Effect of bicycle saddle designs on the pressure to the perineum of the bicyclist.

Science.gov (United States)

Lowe, Brian D; Schrader, Steven M; Breitenstein, Michael J

2004-06-01

Increasing awareness of an association between bicycling and male sexual dysfunction has led to the appearance of a variety of bicycle saddles that share the design objective of reducing pressure in the groin of the cyclist by removal of the narrow protruding nose of the saddle. This study compared three of these saddle designs to a traditional sport/road racing saddle with a narrow protruding nose in terms of pressure in the region of the perineum (groin) of the cyclist. Saddle, pedal, and handlebar contact pressure were measured from 33 bicycle police patrol officers pedaling a stationary bicycle at a controlled cadence and workload. Pressure was characterized over the saddle as a whole and over a region of the saddle assumed to represent pressure on the cyclist's perineum located anteriorly to the ischial tuberosities. The traditional sport/racing saddle was associated with more than two times the pressure in the perineal region than the saddles without a protruding nose (P perineum of the bicyclist.

Complex saddle points in QCD at finite temperature and density

Science.gov (United States)

Nishimura, Hiromichi; Ogilvie, Michael C.; Pangeni, Kamal

2014-08-01

The sign problem in QCD at finite temperature and density leads naturally to the consideration of complex saddle points of the action or effective action. The global symmetry CK of the finite-density action, where C is charge conjugation and K is complex conjugation, constrains the eigenvalues of the Polyakov loop operator P at a saddle point in such a way that the action is real at a saddle point, and net color charge is zero. The values of TrFP and TrFP† at the saddle point are real but not identical, indicating the different free energy cost associated with inserting a heavy quark versus an antiquark into the system. At such complex saddle points, the mass matrix associated with Polyakov loops may have complex eigenvalues, reflecting oscillatory behavior in color-charge densities. We illustrate these properties with a simple model which includes the one-loop contribution of gluons and two flavors of massless quarks moving in a constant Polyakov loop background. Confinement-deconfinement effects are modeled phenomenologically via an added potential term depending on the Polyakov loop eigenvalues. For sufficiently large temperature T and quark chemical potential μ, the results obtained reduce to those of perturbation theory at the complex saddle point. These results may be experimentally relevant for the compressed baryonic matter experiment at FAIR.

Regularization of the Boundary-Saddle-Node Bifurcation

Directory of Open Access Journals (Sweden)

Xia Liu

2018-01-01

Full Text Available In this paper we treat a particular class of planar Filippov systems which consist of two smooth systems that are separated by a discontinuity boundary. In such systems one vector field undergoes a saddle-node bifurcation while the other vector field is transversal to the boundary. The boundary-saddle-node (BSN bifurcation occurs at a critical value when the saddle-node point is located on the discontinuity boundary. We derive a local topological normal form for the BSN bifurcation and study its local dynamics by applying the classical Filippov’s convex method and a novel regularization approach. In fact, by the regularization approach a given Filippov system is approximated by a piecewise-smooth continuous system. Moreover, the regularization process produces a singular perturbation problem where the original discontinuous set becomes a center manifold. Thus, the regularization enables us to make use of the established theories for continuous systems and slow-fast systems to study the local behavior around the BSN bifurcation.

Time delays across saddles as a test of modified gravity

International Nuclear Information System (INIS)

Magueijo, João; Mozaffari, Ali

2013-01-01

Modified gravity theories can produce strong signals in the vicinity of the saddles of the total gravitational potential. In a sub-class of these models, this translates into diverging time delays for echoes crossing the saddles. Such models arise from the possibility that gravity might be infrared divergent or confined, and if suitably designed they are very difficult to rule out. We show that Lunar Laser Ranging during an eclipse could probe the time-delay effect within metres of the saddle, thereby proving or excluding these models. Very Large Baseline Interferometry, instead, could target delays across the Jupiter–Sun saddle. Such experiments would shed light on the infrared behaviour of gravity and examine the puzzling possibility that there might be well-hidden regions of strong gravity and even singularities inside the solar system. (fast track communication)

Electrons at the monkey saddle: A multicritical Lifshitz point

Science.gov (United States)

Shtyk, A.; Goldstein, G.; Chamon, C.

2017-01-01

We consider two-dimensional interacting electrons at a monkey saddle with dispersion ∝px3-3 pxpy2 . Such a dispersion naturally arises at the multicritical Lifshitz point when three Van Hove saddles merge in an elliptical umbilic elementary catastrophe, which we show can be realized in biased bilayer graphene. A multicritical Lifshitz point of this kind can be identified by its signature Landau level behavior Em∝(Bm ) 3 /2 and related oscillations in thermodynamic and transport properties, such as de Haas-Van Alphen and Shubnikov-de Haas oscillations, whose period triples as the system crosses the singularity. We show, in the case of a single monkey saddle, that the noninteracting electron fixed point is unstable to interactions under the renormalization-group flow, developing either a superconducting instability or non-Fermi-liquid features. Biased bilayer graphene, where there are two non-nested monkey saddles at the K and K' points, exhibits an interplay of competing many-body instabilities, namely, s -wave superconductivity, ferromagnetism, and spin- and charge-density waves.

Assessment of saddle-point-mass predictions for astrophysical applications

Energy Technology Data Exchange (ETDEWEB)

Kelic, A.; Schmidt, K.H.

2005-07-01

Using available experimental data on fission barriers and ground-state masses, a detailed study on the predictions of different models concerning the isospin dependence of saddle-point masses is performed. Evidence is found that several macroscopic models yield unrealistic saddle-point masses for very neutron-rich nuclei, which are relevant for the r-process nucleosynthesis. (orig.)

Divided Saddle Theory: A New Idea for Rate Constant Calculation.

Science.gov (United States)

Daru, János; Stirling, András

2014-03-11

We present a theory of rare events and derive an algorithm to obtain rates from postprocessing the numerical data of a free energy calculation and the corresponding committor analysis. The formalism is based on the division of the saddle region of the free energy profile of the rare event into two adjacent segments called saddle domains. The method is built on sampling the dynamics within these regions: auxiliary rate constants are defined for the saddle domains and the absolute forward and backward rates are obtained by proper reweighting. We call our approach divided saddle theory (DST). An important advantage of our approach is that it requires only standard computational techniques which are available in most molecular dynamics codes. We demonstrate the potential of DST numerically on two examples: rearrangement of alanine-dipeptide (CH3CO-Ala-NHCH3) conformers and the intramolecular Cope reaction of the fluxional barbaralane molecule.

GEODESIC RECONSTRUCTION, SADDLE ZONES & HIERARCHICAL SEGMENTATION

Directory of Open Access Journals (Sweden)

Serge Beucher

2011-05-01

Full Text Available The morphological reconstruction based on geodesic operators, is a powerful tool in mathematical morphology. The general definition of this reconstruction supposes the use of a marker function f which is not necessarily related to the function g to be built. However, this paper deals with operations where the marker function is defined from given characteristic regions of the initial function f, as it is the case, for instance, for the extrema (maxima or minima but also for the saddle zones. Firstly, we show that the intuitive definition of a saddle zone is not easy to handle, especially when digitised images are involved. However, some of these saddle zones (regional ones also called overflow zones can be defined, this definition providing a simple algorithm to extract them. The second part of the paper is devoted to the use of these overflow zones as markers in image reconstruction. This reconstruction provides a new function which exhibits a new hierarchy of extrema. This hierarchy is equivalent to the hierarchy produced by the so-called waterfall algorithm. We explain why the waterfall algorithm can be achieved by performing a watershed transform of the function reconstructed by its initial watershed lines. Finally, some examples of use of this hierarchical segmentation are described.

The Sun-Earth saddle point: characterization and opportunities to test general relativity

Science.gov (United States)

Topputo, Francesco; Dei Tos, Diogene A.; Rasotto, Mirco; Nakamiya, Masaki

2018-04-01

The saddle points are locations where the net gravitational accelerations balance. These regions are gathering more attention within the astrophysics community. Regions about the saddle points present clean, close-to-zero background acceleration environments where possible deviations from General Relativity can be tested and quantified. Their location suggests that flying through a saddle point can be accomplished by leveraging highly nonlinear orbits. In this paper, the geometrical and dynamical properties of the Sun-Earth saddle point are characterized. A systematic approach is devised to find ballistic orbits that experience one or multiple passages through this point. A parametric analysis is performed to consider spacecraft initially on L_{1,2} Lagrange point orbits. Sun-Earth saddle point ballistic fly-through trajectories are evaluated and classified for potential use. Results indicate an abundance of short-duration, regular solutions with a variety of characteristics.

Developments of saddle field ion sources and their applications

International Nuclear Information System (INIS)

Abdelrahman, M.M.; Helal, A.G.

2009-01-01

Ion sources should have different performance parameters according to the various applications for which they are used, ranging from ion beam production to high energy ion implanters. There are many kinds of ion sources, which produce different ion beams with different characteristics. This paper deals with the developments and applications of some saddle field ion sources which were designed and constructed in our lab. Theory of operation and types of saddle field ion sources are discussed in details. Some experimental results are given. The saddle field ion sources operate at low gas pressure and require neither magnetic field nor filament. This type of ion sources is used for many different applications as ion beam machining, sputtering, cleaning and profiling for surface analysis etc

19 CFR 148.32 - Vehicles, aircraft, boats, teams and saddle horses taken abroad.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 2 2010-04-01 2010-04-01 false Vehicles, aircraft, boats, teams and saddle horses... for Returning Residents § 148.32 Vehicles, aircraft, boats, teams and saddle horses taken abroad. (a) Admission free of duty. Automobiles and other vehicles, aircraft, boats, teams and saddle horses, together...

Maximal saddle solution of a nonlinear elliptic equation involving the ...

Indian Academy of Sciences (India)

College of Mathematics and Econometrics, Hunan University, Changsha 410082, China. E-mail: huahuiyan@163.com; duzr@hnu.edu.cn. MS received 3 September 2012; revised 20 December 2012. Abstract. A saddle solution is called maximal saddle solution if its absolute value is not smaller than those absolute values ...

Evaluation of saddle and driving aptitudes in Monterufoli pony

Directory of Open Access Journals (Sweden)

Riccardo Bozzi

2010-01-01

Full Text Available The Monterufoli pony is an endangered Tuscan breed. In the 80’s began a project for the conservation of the breed and at present there are roughly 200 individuals. The equine was once utilized for saddle and driving and this study deals with the training for these two aptitudes. The mor- phologic type of the pony seems suited for saddle, in particular for children and beginners, and driving. The ponies showed developed chest, strong legs with short shanks: all these characters were useful for trot and driving. In this trial 3-4 years old never tamed Monterufoli ponies were opportunely choose and subsequently trained for saddle and driving. The ponies were submitted to the “aptitude test” for the two aptitudes and the results were good both for practical and character sides. The marks for sad- dle and driving were 8.16 and 8.06 respectively. Also the 3 ponies showed good results for the Aptitude Index: 7.60, 7.87 and 7.89. The results of the trial showed the excellent ability of the Monterufoli pony for saddle and driving. The good results of the test are important for the diffusion of the breed in the territory and in particular in horse centres and in equestrian tourism sites.

Chaotic saddles in nonlinear modulational interactions in a plasma

International Nuclear Information System (INIS)

Miranda, Rodrigo A.; Rempel, Erico L.; Chian, Abraham C.-L.

2012-01-01

A nonlinear model of modulational processes in the subsonic regime involving a linearly unstable wave and two linearly damped waves with different damping rates in a plasma is studied numerically. We compute the maximum Lyapunov exponent as a function of the damping rates in a two-parameter space, and identify shrimp-shaped self-similar structures in the parameter space. By varying the damping rate of the low-frequency wave, we construct bifurcation diagrams and focus on a saddle-node bifurcation and an interior crisis associated with a periodic window. We detect chaotic saddles and their stable and unstable manifolds, and demonstrate how the connection between two chaotic saddles via coupling unstable periodic orbits can result in a crisis-induced intermittency. The relevance of this work for the understanding of modulational processes observed in plasmas and fluids is discussed.

Chaotic saddles in nonlinear modulational interactions in a plasma

Energy Technology Data Exchange (ETDEWEB)

Miranda, Rodrigo A. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); University of Brasilia (UnB), Gama Campus, and Plasma Physics Laboratory, Institute of Physics, Brasilia, DF 70910-900 (Brazil); Rempel, Erico L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); Chian, Abraham C.-L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); Observatoire de Paris, LESIA, CNRS, 92195 Meudon (France)

2012-11-15

A nonlinear model of modulational processes in the subsonic regime involving a linearly unstable wave and two linearly damped waves with different damping rates in a plasma is studied numerically. We compute the maximum Lyapunov exponent as a function of the damping rates in a two-parameter space, and identify shrimp-shaped self-similar structures in the parameter space. By varying the damping rate of the low-frequency wave, we construct bifurcation diagrams and focus on a saddle-node bifurcation and an interior crisis associated with a periodic window. We detect chaotic saddles and their stable and unstable manifolds, and demonstrate how the connection between two chaotic saddles via coupling unstable periodic orbits can result in a crisis-induced intermittency. The relevance of this work for the understanding of modulational processes observed in plasmas and fluids is discussed.

Featured Partner: Saddle Creek Logistics Services

Science.gov (United States)

This EPA fact sheet spotlights Saddle Creek Logistics as a SmartWay partner committed to sustainability in reducing greenhouse gas emissions and air pollution caused by freight transportation, partly by growing its compressed natural gas (CNG) vehicles for

Measuring the distance from saddle points and driving to locate them over quantum control landscapes

International Nuclear Information System (INIS)

Sun, Qiuyang; Riviello, Gregory; Rabitz, Herschel; Wu, Re-Bing

2015-01-01

Optimal control of quantum phenomena involves the introduction of a cost functional J to characterize the degree of achieving a physical objective by a chosen shaped electromagnetic field. The cost functional dependence upon the control forms a control landscape. Two theoretically important canonical cases are the landscapes associated with seeking to achieve either a physical observable or a unitary transformation. Upon satisfaction of particular assumptions, both landscapes are analytically known to be trap-free, yet possess saddle points at precise suboptimal J values. The presence of saddles on the landscapes can influence the effort needed to find an optimal field. As a foundation to future algorithm development and analyzes, we define metrics that identify the ‘distance’ from a given saddle based on the sufficient and necessary conditions for the existence of the saddles. Algorithms are introduced utilizing the metrics to find a control such that the dynamics arrive at a targeted saddle. The saddle distance metric and saddle-seeking methodology is tested numerically in several model systems. (paper)

Natural Preconditioning and Iterative Methods for Saddle Point Systems

KAUST Repository

Pestana, Jennifer

2015-01-01

© 2015 Society for Industrial and Applied Mathematics. The solution of quadratic or locally quadratic extremum problems subject to linear(ized) constraints gives rise to linear systems in saddle point form. This is true whether in the continuous or the discrete setting, so saddle point systems arising from the discretization of partial differential equation problems, such as those describing electromagnetic problems or incompressible flow, lead to equations with this structure, as do, for example, interior point methods and the sequential quadratic programming approach to nonlinear optimization. This survey concerns iterative solution methods for these problems and, in particular, shows how the problem formulation leads to natural preconditioners which guarantee a fast rate of convergence of the relevant iterative methods. These preconditioners are related to the original extremum problem and their effectiveness - in terms of rapidity of convergence - is established here via a proof of general bounds on the eigenvalues of the preconditioned saddle point matrix on which iteration convergence depends.

Basic kinematics of the saddle and rider in high-level dressage horses trotting on a treadmill.

Science.gov (United States)

Byström, A; Rhodin, M; von Peinen, K; Weishaupt, M A; Roepstorff, L

2009-03-01

A comprehensive kinematic description of rider and saddle movements is not yet present in the scientific literature. To describe saddle and rider movements in a group of high-level dressage horses and riders. Seven high-level dressage horses and riders were subjected to kinematic measurements while performing collected trot on a treadmill. For analysis a rigid body model for the saddle and core rider segments, projection angles of the rider's extremities and the neck and trunk of the horse, and distances between markers selected to indicate rider position were used. For a majority of the variables measured it was possible to describe a common pattern for the group. Rotations around the transverse axis (pitch) were generally biphasic for each diagonal. During the first half of stance the saddle rotated anti-clockwise and the rider's pelvis clockwise viewed from the right and the rider's lumbar back extended. During the later part of stance and the suspension phase reverse pitch rotations were observed. Rotations of the saddle and core rider segments around the longitudinal (roll) and vertical axes (yaw) changed direction only around time of contact of each diagonal. The saddles and riders of high-level dressage horses follow a common movement pattern at collected trot. The movements of the saddle and rider are clearly related to the movements of the horse and saddle movements also seem to be influenced by the rider. Knowledge about rider and saddle movements can further our understanding of, and hence possibilities to prevent, orthopaedic injuries related to the exposure of the horse to a rider and saddle.

The Antitriangular Factorization of Saddle Point Matrices

KAUST Repository

Pestana, J.; Wathen, A. J.

2014-01-01

Mastronardi and Van Dooren [SIAM J. Matrix Anal. Appl., 34 (2013), pp. 173-196] recently introduced the block antitriangular ("Batman") decomposition for symmetric indefinite matrices. Here we show the simplification of this factorization for saddle

Codimension n saddle-nodes

International Nuclear Information System (INIS)

Gheiner, Jaques

2014-01-01

We consider the generic unfolding of a diffeomorphism on a compact C ∞ manifold that is Morse–Smale except for one non-hyperbolic periodic orbit being a codimension n saddle-node (one eigenvalue is 1, the other eigenvalues have norm different from 1). Local and global bifurcations are described. We characterize structural stability of the unfolding, depending on the codimension. A universal model of the unfolding is given when there is stability. Dynamical behaviour is analysed in other cases. (paper)

Reconstruction of chaotic saddles by classification of unstable periodic orbits: Kuramoto-Sivashinsky equation

Energy Technology Data Exchange (ETDEWEB)

Saiki, Yoshitaka, E-mail: yoshi.saiki@r.hit-u.ac.jp [Graduate School of Commerce and Management, Hitotsubashi University, Tokyo 186-8601 (Japan); Yamada, Michio [Research Institute for Mathematical Sciences (RIMS), Kyoto University, Kyoto 606-8502 (Japan); Chian, Abraham C.-L. [Paris Observatory, LESIA, CNRS, 92195 Meudon (France); National Institute for Space Research (INPE), P.O. Box 515, São José dos Campos, São Paulo 12227-010 (Brazil); Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil); School of Mathematical Sciences, University of Adelaide, Adelaide SA 5005 (Australia); Department of Biomedical Engineering, George Washington University, Washington, DC 20052 (United States); Miranda, Rodrigo A. [Faculty UnB-Gama, and Plasma Physics Laboratory, Institute of Physics, University of Brasília (UnB), Brasília DF 70910-900 (Brazil); Rempel, Erico L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil)

2015-10-15

The unstable periodic orbits (UPOs) embedded in a chaotic attractor after an attractor merging crisis (MC) are classified into three subsets, and employed to reconstruct chaotic saddles in the Kuramoto-Sivashinsky equation. It is shown that in the post-MC regime, the two chaotic saddles evolved from the two coexisting chaotic attractors before crisis can be reconstructed from the UPOs embedded in the pre-MC chaotic attractors. The reconstruction also involves the detection of the mediating UPO responsible for the crisis, and the UPOs created after crisis that fill the gap regions of the chaotic saddles. We show that the gap UPOs originate from saddle-node, period-doubling, and pitchfork bifurcations inside the periodic windows in the post-MC chaotic region of the bifurcation diagram. The chaotic attractor in the post-MC regime is found to be the closure of gap UPOs.

Reconstruction of chaotic saddles by classification of unstable periodic orbits: Kuramoto-Sivashinsky equation

International Nuclear Information System (INIS)

Saiki, Yoshitaka; Yamada, Michio; Chian, Abraham C.-L.; Miranda, Rodrigo A.; Rempel, Erico L.

2015-01-01

The unstable periodic orbits (UPOs) embedded in a chaotic attractor after an attractor merging crisis (MC) are classified into three subsets, and employed to reconstruct chaotic saddles in the Kuramoto-Sivashinsky equation. It is shown that in the post-MC regime, the two chaotic saddles evolved from the two coexisting chaotic attractors before crisis can be reconstructed from the UPOs embedded in the pre-MC chaotic attractors. The reconstruction also involves the detection of the mediating UPO responsible for the crisis, and the UPOs created after crisis that fill the gap regions of the chaotic saddles. We show that the gap UPOs originate from saddle-node, period-doubling, and pitchfork bifurcations inside the periodic windows in the post-MC chaotic region of the bifurcation diagram. The chaotic attractor in the post-MC regime is found to be the closure of gap UPOs

Preconditioners for regularized saddle point matrices

Czech Academy of Sciences Publication Activity Database

Axelsson, Owe

2011-01-01

Roč. 19, č. 2 (2011), s. 91-112 ISSN 1570-2820 Institutional research plan: CEZ:AV0Z30860518 Keywords : saddle point matrices * preconditioning * regularization * eigenvalue clustering Subject RIV: BA - General Mathematics Impact factor: 0.533, year: 2011 http://www.degruyter.com/view/j/jnma.2011.19.issue-2/jnum.2011.005/jnum.2011.005. xml

Influence of girth strap placement and panel flocking material on the saddle pressure pattern during riding of horses.

Science.gov (United States)

Byström, A; Stalfelt, A; Egenvall, A; Von Peinen, K; Morgan, K; Roepstorff, L

2010-11-01

Saddle fit is well recognised as an important factor for the health and performance of riding horses. However, only few studies have addressed general effects of different saddle construction details within a group of horses. To assess the influence of girth strap placement, traditional vs. v-system, and panel flocking material, wool vs. synthetic foam, on the saddle pressure pattern during riding. Six horses were ridden by 3 riders in sitting and rising trot and sitting canter. Saddle pressure was measured with 3 different saddle variants: 1) wool flocked panels and traditional girthing (baseline); 2) wool flocked panels and v-system girthing; and 3) foam filled panels and traditional girthing. From the pressure data, a number of descriptive variables were extracted. These were analysed using ANCOVA models with horse, rider, saddle, seat (sitting/rising, trot only) and speed as independent variables. With foam filled panels stride maximum pressures under the hind part of the saddle increased by 7-12% and the area under the saddle with a stride mean pressure >11 kPa increased by 114 cm(2) in trot and 127 cm(2) in canter. With v-system girthing, the latter variable also increased, but only by 53 and 38 cm(2) in trot and canter, respectively. In addition, stride maximum pressures under the front part of the saddle tended to increase (≤ 9%). Both flocking material and girthing have a significant influence on the saddle pressure and should thus be considered in saddle fitting. Wool seems a better flocking material than foam of the type used in the current study. For girthing, traditional placement seems equally good if not better than the v-system. However, further studies are needed to show if these results are valid for a larger population of riding horses. © 2010 EVJ Ltd.

DETECTING ALIEN LIMIT CYCLES NEAR A HAMILTONIAN 2-SADDLE CYCLE

OpenAIRE

LUCA, Stijn; DUMORTIER, Freddy; Caubergh, M.; Roussarie, R.

2009-01-01

This paper aims at providing and example of a cubic Hamiltonian 2-saddle cycle that after bifurcation can give rise to an alien limit cycle; this is a limit cycle that is not controlled by a zero of the related Abelian integral. To guarantee the existence of an alien limit cycle one can verify generic conditions on the Abelian integral and on the transition map associated to the connections of the 2-saddle cycle. In this paper, a general method is developed to compute the first and second der...

Fission along the mass asymmetry coordinate: an experimental evaluation of the conditional saddle masses and of the Businaro-Gallone point

International Nuclear Information System (INIS)

Moretto, L.G.; McMahan, M.A.; Sobotka, L.G.; Wozniak, G.J.

1984-12-01

The importance of empirically determining the ridge line of conditional saddle points is discussed in view of the recent liquid drop model refinements, like diffuseness and finite range. Two series of experiments are presented. The first series involves the complex fragment emission from compound nuclei resulting from the 3 He + Ag reaction. Kinetic energy distributions and excitation functions are shown, and the conditional barriers are obtained over a range of atomic numbers. In the second series, reverse kinematic reactions like Ge, Nb, La + Be, C are studied. The fragments emitted cover the entire Z range, from Z = 1 to symmetric splitting. Their origin from a full momentum transfer intermediate is shown. From the complete charge distributions it is possible to conclude that the Businaro-Gallone transition is observed. 15 references

Parametric CAD and Fea Model of a Saddle Tapping Tee

DEFF Research Database (Denmark)

A. Kristensen, Anders Schmidt; Lund Jepsen, Kristian

2007-01-01

 Often it is necessary to branch of a pipe section on an oilrig. This operation is often performed by making a so-called "Hot Tapping", which involves welding a pipe and a flange on to the pipe section. A spherical valve and a gate are mounted on to the flange, i.e. weld-o-let. In order to perform...... the welding operations a so-called habitat must be constructed. This habitat encapsulates the "Hot Tapping" spot and is relatively costly. Thus, to avoid weld operations on to the pipeline, a solution with clamps has been developed, i.e. a Saddle Tapping Tee. The Saddle Tapping Tee is clamped on the pipe...... is determined from paragraph K302.3.2 in ASME B31.3. A full parametric 3D CAD model of the Saddle Tapping Tee is developed where a number of user-defined parameters are controlled from an Excel spreadsheet allowing parameter studies and technical documentation to be generated effectively. The same Excel spread...

Paleoseismic evidence for late Holocene tectonic deformation along the Saddle mountain fault zone, Southeastern Olympic Peninsula, Washington

Science.gov (United States)

Barnett, Elizabeth; Sherrod, Brian; Hughes, Jonathan F.; Kelsey, Harvey M.; Czajkowski, Jessica L.; Walsh, Timothy J.; Contreras, Trevor A.; Schermer, Elizabeth R.; Carson, Robert J.

2015-01-01

Trench and wetland coring studies show that northeast‐striking strands of the Saddle Mountain fault zone ruptured the ground about 1000 years ago, generating prominent scarps. Three conspicuous subparallel fault scarps can be traced for 15 km on Light Detection and Ranging (LiDAR) imagery, traversing the foothills of the southeast Olympic Mountains: the Saddle Mountain east fault, the Saddle Mountain west fault, and the newly identified Sund Creek fault. Uplift of the Saddle Mountain east fault scarp impounded stream flow, forming Price Lake and submerging an existing forest, thereby leaving drowned stumps still rooted in place. Stratigraphy mapped in two trenches, one across the Saddle Mountain east fault and the other across the Sund Creek fault, records one and two earthquakes, respectively, as faulting juxtaposed Miocene‐age bedrock against glacial and postglacial deposits. Although the stratigraphy demonstrates that reverse motion generated the scarps, slip indicators measured on fault surfaces suggest a component of left‐lateral slip. From trench exposures, we estimate the postglacial slip rate to be 0.2  mm/yr and between 0.7 and 3.2  mm/yr during the past 3000 years. Integrating radiocarbon data from this study with earlier Saddle Mountain fault studies into an OxCal Bayesian statistical chronology model constrains the most recent paleoearthquake age of rupture across all three Saddle Mountain faults to 1170–970 calibrated years (cal B.P.), which overlaps with the nearby Mw 7.5 1050–1020 cal B.P. Seattle fault earthquake. An earlier earthquake recorded in the Sund Creek trench exposure, dates to around 3500 cal B.P. The geometry of the Saddle Mountain faults and their near‐synchronous rupture to nearby faults 1000 years ago suggest that the Saddle Mountain fault zone forms a western boundary fault along which the fore‐arc blocks migrate northward in response to margin‐parallel shortening across the Puget Lowland.

Model selection in kernel ridge regression

DEFF Research Database (Denmark)

Exterkate, Peter

2013-01-01

Kernel ridge regression is a technique to perform ridge regression with a potentially infinite number of nonlinear transformations of the independent variables as regressors. This method is gaining popularity as a data-rich nonlinear forecasting tool, which is applicable in many different contexts....... The influence of the choice of kernel and the setting of tuning parameters on forecast accuracy is investigated. Several popular kernels are reviewed, including polynomial kernels, the Gaussian kernel, and the Sinc kernel. The latter two kernels are interpreted in terms of their smoothing properties......, and the tuning parameters associated to all these kernels are related to smoothness measures of the prediction function and to the signal-to-noise ratio. Based on these interpretations, guidelines are provided for selecting the tuning parameters from small grids using cross-validation. A Monte Carlo study...

Optimization of saddle coils for magnetic resonance imaging

International Nuclear Information System (INIS)

Salmon, Carlos Ernesto Garrido; Vidoto, Edson Luiz Gea; Martins, Mateus Jose; Tannus, Alberto

2006-01-01

In Nuclear Magnetic Resonance (NMR) experiments, besides the apparatus designed to acquire the NMR signal, it is necessary to generate a radio frequency electromagnetic field using a device capable to transduce electromagnetic power into a transverse magnetic field. We must generate this transverse homogeneous magnetic field inside the region of interest with minimum power consumption. Many configurations have been proposed for this task, from coils to resonators. For low field intensity (<0.5 T) and small sample dimensions (<30 cm), the saddle coil configuration has been widely used. In this work we present a simplified method for calculating the magnetic field distribution in these coils considering the current density profile. We propose an optimized saddle configuration as a function of the dimensions of the region of interest, taking into account the uniformity and the sensitivity. In order to evaluate the magnetic field uniformity three quantities have been analyzed: Non-uniformity, peak-to-peak homogeneity and relative uniformity. Some experimental results are presented to validate our calculation. (author)

Natural Preconditioning and Iterative Methods for Saddle Point Systems

KAUST Repository

Pestana, Jennifer; Wathen, Andrew J.

2015-01-01

or the discrete setting, so saddle point systems arising from the discretization of partial differential equation problems, such as those describing electromagnetic problems or incompressible flow, lead to equations with this structure, as do, for example

Generalized saddle point condition for ignition in a tokamak reactor with temperature and density profiles

International Nuclear Information System (INIS)

Mitari, O.; Hirose, A.; Skarsgard, H.M.

1989-01-01

In this paper, the concept of a generalized ignition contour map, is extended to the realistic case of a plasma with temperature and density profiles in order to study access to ignition in a tokamak reactor. The generalized saddle point is found to lie between the Lawson and ignition conditions. If the height of the operation path with Goldston L-mode scaling is higher than the generalized saddle point, a reactor can reach ignition with this scaling for the case with no confinement degradation effect due to alpha-particle heating. In this sense, the saddle point given in a general form is a new criterion for reaching ignition. Peaking the profiles for the plasma temperature and density can lower the height of the generalized saddle point and help a reactor to reach ignition. With this in mind, the authors can judge whether next-generation tokamaks, such as Compact Ignition Tokamak, Tokamak Ignition/Burn Experimental Reactor, Next European Torus, Fusion Experimental Reactor, International Tokamak Reactor, and AC Tokamak Reactor, can reach ignition with realistic profile parameters and an L-mode scaling law

Calendar year 1996 annual groundwater monitoring report for the Chestnut Ridge Hydrogeologic Regime at the U.S. Department of Energy Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-02-01

This annual monitoring report contains groundwater and surface water monitoring data obtained in the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime) during calendar year (CY) 1996. The Chestnut Ridge Regime encompasses a section of Chestnut Ridge west of Scarboro Road and east of an unnamed drainage feature southwest of the US Department of Energy (DOE) Oak Ridge Y-12 Plant (unless otherwise noted, directions are in reference to the Y-12 Plant administrative grid). The Chestnut Ridge Regime contains several sites used for management of hazardous and nonhazardous wastes associated with plant operations. Groundwater and surface water quality monitoring associated with these waste management sites is performed under the auspices of the Y-12 Plant Groundwater Protection Program (GWPP). Included in this annual monitoring report are the groundwater monitoring data obtained in compliance with the Resource Conservation and Recovery Act (RCRA) Post-Closure Permit for the Chestnut Ridge Regime (post-closure permit) issued by the Tennessee Department of Environment and Conservation (TDEC) in June 1996. Besides the signed certification statement and the RCRA facility information summarized below, condition II.C.6 of the post-closure permit requires annual reporting of groundwater monitoring activities, inclusive of the analytical data and results of applicable data evaluations, performed at three RCRA hazardous waste treatment, storage, or disposal (TSD) units: the Chestnut Ridge Sediment Disposal Basin (Sediment Disposal Basin), the Chestnut Ridge Security Pits (Security Pits), and Kerr Hollow Quarry

The effectiveness of adhesives on the retention of mandibular free end saddle partial dentures: An in vitro study.

