection that both have large impact on the structure and dynamics of the Earth's mantle. Tectonic plates shield the interior from effective cooling and the movement of plates and subduction processes affect the dynamics of the interior. Thermal plumes and thermochemical piles forming at the core-mantle boundary play a further role in the mixing and evolution of the mantle. We apply a 2D numerical code to investigate the structure and evolution of the mantle in thermal and thermochemical convection. In our model plates form in a self-consistent manner, so that we can study the effect of plate-mode convection. During periods of subduction, we observe the formation of plume clusters. In cases where we apply a strong pressure-dependent viscosity, we find a few, stable Superplumes. In thermochemical convection dense material is viscously trapped by the flow and piled up beneath plumes. We will here discuss the effect of plates on plumes and piles and compare the signals they leave at the surface and core-mantle boundary.

  11. Debris avalanche triggered by sill intrusions in basaltic volcanoes (Piton des Neiges, La Réunion Island)

    NASA Astrophysics Data System (ADS)

    Berthod, C.; Famin, V.; Bascou, J.; Michon, L.; Ildefonse, B.

    2014-12-01

    Debris avalanches derived from the flanks of volcanic islands are among the largest on Earth. Debris avalanches are rare, catastrophic destabilizations that still keep geologists debating about the mechanisms that initiate them and make them travel huge runout distances. To shed light on the trigger of such destabilizations, we studied the inland scar of a debris avalanche deposit cropping out at Piton des Neiges, a dormant and eroded basaltic volcano of La Réunion Island. The avalanche deposit rests on a pile of 50-70 sill intrusions with a shallow northward dip, i.e. toward the sea. We measured the anisotropy of magnetic susceptibility in a transect across the uppermost sill of the pile in contact with the avalanche deposit. This transect reveals a strongly asymmetric magnetic fabric, consistent with a north-directed shear movement of the upper intrusion wall. This suggests that the upper sill induced a co-intrusive shear displacement of the volcano flank toward the sea. The upper sill margin in contact with the avalanche is striated, showing that this intrusion is older than the avalanche. Striae indicate a northward direction of avalanche runout. The upper sill margin also displays a magmatic lineation consistent with a magma flow in the intrusion toward the north. There is thus a striking kinematic consistency between the directions of intrusion propagation and avalanche runout, both oriented toward the sea. From the above results, we propose that repeated sill intrusions, such as observed on Piton des Neiges, increase the instability of a volcanic edifice. Each injection induces an incremental slip of the overlying rock mass, which may eventually end up into a landslide. Sill intrusions associated with seaward displacements of volcano flank, such as inferred for the April 2007 eruption of Piton de la Fournaise (also in La Réunion), should therefore be considered as a potential trigger of debris avalanches.

  12. Alteration and arenization processes of granitic waste rock piles from former uranium Mines in Limousin, France.

    NASA Astrophysics Data System (ADS)

    Kanzari, Aisha; Boekhout, Flora; Gérard, Martine; Galoisy, Laurence; Phrommavanh, Vannapha; Descostes, Michael

    2014-05-01

    France counts approximately 200 former uranium mines, 50 of which are located in the Limousin region. Mining activities between 1945 and 2001 have generated close to 200 000 tons of waste rocks in the Limousin, with uranium levels corresponding essentially to the geological background. Waste rock piles from three former mining sites in this region, were selected according to their age, uranium content and petrological signature. These sites are part of the two-mica granitic complex of St Sylvestre massif, formed 324 million years ago. Granitic blocks that build up the waste rock piles have experienced different processes and intensities of alteration before their emplacement at the surface. These processes are responsible for the petrological heterogeneity throughout the waste rock pile at the time of construction. It is important to make a distinction within waste rocks between natural-cut-off waste rocks and economic-cut-off waste rocks. The latter represents a minority and is linked to stock prices. Natural-cut-off waste rocks contain about 20 ppm of uranium; economic-cut-off waste rocks contain about 100 to 300 ppm of uranium. The aims of this study are to 1) assess the neo-formation of U-bearing minerals hosted by these rocks, and 2) to characterize the weathering processes since the construction of the rock piles, including both mechanical and chemical processes. The structure of the waste rocks piles, from metric blocks to boulders of tens centimeters, induces an enhanced weathering rate, compared to a granitic massif. Mechanical fracturing and chemical leaching by rainwater (arenization) of the waste rocks produce a sandy-silty alteration phase. Silty-clay weathering aureoles of submetric-granitic blocks evolving into technic soil are mainly located below growing birch trees. Sampling on the rock piles was restricted to surface rocks. Samples collected consist mainly of granites, and rare lamprophyres with a high radiometric signal, thereby especially

  13. Total 'shrink' losses, and where they occur, in commercially sized silage piles constructed from immature and mature cereal crops.

    PubMed

    Robinson, P H; Swanepoel, N; Heguy, J M; Price, P; Meyer, D M

    2016-07-15

    Silage 'shrink' (i.e., fresh chop crop lost between ensiling and feedout) represents losses of potential animal nutrients which degrade air quality as volatile carbon compounds. Regulatory efforts have, in some cases, resulted in semi-mandatory mitigations (i.e., dairy farmers select a minimum number of mitigations from a list) to reduce silage shrink, mitigations often based on limited data of questionable relevance to large commercial silage piles where silage shrink may or may not be a problem of a magnitude equal to that assumed. Silage 'shrink' is generally ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost during oven drying (vcoDM). As no research has documented shrink in large cereal silage piles, 6 piles ranging from 1456 to 6297tonnes (as built) were used. Three used cereal cut at an immature stage and three at a mature stage. Physiologically immature silages had generally higher (P<0.01) levels of total volatile fatty acids (especially acetic acid; P=0.01) and total alcohols (P<0.01) than did physiologically mature crops, suggesting higher carbon compound volatilization potential from immature silages. However expressed as WW, oDM and vcoDM, total shrink (as well as from where in the piles it occurred) was little impacted by crop maturity, and whole pile vcoDM shrink was only ~35g/kg. Overall, real shrink losses (vcoDM) of large well managed cereal silage piles were relatively low, and a lower potential contributor to aerosol emissions of volatile carbon compounds than has often been assumed. Losses from the silage mass and the exposed silage face were approximately equal contributors to vcoDM shrink. Mitigations to reduce these relatively low emission levels of volatile organic compounds from cereal silage piles should focus on the ensiled mass and the exposed silage face.

  14. Predicting moisture and economic value of solid forest fuel piles for improving the profitability of bioenergy use

    NASA Astrophysics Data System (ADS)

    Lauren, Ari; Kinnunen, Jyrki-Pekko; Sikanen, Lauri

    2016-04-01

    Bioenergy contributes 26 % of the total energy use in Finland, and 60 % of this is provided by solid forest fuel consisting of small stems and logging residues such as tops, branches, roots and stumps. Typically the logging residues are stored as piles on site before transporting to regional combined heat and power plants for combustion. Profitability of forest fuel use depends on smart control of the feedstock. Fuel moisture, dry matter loss, and the rate of interest during the storing are the key variables affecting the economic value of the fuel. The value increases with drying, but decreases with wetting, dry matter loss and positive rate of interest. We compiled a simple simulation model computing the moisture change, dry matter loss, transportation costs and present value of feedstock piles. The model was used to predict the time of the maximum value of the stock, and to compose feedstock allocation strategies under the question: how should we choose the piles and the combustion time so that total energy yield and the economic value of the energy production is maximized? The question was assessed concerning the demand of the energy plant. The model parameterization was based on field scale studies. The initial moisture, and the rates of daily moisture change and dry matter loss in the feedstock piles depended on the day of the year according to empirical field measurements. Time step of the computation was one day. Effects of pile use timing on the total energy yield and profitability was studied using combinatorial optimization. Results show that the storing increases the pile maximum value if the natural drying onsets soon after the harvesting; otherwise dry matter loss and the capital cost of the storing overcome the benefits gained by drying. Optimized timing of the pile use can improve slightly the profitability, based on the increased total energy yield and because the energy unit based transportation costs decrease when water content in the biomass is

  15. Total 'shrink' losses, and where they occur, in commercially sized silage piles constructed from immature and mature cereal crops.

    PubMed

    Robinson, P H; Swanepoel, N; Heguy, J M; Price, P; Meyer, D M

    2016-07-15

    Silage 'shrink' (i.e., fresh chop crop lost between ensiling and feedout) represents losses of potential animal nutrients which degrade air quality as volatile carbon compounds. Regulatory efforts have, in some cases, resulted in semi-mandatory mitigations (i.e., dairy farmers select a minimum number of mitigations from a list) to reduce silage shrink, mitigations often based on limited data of questionable relevance to large commercial silage piles where silage shrink may or may not be a problem of a magnitude equal to that assumed. Silage 'shrink' is generally ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost during oven drying (vcoDM). As no research has documented shrink in large cereal silage piles, 6 piles ranging from 1456 to 6297tonnes (as built) were used. Three used cereal cut at an immature stage and three at a mature stage. Physiologically immature silages had generally higher (P<0.01) levels of total volatile fatty acids (especially acetic acid; P=0.01) and total alcohols (P<0.01) than did physiologically mature crops, suggesting higher carbon compound volatilization potential from immature silages. However expressed as WW, oDM and vcoDM, total shrink (as well as from where in the piles it occurred) was little impacted by crop maturity, and whole pile vcoDM shrink was only ~35g/kg. Overall, real shrink losses (vcoDM) of large well managed cereal silage piles were relatively low, and a lower potential contributor to aerosol emissions of volatile carbon compounds than has often been assumed. Losses from the silage mass and the exposed silage face were approximately equal contributors to vcoDM shrink. Mitigations to reduce these relatively low emission levels of volatile organic compounds from cereal silage piles should focus on the ensiled mass and the exposed silage face. PMID:27054492

  16. Etude des effets du martelage repetitif sur les contraintes residuelles

    NASA Astrophysics Data System (ADS)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  17. Comparison of Different Methods for Determination of Pyrite Oxidation Rate in Wate Rock Pile at Mine Doyon, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Sracek, O.; Nicholson, R.; Gélinas, P.; Lefebvre, R.