Science.gov (United States)

Quiney, Daniel; Nishio Ayre, Wayne; Milward, Paul

2017-07-01

Existing in vitro methods for testing denture adhesives do not fully replicate the complex oral geometries and environment; and in vivo methods are qualitative, prone to bias and not easily reproducible. The purpose of this study was to develop a novel, quantitative and more accurate model to test the effect of adhesives on the retentive force of mandibular free end saddle partial dentures. An in vitro model was developed based on an anatomically accurate cast of a clinical case. Experimentally, the amount of adhesive was varied (0.2g-1g) and the tensile force required for displacement was measured. Different commercially available adhesives were then tested at the optimum volume using the in vitro model. A 3D finite element model of the denture was used to assess how the forces to induce denture displacement varied according to the position of the force along the saddle length. The mass of adhesive was found to significantly alter retention forces, with 0.4-0.7g being the optimum range for this particular scenario. Use of adhesives significantly improved mandibular free end saddle partial denture retention with the worst performing adhesive increasing retention nine-fold whilst the best performing adhesive increased retention twenty three-fold. The finite element model revealed that 77% more force was required to displace the denture by positioning forces towards the mesial end of the saddle compared to the distal end. An in vitro denture adhesive model was developed, which demonstrated that mass of adhesive plays a significant role in enhancing denture retention and supported the design principle of placing as few teeth as clinically necessary on the distal end of the free end saddles. Limiting the position of teeth on free end saddles to the mesial and mid portion of the saddle will reduce displacements caused by mastication. The movement of mandibular free end saddle partial dentures can be restricted with the use of denture adhesives. Altering the mass of

Rotating saddle trap as Foucault's pendulum

Science.gov (United States)

Kirillov, Oleg N.; Levi, Mark

2016-01-01

One of the many surprising results found in the mechanics of rotating systems is the stabilization of a particle in a rapidly rotating planar saddle potential. Besides the counterintuitive stabilization, an unexpected precessional motion is observed. In this note, we show that this precession is due to a Coriolis-like force caused by the rotation of the potential. To our knowledge, this is the first example where such a force arises in an inertial reference frame. We also propose a simple mechanical demonstration of this effect.

Complex saddle points and the sign problem in complex Langevin simulation

International Nuclear Information System (INIS)

Hayata, Tomoya; Hidaka, Yoshimasa; Tanizaki, Yuya

2016-01-01

We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.

Volcanism and hydrothermalism on a hotspot-influenced ridge: Comparing Reykjanes Peninsula and Reykjanes Ridge, Iceland

Science.gov (United States)

Pałgan, Dominik; Devey, Colin W.; Yeo, Isobel A.

2017-12-01

Current estimates indicate that the number of high-temperature vents (one of the primary pathways for the heat extraction from the Earth's mantle) - at least 1 per 100 km of axial length - scales with spreading rate and should scale with crustal thickness. But up to present, shallow ridge axes underlain by thick crust show anomalously low incidences of high-temperature activity. Here we compare the Reykjanes Ridge, an abnormally shallow ridge with thick crust and only one high-temperature vent known over 900 km axial length, to the adjacent subaerial Reykjanes Peninsula (RP), which is characterized by high-temperature geothermal sites confined to four volcanic systems transected by fissure swarms with young (Holocene) volcanic activity, multiple faults, cracks and fissures, and continuous seismic activity. New high-resolution bathymetry (gridded at 60 m) of the Reykjanes Ridge between 62°30‧N and 63°30‧N shows seven Axial Volcanic Ridges (AVR) that, based on their morphology, geometry and tectonic regime, are analogues for the volcanic systems and fissure swarms on land. We investigate in detail the volcano-tectonic features of all mapped AVRs and show that they do not fit with the previously suggested 4-stage evolution model for AVR construction. Instead, we suggest that AVR morphology reflects the robust or weak melt supply to the system and two (or more) eruption mechanisms may co-exist on one AVR (in contrast to 4-stage evolution model). Our interpretations indicate that, unlike on the Reykjanes Peninsula, faults on and around AVRs do not cluster in orientation domains but all are subparallel to the overall strike of AVRs (orthogonal to spreading direction). High abundance of seamounts shows that the region centered at 62°47‧N and 25°04‧W (between AVR-5 and -6) is volcanically robust while the highest fault density implies that AVR-1 and southern part of AVR-6 rather undergo period of melt starvation. Based on our observations and interpretations we

Maximum Attainable Accuracy of Inexact Saddle Point Solvers

Czech Academy of Sciences Publication Activity Database

Jiránek, P.; Rozložník, Miroslav

2008-01-01

Roč. 29, č. 4 (2008), s. 1297-1321 ISSN 0895-4798 R&D Projects: GA MŠk 1M0554; GA AV ČR 1ET400300415 Institutional research plan: CEZ:AV0Z10300504 Keywords : saddle point problems * Schur complement reduction * null-space projection method * rounding error analysis Subject RIV: BA - General Mathematics Impact factor: 1.328, year: 2008

Acceleration of Alveolar Ridge Augmentation Using a Low Dose of Recombinant Human Bone Morphogenetic Protein-2 Loaded on a Resorbable Bioactive Ceramic.

Science.gov (United States)

Fahmy, Rania A; Mahmoud, Naguiba; Soliman, Samia; Nouh, Samir R; Cunningham, Larry; El-Ghannam, Ahmed

2015-12-01

The aim of the present study was to evaluate the effect of a porous silica-calcium phosphate composite (SCPC50) loaded with and without recombinant human bone morphogenetic protein-2 (rhBMP-2) on alveolar ridge augmentation in saddle-type defects. Micro-granules of SCPC50 resorbable bioactive ceramic were coated with rhBMP-2 10 mg and then implanted into a saddle-type defect (12 × 7 mm) in a dog mandible and covered with a collagen membrane. Control groups included defects grafted with SCPC50 granules without rhBMP-2 and un-grafted defects. Bone healing was evaluated at 8 and 16 weeks using histologic and histomorphometric techniques. The increase in bone height and total defect fill were assessed for each specimen using the ImageJ 1.46 program. The release kinetics of rhBMP-2 was determined in vitro. The height of the bone in the grafted defects and the total defect fill were statistically analyzed. SCPC50 enhanced alveolar ridge augmentation as indicated by the increased vertical bone height, bone surface area, and bone volume after 16 weeks. SCPC50-rhBMP-2 provided a sustained release profile of a low effective dose (BMP-2 4.6 ± 1.34 pg/mL per hour) during the 1- to 21-day period. The slow rate of release of rhBMP-2 from SCPC50 accelerated synchronized complete bone regeneration and graft material resorption in 8 weeks. Successful rapid reconstruction of the alveolar ridge by SCPC50 and SCPC50-rhBMP-2 occurred without any adverse excessive bone formation, inflammation, or fluid-filled voids. Results of this study suggest that SCPC50 is an effective graft material to preserve the alveolar ridge after tooth extraction. Coating SCPC50-rhBMP-2 further accelerated bone regeneration and a considerable increase in vertical bone height. These findings make SCPC50 the primary choice as a carrier for rhBMP-2. SCPC50-rhBMP-2 can serve as an alternative to autologous bone grafting. Published by Elsevier Inc.

Identification of a mutation that is associated with the saddle tan and black-and-tan phenotypes in Basset Hounds and Pembroke Welsh Corgis.

Science.gov (United States)

Dreger, Dayna L; Parker, Heidi G; Ostrander, Elaine A; Schmutz, Sheila M

2013-01-01

The causative mutation for the black-and-tan (a (t) ) phenotype in dogs was previously shown to be a SINE insertion in the 5' region of Agouti Signaling Protein (ASIP). Dogs with the black-and-tan phenotype, as well as dogs with the saddle tan phenotype, genotype as a (t) /_ at this locus. We have identified a 16-bp duplication (g.1875_1890dupCCCCAGGTCAGAGTTT) in an intron of hnRNP associated with lethal yellow (RALY), which segregates with the black-and-tan phenotype in a group of 99 saddle tan and black-and-tan Basset Hounds and Pembroke Welsh Corgis. In these breeds, all dogs with the saddle tan phenotype had RALY genotypes of +/+ or +/dup, whereas dogs with the black-and-tan phenotype were homozygous for the duplication. The presence of an a (y) /_ fawn or e/e red genotype is epistatic to the +/_ saddle tan genotype. Genotypes from 10 wolves and 1 coyote indicated that the saddle tan (+) allele is the ancestral allele, suggesting that black-and-tan is a modification of saddle tan. An additional 95 dogs from breeds that never have the saddle tan phenotype have all three of the possible RALY genotypes. We suggest that a multi-gene interaction involving ASIP, RALY, MC1R, DEFB103, and a yet-unidentified modifier gene is required for expression of saddle tan.

Unified analysis of preconditioning methods for saddle point matrices

Czech Academy of Sciences Publication Activity Database

Axelsson, Owe

2015-01-01

Roč. 22, č. 2 (2015), s. 233-253 ISSN 1070-5325 R&D Projects: GA MŠk ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : saddle point problems * preconditioning * spectral properties Subject RIV: BA - General Mathematics Impact factor: 1.431, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/nla.1947/pdf

Spatial variations in isostatic compensation mechanisms of the Ninetyeast Ridge and their tectonic significance

Digital Repository Service at National Institute of Oceanography (India)

Sreejith, K.M.; Krishna, K.S.

, and gravity (shipborne and satellite) data along 72 closely spaced transects and 17 overlapping grids on the NER are analyzed and modeled to determine the effective elastic thickness (Te) beneath the entire ridge. The results of 2-D and 3-D flexural modeling...

Surface plasma source with saddle antenna radio frequency plasma generator.

Science.gov (United States)

Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R

2012-02-01

A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing.

Localized saddle-point search and application to temperature-accelerated dynamics

Energy Technology Data Exchange (ETDEWEB)

Shim, Yunsic; Amar, Jacques G. [Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606 (United States); Callahan, Nathan B. [Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606 (United States); Department of Physics, Indiana University, Bloomington, Indiana 47405 (United States)

2013-03-07

We present a method for speeding up temperature-accelerated dynamics (TAD) simulations by carrying out a localized saddle-point (LSAD) search. In this method, instead of using the entire system to determine the energy barriers of activated processes, the calculation is localized by only including a small chunk of atoms around the atoms directly involved in the transition. Using this method, we have obtained N-independent scaling for the computational cost of the saddle-point search as a function of system size N. The error arising from localization is analyzed using a variety of model systems, including a variety of activated processes on Ag(100) and Cu(100) surfaces, as well as multiatom moves in Cu radiation damage and metal heteroepitaxial growth. Our results show significantly improved performance of TAD with the LSAD method, for the case of Ag/Ag(100) annealing and Cu/Cu(100) growth, while maintaining a negligibly small error in energy barriers.

Effect of saddle-point anisotropy on point-defect drift-diffusion into straight dislocations

International Nuclear Information System (INIS)

Skinner, B.C.; Woo, C.H.

1983-02-01

Effects on point-defect drift-diffusion in the strain fields of edge or screw dislocations, due to the anisotropy of the point defect in its saddle-point configuration, are investigated. Expressions for sink strength and bias that include the saddle-point shape effect are derived, both in the absence and presence of an externally applied stress. These are found to depend on intrinsic parameters such as the relaxation volume and the saddle-point shape of the point defects, and extrinsic parameters such as temperature and the magnitude and direction of the externally applied stress with respect to the line direction and Burgers vector direction of the dislocation. The theory is applied to fcc copper and bcc iron. It is found that screw dislocations are biased sinks and that the stress-induced bias differential for the edge dislocations depends much more on the line direction than the Burgers vector direction. Comparison with the stress-induced bias differential due to the usual SIPA effect is made. It is found that the present effect causes a bias differential that is more than an order of magnitude larger

Power inverter design for ASDEX Upgrade saddle coils

Energy Technology Data Exchange (ETDEWEB)

Teschke, M., E-mail: teschke@ipp.mpg.de [Max Planck Institute for Plasma Physics, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Suttrop, W.; Rott, M. [Max Planck Institute for Plasma Physics, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany)

2013-10-15

Highlights: ► A cost effective inverter topology for AUG's 16 in-vessel saddle coils has been found. ► Use of commercially available power modules is possible. ► Exchange of reactive power between multiple inverters is possible. ► Influence of electromagnetic noise to AUG's diagnostics was measured. ► Gas insulation of electric feed through significantly depends on magnetic fields. It is protected by fast turn-off circuit. -- Abstract: A set of 16 in-vessel saddle coils has been installed in the ASDEX Upgrade (AUG) experiment since the end of 2011 [1]. To achieve full performance, it is necessary to operate them with alternating current (AC) of arbitrary waveforms. To generate spatially resolved magnetic fields, it is required to allocate separate power inverters to every single coil. Therefore, different topologies are analyzed and compared. Studies of the commutation behavior of power stages, different pulse width modulation (PWM) schemes and single-phase-to-earth fault detection are executed. Experiments to evaluate the electromagnetic interference (EMI) of possible inverter topologies on the AUG diagnostics are done as well. A special focus is put on the feasibility of analyzed topologies using industrially available and fully assembled “power modules” to minimize development effort and costs.

From the CERN web: grid computing, night shift, ridge effect and more

CERN Multimedia

2015-01-01

This section highlights articles, blog posts and press releases published in the CERN web environment over the past weeks. This way, you won’t miss a thing...   Schoolboy uses grid computing to analyse satellite data 9 December - by David Lugmayer  At just 16, Cal Hewitt, a student at Simon Langton Grammar School for Boys in the United Kingdom became the youngest person to receive grid certification – giving him access to huge grid-computing resources. Hewitt uses these resources to help analyse data from the LUCID satellite detector, which a team of students from the school launched into space last year. Continue to read…    Night shift in the CMS Control Room (Photo: Andrés Delannoy). On Seagull Soup and Coffee Deficiency: Night Shift at CMS 8 December – CMS Collaboration More than half a year, a school trip to CERN, and a round of 13 TeV collisions later, the week-long internship we completed at CMS over E...

A novel grid multiwing chaotic system with only non-hyperbolic equilibria

Science.gov (United States)

Zhang, Sen; Zeng, Yicheng; Li, Zhijun; Wang, Mengjiao; Xiong, Le

2018-05-01

The structure of the chaotic attractor of a system is mainly determined by the nonlinear functions in system equations. By using a new saw-tooth wave function and a new stair function, a novel complex grid multiwing chaotic system which belongs to non-Shil'nikov chaotic system with non-hyperbolic equilibrium points is proposed in this paper. It is particularly interesting that the complex grid multiwing attractors are generated by increasing the number of non-hyperbolic equilibrium points, which are different from the traditional methods of realising multiwing attractors by adding the index-2 saddle-focus equilibrium points in double-wing chaotic systems. The basic dynamical properties of the new system, such as dissipativity, phase portraits, the stability of the equilibria, the time-domain waveform, power spectrum, bifurcation diagram, Lyapunov exponents, and so on, are investigated by theoretical analysis and numerical simulations. Furthermore, the corresponding electronic circuit is designed and simulated on the Multisim platform. The Multisim simulation results and the hardware experimental results are in good agreement with the numerical simulations of the same system on Matlab platform, which verify the feasibility of this new grid multiwing chaotic system.

Spike-adding in parabolic bursters: The role of folded-saddle canards

Science.gov (United States)

Desroches, Mathieu; Krupa, Martin; Rodrigues, Serafim

2016-09-01

The present work develops a new approach to studying parabolic bursting, and also proposes a novel four-dimensional canonical and polynomial-based parabolic burster. In addition to this new polynomial system, we also consider the conductance-based model of the Aplysia R15 neuron known as the Plant model, and a reduction of this prototypical biophysical parabolic burster to three variables, including one phase variable, namely the Baer-Rinzel-Carillo (BRC) phase model. Revisiting these models from the perspective of slow-fast dynamics reveals that the number of spikes per burst may vary upon parameter changes, however the spike-adding process occurs in an explosive fashion that involves special solutions called canards. This spike-adding canard explosion phenomenon is analysed by using tools from geometric singular perturbation theory in tandem with numerical bifurcation techniques. We find that the bifurcation structure persists across all considered systems, that is, spikes within the burst are incremented via the crossing of an excitability threshold given by a particular type of canard orbit, namely the true canard of a folded-saddle singularity. However there can be a difference in the spike-adding transitions in parameter space from one case to another, according to whether the process is continuous or discontinuous, which depends upon the geometry of the folded-saddle canard. Using these findings, we construct a new polynomial approximation of the Plant model, which retains all the key elements for parabolic bursting, including the spike-adding transitions mediated by folded-saddle canards. Finally, we briefly investigate the presence of spike-adding via canards in planar phase models of parabolic bursting, namely the theta model by Ermentrout and Kopell.

Krylov Subspace Methods for Saddle Point Problems with Indefinite Preconditioning

Czech Academy of Sciences Publication Activity Database

Rozložník, Miroslav; Simoncini, V.

2002-01-01

Roč. 24, č. 2 (2002), s. 368-391 ISSN 0895-4798 R&D Projects: GA ČR GA101/00/1035; GA ČR GA201/00/0080 Institutional research plan: AV0Z1030915 Keywords : saddle point problems * preconditioning * indefinite linear systems * finite precision arithmetic * conjugate gradients Subject RIV: BA - General Mathematics Impact factor: 0.753, year: 2002

On the Use of the Main-sequence Knee (Saddle) to Measure Globular Cluster Ages

Science.gov (United States)

Saracino, S.; Dalessandro, E.; Ferraro, F. R.; Lanzoni, B.; Origlia, L.; Salaris, M.; Pietrinferni, A.; Geisler, D.; Kalirai, J. S.; Correnti, M.; Cohen, R. E.; Mauro, F.; Villanova, S.; Moni Bidin, C.

2018-06-01

In this paper, we review the operational definition of the so-called main-sequence knee (MS-knee), a feature in the color-magnitude diagram (CMD) occurring at the low-mass end of the MS. The magnitude of this feature is predicted to be independent of age at fixed chemical composition. For this reason, its difference in magnitude with respect to the MS turn-off (MS-TO) point has been suggested as a possible diagnostic to estimate absolute globular cluster (GC) ages. We first demonstrate that the operational definition of the MS-knee currently adopted in the literature refers to the inflection point of the MS (which we here more appropriately named MS-saddle), a feature that is well distinct from the knee and which cannot be used as its proxy. The MS-knee is only visible in near-infrared CMDs, while the MS-saddle can be also detected in optical–NIR CMDs. By using different sets of isochrones, we then demonstrate that the absolute magnitude of the MS-knee varies by a few tenths of a dex from one model to another, thus showing that at the moment stellar models may not capture the full systematic error in the method. We also demonstrate that while the absolute magnitude of the MS-saddle is almost coincident in different models, it has a systematic dependence on the adopted color combinations which is not predicted by stellar models. Hence, it cannot be used as a reliable reference for absolute age determination. Moreover, when statistical and systematic uncertainties are properly taken into account, the difference in magnitude between the MS-TO and the MS-saddle does not provide absolute ages with better accuracy than other methods like the MS-fitting.

On Signed Incomplete Cholesky Factorization Preconditioners for Saddle-Point Systems

Czech Academy of Sciences Publication Activity Database

Scott, J.; Tůma, Miroslav

2014-01-01

Roč. 36, č. 6 (2014), A2984-A3010 ISSN 1064-8275 R&D Projects: GA ČR GA13-06684S Grant - others:EPSRC(GB) EP/I013067/1 Program:GA Institutional support: RVO:67985807 Keywords : sparse matrices * sparse linear systems * indefinite symmetric systems * saddle-point systems * iterative solvers * preconditioning * incomplete Cholesky factorization Subject RIV: BA - General Mathematics Impact factor: 1.854, year: 2014

Regional anesthesia in transurethral resection of prostate (TURP surgery: A comparative study between saddle block and subarachnoid block

Directory of Open Access Journals (Sweden)

Susmita Bhattacharyya

2015-01-01

Full Text Available Background: Spinal anesthesia is the technique of choice in transurethral resection of prostate (TURP. The major complication of spinal technique is risk of hypotension. Saddle block paralyzed pelvic muscles and sacral nerve roots and hemodynamic derangement is less. Aims and objectives: To compare the hemodynamic changes and adequate surgical condition between saddle block and subarachnoid block for TURP. Material and methods: Ninety patients of aged between 50 to 70 years of ASA-PS I, II scheduled for TURP were randomly allocated into 2 groups of 45 in each group. Group A patients were received spinal (2 ml of hyperbaric bupivacaine and Group B were received saddle block (2 ml of hyperbaric bupivacaine. Baseline systolic, diastolic and mean arterial pressure, heart rate, oxygen saturation were recorded and measured subsequently. The height of block was noted in both groups. Hypotension was corrected by administration of phenylephrine 50 mcg bolus and total requirement of vasopressor was noted. Complications (volume overload, TURP syndrome etc. were noted. Results: Incidence of hypotension and vasopressor requirement was less (P < 0.01 in Gr B patients.Adequate surgical condition was achieved in both groups. There was no incidence of volume overload, TURP syndrome, and bladder perforation. Conclusion: TURP can be safely performed under saddle block without hypotension and less vasopressor requirement.

Non-invasive Investigation and Management of Aortic Saddle Embolus in a 7-Month-Old Infant

International Nuclear Information System (INIS)

O'Connell, Martin J.; Duff, Desmond F.; Hayes, Roisin M.

2002-01-01

There are few reports in the literature on the ultrasound appearance of aortic saddle embolus, and none relating to small children. This unusual condition is usually diagnosed angiographically. The purpose of this report is to show how effectively high-frequency ultrasound can identify a saddle embolus with its associated collateral circulation in a young child, and to demonstrate its usefulness in monitoring the efficacy of treatment. In this case the embolus occurred as a complication of parvovirus B19 myocarditis and was diagnosed and followed up entirely by ultrasound examination,with no invasive procedure performed. The early development of an extensive collateral circulation prevented distal tissue necrosis and allowed a conservative approach to management

Limiting Accuracy of Segregated Solution Methods for Nonsymmetric Saddle Point Problems

Czech Academy of Sciences Publication Activity Database

Jiránek, P.; Rozložník, Miroslav

Roc. 215, c. 1 (2008), s. 28-37 ISSN 0377-0427 R&D Projects: GA MŠk 1M0554; GA AV ČR 1ET400300415 Institutional research plan: CEZ:AV0Z10300504 Keywords : saddle point problems * Schur complement reduction method * null-space projection method * rounding error analysis Subject RIV: BA - General Mathematics Impact factor: 1.048, year: 2008

Saddle-shaped reticulate Nummulites from Early Oligocene rocks of Khari area, SW Kutch, India

Science.gov (United States)

Sengupta, S.; Sarkar, Sampa; Mukhopadhyay, S.

2011-04-01

Saddle-shaped reticulate Nummulites from the Early Oligocene rocks of Khari area, SW Kutch, India is reported here for the first time. Unusual shape of this Nummulites is due to the curved nature of the coiling plane, indicating space constrained postembryonic test growth. With regular development of chambers, septa and septal filaments, the saddle-shaped Nummulites constitutes the third morphotype of N. cf. fichteli Michelotti form A. Other morphotypes of the species reported earlier include inflated lenticular and conical tests. Multiple morphotypes of N. cf. fichteli form A indicates varied test growth in response to substrate conditions. Morphological variability exhibited by N. cf. fichteli form A from Kutch and some Early Oligocene reticulate Nummulites from the Far East are comparable. This faunal suite is morphologically distinct from the contemporary reticulate Nummulites of the European localities.

Large N saddle formulation of quadratic building block theories

International Nuclear Information System (INIS)

Halpern, M.B.

1980-01-01

I develop a large N saddle point formulation for the broad class of 'theories of quadratic building blocks'. Such theories are those on which the sums over internal indices are contained in quadratic building blocks, e.g. PHI 2 = Σsup(N)sub(a-1)PHi sup(a)sup(a). The formulation applies as well to fermions, derivative coupling and non-polynomial interactions. In a related development, closed Schwinger-Dyson equations for Green functions of the building blocks are derived and solved for large N. (orig.)

Saddle-points of a two dimensional random lattice theory

International Nuclear Information System (INIS)

Pertermann, D.

1985-07-01

A two dimensional random lattice theory with a free massless scalar field is considered. We analyse the field theoretic generating functional for any given choice of positions of the lattice sites. Asking for saddle-points of this generating functional with respect to the positions we find the hexagonal lattice and a triangulated version of the hypercubic lattice as candidates. The investigation of the neighbourhood of a single lattice site yields triangulated rectangles and regular polygons extremizing the above generating functional on the local level. (author)

Computation of saddle-type slow manifolds using iterative methods

DEFF Research Database (Denmark)

Kristiansen, Kristian Uldall

2015-01-01

with respect to , appropriate estimates are directly attainable using the method of this paper. The method is applied to several examples, including a model for a pair of neurons coupled by reciprocal inhibition with two slow and two fast variables, and the computation of homoclinic connections in the Fitz......This paper presents an alternative approach for the computation of trajectory segments on slow manifolds of saddle type. This approach is based on iterative methods rather than collocation-type methods. Compared to collocation methods, which require mesh refinements to ensure uniform convergence...

Saddle-splay screening and chiral symmetry breaking in toroidal nematics

OpenAIRE

Koning, Vinzenz; van Zuiden, Benjamin C.; Kamien, Randall D.; Vitelli, Vincenzo

2013-01-01

We present a theoretical study of director fields in toroidal geometries with degenerate planar boundary conditions. We find spontaneous chirality: despite the achiral nature of nematics the director configuration show a handedness if the toroid is thick enough. In the chiral state the director field displays a double twist, whereas in the achiral state there is only bend deformation. The critical thickness increases as the difference between the twist and saddle-splay moduli grows. A positiv...

Neutron Science TeraGrid Gateway

International Nuclear Information System (INIS)

Lynch, Vickie E.; Chen, Meili; Cobb, John W.; Kohl, James Arthur; Miller, Stephen D.; Speirs, David A.; Vazhkudai, Sudharshan S.

2010-01-01

The unique contributions of the Neutron Science TeraGrid Gateway (NSTG) are the connection of national user facility instrument data sources to the integrated cyberinfrastructure of the National Science FoundationTeraGrid and the development of a neutron science gateway that allows neutron scientists to use TeraGrid resources to analyze their data, including comparison of experiment with simulation. The NSTG is working in close collaboration with the Spallation Neutron Source (SNS) at Oak Ridge as their principal facility partner. The SNS is a next-generation neutron source. It has completed construction at a cost of $1.4 billion and is ramping up operations. The SNS will provide an order of magnitude greater flux than any previous facility in the world and will be available to all of the nation's scientists, independent of funding source, on a peer-reviewed merit basis. With this new capability, the neutron science community is facing orders of magnitude larger data sets and is at a critical point for data analysis and simulation. There is a recognized need for new ways to manage and analyze data to optimize both beam time and scientific output. The TeraGrid is providing new capabilities in the gateway for simulations using McStas and a fitting service on distributed TeraGrid resources to improved turnaround. NSTG staff are also exploring replicating experimental data in archival storage. As part of the SNS partnership, the NSTG provides access to gateway support, cyberinfrastructure outreach, community development, and user support for the neutron science community. This community includes not only SNS staff and users but extends to all the major worldwide neutron scattering centers.

Binary nucleation kinetics. III. Transient behavior and time lags

International Nuclear Information System (INIS)

Wyslouzil, B.E.; Wilemski, G.

1996-01-01

Transient binary nucleation is more complex than unary because of the bidimensionality of the cluster formation kinetics. To investigate this problem qualitatively and quantitatively, we numerically solved the birth-death equations for vapor-to-liquid phase transitions. Our previous work showed that the customary saddle point and growth path approximations are almost always valid in steady state gas phase nucleation and only fail if the nucleated solution phase is significantly nonideal. Now, we demonstrate that in its early transient stages, binary nucleation rarely, if ever, occurs via the saddle point. This affects not only the number of particles forming but their composition and may be important for nucleation in glasses and other condensed mixtures for which time scales are very long. Before reaching the state of saddle point nucleation, most binary systems pass through a temporary stage in which the region of maximum flux extends over a ridge on the free energy surface. When ridge crossing nucleation is the steady state solution, it thus arises quite naturally as an arrested intermediate state that normally occurs in the development of saddle point nucleation. While the time dependent and steady state distributions of the fluxes and concentrations for each binary system are strongly influenced by the gas composition and species impingement rates, the ratio of nonequilibrium to equilibrium concentrations has a quasiuniversal behavior that is determined primarily by the thermodynamic properties of the liquid mixture. To test our quantitive results of the transient behavior, we directly calculated the time lag for the saddle point flux and compared it with the available analytical predictions. Although the analytical results overestimate the time lag by factors of 1.2-5, they should be adequate for purposes of planning experiments. We also found that the behavior of the saddle point time lag can indicate when steady state ridge crossing nucleation will occur

Recent progress in fission at saddle point and scission point

International Nuclear Information System (INIS)

Blons, J.; Paya, D.; Signarbieux, C.

High resolution measurements of 230 Th and 232 Th fission cross sections for neutrons exhibit a fine structure. Such a structure is interpreted as a superposition of two rotational bands in the third, asymmetric, well of the fission barrier. The fragment mass distribution in the thermal fission of 235 U and 233 U does not show any even-odd effect, even at the highest kinetic energies. This is the mark of a strong viscosity in the descent from saddle point to scission point [fr

On the late-time behavior of Virasoro blocks and a classification of semiclassical saddles

Energy Technology Data Exchange (ETDEWEB)

Fitzpatrick, A. Liam [Department of Physics, Boston University,Commonwealth Avenue, Boston, MA 02215 (United States); Kaplan, Jared [Department of Physics and Astronomy, Johns Hopkins University,Charles Street, Baltimore, MD 21218 (United States)

2017-04-12

Recent work has demonstrated that black hole thermodynamics and information loss/restoration in AdS{sub 3}/CFT{sub 2} can be derived almost entirely from the behavior of the Virasoro conformal blocks at large central charge, with relatively little dependence on the precise details of the CFT spectrum or OPE coefficients. Here, we elaborate on the non-perturbative behavior of Virasoro blocks by classifying all ‘saddles’ that can contribute for arbitrary values of external and internal operator dimensions in the semiclassical large central charge limit. The leading saddles, which determine the naive semiclassical behavior of the Virasoro blocks, all decay exponentially at late times, and at a rate that is independent of internal operator dimensions. Consequently, the semiclassical contribution of a finite number of high-energy states cannot resolve a well-known version of the information loss problem in AdS{sub 3}. However, we identify two infinite classes of sub-leading saddles, and one of these classes does not decay at late times.

Ridge augmentation using recombinant human fibroblast growth factor-2 with biodegradable gelatin sponges incorporating β-tricalcium phosphate: a preclinical study in dogs.

Science.gov (United States)

Hoshi, S; Akizuki, T; Matsuura, T; Ikawa, T; Kinoshita, A; Oda, S; Tabata, Y; Matsui, M; Izumi, Y

2016-02-01

Fibroblast growth factor-2 (FGF-2) regulates the proliferation and differentiation of osteogenic cells, resulting in the promotion of bone formation. Biodegradable gelatin sponges incorporating β-tricalcium phosphate (β-TCP) have been reported as a scaffold, which has the ability to control growth factor release, offering sufficient mechanical strength and efficient migration of mesenchymal cells. In this study, we evaluated the effects of the combined use of recombinant human FGF-2 (rhFGF-2) and gelatin/β-TCP sponge on ridge augmentation in dogs. Six male beagle dogs were used in this study. Twelve wk after tooth extraction, bilateral 10 × 5 mm (width × depth) saddle-type defects were created 3 mm apart from the mesial side of the maxillary canine. At the experimental sites, the defects were filled with gelatin/β-TCP sponge infiltrated with 0.3% rhFGF-2, whereas gelatin/β-TCP sponge infiltrated with saline was applied to the control sites. Eight wk after surgery, qualitative and quantitative analyses were performed. There were no signs of clinical inflammation at 8 wk after surgery. Histometric measurements revealed that new bone height at the experimental sites (2.98 ± 0.65 mm) was significantly greater than that at the control sites (1.56 ± 0.66 mm; p = 0.004). The total tissue height was greater at the experimental sites (6.62 ± 0.66 mm) than that at the control sites (5.95 ± 0.74 mm), although there was no statistical significant difference (p = 0.051). Cast model measurements revealed that the residual defect height at the experimental sites (2.31 ± 0.50 mm) was significantly smaller than that at the control sites (3.51 ± 0.78 mm; p = 0.012). The combined use of rhFGF-2 and gelatin/β-TCP sponge promotes ridge augmentation in canine saddle-type bone defects. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Remedial Investigation Work Plan for Chestnut Ridge Operable Unit 1 (Chestnut Ridge Security Pits) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-03-01

This document outlines the activities necessary to conduct a Remedial Investigation (RI) of the Chestnut Ridge Security Pits (CRSP) at the Oak Ridge Y-12 Plant. The CRSP, also designated Chestnut Ridge Operable Unit (OU) 1, is one of four OUs along Chestnut Ridge on the Oak Ridge Reservation (ORR). The purpose of the RI is to collect data to (1) evaluate the nature and extent of known and suspected contaminants, (2) support an Ecological Risk Assessment (ERA) and a Human Health Risk Assessment (HHRA), (3) support the feasibility study in the development and analysis of remedial alternatives, and (4) ultimately, develop a Record of Decision (ROD) for the site. This chapter summarizes the regulatory background of environmental investigation on the ORR and the approach currently being followed and provides an overview of the RI to be conducted at the CRSP. Subsequent chapters provide details on site history, sampling activities, procedures and methods, quality assurance (QA), health and safety, and waste management related to the RI

Remedial Investigation Work Plan for Chestnut Ridge Operable Unit 1 (Chestnut Ridge Security Pits) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

1994-03-01

This document outlines the activities necessary to conduct a Remedial Investigation (RI) of the Chestnut Ridge Security Pits (CRSP) at the Oak Ridge Y-12 Plant. The CRSP, also designated Chestnut Ridge Operable Unit (OU) 1, is one of four OUs along Chestnut Ridge on the Oak Ridge Reservation (ORR). The purpose of the RI is to collect data to (1) evaluate the nature and extent of known and suspected contaminants, (2) support an Ecological Risk Assessment (ERA) and a Human Health Risk Assessment (HHRA), (3) support the feasibility study in the development and analysis of remedial alternatives, and (4) ultimately, develop a Record of Decision (ROD) for the site. This chapter summarizes the regulatory background of environmental investigation on the ORR and the approach currently being followed and provides an overview of the RI to be conducted at the CRSP. Subsequent chapters provide details on site history, sampling activities, procedures and methods, quality assurance (QA), health and safety, and waste management related to the RI.