    2004-05-01

    Mine Doyon is a gold mine located close to Noranda, Québec, Canada. The South waste rock pile contains mostly highly friable sericite schists with pyrite content up to 7 wt percent. Oxidation of pyrite resulted in the production of acid mine drainage with pH values of about 2.0, and sulfate concentrations in pore water above 200 g/L. The waste rock material is characterized by high permeability allowing thermally driven convective supply of oxygen at temperatures reaching up to 67oC close to the slopes of the pile. Several methods for the determination of pyrite oxidation rate (POR) in waste rock have been compared and evaluated. Methods based on data collected in situ such as the interpretation of oxygen concentration profiles in waste rock pile and pyrite concentrations in solid phase were compared with the oxygen consumption method (OCM) in the laboratory. Analytical 1-D solution based on oxygen and temperature profiles in the pile was used for preliminary determination of POR. Analytical modeling results were used as an input for 2-D numerical model using TOUGH AMD. POR values based on pyrite mass balance (PMB) in solid phase were also calculated, assuming that average pyrite content in the deep, almost non-oxidized zone of the pile represents pre-oxidation conditions. Calculations were performed for prismatic columns with 1 m2 base. An approach based on dissolved sulfate mass balance was not used because of the lack of data from early stage of the pile and the non-conservative behavior of sulfate (precipitation of gypsum and jarosite in the pile). Finally, the oxygen consumption method (OCM) in the laboratory was based on oxygen concentration decline in headspace of closed chamber, where samples of waste rock sprinkled by water were located. Both fresh samples from mining operation and partially weathered samples collected in the pile were used. A range of POR values (mol(O2).kg-1.s-1) were obtained from the various methods. At Site 6 on the slope of the pile

  18. Influence of Chemical Piles on Convective Structure and the Geoid from 3D Spherical Mantle Convection Models

    NASA Astrophysics Data System (ADS)

    Liu, X.; Zhong, S.

    2013-12-01

    Classic mantle dynamic models for the Earth's geoid are mostly based on whole mantle convection and constrain that the upper mantle is significantly weaker than the lower mantle. Whole mantle convection models with such mantle viscosity structure have successfully explained the long-wavelength structure in the mantle. However, with increasing consensus on the existence of chemically distinct piles above the core mantle boundary (CMB) (also known as large low shear velocity provinces or LLSVPs), questions arise as to what extent the chemical piles influence the Earth's geoid and long-wavelength mantle convection. Some recent studies suggested that the chemical piles have a controlling effect on the Earth's degree two mantle structure, geoid, and true polar wander, although the chemical piles are estimated to be of small volume (~2% of the whole mantle) by seismic studies. We have formulated dynamically consistent 3D mantle convection models using CitcomS and studied how the chemical piles above CMB influence the long-wavelength convective structure and geoid. The models have free slip boundary conditions and temperature dependent viscosity. By comparing with purely thermal convection models, we found that the long wavelength convective structure is not sensitive to the presence of the chemical piles. By determining the geoid from the buoyance of a certain layer of the mantle, we found that for both purely thermal and thermochemical convection, the geoid is mostly contributed by the upper part of the mantle, with ~80% geoid explained by the buoyancy in the upper half of the mantle. In purely thermal convection, the contribution to the geoid from the bottom layer of the mantle always has the same sign with the total geoid (a bottom ~ 600 km thick layer gives ~3.5% of the total geoid). However, in the thermochemical convection, the bottom layer with overall negatively buoyant chemical piles gives rise to the geoid that has opposite sign with the total geoid and has a

  19. Effect of dislocation pile-up on size-dependent yield strength in finite single-crystal micro-samples

    SciTech Connect

    Pan, Bo; Shibutani, Yoji; Zhang, Xu; Shang, Fulin

    2015-07-07

    Recent research has explained that the steeply increasing yield strength in metals depends on decreasing sample size. In this work, we derive a statistical physical model of the yield strength of finite single-crystal micro-pillars that depends on single-ended dislocation pile-up inside the micro-pillars. We show that this size effect can be explained almost completely by considering the stochastic lengths of the dislocation source and the dislocation pile-up length in the single-crystal micro-pillars. The Hall–Petch-type relation holds even in a microscale single-crystal, which is characterized by its dislocation source lengths. Our quantitative conclusions suggest that the number of dislocation sources and pile-ups are significant factors for the size effect. They also indicate that starvation of dislocation sources is another reason for the size effect. Moreover, we investigated the explicit relationship between the stacking fault energy and the dislocation “pile-up” effect inside the sample: materials with low stacking fault energy exhibit an obvious dislocation pile-up effect. Our proposed physical model predicts a sample strength that agrees well with experimental data, and our model can give a more precise prediction than the current single arm source model, especially for materials with low stacking fault energy.

  20. Soil-water coupling finite element analysis on seismic enhancement effect of group-pile foundation with ground improvement

    NASA Astrophysics Data System (ADS)

    Zhang, F.; Jin, Y.; Bao, X.; Kondo, Y.; Nakamura, K.

    2010-06-01

    In this paper, soil-water coupling finite element analyses on a real-scale field test of 9-pile foundation subjected to horizontal cyclic loading is conducted at first using a program named as DBLEAVES (Ye, 2007). In the analysis, nonlinear behaviors of ground and piles are described by cyclic mobility model (Zhang et al, 2007) and axial force dependent model (AFD model) proposed by Zhang and Kimura (2002) which can take into consideration of axial-force dependency in the nonlinear moment-curvature relations. After the applicability of the proposed numerical method is verified by comparing the numerical results with the field test results, numerical experiments on seismic enhancement effect of group-pile foundation with ground improvement are conducted both in static loading and dynamic loading. In finding out the optimum pattern of ground improvement around existing pile foundation, three influential factors are considered in the numerical experiments, that is, the size, the location and the shape of ground-improvement zone around the pile group.

  1. Ostéosynthèse des fractures des métacarpiens et des phalanges de la main par mini plaque: à propos de 12 cas

    PubMed Central

    Moncef, Erraji; Abdelhafid, Derfoufi; Abdessamad, Kharraji; Omar, Agoumi; Najib, Abdeljaouad; Abdelkrim, Daoudi; Hicham, Yacoubi

    2016-01-01

    Le traitement des fractures instables des métacarpes et des phalanges reste un objet de controverse. Peu de séries ont été rapportées dans la littérature, rendant leur analyse difficile. Nous rapportons une étude rétrospective comportant 12 patients, opérés par cette technique, ayant eu des fractures déplacées des métacarpes ou des phalanges, sur une période de deux ans. Les résultats globaux ont été bons dans 75% des cas, moyenne dans 16,5% des cas et mauvais dans 8,5% des cas. La stabilité du montage par mini plaques des fractures instables des métacarpiens et des phalanges ont permis une mobilisation précoce des articulations de la main, évitant ainsi la raideur. PMID:27800079

  2. Emission factors for fugitive dust from bulldozers working on a coal pile.

    PubMed

    Mueller, Stephen F; Mallard, Jonathan W; Mao, Qi; Shaw, Stephanie L

    2015-01-01

    A study of a Powder River Basin (PRB) coal pile found that fugitive emissions from natural and human activity each produced similar levels of downwind fine + coarse (i.e., smaller than 10 µm, or PM10) particle mass concentrations. Natural impacts were statistically removed from downwind measurements to estimate emission factor Ev for bulldozers working on the pile. The Ev determined here was similar in magnitude to emission factors (EFs) computed using a U.S. Environmental Protection Agency (EPA) formulation for unpaved surfaces at industrial sites, even though the latter was not based on data for coal piles. EF formulations from this study and those in the EPA guidance yield values of similar magnitude but differ in the variables used to compute Ev variations. EPA studies included effects of surface silt fraction and vehicle weight, while the present study captured the influence of coal moisture. Our data indicate that the relationship between PRB coal fugitive dust Ev (expressed as mass of PM10 emitted per minute of bulldozer operation) and coal moisture content Mc (in percent) at the study site is best expressed as Ev =10(f(Mc())) where f(Mc) is a function of moisture. This function was determined by statistical regression between log10(Ev) and Mc where both Ev and Mc are expressed as daily averages of observations based on 289 hours sampled during 44 days from late June through mid-November of 2012. A methodology is described that estimates Mc based on available meteorological data (precipitation amount and solar radiation flux). An example is given of computed variations in daily Ev for an entire year. This illustrates the sensitivity of the daily average particulate EF to meteorological variability at one location. Finally, a method is suggested for combining the moisture-sensitive formulation for Ev with the EPA formulation to accommodate a larger number of independent variables that influence fugitive emissions.

  3. Formation of Saturn's F ring by collision between rubble-pile satellites

    NASA Astrophysics Data System (ADS)

    Hyodo, Ryuki; Ohtsuki, Keiji

    2014-11-01

    Saturn’s F ring is located just outside the Roche limit. This pure icy ring is radially narrow and is thought to be dynamically young. Two shepherding satellites, inner Pandora and outer Prometheus, confine and regulate its current dynamical evolution. The bulk density of these satellites is lower than that of rigid water ice, thus they are likely to be rubble-pile bodies. Crida & Charnoz (2012) showed that Saturn’s inner major satellites are formed by spreading of ancient massive rings through the Roche limit using one-dimensional analytical model. Recently, we have performed N-body simulations of the evolution of circumplanetary particle disks initially confined within a planet’s Roche limit, and showed that rubble-pile co-orbital satellites are often formed just outside the Roche limit (Hyodo et al, submitted). However, these co-orbital satellites are not always stable but can experience collisions between them. In addition, at radial locations barely outside the Roche limit, accretion efficiency is not 100%, and collision between aggregates can lead to complete or partial disruption (Karjalainen 2007, Hyodo & Ohtsuki 2014).In the present work, we perform local N-body simulations in the Hill coordinate system and investigate collisional disruption of rubble-pule satellites just outside the Roche limit corresponding to the location of Saturn’s F ring. We find that in some cases, collision between two aggregates results in partial disruption such that the dispersed particles are distributed between the two remnant satellites with small radial extent. Our results suggest that the F ring is a relic of collisional disruption between rubble-pile satellites formed at the last stage of the formation of inner major satellites as the rings spread across the Roche limit.