An aerial radiological survey of the Oak Ridge Reservation, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Maurer, R.J.

1993-04-01

An aerial radiological survey of the Oak Ridge Reservation (ORR) and surrounding area in Oak Ridge, Tennessee, was conducted during the period March 30 to April 14,1992. The purpose of the survey was to measure and document the terrestrial radiological environment of the Oak Ridge Reservation for use in environmental management programs and emergency response planning. The aerial survey was flown at an altitude of 150 feet (46 meters) along a series of parallel lines 250 feet (76 meters) apart and included X-10 (Oak Ridge National Laboratory), K-25 (former Gaseous Diffusion Plant), Y-12 (Weapons Production Plant), the Freels Bend Area and Oak Ridge Institute for Science and Education, the East Fork Poplar Creek (100-year floodplain extending from K-25 to Y-12), Elza Gate (former uranium ore storage site located in the city of Oak Ridge), Parcel A, the Clinch River (river banks extending from Melton Hill Dam to the city of Kingston), and the CSX Railroad Tracks (extending from Y-12 to the city of Oak Ridge). The survey encompassed approximately 55 square miles (1 41 square kilometers) of the Oak Ridge Reservation and surrounding area

On preconditioner updates for sequences of saddle-point linear systems

Directory of Open Access Journals (Sweden)

Simone Valentina De

2018-02-01

Full Text Available Updating preconditioners for the solution of sequences of large and sparse saddle- point linear systems via Krylov methods has received increasing attention in the last few years, because it allows to reduce the cost of preconditioning while keeping the efficiency of the overall solution process. This paper provides a short survey of the two approaches proposed in the literature for this problem: updating the factors of a preconditioner available in a block LDLT form, and updating a preconditioner via a limited-memory technique inspired by quasi-Newton methods.

Triangular preconditioners for saddle point problems with a penalty term

Energy Technology Data Exchange (ETDEWEB)

Klawonn, A. [Westfaelische Wilhelms-Universitaet, Muenster (Germany)

1996-12-31

Triangular preconditioners for a class of saddle point problems with a penalty term are considered. An important example is the mixed formulation of the pure displacement problem in linear elasticity. It is shown that the spectrum of the preconditioned system is contained in a real, positive interval, and that the interval bounds can be made independent of the discretization and penalty parameters. This fact is used to construct bounds of the convergence rate of the GMRES method used with an energy norm. Numerical results are given for GMRES and BI-CGSTAB.

The Neutron Science TeraGrid Gateway, a TeraGrid Science Gateway to Support the Spallation Neutron Source

International Nuclear Information System (INIS)

Cobb, John W.; Geist, Al; Kohl, James Arthur; Miller, Stephen D; Peterson, Peter F.; Pike, Gregory; Reuter, Michael A; Swain, William; Vazhkudai, Sudharshan S.; Vijayakumar, Nithya N.

2006-01-01

The National Science Foundation's (NSF's) Extensible Terascale Facility (ETF), or TeraGrid (1) is entering its operational phase. An ETF science gateway effort is the Neutron Science TeraGrid Gateway (NSTG.) The Oak Ridge National Laboratory (ORNL) resource provider effort (ORNL-RP) during construction and now in operations is bridging a large scale experimental community and the TeraGrid as a large-scale national cyberinfrastructure. Of particular emphasis is collaboration with the Spallation Neutron Source (SNS) at ORNL. The U.S. Department of Energy's (DOE's) SNS (2) at ORNL will be commissioned in spring of 2006 as the world's brightest source of neutrons. Neutron science users can run experiments, generate datasets, perform data reduction, analysis, visualize results; collaborate with remotes users; and archive long term data in repositories with curation services. The ORNL-RP and the SNS data analysis group have spent 18 months developing and exploring user requirements, including the creation of prototypical services such as facility portal, data, and application execution services. We describe results from these efforts and discuss implications for science gateway creation. Finally, we show incorporation into implementation planning for the NSTG and SNS architectures. The plan is for a primarily portal-based user interaction supported by a service oriented architecture for functional implementation

Model Selection in Kernel Ridge Regression

DEFF Research Database (Denmark)

Exterkate, Peter

Kernel ridge regression is gaining popularity as a data-rich nonlinear forecasting tool, which is applicable in many different contexts. This paper investigates the influence of the choice of kernel and the setting of tuning parameters on forecast accuracy. We review several popular kernels......, including polynomial kernels, the Gaussian kernel, and the Sinc kernel. We interpret the latter two kernels in terms of their smoothing properties, and we relate the tuning parameters associated to all these kernels to smoothness measures of the prediction function and to the signal-to-noise ratio. Based...... on these interpretations, we provide guidelines for selecting the tuning parameters from small grids using cross-validation. A Monte Carlo study confirms the practical usefulness of these rules of thumb. Finally, the flexible and smooth functional forms provided by the Gaussian and Sinc kernels makes them widely...

Seafloor Characterisation of the Gakkel Ridge using Multibeam Sonar, Backscatter and Sidescan Data

Science.gov (United States)

Hatzky, J.; Schenke, H. W.

2003-04-01

The Gakkel Ridge in the Arctic Ocean was the object of the Arctic Mid-Ocean Ridge Expedition (AMORE) which was carried out by the research icebreakers R/V "Polarstern" (Germany) and USCGC "Healy" (USA) in the boreal summer 2001. This largely unexplored mid-ocean ridge (MOR) is of particular scientific interest due to its volcanic activity and tectonic structure. With spreading rates of 13mm/a in the western and 6 mm/a in the eastern part Gakkel Ridge is the slowest spreading MOR on earth (Michael et al., 2001). The surveyed area which is situated between 82°N / 8°W and 87°N / 75°E has a length of 8890 km and a varying width from 18 to 46 km. The range of measured depths reaches from 566 m on the top of a huge seamount to 5673 m in the central rift valley. Prominent underwater features of remarkable morphologic diversity (e.g. small volcanoes embedded in massive ridge flanks) were discovered in this region. One of the most important goals of the expedition was the compilation of a high resolution grid which serves as basis for a three dimensional digital terrain model (DTM), the derivation of contour lines and the production of bathymetric maps. Accordingly, two hull-mounted multibeam sonars were used for the depth data acquisition: the "Hydrosweep DS-2" system onboard "Polarstern" and the "Seabeam 2112" system onboard "Healy". In order to calculate a combined grid out of two independent data sets different technical specifications of both sonar systems (e.g. frequency, opening angle, number of beams, accuracy) had to be taken into account. Dense sea ice cover made the sonar measurements difficult. Thick floes caused hydroacoustic disturbances that heavily debased the data quality. Outliers and blunders of depths and navigation data had to be corrected in a drawn-out post-processing by appropriate software tools. Both echo sounding systems recorded backscatter information and sidescan data during the entire cruise. Onboard "Polarstern" the sub-bottom profiling

Stable discretization of poroelasticity problems and efficient preconditioners for arising saddle point type matrices

Czech Academy of Sciences Publication Activity Database

Axelsson, Owe; Blaheta, Radim; Byczanski, Petr

2012-01-01

Roč. 15, č. 4 (2012), s. 191-207 ISSN 1432-9360 R&D Projects: GA MŠk ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : poroelasticity * saddle point matrices * preconditioning * stability of discretization Subject RIV: BA - General Mathematics http://link.springer.com/article/10.1007/s00791-013-0209-0

Effects of saddle height on economy and anaerobic power in well-trained cyclists.

Science.gov (United States)

Peveler, Willard W; Green, James M

2011-03-01

In cycling, saddle height adjustment is critical for optimal performance and injury prevention. A 25-35° knee angle is recommended for injury prevention, whereas 109% of inseam, measured from floor to ischium, is recommended for optimal performance. Previous research has demonstrated that these 2 methods produce significantly different saddle heights and may influence cycling performance. This study compared performance between these 2 methods for determining saddle height. Subjects consisted of 11 well-trained (VO2max = 61.55 ± 4.72 ml·kg·min) male cyclists. Subjects completed a total of 8 performance trials consisting of a graded maximal protocol, three 15-minute economy trials, and 4 anaerobic power trials. Dependent measures for economy (VO2, heart rate, and rating of perceived exertion) and anaerobic power (peak power and mean power) were compared using repeated measures analysis of variance (α = 0.05). VO2 was significantly lower (reflecting greater economy) at a 25° knee angle (44.77 ± 6.40 ml·kg·min) in comparison to a 35° knee angle (45.22 ± 6.79 ml·kg·min) and 109% of inseam (45.98 ± 5.33 ml·kg·min). Peak power at a 25° knee angle (1,041.55 ± 168.72 W) was significantly higher in relation to 109% of inseam (1,002.05 ± 147.65 W). Mean power at a 25° knee angle (672.37 ± 90.21 W) was significantly higher in relation to a 35° knee angle (654.71 ± 80.67 W). Mean power was significantly higher at 109% of inseam (662.86 ± 79.72 W) in relation to a 35° knee angle (654.71 ± 80.67 W). Use of 109% of inseam fell outside the recommended 25-35° range 73% of the time. Use of 25° knee angle appears to provide optimal performance while keeping knee angle within the recommended range for injury prevention.

On the trajectories of CRL...LR...R orbits, their period-doubling cascades and saddle-node bifurcation cascades

International Nuclear Information System (INIS)

Cerrada, Lucia; San Martin, Jesus

2011-01-01

In this Letter, it is shown that from a two region partition of the phase space of a one-dimensional dynamical system, a p-region partition can be obtained for the CRL...LR...R orbits. That is, permutations associated with symbolic sequences are obtained. As a consequence, the trajectory in phase space is directly deduced from permutation. From this permutation other permutations associated with period-doubling and saddle-node bifurcation cascades are derived, as well as other composite permutations. - Research highlights: → Symbolic sequences are the usual topological approach to dynamical systems. → Permutations bear more physical information than symbolic sequences. → Period-doubling cascade permutations associated with original sequences are obtained. → Saddle-node cascade permutations associated with original sequences are obtained. → Composite permutations are derived.

Domain decomposition method for nonconforming finite element approximations of anisotropic elliptic problems on nonmatching grids

Energy Technology Data Exchange (ETDEWEB)

Maliassov, S.Y. [Texas A& M Univ., College Station, TX (United States)

1996-12-31

An approach to the construction of an iterative method for solving systems of linear algebraic equations arising from nonconforming finite element discretizations with nonmatching grids for second order elliptic boundary value problems with anisotropic coefficients is considered. The technique suggested is based on decomposition of the original domain into nonoverlapping subdomains. The elliptic problem is presented in the macro-hybrid form with Lagrange multipliers at the interfaces between subdomains. A block diagonal preconditioner is proposed which is spectrally equivalent to the original saddle point matrix and has the optimal order of arithmetical complexity. The preconditioner includes blocks for preconditioning subdomain and interface problems. It is shown that constants of spectral equivalence axe independent of values of coefficients and mesh step size.

Thickness of Knox Group overburden on Central Chestnut Ridge, Oak Ridge Reservation

International Nuclear Information System (INIS)

Staub, W.P.; Hopkins, R.A.

1984-05-01

The thickness of residual soil overlying the Knox Group along Central Chestnut Ridge was estimated by a conventional seismic refraction survey. The purpose of this survey was to identify sites on the Department of Energy's Oak Ridge Reservation where ample overburden exists above the water table for the shallow land burial of low-level radioactive waste. The results of the survey suggest that the upper slopes of the higher ridges in the area have a minimum of 16 to 26 m (52 to 85 ft) of overburden and that the crests of these ridges may have more than 30 m (100 ft). Therefore, it is unlikely that sound bedrock would be encountered during trench excavation [maximum of 10 m (32 ft)] along Central Chestnut Ridge. Also, the relatively low seismic wave velocities measured in the overburden suggest that the water table is generally deep. On the basis of these preliminary results, Central Chestnut Ridge appears to be suitable for further site characterization for the shallow land burial of low-level radioactive waste. 3 references, 5 figures, 1 table

Investment decisions in the South African saddle horse industry / Johannes Hendrik Dreyer

OpenAIRE

Dreyer, Johannes Hendrik

2014-01-01

This study originated in the phenomenon that has been observed in the South African Saddle Horse Industry of substantial investments being made over time in the absence of obvious financial or economic reward. A literature study confirmed that, internationally, investment without obvious financial and economic rewards is not unknown and at the same time it was obvious that it is a rarely studied subject. From the literature study it was also evident that this phenomenon occurs ...

Materials Innovation for Next-Generation T&D Grid Components. Workshop Summary Report

Energy Technology Data Exchange (ETDEWEB)

Taylor, Emmanuel [Energetics Incorporated, Columbia, MD (United States); Kramer, Caroline [Energetics Incorporated, Columbia, MD (United States); Marchionini, Brian [Energetics Incorporated, Columbia, MD (United States); Sabouni, Ridah [Energetics Incorporated, Columbia, MD (United States); Cheung, Kerry [U.S. Department of Energy (DOE), Washington, DC (United States). Office of Electricity Delivery and Energy Reliability (OE); Lee, Dominic F [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-10-01

The Materials Innovations for Next-Generation T&D Grid Components Workshop was co-sponsored by the U.S. Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability and the Oak Ridge National Laboratory (ORNL) and held on August 26 27, 2015, at the ORNL campus in Oak Ridge, Tennessee. The workshop was planned and executed under the direction of workshop co-chair Dr. Kerry Cheung (DOE) and co-chair Dr. Dominic Lee (ORNL). The information contained herein is based on the results of the workshop, which was attended by nearly 50 experts from government, industry, and academia. The research needs and pathways described in this report reflect the expert opinions of workshop participants, but they are not intended to represent the views of the entire electric power community.

Saddle point solutions in Yang-Mills-dilaton theory

International Nuclear Information System (INIS)

Bizon, P.

1992-01-01

The coupling of a dilaton to the SU(2)-Yang-Mills field leads to interesting non-perturbative static spherically symmetric solutions which are studied by mixed analytical and numerical methods. In the abelian sector of the theory there are finite-energy magnetic and electric monopole solutions which saturate the Bogomol'nyi bound. In the nonabelian sector there exist a countable family of globally regular solutions which are purely magnetic but have zero Yang-Mills magnetic charge. Their discrete spectrum of energies is bounded from above by the energy of the abelian magnetic monopole with unit magnetic charge. The stability analysis demonstrates that the solutions are saddle points of the energy functional with increasing number of unstable modes. The existence and instability of these solutions are 'explained' by the Morse-theory argument recently proposed by Sudarsky and Wald. (author)

Quasar Microlensing at High Magnification and the Role of Dark Matter: Enhanced Fluctuations and Suppressed Saddle Points

Science.gov (United States)

Schechter, Paul L.; Wambsganss, Joachim

2002-12-01

Contrary to naive expectation, diluting the stellar component of the lensing galaxy in a highly magnified system with smoothly distributed ``dark'' matter increases rather than decreases the microlensing fluctuations caused by the remaining stars. For a bright pair of images straddling a critical curve, the saddle point (of the arrival time surface) is much more strongly affected than the associated minimum. With a mass ratio of smooth matter to microlensing matter of 4:1, a saddle point with a macromagnification of μ=9.5 will spend half of its time more than a magnitude fainter than predicted. The anomalous flux ratio observed for the close pair of images in MG 0414+0534 is a factor of 5 more likely than computed by Witt, Mao, & Schechter, if the smooth matter fraction is as high as 93%. The magnification probability histograms for macroimages exhibit a distinctly different structure that varies with the smooth matter content, providing a handle on the smooth matter fraction. Enhanced fluctuations can manifest themselves either in the temporal variations of a light curve or as flux ratio anomalies in a single epoch snapshot of a multiply imaged system. While the millilensing simulations of Metcalf & Madau also give larger anomalies for saddle points than for minima, the effect appears to be less dramatic for extended subhalos than for point masses. Moreover, microlensing is distinguishable from millilensing because it will produce noticeable changes in the magnification on a timescale of a decade or less.

Preconditioners for regularized saddle point problems with an application for heterogeneous Darcy flow problems

Czech Academy of Sciences Publication Activity Database

Axelsson, Owe; Blaheta, Radim; Byczanski, Petr; Karátson, J.; Ahmad, B.

2015-01-01

Roč. 280, č. 280 (2015), s. 141-157 ISSN 0377-0427 R&D Projects: GA MŠk ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : preconditioners * heterogeneous coefficients * regularized saddle point Inner–outer iterations * Darcy flow Subject RIV: BA - General Mathematics Impact factor: 1.328, year: 2015 http://www.sciencedirect.com/science/article/pii/S0377042714005238

Saddle Slow Manifolds and Canard Orbits in [Formula: see text] and Application to the Full Hodgkin-Huxley Model.

Science.gov (United States)

Hasan, Cris R; Krauskopf, Bernd; Osinga, Hinke M

2018-04-19

Many physiological phenomena have the property that some variables evolve much faster than others. For example, neuron models typically involve observable differences in time scales. The Hodgkin-Huxley model is well known for explaining the ionic mechanism that generates the action potential in the squid giant axon. Rubin and Wechselberger (Biol. Cybern. 97:5-32, 2007) nondimensionalized this model and obtained a singularly perturbed system with two fast, two slow variables, and an explicit time-scale ratio ε. The dynamics of this system are complex and feature periodic orbits with a series of action potentials separated by small-amplitude oscillations (SAOs); also referred to as mixed-mode oscillations (MMOs). The slow dynamics of this system are organized by two-dimensional locally invariant manifolds called slow manifolds which can be either attracting or of saddle type.In this paper, we introduce a general approach for computing two-dimensional saddle slow manifolds and their stable and unstable fast manifolds. We also develop a technique for detecting and continuing associated canard orbits, which arise from the interaction between attracting and saddle slow manifolds, and provide a mechanism for the organization of SAOs in [Formula: see text]. We first test our approach with an extended four-dimensional normal form of a folded node. Our results demonstrate that our computations give reliable approximations of slow manifolds and canard orbits of this model. Our computational approach is then utilized to investigate the role of saddle slow manifolds and associated canard orbits of the full Hodgkin-Huxley model in organizing MMOs and determining the firing rates of action potentials. For ε sufficiently large, canard orbits are arranged in pairs of twin canard orbits with the same number of SAOs. We illustrate how twin canard orbits partition the attracting slow manifold into a number of ribbons that play the role of sectors of rotations. The upshot is that we

Contaminant transport model validation: The Oak Ridge Reservation

International Nuclear Information System (INIS)

Lee, R.R.; Ketelle, R.H.

1988-09-01

In the complex geologic setting on the Oak Ridge Reservation, hydraulic conductivity is anisotropic and flow is strongly influenced by an extensive and largely discontinuous fracture network. Difficulties in describing and modeling the aquifer system prompted a study to obtain aquifer property data to be used in a groundwater flow model validation experiment. Characterization studies included the performance of an extensive suite of aquifer test within a 600-square-meter area to obtain aquifer property values to describe the flow field in detail. Following aquifer test, a groundwater tracer test was performed under ambient conditions to verify the aquifer analysis. Tracer migration data in the near-field were used in model calibration to predict tracer arrival time and concentration in the far-field. Despite the extensive aquifer testing, initial modeling inaccurately predicted tracer migration direction. Initial tracer migration rates were consistent with those predicted by the model; however, changing environmental conditions resulted in an unanticipated decay in tracer movement. Evaluation of the predictive accuracy of groundwater flow and contaminant transport models on the Oak Ridge Reservation depends on defining the resolution required, followed by field testing and model grid definition at compatible scales. The use of tracer tests, both as a characterization method and to verify model results, provides the highest level of resolution of groundwater flow characteristics. 3 refs., 4 figs

Preserved Crevasse Casts in the Whales Deep Basin, eastern Ross Sea

Science.gov (United States)

Bart, P. J.; Tulaczyk, S. M.

2017-12-01

A recent seismic stratigraphic study showed that the large bathymetric saddle in the Whales Deep Basin in eastern Ross Sea is a compound grounding zone wedge (CGZW). The basin was occupied by the paleo Bindschadler Ice Stream when grounded ice advanced to the outer continental shelf during the last glacial maximum (LGM). The CGZW is composed of at least seven overlapping GZWs. The crest of the bathymetric saddle corresponds to the grounding zone of GZW7, i.e., the seventh GZW. The north face of the saddle is essentially equivalent to the GZW7 foreset and the south side of the saddle is the GZW7 topset, i.e., the seafloor surface to which the paleo Bindschadler Ice Stream was grounded. The GZW7 topset is mantled by a series of relatively small-amplitude, but very long, ridges with low sinuosity. These ridges were previously imaged by Mosola and Anderson (2006). Here we show a larger-area multibeam survey that was acquired in 2015 during expedition NBP1502B. The larger-area multibeam survey shows that the ridges have amplitudes ranging from 2 to 11 m above grade and have an overall northeast-southwest orientation over an area of at least 500 km2 on the central and western flank of Whales Deep Basin middle continental shelf in water depths ranging from 500 to 550 m. The ridges have spacing that mostly range between 1 and 2 km. The longest ridges are observed to be 40 km. The ridges in the center of the trough have flatter tops than those in the shallower water on the flank of Houtz Bank. In our ongoing investigation of these interesting features, we hypothesize that the ridges formed below a rapidly flowing ice stream as it thinned and was decoupling from the bed towards the end of GZW7 deposition. High ice deformation rates accompanying this process caused the development of large basal crevasses or ice shelf rifts that reached the seafloor. Subglacial till was scraped and collected into lower parts of these crevasses/rifts. Chronologic data indicates that these

Flood-inundation maps for the Saddle River from Rochelle Park to Lodi, New Jersey, 2012

Science.gov (United States)

Hoppe, Heidi L.; Watson, Kara M.

2012-01-01

Digital flood-inundation maps for a 2.75-mile reach of the Saddle River from 0.2 mile upstream from the Interstate 80 bridge in Rochelle Park to 1.5 miles downstream from the U.S. Route 46 bridge in Lodi, New Jersey, were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Saddle River at Lodi, New Jersey (station 01391500). Current conditions for estimating near real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/nwis/uv?site_no=01391500. The National Weather Service (NWS) forecasts flood hydrographs at many places that are often collocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the Saddle River at Lodi, New Jersey streamgage and documented high-water marks from recent floods. The hydraulic model was then used to determine 11 water-surface profiles for flood stages at the Saddle River streamgage at 1-ft intervals referenced to the streamgage datum, North American Vertical Datum of 1988 (NAVD 88), and ranging from bankfull, 0.5 ft below NWS Action Stage, to the extent of the stage-discharge rating, which is approximately 1 ft higher than the highest recorded water level at the streamgage. Action Stage is the stage which when reached by a rising stream the NWS or a partner needs to take some type of mitigation action in

Variational Ridging in Sea Ice Models

Science.gov (United States)

Roberts, A.; Hunke, E. C.; Lipscomb, W. H.; Maslowski, W.; Kamal, S.

2017-12-01

This work presents the results of a new development to make basin-scale sea ice models aware of the shape, porosity and extent of individual ridges within the pack. We have derived an analytic solution for the Euler-Lagrange equation of individual ridges that accounts for non-conservative forces, and therefore the compressive strength of individual ridges. Because a region of the pack is simply a collection of paths of individual ridges, we are able to solve the Euler-Lagrange equation for a large-scale sea ice field also, and therefore the compressive strength of a region of the pack that explicitly accounts for the macro-porosity of ridged debris. We make a number of assumptions that have simplified the problem, such as treating sea ice as a granular material in ridges, and assuming that bending moments associated with ridging are perturbations around an isostatic state. Regardless of these simplifications, the ridge model is remarkably predictive of macro-porosity and ridge shape, and, because our equations are analytic, they do not require costly computations to solve the Euler-Lagrange equation of ridges on the large scale. The new ridge model is therefore applicable to large-scale sea ice models. We present results from this theoretical development, as well as plans to apply it to the Regional Arctic System Model and a community sea ice code. Most importantly, the new ridging model is particularly useful for pinpointing gaps in our observational record of sea ice ridges, and points to the need for improved measurements of the evolution of porosity of deformed ice in the Arctic and Antarctic. Such knowledge is not only useful for improving models, but also for improving estimates of sea ice volume derived from altimetric measurements of sea ice freeboard.

Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model

Science.gov (United States)

Yooer, Chi-Feng; Wei, Fang; Xu, Jian-Xue; Zhang, Xin-Hua

2011-03-01

We carry out numerical and theoretical investigations on the global unstable invariant set (manifold) of a saddle-node limit cycle in a leech heart interneuron model. The corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation structures. The dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories.

A computational/directional solidification method to establish saddle points on the Mg-Al-Ca liquidus

International Nuclear Information System (INIS)

Cao Hongbo; Zhang Chuan; Zhu Jun; Cao Guoping; Kou Sindo; Schmid-Fetzer, Rainer; Chang, Y. Austin

2008-01-01

We established two saddle point maxima, L + α(Mg) + C14 and L + α(Mg) + C36, on the monovariant liquidus, calculated from a previously presented thermodynamic description, by characterizing the microstructures of several directionally solidified alloys in the near-solidification front zone, the mushy zone, and the steady-state zone using optical microscopy, scanning electron microscopy and transmission electron microscopy

Using a new saddle model for echinotherapy therapy.

Directory of Open Access Journals (Sweden)

Carlos Cesar Santín Alfaro

2014-09-01

Full Text Available A descriptive study with experimental design was done, having as an objective to elaborate a new riding saddle model in the Provincial Laboratory of Technical Orthopaedics in the province of Sancti Spiritus for the Echinotherapy´s treatment in disable patients that still assisting to this kind of alternative therapy having the necessity of obtaining the frame according to the adequate characteristics and adjusting to the requirements of the qualified staff that takes care of this task taking into consideration that for the rehabilitation of these children they should be closer to the horse skin. The frame was not made with the row materials of normal chair but with the one adequate in our Laboratory. Some important characteristics were developed in this kind of therapy, and was analyzed the characteristics of the frame use give to patients, offering an immediate solution to their problems in order to solve this difficulty in our province.

Oceanic Lithosphere Magnetization: Marine Magnetic Investigations of Crustal Accretion and Tectonic Processes in Mid-Ocean Ridge Environments

Science.gov (United States)

2007-09-01

9’ 25’N on the EPR, along the northern section of the ridge bounded by the Clipperton and Siqueiros Transform Faults (TF) (Fig. 2-la). As with other...and encompasses the entire segment of the EPR from the Clipperton TF to the Siqueiros TF. The Carbotte and Macdonald [ 1992] grid was continued...al. [1996], Nicolas et al. [1996]; Kelemen et al.[1997]; Le Mee et al. [2004]), Bay of Islands ophiolite (Canada) [Swift and Johnson, 1984] and

Determination of shell correction energies at saddle point using pre-scission neutron multiplicities

International Nuclear Information System (INIS)

Golda, K.S.; Saxena, A.; Mittal, V.K.; Mahata, K.; Sugathan, P.; Jhingan, A.; Singh, V.; Sandal, R.; Goyal, S.; Gehlot, J.; Dhal, A.; Behera, B.R.; Bhowmik, R.K.; Kailas, S.

2013-01-01

Pre-scission neutron multiplicities have been measured for 12 C + 194, 198 Pt systems at matching excitation energies at near Coulomb barrier region. Statistical model analysis with a modified fission barrier and level density prescription have been carried out to fit the measured pre-scission neutron multiplicities and the available evaporation residue and fission cross sections simultaneously to constrain statistical model parameters. Simultaneous fitting of the pre-scission neutron multiplicities and cross section data requires shell correction at the saddle point

Ridge regression estimator: combining unbiased and ordinary ridge regression methods of estimation

Directory of Open Access Journals (Sweden)

Sharad Damodar Gore

2009-10-01

Full Text Available Statistical literature has several methods for coping with multicollinearity. This paper introduces a new shrinkage estimator, called modified unbiased ridge (MUR. This estimator is obtained from unbiased ridge regression (URR in the same way that ordinary ridge regression (ORR is obtained from ordinary least squares (OLS. Properties of MUR are derived. Results on its matrix mean squared error (MMSE are obtained. MUR is compared with ORR and URR in terms of MMSE. These results are illustrated with an example based on data generated by Hoerl and Kennard (1975.

Large fault fabric of the Ninetyeast Ridge implies near-spreading ridge formation

Digital Repository Service at National Institute of Oceanography (India)

Sager, W.W.; Paul, C.F.; Krishna, K.S.; Pringle, M.S.; Eisin, A.E.; Frey, F.A.; Rao, D.G.; Levchenko, O.V.

of the high ridge. At 26°S, prominent NE-SW 97 oriented lineations extend southwest from the ridge. Some appear to connect with N-S fracture 98 zone troughs east of NER, implying that the NE-SW features are fracture zone scars formed after 99 the change... to the 105 ridge (Fig. 3). This is especially true for NER south of ~4°S. Where KNOX06RR crossed a 106 gravity lineation, negative gradient features correspond to troughs whereas positive gradient 107 features result from igneous basement highs (Fig. 3...

Saddle-splay elasticity of nematic structures confined to a cylindrical capillary

International Nuclear Information System (INIS)

Kralj, S.; Zumer, S.

1995-01-01

The stability of nematic structures within a cylindrical capillary whose wall exhibits a homeotropic boundary condition is studied. The structures are obtained numerically from Euler-Lagrange equations resulting from the minimization of the Frank free energy functional. Stability diagrams are presented showing dependence on elastic properties, surface anchoring, and external transversal field strength. Emphasis is given to the effects of the saddle-splay elastic constant (K 24 ), which plays an important role in the weak anchoring regime. A new structure---the planar polar structure with two line defects---is predicted. It is shown that it is stable in a finite interval of the external field strength in the strong anchoring regime

Trends in life science grid: from computing grid to knowledge grid

Directory of Open Access Journals (Sweden)

Konagaya Akihiko

2006-12-01

Full Text Available Abstract Background Grid computing has great potential to become a standard cyberinfrastructure for life sciences which often require high-performance computing and large data handling which exceeds the computing capacity of a single institution. Results This survey reviews the latest grid technologies from the viewpoints of computing grid, data grid and knowledge grid. Computing grid technologies have been matured enough to solve high-throughput real-world life scientific problems. Data grid technologies are strong candidates for realizing "resourceome" for bioinformatics. Knowledge grids should be designed not only from sharing explicit knowledge on computers but also from community formulation for sharing tacit knowledge among a community. Conclusion Extending the concept of grid from computing grid to knowledge grid, it is possible to make use of a grid as not only sharable computing resources, but also as time and place in which people work together, create knowledge, and share knowledge and experiences in a community.

Hamiltonian flow over saddles for exploring molecular phase space structures

Science.gov (United States)

Farantos, Stavros C.

2018-03-01

Despite using potential energy surfaces, multivariable functions on molecular configuration space, to comprehend chemical dynamics for decades, the real happenings in molecules occur in phase space, in which the states of a classical dynamical system are completely determined by the coordinates and their conjugate momenta. Theoretical and numerical results are presented, employing alanine dipeptide as a model system, to support the view that geometrical structures in phase space dictate the dynamics of molecules, the fingerprints of which are traced by following the Hamiltonian flow above saddles. By properly selecting initial conditions in alanine dipeptide, we have found internally free rotor trajectories the existence of which can only be justified in a phase space perspective. This article is part of the theme issue `Modern theoretical chemistry'.

Grid interoperability: joining grid information systems

International Nuclear Information System (INIS)

Flechl, M; Field, L

2008-01-01

A grid is defined as being 'coordinated resource sharing and problem solving in dynamic, multi-institutional virtual organizations'. Over recent years a number of grid projects, many of which have a strong regional presence, have emerged to help coordinate institutions and enable grids. Today, we face a situation where a number of grid projects exist, most of which are using slightly different middleware. Grid interoperation is trying to bridge these differences and enable Virtual Organizations to access resources at the institutions independent of their grid project affiliation. Grid interoperation is usually a bilateral activity between two grid infrastructures. Recently within the Open Grid Forum, the Grid Interoperability Now (GIN) Community Group is trying to build upon these bilateral activities. The GIN group is a focal point where all the infrastructures can come together to share ideas and experiences on grid interoperation. It is hoped that each bilateral activity will bring us one step closer to the overall goal of a uniform grid landscape. A fundamental aspect of a grid is the information system, which is used to find available grid services. As different grids use different information systems, interoperation between these systems is crucial for grid interoperability. This paper describes the work carried out to overcome these differences between a number of grid projects and the experiences gained. It focuses on the different techniques used and highlights the important areas for future standardization

Corrigendum to Preconditioners for regularized saddle point problems with an application for heterogeneous Darcy flow problems

Czech Academy of Sciences Publication Activity Database

Axelsson, Owe; Blaheta, Radim

2016-01-01

Roč. 298, May 2016 (2016), s. 252-255 ISSN 0377-0427 R&D Projects: GA MŠk ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : saddle point systems * conditions of nonsingularity * spectrum of preconditioned systems Subject RIV: BA - General Mathematics Impact factor: 1.357, year: 2016 http://www.sciencedirect.com/science/article/pii/S0377042715005889

Electrical design of the BUSSARD inverter system for ASDEX upgrade saddle coils

Energy Technology Data Exchange (ETDEWEB)

Teschke, Markus, E-mail: teschke@ipp.mpg.de; Arden, Nils; Eixenberger, Horst; Rott, Michael; Suttrop, Wolfgang

2015-10-15

Highlights: • A cost effective inverter topology for AUG's 16 in-vessel saddle coils has been found. • Use of commercially available power modules is possible. • A NPC-like topology of the power stage is realized in a modular way. • The high-speed controllers and PWM engines are realized on Linux-based systems. • First experimental results of AUG plasma shots are presented. - Abstract: A set of 16 in-vessel saddle coils is installed in the ASDEX Upgrade (AUG) nuclear fusion experiment for mitigation of edge localized modes (ELM) and feedback control of resistive wall modes (RWM). The coils were driven by DC current only during previous campaigns. Now, a new inverter system “BUSSARD” (German abbr. for “Bayerischer Umrichter, schnell schaltend für AUGs rasche Drehfelder”, translated: “bavarian fast switching inverter for AUG's fast rotating fields”) is built for the experiment. A four-phase system has been assembled to simultaneously operate up to 4 groups of coils consisting of up to 4 serial-connected coils each. The maximum current is 1.3 kA with a ripple in the range of 7% and the frequency is variable between DC and approx. 100 Hz. The switching frequency is variable between approximately 3 and 10 kHz. As a first application, rotating fields are generated. The system can be enhanced in two stages to 16-phase operation with a bandwidth of 500 Hz and a 24 phase system with a bandwidth of up to 3 kHz.

Environmental baseline survey report for West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, West Pine Ridge and parcel 21D in the vicinity of the East Technology Park, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

King, David A. [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

2012-11-29

This environmental baseline survey (EBS) report documents the baseline environmental conditions of five land parcels located near the U.S. Department of Energy?s (DOE?s) East Tennessee Technology Park (ETTP), including West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, West Pine Ridge, and Parcel 21d. Preparation of this report included the detailed search of federal government records, title documents, aerial photos that may reflect prior uses, and visual inspections of the property and adjacent properties. Interviews with current employees involved in, or familiar with, operations on the real property were also conducted to identify any areas on the property where hazardous substances and petroleum products, or their derivatives, and acutely hazardous wastes may have been released or disposed. In addition, a search was made of reasonably obtainable federal, state, and local government records of each adjacent facility where there has been a release of any hazardous substance or any petroleum product or their derivatives, including aviation fuel and motor oil, and which is likely to cause or contribute to a release of any hazardous substance or any petroleum product or its derivatives, including aviation fuel or motor oil, on the real property. A radiological survey and soil/sediment sampling was conducted to assess baseline conditions of Parcel 21d that were not addressed by the soils-only no-further-investigation (NFI) reports. Groundwater sampling was also conducted to support a Parcel 21d decision. Based on available data West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, and West Pine Ridge are not impacted by site operations and are not subject to actions per the Federal Facility Agreement (FFA). This determination is supported by visual inspections, records searches and interviews, groundwater conceptual modeling, approved NFI reports, analytical data, and risk analysis results. Parcel 21d data, however, demonstrate impacts from site

Environmental baseline survey report for West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, West Pine Ridge and parcel 21D in the vicinity of the East Technology Park, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

King, David A.

2012-01-01

This environmental baseline survey (EBS) report documents the baseline environmental conditions of five land parcels located near the U.S. Department of Energy's (DOE's) East Tennessee Technology Park (ETTP), including West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, West Pine Ridge, and Parcel 21d. Preparation of this report included the detailed search of federal government records, title documents, aerial photos that may reflect prior uses, and visual inspections of the property and adjacent properties. Interviews with current employees involved in, or familiar with, operations on the real property were also conducted to identify any areas on the property where hazardous substances and petroleum products, or their derivatives, and acutely hazardous wastes may have been released or disposed. In addition, a search was made of reasonably obtainable federal, state, and local government records of each adjacent facility where there has been a release of any hazardous substance or any petroleum product or their derivatives, including aviation fuel and motor oil, and which is likely to cause or contribute to a release of any hazardous substance or any petroleum product or its derivatives, including aviation fuel or motor oil, on the real property. A radiological survey and soil/sediment sampling was conducted to assess baseline conditions of Parcel 21d that were not addressed by the soils-only no-further-investigation (NFI) reports. Groundwater sampling was also conducted to support a Parcel 21d decision. Based on available data West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, and West Pine Ridge are not impacted by site operations and are not subject to actions per the Federal Facility Agreement (FFA). This determination is supported by visual inspections, records searches and interviews, groundwater conceptual modeling, approved NFI reports, analytical data, and risk analysis results. Parcel 21d data, however, demonstrate impacts from site

A description of a wide beam saddle field ion source used for nuclear target applications

International Nuclear Information System (INIS)

Greene, J.P.; Schiel, S.L.; Thomas, G.E.

1997-01-01

A description is given of a new, wide beam saddle field sputter source used for the preparation of targets applied in nuclear physics experiments. The ion source characteristics are presented and compared with published results obtained with other sources. Deposition rates acquired utilizing this source are given for a variety of target materials encountered in nuclear target production. New applications involving target thinning and ion milling are discussed

Remedial Investigation Work Plan for Chestnut Ridge Operable Unit 1 (Chestnut Ridge Security Pits) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

1993-09-01

This Remedial Investigation (RI) Work Plan specifically addresses Chestnut Ridge Operable Unit 1, (OU1) which consists of the Chestnut Ridge Security Pits (CRSP). The CRSP are located {approximately}800 ft southeast of the central portion of the Y-12 Plant atop Chestnut Ridge, which is bounded to the northwest by Bear Creek Valley and to the southeast by Bethel Valley. Operated from 1973 to 1988, the CRSP consisted of a series of trenches used for the disposal of classified hazardous and nonhazardous waste materials. Disposal of hazardous waste materials was discontinued in December 1984, while nonhazardous waste disposal ended on November 8, 1988. An RI is being conducted at this site in response to CERCLA regulations. The overall objectives of the RI are to collect data necessary to evaluate the nature and extent of contaminants of concern (COC), support an ecological risk assessment (ERA) and a human health risk assessment (HHRA), support the evaluation of remedial alternatives, and ultimately develop a Record of Decision for the site. The purpose of this Work Plan is to outline RI activities necessary to define the nature and extent of suspected contaminants at Chestnut Ridge OU1. Potential migration pathways also will be investigated. Data collected during the RI will be used to evaluate the overall risk posed to human health and the environment by OU1.

Remedial Investigation Work Plan for Chestnut Ridge Operable Unit 1 (Chestnut Ridge Security Pits) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1993-09-01

This Remedial Investigation (RI) Work Plan specifically addresses Chestnut Ridge Operable Unit 1, (OU1) which consists of the Chestnut Ridge Security Pits (CRSP). The CRSP are located ∼800 ft southeast of the central portion of the Y-12 Plant atop Chestnut Ridge, which is bounded to the northwest by Bear Creek Valley and to the southeast by Bethel Valley. Operated from 1973 to 1988, the CRSP consisted of a series of trenches used for the disposal of classified hazardous and nonhazardous waste materials. Disposal of hazardous waste materials was discontinued in December 1984, while nonhazardous waste disposal ended on November 8, 1988. An RI is being conducted at this site in response to CERCLA regulations. The overall objectives of the RI are to collect data necessary to evaluate the nature and extent of contaminants of concern (COC), support an ecological risk assessment (ERA) and a human health risk assessment (HHRA), support the evaluation of remedial alternatives, and ultimately develop a Record of Decision for the site. The purpose of this Work Plan is to outline RI activities necessary to define the nature and extent of suspected contaminants at Chestnut Ridge OU1. Potential migration pathways also will be investigated. Data collected during the RI will be used to evaluate the overall risk posed to human health and the environment by OU1

Ridge Regression Signal Processing

Science.gov (United States)

Kuhl, Mark R.

1990-01-01

The introduction of the Global Positioning System (GPS) into the National Airspace System (NAS) necessitates the development of Receiver Autonomous Integrity Monitoring (RAIM) techniques. In order to guarantee a certain level of integrity, a thorough understanding of modern estimation techniques applied to navigational problems is required. The extended Kalman filter (EKF) is derived and analyzed under poor geometry conditions. It was found that the performance of the EKF is difficult to predict, since the EKF is designed for a Gaussian environment. A novel approach is implemented which incorporates ridge regression to explain the behavior of an EKF in the presence of dynamics under poor geometry conditions. The basic principles of ridge regression theory are presented, followed by the derivation of a linearized recursive ridge estimator. Computer simulations are performed to confirm the underlying theory and to provide a comparative analysis of the EKF and the recursive ridge estimator.

Preliminary results from the first InRidge cruise to the central Indian Ridge

Digital Repository Service at National Institute of Oceanography (India)

Mukhopadhyay, R.; Murthy, K.S.R.; Iyer, S.D.; Rao, M.M.M.; Banerjee, R.; Subrahmanyam, A.S.; Shirodkar, P.V.; Ghose, I.; Ganesan, P.; Rao, A.K.; Suribabu, A.; Ganesh, C.; Naik, G.P.

stream_size 1 stream_content_type text/plain stream_name Inter_Ridge_News_7_40.pdf.txt stream_source_info Inter_Ridge_News_7_40.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Greenland Fracture Zone-East Greenland Ridge(s) revisited: Indications of a C22-change in plate motion?

DEFF Research Database (Denmark)

Døssing, Arne; Funck, T.

2012-01-01

a reinterpretation of the Greenland Fracture Zone -East Greenland Ridge based on new and existing geophysical data. Evidence is shown for two overstepping ridge segments (Segments A and B) of which Segment A corresponds to the already known East Greenland Ridge while Segment B was not detected previously......Changes in the lithospheric stress field, causing axial rift migration and reorientation of the transform, are generally proposed as an explanation for anomalously old crust and/or major aseismic valleys in oceanic ridge-transform-ridge settings. Similarly, transform migration of the Greenland...... Fracture Zone and separation of the 200-km-long, fracture-zone-parallel continental East Greenland Ridge from the Eurasia plate is thought to be related to a major change in relative plate motions between Greenland and Eurasia during the earliest Oligocene (Chron 13 time). This study presents...

Approximate Dual Averaging Method for Multiagent Saddle-Point Problems with Stochastic Subgradients

Directory of Open Access Journals (Sweden)

Deming Yuan

2014-01-01

Full Text Available This paper considers the problem of solving the saddle-point problem over a network, which consists of multiple interacting agents. The global objective function of the problem is a combination of local convex-concave functions, each of which is only available to one agent. Our main focus is on the case where the projection steps are calculated approximately and the subgradients are corrupted by some stochastic noises. We propose an approximate version of the standard dual averaging method and show that the standard convergence rate is preserved, provided that the projection errors decrease at some appropriate rate and the noises are zero-mean and have bounded variance.

Development of a hydrological model for simulation of runoff from catchments unbounded by ridge lines

Science.gov (United States)

Vema, Vamsikrishna; Sudheer, K. P.; Chaubey, I.

2017-08-01

Watershed hydrological models are effective tools for simulating the hydrological processes in the watershed. Although there are a plethora of hydrological models, none of them can be directly applied to make water conservation decisions in irregularly bounded areas that do not confirm to topographically defined ridge lines. This study proposes a novel hydrological model that can be directly applied to any catchment, with or without ridge line boundaries. The model is based on the water balance concept, and a linear function concept to approximate the cross-boundary flow from upstream areas to the administrative catchment under consideration. The developed model is tested in 2 watersheds - Riesel Experimental Watershed and a sub-basin of Cedar Creek Watershed in Texas, USA. Hypothetical administrative catchments that did not confirm to the location of ridge lines were considered for verifying the efficacy of the model for hydrologic simulations. The linear function concept used to account the cross boundary flow was based on the hypothesis that the flow coming from outside the boundary to administrative area was proportional to the flow generated in the boundary grid cell. The model performance was satisfactory with an NSE and r2 of ≥0.80 and a PBIAS of administrative catchments of the watersheds were in good agreement with the observed hydrographs, indicating a satisfactory performance of the model in the administratively bounded areas.

Global survey of lunar wrinkle ridge formation times

Science.gov (United States)

Yue, Z.; Michael, G. G.; Di, K.; Liu, J.

2017-11-01

Wrinkle ridges are a common feature of the lunar maria and record subsequent contraction of mare infill. Constraining the timing of wrinkle ridge formation from crater counts is challenging because they have limited areal extent and it is difficult to determine whether superposed craters post-date ridge formation or have alternatively been uplifted by the deformation. Some wrinkle ridges do allow determination to be made. This is possible where a ridge shows a sufficiently steep boundary or scarp that can be identified as deforming an intersecting crater or the crater obliterates the relief of the ridge. Such boundaries constitute only a small fraction of lunar wrinkle ridge structures yet they are sufficiently numerous to enable us to obtain statistically significant crater counts over systems of structurally related wrinkle ridges. We carried out a global mapping of mare wrinkle ridges, identifying appropriate boundaries for crater identification, and mapping superposed craters. Selected groups of ridges were analyzed using the buffered crater counting method. We found that, except for the ridges in mare Tranquilitatis, the ridge groups formed with average ages between 3.5 and 3.1 Ga ago, or 100-650 Ma after the oldest observable erupted basalts where they are located. We interpret these results to suggest that local stresses from loading by basalt fill are the principal agent responsible for the formation of lunar wrinkle ridges, as others have proposed. We find a markedly longer interval before wrinkle ridge formation in Tranquilitatis which likely indicates a different mechanism of stress accumulation at this site.

Best management practices plan for the Chestnut Ridge-Filled Coal Ash Pond at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1996-05-01

The Chestnut Ridge Filled Coal Ash Pond (FCAP) Project has been established to satisfy Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements for the Chestnut Ridge Operable Unit 2. FCAP is on Chestnut Ridge, approximately 0.5 miles south of the Y-12 Plant. A 62-foot high earthen dam across Upper McCoy Branch was constructed in 1955 to create a pond to serve as a settling basin for fly and bottom ashes generated by burning coal at the Y-12 Steam Plant. Ash from the steam was mixed with water to form a slurry and then pumped to the crest of Chestnut Ridge and released through a large pipe to flow across the Sluice Channel area and into the pond. The ash slurry eventually overtopped the dam and flowed along Upper McCoy Branch to Rogers Quarry. The purpose of this document is to provide a site-specific Best Management Practices (BMP) Plan for construction associated with environmental restoration activities at the FCAP Site

Ridge interaction features of the Line Islands

Science.gov (United States)

Konter, J. G.; Koppers, A. A. P.; Storm, L. P.

2016-12-01

The sections of Pacific absolute plate motion history that precede the Hawaii-Emperor and Louisville chains are based on three chains: the Line Islands-Mid-Pacific Mountains, the Hess Rise-Shatsky Rise, and the Marshall Islands-Wake Islands (Rurutu hotspot). Although it has been clear that the Line Islands do not define a simple age progression (e.g. Schlanger et al., 1984), the apparent similarity to the Emperor Seamount geographic trend has been used to extend the overall Hawaii-Emperor track further into the past. However, we show here that plate tectonic reconstructions suggest that the Mid-Pacific Mountains (MPMs) and Line Islands (LIs) were erupted near a mid-ocean ridge, and thus these structures do not reflect absolute plate motion. Moverover, the morphology and geochemistry of the volcanoes show similarities with Pukapuka Ridge (e.g. Davis et al., 2002) and the Rano Rahi seamounts, presumed to have a shallow origin. Modern 40Ar/39Ar ages show that the LIs erupted at various times along the entire volcanic chain. The oldest structures formed within 10 Ma of plate formation. Given the short distance to the ridge system, large aseismic volcanic ridges, such as Necker Ridge and Horizon Guyot may simply reflect a connection between MPMs and the ridge, similar to the Pukapuka Ridge. The Line Islands to the south (including Karin Ridge) define short subchains of elongated seamounts that are widespread, resembling the Rano Rahi seamount field. During this time, the plate moved nearly parallel to the ridge system. The change from few large ridges to many subchains may reflect a change in absolute plate motion, similar to the Rano Rahi field. Here, significant MPMs volcanism is no longer connected to the ridge along plate motion. Similar to Pukapuka vs. Rano Rahi, the difference in direction between plate motion and the closest ridge determines whether larger ridges or smaller seamount subchains are formed. The difference between the largest structures (MPMs and LIs

Radiogenic isotopes in enriched mid-ocean ridge basalts from Explorer Ridge, northeast Pacific Ocean

Science.gov (United States)

Cousens, Brian; Weis, Dominique; Constantin, Marc; Scott, Steve

2017-09-01

Extreme gradients in topography related to variations in magma supply are observed on the Southern Explorer Ridge (SER), part of the northern Juan de Fuca ridge system. We report radiogenic isotope (Pb, Sr, Nd, Hf) and geochemical data for twenty-four basalt whole-rock and glass samples collected from the length of the SER and from Explorer Deep, a rift to the north of the SER. Lavas from the SER form a north-south geochemical gradient, dominated by E-MORB at the northern axial high, and range from T-MORB to N-MORB towards the southern deepest part of the ridge. Linear relationships between incompatible element ratios and isotopic ratios in MORB along the ridge are consistent with mixing of magmas beneath the ridge to generate the geographic gradient from E- to N-MORB. The E-MORB have high Sr and Pb, and low Nd and Hf isotopic ratios, typical of enriched mantle that includes a FOZO or HIMU isotopic component. The West Valley and Endeavour segments of the northern Juan de Fuca ridge also include this isotopic component, but the proportion of the FOZO or HIMU component is more extreme in the SER basalts. The FOZO or HIMU component may be garnet-bearing peridotite, or a garnet pyroxenite embedded in peridotite. Recycled garnet pyroxenite better explains the very shallow SER axial high, high Nb/La and La/Sm, and the ;enriched; isotopic compositions.

Near-Body Grid Adaption for Overset Grids

Science.gov (United States)

Buning, Pieter G.; Pulliam, Thomas H.

2016-01-01

A solution adaption capability for curvilinear near-body grids has been implemented in the OVERFLOW overset grid computational fluid dynamics code. The approach follows closely that used for the Cartesian off-body grids, but inserts refined grids in the computational space of original near-body grids. Refined curvilinear grids are generated using parametric cubic interpolation, with one-sided biasing based on curvature and stretching ratio of the original grid. Sensor functions, grid marking, and solution interpolation tasks are implemented in the same fashion as for off-body grids. A goal-oriented procedure, based on largest error first, is included for controlling growth rate and maximum size of the adapted grid system. The adaption process is almost entirely parallelized using MPI, resulting in a capability suitable for viscous, moving body simulations. Two- and three-dimensional examples are presented.

The MammoGrid Project Grids Architecture

CERN Document Server

McClatchey, Richard; Hauer, Tamas; Estrella, Florida; Saiz, Pablo; Rogulin, Dmitri; Buncic, Predrag; Clatchey, Richard Mc; Buncic, Predrag; Manset, David; Hauer, Tamas; Estrella, Florida; Saiz, Pablo; Rogulin, Dmitri

2003-01-01

The aim of the recently EU-funded MammoGrid project is, in the light of emerging Grid technology, to develop a European-wide database of mammograms that will be used to develop a set of important healthcare applications and investigate the potential of this Grid to support effective co-working between healthcare professionals throughout the EU. The MammoGrid consortium intends to use a Grid model to enable distributed computing that spans national borders. This Grid infrastructure will be used for deploying novel algorithms as software directly developed or enhanced within the project. Using the MammoGrid clinicians will be able to harness the use of massive amounts of medical image data to perform epidemiological studies, advanced image processing, radiographic education and ultimately, tele-diagnosis over communities of medical "virtual organisations". This is achieved through the use of Grid-compliant services [1] for managing (versions of) massively distributed files of mammograms, for handling the distri...

Tectonic and volcanic history of Rhea as inferred from studies of scarps, ridges, troughs, and other lineaments

International Nuclear Information System (INIS)

Thomas, P.G.

1988-01-01

The 13 geomorphic feature types presently defined through the analysis of landforms on Rhea are with only one exception interpretable as of tectonic or volcanic-tectonic origin. The troughs, grabens, grooves, pit chains, scarps, and other lineaments are purely extensional in nature, while the ridges are volcanic features formed in an extensional stress field; this extension was followed by a global compression era generating megaridges and megascarps. The extensional landforms seem to form a global grid pattern that is directionally similar to the theoretically projected pattern of a tidally distorted planet. 17 references

Sensor network based solar forecasting using a local vector autoregressive ridge framework

Energy Technology Data Exchange (ETDEWEB)

Xu, J. [Stony Brook Univ., NY (United States); Yoo, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Heiser, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kalb, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-04-04

The significant improvements and falling costs of photovoltaic (PV) technology make solar energy a promising resource, yet the cloud induced variability of surface solar irradiance inhibits its effective use in grid-tied PV generation. Short-term irradiance forecasting, especially on the minute scale, is critically important for grid system stability and auxiliary power source management. Compared to the trending sky imaging devices, irradiance sensors are inexpensive and easy to deploy but related forecasting methods have not been well researched. The prominent challenge of applying classic time series models on a network of irradiance sensors is to address their varying spatio-temporal correlations due to local changes in cloud conditions. We propose a local vector autoregressive framework with ridge regularization to forecast irradiance without explicitly determining the wind field or cloud movement. By using local training data, our learned forecast model is adaptive to local cloud conditions and by using regularization, we overcome the risk of overfitting from the limited training data. Our systematic experimental results showed an average of 19.7% RMSE and 20.2% MAE improvement over the benchmark Persistent Model for 1-5 minute forecasts on a comprehensive 25-day dataset.

Modularized Parallel Neutron Instrument Simulation on the TeraGrid

International Nuclear Information System (INIS)

Chen, Meili; Cobb, John W.; Hagen, Mark E.; Miller, Stephen D.; Lynch, Vickie E.

2007-01-01

In order to build a bridge between the TeraGrid (TG), a national scale cyberinfrastructure resource, and neutron science, the Neutron Science TeraGrid Gateway (NSTG) is focused on introducing productive HPC usage to the neutron science community, primarily the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). Monte Carlo simulations are used as a powerful tool for instrument design and optimization at SNS. One of the successful efforts of a collaboration team composed of NSTG HPC experts and SNS instrument scientists is the development of a software facility named PSoNI, Parallelizing Simulations of Neutron Instruments. Parallelizing the traditional serial instrument simulation on TeraGrid resources, PSoNI quickly computes full instrument simulation at sufficient statistical levels in instrument de-sign. Upon SNS successful commissioning, to the end of 2007, three out of five commissioned instruments in SNS target station will be available for initial users. Advanced instrument study, proposal feasibility evaluation, and experiment planning are on the immediate schedule of SNS, which pose further requirements such as flexibility and high runtime efficiency on fast instrument simulation. PSoNI has been redesigned to meet the new challenges and a preliminary version is developed on TeraGrid. This paper explores the motivation and goals of the new design, and the improved software structure. Further, it describes the realized new features seen from MPI parallelized McStas running high resolution design simulations of the SEQUOIA and BSS instruments at SNS. A discussion regarding future work, which is targeted to do fast simulation for automated experiment adjustment and comparing models to data in analysis, is also presented

On the many saddle points description of quantum black holes

Energy Technology Data Exchange (ETDEWEB)

Germani, Cristiano, E-mail: cristiano.germani@physik.uni-muenchen.de

2014-06-02

Considering two dimensional gravity coupled to a CFT, we show that a semiclassical black hole can be described in terms of two Liouville theories matched at the horizon. The black hole exterior corresponds to a space-like while the interior to a time-like Liouville theory. This matching automatically implies that a semiclassical black hole has an infinite entropy. The path integral description of the time-like Liouville theory (the Black Hole interior) is studied and it is found that the correlation functions of the coupled CFT-gravity system are dominated by two (complex) saddle points, even in the semiclassical limit. We argue that this system can be interpreted as two interacting Bose–Einstein condensates constructed out of two degenerate quantum states. In AdS/CFT context, the same system is mapped into two interacting strings intersecting inside a three-dimensional BTZ black hole.

Implementation of grid-connected to/from off-grid transference for micro-grid inverters

OpenAIRE

Heredero Peris, Daniel; Chillón Antón, Cristian; Pages Gimenez, Marc; Gross, Gabriel Igor; Montesinos Miracle, Daniel

2013-01-01

This paper presents the transfer of a microgrid converter from/to on-grid to/from off-grid when the converter is working in two different modes. In the first transfer presented method, the converter operates as a Current Source Inverter (CSI) when on-grid and as a Voltage Source Inverter (VSI) when off-grid. In the second transfer method, the converter is operated as a VSI both, when operated on-grid and off-grid. The two methods are implemented successfully in a real pla...

The beach ridges of India: A review

Digital Repository Service at National Institute of Oceanography (India)

Kunte, P.D.; Wagle, B.G.

, and is presented in a consolidated form. Beach ridges of the east and west coast of India are grouped in thirteen-beach ridge complexes based on their association. Review indicates that the beach ridges of India are not older than the Holocene age...

SigWin-detector: a Grid-enabled workflow for discovering enriched windows of genomic features related to DNA sequences

Directory of Open Access Journals (Sweden)

Wibisono Adianto

2008-08-01

Full Text Available Abstract Background Chromosome location is often used as a scaffold to organize genomic information in both the living cell and molecular biological research. Thus, ever-increasing amounts of data about genomic features are stored in public databases and can be readily visualized by genome browsers. To perform in silico experimentation conveniently with this genomics data, biologists need tools to process and compare datasets routinely and explore the obtained results interactively. The complexity of such experimentation requires these tools to be based on an e-Science approach, hence generic, modular, and reusable. A virtual laboratory environment with workflows, workflow management systems, and Grid computation are therefore essential. Findings Here we apply an e-Science approach to develop SigWin-detector, a workflow-based tool that can detect significantly enriched windows of (genomic features in a (DNA sequence in a fast and reproducible way. For proof-of-principle, we utilize a biological use case to detect regions of increased and decreased gene expression (RIDGEs and anti-RIDGEs in human transcriptome maps. We improved the original method for RIDGE detection by replacing the costly step of estimation by random sampling with a faster analytical formula for computing the distribution of the null hypothesis being tested and by developing a new algorithm for computing moving medians. SigWin-detector was developed using the WS-VLAM workflow management system and consists of several reusable modules that are linked together in a basic workflow. The configuration of this basic workflow can be adapted to satisfy the requirements of the specific in silico experiment. Conclusion As we show with the results from analyses in the biological use case on RIDGEs, SigWin-detector is an efficient and reusable Grid-based tool for discovering windows enriched for features of a particular type in any sequence of values. Thus, SigWin-detector provides the

SigWin-detector: a Grid-enabled workflow for discovering enriched windows of genomic features related to DNA sequences.

Science.gov (United States)

Inda, Márcia A; van Batenburg, Marinus F; Roos, Marco; Belloum, Adam S Z; Vasunin, Dmitry; Wibisono, Adianto; van Kampen, Antoine H C; Breit, Timo M

2008-08-08

Chromosome location is often used as a scaffold to organize genomic information in both the living cell and molecular biological research. Thus, ever-increasing amounts of data about genomic features are stored in public databases and can be readily visualized by genome browsers. To perform in silico experimentation conveniently with this genomics data, biologists need tools to process and compare datasets routinely and explore the obtained results interactively. The complexity of such experimentation requires these tools to be based on an e-Science approach, hence generic, modular, and reusable. A virtual laboratory environment with workflows, workflow management systems, and Grid computation are therefore essential. Here we apply an e-Science approach to develop SigWin-detector, a workflow-based tool that can detect significantly enriched windows of (genomic) features in a (DNA) sequence in a fast and reproducible way. For proof-of-principle, we utilize a biological use case to detect regions of increased and decreased gene expression (RIDGEs and anti-RIDGEs) in human transcriptome maps. We improved the original method for RIDGE detection by replacing the costly step of estimation by random sampling with a faster analytical formula for computing the distribution of the null hypothesis being tested and by developing a new algorithm for computing moving medians. SigWin-detector was developed using the WS-VLAM workflow management system and consists of several reusable modules that are linked together in a basic workflow. The configuration of this basic workflow can be adapted to satisfy the requirements of the specific in silico experiment. As we show with the results from analyses in the biological use case on RIDGEs, SigWin-detector is an efficient and reusable Grid-based tool for discovering windows enriched for features of a particular type in any sequence of values. Thus, SigWin-detector provides the proof-of-principle for the modular e-Science based concept

Novel spin transition between S = 5/2 and S = 3/2 in highly saddled iron(III) porphyrin complexes at extremely low temperatures.

Science.gov (United States)

Ohgo, Yoshiki; Chiba, Yuya; Hashizume, Daisuke; Uekusa, Hidehiro; Ozeki, Tomoji; Nakamura, Mikio

2006-05-14

A novel spin transition between S = 5/2 and S = 3/2 has been observed for the first time in five-coordinate, highly saddled iron(III) porphyrinates by EPR and SQUID measurements at extremely low temperatures.

Remedial Investigation Report on Chestnut Ridge Operable Unit 2 (Filled Coal Ash Pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 1. Main Text

International Nuclear Information System (INIS)

1994-08-01

This document is a report on the remedial investigation (RI) of Chestnut Ridge Operable Unit (OU) 2 at the Oak Ridge Y-12 Plant. Chestnut Ridge OU 2 consists of Upper McCoy Branch (UMB), the Filled Coal Ash Pond (FCAP), and the area surrounding the Sluice Channel formerly associated with coal ash disposal in the FCAP. Chestnut Ridge OU 2 is located within the U.S. Department of Energy's (DOE's) Oak Ridge Reservation in Anderson County, Tennessee, approximately 24 miles west of Knoxville. The pond is an 8.5-acre area on the southern slope of Chestnut Ridge, 0.5 mile south of the main Y-12 Plant and geographically separated from the Y-12 Plant by Chestnut Ridge. The elevation of the FCAP is ∼ 950 ft above mean sea level (msl), and it is relatively flat and largely vegetated. Two small ponds are usually present at the northeast and northwest comers of the FCAP. The Sluice Channel Area extends ∼1000 ft from the northern margin of the FCAP to the crest of Chestnut Ridge, which has an elevation of ∼1100 ft above msl. The Sluice Channel Area is largely vegetated also. McCoy Branch runs from the top of Chestnut Ridge across the FCAP into Rogers Quarry and out of the quarry where it runs a short distance into Milton Hill Lake at McCoy Embayment, termed UMB. The portion south of Rogers Quarry, within Chestnut Ridge OU 4, is termed Lower McCoy Branch. The DOE Oak Ridge Y-12 Plant disposed of coal ash from its steam plant operations as a slurry that was discharged into an ash retention impoundment; this impoundment is the FCAP. The FCAP was built in 1955 to serve as a settling basin after coal ash slurried over Chestnut Ridge from the Y-12 Plant. The FCAP was constructed by building an earthen dam across the northern tributary of McCoy Branch. The dam was designed to hold 20 years of Y-12 steam plant ash. By July 1967, ash had filled up the impoundment storage behind the dam to within 4 ft of the top

Remedial Investigation Report on Chestnut Ridge Operable Unit 2 (Filled Coal Ash Pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 1. Main Text

Energy Technology Data Exchange (ETDEWEB)

1994-08-01

This document is a report on the remedial investigation (RI) of Chestnut Ridge Operable Unit (OU) 2 at the Oak Ridge Y-12 Plant. Chestnut Ridge OU 2 consists of Upper McCoy Branch (UMB), the Filled Coal Ash Pond (FCAP), and the area surrounding the Sluice Channel formerly associated with coal ash disposal in the FCAP. Chestnut Ridge OU 2 is located within the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation in Anderson County, Tennessee, approximately 24 miles west of Knoxville. The pond is an 8.5-acre area on the southern slope of Chestnut Ridge, 0.5 mile south of the main Y-12 Plant and geographically separated from the Y-12 Plant by Chestnut Ridge. The elevation of the FCAP is {approximately} 950 ft above mean sea level (msl), and it is relatively flat and largely vegetated. Two small ponds are usually present at the northeast and northwest comers of the FCAP. The Sluice Channel Area extends {approximately}1000 ft from the northern margin of the FCAP to the crest of Chestnut Ridge, which has an elevation of {approximately}1100 ft above msl. The Sluice Channel Area is largely vegetated also. McCoy Branch runs from the top of Chestnut Ridge across the FCAP into Rogers Quarry and out of the quarry where it runs a short distance into Milton Hill Lake at McCoy Embayment, termed UMB. The portion south of Rogers Quarry, within Chestnut Ridge OU 4, is termed Lower McCoy Branch. The DOE Oak Ridge Y-12 Plant disposed of coal ash from its steam plant operations as a slurry that was discharged into an ash retention impoundment; this impoundment is the FCAP. The FCAP was built in 1955 to serve as a settling basin after coal ash slurried over Chestnut Ridge from the Y-12 Plant. The FCAP was constructed by building an earthen dam across the northern tributary of McCoy Branch. The dam was designed to hold 20 years of Y-12 steam plant ash. By July 1967, ash had filled up the impoundment storage behind the dam to within 4 ft of the top.