  4. Modulation of Gonococcal Piliation by Regulatable Transcription of pilE

    PubMed Central

    Long, Cynthia D.; Hayes, Stanley F.; van Putten, Jos P. M.; Harvey, Hillery A.; Apicella, Michael A.; Seifert, H. Steven

    2001-01-01

    The gonococcal pilus, a member of the type IV family of pili, is composed of numerous monomers of the pilin protein and plays an important role in the initiation of disease by providing the primary attachment of the bacterial cell to human mucosal tissues. Piliation also correlates with efficient DNA transformation. To investigate the relationships between these pilus-related functions, the piliation state, and the availability of pilin, we constructed a derivative of MS11-C9 (ΔpilE1) in which the lacIOP regulatory sequences control pilE transcription. In this strain, MS11-C9.10, the steady-state levels of pilin mRNA and protein directly correlate with the concentration of IPTG (isopropyl-β-d-thiogalactopyranoside) in the growth medium and can reach near-wild-type levels of expression. Transmission electron microscopy (TEM) demonstrated that the number of pili per cell correlated with the steady-state expression levels: at a low level of transcription, single long pili were observed; at a moderate expression level, many singular and bundled pili were expressed; and upon full gene expression, increased lateral association between pili was observed. Analysis of pilus assembly by TEM and epithelial cell adherence over a time course of induction demonstrated that pili were expressed as early as 1 h postinduction. Analysis at different steady-state levels of transcription demonstrated that DNA transformation efficiency and adherence of MS11-C9.10 to transformed and primary epithelial cells also correlated with the level of piliation. These data show that modulation of the level of pilE transcription, without a change in pilE sequence, can alter the number of pili expressed per cell, pilus bundling, DNA transformation competence, and epithelial cell adherence of the gonococcus. PMID:11160091

  5. Simulations of dislocation pile-ups at assymetric tilt boundaries in aluminum

    SciTech Connect

    Valone, Steven; Wang, Jian M; Hoagland, Richard C; Germann, Timothy C

    2011-01-21

    Materials deformation processes are increasingly approachable through the both conventional and accelerated molecular dynamics. In one deformation process, dislocation pile-up at a grain boundary, a greater understanding is required as to how dislocations transmit through grain boundaries, causing plastic deformation, or reflect and reconstruct the grain boundary, but with no macroscopic deformation. Here dislocation pile-ups in an alwninum bicrystal with an asymmetric tilt grain boundary are simulated atomistically, introducing effects of dislocation interactions beyond linear elastic ones. The observed responses as functions of the number of explicitly modeled dislocations and the magnitude of the applied stress are discussed. Typical conditions for the simulations consist of thermal relaxation room temperature, five active dislocations inserted within a 6.5-million-atom cell, and an additional fourteen dislocations represented within the atomistic simulation by their elastic strain fields. The dislocations are initially distributed according to linear elastic estimates of their positions in a double-ended pile-up from a chosen far-field stress. The whole cell is allowed to relax according to a procedure to be described. In the ensuing simulations, the system is propagated for some substantial period of time (lOs of ps), followed by small increments of strain. After a number of such increments, we observe all of the anticipated events. Usually several of the closest dislocations are absorbed into the grain boundary, resulting in varying amounts of reconstruction. Reflections from the boundary are common and show a strong dependence on sample thickness. Transmission events are seen on both slip systems in the other grain. The particulars of these events will be described as well.

  6. A Geophysical Laboratory for Rubble Pile Asteroids: The BASiX Mission

    NASA Astrophysics Data System (ADS)

    Scheeres, Daniel J.; Chesley, Steven; Anderson, Robert C.

    2014-11-01

    Small rubble pile asteroids exhibit a diverse range of evolutionary behaviors and morphologies, driven by an array of poorly understood geophysical effects. The complex ways that these bodies evolve belies their simple structure: gravitational aggregates of shattered primitive bodies. Their evolution can be dramatic, such as seen in the active asteroids P/2013 P5 and P/2013 R3, or may be subtly masked, such as in the tide-BYORP equilibria of singly-synchronous binary asteroids. Their evolutionary outcomes can defy the imagination, such as asteroid 1950 DA which is spinning faster than its gravitational attraction yet is held together by weak van der Waals forces (Rozitis et al. 2014), or present us with profound mysteries, such as how the Almahata Sitta meteorite could be comprised of such diverse components. Beyond these motivations, the study of rubble pile asteroid geophysics can shed insight into any solar system environment where gravitational aggregates interact in a micro-gravity setting, ranging from the protoplanetary disc to planetary ring systems. The broad study of the geophysics of aggregates in such micro-gravity environments is becoming both a unifying theme and emerging field of study. Out of the many diverse and complex forms that rubble pile asteroids take on, the study of NEA binary asteroids can in particular be used to expose the geophysics of micro-gravity aggregates. Binaries are an expression of micro-gravity geophysics due to the manner in which they form and their continuing evolution. Due to our ability to visit, probe and interact with NEA, we can also turn them into geophysical laboratories. This talk will introduce the science of the Binary Asteroid in-situ Explorer (BASiX) Discovery mission, which proposes to turn the primitive C-Type binary asteroid (175706) 1996 FG3 into such a geophysical laboratory. Exploring this body enables us to probe a broad range of rubble pile asteroid properties: internal tidal dissipation (through FG3

  7. Trigger-less readout system with pulse pile-up recovery for the PANDA electromagnetic calorimeter

    NASA Astrophysics Data System (ADS)

    Kavatsyuk, M.; Tambave, G.; Hevinga, M.; Lemmens, P. J. J.; Schakel, P.; Schreuder, F.; Speelman, R.; Löhner, H.; Panda Collaboration

    2013-08-01

    A simple, efficient, and robust on-line data-processing scheme was developed for the digital front-end electronics of the electromagnetic calorimeter of the PANDA spectrometer at FAIR, Darmstadt. The implementation of the processing algorithm in FPGA enables the construction of an almost dead-time free data acquisition system. The prototype of a complete trigger-less readout chain has been developed and evaluated. The precision of time synchronisation commands has been verified. A pile-up recovery algorithm was developed and evaluated over a large dynamic range of signal amplitudes.

  8. Annealed and quenched disorder in sand-pile models with local violation of conservation.

    PubMed

    Moghimi-Araghi, Saman; Sebtosheikh, Mahmoud

    2015-08-01

    In this paper we consider the Bak, Tang, and Wiesenfeld (BTW) sand-pile model with local violation of conservation through annealed and quenched disorder. We have observed that the probability distribution functions of avalanches have two distinct exponents, one of which is associated with the usual BTW model and another one which we propose to belong to a new fixed point; that is, a crossover from the original BTW fixed point to a new fixed point is observed. Through field theoretic calculations, we show that such a perturbation is relevant and takes the system to a new fixed point. PMID:26382353

  9. Recovery of barotrauma injuries resulting from exposure to pile driving sound in two sizes of hybrid striped bass.

    PubMed

    Casper, Brandon M; Halvorsen, Michele B; Matthews, Frazer; Carlson, Thomas J; Popper, Arthur N

    2013-01-01

    The effects of loud sounds on fishes, such as those produced during impulsive pile driving, are an increasing concern in the management of aquatic ecosystems. However, very little is known about such effects. Accordingly, a High Intensity Controlled Impedance Fluid Filled wave Tube (HICI-FT) was used to investigate the effects of sounds produced by impulsive pile driving on two size groups of hybrid striped bass (white bass Moronechrysops x striped bass Moronesaxatilis). The larger striped bass (mean size 17.2 g) had more severe injuries, as well as more total injuries, than the smaller fish (mean size 1.3 g). However, fish in each size group recovered from most injuries within 10 days of exposure. A comparison with different species from previously published studies show that current results support the observation that fishes with physoclistous swim bladders are more susceptible to injury from impulsive pile driving than are fishes with physostomous swim bladders.

  10. Thermal-Hydraulics and Electrochemistry of a Boiling Solution in a Porous Sludge Pile A Test Methodology

    SciTech Connect

    R.F. Voelker

    2001-05-03

    When boiling occurs in a pile of porous corrosion products (sludge), chemical species can concentrate. These species can react with the corrosion products and transform the sludge into a rock hard mass and/or create a corrosive environment. In-situ measurements are required to improve the understanding of this process, and the thermal-hydraulic and electrochemical environment in the pile. A test method is described that utilizes a water heated instrumented tube array in an autoclave to perform the in-situ measurements. As a proof of method feasibility, tests were performed in an alkaline phosphate solution. The test data is discussed. Temperature changes and electrochemical potential shifts were used to indicate when chemicals concentrate and if/when the pile hardens. Post-test examinations confirmed hardening occurred. Experiments were performed to reverse the hardening process. A one-dimensional model, utilizing capillary forces, was developed to understand the thermal-hydraulic measurements.

  11. Recovery of barotrauma injuries resulting from exposure to pile driving sound in two sizes of hybrid striped bass.

    PubMed

    Casper, Brandon M; Halvorsen, Michele B; Matthews, Frazer; Carlson, Thomas J; Popper, Arthur N

    2013-01-01

    The effects of loud sounds on fishes, such as those produced during impulsive pile driving, are an increasing concern in the management of aquatic ecosystems. However, very little is known about such effects. Accordingly, a High Intensity Controlled Impedance Fluid Filled wave Tube (HICI-FT) was used to investigate the effects of sounds produced by impulsive pile driving on two size groups of hybrid striped bass (white bass Moronechrysops x striped bass Moronesaxatilis). The larger striped bass (mean size 17.2 g) had more severe injuries, as well as more total injuries, than the smaller fish (mean size 1.3 g). However, fish in each size group recovered from most injuries within 10 days of exposure. A comparison with different species from previously published studies show that current results support the observation that fishes with physoclistous swim bladders are more susceptible to injury from impulsive pile driving than are fishes with physostomous swim bladders. PMID:24040089

  12. Soil-structure Interaction in the Seismic Response of Coupled Wall-frame Structures on Pile Foundations

    SciTech Connect

    Carbonari, S.; Dezi, F.; Leoni, G.

    2008-07-08

    This paper presents a study on the seismic response of coupled wall-frame structures founded on piles. A complete soil-structure interaction analysis is carried out with reference to a case study. Three different soils and seven real accelerograms are considered. Local site response analyses are performed in order to evaluate the incoming free-field motion at different depths and the ground motion amplifications. A numerical model, accounting for the pile-soil-pile interaction and for material and radiation damping, is used to evaluate the impedance matrix and the foundation input motion. The domain decomposition technique is adopted to perform time-domain seismic analyses introducing Lumped Parameter Models to take into account the impedance of the soil-structure system. Applications show that the rocking phenomena affect the behaviour of the structure by changing the base shear distribution within the wall and the frame and by increasing the structural displacements.

  13. Model Experiments and Elasto-Plastic Finite Element Analysis about Seepage Failure of Sand Behind Fixed Sheet Pile

    NASA Astrophysics Data System (ADS)

    Okajima, Kenji; Tanaka, Tadatsugu; Zhang, Shanji; Komatsu, Takahiro

    Constructing civil engineering structures, temporaly or permanent water proofing sheet piles often are used. The stability of seepage failure are carefully applied to those sheet piles, although many troubles of seepage failure were reported. On this problem the predictive method of the deformation and critical water head is required. In this study we carried out the model experiments which were designed for studying the seepage failure of soil behind fixed sheet piles and our elasto-plastic finite element method was applied to verify the effectiveness. Terzaghi method is very famous method for this problem and Terzaghi method was investigated by experiments data. As a result, it was confirmed that elasto-plastic finite element method was effectiveness and Terzaghi method was useful for this problem.