Preliminary Analysis of the Knipovich Ridge Segmentation - Influence of Focused Magmatism and Ridge Obliquity on an Ultraslow Spreading System

Science.gov (United States)

Okino, K.; Curewitz, D.; Asada, M.; Tamaki, K.

2002-12-01

Bathymetry, gravity and deep-tow sonar image data are used to define the segmentation of a 400 km long portion of the ultraslow-spreading Knipovich Ridge in the Norwegian-Greenland Sea, Northeast Atlantic Ocean. Discrete volcanic centers marked by large volcanic constructions and accompanying short wavelength mantle Bouguer anomaly (MBA) lows generally resemble those of the Gakkel Ridge and the easternmost Southwest Indian Ridge (SWIR). These magmatically robust segment centers are regularly spaced about 85-100 km apart along the ridge, and are characterized by accumulated hummocky terrain, high relief, off-axis seamount chains and significant MBA lows. We suggest that these eruptive centers correspond to areas of enhanced magma flux, and that their spacing reflects the geometry of underlying mantle upwelling cells. The large-scale thermal structure of the mantle primarily controls discrete and focused magmatism, and the relatively wide spacing of these segments may reflect cool mantle beneath the ridge. Segment centers along the southern Knipovich Ridge are characterized by lower relief and smaller MBA anomalies than along the northern section of the ridge. This suggests that ridge obliquity is a secondary control on ridge construction on the Knipovich Ridge, as the obliquity changes from 35° to 49° from north to south, respectively, while spreading rate and axial depth remain approximately constant. The increased obliquity may contribute to decreased effective spreading rates, lower upwelling magma velocity and melt formation, and limited horizontal dike propagation near the surface. We also identify small, magmatically weaker segments with low relief, little or no MBA anomaly, and no off axis expression. We suggest that these segments are either fed by lateral melt migration from adjacent magmatically stronger segments or represent smaller, discrete mantle upwelling centers with short-lived melt supply.

Preliminary analysis of the Knipovich Ridge segmentation: influence of focused magmatism and ridge obliquity on an ultraslow spreading system

Science.gov (United States)

Okino, Kyoko; Curewitz, Daniel; Asada, Miho; Tamaki, Kensaku; Vogt, Peter; Crane, Kathleen

2002-09-01

Bathymetry, gravity and deep-tow sonar image data are used to define the segmentation of a 400 km long portion of the ultraslow-spreading Knipovich Ridge in the Norwegian-Greenland Sea, Northeast Atlantic Ocean. Discrete volcanic centers marked by large volcanic constructions and accompanying short wavelength mantle Bouguer anomaly (MBA) lows generally resemble those of the Gakkel Ridge and the easternmost Southwest Indian Ridge. These magmatically robust segment centers are regularly spaced about 85-100 km apart along the ridge, and are characterized by accumulated hummocky terrain, high relief, off-axis seamount chains and significant MBA lows. We suggest that these eruptive centers correspond to areas of enhanced magma flux, and that their spacing reflects the geometry of underlying mantle upwelling cells. The large-scale thermal structure of the mantle primarily controls discrete and focused magmatism, and the relatively wide spacing of these segments may reflect cool mantle beneath the ridge. Segment centers along the southern Knipovich Ridge are characterized by lower relief and smaller MBA anomalies than along the northern section of the ridge. This suggests that ridge obliquity is a secondary control on ridge construction on the Knipovich Ridge, as the obliquity changes from 35° to 49° from north to south, respectively, while spreading rate and axial depth remain approximately constant. The increased obliquity may contribute to decreased effective spreading rates, lower upwelling magma velocity and melt formation, and limited horizontal dike propagation near the surface. We also identify small, magmatically weaker segments with low relief, little or no MBA anomaly, and no off-axis expression. We suggest that these segments are either fed by lateral melt migration from adjacent magmatically stronger segments or represent smaller, discrete mantle upwelling centers with short-lived melt supply.

Comprehensive integrated planning: A process for the Oak Ridge Reservation, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1998-05-01

The Oak Ridge Comprehensive Integrated Plan is intended to assist the US Department of Energy (DOE) and contractor personnel in implementing a comprehensive integrated planning process consistent with DOE Order 430.1, Life Cycle Asset Management and Oak Ridge Operations Order 430. DOE contractors are charged with developing and producing the Comprehensive Integrated Plan, which serves as a summary document, providing information from other planning efforts regarding vision statements, missions, contextual conditions, resources and facilities, decision processes, and stakeholder involvement. The Comprehensive Integrated Plan is a planning reference that identifies primary issues regarding major changes in land and facility use and serves all programs and functions on-site as well as the Oak Ridge Operations Office and DOE Headquarters. The Oak Ridge Reservation is a valuable national resource and is managed on the basis of the principles of ecosystem management and sustainable development and how mission, economic, ecological, social, and cultural factors are used to guide land- and facility-use decisions. The long-term goals of the comprehensive integrated planning process, in priority order, are to support DOE critical missions and to stimulate the economy while maintaining a quality environment

Comprehensive integrated planning: A process for the Oak Ridge Reservation, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-05-01

The Oak Ridge Comprehensive Integrated Plan is intended to assist the US Department of Energy (DOE) and contractor personnel in implementing a comprehensive integrated planning process consistent with DOE Order 430.1, Life Cycle Asset Management and Oak Ridge Operations Order 430. DOE contractors are charged with developing and producing the Comprehensive Integrated Plan, which serves as a summary document, providing information from other planning efforts regarding vision statements, missions, contextual conditions, resources and facilities, decision processes, and stakeholder involvement. The Comprehensive Integrated Plan is a planning reference that identifies primary issues regarding major changes in land and facility use and serves all programs and functions on-site as well as the Oak Ridge Operations Office and DOE Headquarters. The Oak Ridge Reservation is a valuable national resource and is managed on the basis of the principles of ecosystem management and sustainable development and how mission, economic, ecological, social, and cultural factors are used to guide land- and facility-use decisions. The long-term goals of the comprehensive integrated planning process, in priority order, are to support DOE critical missions and to stimulate the economy while maintaining a quality environment.

Smart grid

International Nuclear Information System (INIS)

Choi, Dong Bae

2001-11-01

This book describes press smart grid from basics to recent trend. It is divided into ten chapters, which deals with smart grid as green revolution in energy with introduction, history, the fields, application and needed technique for smart grid, Trend of smart grid in foreign such as a model business of smart grid in foreign, policy for smart grid in U.S.A, Trend of smart grid in domestic with international standard of smart grid and strategy and rood map, smart power grid as infrastructure of smart business with EMS development, SAS, SCADA, DAS and PQMS, smart grid for smart consumer, smart renewable like Desertec project, convergence IT with network and PLC, application of an electric car, smart electro service for realtime of electrical pricing system, arrangement of smart grid.

Classical generalized transition-state theory. Application to a collinear reaction with two saddle points

International Nuclear Information System (INIS)

Garrett, B.C.; Truhlar, D.G.; Grev, R.S.

1981-01-01

Accurate classical dynamical fixed-energy reaction probabilities and fixed-temperature rate constants are calculated for the collinear reaction H + FH on a low-barrier model potential energy surface. The calculations cover energies from 0.1 to 100 kcal/mol above threshold and temperatures of 100 to 10,000 K. The accurate results are used to test five approximate theories: conventional transition-state theory (TST), canonical variational theory (CVT), improved canonical variational theory (ICVT), microcanonical variational theory (μVT), and the unified statistical model (US). The first four of these theories involve a single dividing surface in phase space, and the US theory involves three dividing surfaces. The tests are particularly interesting because the potential energy surface has two identical saddle points. At temperatures from 100 to 2000 K, the μVt is the most accurate theory, with errors in the range 11 to 14%; for temperatures from 2000 to 10,000 K, the US theory is the most successful, with errors in the range 3 to 14%. Over the whole range, a factor of 100 in temperature, both theories have errors of 35% or less. Even TST has errors of 47% or less over the whole factor-of-100 temperature range. Although the US model should become exact at threshold for this system, it already underestimates the reaction probability by a factor of 0.64 at 0.1 kcal/mol above threshold. TST and μVT agree with each other within 12% up to an energy 13 kcal/mol above the saddle point energy. 3 figures, 2 tables

GridCom, Grid Commander: graphical interface for Grid jobs and data management

International Nuclear Information System (INIS)

Galaktionov, V.V.

2011-01-01

GridCom - the software package for maintenance of automation of access to means of distributed system Grid (jobs and data). The client part, executed in the form of Java-applets, realises the Web-interface access to Grid through standard browsers. The executive part Lexor (LCG Executor) is started by the user in UI (User Interface) machine providing performance of Grid operations

Results of the radiological survey of the Saddle River's East Bank, from State Highway 46 to the River's confluence with Lodi Brook, Lodi, New Jersey (LJ083)

International Nuclear Information System (INIS)

Foley, R.D.; Floyd, L.M.

1989-11-01

Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. MCW supplied rare earth metals and thorium compounds to the Atomic Energy Commission and various other government agencies from the late 1940s to the mid-1950s. Area residents used the sandlike waste from this thorium extraction process mixed with tea and cocoa leaves as mulch in their yards. Some of these contaminated wastes were also eroded from the site into Lodi Brook. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally 232 Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, the Saddle River's East Bank, from State Highway 46 to the River's Confluence with Lodi Brook, Lodi, New Jersey (LJ083), was conducted during 1988. Results of the survey demonstrated no radionuclide concentrations in excess of the DOE Formerly Utilized Sites Remedial Action Program criteria. The radionuclide distributions were not significantly different from normal background levels in the northern New Jersey area. 4 refs., 2 figs., 3 tabs

Oak Ridge Leadership Computing Facility (OLCF)

Data.gov (United States)

Federal Laboratory Consortium — The Oak Ridge Leadership Computing Facility (OLCF) was established at Oak Ridge National Laboratory in 2004 with the mission of standing up a supercomputer 100 times...

US Department of Energy Oak Ridge Operations Environmental Management Public Involvement Plan for the Oak Ridge Reservation

International Nuclear Information System (INIS)

1996-03-01

This document was prepared in accordance with CERCLA requirements for writing community relations plans. It includes information on how the DOE Oak Ridge Operations Office prepares and executes Environmental Management Community relations activities. It is divided into three sections: the public involvement plan, public involvement in Oak Ridge, and public involvement in 1995. Four appendices are also included: environmental management in Oak Ridge; community and regional overview; key laws, agreements, and policy; and principal contacts

Compound nucleus decay: Comparison between saddle point and scission point barriers

Energy Technology Data Exchange (ETDEWEB)

Santos, T. J.; Carlson, B. V. [Depto. de Física, Instituto Tecnológico de Aeronáutica, São José dos Campos, SP (Brazil)

2014-11-11

One of the principal characteristics of nuclear multifragmentation is the emission of complex fragments of intermediate mass. An extension of the statistical multifragmentation model has been developed, in which the process can be interpreted as the near simultaneous limit of a series of sequential binary decays. In this extension, intermediate mass fragment emissions are described by expressions almost identical to those of light particle emission. At lower temperatures, similar expressions have been shown to furnish a good description of very light intermediate mass fragment emission but not of the emission of heavier fragments, which seems to be determined by the transition density at the saddle-point rather than at the scission point. Here, we wish to compare these different formulations of intermediate fragmment emission and analyze the extent to which they remain distinguishable at high excitation energy.

InRidge program: Preliminary results from the first cruise

Digital Repository Service at National Institute of Oceanography (India)

Mukhopadhyay, R.; Murthy, K.S.R.; Iyer, S.D.; Rao, M.M.M.; Banerjee, R.; Subrahmanyam, A.S.; Shirodkar, P.V.; Ghose, I.

The first cruise under India's own Ridge research initiative, InRidge collected new data on bathymetry, free-air gravity and magnetic anomalies across the ridge axis between the Vema and Zhivago transform faults in the Central Indian Ridge...

Controlling Unknown Saddle Type Steady States of Dynamical Systems with Latency in the Feedback Loop

DEFF Research Database (Denmark)

Tamasevicius, Arunas; Bumeliene, Skaidra; Tamaseviciute, Elena

2009-01-01

We suggest an adaptive control technique for stabilizing saddle type unstable steady states of dynamical systems. The controller is composed of an unstable and a stable high-pass filters operating in parallel. The mathematical model is considered analytically and numerically. The conjoint...... controller is sufficiently robust to time latencies in the feedback loop. In addition, it is not sensitive to the damping parameters of the system and is relatively fast. Experiments have been performed using a simplified version of the electronic Young-Silva circuit imitating behavior of the Duffing...

Enabling Campus Grids with Open Science Grid Technology

International Nuclear Information System (INIS)

Weitzel, Derek; Fraser, Dan; Pordes, Ruth; Bockelman, Brian; Swanson, David

2011-01-01

The Open Science Grid is a recognized key component of the US national cyber-infrastructure enabling scientific discovery through advanced high throughput computing. The principles and techniques that underlie the Open Science Grid can also be applied to Campus Grids since many of the requirements are the same, even if the implementation technologies differ. We find five requirements for a campus grid: trust relationships, job submission, resource independence, accounting, and data management. The Holland Computing Center's campus grid at the University of Nebraska-Lincoln was designed to fulfill the requirements of a campus grid. A bridging daemon was designed to bring non-Condor clusters into a grid managed by Condor. Condor features which make it possible to bridge Condor sites into a multi-campus grid have been exploited at the Holland Computing Center as well.

Quality assurance project plan for the Chestnut Ridge Fly Ash Pond Stabilization Project at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1996-07-01

The Chestnut Ridge Fly Ash Pond Stabilization (CRFAPS) Project will stabilize a 19-m-high (62-ft-high) earthen embankment across Upper McCoy Branch situated along the southern slope of Chestnut Ridge. This task will be accomplished by raising the crest of the embankment, reinforcing the face of the embankment, removing trees from the face and top of the embankment, and repairing the emergency spillway. The primary responsibilities of the team members are: Lockheed Martin Energy Systems, Inc., (Energy Systems) will be responsible for project integration, technical support, Title 3 field support, environmental oversight, and quality assurance (QA) oversight of the project; Foster Wheeler Environmental Corporation (FWENC) will be responsible for design and home office Title 3 support; MK-Ferguson of Oak Ridge Company (MK-F) will be responsible for health and safety, construction, and procurement of construction materials. Each of the team members has a QA program approved by the US Department of Energy (DOE) Oak Ridge Operations. This project-specific QA project plan (QAPP), which is applicable to all project activities, identifies and integrates the specific QA requirements from the participant's QA programs that are necessary for this project

Assessment of grid optimisation measures for the German transmission grid using open source grid data

Science.gov (United States)

Böing, F.; Murmann, A.; Pellinger, C.; Bruckmeier, A.; Kern, T.; Mongin, T.

2018-02-01

The expansion of capacities in the German transmission grid is a necessity for further integration of renewable energy sources into the electricity sector. In this paper, the grid optimisation measures ‘Overhead Line Monitoring’, ‘Power-to-Heat’ and ‘Demand Response in the Industry’ are evaluated and compared against conventional grid expansion for the year 2030. Initially, the methodical approach of the simulation model is presented and detailed descriptions of the grid model and the used grid data, which partly originates from open-source platforms, are provided. Further, this paper explains how ‘Curtailment’ and ‘Redispatch’ can be reduced by implementing grid optimisation measures and how the depreciation of economic costs can be determined considering construction costs. The developed simulations show that the conventional grid expansion is more efficient and implies more grid relieving effects than the evaluated grid optimisation measures.

Enabling campus grids with open science grid technology

Energy Technology Data Exchange (ETDEWEB)

Weitzel, Derek [Nebraska U.; Bockelman, Brian [Nebraska U.; Swanson, David [Nebraska U.; Fraser, Dan [Argonne; Pordes, Ruth [Fermilab

2011-01-01

The Open Science Grid is a recognized key component of the US national cyber-infrastructure enabling scientific discovery through advanced high throughput computing. The principles and techniques that underlie the Open Science Grid can also be applied to Campus Grids since many of the requirements are the same, even if the implementation technologies differ. We find five requirements for a campus grid: trust relationships, job submission, resource independence, accounting, and data management. The Holland Computing Center's campus grid at the University of Nebraska-Lincoln was designed to fulfill the requirements of a campus grid. A bridging daemon was designed to bring non-Condor clusters into a grid managed by Condor. Condor features which make it possible to bridge Condor sites into a multi-campus grid have been exploited at the Holland Computing Center as well.

Saddle-fin cell transistors with oxide etch rate control by using tilted ion implantation (TIS-fin) for sub-50-nm DRAMs

International Nuclear Information System (INIS)

Yoo, Min Soo; Choi, Kang Sik; Sun, Woo Kyung

2010-01-01

As DRAM cell pitch size decreases, the need for a high performance transistor is increasing. Though saddle-fin (S-fin) transistors have superior characteristics, S-fin transistors are well known to be more sensitive to process variation. To make uniform S-fin transistors, for the first time, we developed a new fin formation method using tilted ion implantation along the wordline direction after a recess gate etch. Due to the increased etch rate of the oxide film by ion implantation damage, fins are made at the bottom channel of the recess gate after wet etching. The resulting tilt implanted saddle-fin (TIS-fin) transistor has remarkably improved characteristics, such as ∼8% subthreshold swing (SS) and a 40% drain induced barrier lowering (DIBL) decrease. Especially, the TIS-fin with a neutral dopant has a reduced threshold voltage (Vth) variation within a wafer (<100 mV), which is comparable with that of a mass-produced sphere-shaped recessed channel array transistor (SRCAT).

Petrological systematics of mid-ocean ridge basalts: Constraints on melt generation beneath ocean ridges

Science.gov (United States)

Langmuir, Charles H.; Klein, Emily M.; Plank, Terry

Mid-ocean ridge basalts (MORB) are a consequence of pressure-release melting beneath ocean ridges, and contain much information concerning melt formation, melt migration and heterogeneity within the upper mantle. MORB major element chemical systematics can be divided into global and local aspects, once they have been corrected for low pressure fractionation and interlaboratory biases. Regional average compositions for ridges unaffected by hot spots ("normal" ridges) can be used to define the global correlations among normalized Na2O, FeO, TiO2 and SiO2 contents, CaO/Al2O3 ratios, axial depth and crustal thickness. Back-arc basins show similar correlations, but are offset to lower FeO and TiO2 contents. Some hot spots, such as the Azores and Galapagos, disrupt the systematics of nearby ridges and have the opposite relationships between FeO, Na2O and depth over distances of 1000 km. Local variations in basalt chemistry from slow- and fast-spreading ridges are distinct from one another. On slow-spreading ridges, correlations among the elements cross the global vector of variability at a high angle. On the fast-spreading East Pacific Rise (EPR), correlations among the elements are distinct from both global and slow-spreading compositional vectors, and involve two components of variation. Spreading rate does not control the global correlations, but influences the standard deviations of axial depth, crustal thickness, and MgO contents of basalts. Global correlations are not found in very incompatible trace elements, even for samples far from hot spots. Moderately compatible trace elements for normal ridges, however, correlate with the major elements. Trace element systematics are significantly different for the EPR and the mid-Atlantic Ridge (MAR). Normal portions of the MAR are very depleted in REE, with little variability; hot spots cause large long wavelength variations in REE abundances. Normal EPR basalts are significantly more enriched than MAR basalts from normal

Black hole critical phenomena without black holes

Indian Academy of Sciences (India)

large values of Ф, black holes do form and for small values the scalar field ... on the near side of the ridge ultimately evolve to form black holes while those configu- ... The inset shows a bird's eye view looking down on the saddle point.

An aerial radiological survey of the Oak Ridge Reservation and surrounding area, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Maurer, R.J.

1989-09-01

An aerial radiological survey of the Oak Ridge Reservation (ORR) and surrounding area in Oak Ridge, Tennessee, was conducted from September 12--29, 1989. The purpose of the survey was to measure and document the site's terrestrial radiological environment for use in effective environmental management and emergency response planning. The aerial survey was flown at an altitude of 91 meters (300 feet) along a series of parallel lines 152 meters (500 feet) apart. The survey encompassed an area of 440 square kilometers (170 square miles) as defined by the Tennessee Valley Authority Map S-16A of the entire Oak Ridge Reservation and adjacent area. The results of the aerial survey are reported as inferred exposure rates at 1 meter above ground level (AGL) in the form of a radiation contour map. Typical background exposure rates were found to vary from 5 to 14 microroentgens per hour (μR/h). The man-made radionuclides, cobalt-60, cesium-137, and protactinium-234m (a radioisotope indicative of depleted uranium), were detected at several facilities on the site. In support of the aerial survey, ground-based exposure rate and soil sample measurements were obtained at several locations within the survey boundary. In addition to the large scale aerial survey, two special flyovers were requested by the Department of Energy. The first request was to conduct a survey of a 1-mile x 2-mile area in south Knoxville, Tennessee. The area had been used previously to store contaminated scrap metals from operations at the Oak Ridge site. The second request was to fly several passes over a 5-mile length of railroad tracks leading from the Oak Ridge Y-12 Plant, north through the city of Oak Ridge. The railroad tracks had been previously used in the transport of cesium-137

Oak Ridge Reservation environmental report for 1991

International Nuclear Information System (INIS)

Mucke, P.C.

1992-10-01

The Oak Ridge Reservation Environmental Report for 1991 is the 21st in a series that began in 1971. The report documents the annual results of a comprehensive program to estimate the impact of the US Department of Energy (DOE) Oak Ridge operations upon human health and the environment. The report is organized into ten sections that address various aspects of effluent monitoring, environmental surveillance, dose assessment, waste management, and quality assurance. A compliance summary gives a synopsis of the status of each facility relative to applicable state and federal regulations. Data are included for the following: Oak Ridge Y-12 Plant; Oak Ridge National Laboratory (ORNL); and Oak Ridge K-25 Site. Effluent monitoring and environmental surveillance programs are intended to serve as effective indicators of contaminant releases and ambient contaminant concentrations that have the potential to result in adverse impacts to human health and the environment

Derivation and Error Analysis of the Earth Magnetic Anomaly Grid at 2 arc min Resolution Version 3 (EMAG2v3)

Science.gov (United States)

Meyer, B.; Chulliat, A.; Saltus, R.

2017-12-01

The Earth Magnetic Anomaly Grid at 2 arc min resolution version 3, EMAG2v3, combines marine and airborne trackline observations, satellite data, and magnetic observatory data to map the location, intensity, and extent of lithospheric magnetic anomalies. EMAG2v3 includes over 50 million new data points added to NCEI's Geophysical Database System (GEODAS) in recent years. The new grid relies only on observed data, and does not utilize a priori geologic structure or ocean-age information. Comparing this grid to other global magnetic anomaly compilations (e.g., EMAG2 and WDMAM), we can see that the inclusion of a priori ocean-age patterns forces an artificial linear pattern to the grid; the data-only approach allows for greater complexity in representing the evolution along oceanic spreading ridges and continental margins. EMAG2v3 also makes use of the satellite-derived lithospheric field model MF7 in order to accurately represent anomalies with wavelengths greater than 300 km and to create smooth grid merging boundaries. The heterogeneous distribution of errors in the observations used in compiling the EMAG2v3 was explored, and is reported in the final distributed grid. This grid is delivered at both 4 km continuous altitude above WGS84, as well as at sea level for all oceanic and coastal regions.

GridCom, Grid Commander: graphical interface for Grid jobs and data management; GridCom, Grid Commander: graficheskij interfejs dlya raboty s zadachami i dannymi v gride

Energy Technology Data Exchange (ETDEWEB)

Galaktionov, V V

2011-07-01

GridCom - the software package for maintenance of automation of access to means of distributed system Grid (jobs and data). The client part, executed in the form of Java-applets, realises the Web-interface access to Grid through standard browsers. The executive part Lexor (LCG Executor) is started by the user in UI (User Interface) machine providing performance of Grid operations

Progress in Grid Generation: From Chimera to DRAGON Grids

Science.gov (United States)

Liou, Meng-Sing; Kao, Kai-Hsiung

1994-01-01

Hybrid grids, composed of structured and unstructured grids, combines the best features of both. The chimera method is a major stepstone toward a hybrid grid from which the present approach is evolved. The chimera grid composes a set of overlapped structured grids which are independently generated and body-fitted, yielding a high quality grid readily accessible for efficient solution schemes. The chimera method has been shown to be efficient to generate a grid about complex geometries and has been demonstrated to deliver accurate aerodynamic prediction of complex flows. While its geometrical flexibility is attractive, interpolation of data in the overlapped regions - which in today's practice in 3D is done in a nonconservative fashion, is not. In the present paper we propose a hybrid grid scheme that maximizes the advantages of the chimera scheme and adapts the strengths of the unstructured grid while at the same time keeps its weaknesses minimal. Like the chimera method, we first divide up the physical domain by a set of structured body-fitted grids which are separately generated and overlaid throughout a complex configuration. To eliminate any pure data manipulation which does not necessarily follow governing equations, we use non-structured grids only to directly replace the region of the arbitrarily overlapped grids. This new adaptation to the chimera thinking is coined the DRAGON grid. The nonstructured grid region sandwiched between the structured grids is limited in size, resulting in only a small increase in memory and computational effort. The DRAGON method has three important advantages: (1) preserving strengths of the chimera grid; (2) eliminating difficulties sometimes encountered in the chimera scheme, such as the orphan points and bad quality of interpolation stencils; and (3) making grid communication in a fully conservative and consistent manner insofar as the governing equations are concerned. To demonstrate its use, the governing equations are

Dynamical instability produces transform faults at mid-ocean ridges.

Science.gov (United States)

Gerya, Taras

2010-08-27

Transform faults at mid-ocean ridges--one of the most striking, yet enigmatic features of terrestrial plate tectonics--are considered to be the inherited product of preexisting fault structures. Ridge offsets along these faults therefore should remain constant with time. Here, numerical models suggest that transform faults are actively developing and result from dynamical instability of constructive plate boundaries, irrespective of previous structure. Boundary instability from asymmetric plate growth can spontaneously start in alternate directions along successive ridge sections; the resultant curved ridges become transform faults within a few million years. Fracture-related rheological weakening stabilizes ridge-parallel detachment faults. Offsets along the transform faults change continuously with time by asymmetric plate growth and discontinuously by ridge jumps.

Wrinkle Ridges and Young Fresh Crater

Science.gov (United States)

2002-01-01

(Released 10 May 2002) The Science Wrinkle ridges are a very common landform on Mars, Mercury, Venus, and the Moon. These ridges are linear to arcuate asymmetric topographic highs commonly found on smooth plains. The origin of wrinkle ridges is not certain and two leading hypotheses have been put forth by scientists over the past 40 years. The volcanic model calls for the extrusion of high viscosity lavas along linear conduits. This thick lava accumulated over these conduits and formed the ridges. The other model is tectonic and advocates that the ridges are formed by compressional faulting and folding. Today's THEMIS image is of the ridged plains of Lunae Planum located between Kasei Valles and Valles Marineris in the northern hemisphere of the planet. Wrinkle ridges are found mostly along the eastern side of the image. The broadest wrinkle ridges in this image are up to 2 km wide. A 3 km diameter young fresh crater is located near the bottom of the image. The crater's ejecta blanket is also clearly seen surrounding the sharp well-defined crater rim. These features are indicative of a very young crater that has not been subjected to erosional processes. The Story The great thing about the solar system is that planets are both alike and different. They're all foreign enough to be mysterious and intriguing, and yet familiar enough to be seen as planetary 'cousins.' By comparing them, we can learn a lot about how planets form and then evolve geologically over time. Crinkled over smooth plains, the long, wavy raised landforms seen here are called 'wrinkle ridges,' and they've been found on Mars, Mercury, Venus, and the Moon - that is, on rocky bodies that are a part of our inner solar system. We know from this observation that planets (and large-enough moons) follow similar processes. What we don't know for sure is HOW these processes work. Scientists have been trying to understand how wrinkle ridges form for 40 years, and they still haven't reached a conclusion. That

Technical Note: Rapid prototyping of 3D grid arrays for image guided therapy quality assurance

International Nuclear Information System (INIS)

Kittle, David; Holshouser, Barbara; Slater, James M.; Guenther, Bob D.; Pitsianis, Nikos P.; Pearlstein, Robert D.

2008-01-01

Three dimensional grid phantoms offer a number of advantages for measuring imaging related spatial inaccuracies for image guided surgery and radiotherapy. The authors examined the use of rapid prototyping technology for directly fabricating 3D grid phantoms from CAD drawings. We tested three different fabrication process materials, photopolymer jet with acrylic resin (PJ/AR), selective laser sintering with polyamide (SLS/P), and fused deposition modeling with acrylonitrile butadiene styrene (FDM/ABS). The test objects consisted of rectangular arrays of control points formed by the intersections of posts and struts (2 mm rectangular cross section) and spaced 8 mm apart in the x, y, and z directions. The PJ/AR phantom expanded after immersion in water which resulted in permanent warping of the structure. The surface of the FDM/ABS grid exhibited a regular pattern of depressions and ridges from the extrusion process. SLS/P showed the best combination of build accuracy, surface finish, and stability. Based on these findings, a grid phantom for assessing machine-dependent and frame-induced MR spatial distortions was fabricated to be used for quality assurance in stereotactic neurosurgical and radiotherapy procedures. The spatial uniformity of the SLS/P grid control point array was determined by CT imaging (0.6x0.6x0.625 mm 3 resolution) and found suitable for the application, with over 97.5% of the control points located within 0.3 mm of the position specified in CAD drawing and none of the points off by more than 0.4 mm. Rapid prototyping is a flexible and cost effective alternative for development of customized grid phantoms for medical physics quality assurance.

Oak Ridge Reservation environmental report for 1989

International Nuclear Information System (INIS)

Jacobs, V.A.; Wilson, A.R.

1990-10-01

This two-volume report, the Oak Ridge Reservation Environmental Report for 1989, is the nineteenth in an annual series that began in 1971. It reports the results of a comprehensive, year-round program to monitor the impact of operations at the three major US Department of Energy (DOE) production and research installations in Oak Ridge on the immediate areas' and surrounding region's groundwater and surface waters, soil, air quality, vegetation and wildlife, and through these multiple and varied pathways, the resident human population. Information is presented for the environmental monitoring Quality Assurance (QA) Program, audits and reviews, waste management activities, land special environmental studies. Data are included for the Oak Ridge Y-12 Plant, Oak Ridge National Laboratory (ORNL), and Oak Ridge Gaseous Diffusion Plant (ORGDP). Volume 1 presents narratives, summaries, and conclusions based on environmental monitoring at the three DOE installations and in the surrounding environs during calendar year (CY) 1989. Volume 1 is intended to be a ''stand-alone'' report about the Oak Ridge Reservation (ORR) for the reader who does not want an in-depth review of 1989 data. Volume 2 presents the detailed data from which these conclusions have been drawn and should be used in conjunction with Volume 1

Oak Ridge Reservation environmental report for 1989

Energy Technology Data Exchange (ETDEWEB)

Jacobs, V.A.; Wilson, A.R. (eds.)

1990-10-01

This two-volume report, the Oak Ridge Reservation Environmental Report for 1989, is the nineteenth in an annual series that began in 1971. It reports the results of a comprehensive, year-round program to monitor the impact of operations at the three major US Department of Energy (DOE) production and research installations in Oak Ridge on the immediate areas' and surrounding region's groundwater and surface waters, soil, air quality, vegetation and wildlife, and through these multiple and varied pathways, the resident human population. Information is presented for the environmental monitoring Quality Assurance (QA) Program, audits and reviews, waste management activities, land special environmental studies. Data are included for the Oak Ridge Y-12 Plant, Oak Ridge National Laboratory (ORNL), and Oak Ridge Gaseous Diffusion Plant (ORGDP). Volume 1 presents narratives, summaries, and conclusions based on environmental monitoring at the three DOE installations and in the surrounding environs during calendar year (CY) 1989. Volume 1 is intended to be a stand-alone'' report about the Oak Ridge Reservation (ORR) for the reader who does not want an in-depth review of 1989 data. Volume 2 presents the detailed data from which these conclusions have been drawn and should be used in conjunction with Volume 1.

MICROARRAY IMAGE GRIDDING USING GRID LINE REFINEMENT TECHNIQUE

Directory of Open Access Journals (Sweden)

V.G. Biju

2015-05-01

Full Text Available An important stage in microarray image analysis is gridding. Microarray image gridding is done to locate sub arrays in a microarray image and find co-ordinates of spots within each sub array. For accurate identification of spots, most of the proposed gridding methods require human intervention. In this paper a fully automatic gridding method which enhances spot intensity in the preprocessing step as per a histogram based threshold method is used. The gridding step finds co-ordinates of spots from horizontal and vertical profile of the image. To correct errors due to the grid line placement, a grid line refinement technique is proposed. The algorithm is applied on different image databases and results are compared based on spot detection accuracy and time. An average spot detection accuracy of 95.06% depicts the proposed method’s flexibility and accuracy in finding the spot co-ordinates for different database images.

Alveolar ridge rehabilitation to increase full denture retention and stability

Directory of Open Access Journals (Sweden)

Mefina Kuntjoro

2010-12-01

Full Text Available Background: Atrophic mandibular alveolar ridge generally complicates prostetic restoration expecially full denture. Low residual alveolar ridge and basal seat can cause unstable denture, permanent ulcer, pain, neuralgia, and mastication difficulty. Pre-proshetic surgery is needed to improve denture retention and stability. Augmentation is a major surgery to increase vertical height of the atrophic mandible while vestibuloplasty is aimed to increase the denture bearing area. Purpose: The augmentation and vestibuloplasty was aimed to provide stability and retentive denture atrophic mandibular alveolar ridge. Case: A 65 years old woman patient complained about uncomfortable denture. Clinical evaluate showed flat ridge in the anterior mandible, flabby tissue and candidiasis, while residual ridge height was classified into class IV. Case management: Augmentation using autograph was conducted as the mandible vertical height is less than 15 mm. Autograph was used to achieve better bone quantity and quality. Separated alveolar ridge was conducted from left to right canine region and was elevated 0.5 mm from the previous position to get new ridge in the anterior region. The separated alveolar ridge was fixated by using T-plate and ligature wire. Three months after augmentation fixation appliances was removed vestibuloplasty was performed to increase denture bearing area that can make a stable and retentive denture. Conclusion: Augmentation and vestibuloplasty can improve flat ridge to become prominent.Latar belakang: Ridge mandibula yang atrofi pada umumnya mempersulit pembuatan restorasi prostetik terutama gigi tiruan lengkap (GTL. Residual alveolar ridge dan basal seat yang rendah menyebabkan gigi tiruan menjadi tidak stabil, menimbulkan ulser permanen, nyeri, neuralgia, dan kesulitan mengunyah. Tujuan: Augmentasi dan vestibuloplasti pada ridge mandibula yang atrofi dilakukan untuk menciptakan gigi tiruan yang stabil dan retentive. Kasus: Pasien wanita

Grid3: An Application Grid Laboratory for Science

CERN Multimedia

CERN. Geneva

2004-01-01

level services required by the participating experiments. The deployed infrastructure has been operating since November 2003 with 27 sites, a peak of 2800 processors, work loads from 10 different applications exceeding 1300 simultaneous jobs, and data transfers among sites of greater than 2 TB/day. The Grid3 infrastructure was deployed from grid level services provided by groups and applications within the collaboration. The services were organized into four distinct "grid level services" including: Grid3 Packaging, Monitoring and Information systems, User Authentication and the iGOC Grid Operatio...

Ridge and Furrow Fields

DEFF Research Database (Denmark)

Møller, Per Grau

2016-01-01

Ridge and furrow is a specific way of ploughing which makes fields of systematic ridges and furrows like a rubbing washboard. They are part of an overall openfield system, but the focus in this paper is on the functionality of the fields. There are many indications that agro-technological reasons...... systems and the establishment of basic structures like villages (with churches) and townships and states (in northern Europe). The fields can be considered as a resilient structure lasting for 800 years, along with the same basic physical structures in society....

Grid-connected to/from off-grid transference for micro-grid inverters

OpenAIRE

Heredero Peris, Daniel; Chillón Antón, Cristian; Pages Gimenez, Marc; Gross, Gabriel Igor; Montesinos Miracle, Daniel

2013-01-01

This paper compares two methods for controlling the on-line transference from connected to stand-alone mode and vice versa in converters for micro-grids. The first proposes a method where the converter changes from CSI (Current Source Inverter) in grid-connected mode to VSI (Voltage Source Inverter) in off-grid. In the second method, the inverter always works as a non-ideal voltage source, acting as VSI, using AC droop control strategy.

The GridSite Web/Grid security system

International Nuclear Information System (INIS)

McNab, Andrew; Li Yibiao

2010-01-01

We present an overview of the current status of the GridSite toolkit, describing the security model for interactive and programmatic uses introduced in the last year. We discuss our experiences of implementing these internal changes and how they and previous rounds of improvements have been prompted by requirements from users and wider security trends in Grids (such as CSRF). Finally, we explain how these have improved the user experience of GridSite-based websites, and wider implications for portals and similar web/grid sites.

Process Research and Development of Antibodies as Countermeasures for C. botulinum

Science.gov (United States)

2009-02-01

ProteinA –Sepharose Fast Flow resin (Amersham Biosciences). Alternatively, culture supernatant was di- rectly loaded onto the rProtein A–Sepharose Fast Flow...interest; however the stationary point was a saddle point, so we move on the ridge in the direction to get the maximum response. The points on the...10 Ridge of steepest ascent of the reduced model for getting maximum antibody production with independent vari- ables X1, X2, X3. X4 and X5 are kept

Current Grid operation and future role of the Grid

Science.gov (United States)

Smirnova, O.

2012-12-01

Grid-like technologies and approaches became an integral part of HEP experiments. Some other scientific communities also use similar technologies for data-intensive computations. The distinct feature of Grid computing is the ability to federate heterogeneous resources of different ownership into a seamless infrastructure, accessible via a single log-on. Like other infrastructures of similar nature, Grid functioning requires not only technologically sound basis, but also reliable operation procedures, monitoring and accounting. The two aspects, technological and operational, are closely related: weaker is the technology, more burden is on operations, and other way around. As of today, Grid technologies are still evolving: at CERN alone, every LHC experiment uses an own Grid-like system. This inevitably creates a heavy load on operations. Infrastructure maintenance, monitoring and incident response are done on several levels, from local system administrators to large international organisations, involving massive human effort worldwide. The necessity to commit substantial resources is one of the obstacles faced by smaller research communities when moving computing to the Grid. Moreover, most current Grid solutions were developed under significant influence of HEP use cases, and thus need additional effort to adapt them to other applications. Reluctance of many non-HEP researchers to use Grid negatively affects the outlook for national Grid organisations, which strive to provide multi-science services. We started from the situation where Grid organisations were fused with HEP laboratories and national HEP research programmes; we hope to move towards the world where Grid will ultimately reach the status of generic public computing and storage service provider and permanent national and international Grid infrastructures will be established. How far will we be able to advance along this path, depends on us. If no standardisation and convergence efforts will take place

Current Grid operation and future role of the Grid

International Nuclear Information System (INIS)

Smirnova, O

2012-01-01

Grid-like technologies and approaches became an integral part of HEP experiments. Some other scientific communities also use similar technologies for data-intensive computations. The distinct feature of Grid computing is the ability to federate heterogeneous resources of different ownership into a seamless infrastructure, accessible via a single log-on. Like other infrastructures of similar nature, Grid functioning requires not only technologically sound basis, but also reliable operation procedures, monitoring and accounting. The two aspects, technological and operational, are closely related: weaker is the technology, more burden is on operations, and other way around. As of today, Grid technologies are still evolving: at CERN alone, every LHC experiment uses an own Grid-like system. This inevitably creates a heavy load on operations. Infrastructure maintenance, monitoring and incident response are done on several levels, from local system administrators to large international organisations, involving massive human effort worldwide. The necessity to commit substantial resources is one of the obstacles faced by smaller research communities when moving computing to the Grid. Moreover, most current Grid solutions were developed under significant influence of HEP use cases, and thus need additional effort to adapt them to other applications. Reluctance of many non-HEP researchers to use Grid negatively affects the outlook for national Grid organisations, which strive to provide multi-science services. We started from the situation where Grid organisations were fused with HEP laboratories and national HEP research programmes; we hope to move towards the world where Grid will ultimately reach the status of generic public computing and storage service provider and permanent national and international Grid infrastructures will be established. How far will we be able to advance along this path, depends on us. If no standardisation and convergence efforts will take place

Geology along the Blue Ridge Parkway in Virginia

Science.gov (United States)

Carter, Mark W.; Southworth, C. Scott; Tollo, Richard P.; Merschat, Arthur J.; Wagner, Sara; Lazor, Ava; Aleinikoff, John N.

2017-01-01

Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the boundary of the central and southern Appalachians, rocks along the parkway showcase the transition from the para-autochthonous Blue Ridge anticlinorium of northern and central Virginia to the allochthonous eastern Blue Ridge in southern Virginia. From mile post (MP) 0 near Waynesboro, Virginia, to ~MP 124 at Roanoke, the parkway crosses the unconformable to faulted boundary between Mesoproterozoic basement in the core of the Blue Ridge anticlinorium and Neoproterozoic to Cambrian metasedimentary and metavolcanic cover rocks on the western limb of the structure. Mesoproterozoic basement rocks comprise two groups based on SHRIMP U-Pb zircon geochronology: Group I rocks (1.2-1.14 Ga) are strongly foliated orthogneisses, and Group II rocks (1.08-1.00 Ga) are granitoids that mostly lack obvious Mesoproterozoic deformational features.Neoproterozoic to Cambrian cover rocks on the west limb of the anticlinorium include the Swift Run and Catoctin Formations, and constituent formations of the Chilhowee Group. These rocks unconformably overlie basement, or abut basement along steep reverse faults. Rocks of the Chilhowee Group are juxtaposed against Cambrian rocks of the Valley and Ridge province along southeast- and northwest-dipping, high-angle reverse faults. South of the James River (MP 64), Chilhowee Group and basement rocks occupy the hanging wall of the nearly flat-lying Blue Ridge thrust fault and associated splays.South of the Red Valley high-strain zone (MP 144.5), the parkway crosses into the wholly allochthonous eastern Blue Ridge, comprising metasedimentary and meta-igneous rocks assigned to the Wills Ridge, Ashe, and Alligator

Environmental records from temperate glacier ice on Nevado Coropuna saddle, southern Peru

Directory of Open Access Journals (Sweden)

J. Herreros

2009-10-01

Full Text Available We investigated past climate variability and the zonal short and long-range transport of air masses in tropical South America using chemical, isotopic and palynological signals from a 42 m-long ice core recovered in 2003 from the saddle of the Nevado Coropuna, southern Peru (72°39´ W; 15°32´ S; 6080 m a.s.l.. We found that precipitation at this site depends mainly on the easterly circulation of air masses originated from the tropical Atlantic Ocean. Nevertheless, sporadic Pacific air masses arrivals, and strong cold waves coming from southern South America reach this altitude site. In spite of post-depositional effects, we were able to identify two strong ENSO (El Niño-Southern Oscillation event signatures (1982–1983 and 1992 and the eruptive activity of the nearby Sabancaya volcano (1994.

Glacial modulation of mid-ocean ridge magmatism and anomalous Pacific Antarctic Ridge volcanism during Termination II

Science.gov (United States)

Asimow, P. D.; Lewis, M.; Lund, D. C.; Seeley, E.; McCart, S.; Mudahy, A.

2017-12-01

Glacially-driven sea level rise and fall may modulate submarine volcanism by superposing pressure changes on the tectonic decompression that causes melt production in the mantle below mid-ocean ridges. A number of recent studies have considered whether this effect is recorded in the periodicity of ridge flank bathymetry (Tolstoy, 2015; Crowley et al., 2015) but interpretation of the bathymetric data remains controversial (Goff, 2016; Olive et al., 2016). We have pursued an independent approach using hydrothermal metals in well-dated near-ridge sediment cores. Along the full length of the East Pacific Rise, in areas of the ocean with widely variable biologic productivity, there are large and consistent rises in Fe, Mn, and As concentrations during the last two glacial terminations. We interpret these cores as records of excess hydrothermal flux due to delayed delivery to the axis of excess melt generated by the preceding falls in sea level. Here we discuss the potentially related discovery, in a core near the Pacific Antarctic Ridge (PAR), of a 10 cm thick layer of basaltic ash shards up to 250 mm in size, coincident with the penultimate deglaciation (Termination II). Although the site was 8 km off-axis at the time, the glasses have major element, volatile, and trace element composition consistent with more evolved members of the axial MORB suite from the nearby ridge axis. Their morphologies are typical of pyroclastic deposits created by explosive submarine volcanism (Clague et al., 2009). We propose that a period of low magmatic flux following a sea-level rise caused cooling of crustal magmatic systems, more advanced fractionation in the axial magma chamber, and increases in viscosity and volatile concentration. We hypothesize subsequent arrival of high magmatic flux during Termination II then reactivated the system and triggered an unusually vigorous series of explosive eruptions along this segment of the PAR. Ash layers recording large eruptions such as this one

OGC and Grid Interoperability in enviroGRIDS Project

Science.gov (United States)

Gorgan, Dorian; Rodila, Denisa; Bacu, Victor; Giuliani, Gregory; Ray, Nicolas

2010-05-01

EnviroGRIDS (Black Sea Catchment Observation and Assessment System supporting Sustainable Development) [1] is a 4-years FP7 Project aiming to address the subjects of ecologically unsustainable development and inadequate resource management. The project develops a Spatial Data Infrastructure of the Black Sea Catchment region. The geospatial technologies offer very specialized functionality for Earth Science oriented applications as well as the Grid oriented technology that is able to support distributed and parallel processing. One challenge of the enviroGRIDS project is the interoperability between geospatial and Grid infrastructures by providing the basic and the extended features of the both technologies. The geospatial interoperability technology has been promoted as a way of dealing with large volumes of geospatial data in distributed environments through the development of interoperable Web service specifications proposed by the Open Geospatial Consortium (OGC), with applications spread across multiple fields but especially in Earth observation research. Due to the huge volumes of data available in the geospatial domain and the additional introduced issues (data management, secure data transfer, data distribution and data computation), the need for an infrastructure capable to manage all those problems becomes an important aspect. The Grid promotes and facilitates the secure interoperations of geospatial heterogeneous distributed data within a distributed environment, the creation and management of large distributed computational jobs and assures a security level for communication and transfer of messages based on certificates. This presentation analysis and discusses the most significant use cases for enabling the OGC Web services interoperability with the Grid environment and focuses on the description and implementation of the most promising one. In these use cases we give a special attention to issues such as: the relations between computational grid and

Ridge Orientations of the Ridge-Forming Unit, Sinus Meridiani, Mars-A Fluvial Explanation

Science.gov (United States)

Wilkinson, M. Justin; Herridge, A.

2013-01-01

Imagery and MOLA data were used in an analysis of the ridge-forming rock unit (RFU) exposed in Sinus Meridiani (SM). This unit shows parallels at different scales with fluvial sedimentary bodies. We propose the terrestrial megafan as the prime analog for the RFU, and likely for other members of the layered units. Megafans are partial cones of fluvial sediment, with radii up to hundreds of km. Although recent reviews of hypotheses for the RFU units exclude fluvial hypotheses [1], inverted ridges in the deserts of Oman have been suggested as putative analogs for some ridges [2], apparently without appreciating The wider context in which these ridges have formed is a series of megafans [3], a relatively unappreciated geomorphic feature. It has been argued that these units conform to the megafan model at the regional, subregional and local scales [4]. At the regional scale suites of terrestrial megafans are known to cover large areas at the foot of uplands on all continents - a close parallel with the setting of the Meridiani sediments at the foot of the southern uplands of Mars, with its incised fluvial systems leading down the regional NW slope [2, 3] towards the sedimentary units. At the subregional scale the layering and internal discontinuities of the Meridiani rocks are consistent, inter alia, with stacked fluvial units [4]. Although poorly recognized as such, the prime geomorphic environment in which stream channel networks cover large areas, without intervening hillslopes, is the megafan [see e.g. 4]. Single megafans can reach 200,000 km2 [5]. Megafans thus supply an analog for areas where channel-like ridges (as a palimpsest of a prior landscape) cover the intercrater plains of Meridiani [6]. At the local, or river-reach scale, the numerous sinuous features of the RFU are suggestive of fluvial channels. Cross-cutting relationships, a common feature of channels on terrestrial megafans, are ubiquitous. Desert megafans show cemented paleo-channels as inverted

Aerodynamic roughness length related to non-aggregated tillage ridges

Directory of Open Access Journals (Sweden)

M. Kardous

2005-11-01

Full Text Available Wind erosion in agricultural soils is dependent, in part, on the aerodynamic roughness length (z₀ produced by tillage ridges. Although previous studies have related z₀ to ridge characteristics (ridge height (RH and spacing (RS, these relationships have not been tested for tillage ridges observed in the North African agricultural fields. In these regions, due to climate and soil conditions, small plowing tools are largely used. Most of these tools produce non-aggregated and closely-spaced small ridges. Thus, experiments were conducted in a 7-m long wind tunnel to measure z₀ for 11 ridge types covering the range of geometric characteristics frequently observed in south Tunisia. Experimental results suggest that RH²/RS is the first order parameter controlling z₀. A strong relationship between z₀ and RH²/RS is proposed for a wide range of ridge characteristics.

caGrid 1.0: a Grid enterprise architecture for cancer research.

Science.gov (United States)

Oster, Scott; Langella, Stephen; Hastings, Shannon; Ervin, David; Madduri, Ravi; Kurc, Tahsin; Siebenlist, Frank; Covitz, Peter; Shanbhag, Krishnakant; Foster, Ian; Saltz, Joel

2007-10-11

caGrid is the core Grid architecture of the NCI-sponsored cancer Biomedical Informatics Grid (caBIG) program. The current release, caGrid version 1.0, is developed as the production Grid software infrastructure of caBIG. Based on feedback from adopters of the previous version (caGrid 0.5), it has been significantly enhanced with new features and improvements to existing components. This paper presents an overview of caGrid 1.0, its main components, and enhancements over caGrid 0.5.

Rate of deformation in the Pasco Basin during the Miocene as determined by distribution of Columbia River basalt flows

International Nuclear Information System (INIS)

Reidel, S.P.; Ledgerwood, R.K.; Myers, C.W.; Jones, M.G.; Landon, R.D.

1980-03-01

Detailed mapping of over 8000 square kilometers and logs from 20 core holes were used to determine the distribution and thickness of basalt flows and interbeds in the Pasco Basin. The data indicate the high-MgO Grande Ronde Basalt and Wanapum Basalt thicken from the northeast to the southwest. Deformation began in late Frenchman Springs time in the Saddle Mountains along a northwest-southeast trend and in Roza time along an east-west trend. By late Wanapum time, basalt flows were more restricted on the east side. Saddle Mountains Basalt flows spread out in the basin from narrow channels to the east. The Umatilla Member entered from the southeast and is confined to the south-central basin, while the Wilbur Creek, Asotin, Esquatzel, Pomona, and Elephant Mountain Members entered from the east and northeast. The distribution of these members is controlled by flow volume, boundaries of other flows, and developing ridges. The Wilbur Creek, Asotin, and Esquatzel flows exited from the basin in a channel along the northern margin of the Umatilla flow, while the Pomona and Elephant Mountain flows exited between Umtanum Ridge and Wallula Gap. The thickness of sedimentary interbeds and basalt flows indicated subsidence and/or uplift began in post-Grande Ronde time (14.5 million years before present) and continued through Saddle Mountains time (10.5 million years before present). Maximum subsidence occurred 40 kilometers (24 miles) north of Richland, Washington with an approximate rate of 25 meters (81 feet) per million years during the eruption of the basalt. Maximum uplift along the developing ridges was 70 meters (230 feet) per million years

Calendar year 1995 groundwater quality report for the Chestnut Ridge Hydrogeological Regime, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. 1995 Groundwater quality data and calculated rate of contaminant migration

International Nuclear Information System (INIS)

1996-02-01

This annual groundwater quality report (GWQR) contains groundwater quality data obtained during the 1995 calendar year (CY) at several hazardous and nonhazardous waste management facilities associated with the U.S. Department of Energy (DOE) Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. These sites are located south of the Y-12 Plant in the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime), which is one of three regimes defined for the purposes of groundwater quality monitoring at the Y-12 Plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability (HSEA) Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The U.S. Environmental Protection Agency (EPA) identification number for the Y-12 Plant is TN

A Case Report of Ridge Augmentation using Onlay Interpositional Graft: An Approach to Improve Prosthetic Prognosis of a Deficit Ridge

Directory of Open Access Journals (Sweden)

Devanand Shetty

2014-01-01

Full Text Available Background: Periodontal therapy has developed beyond the scope of the treatment of periodontal pathoses. Periodontal plastic surgery consists of the reconstructive procedures designed to enhance the both function and esthetics. Deficient ridges pose a severe problem to the restorative dentist in restoring the natural form, function and esthetics of the prosthesis replacing the natural dentition. Depending upon the severity, location of these defects and the prosthetic option chosen, hard and soft tissue ridge augmentation or non-surgical approach or a combination may help to address them. The present clinical report describes a soft tissue ridge augmentation of a localized ridge defect in maxillary aesthetic region using onlay interpositional graft followed by fixed partial denture.

ENVIRONMENTAL BASELINE SURVEY REPORT FOR WEST BLACK OAK RIDGE, EAST BLACK OAK RIDGE, MCKINNEY RIDGE, WEST PINE RIDGE, AND PARCEL 21D IN THE VICINITY OF THE EAST TENNESSEE TECHNOLOGY PARK, OAK RIDGE, TENNESSEE

Energy Technology Data Exchange (ETDEWEB)

David A. King

2012-11-29

This environmental baseline survey (EBS) report documents the baseline environmental conditions of five land parcels located near the U.S. Department of Energy’s (DOE’s) East Tennessee Technology Park (ETTP), including West Black Oak Ridge, East Black Oak Ridge, McKinney Ridge, West Pine Ridge, and Parcel 21d. The goal is to obtain all media no-further-investigation (NFI) determinations for the subject parcels considering existing soils. To augment the existing soils-only NFI determinations, samples of groundwater, surface water, soil, and sediment were collected to support all media NFI decisions. The only updates presented here are those that were made after the original issuance of the NFI documents. In the subject parcel where the soils NFI determination was not completed for approval (Parcel 21d), the full process has been performed to address the soils as well. Preparation of this report included the detailed search of federal government records, title documents, aerial photos that may reflect prior uses, and visual inspections of the property and adjacent properties. Interviews with current employees involved in, or familiar with, operations on the real property were also conducted to identify any areas on the property where hazardous substances and petroleum products, or their derivatives, and acutely hazardous wastes may have been released or disposed. In addition, a search was made of reasonably obtainable federal, state, and local government records of each adjacent facility where there has been a release of any hazardous substance or any petroleum product or their derivatives, including aviation fuel and motor oil, and which is likely to cause or contribute to a release of any hazardous substance or any petroleum product or its derivatives, including aviation fuel or motor oil, on the real property. A radiological survey and soil/sediment sampling was conducted to assess baseline conditions of Parcel 21d that were not addressed by the soils-only NFI

Mid-Ocean Ridge Melt Supply and Glacial Cycles: A 3D EPR Study of Crustal Thickness, Layer 2A, and Bathymetry

Science.gov (United States)

Boulahanis, B.; Aghaei, O.; Carbotte, S. M.; Huybers, P. J.; Langmuir, C. H.; Nedimovic, M. R.; Carton, H. D.; Canales, J. P.

2017-12-01

Recent studies suggest that eustatic sea level fluctuations induced by glacial cycles in the Pleistocene may influence mantle-melting and volcanic eruptions at mid-ocean ridges (MOR), with models predicting variation in oceanic crustal thickness linked to sea level change. Previous analyses of seafloor bathymetry as a proxy for crustal thickness show significant spectral energy at frequencies linked to Milankovitch cycles of 1/23, 1/41, and 1/100 ky-1, however the effects of faulting in seafloor relief and its spectral characteristics are difficult to separate from climatic signals. Here we investigate the hypothesis of climate driven periodicity in MOR magmatism through spectral analysis, time series comparisons, and statistical characterization of bathymetry data, seismic layer 2A thickness (as a proxy for extrusive volcanism), and seafloor-to-Moho thickness (as a proxy for total magma production). We utilize information from a three-dimensional multichannel seismic study of the East Pacific Rise and its flanks from 9°36`N to 9°57`N. We compare these datasets to the paleoclimate "LR04" benthic δ18O stack. The seismic dataset covers 770 km2 and provides resolution of Moho for 92% of the imaged region. This is the only existing high-resolution 3-D image across oceanic crust, making it ideal for assessing the possibility that glacial cycles modulate magma supply at fast spreading MORs. The layer 2A grid extends 9 km (170 ky) from the ridge axis, while Moho imaging extends to a maximum of 16 km (310 ky). Initial results from the East Pacific Rise show a relationship between sea level and both crustal thickness and sea floor depth, consistent with the hypothesis that magma supply to MORs may be modulated by glacial cycles. Analysis of crustal thickness and bathymetry data reveals spectral peaks at Milankovitch frequencies of 1/100 ky-1 and 1/41 ky-1 where datasets extend sufficiently far from the ridge. The layer 2A grid does not extend sufficiently far from the

A deep structural ridge beneath central India

Science.gov (United States)

Agrawal, P. K.; Thakur, N. K.; Negi, J. G.

A joint-inversion of magnetic satellite (MAGSAT) and free air gravity data has been conducted to quantitatively investigate the cause for Bouguer gravity anomaly over Central Indian plateaus and possible fold consequences beside Himalayan zone in the Indian sub-continent due to collision between Indian and Eurasian plates. The appropriate inversion with 40 km crustal depth model has delineated after discriminating high density and magnetisation models, for the first time, about 1500 km long hidden ridge structure trending NW-SE. The structure is parallel to Himalayan fold axis and the Indian Ocean ridge in the Arabian Sea. A quantitative relief model across a representative anomaly profile confirms the ridge structure with its highest point nearly 6 km higher than the surrounding crustal level in peninsular India. The ridge structure finds visible support from the astro-geoidal contours.

Computing closest saddle node bifurcations in a radial system via conic programming

Energy Technology Data Exchange (ETDEWEB)

Jabr, R.A. [Electrical, Computer and Communication Engineering Department, Notre Dame University, P.O. Box 72, Zouk Mikhael, Zouk Mosbeh (Lebanon); Pal, B.C. [Department of Electrical and Electronic Engineering, Imperial College London, SW7 2BT (United Kingdom)

2009-07-15

This paper considers the problem of computing the loading limits in a radial system which are (i) locally closest to current operating load powers and (ii) at which saddle node bifurcation occurs. The procedure is based on a known technique which requires iterating between two computational steps until convergence. In essence, step 1 produces a vector normal to the real and/or reactive load solution space boundary, whereas step 2 computes the bifurcation point along that vector. The paper shows that each of the above computational steps can be formulated as a second-order cone program for which polynomial time interior-point methods and efficient implementations exist. The proposed conic programming approach is used to compute the closest bifurcation points and the corresponding worst case load power margins of eleven different distribution systems. The approach is validated graphically and the existence of multiple load power margins is investigated. (author)

Integrability and Linearizability of the Lotka-Volterra System with a Saddle Point with Rational Hyperbolicity Ratio

Science.gov (United States)

Gravel, Simon; Thibault, Pierre

In this paper, we consider normalizability, integrability and linearizability properties of the Lotka-Volterra system in the neighborhood of a singular point with eigenvalues 1 and - λ. The results are obtained by generalizing and expanding two methods already known: the power expansion of the first integral or of the linearizing transformation and the transformation of the saddle into a node. With these methods we find conditions that are valid for λ∈ R+ or λ∈ Q. These conditions will allow us to find all the integrable and linearizable systems for λ= {p}/{2} and {2}/{p} with p∈ N+.

Conjugate gradient filtering of instantaneous normal modes, saddles on the energy landscape, and diffusion in liquids.

Science.gov (United States)

Chowdhary, J; Keyes, T

2002-02-01

Instantaneous normal modes (INM's) are calculated during a conjugate-gradient (CG) descent of the potential energy landscape, starting from an equilibrium configuration of a liquid or crystal. A small number (approximately equal to 4) of CG steps removes all the Im-omega modes in the crystal and leaves the liquid with diffusive Im-omega which accurately represent the self-diffusion constant D. Conjugate gradient filtering appears to be a promising method, applicable to any system, of obtaining diffusive modes and facilitating INM theory of D. The relation of the CG-step dependent INM quantities to the landscape and its saddles is discussed.

Gridded Species Distribution, Version 1: Global Amphibians Presence Grids

Data.gov (United States)

National Aeronautics and Space Administration — The Global Amphibians Presence Grids of the Gridded Species Distribution, Version 1 is a reclassified version of the original grids of amphibian species distribution...

Metallogenesis along the Indian Ocean Ridge System

Digital Repository Service at National Institute of Oceanography (India)

Banerjee, R.; Ray, Dwijesh

including India. Among these studies majority were concentrated around the Central Indian Ridge and the Southwest Indian Ridge areas, while a few observations were made around the rest of the areas in the IORS. The findings of these studies are discussed...

Chimera Grid Tools

Science.gov (United States)

Chan, William M.; Rogers, Stuart E.; Nash, Steven M.; Buning, Pieter G.; Meakin, Robert

2005-01-01

Chimera Grid Tools (CGT) is a software package for performing computational fluid dynamics (CFD) analysis utilizing the Chimera-overset-grid method. For modeling flows with viscosity about geometrically complex bodies in relative motion, the Chimera-overset-grid method is among the most computationally cost-effective methods for obtaining accurate aerodynamic results. CGT contains a large collection of tools for generating overset grids, preparing inputs for computer programs that solve equations of flow on the grids, and post-processing of flow-solution data. The tools in CGT include grid editing tools, surface-grid-generation tools, volume-grid-generation tools, utility scripts, configuration scripts, and tools for post-processing (including generation of animated images of flows and calculating forces and moments exerted on affected bodies). One of the tools, denoted OVERGRID, is a graphical user interface (GUI) that serves to visualize the grids and flow solutions and provides central access to many other tools. The GUI facilitates the generation of grids for a new flow-field configuration. Scripts that follow the grid generation process can then be constructed to mostly automate grid generation for similar configurations. CGT is designed for use in conjunction with a computer-aided-design program that provides the geometry description of the bodies, and a flow-solver program.

Ridge Waveguide Structures in Magnesium-Doped Lithium Niobate

Science.gov (United States)

Himmer, Phillip; Battle, Philip; Suckow, William; Switzer, Greg

2011-01-01

This work proposes to establish the feasibility of fabricating isolated ridge waveguides in 5% MgO:LN. Ridge waveguides in MgO:LN will significantly improve power handling and conversion efficiency, increase photonic component integration, and be well suited to spacebased applications. The key innovation in this effort is to combine recently available large, high-photorefractive-damage-threshold, z-cut 5% MgO:LN with novel ridge fabrication techniques to achieve high-optical power, low-cost, high-volume manufacturing of frequency conversion structures. The proposed ridge waveguide structure should maintain the characteristics of the periodically poled bulk substrate, allowing for the efficient frequency conversion typical of waveguides and the high optical damage threshold and long lifetimes typical of the 5% doped bulk substrate. The low cost and large area of 5% MgO:LN wafers, and the improved performance of the proposed ridge waveguide structure, will enhance existing measurement capabilities as well as reduce the resources required to achieve high-performance specifications. The purpose of the ridge waveguides in MgO:LN is to provide platform technology that will improve optical power handling and conversion efficiency compared to existing waveguide technology. The proposed ridge waveguide is produced using standard microfabrication techniques. The approach is enabled by recent advances in inductively coupled plasma etchers and chemical mechanical planarization techniques. In conjunction with wafer bonding, this fabrication methodology can be used to create arbitrarily shaped waveguides allowing complex optical circuits to be engineered in nonlinear optical materials such as magnesium doped lithium niobate. Researchers here have identified NLO (nonlinear optical) ridge waveguide structures as having suitable value to be the leading frequency conversion structures. Its value is based on having the low-cost fabrication necessary to satisfy the challenging pricing

Some improved classification-based ridge parameter of Hoerl and ...

African Journals Online (AJOL)

Some improved classification-based ridge parameter of Hoerl and Kennard estimation techniques. ... This assumption is often violated and Ridge Regression estimator introduced by [2]has been identified to be more efficient than ordinary least square (OLS) in handling it. However, it requires a ridge parameter, K, of which ...

Grid: From EGEE to EGI and from INFN-Grid to IGI

International Nuclear Information System (INIS)

Giselli, A.; Mazzuccato, M.

2009-01-01

In the last fifteen years the approach of the computational Grid has changed the way to use computing resources. Grid computing has raised interest worldwide in academia, industry, and government with fast development cycles. Great efforts, huge funding and resources have been made available through national, regional and international initiatives aiming at providing Grid infrastructures, Grid core technologies, Grid middle ware and Grid applications. The Grid software layers reflect the architecture of the services developed so far by the most important European and international projects. In this paper Grid e-Infrastructure story is given, detailing European, Italian and international projects such as EGEE, INFN-Grid and NAREGI. In addition the sustainability issue in the long-term perspective is described providing plans by European and Italian communities with EGI and IGI.