  14. Assessing underwater noise levels during pile-driving at an offshore windfarm and its potential effects on marine mammals.

    PubMed

    Bailey, Helen; Senior, Bridget; Simmons, Dave; Rusin, Jan; Picken, Gordon; Thompson, Paul M

    2010-06-01

    Marine renewable developments have raised concerns over impacts of underwater noise on marine species, particularly from pile-driving for wind turbines. Environmental assessments typically use generic sound propagation models, but empirical tests of these models are lacking. In 2006, two 5MW wind turbines were installed off NE Scotland. The turbines were in deep (>40m) water, 25km from the Moray Firth Special Area of Conservation (SAC), potentially affecting a protected population of bottlenose dolphins. We measured pile-driving noise at distances of 0.1 (maximum broadband peak to peak sound level 205dB re 1microPa) to 80km (no longer distinguishable above background noise). These sound levels were related to noise exposure criteria for marine mammals to assess possible effects. For bottlenose dolphins, auditory injury would only have occurred within 100m of the pile-driving and behavioural disturbance, defined as modifications in behaviour, could have occurred up to 50km away.

  15. Effect of horizontal vibration on pile of cylinder avalanches as a pseudo-two dimensional granular system

    NASA Astrophysics Data System (ADS)

    Mardiansyah, Y.; Yulia; Khotimah, S. N.; Suprijadi; Viridi, S.

    2016-08-01

    Dynamics of pseudo-two dimensional granular material consisted of two layers cylinder piles positioned on top of a horizontally vibrated plate is reported in this work. It is aimed to observe structural change of the cylinder pile vibrated in certain frequency and amplitude. Dimensionless acceleration Γ= 4π2f2A/g (with g is gravitational acceleration), which is generally used in granular materials to observe transition between states, e.g. stable, rotating without slipping, rolling and slipping in Γ-f plane, does not work well for this system. For this system additional states for the piles can also be observed, e.g. stable and flowing states. Observations parameters are frequency f (measured in Hz) and amplitude A (measured in cm). These parameters are used to construct the A-f plane instead of Γ-f one.

  16. DEVELOPMENT OF DUAL ANCHORED SHEET PILE WALL METHOD TO INCREASE FRONT WATER DEPTH AND SEISMIC RESISTANCE OF EXISTING QUAY

    NASA Astrophysics Data System (ADS)

    Nakamura, Yasushi; Sato, Masakatsu; Kikuchi, Yoshiaki; Sugano, Takahiro; Morikawa, Yoshiyuki; Hoshino, Masami; Miki, Kenichi

    Recently the dual anchored sheet pile wall method has been developed to increase a front water depth and seismic resistance of existing quay walls by providing an additional anchor in the lower level of them to reduce a flexural moment of the sheet piles and a tension of the anchors. The existing technical information is not enough to evaluate the seismic behavior and the retrofit of the quay walls with anchors at two different levels. Therefore the experiments with a scale model set on the vibration table of the centrifugal apparatus as well as two dimensional effective stress analyses have been mobilized to investigate the seismic retrofit of the dual anchored sheet pile wall. The experiments and analyses demonstrate the increase the earthquake resistance of quay walls, because they showed the additional anchor can reduce the stress of the sheet walls to one half.

  17. Recovery of Barotrauma Injuries Resulting from Exposure to Pile Driving Sound in Two Sizes of Hybrid Striped Bass

    PubMed Central

    Matthews, Frazer; Carlson, Thomas J.; Popper, Arthur N.

    2013-01-01

    The effects of loud sounds on fishes, such as those produced during impulsive pile driving, are an increasing concern in the management of aquatic ecosystems. However, very little is known about such effects. Accordingly, a High Intensity Controlled Impedance Fluid Filled wave Tube (HICI-FT) was used to investigate the effects of sounds produced by impulsive pile driving on two size groups of hybrid striped bass (white bass Moronechrysops x striped bass Moronesaxatilis). The larger striped bass (mean size 17.2 g) had more severe injuries, as well as more total injuries, than the smaller fish (mean size 1.3 g). However, fish in each size group recovered from most injuries within 10 days of exposure. A comparison with different species from previously published studies show that current results support the observation that fishes with physoclistous swim bladders are more susceptible to injury from impulsive pile driving than are fishes with physostomous swim bladders. PMID:24040089

  18. PileLineGUI: a desktop environment for handling genome position files in next-generation sequencing studies

    PubMed Central

    López-Fernández, Hugo; Glez-Peña, Daniel; Reboiro-Jato, Miguel; Gómez-López, Gonzalo; Pisano, David G.; Fdez-Riverola, Florentino

    2011-01-01

    Next-generation sequencing (NGS) technologies are making sequence data available on an unprecedented scale. In this context, new catalogs of Single Nucleotide Polymorphism and mutations generated by resequencing studies are usually stored in genome position files (e.g. Variant Call Format, SAMTools pileup, BED, GFF) comprising of large lists of genomic positions, which are difficult to handle by researchers. Here, we present PileLineGUI, a novel desktop application primarily designed for manipulating, browsing and analysing genome position files (GPF), with specific support to somatic mutation finding studies. The developed tool also integrates a new genome browser module specially designed for inspecting GPFs. PileLineGUI is free, multiplatform and designed to be intuitively used by biomedical researchers. PileLineGUI is available at: http://sing.ei.uvigo.es/pileline/pilelinegui.html. PMID:21646339

  19. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  20. Cancer risk in DES daughters

    PubMed Central

    Verloop, Janneke; van Leeuwen, Flora E.; Helmerhorst, Theo J. M.; van Boven, Hester H.

    2010-01-01

    Objective We examined long-term risk of cancer in women exposed to diethylstilbestrol (DES) in utero. Methods A total of 12,091 DES-exposed women in the Netherlands were followed prospectively from December 1992 till June 2008. Cancer incidence was assessed through linkage with the Dutch pathology database (PALGA) and the Netherlands Cancer Registry and compared with the Dutch female population. Results A total of 348 medically verified cancers occurred; median age at end of follow-up was 44.0 years. No overall increased risk of cancer was found (standardized incidence ratio [SIR] = 1.01; 95% confidence interval [CI] = 0.91, 1.13). The risk of clear cell adenocarcinoma of the vagina and cervix (CCA) was statistically significantly increased (SIR = 24.23; 95% CI = 8.89, 52.74); the elevated risk persisted above 40 years of age. The risk of melanoma diagnosed before age 40 was increased (SIR = 1.59; 95% CI = 1.08, 2.26). No excess risks were found for other sites, including breast cancer. Conclusions Except for an elevated risk of CCA, persisting at older ages, and an increased risk of melanoma at young ages, we found no increased risk of cancer. Longer follow-up is warranted to examine cancer risk at ages when cancer occurs more frequently. Electronic supplementary material The online version of this article (doi:10.1007/s10552-010-9526-5) contains supplementary material, which is available to authorized users. PMID:20204493

  1. The enhancement of existing DES Maplet interface

    NASA Astrophysics Data System (ADS)

    Abdullah, Nur Lina; Mutalip, Rasidah Abdull; Abdullah, Kamilah

    2014-07-01

    This study pertains to the process of Data Encryption Standard, DES. DES consists of encryption and decryption processes linked with mathematical elements such as algebra and number theory. Preliminary, studies revealed that most of mathematics students face a problem in understanding the complicated process of DES. In modern learning methods, learning environment becomes more interesting with the use of computer and a variety of mathematical software packages. Several mathematical softwares such as Maple, Mathematica, Mathlab and Sage were developed in order to fulfill the specific calculation requirements. Correspondingly, motivated from that, this study incorporated with Maple to enhance the existing DES Maplet interface to be more interactive and user-friendly compared to the original version.

  2. Prevalence and genetic diversity of two adhesion-related genes, pilE and nadA, in Neisseria meningitidis in China.

    PubMed

    Sun, X; Zhou, H; Xu, L; Yang, H; Gao, Y; Zhu, B; Shao, Z

    2013-10-01

    The main Neisseria meningitidis adhesion molecules, type IV pili (Tfp) and Neisseria adhesion A (NadA), play important roles in the pathogenesis of invasive meningococcal disease. PilE is the major Tfp subunit. In this study, the prevalence and genetic diversity of pilE and nadA were investigated in the prevalent serogroups and clonal complexes (CC) of N. meningitidis isolated in China. All serogroup A strains belonging to CC1 and CC5 and all CC11 serogroup W135 strains were clustered into class II PilE clades. All serogroup C and most of serogroup B isolates except CC8 and ST5642 were class I PilE clades. Class II pilE sequences were highly conserved. All isolates belonging to class I PilE isolates were nadA negative. However, nadA-positive strains were exclusively found in CC5 and CC11 isolates (class II PilE). This study showed that PilE and NadA may be related to epidemic or endemic meningococcal disease.

  3. Sources of acid and metals from the weathering of the Dinero waste pile, Lake Fork watershed, Leadville, Colorado

    USGS Publications Warehouse

    Diehl, S.F.; Hageman, Phil L.; Smith, Kathleen S.; Herron, J.T.; Desborough, G.A.