From the grid to the smart grid, topologically

Science.gov (United States)

Pagani, Giuliano Andrea; Aiello, Marco

2016-05-01

In its more visionary acceptation, the smart grid is a model of energy management in which the users are engaged in producing energy as well as consuming it, while having information systems fully aware of the energy demand-response of the network and of dynamically varying prices. A natural question is then: to make the smart grid a reality will the distribution grid have to be upgraded? We assume a positive answer to the question and we consider the lower layers of medium and low voltage to be the most affected by the change. In our previous work, we analyzed samples of the Dutch distribution grid (Pagani and Aiello, 2011) and we considered possible evolutions of these using synthetic topologies modeled after studies of complex systems in other technological domains (Pagani and Aiello, 2014). In this paper, we take an extra important step by defining a methodology for evolving any existing physical power grid to a good smart grid model, thus laying the foundations for a decision support system for utilities and governmental organizations. In doing so, we consider several possible evolution strategies and apply them to the Dutch distribution grid. We show how increasing connectivity is beneficial in realizing more efficient and reliable networks. Our proposal is topological in nature, enhanced with economic considerations of the costs of such evolutions in terms of cabling expenses and economic benefits of evolving the grid.

Grid Generation Techniques Utilizing the Volume Grid Manipulator

Science.gov (United States)

Alter, Stephen J.

1998-01-01

This paper presents grid generation techniques available in the Volume Grid Manipulation (VGM) code. The VGM code is designed to manipulate existing line, surface and volume grids to improve the quality of the data. It embodies an easy to read rich language of commands that enables such alterations as topology changes, grid adaption and smoothing. Additionally, the VGM code can be used to construct simplified straight lines, splines, and conic sections which are common curves used in the generation and manipulation of points, lines, surfaces and volumes (i.e., grid data). These simple geometric curves are essential in the construction of domain discretizations for computational fluid dynamic simulations. By comparison to previously established methods of generating these curves interactively, the VGM code provides control of slope continuity and grid point-to-point stretchings as well as quick changes in the controlling parameters. The VGM code offers the capability to couple the generation of these geometries with an extensive manipulation methodology in a scripting language. The scripting language allows parametric studies of a vehicle geometry to be efficiently performed to evaluate favorable trends in the design process. As examples of the powerful capabilities of the VGM code, a wake flow field domain will be appended to an existing X33 Venturestar volume grid; negative volumes resulting from grid expansions to enable flow field capture on a simple geometry, will be corrected; and geometrical changes to a vehicle component of the X33 Venturestar will be shown.

The Grid

CERN Document Server

Klotz, Wolf-Dieter

2005-01-01

Grid technology is widely emerging. Grid computing, most simply stated, is distributed computing taken to the next evolutionary level. The goal is to create the illusion of a simple, robust yet large and powerful self managing virtual computer out of a large collection of connected heterogeneous systems sharing various combinations of resources. This talk will give a short history how, out of lessons learned from the Internet, the vision of Grids was born. Then the extensible anatomy of a Grid architecture will be discussed. The talk will end by presenting a selection of major Grid projects in Europe and US and if time permits a short on-line demonstration.

Design assessment for the Bethel Valley FFA Upgrades at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1995-09-01

This report describes the proposed upgrades to Building 3025 and the Evaporator Area at Oak Ridge National Laboratory. Design assessments, specifications and drawings are provided. Building 3025 is a general purpose research facility utilized by the Materials and Ceramics Division to conduct research on irradiated materials. The Evaporator Area, building 2531, serves as the collection point for all low-level liquid wastes generated at the Oak Ridge National Laboratory

Parallel grid population

Science.gov (United States)

Wald, Ingo; Ize, Santiago

2015-07-28

Parallel population of a grid with a plurality of objects using a plurality of processors. One example embodiment is a method for parallel population of a grid with a plurality of objects using a plurality of processors. The method includes a first act of dividing a grid into n distinct grid portions, where n is the number of processors available for populating the grid. The method also includes acts of dividing a plurality of objects into n distinct sets of objects, assigning a distinct set of objects to each processor such that each processor determines by which distinct grid portion(s) each object in its distinct set of objects is at least partially bounded, and assigning a distinct grid portion to each processor such that each processor populates its distinct grid portion with any objects that were previously determined to be at least partially bounded by its distinct grid portion.

THz-waves channeling in a monolithic saddle-coil for Dynamic Nuclear Polarization enhanced NMR

Science.gov (United States)

Macor, A.; de Rijk, E.; Annino, G.; Alberti, S.; Ansermet, J.-Ph.

2011-10-01

A saddle coil manufactured by electric discharge machining (EDM) from a solid piece of copper has recently been realized at EPFL for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance experiments (DNP-NMR) at 9.4 T. The corresponding electromagnetic behavior of radio-frequency (400 MHz) and THz (263 GHz) waves were studied by numerical simulation in various measurement configurations. Moreover, we present an experimental method by which the results of the THz-wave numerical modeling are validated. On the basis of the good agreement between numerical and experimental results, we conducted by numerical simulation a systematic analysis on the influence of the coil geometry and of the sample properties on the THz-wave field, which is crucial in view of the optimization of DNP-NMR in solids.

The MicroGrid: A Scientific Tool for Modeling Computational Grids

Directory of Open Access Journals (Sweden)

H.J. Song

2000-01-01

Full Text Available The complexity and dynamic nature of the Internet (and the emerging Computational Grid demand that middleware and applications adapt to the changes in configuration and availability of resources. However, to the best of our knowledge there are no simulation tools which support systematic exploration of dynamic Grid software (or Grid resource behavior. We describe our vision and initial efforts to build tools to meet these needs. Our MicroGrid simulation tools enable Globus applications to be run in arbitrary virtual grid resource environments, enabling broad experimentation. We describe the design of these tools, and their validation on micro-benchmarks, the NAS parallel benchmarks, and an entire Grid application. These validation experiments show that the MicroGrid can match actual experiments within a few percent (2% to 4%.

Geomorphological investigation of multiphase glacitectonic composite ridge systems in Svalbard

Science.gov (United States)

Lovell, Harold; Benn, Douglas I.; Lukas, Sven; Spagnolo, Matteo; Cook, Simon J.; Swift, Darrel A.; Clark, Chris D.; Yde, Jacob C.; Watts, Tom

2018-01-01

Some surge-type glaciers on the High-Arctic archipelago of Svalbard have large glacitectonic composite ridge systems at their terrestrial margins. These have formed by rapid glacier advance into proglacial sediments during the active surge phase, creating multicrested moraine complexes. Such complexes can be formed during single surge advances or multiple surges to successively less-extensive positions. The few existing studies of composite ridge systems have largely relied on detailed information on internal structure and sedimentology to reconstruct their formation and links to surge processes. However, natural exposures of internal structure are commonly unavailable, and the creation of artificial exposures is often problematic in fragile Arctic environments. To compensate for these issues, we investigate the potential for reconstructing composite ridge system formation based on geomorphological evidence alone, focusing on clear morphostratigraphic relationships between ridges within the moraine complex and relict meltwater channels/outwash fans. Based on mapping at the margins of Finsterwalderbreen (in Van Keulenfjorden) and Grønfjordbreen (in Grønfjorden), we show that relict meltwater channels that breach outer parts of the composite ridge systems are in most cases truncated upstream within the ridge complex by an inner pushed ridge or ridges at their ice-proximal extents. Our interpretation of this relationship is that the entire composite ridge system is unlikely to have formed during the same glacier advance but is instead the product of multiple advances to successively less-extensive positions, whereby younger ridges are emplaced on the ice-proximal side of older ridges. This indicates that the Finsterwalderbreen composite ridge system has been formed by multiple separate advances, consistent with the cyclicity of surges. Being able to identify the frequency and magnitude of former surges is important as it provides insight into the past behaviour of

Oak Ridge reservation land-use plan

Energy Technology Data Exchange (ETDEWEB)

Bibb, W. R.; Hardin, T. H.; Hawkins, C. C.; Johnson, W. A.; Peitzsch, F. C.; Scott, T. H.; Theisen, M. R.; Tuck, S. C.

1980-03-01

This study establishes a basis for long-range land-use planning to accommodate both present and projected DOE program requirements in Oak Ridge. In addition to technological requirements, this land-use plan incorporates in-depth ecological concepts that recognize multiple uses of land as a viable option. Neither environmental research nor technological operations need to be mutually exclusive in all instances. Unique biological areas, as well as rare and endangered species, need to be protected, and human and environmental health and safety must be maintained. The plan is based on the concept that the primary use of DOE land resources must be to implement the overall DOE mission in Oak Ridge. This document, along with the base map and overlay maps, provides a reasonably detailed description of the DOE Oak Ridge land resources and of the current and potential uses of the land. A description of the land characteristics, including geomorphology, agricultural productivity and soils, water courses, vegetation, and terrestrial and aquatic animal habitats, is presented to serve as a resource document. Essentially all DOE land in the Oak Ridge area is being fully used for ongoing DOE programs or has been set aside as protected areas.

Calendar year 1993 groundwater quality report for the Chestnut Ridge Hydrogeologic Regime, Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-02-01

This annual groundwater report contains groundwater quality data obtained during the 1993 calendar year (CY) at several hazardous and non-hazardous waste-management facilities associated with the US Department of Energy (DOE) Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. These sites are located south of the Y-12 Plant in the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime), which is one of three regimes defined for the purposes of groundwater quality monitoring at the Y-12 Plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The annual groundwater report for the Chestnut Ridge Regime is completed in two-parts; Part 1 (this report) containing the groundwater quality data and Part 2 containing a detailed evaluation of the data. The primary purpose of this report is to serve as a reference for the groundwater quality data obtained each year under the lead of the Y-12 Plant GWPP. However, because it contains information needed to comply with Resource Conservation and Recovery Act (RCRA) interim status assessment monitoring and reporting requirements, this report is submitted to the Tennessee Department of Health and Environment (TDEC) by the RCRA reporting deadline

Modelling noise propagation using Grid Resources. Progress within GDI-Grid

Science.gov (United States)

Kiehle, Christian; Mayer, Christian; Padberg, Alexander; Stapelfeld, Hartmut

2010-05-01

Modelling noise propagation using Grid Resources. Progress within GDI-Grid. GDI-Grid (english: SDI-Grid) is a research project funded by the German Ministry for Science and Education (BMBF). It aims at bridging the gaps between OGC Web Services (OWS) and Grid infrastructures and identifying the potential of utilizing the superior storage capacities and computational power of grid infrastructures for geospatial applications while keeping the well-known service interfaces specified by the OGC. The project considers all major OGC webservice interfaces for Web Mapping (WMS), Feature access (Web Feature Service), Coverage access (Web Coverage Service) and processing (Web Processing Service). The major challenge within GDI-Grid is the harmonization of diverging standards as defined by standardization bodies for Grid computing and spatial information exchange. The project started in 2007 and will continue until June 2010. The concept for the gridification of OWS developed by lat/lon GmbH and the Department of Geography of the University of Bonn is applied to three real-world scenarios in order to check its practicability: a flood simulation, a scenario for emergency routing and a noise propagation simulation. The latter scenario is addressed by the Stapelfeldt Ingenieurgesellschaft mbH located in Dortmund adapting their LimA software to utilize grid resources. Noise mapping of e.g. traffic noise in urban agglomerates and along major trunk roads is a reoccurring demand of the EU Noise Directive. Input data requires road net and traffic, terrain, buildings and noise protection screens as well as population distribution. Noise impact levels are generally calculated in 10 m grid and along relevant building facades. For each receiver position sources within a typical range of 2000 m are split down into small segments, depending on local geometry. For each of the segments propagation analysis includes diffraction effects caused by all obstacles on the path of sound propagation

Oak Ridge low-level waste disposal facility designs

International Nuclear Information System (INIS)

Van Hoesen, S.D.; Jones, L.S.

1991-01-01

The strategic planning process that culuminates in the identification, selection, construction, and ultimate operation of treatment, storage, and disposal facilities for all types of low-level waste (LLW) generated on the Oak Ridge Reservation (ORR) was conducted under the Low-Level Waste Disposal Development and Demonstration (LLWDDD) Program. This program considered management of various concentrations of short half-life radionuclides generated principally at Oak Ridge National Laboratory (ORNL) and long half-life radionuclides (principally uranium) generated at the Oak Ridge Y-12 Plant and the Oak Ridge K-25 Plant. The LLWDDD Program is still ongoing and involves four phases: (1) alternative identification and evaluation, (2) technology demonstration, (3) limited operational implementation, and (4) full operational implementation. This document provides a discussion of these phases

A saddle-point for data verification and materials accountancy to control nuclear material

International Nuclear Information System (INIS)

Beedgen, R.

1983-01-01

Materials accountancy is one of the main elements in international safeguards to determine whether or not nuclear material has been diverted in nuclear plants. The inspector makes independent measurements to verify the plant-operator's data before closing the materials balance with the operator's data. All inspection statements are in principle probability statements because of random errors in measuring the material and verification on a random sampling basis. Statistical test procedures help the inspector to decide under this uncertainty. In this paper a statistical test procedure representing a saddle-point is presented that leads to the highest guaranteed detection probability taking all concealing strategies into account. There are arguments favoring a separate statistical evaluation of data verification and materials accountancy. Following these considerations, a bivariate test procedure is explained that evaluates verification and accountancy separately. (orig.) [de

Smart grid security

Energy Technology Data Exchange (ETDEWEB)

Cuellar, Jorge (ed.) [Siemens AG, Muenchen (Germany). Corporate Technology

2013-11-01

The engineering, deployment and security of the future smart grid will be an enormous project requiring the consensus of many stakeholders with different views on the security and privacy requirements, not to mention methods and solutions. The fragmentation of research agendas and proposed approaches or solutions for securing the future smart grid becomes apparent observing the results from different projects, standards, committees, etc, in different countries. The different approaches and views of the papers in this collection also witness this fragmentation. This book contains the following papers: 1. IT Security Architecture Approaches for Smart Metering and Smart Grid. 2. Smart Grid Information Exchange - Securing the Smart Grid from the Ground. 3. A Tool Set for the Evaluation of Security and Reliability in Smart Grids. 4. A Holistic View of Security and Privacy Issues in Smart Grids. 5. Hardware Security for Device Authentication in the Smart Grid. 6. Maintaining Privacy in Data Rich Demand Response Applications. 7. Data Protection in a Cloud-Enabled Smart Grid. 8. Formal Analysis of a Privacy-Preserving Billing Protocol. 9. Privacy in Smart Metering Ecosystems. 10. Energy rate at home Leveraging ZigBee to Enable Smart Grid in Residential Environment.

Lateral ridge split and immediate implant placement in moderately resorbed alveolar ridges: How much is the added width?

Directory of Open Access Journals (Sweden)

Amin Rahpeyma

2013-01-01

Full Text Available Background: Lateral ridge split technique is a way to solve the problem of the width in narrow ridges with adequate height. Simultaneous insertion of dental implants will considerably reduce the edentulism time. Materials and Methods: Twenty-five patients who were managed with ridge splitting technique were enrolled. Thirty-eight locations in both jaws with near equal distribution in quadrants received 82 dental fixtures. Beta Tricalcium phosphate (Cerasorb® was used as biomaterial to fill the intercortical space. Submerged implants were used and 3 months later healing caps were placed. Direct bone measurements before and after split were done with a Collis. Patients were clinically re-evaluated at least 6 months after implant loading. All the data were analyzed by Statistical Package for Social Sciences (SPSS software version 11.5 (SPSS Inc, Chicago Illinois, USA. Frequency of edentulous spaces and pre/post operative bone width was analyzed. Paired t-test was used for statistical analysis. Difference was considered significant if P value was less than 0.05. Results: Mean value for presplit width was 3.2 ± 0.34 mm while post-split mean width was 5.57 ± 0.49 mm. Mean gain in crest ridge after ridge splitting was 2 ± 0.3 mm. Statistical analysis showed significant differences in width before and after operation ((P < 0.05. All implants (n = 82 survived and were in full function at follow up (at least 6 months after implant loading. Conclusion: Ridge splitting technique in both jaws showed the predictable outcomes, if appropriate cases selected and special attention paid to details; then the waiting time between surgery and beginning of prosthodontic treatment can be reduced to 3 month.

Remedial investigation work plan for Chestnut Ridge Operable Unit 4 (Rogers Quarry/Lower McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

1993-09-01

The Oak Ridge Y-12 Plant includes - 800 acres near the northeast comer of the reservation and adjacent to the city of Oak Ridge (Fig. 1-1). The plant is a manufacturing and developmental engineering facility that produced components for various nuclear weapons systems and provides engineering support to other Energy Systems facilities. More than 200 contaminated sites have been identified at the Y-12 Plant that resulted from past waste management practices. Many of the sites have operable units (OUs) based on priority and on investigative and remediation requirements. This Remedial Investigation RI work plan specifically addresses Chestnut Ridge OU 4. Chestnut Ridge OU 4 consists of Rogers Quarry and Lower McCoy Branch (MCB). Rogers Quarry, which is also known as Old Rogers Quarry or Bethel Valley Quarry was used for quarrying from the late 1940s or early 1950s until about 1960. Since that time, the quarry has been used for disposal of coal ash and materials from Y-12 production operations, including classified materials. Disposal of coal ash ended in July 1993. An RI is being conducted at this site in response to CERCLA regulations. The overall objectives of the RI are to collect data necessary to evaluate the nature and extent of contaminants of concern, support an Ecological Risk Assessment and a Human Health Risk Assessment, support the evaluation of remedial alternatives, and ultimately develop a Record of Decision for the site. The purpose of this work plan is to outline RI activities necessary to define the nature and extent of suspected contaminants at Chestnut Ridge OU 4. Potential migration pathways also will be investigated. Data collected during the RI will be used to evaluate the risk posed to human health and the environment by OU 4.

Synchronization in single-phase grid-connected photovoltaic systems under grid faults

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede

2012-01-01

The highly increasing penetration of single-phase photovoltaic (PV) systems pushes the grid requirements related to the integration of PV power systems to be updated. These upcoming regulations are expected to direct the grid-connected renewable generators to support the grid operation and stabil......The highly increasing penetration of single-phase photovoltaic (PV) systems pushes the grid requirements related to the integration of PV power systems to be updated. These upcoming regulations are expected to direct the grid-connected renewable generators to support the grid operation...

Peri-anal surgery under saddle block anaesthesia comparing three different doses of hyperbaric 0.75% bupivacaine

International Nuclear Information System (INIS)

Ali, L.; Alam, W.; Abbas, M.A.; Ali, U.

2017-01-01

To compare three doses of hyperbaric 0.75% bupivacaine and measuring time for home readiness after day care perianal surgery under saddle block anaesthesia. Study Design: Non randomized controlled trial. Place and Duration of Study: The study was conducted at the department of Anaesthesia, CMH Rawalpindi from Jun 2014 to Apr 2015. Material and Methods: In this study 90 patients who presented for perianal day care surgery, were divided in three equal groups. Group A received 7.5 mg, group B 6.0 mg and group C 4.5 mg of hyperbaric 0.75% bupivacaine. Intrathecal injection was given in L4-5 space by 25 G spinal needle in sitting position. Lithotomy position was made after five minutes. After surgery patients were monitored in recovery room. After fulfilling ambulatory and discharge criteria patients were allowed to go home with attendants. Time of intrathecal injection, assessment of above criteria and time of discharge were noted and analyzed. Results: Male patients were 85.6% and females were 14.4%. Mean time of surgery was 48 +- 10.59 min. Mean time of discharge in minutes for group A was 235.86 +- 49.38, for group B 217.7 +- 42.49 and for group C 205.76 +- 32. Time of discharge was significantly different between group A and group C (p=0.02). While it was not significantly different between group A and group B (p=0.29) and between group B and group C (p=0.819). Conclusion: Lower dose of hyperbaric bupivacaine can reduce the time for home readiness compared to higher dose. Time of discharge is mainly dependent on time to micturate after saddle block anaesthesia. (author)

Grid generation methods

CERN Document Server

Liseikin, Vladimir D

2010-01-01

This book is an introduction to structured and unstructured grid methods in scientific computing, addressing graduate students, scientists as well as practitioners. Basic local and integral grid quality measures are formulated and new approaches to mesh generation are reviewed. In addition to the content of the successful first edition, a more detailed and practice oriented description of monitor metrics in Beltrami and diffusion equations is given for generating adaptive numerical grids. Also, new techniques developed by the author are presented, in particular a technique based on the inverted form of Beltrami’s partial differential equations with respect to control metrics. This technique allows the generation of adaptive grids for a wide variety of computational physics problems, including grid clustering to given function values and gradients, grid alignment with given vector fields, and combinations thereof. Applications of geometric methods to the analysis of numerical grid behavior as well as grid ge...

Smart grid technologies in local electric grids

Science.gov (United States)

Lezhniuk, Petro D.; Pijarski, Paweł; Buslavets, Olga A.

2017-08-01

The research is devoted to the creation of favorable conditions for the integration of renewable sources of energy into electric grids, which were designed to be supplied from centralized generation at large electric power stations. Development of distributed generation in electric grids influences the conditions of their operation - conflict of interests arises. The possibility of optimal functioning of electric grids and renewable sources of energy, when complex criterion of the optimality is balance reliability of electric energy in local electric system and minimum losses of electric energy in it. Multilevel automated system for power flows control in electric grids by means of change of distributed generation of power is developed. Optimization of power flows is performed by local systems of automatic control of small hydropower stations and, if possible, solar power plants.

Orientationally ordered ridge structures of aluminum films on hydrogen terminated silicon

DEFF Research Database (Denmark)

Quaade, Ulrich; Pantleon, Karen

2006-01-01

Films of aluminum deposited onto Si(100) substrates show a surface structure of parallel ridges. On films deposited on oxidized silicon substrates the direction of the ridges is arbitrary, but on films deposited on hydrogen-terminated Si(100) the ridges are oriented parallel to the < 110 > direct......Films of aluminum deposited onto Si(100) substrates show a surface structure of parallel ridges. On films deposited on oxidized silicon substrates the direction of the ridges is arbitrary, but on films deposited on hydrogen-terminated Si(100) the ridges are oriented parallel to the ... > directions on the silicon substrate. The ridge structure appears when the film thickness is above 500 nm, and increasing the film thickness makes the structure more distinct. Anodic oxidation enhances the structure even further. X-ray diffraction indicates that grains in the film have mostly (110) facets...

Tectonics of ridge-transform intersections at the Kane fracture zone

Science.gov (United States)

Karson, J. A.; Dick, H. J. B.

1983-03-01

The Kane Transform offsets spreading-center segments of the Mid-Atlantic Ridge by about 150 km at 24° N latitude. In terms of its first-order morphological, geological, and geophysical characteristics it appears to be typical of long-offset (>100 km), slow-slipping (2 cm yr-1) ridge-ridge transform faults. High-resolution geological observations were made from deep-towed ANGUS photographs and the manned submersible ALVIN at the ridge-transform intersections and indicate similar relationships in these two regions. These data indicate that over a distance of about 20 km as the spreading axes approach the fracture zone, the two flanks of each ridge axis behave in very different ways. Along the flanks that intersect the active transform zone the rift valley floor deepens and the surface expression of volcanism becomes increasingly narrow and eventually absent at the intersection where only a sediment-covered ‘nodal basin’ exists. The adjacent median valley walls have structural trends that are oblique to both the ridge and the transform and have as much as 4 km of relief. These are tectonically active regions that have only a thin (young volcanics passes laterally into median valley walls with a simple block-faulted character where only volcanic rocks have been found. Along strike toward the fracture zone, the youngest volcanics form linear constructional volcanic ridges that transect the entire width of the fracture zone valley. These volcanics are continuous with the older-looking, slightly faulted volcanic terrain that floors the non-transform fracture zone valleys. These observations document the asymmetric nature of seafloor spreading near ridge-transform intersections. An important implication is that the crust and lithosphere across different portions of the fracture zone will have different geological characteristics. Across the active transform zone two lithosphere plate edges formed at ridge-transform corners are faulted against one another. In the non

Greening the Grid - Advancing Solar, Wind, and Smart Grid Technologies (Spanish Version)

Energy Technology Data Exchange (ETDEWEB)

2016-04-01

This is the Spanish version of 'Greening the Grid - Advancing Solar, Wind, and Smart Grid Technologies'. Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid.

Micro grids toward the smart grid

International Nuclear Information System (INIS)

Guerrero, J.

2011-01-01

Worldwide electrical grids are expecting to become smarter in the near future, with interest in Microgrids likely to grow. A microgrid can be defined as a part of the grid with elements of prime energy movers, power electronics converters, distributed energy storage systems and local loads, that can operate autonomously but also interacting with main grid. Thus, the ability of intelligent Microgrids to operate in island mode or connected to the grid will be a keypoint to cope with new functionalities and the integration of renewable energy resources. The functionalities expected for these small grids are: black start operation, frequency and voltage stability, active and reactive power flow control, active power filter capabilities, and storage energy management. In this presentation, a review of the main concepts related to flexible Microgrids will be introduced, with examples of real Microgrids. AC and DC Microgrids to integrate renewable and distributed energy resources will also be presented, as well as distributed energy storage systems, and standardization issues of these Microgrids. Finally, Microgrid hierarchical control will be analyzed looking at three different levels: i) a primary control based on the droop method, including an output impedance virtual loop; ii) a secondary control, which enables restoring any deviations produced by the primary control; and iii) a tertiary control to manage the power flow between the microgrid and the external electrical distribution system.

Internal doses in Oak Ridge. The Internet beams

International Nuclear Information System (INIS)

Passchier, W.F.

1997-01-01

A brief overview is given of the information, presented by the Radiation Internal Dose Information Center (RIDIC) of the Oak Ridge Associated Universities in Oak Ridge, TN, USA, via Internet (www.orau.gov/ehsd/ridic.htm)

Optical dating of dune ridges on Rømø

DEFF Research Database (Denmark)

Madsen, Anni Tindahl; Murray, A. S.; Andersen, Thorbjørn Joest

2007-01-01

The application of optically stimulated luminescence (OSL) to the dating of recent aeolian sand ridges on Rømø, an island off the southwest coast of Denmark, is tested. These sand ridges began to form approximately 300 years ago, and estimates of the ages are available from historical records....... Samples for OSL dating were taken ~0.5 m below the crests of four different dune ridges; at least five samples were recovered from each ridge to test the internal consistency of the ages. Additional samples were recovered from the low lying areas in the swales and from the scattered dune formations......-defined building phases separated by inactive periods and the first major ridge formed ~235 years ago. This study demonstrates that optical dating can be successfully applied to these young aeolian sand deposits, and we conclude that OSL dating is a powerful chronological tool in studies of coastal change....

Smart grid security

CERN Document Server

Goel, Sanjay; Papakonstantinou, Vagelis; Kloza, Dariusz

2015-01-01

This book on smart grid security is meant for a broad audience from managers to technical experts. It highlights security challenges that are faced in the smart grid as we widely deploy it across the landscape. It starts with a brief overview of the smart grid and then discusses some of the reported attacks on the grid. It covers network threats, cyber physical threats, smart metering threats, as well as privacy issues in the smart grid. Along with the threats the book discusses the means to improve smart grid security and the standards that are emerging in the field. The second part of the b

The Grid2003 Production Grid Principles and Practice

CERN Document Server

Foster, I; Gose, S; Maltsev, N; May, E; Rodríguez, A; Sulakhe, D; Vaniachine, A; Shank, J; Youssef, S; Adams, D; Baker, R; Deng, W; Smith, J; Yu, D; Legrand, I; Singh, S; Steenberg, C; Xia, Y; Afaq, A; Berman, E; Annis, J; Bauerdick, L A T; Ernst, M; Fisk, I; Giacchetti, L; Graham, G; Heavey, A; Kaiser, J; Kuropatkin, N; Pordes, R; Sekhri, V; Weigand, J; Wu, Y; Baker, K; Sorrillo, L; Huth, J; Allen, M; Grundhoefer, L; Hicks, J; Luehring, F C; Peck, S; Quick, R; Simms, S; Fekete, G; Van den Berg, J; Cho, K; Kwon, K; Son, D; Park, H; Canon, S; Jackson, K; Konerding, D E; Lee, J; Olson, D; Sakrejda, I; Tierney, B; Green, M; Miller, R; Letts, J; Martin, T; Bury, D; Dumitrescu, C; Engh, D; Gardner, R; Mambelli, M; Smirnov, Y; Voeckler, J; Wilde, M; Zhao, Y; Zhao, X; Avery, P; Cavanaugh, R J; Kim, B; Prescott, C; Rodríguez, J; Zahn, A; McKee, S; Jordan, C; Prewett, J; Thomas, T; Severini, H; Clifford, B; Deelman, E; Flon, L; Kesselman, C; Mehta, G; Olomu, N; Vahi, K; De, K; McGuigan, P; Sosebee, M; Bradley, D; Couvares, P; De Smet, A; Kireyev, C; Paulson, E; Roy, A; Koranda, S; Moe, B; Brown, B; Sheldon, P

2004-01-01

The Grid2003 Project has deployed a multi-virtual organization, application-driven grid laboratory ("GridS") that has sustained for several months the production-level services required by physics experiments of the Large Hadron Collider at CERN (ATLAS and CMS), the Sloan Digital Sky Survey project, the gravitational wave search experiment LIGO, the BTeV experiment at Fermilab, as well as applications in molecular structure analysis and genome analysis, and computer science research projects in such areas as job and data scheduling. The deployed infrastructure has been operating since November 2003 with 27 sites, a peak of 2800 processors, work loads from 10 different applications exceeding 1300 simultaneous jobs, and data transfers among sites of greater than 2 TB/day. We describe the principles that have guided the development of this unique infrastructure and the practical experiences that have resulted from its creation and use. We discuss application requirements for grid services deployment and configur...

Mapping of grid faults and grid codes

DEFF Research Database (Denmark)

Iov, F.; Hansen, Anca Daniela; Sørensen, Poul Ejnar

loads of wind turbines. The goal is also to clarify and define possible new directions in the certification process of power plant wind turbines, namely wind turbines, which participate actively in the stabilisation of power systems. Practical experience shows that there is a need...... challenges for the design of both the electrical system and the mechanical structure of wind turbines. An overview over the frequency of grid faults and the grid connection requirements in different relevant countries is done in this report. The most relevant study cases for the quantification of the loads......The present report is a part of the research project ''Grid fault and designbasis for wind turbine'' supported by Energinet.dk through the grant PSO F&U 6319. The objective of this project is to investigate into the consequences of the new grid connection requirements for the fatigue and extreme...

Normalization Ridge Regression in Practice I: Comparisons Between Ordinary Least Squares, Ridge Regression and Normalization Ridge Regression.

Science.gov (United States)

Bulcock, J. W.

The problem of model estimation when the data are collinear was examined. Though the ridge regression (RR) outperforms ordinary least squares (OLS) regression in the presence of acute multicollinearity, it is not a problem free technique for reducing the variance of the estimates. It is a stochastic procedure when it should be nonstochastic and it…

Hydrodynamic role of longitudinal ridges in a leatherback turtle swimming

Science.gov (United States)

Bang, Kyeongtae; Kim, Jooha; Lee, Sang-Im; Choi, Haecheon

2015-11-01

The leatherback sea turtle (Dermochelys coriacea), the fastest swimmer and the deepest diver among marine turtles, has five longitudinal ridges on its carapace. These ridges are the most remarkable morphological features distinguished from other marine turtles. To investigate the hydrodynamic role of these ridges in the leatherback turtle swimming, we model a carapace with and without ridges by using three dimensional surface data of a stuffed leatherback turtle in the National Science Museum, Korea. The experiment is conducted in a wind tunnel in the ranges of the real leatherback turtle's Reynolds number (Re) and angle of attack (α). The longitudinal ridges function differently according to the flow condition (i.e. Re and α). At low Re and negative α that represent the swimming condition of hatchlings and juveniles, the ridges significantly decrease the drag by generating streamwise vortices and delaying the main separation. On the other hand, at high Re and positive α that represent the swimming condition of adults, the ridges suppress the laminar separation bubble near the front part by generating streamwise vortices and enhance the lift and lift-to-drag ratio. Supported by the NRF program (2011-0028032).

A Stationary Reference Frame Grid Synchronization System for Three-Phase Grid-Connected Power Converters Under Adverse Grid Conditions

DEFF Research Database (Denmark)

Rodríguez, P.; Luna, A.; Muñoz-Aguilar, R. S.

2012-01-01

synchronization method for three-phase three-wire networks, namely dual second-order generalized integrator (SOGI) frequency-locked loop. The method is based on two adaptive filters, implemented by using a SOGI on the stationary αβ reference frame, and it is able to perform an excellent estimation......Grid synchronization algorithms are of great importance in the control of grid-connected power converters, as fast and accurate detection of the grid voltage parameters is crucial in order to implement stable control strategies under generic grid conditions. This paper presents a new grid...

Equatorial segment of the mid-atlantic ridge

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

The Equatorial Segment of the Mid-Atlantic Ridge is a part of this mid-oceanic ridge limited by a cluster of fracture zones - Cape Verde, Marathon, Mercury, Vema, Doldrums, Vernadsky and Sierra Leone - in the North, and a similar cluster of fracture zones - St Paul, Romanche and Chain - in the South. During recent decades, following the publication of the 5. edition of the General Bathymetric Chart of the Oceans (GEBCO), there has been a great deal of geological-geophysical research and mapping of the World Ocean. The results have led to the development of a number of theories concerning the essential heterogeneity of the structure of the ocean floor and, in particular, the heterogeneity of the structure and segmentation of mid-oceanic ridges. Research on the nature of such segmentation is of great importance for an understanding of the processes of development of such ridges and oceanic basins as a whole. Chapter 20 is dedicated to the study of the atlantic ocean mantle by using (Th.U)Th, (Th/U)pb and K/Ti systematics 380 refs.