    2005-01-01

    Two trenches were dug into the south Dinero mine-waste pile near Leadville, Colorado, to study the weathering of rock fragments and the mineralogic sources of metal contaminants in the surrounding wetland and Lake Fork Watershed. Water seeping from the base of the south Dinero waste-rock pile was pH 2.9, whereas leachate from a composite sample of the rock waste was pH 3.3. The waste pile was mostly devoid of vegetation, open to infiltration of precipitation, and saturated at the base because of placement in the wetland. The south mine-waste pile is composed of poorly sorted material, ranging from boulder-size to fine-grained rock fragments. The trenches showed both matrix-supported and clast-supported zones, with faint horizontal color banding, suggesting zonation of Fe oxides. Secondary minerals such as jarosite and gypsum occurred throughout the depth of the trenches. Infiltration of water and transport of dissolved material through the pile is evidenced by optically continuous secondary mineral deposits that fill or line voids. Iron-sulfate material exhibits microlaminations with shrinkage cracking and preferential dissolution of microlayers that evidence drying and wetting events. In addition to fluids, submicron-sized to very fine-grained particles such as jarosite are transported through channel ways in the pile. Rock fragments are coated with a mixture of clay, jarosite, and manganese oxides. Dissolution of minerals is a primary source of metals. Skeletal remnants of grains, outlined by Fe-oxide minerals, are common. Potassium jarosite is the most abundant jarosite phase, but Pb-and Ag-bearing jarosite are common. Grain-sized clusters of jarosite suggest that entire sulfide grains were replaced by very fine-grained jarosite crystals. The waste piles were removed from the wetland and reclaimed upslope in 2003. This was an opportunity to test methods to identify sources of acid and metals and metal transport processes within a waste pile. A series of

  4. Effects of exposure to pile-driving sounds on the lake sturgeon, Nile tilapia and hogchoker.

    PubMed

    Halvorsen, Michele B; Casper, Brandon M; Matthews, Frazer; Carlson, Thomas J; Popper, Arthur N

    2012-12-01

    Pile-driving and other impulsive sound sources have the potential to injure or kill fishes. One mechanism that produces injuries is the rapid motion of the walls of the swim bladder as it repeatedly contacts nearby tissues. To further understand the involvement of the swim bladder in tissue damage, a specially designed wave tube was used to expose three species to pile-driving sounds. Species included lake sturgeon (Acipenser fulvescens)--with an open (physostomous) swim bladder, Nile tilapia (Oreochromis niloticus)--with a closed (physoclistous) swim bladder and the hogchoker (Trinectes maculatus)--a flatfish without a swim bladder. There were no visible injuries in any of the exposed hogchokers, whereas a variety of injuries were observed in the lake sturgeon and Nile tilapia. At the loudest cumulative and single-strike sound exposure levels (SEL(cum) and SEL(ss) respectively), the Nile tilapia had the highest total injuries and the most severe injuries per fish. As exposure levels decreased, the number and severity of injuries were more similar between the two species. These results suggest that the presence and type of swim bladder correlated with injury at higher sound levels, while the extent of injury at lower sound levels was similar for both kinds of swim bladders.

  5. An innovative acoustic sensor for first in-pile fission gas release determination - REMORA 3 experiment

    SciTech Connect

    Rosenkrantz, E.; Ferrandis, J. Y.; Augereau, F.; Lambert, T.; Fourmentel, D.; Tiratay, X.

    2011-07-01

    A fuel rod has been instrumented with a new design of an acoustic resonator used to measure in a non destructive way the internal rod plenum gas mixture composition. This ultrasonic sensor has demonstrated its ability to operate in pile during REMORA 3 irradiation experiment carried out in the OSIRIS Material Testing Reactor (CEA Saclay, France). Due to very severe experimental conditions such as temperature rising up to 150 deg.C and especially, high thermal fluence level up to 3.5 10{sup 19} n.cm{sup 2}, the initial sensor gas speed of sound efficiency measurement was strongly reduced due to the irradiation effects on the piezo-ceramic properties. Nevertheless, by adding a differential signal processing method to the initial data analysis procedure validated before irradiation, the gas resonance peaks were successfully extracted from the output signal. From these data, the molar fractions variations of helium and fission gas were measured from an adapted Virial state equation. Thus, with this sensor, the kinetics of gas release inside fuel rods could be deduced from the in-pile measurements and specific calculations. These data will also give information about nuclear reaction effect on piezo-ceramics sensor under high neutron and gamma flux. (authors)

  6. Can acoustic emissions patterns signal imminence of avalanche events in a growing sand pile?

    NASA Astrophysics Data System (ADS)

    Vögtli, Melanie; Lehmann, Peter; Breitenstein, Daniel; Or, Dani

    2014-05-01

    Gravity driven mass release is often triggered abruptly with limited precursory cues to indicate imminent failure and thus limiting early warning. Evidence suggests that with increased mechanical loading of a slope, numerous local damage events marking friction between rearranged particles or breakage of roots release strain energy as elastic waves measurable as acoustic emissions. We examined the potential predictability of mass release events from preceding acoustic emission (AE) signatures in a well-known and simple model system of a growing sand pile. We installed four AE-sensors within the core of a 30 cm (diameter) sand pile fed by a constant input of grains and mounted on a balance. Subsequent to the convergence of the slope to dynamic angle of repose, sand avalanche across the bottom boundary were monitored by abrupt mass change and by the amplitudes and number of AE events (recorded at high frequency and averaged to 0.2 s). We detected a systematic change of AE-patterns characterized by systematically decreasing AE standard deviation prior to each mass release. Although the lead time following minimum AE standard deviation was relatively short (10s of seconds), the AE signature already started to change minutes before the mass release. Accordingly the information embedded in AE signal dynamics could potentially offer larger lead times for systems of practical interest.

  7. Metal binding by bacteria from uranium mining waste piles and its technological applications.

    PubMed

    Pollmann, K; Raff, J; Merroun, M; Fahmy, K; Selenska-Pobell, S

    2006-01-01

    Uranium mining waste piles, heavily polluted with radionuclides and other toxic metals, are a reservoir for bacteria that have evolved special strategies to survive in these extreme environments. Understanding the mechanisms of bacterial adaptation may enable the development of novel bioremediation strategies and other technological applications. Cell isolates of Bacillus sphaericus JG-A12 from a uranium mining waste pile in Germany are able to accumulate high amounts of toxic metals such as U, Cu, Pb, Al, and Cd as well as precious metals. Some of these metals, i.e. U, Cu, Pd(II), Pt(II) and Au(III), are also bound by the highly orderd paracrystalline proteinaceous surface layer (S-layer) that envelopes the cells of this strain. These special capabilities of the cells and the S-layer proteins of B. sphaericus JG-A12 are highly interesting for the clean-up of uranium contaminated waste waters, for the recovery of precious metals from electronic wastes, and for the production of metal nanoclusters. The fabricated nanoparticles are promising for the development of novel catalysts. This work reviews the molecular biology of the S-layer of the strain JG-A12 and the S-layer dependent interactions of the bacterial cells with metals. It presents future perspectives for their application in bioremediation and nanotechnology.

  8. Software emulator of nuclear pulse generation with different pulse shapes and pile-up

    NASA Astrophysics Data System (ADS)

    Pechousek, Jiri; Konecny, Daniel; Novak, Petr; Kouril, Lukas; Kohout, Pavel; Celiktas, Cuneyt; Vujtek, Milan

    2016-08-01

    The optimal detection of output signals from nuclear counting devices represents one of the key physical factors that govern accuracy and experimental reproducibility. In this context, the fine calibration of the detector under diverse experimental scenarios, although time costly, is necessary. However this process can be rendered easier with the use of systems that work in lieu of emulators. In this report we describe an innovative programmable pulse generator device capable to emulate the scintillation detector signals, in a way to mimic the detector performances under a variety of experimental conditions. The emulator generates a defined number of pulses, with a given shape and amplitude in the form of a sampled detector signal. The emulator output is then used off-line by a spectrometric system in order to set up its optimal performance. Three types of pulse shapes are produced by our device, with the possibility to add noise and pulse pile-up effects into the signal. The efficiency of the pulse detection, pile-up rejection and/or correction, together with the dead-time of the system, are therein analyzed through the use of some specific algorithms for pulse processing, and the results obtained validate the beneficial use of emulators for the accurate calibration process of spectrometric systems.

  9. A simplified method for analysis of geosynthetic reinforcement used in pile supported embankments.

    PubMed

    Fei, Kang

    2014-01-01

    The inclusion of geosynthetic reinforcement in the piled embankment can help transfer loads to the piles and reduce total and differential settlements. In order to select the appropriate reinforcement material, the reasonable calculation of the deflection and tension is very important. Current design methods usually do not represent the true three-dimensional (3D) nature of the displacements, strains, and stresses of the geosynthetics, and the resulting error may be large and cannot be neglected in some cases. In this study, two- and three-dimensional finite element analyses were conducted to identify the behavior of geosynthetic reinforcement and investigate the accuracy of the assumptions made in the current design methods. Based on the numerical results, a new 3D deflected shape of the geosynthetic reinforcement was suggested, and then the corresponding governing equation was derived and solved based on the membrane theory. To investigate the validity of the proposed method, the predicted maximum deflection, deflection shape, and the developed tensile force of the geosynthetics have been compared with the experimental data collected from the literatures and finite element analysis results.

  10. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    PubMed

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness. PMID:25750056

  11. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    PubMed

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness.

  12. Relation between self-organized criticality and grain aspect ratio in granular piles

    NASA Astrophysics Data System (ADS)

    Denisov, D. V.; Villanueva, Y. Y.; Lőrincz, K. A.; May, S.; Wijngaarden, R. J.

    2012-05-01

    We investigate experimentally whether self-organized criticality (SOC) occurs in granular piles composed of different grains, namely, rice, lentils, quinoa, and mung beans. These four grains were selected to have different aspect ratios, from oblong to oblate. As a function of aspect ratio, we determined the growth (β) and roughness (α) exponents, the avalanche fractal dimension (D), the avalanche size distribution exponent (τ), the critical angle (γ), and its fluctuation. At superficial inspection, three types of grains seem to have power-law-distributed avalanches with a well-defined τ. However, only rice is truly SOC if we take three criteria into account: a power-law-shaped avalanche size distribution, finite size scaling, and a universal scaling relation relating characteristic exponents. We study SOC as a spatiotemporal fractal; in particular, we study the spatial structure of criticality from local observation of the slope angle. From the fluctuation of the slope angle we conclude that greater fluctuation (and thus bigger avalanches) happen in piles consisting of grains with larger aspect ratio.

  13. Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain.

    PubMed

    López-Coto, I; Mas, J L; Vargas, A; Bolívar, J P

    2014-09-15

    Nearly 1.0 × 10(8) tonnes of phosphogypsum were accumulated during last 50 years on a 1,200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by (226)Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bqm(-2)s(-1)) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bqm(-2)s(-1)). PMID:25194815

  14. A Simplified Method for Analysis of Geosynthetic Reinforcement Used in Pile Supported Embankments

    PubMed Central

    Fei, Kang

    2014-01-01

    The inclusion of geosynthetic reinforcement in the piled embankment can help transfer loads to the piles and reduce total and differential settlements. In order to select the appropriate reinforcement material, the reasonable calculation of the deflection and tension is very important. Current design methods usually do not represent the true three-dimensional (3D) nature of the displacements, strains, and stresses of the geosynthetics, and the resulting error may be large and cannot be neglected in some cases. In this study, two- and three-dimensional finite element analyses were conducted to identify the behavior of geosynthetic reinforcement and investigate the accuracy of the assumptions made in the current design methods. Based on the numerical results, a new 3D deflected shape of the geosynthetic reinforcement was suggested, and then the corresponding governing equation was derived and solved based on the membrane theory. To investigate the validity of the proposed method, the predicted maximum deflection, deflection shape, and the developed tensile force of the geosynthetics have been compared with the experimental data collected from the literatures and finite element analysis results. PMID:25215318

  15. Evolution of Piled Up Compressions in Modeled CME Sheaths and the Resulting Sheath Structures

    NASA Astrophysics Data System (ADS)

    Das, I.; Opher, M.; Evans, R. M.; Gombosi, T. I.

    2010-12-01

    We study Coronal Mass Ejection (CME) driven shocks and the resulting post shock structures in the lower corona (~ 2-7 Rsun). Two CMEs are erupted by modified Titov-Demoulin (TD) and Gibson-Low (GL) type flux ropes with Space Weather Modeling Framework. We observe a substantial pile up of density compression and a narrow region of plasma depletion layer (PDL) in the simulations. As the CME/flux rope moves and expands in solar wind medium, it pushes the magnetized material laying ahead of it. Hence, the magnetic field lines draping around the CME front are compressed in the sheath just ahead of the CME. These compressed field lines squeeze out the plasma sideways forming PDL in the region. Solar plasma being pushed and displaced from behind, forms a strong piled up compression (PUC) of density downstream of the PDL. Both CMEs have comparable propagation speeds while GL has larger expansion speed than TD due to its higher initial magnetic pressure. We argue that high CME expansion speed along with high solar wind density in the region are responsible for the large PUC found in the lower corona. In case of GL the PUC is much wider although the density compression ratio for both the cases are comparable. Although these simulations artificially initiate out-of-equilibrium CMEs and drive them in an artificial solar wind solution, we predict that PUCs, in general, will be large in the lower corona. This should affect the ion profiles of the accelerated solar energetic particles.

  16. Attenuation of contaminants of coal pile leachate by interaction with subsoil

    SciTech Connect

    Ghuman, G.S.; Denham, M.E.

    1996-09-01

    Increased use of coal as energy source has resulted in its greater outdoor storage at electrical generation sites. Coal pile runoff (CPR) with its high concentrations of Fe, Al and sulfate leaches into subsoil and may adversely affect the quality of groundwater. During the summer, 1995, this study was conducted to determine the removal of CPR contaminants by subsoil around D-area electric plant at Savannah River Site (SRS). Groundwater samples from five monitoring wells were analyzed for physical and chemical parameters. Hydrolab Surveyor, TOC Analyzer, Dionex Ion Chromatograph and ICP-ES instruments were used for analysis. Results showed appreciable removal of CPR contaminants, sulfate, Fe, Al, Cr, Mn and Ni by the upper subsoil near the pile. The reductions in the concentrations of major contaminants in the distant wells relative to the near wells were from 12,947 to 1293 mg/L for sulfate, from 3.138 to 42 mg/L for Fe, and from 593 to 119 mg/L for Al. The study revealed the capacity of soil system to retain toxic elements of CPR leachate, which may lead to remedial actions.

  17. Characterization of the graphite pile as a source of thermal neutrons

    NASA Astrophysics Data System (ADS)

    Vykydal, Zdenek; Králík, Miloslav; Jančář, Aleš; Kopecký, Zdeněk; Dressler, Jan; Veškrna, Martin

    2015-11-01

    A new graphite pile designed to serve as a standard source of thermal neutrons has been built at the Czech Metrology Institute. Actual dimensions of the pile are 1.95 m (W)×1.95 m (L)×2.0 m (H). At its center, there is a measurement channel whose dimensions are 0.4 m×0.4 m×1.25 m (depth). The channel is equipped with a calibration bench, which allows reproducible placement of the tested/calibrated device. At a distance of 80 cm from the channel axis, six holes are symmetrically located allowing the placement of radionuclide neutron sources of Pu-Be and/or Am-Be type. Spatial distribution of thermal neutron fluence in the cavity was calculated in detail with the MCNP neutron transport code. Experimentally, it was measured with two active detectors: a small 3He proportional detector by the French company LMT, type 0.5 NH 1/1 KF, and a silicon pixel detector Timepix with 10B converter foil. The relative values of thermal neutron fluence rate obtained with active detectors were converted to absolute ones using thermal neutron fluence rates measured by means of gold foil activation. The quality of thermal neutron field was characterized by the cadmium ratio.

  18. Cathodic polarization and protection of simulated prestressed concrete pilings in seawater

    SciTech Connect

    Pangrazzi, R. ); Hartt, W.H. . Center for Marine Materials); Kessler, R. . Florida Dept. of Transportation)

    1994-03-01

    Experiments were conducted to determine the effectiveness of localized cathodic polarization for reducing corrosion of simulated prestressed concrete piles containing continuous and segmented tendons exposed to seawater. Conductive rubber was used as the anode material. Corrosion of the steel was enhanced for most specimens by admixing calcium chloride (CaCl[sub 2]) during concrete pouring. Specimens were polarized cathodically at constant potentials (current on) ranging from [minus]0.72 V[sub SCE] to [minus]1.10 V[sub SCE]. The magnitude of impressed current and its distribution along the embedded steel were monitored as a function of exposure time and level of polarization. Potential distributions for the continuous and segmented tendons were measured also. The level of cathodic polarization was assessed as a function of position along the specimens by the depolarization method and by post-test visual inspection. Protection was achieved where instant-off potentials were more negative than [minus]0.75 V[sub SCE]. Polarization was negligible at heights > [approximately]1 dm above the anode. Results were presented within the context of protecting marine pilings from corrosion.

  19. Pile construction

    DOEpatents

    Johnson, Alfred A.; Carleton, John T.

    1978-05-02

    A graphite-moderated, water-cooled nuclear reactor including graphite blocks disposed in transverse alternate layers, one set of alternate layers consisting of alternate full size blocks and smaller blocks through which cooling tubes containing fuel extend, said smaller blocks consisting alternately of tube bearing blocks and support block, the support blocks being smaller than the tube bearing blocks, the aperture of each support block being tapered so as to provide the tube extending therethrough with a narrow region of support while being elsewhere spaced therefrom.

  20. Effets perturbateurs endocriniens des pesticides organochlores.

    PubMed

    Charlier, C; Plomteux, G

    2002-01-01

    Xenoestrogens such organochlorine pesticides are known to induce changes in reproductive development, function or behaviour in wildlife. Because these compounds are able to modify the estrogens metabolism, or to compete with estradiol for binding to the estrogen receptor, it may be possible that these products affect the risk of developing impaired fertility, precocious puberty or some kinds of cancer in man. Le plus ancien récit de lutte contre la pollution remonte à une légende indienne racontant que la divinité Sing-bonga était incommodée par les émanations des fours dans lesquels les Asuras fondaient leurs métaux (1). Evidemment depuis, la problématique n-a cessé de s-accroître et la contamination de la Terre par de nombreux polluants est devenue aujourd-hui un problème majeur de notre Société. La protection de notre environnement est une question capitale qui doit être respectée malgré la pression économique actuelle et qui ne cessera de croître au cours des prochaines années même si l-identification objective et indiscutable de ce qui est essentiel - donc devant être prioritairement garanti sur la planète - est difficile à cerner (2). « Un oiseau en mauvais état ne pond pas de bons oeufs » disait un proverbe grec. Mais ce n-est qu-à partir de la seconde moitié du XXème siècle que les toxicologues ont commencé à identifier les effets qu-avaient entraînés à l-échelle mondiale les pollutions émises aux XIXème siècle sur la faune sauvage et sur le cheptel (3). L-histoire contemporaine des pesticides industriels commence vers 1874 (synthèse des organochlorés) et se poursuit tout au long de ces 2 siècles en passant par la synthèse des organophosphorés (1950), des carbamates (1970) et des pyréthroïdes (1975) (4). Le dichlorodiphényltrichloroéthane (DDT) a été synthétisé pour la première fois par un étudiant en cours de préparation de sa thèse de doctorat : Othmer Zeidler. La production, reprise par les

  1. Biological control agent of larger black flour beetles (Coleoptera: Tenebrionidae): A nuisance pest developing in cotton gin trash piles.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Larger black flour beetles (LBFB), Cynaeus angustus, feed on saprophytic fungi found in gin trash piles, and become nuisance pests in homes and businesses. We examined the dose-response of three entomopathogenic nematode species (Steinernema carpocapsae, S. feltiae, and Heterorhabditis bacteriophora...

  2. Baseline restoration and pile-up correction based on bipolar cusp-like shaping for high-resolution radiation spectroscopy

    NASA Astrophysics Data System (ADS)

    Kafaee, Mahdi; Moussavi-Zarandi, Ali

    2016-04-01

    The baseline may shift in many radiation measurement systems. The shift is time variant and depends on the events. Also, with high count rates, pulses may overlap in random time intervals. These phenomena can affect the peak values of the pulses. Piled-up events are traditionally rejected, but this reduces the detection efficiency considerably. In other approaches, the corrupted events are reconstructed, and information about the single pulses is extracted. The peaks carry much of the basic information, so many shaping methods have been proposed so far. For pile-up mitigation, a narrow unipolar shaping is enough, but a baseline shift is eliminated by using bipolar shaping. However, the latter decreases the signal-to-noise ratio (SNR), which is critical for high-resolution spectroscopy. In this paper, we propose bipolar cusp-like shaping as a tradeoff between mitigating the baseline shift and pulse pile-up. A novel recursive algorithm, implementable on digital pulse processors (DPPs), is introduced and is then evaluated. Finally, the superior noise-reduction capability is studied by using Monte Carlo simulations, a real piled-up pulse stream shaped by using the algorithm, and the results show its advantages.

  3. 40 CFR 63.1343 - What standards apply to my kilns, clinker coolers, raw material dryers, and open clinker piles?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true What standards apply to my kilns... What standards apply to my kilns, clinker coolers, raw material dryers, and open clinker piles? (a) General. The provisions in this section apply to each kiln and any alkali bypass associated with that...

  4. 40 CFR 63.1343 - What standards apply to my kilns, clinker coolers, raw material dryers, and open clinker piles?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false What standards apply to my kilns... What standards apply to my kilns, clinker coolers, raw material dryers, and open clinker piles? (a) General. The provisions in this section apply to each kiln and any alkali bypass associated with that...

  5. A database of archived drilling records of the drill cuttings piles at the North West Hutton oil platform.

    PubMed

    Marsh, Roy

    2003-05-01

    Drill cuttings piles are found underneath several hundred oil platforms in the North Sea, and are contaminated with hydrocarbons and chemical products. This study characterised the environmental risk posed by the cuttings pile at the North West Hutton (NWH) oil platform. Data on the drilling fluids and chemical products used over the platform's drilling history were transferred from archived well reports into a custom database, to which were added toxicological and safety data. Although the database contained many gaps, it established that only seven chemical products used at NWH were not in the lowest category of the Offshore Chemicals Notification Scheme, and were used in only small quantities. The study therefore supports the view that the main environmental risk posed by cuttings piles comes from hydrocarbon contamination. The (dated) well records could help future core sampling to be targeted at specific locations in the cuttings piles. Data from many platforms could also be pooled to determine generic 'discharge profiles.' Future study would benefit from the existence, in the public domain, of a standardised, 'legacy' database of chemical products.

  6. 77 FR 69797 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in Port Townsend...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-21

    ... transfer span, lift towers, tower foundations, and a portion of the bridge seat and replace them with a new transfer span, bridge seat, and lift cylinder shafts. During the project, up to 56 piles will be removed... are moveable traffic bridges that connect ferries with the terminal dock, allowing the transfer...

  7. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    NASA Astrophysics Data System (ADS)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  8. A new method of testing pile using dynamic P-S-curve made by amplitude of wave train

    NASA Astrophysics Data System (ADS)

    Hu, Yi-Li; Xu, Jun; Duan, Yong-Kong; Xu, Zhao-Yong; Yang, Run-Hai; Zhao, Jin-Ming

    2004-11-01

    A new method of detecting the vertical bearing capacity for single-pile with high strain is discussed in this paper. A heavy hammer or a small type of rocket is used to strike the pile top and the detectors are used to record vibration graphs. An expression of higher degree of strain (deformation force) is introduced. It is testified theoretically that the displacement, velocity and acceleration cannot be obtained by simple integral acceleration and differential velocity when long displacement and high strain exist, namely when the pile phase generates a whole slip relative to the soil body. That is to say that there are non-linear relations between them. It is educed accordingly that the force P and displacement S are calculated from the amplitude of wave train and (dynamic) P-S curve is drew so as to determine the yield points. Further, a method of determining the vertical bearing capacity for single-pile is discussed. A static load test is utilized to check the result of dynamic test and determine the correlative constants of dynamic-static P( Q)- S curve.

  9. A database of archived drilling records of the drill cuttings piles at the North West Hutton oil platform.

    PubMed

    Marsh, Roy

    2003-05-01

    Drill cuttings piles are found underneath several hundred oil platforms in the North Sea, and are contaminated with hydrocarbons and chemical products. This study characterised the environmental risk posed by the cuttings pile at the North West Hutton (NWH) oil platform. Data on the drilling fluids and chemical products used over the platform's drilling history were transferred from archived well reports into a custom database, to which were added toxicological and safety data. Although the database contained many gaps, it established that only seven chemical products used at NWH were not in the lowest category of the Offshore Chemicals Notification Scheme, and were used in only small quantities. The study therefore supports the view that the main environmental risk posed by cuttings piles comes from hydrocarbon contamination. The (dated) well records could help future core sampling to be targeted at specific locations in the cuttings piles. Data from many platforms could also be pooled to determine generic 'discharge profiles.' Future study would benefit from the existence, in the public domain, of a standardised, 'legacy' database of chemical products. PMID:12735956

  10. Nature and origin of the sedimentary pile subducting in the Nankai Through

    NASA Astrophysics Data System (ADS)

    Chauvel, C.; Garcon, M.; Yobregat, E.; Chipoulet, C.; Labanieh, S.

    2013-12-01

    Nd-Hf isotopes and trace and major element concentrations were measured on bulk sediments recovered at Site C0012 during IODP Expedition 322 and 333 in the Shikoku basin. We analyzed the composition of different lithologies such as clay, claystone, sand, sandstone, and ash layers, all through the sedimentary pile, from the surface to the sediment-basalt interface, in order to identify compositional trends and source variations with depth. Major and trace element contents of the background sediments (hemipelagic mudstone) are very homogenous and span a relatively small range of values throughout the entire sedimentary pile. Their composition resembles that of the average upper continental crust of Rudnick and Gao (2003, Treatise on Geochemistry, Vol.3, p. 1-64). Nd and Hf isotopes are more variable, relatively unradiogenic (-8 < ɛNd < -3 ; -4 < ɛHf < +5) but display no systematic variations with depth (Fig. 1). Such isotopic compositions indicate that the background sedimentation of the Shikoku basin may consist of volcaniclastic material from the Izu-Bonin and/or Ryukyu arcs, detrital material eroded from SW Japan and relatively high amount of an evolved continental-derived component, probably Chinese loess as already suggested by Mahomet (2005, Sediment. Geol., 182, p.183-199). Compared to the background sedimentation, volcanic ash layers and volcaniclastic sandstones have very different trace element patterns and more radiogenic Nd-Hf isotopic signature (Fig. 1). Our results allow us to distinguish at least two different volcanic sources for these deposits. At the bottom of the sedimentary pile, siliciclastic sandstones with a mid-Miocene age are present; they have remarkably low ɛNd and ɛHf values (i.e. ɛNd < -8 and ɛHf < -5). Such isotopic compositions clearly demonstrate that their source cannot be the Japanese mainland, as suggested by previous studies (e.g. Underwood et al, 2009, Exp.322 PR ; Fergusson, 2003, Proc. ODP, Sci. Results 190/196). These

  11. Geophysical delineation of acidity and salinity in the Central Manitoba gold mine tailings pile, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Tycholiz, C.; Ferguson, I. J.; Sherriff, B. L.; Cordeiro, M.; Sri Ranjan, R.; Pérez-Flores, M. A.

    2016-08-01

    Surface electrical and electromagnetic geophysical methods can map enhanced electrical conductivity caused by acid mine drainage in mine tailings piles. In this case study, we investigate quantitative relationships between geophysical responses and the electrical conductivity, acidity and salinity of tailing samples at the Central Manitoba Mine tailings in Manitoba, Canada. Previous electromagnetic surveys at the site identified zones of enhanced conductivity that were hypothesized to be caused by acid mine drainage. In the present study, high-resolution EM31 and DC-resistivity measurements were made on a profile through a zone of enhanced conductivity and laboratory measurements of salinity and pH were made on saturation paste extracts from an array of tailing samples collected from the upper 2 m of tailings along the profile. Observed spatial correlation of pH and pore-fluid salinity in the tailings samples confirms that the enhanced conductivity in the Central Manitoba Mine tailings is due to acid mine drainage. Contoured cross-sections of the data indicate that the acid mine drainage is concentrated near the base of the oxidized zone in the thicker parts of the tailings pile. The zone of increased acidity extends to the surface on sloping margins causing an increase in apparent conductivity in shallow penetrating geophysical responses. The quantitative relationship between measured pH and salinity shows that the conductivity increase associated with the acid mine drainage is due only in part to conduction by ions produced from dissociation of sulfuric acid. Comparison of the observations with fluid conductivity estimates based on statistical relationships of pH and ion concentrations in water samples from across the tailings pile shows that Ca2 + and Mg2 + ions also make significant contributions to the conductivity at all values of pH and Cu2 +, Al3 + and Fe3 + ions make additional contributions at low pH. Variability in the measured conductivity at constant

  12. Using binary asteroids to explore the interior geophysics of rubble-pile asteroids

    NASA Astrophysics Data System (ADS)

    Scheeres, D.; Jacobson, S.; McMahon, J.; Hirabayashi, M.

    2014-07-01

    The internal geophysics of small rubble-pile asteroids are largely unexplored, with standard geophysical theories of strength and dissipation not being well matched to the extreme environment these bodies exist in. Interior pressures within rapidly spinning rubble piles are computed to be as small as a few Pascals, a regime in which small non-gravitational forces not considered for larger bodies may become important. The limited research done on the geophysics of such bodies has suggested that the standard geophysical models for internal energy dissipation in this regime require significant modification [1], changing some of the fundamental relations between size and strength. Binary asteroid systems provide a unique opportunity for developing constraints and deeper understanding of the magnitude and operation of tidal dissipation within rubble-pile bodies. Recently, Jacobson and Scheeres [2] proposed that the most common class of binary asteroid systems, those with a synchronized secondary and rapidly spinning primary, may be in an equilibrium state where contractive Binary YORP forces balance against expansive tidal torques due to tidal distortion of the primary body. In such systems it becomes possible to develop estimates of the ratio of tidal dissipation number over tidal Love number, Q/k. The predicted equilibrium semi-major axes for such binary asteroid systems (based on presumed values for the Binary YORP force and Q/k values) has been seen to be consistent with the observed sizes of many of these systems (see figure). To refine the estimates for this ratio it is necessary to both confirm the existence of binary asteroids in such an equilibrium state and develop a better understanding of what value the Binary YORP coefficient of binary systems will have [3]. Recently, it has been verified that the spacecraft-accessible binary asteroid 1996 FG_3 is in such an equilibrium state [4]. The combined detection of such an equilibrium coupled with knowledge about

  13. Trace element emissions from spontaneous combustion of gob piles in coal mines, Shanxi, China

    USGS Publications Warehouse

    Zhao, Y.; Zhang, Jiahua; Chou, C.-L.; Li, Y.; Wang, Z.; Ge, Y.; Zheng, C.

    2008-01-01

    The emissions of potentially hazardous trace elements from spontaneous combustion of gob piles from coal mining in Shanxi Province, China, have been studied. More than ninety samples of solid waste from gob piles in Shanxi were collected and the contents of twenty potentially hazardous trace elements (Be, F, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sn, Sb, Hg, Tl, Pb, Th, and U) in these samples were determined. Trace element contents in solid waste samples showed wide ranges. As compared with the upper continental crust, the solid waste samples are significantly enriched in Se (20x) and Tl (12x) and are moderately enriched in F, As, Mo, Sn, Sb, Hg, Th, and U (2-5x). The solid waste samples are depleted in V, Cr, Mn, Co, Ni, Cu, and Zn. The solid waste samples are enriched in F, V, Mn, Cr, Co, Ni, Cu, Zn, Sb, Th, and U as compared with the Shanxi coals. Most trace elements are higher in the clinker than in the unburnt solid waste except F, Sn, and Hg. Trace element abundances are related to the ash content and composition of the samples. The content of F is negatively correlated with the ash content, while Pb is positively correlated with the ash. The concentrations of As, Mn, Zn, and Cd are highly positively correlated with Fe2O3 in the solid waste. The As content increases with increasing sulfur content in the solid waste. The trace element emissions are calculated for mass balance. The emission factors of trace elements during the spontaneous combustion of the gobs are determined and the trace element concentrations in the flue gas from the spontaneous combustion of solid waste are calculated. More than a half of F, Se, Hg and Pb are released to the atmosphere during spontaneous combustion. Some trace element concentrations in flue gas are higher than the national emission standards. Thus, gob piles from coal mining pose a serious environmental problem. ?? 2007 Elsevier B.V. All rights reserved.

  14. Geophysical experiments to image the shallow internal structure and the moisture distribution of a mine waste rock pile

    NASA Astrophysics Data System (ADS)

    Poisson, Jérôme; Chouteau, Michel; Aubertin, Michel; Campos, Daniel

    2009-02-01

    Several field surveys of a waste rock pile were carried out during the summers of 2002 and 2003 using ground-penetrating radar, electromagnetic conductivity and DC resistivity imaging. The waste rock deposit is prone to generate acid mine drainage (AMD) due to the oxidation of sulphidic minerals. One of the most critical factors that lead to the production of AMD is unsaturated water flow and the ensuing moisture distribution in the waste rock. This geophysical characterization study, performed over a 30 m × 30 m test zone, was designed to image the internal structure controlling the water flux at shallow depth. The subsurface was found to consist of three zones for the first 6 m of the pile, mainly based on electrical resistivities: a thin superficial conductive material, an intermediate 2 to 3 m thick highly resistive zone, and a lower, more conductive medium. With the help of hydrogeological tests, chemical analyses and two 2.5 m-deep trenches, it is shown that the two conductive zones are correlated with fine-grained waste rock and the resistive zone correlates with a coarser material. In the two deeper zones, the contact between the two types of waste rock is typically highlighted by a sharp resistive/conductive boundary. An increase of conductance in the relatively thin upper layer towards the edge of the pile appears to be caused by an increase in thickness of the fine-grained material. Additional geophysical surveys carried out on a profile along the flank of the upper bench of the pile show that the main features of the internal structure are sub-parallel to the slope, at least for the first 3 m in depth. The data also show an increase in resistivity from the top to bottom of the slope, in accordance with expected particle segregation, from fine-grained material at the top to coarser material at the bottom. Wide-angle reflection GPR monitoring during large scale infiltration tests seems to indicate preferential flow paths towards the direction of coarser

  15. A new frog species (Microhylidae:Cophixalus) from boulder-pile habitat of Cape Melville, north-east Australia.

    PubMed

    Hoskin, Conrad J

    2013-01-01

    In Australia, microhylid frogs are found almost exclusively in the tropical north-east, but in this region diversity is high. Sixteen species occur in the Wet Tropics region and a further six species are found further north on Cape York Peninsula. Most Australian microhylid species belong to the genus Cophixalus (18 species). The majority of these have highly localized distributions, with two-thirds being found on single mountain ranges. While most Cophixalus are small (10-29 mm snout to vent length) rainforest species, four differ dramatically in morphology and ecology, being large (30-53 mm) species that inhabit isolated areas ofjumbled boulder-pile habitat. Here I describe a new species of Cophixalus from boulder-pile habitat in the Melville Range on Cape Melville, north-east Cape York Peninsula. Cophixalus petrophilus sp. nov. is highly distinct from all congeners in morphology, colour pattern and mating call. This species is restricted to deeply piled granite boulder habitat that is largely devoid of vegetation. As for the other four boulder-pile Cophixalus, C. petrophilus sp. nov. is large and shows other similar morphological adaptations to this unique habitat (e.g., long limbs, large finger discs). However, it is notable in that it is the smallest of the boulder-pile species (26-32 mm) and it has particularly large eyes. I speculate that the latter trait is an adaptation to dimly lit conditions deep within the boulder-field. Cophixalus petrophilus sp. nov. was only found in exposed boulder habitat, whereas the co-occurring boulder species, C. zweifeli, was found using forested areas on and adjacent to the boulder-fields at night. Cape Melville is the only boulder-field with two co-occurring boulder Cophixalus and it appears that there is habitat partitioning between them. Cophixalus petrophilus sp. nov. has a highly localised distribution but appears common within this and is probably secure.

  16. Late Neolithic vegetation history at the pile-dwelling site of Palù di Livenza (northeastern Italy

    NASA Astrophysics Data System (ADS)

    Pini, Roberta

    2004-12-01

    The Late Neolithic pile-dwelling of Palù di Livenza yielded archaeological remains typical of the Square Mouth Pottery and Lagozza Cultures. A palynological investigation reveals important changes in the vegetation due to anthropogenic pressure. Between ca. 6590 and 5960 cal. yr BP, dense oak wood forests with deciduous Quercus, Fagus and Corylus extended around the mire, with no signs of human impact. The establishment of the pile-dwelling, dated to ca. 5960 cal. yr BP, led to a strong reduction of forests, reclamation of wetlands, and expansion of herbaceous communities, with cultivated species, infestant weeds, nitrophilous and ruderal herbs, pastures and meadows. According to AMS dates and previous archaeological chronologies, the pile-dwelling persisted for about 700 years (from ca. 5960 to 5260 cal. yr BP). The history of the pile-dwelling after ca. 5260 cal. yr BP cannot be reconstructed because of recent contamination of the top part of the section. Rarefaction analysis was applied to estimate changes of palynological richness through time: the highest E(Tn) (between 56 and 69 taxa) are contemporaneous with the local development of the pile-dwelling. The comparison of pollen data with archaeobotanical evidence indicates that Fragaria vesca, Malus sylvestris, Papaver somniferum and Physalis alkekengi were gathered at some distance from the site and that Linum usitatissimum is strongly under-represented in pollen samples. Crop cultivation can be estimated for a radius of several hundred metres around the mire. Palù di Livenza is significant in the context of Neolithic archaeobotany of northern Italy and neighbouring countries. Copyright

  17. Geochemical characterization of acid mine drainage from a waste rock pile, Mine Doyon, Québec, Canada

    NASA Astrophysics Data System (ADS)

    Sracek, O.; Choquette, M.; Gélinas, P.; Lefebvre, R.; Nicholson, R. V.

    2004-03-01

    Water quality in the unsaturated and saturated zones of a waste rock pile containing sulphides was investigated. The main objectives of the project were (1) the evaluation of geochemical trends including the acid mine drainage (AMD)-buffering mechanism and the role of secondary minerals, and (2) the investigation of the use of stable isotopes for the interpretation of physical and geochemical processes in waste rock. Pore water in unsaturated zone was sampled from suction lysimeters and with piezometers in underlying saturated rocks. The investigation revealed strong temporal (dry period vs. recharge period), and spatial (slope vs. central region of pile) variability in the formation of acid mine drainage. The main secondary minerals observed were gypsum and jarosite. There was a higher concentration of gypsum in solid phase at Site TBT than at Site 6, suggesting that part of the gypsum formed at Site 6 in the early stage of AMD has been already dissolved. Formation of secondary minerals contributed to the formation of AMD by opening of foliation planes in waste rock, thus increasing the access of oxidants like O 2 and Fe 3+ to previously encapsulated pyrite. The behavior of several dissolved species such as Mg, Al, and Fe 2+ can be considered as conservative in the leachate. Stable isotopes, deuterium and 18O, indicated internal evaporation within the pile, and were used to trace recharge pulses from snowmelt. Isotope trends for 34S and 18O(SO 4) indicated a lack of sulfate reduction and zones of active oxidation of pyrite, respectively. Results of numerical modeling of pyrite oxidation and gas and water transport were consistent with geochemical and isotopic trends and confirmed zones of high evaporation rate within the rock pile close to the slope. The results indicate that physical and chemical processes within the pile are strongly coupled and cannot be considered separately when oxidation rates are high and influence gas transport as a result of heat

  18. Geochemical characterization of acid mine drainage from a waste rock pile, Mine Doyon, Québec, Canada.

    PubMed

    Sracek, O; Choquette, M; Gélinas, P; Lefebvre, R; Nicholson, R V

    2004-03-01

    Water quality in the unsaturated and saturated zones of a waste rock pile containing sulphides was investigated. The main objectives of the project were (1) the evaluation of geochemical trends including the acid mine drainage (AMD)-buffering mechanism and the role of secondary minerals, and (2) the investigation of the use of stable isotopes for the interpretation of physical and geochemical processes in waste rock. Pore water in unsaturated zone was sampled from suction lysimeters and with piezometers in underlying saturated rocks. The investigation revealed strong temporal (dry period vs. recharge period), and spatial (slope vs. central region of pile) variability in the formation of acid mine drainage. The main secondary minerals observed were gypsum and jarosite. There was a higher concentration of gypsum in solid phase at Site TBT than at Site 6, suggesting that part of the gypsum formed at Site 6 in the early stage of AMD has been already dissolved. Formation of secondary minerals contributed to the formation of AMD by opening of foliation planes in waste rock, thus increasing the access of oxidants like O2 and Fe3+ to previously encapsulated pyrite. The behavior of several dissolved species such as Mg, Al, and Fe2+ can be considered as conservative in the leachate. Stable isotopes, deuterium and 18O, indicated internal evaporation within the pile, and were used to trace recharge pulses from snowmelt. Isotope trends for 34S and 18O(SO4) indicated a lack of sulfate reduction and zones of active oxidation of pyrite, respectively. Results of numerical modeling of pyrite oxidation and gas and water transport were consistent with geochemical and isotopic trends and confirmed zones of high evaporation rate within the rock pile close to the slope. The results indicate that physical and chemical processes within the pile are strongly coupled and cannot be considered separately when oxidation rates are high and influence gas transport as a result of heat generation

  19. Improvement of the performance of a large diameter silicon solar cell. Final report. Amelioration des performances de la pile solaire au silicium de grand diametre. Rapport final

    SciTech Connect

    Diguet, D.

    1984-01-01

    A method of preparing large diameter solar cells has been developed to a stage where reproducible performances are obtained. While all the problems concerned with the intrinsic quality of the silicon used in the solar cells have not yet been solved, analytical methods have been developed for selecting the most suitable silicon samples prior to use. Studies concerned with the preparation of the substrate, deposition of the antireflection bed, and soldering of the connections are reported. Equipment for examining the solar cells is described.

  20. Prediction of the initial normal stress in piles and anchors constructed using expansive cements

    NASA Astrophysics Data System (ADS)

    Haberfield, C. M.

    2000-03-01

    Uses for expansive cements and additives have extended well beyond off-setting the shrinkage characteristics of grout and concrete to include enhancement of rock anchor and pile performance, providing an alternative form of connection for tubular members in off-shore structures and as an excavation tool in open-pit mines. In each case, the design rules governing the quantity of expansive additive to be used are based on guesswork or empiricism. This paper presents analytical solutions for estimating the degree of expansion and the level of normal stress developed for a range of different boundary conditions and expansive additive contents. The expansion process is modelled as a thermal expansion and is governed by one parameter that depends on the type of expansive additive and its dosage. Simple laboratory procedures for determining this property are outlined. Predictions from the analytical solutions are compared with laboratory experiments.