Equatorial segment of the mid-atlantic ridge

International Nuclear Information System (INIS)

1996-01-01

The Equatorial Segment of the Mid-Atlantic Ridge is a part of this mid-oceanic ridge limited by a cluster of fracture zones - Cape Verde, Marathon, Mercury, Vema, Doldrums, Vernadsky and Sierra Leone - in the North, and a similar cluster of fracture zones - St Paul, Romanche and Chain - in the South. During recent decades, following the publication of the 5. edition of the General Bathymetric Chart of the Oceans (GEBCO), there has been a great deal of geological-geophysical research and mapping of the World Ocean. The results have led to the development of a number of theories concerning the essential heterogeneity of the structure of the ocean floor and, in particular, the heterogeneity of the structure and segmentation of mid-oceanic ridges. Research on the nature of such segmentation is of great importance for an understanding of the processes of development of such ridges and oceanic basins as a whole. Chapter 20 is dedicated to the study of the atlantic ocean mantle by using (Th.U)Th, (Th/U)pb and K/Ti systematics

Equatorial segment of the mid-atlantic ridge

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

The Equatorial Segment of the Mid-Atlantic Ridge is a part of this mid-oceanic ridge limited by a cluster of fracture zones - Cape Verde, Marathon, Mercury, Vema, Doldrums, Vernadsky and Sierra Leone - in the North, and a similar cluster of fracture zones - St Paul, Romanche and Chain - in the South. During recent decades, following the publication of the 5. edition of the General Bathymetric Chart of the Oceans (GEBCO), there has been a great deal of geological-geophysical research and mapping of the World Ocean. The results have led to the development of a number of theories concerning the essential heterogeneity of the structure of the ocean floor and, in particular, the heterogeneity of the structure and segmentation of mid-oceanic ridges. Research on the nature of such segmentation is of great importance for an understanding of the processes of development of such ridges and oceanic basins as a whole. Chapter 20 is dedicated to the study of the atlantic ocean mantle by using (Th.U)Th, (Th/U)pb and K/Ti systematics 380 refs.

Does the lateral intercondylar ridge disappear in ACL deficient patients?

NARCIS (Netherlands)

van Eck, C.F.; Martins, C.A.Q.; Vyas, S.M.; Celentano, U.; van Dijk, C.N.; Fu, F.H.

2010-01-01

The aim of this study was to determine whether there is a difference in the presence of the lateral intercondylar ridge and the lateral bifurcate ridge between patients with sub-acute and chronic ACL injuries. We hypothesized that the ridges would be present less often with chronic ACL deficiency.

Mantle Convection beneath the Aegir Ridge, a Shadow in the Iceland Hotspot

Science.gov (United States)

Howell, S. M.; Ito, G.; Breivik, A. J.; Hanan, B. B.; Mjelde, R.; Sayit, K.; Vogt, P. R.

2012-12-01

The Iceland Hotspot has produced extensive volcanism spanning much of the ocean basin between Greenland and Norway, forming one of the world's largest igneous provinces. However, an apparent igneous "shadow" in hotspot activity is located at the fossil Aegir Ridge, which formed anomalously thin crust, despite this ridge being near the Iceland hotspot when it was active. The Aegir Ridge accommodated seafloor spreading northeast of present-day Iceland from the time of continental breakup at ~55 Ma until ~25 Ma, at which point spreading shifted west to the Kolbeinsey Ridge. To address the cause of the anomalously thin crust produced by the Aegir Ridge, we use three-dimensional numerical models to simulate the interaction between a mantle plume beneath the Iceland hotspot, rifting continental lithosphere, and the time-evolving North Atlantic ridge system. Two end-member hypotheses were investigated: (1) Material emanating from the Iceland mantle plume was blocked from reaching the Aegir Ridge by the thick lithosphere of the Jan Mayen Microcontinent as the Kolbeinsey Ridge began rifting it from Greenland at ~30 Ma, just east of the plume center; (2) Plume material was not blocked and did reach the Aegir Ridge, but had already experienced partial melting closer to the hotspot. This material was then unable to produce melt volumes at the Aegir Ridge comparable to those of pristine mantle. To test these hypotheses, we vary the volume flux and viscosity of the plume, and identify which conditions do and do not lead to the Aegir Ridge forming anomalously thin crust. Results show that the combination of plume material being drawn into the lithospheric channels beneath the Reykjanes Ridge and Kolbeinsey Ridge after their respective openings, and the impedance of plume flow by the Jan Mayen Microcontinent (hypothesis 1), can deprive the Aegir Ridge of plume influence. This leads to low crustal thicknesses that are comparable to those observed. We have yet to produce a model

Sex Determination from Fingerprint Ridge Density | Gungadin ...

African Journals Online (AJOL)

This study was conducted with an aim to establish a relationship between sex and fingerprint ridge density. The fingerprints were taken from 500 subjects (250 males and 250 females) in the age group of 18-60 years. After taking fingerprints, the ridges were counted in the upper portion of the radial border of each print for all ...

Bioinspired design of a ridging shovel with anti-adhesive and drag reducing

Directory of Open Access Journals (Sweden)

Zhijun Zhang

2015-03-01

Full Text Available Learning from the microstructure of the convex (concave and ridging (triangle and arc-shaped shapes of fresh lotus leaves and shark skin, bionic ridging shovels was designed with the characteristics of adhesion and resistance reduction. Ten ridging shovel models were established, and the interaction process with the soil by ANSYS is discussed. Stress analysis results showed that the bionic ridging shovel was more obvious in visbreaking and in the resistance reduction effect. An indoor soil bin experiment with the bionic ridging shovel and the prototype ridging shovel was operated as follows: the ridging resistance of the three types of ridging shovel was tested under the condition of two soil moistures (18.61% and 20.9% and three different ridging speeds (0.68, 0.87, and 1.11 m/s. In this article, the structure, the mechanism, and their relationship to the functions are discussed. The results of this study will be useful in practical application in the field of agricultural machinery toward practical use and industrialization.

GridICE: monitoring the user/application activities on the grid

International Nuclear Information System (INIS)

Aiftimiei, C; Pra, S D; Andreozzi, S; Fattibene, E; Misurelli, G; Cuscela, G; Donvito, G; Dudhalkar, V; Maggi, G; Pierro, A; Fantinel, S

2008-01-01

The monitoring of the grid user activity and application performance is extremely useful to plan resource usage strategies particularly in cases of complex applications. Large VOs, such as the LHC VOs, do their monitoring by means of dashboards. Other VOs or communities, like for example the BioinfoGRID one, are characterized by a greater diversification of the application types: so the effort to provide a dashboard like monitor is particularly heavy. The main theme of this paper is to show the improvements introduced in GridICE, a web tool built to provides an almost complete grid monitoring. These recent improvements allows GridICE to provide new reports on the resources usage with details of the VOMS groups, roles and users. By accessing the GridICE web pages, the grid user can get all information that is relevant to keep track of his activity on the grid. In the same way, the activity of a VOMS group can be distinguished from the activity of the entire VO. In this paper we briefly talk about the features and advantages of this approach and, after discussing the requirements, we describe the software solutions, middleware and prerequisite to manage and retrieve the user's credentials

Mapping of grid faults and grid codes

DEFF Research Database (Denmark)

Iov, Florin; Hansen, A.D.; Sørensen, P.

loads of wind turbines. The goal is also to clarify and define possible new directions in the certification process of power plant wind turbines, namely wind turbines, which participate actively in the stabilisation of power systems. Practical experience shows that there is a need...... challenges for the design of both the electrical system and the mechanical structure of wind turbines. An overview over the frequency of grid faults and the grid connection requirements in different relevant countries is done in this report. The most relevant study cases for the quantification of the loads......The present report is a part of the research project "Grid fault and design basis for wind turbine" supported by Energinet.dk through the grant PSO F&U 6319. The objective of this project is to investigate into the consequences of the new grid connection requirements for the fatigue and extreme...

A unified grid current control for grid-interactive DG inverters in microgrids

DEFF Research Database (Denmark)

Wang, Xiongfei; Loh, Poh Chiang; Blaabjerg, Frede

2015-01-01

This paper proposes a unified grid current control for grid-interactive distributed generation inverters. In the approach, the grid-side current, instead of inverter-side current, is controlled as an inner loop, while the filter capacitor voltage is indirectly regulated through a virtual admittan...... locus analyses in the discrete z-domain are performed for elaborating the controller design. Simulations and experimental results demonstrate the performances of the proposed approach.......This paper proposes a unified grid current control for grid-interactive distributed generation inverters. In the approach, the grid-side current, instead of inverter-side current, is controlled as an inner loop, while the filter capacitor voltage is indirectly regulated through a virtual admittance...... in the outer loop. It, therefore, provides several superior features over traditional control schemes: 1) high-quality grid current in the grid-connected mode, 2) inherent derivative-less virtual output impedance control, and 3) the unified active damping for both grid-connected and islanded operations. Root...

Europan double ridge morphometry as a test of formation models

Science.gov (United States)

Dameron, Ashley C.; Burr, Devon M.

2018-05-01

Double ridges on the Jovian satellite Europa consist of two parallel ridges with a central trough. Although these features are nearly ubiquitous on Europa, their formation mechanism(s) is (are) not yet well-understood. Previous hypotheses for their formation can be divided into two groups based on 1) the expected interior slope angles and 2) the magnitude of interior/exterior slope symmetry. The published hypotheses in the first ("fracture") group entail brittle deformation of the crust, either by diapirism, shear heating, or buckling due to compression. Because these mechanisms imply uplift of near-vertical fractures, their predicted interior slopes are steeper than the angle of repose (AOR) with shallower exterior slopes. The second ("flow") group includes cryosedimentary and cryovolcanic processes - explosive or effusive cryovolcanism and tidal squeezing -, which are predicted to form ridge slopes at or below the AOR. Explosive cryovolcanism would form self-symmetric ridges, whereas effusive cryolavas and cryo-sediments deposited during tidal squeezing would likely not exhibit slope symmetry. To distinguish between these two groups of hypothesized formation mechanisms, we derived measurements of interior slope angle and interior/exterior slope symmetry at multiple locations on Europa through analysis of data from the Galileo Solid State Imaging (SSI) camera. Two types of data were used: i) elevation data from five stereo-pair digital elevation models (DEMs) covering four ridges (580 individual measurements), and ii) ridge shadow length measurements taken on individual images over 40 ridges (200 individual measurements). Our results shows that slopes measured on our DEMs, located in the Cilix and Banded Plains regions, typically fall below the AOR, and slope symmetry is dominant. Two different shadow measurement techniques implemented to calculate interior slopes yielded slope angles that also fall below the AOR. The shallow interior slopes derived from both

The thermal structure of a wind-driven Reynolds ridge

Energy Technology Data Exchange (ETDEWEB)

Phongikaroon, Supathorn; Peter Judd, K.; Smith, Geoffrey B.; Handler, Robert A. [Remote Sensing Division, Naval Research Laboratory, 20375, Washington, DC (United States)

2004-08-01

In this study, we investigate the nature of a Reynolds ridge formed by wind shear. We have simultaneously imaged the water surface, with a deposit of a monolayer of the surfactant, oleyl alcohol, subject to different wind shears, by using a high-resolution infrared (IR) detector and a high-speed (HS) digital camera. The results reveal that the regions around the wind-driven Reynolds ridge, which have subtle manifestations in visual imagery, possess surprisingly complex hydrodynamical and thermal structures when observed in the infrared. The IR measurements reveal a warm, clean region upstream of the ridge, which is composed of the so called fishscale structures observed in earlier investigations. The region downstream of the ridge is composed of colder fluid which forms two counter-rotating cells. A region of intermediate temperature, which we call the mixing (wake) region, forms immediately downstream of the ridge near the channel centerline. By measuring the velocity of the advected fishscales, we have determined a surface drift speed of about 2% of the wind speed. The spanwise length-scale of the structures has also been used to estimate the wind shear. In addition, a comparison of IR and visual imagery shows that the thermal field is a very sensitive indicator of the exact position of the ridge itself. (orig.)

Grid-Voltage-Feedforward Active Damping for Grid-Connected Inverter with LCL Filter

DEFF Research Database (Denmark)

Lu, Minghui; Wang, Xiongfei; Blaabjerg, Frede

2016-01-01

For the grid-connected voltage source inverters, the feedforward scheme of grid voltage is commonly adopted to mitigate the current distortion caused by grid background voltages harmonics. This paper investigates the grid-voltage-feedforward active damping for grid connected inverter with LCL...... filter. It reveals that proportional feedforward control can not only fulfill the mitigation of grid disturbance, but also offer damping effects on the LCL filter resonance. Digital delays are intrinsic to digital controlled inverters; with these delays, the feedforward control can be equivalent...

Risk factors for saddle-related skin lesions on elephants used in the tourism industry in Thailand.

Science.gov (United States)

Magda, Scarlett; Spohn, Olivia; Angkawanish, Taweepoke; Smith, Dale A; Pearl, David L

2015-05-19

Lesions related to working conditions and improper saddle design are a concern for a variety of working animals including elephants. The objectives of the present study were to determine the prevalence of cutaneous lesions in anatomic regions (i.e., neck, girth, back, tail) in contact with saddle-related equipment among elephants in Thailand working in the tourism industry, and to identify potential risk factors associated with these lesions. Data for this cross-sectional study were collected between May 2007 and July 2007 on 194 elephants from 18 tourism camps across Thailand. There was a high prevalence (64.4 %; 95 % CI 57.3 - 71.2) of active lesions, most often located on the back region. Using multilevel multivariable logistic regression modelling containing a random intercept for camp we identified the following risk factors: increasing elephant age, the use of rice sacks as padding material in contact with the skin, and the provision of a break for the elephants. Working hours had a quadratic relationship with the log odds of an active lesion where the probability of an active lesion initially increased with the number of working hours per day and then declined possibly reflecting a "healthy worker" bias where only animals without lesions continue to be able to work these longer hours. While we recognize that the cross-sectional nature of the study posed some inferential limitations, our results offer several potential intervention points for the prevention of these lesions. Specifically, we recommend the following until longitudinal studies can be conducted: increased monitoring of older elephants and the back region of all elephants, working less than 6 hours per day, and the avoidance of rice sacks as padding material in contact with skin.

Strongly coupled interaction between a ridge of fluid and an inviscid airflow

KAUST Repository

Paterson, C.

2015-07-01

© 2015 AIP Publishing LLC. The behaviour of a steady thin sessile or pendent ridge of fluid on an inclined planar substrate which is strongly coupled to the external pressure gradient arising from an inviscid airflow parallel to the substrate far from the ridge is described. When the substrate is nearly horizontal, a very wide ridge can be supported against gravity by capillary and/or external pressure forces; otherwise, only a narrower (but still wide) ridge can be supported. Classical thin-aerofoil theory is adapted to obtain the governing singular integro-differential equation for the profile of the ridge in each case. Attention is focused mainly on the case of a very wide sessile ridge. The effect of strengthening the airflow is to push a pinned ridge down near to its edges and to pull it up near to its middle. At a critical airflow strength, the upslope contact angle reaches the receding contact angle at which the upslope contact line de-pins, and continuing to increase the airflow strength beyond this critical value results in the de-pinned ridge becoming narrower, thicker, and closer to being symmetric in the limit of a strong airflow. The effect of tilting the substrate is to skew a pinned ridge in the downslope direction. Depending on the values of the advancing and receding contact angles, the ridge may first de-pin at either the upslope or the downslope contact line but, in general, eventually both contact lines de-pin. The special cases in which only one of the contact lines de-pins are also considered. It is also shown that the behaviour of a very wide pendent ridge is qualitatively similar to that of a very wide sessile ridge, while the important qualitative difference between the behaviour of a very wide ridge and a narrower ridge is that, in general, for the latter one or both of the contact lines may never de-pin.

A roadmap for caGrid, an enterprise Grid architecture for biomedical research.

Science.gov (United States)

Saltz, Joel; Hastings, Shannon; Langella, Stephen; Oster, Scott; Kurc, Tahsin; Payne, Philip; Ferreira, Renato; Plale, Beth; Goble, Carole; Ervin, David; Sharma, Ashish; Pan, Tony; Permar, Justin; Brezany, Peter; Siebenlist, Frank; Madduri, Ravi; Foster, Ian; Shanbhag, Krishnakant; Mead, Charlie; Chue Hong, Neil

2008-01-01

caGrid is a middleware system which combines the Grid computing, the service oriented architecture, and the model driven architecture paradigms to support development of interoperable data and analytical resources and federation of such resources in a Grid environment. The functionality provided by caGrid is an essential and integral component of the cancer Biomedical Informatics Grid (caBIG) program. This program is established by the National Cancer Institute as a nationwide effort to develop enabling informatics technologies for collaborative, multi-institutional biomedical research with the overarching goal of accelerating translational cancer research. Although the main application domain for caGrid is cancer research, the infrastructure provides a generic framework that can be employed in other biomedical research and healthcare domains. The development of caGrid is an ongoing effort, adding new functionality and improvements based on feedback and use cases from the community. This paper provides an overview of potential future architecture and tooling directions and areas of improvement for caGrid and caGrid-like systems. This summary is based on discussions at a roadmap workshop held in February with participants from biomedical research, Grid computing, and high performance computing communities.

Site descriptions of environmental restoration units at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Kuhaida, A.J. Jr.; Parker, A.F.

1997-02-01

This report provides summary information on Oak Ridge National Laboratory (ORNL) Environmental Restoration (ER) sites as listed in the Oak Ridge Reservation Federal Facility Agreement (FFA), dated January 1, 1992, Appendix C. The Oak Ridge National Laboratory was built in 1943 as part of the World War II Manhattan Project. The original mission of ORNL was to produce and chemically separate the first gram-quantities of plutonium as part of the national effort to produce the atomic bomb. The current mission of ORNL is to provide applied research and development in support of the U.S. Department of Energy (DOE) programs in nuclear fusion and fission, energy conservation, fossil fuels, and other energy technologies and to perform basic scientific research in selected areas of the physical, life, and environmental sciences. ER is also tasked with clean up or mitigation of environmental impacts resulting from past waste management practices on portions of the approximately 37,000 acres within the Oak Ridge Reservation (ORR). Other installations located within the ORR are the Gaseous Diffusion Plant (K-25) and the Y-12 plant. The remedial action strategy currently integrates state and federal regulations for efficient compliance and approaches for both investigations and remediation efforts on a Waste Area Grouping (WAG) basis. As defined in the ORR FFA Quarterly Report July - September 1995, a WAG is a grouping of potentially contaminated sites based on drainage area and similar waste characteristics. These contaminated sites are further divided into four categories based on existing information concerning whether the data are generated for scoping or remedial investigation (RI) purposes. These areas are as follows: (1) Operable Units (OU); (2) Characterization Areas (CA); (3) Remedial Site Evaluation (RSE) Areas; and (4) Removal Site Evaluation (RmSE) Areas.

Urban micro-grids

International Nuclear Information System (INIS)

Faure, Maeva; Salmon, Martin; El Fadili, Safae; Payen, Luc; Kerlero, Guillaume; Banner, Arnaud; Ehinger, Andreas; Illouz, Sebastien; Picot, Roland; Jolivet, Veronique; Michon Savarit, Jeanne; Strang, Karl Axel

2017-02-01

ENEA Consulting published the results of a study on urban micro-grids conducted in partnership with the Group ADP, the Group Caisse des Depots, ENEDIS, Omexom, Total and the Tuck Foundation. This study offers a vision of the definition of an urban micro-grid, the value brought by a micro-grid in different contexts based on real case studies, and the upcoming challenges that micro-grid stakeholders will face (regulation, business models, technology). The electric production and distribution system, as the backbone of an increasingly urbanized and energy dependent society, is urged to shift towards a more resilient, efficient and environment-friendly infrastructure. Decentralisation of electricity production into densely populated areas is a promising opportunity to achieve this transition. A micro-grid enhances local production through clustering electricity producers and consumers within a delimited electricity network; it has the ability to disconnect from the main grid for a limited period of time, offering an energy security service to its customers during grid outages for example. However: The islanding capability is an inherent feature of the micro-grid concept that leads to a significant premium on electricity cost, especially in a system highly reliant on intermittent electricity production. In this case, a smart grid, with local energy production and no islanding capability, can be customized to meet relevant sustainability and cost savings goals at lower costs For industrials, urban micro-grids can be economically profitable in presence of high share of reliable energy production and thermal energy demand micro-grids face strong regulatory challenges that should be overcome for further development Whether islanding is or is not implemented into the system, end-user demand for a greener, more local, cheaper and more reliable energy, as well as additional services to the grid, are strong drivers for local production and consumption. In some specific cases

Grid Architecture 2

Energy Technology Data Exchange (ETDEWEB)

Taft, Jeffrey D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-01-01

The report describes work done on Grid Architecture under the auspices of the Department of Electricity Office of Electricity Delivery and Reliability in 2015. As described in the first Grid Architecture report, the primary purpose of this work is to provide stakeholder insight about grid issues so as to enable superior decision making on their part. Doing this requires the creation of various work products, including oft-times complex diagrams, analyses, and explanations. This report provides architectural insights into several important grid topics and also describes work done to advance the science of Grid Architecture as well.

GridOrbit public display

DEFF Research Database (Denmark)

Ramos, Juan David Hincapie; Tabard, Aurélien; Bardram, Jakob

2010-01-01

We introduce GridOrbit, a public awareness display that visualizes the activity of a community grid used in a biology laboratory. This community grid executes bioin-formatics algorithms and relies on users to donate CPU cycles to the grid. The goal of GridOrbit is to create a shared awareness about...

Maxillary anterior ridge augmentation with recombinant human bone morphogenetic protein 2.

Science.gov (United States)

Edmunds, Ryan K; Mealey, Brian L; Mills, Michael P; Thoma, Daniel S; Schoolfield, John; Cochran, David L; Mellonig, Jim

2014-01-01

No human studies exist on the use of recombinant human bone morphogenetic protein 2 (rhBMP-2) on an absorbable collagen sponge (ACS) as a sole graft material for lateral ridge augmentation in large ridge defect sites. This series evaluates the treatment outcome of maxillary anterior lateral ridge augmentation with rhBMP-2/ACS. Twenty patients were treated with rhBMP-2/ACS and fixation screws for space maintenance. Cone beam volumetric tomography measurements were used to determine gain in ridge width, and a bone core biopsy was obtained. The mean horizontal ridge gain was 1.2 mm across sites, and every site gained width.

Smart Grid: Network simulator for smart grid test-bed

International Nuclear Information System (INIS)

Lai, L C; Ong, H S; Che, Y X; Do, N Q; Ong, X J

2013-01-01

Smart Grid become more popular, a smaller scale of smart grid test-bed is set up at UNITEN to investigate the performance and to find out future enhancement of smart grid in Malaysia. The fundamental requirement in this project is design a network with low delay, no packet drop and with high data rate. Different type of traffic has its own characteristic and is suitable for different type of network and requirement. However no one understands the natural of traffic in smart grid. This paper presents the comparison between different types of traffic to find out the most suitable traffic for the optimal network performance.

The effects of ridging, row-spacing and seeding rate on carrot yield

Directory of Open Access Journals (Sweden)

S. TAIVALMAA

2008-12-01

Full Text Available Cool, wet spring weather often delays the early growth of carrots (Daucus carota L. in northern Europe. This effect may be partly obviated by sowing in ridges. Many types of ridges are used, but the most suitable for carrot cultivation under the conditions prevailing in northern Europe has yet to be determined. The effects of ridging, seeding rate and sowing system on the yield and visible quality of carrots were therefore studied in the field during three years. The highest yields were recorded for carrots sown in double rows on a narrow ridge. The effect of sowing system on mean root weight differed depending on the ridging regime. The mean weight of roots was higher for carrots cultivated on broad ridges than in other systems. Seeding rate had the most significant effect on mean root weight. For industrial purposes it is recommended that carrots be cultivated on broad ridges in double rows at low seeding rates with irrigation. The optimal cultivation technique for carrots destined for the fresh vegetable market would be narrow ridges sown in double rows at high seeding rates. The ridging system, seeding rate and row spacing did not appear to affect the external quality of roots. More detailed studies should be carried out to establish the effects of abiotic growth factors under different ridging regimes.;

The effects of ridging, row-spacing and seeding rate on carrot yield

Directory of Open Access Journals (Sweden)

Sanna-Liisa Taivalmaa

1997-12-01

Full Text Available Cool, wet spring weather often delays the early growth of carrots (Daucus carota L. in northern Europe. This effect may be partly obviated by sowing in ridges. Many types of ridges are used, but the most suitable for carrot cultivation under the conditions prevailing in northern Europe has yet to be determined. The effects of ridging, seeding rate and sowing system on the yield and visible quality of carrots were therefore studied in the field during three years. The highest yields were recorded for carrots sown in double rows on a narrow ridge. The effect of sowing system on mean root weight differed depending on the ridging regime. The mean weight of roots was higher for carrots cultivated on broad ridges than in other systems. Seeding rate had the most significant effect on mean root weight. For industrial purposes it is recommended that carrots be cultivated on broad ridges in double rows at low seeding rates with irrigation. The optimal cultivation technique for carrots destined for the fresh vegetable market would be narrow ridges sown in double rows at high seeding rates. The ridging system, seeding rate and row spacing did not appear to affect the external quality of roots. More detailed studies should be carried out to establish the effects of abiotic growth factors under different ridging regimes.

Unfaulting the Sardarapat Ridge, Southwest Armenia

Science.gov (United States)

Wetmore, P.; Connor, C.; Connor, L. J.; Savov, I. P.; Karakhanyan, A.

2012-12-01

Armenia is located near the core of contractional deformation associated with the collision between the Arabian and Eurasian tectonic plates. Several studies of this region, including portions of adjacent Georgia, Iran, and Turkey, have indicated that 1-2 mm/yr of intra-plate, north-south shortening is primarily accommodated by a network of E-W trending thrust faults, and NW-trending (dextral) and NE-trending (sinistral) strike-slip faults. One proposed fault in this network, the Sardarapat Fault (SF), was investigated as part of a regional seismic hazard assessment ahead of the installation of a replacement reactor at the Armenian Nuclear Power Plant (ANPP). The SF is primarily defined by the Sardarapat Ridge (SR), which is a WNW-trending, 40-70 m high topographic feature located just north of the Arax River and the Turkey-Armenia border. The stratigraphy comprising this ridge includes alluvium overlying several meters of lacustrine deposits above a crystal-rich basaltic lava flow that yields an Ar-Ar age of 0.9 +/- 0.02 Ma. The alluvial sediments on the ridge contain early Bronze age (3832-3470 BP) artifacts at an elevation 25 m above those of the surrounding alluvial plane. This has lead to the suggestion that the SR is bound to the south (the steepest side) by the SF, which is uplifting the ridge at a rate of 0.7 mm/yr. However, despite the prominence and trend of the ridge there are no unequivocal observations, such as scarps or exposures of fault rocks, to support the existence of the SF. The goal of the investigation of the SR area was to test various models for the formation of the ridge including faulting and combined volcanic and erosional processes. We therefore collected gravimetric, magnetic, magneto-tellurics (MT), and transient electromagnetic (TEM) data across an area of ~400 km2, and used correlations of stratigraphic data from coreholes drilled proximal to the study area to define the geometry of the contact between the basement and basin fill to

Grid Voltage Modulated Control of Grid-Connected Voltage Source Inverters under Unbalanced Grid Conditions

DEFF Research Database (Denmark)

Li, Mingshen; Gui, Yonghao; Quintero, Juan Carlos Vasquez

2017-01-01

In this paper, an improved grid voltage modulated control (GVM) with power compensation is proposed for grid-connected voltage inverters when the grid voltage is unbalanced. The objective of the proposed control is to remove the power ripple and to improve current quality. Three power compensation...... objectives are selected to eliminate the negative sequence components of currents. The modified GVM method is designed to obtain two separate second-order systems for not only the fast convergence rate of the instantaneous active and reactive powers but also the robust performance. In addition, this method...

EASE-Grid 2.0: Incremental but Significant Improvements for Earth-Gridded Data Sets

Directory of Open Access Journals (Sweden)

Matthew H. Savoie

2012-03-01

Full Text Available Defined in the early 1990s for use with gridded satellite passive microwave data, the Equal-Area Scalable Earth Grid (EASE-Grid was quickly adopted and used for distribution of a variety of satellite and in situ data sets. Conceptually easy to understand, EASE-Grid suffers from limitations that make it impossible to format in the widely popular GeoTIFF convention without reprojection. Importing EASE-Grid data into standard mapping software packages is nontrivial and error-prone. This article defines a standard for an improved EASE-Grid 2.0 definition, addressing how the changes rectify issues with the original grid definition. Data distributed using the EASE-Grid 2.0 standard will be easier for users to import into standard software packages and will minimize common reprojection errors that users had encountered with the original EASE-Grid definition.

Nonlinear multigrid solvers exploiting AMGe coarse spaces with approximation properties

DEFF Research Database (Denmark)

Christensen, Max la Cour; Vassilevski, Panayot S.; Villa, Umberto

2017-01-01

discretizations on general unstructured grids for a large class of nonlinear partial differential equations, including saddle point problems. The approximation properties of the coarse spaces ensure that our FAS approach for general unstructured meshes leads to optimal mesh-independent convergence rates similar...... to those achieved by geometric FAS on a nested hierarchy of refined meshes. In the numerical results, Newton’s method and Picard iterations with state-of-the-art inner linear solvers are compared to our FAS algorithm for the solution of a nonlinear saddle point problem arising from porous media flow...

Ambiguities in the grid-inefficiency correction for Frisch-Grid Ionization Chambers

International Nuclear Information System (INIS)

Al-Adili, A.; Hambsch, F.-J.; Bencardino, R.; Oberstedt, S.; Pomp, S.

2012-01-01

Ionization chambers with Frisch grids have been very successfully applied to neutron-induced fission-fragment studies during the past 20 years. They are radiation resistant and can be easily adapted to the experimental conditions. The use of Frisch grids has the advantage to remove the angular dependency from the charge induced on the anode plate. However, due to the Grid Inefficiency (GI) in shielding the charges, the anode signal remains slightly angular dependent. The correction for the GI is, however, essential to determine the correct energy of the ionizing particles. GI corrections can amount to a few percent of the anode signal. Presently, two contradicting correction methods are considered in literature. The first method adding the angular-dependent part of the signal to the signal pulse height; the second method subtracting the former from the latter. Both additive and subtractive approaches were investigated in an experiment where a Twin Frisch-Grid Ionization Chamber (TFGIC) was employed to detect the spontaneous fission fragments (FF) emitted by a 252 Cf source. Two parallel-wire grids with different wire spacing (1 and 2 mm, respectively), were used individually, in the same chamber side. All the other experimental conditions were unchanged. The 2 mm grid featured more than double the GI of the 1 mm grid. The induced charge on the anode in both measurements was compared, before and after GI correction. Before GI correction, the 2 mm grid resulted in a lower pulse-height distribution than the 1 mm grid. After applying both GI corrections to both measurements only the additive approach led to consistent grid independent pulse-height distributions. The application of the subtractive correction on the contrary led to inconsistent, grid-dependent results. It is also shown that the impact of either of the correction methods is small on the FF mass distributions of 235 U(n th , f).

Microgravity survey of the Oak Ridge K-25 Site, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Kaufmann, R.D.

1996-05-01

Karst features are known to exist within the carbonate bedrock of the Oak Ridge K-25 Site and may play an important role in groundwater flow and contaminant migration. This report discusses the results of a microgravity survey of the Oak Ridge K-25 Site. The main objective of the survey is to identify areas containing bedrock cavities. Secondary objectives included correlating the observed gravity to the geology and to variations in overburden thickness. The analysis includes 11 profile lines that are oriented perpendicular to the geologic strike and major structures throughout the K-25 Site. The profile lines are modeled in an effort to relate gravity anomalies to karst features such as concentrations of mud-filled cavities. Regolith thickness and density data provided by boreholes constrain the models. Areally distributed points are added to the profile lines to produce a gravity contour map of the site. In addition, data from the K-901 area are combined with data from previous surveys to produce a high resolution map of that site. The K-25 Site is located in an area of folded and faulted sedimentary rocks within the Appalachian Valley and Ridge physiographic province. Paleozoic age rocks of the Rome Formation, Knox Group, and Chickamauga Supergroup underlie the K-25 Site and contain structures that include the Whiteoak Mountain Fault, the K-25 Fault, a syncline, and an anticline. The mapped locations of the rock units and complex structures are currently derived from outcrop and well log analysis

Grid Transmission Expansion Planning Model Based on Grid Vulnerability

Science.gov (United States)

Tang, Quan; Wang, Xi; Li, Ting; Zhang, Quanming; Zhang, Hongli; Li, Huaqiang

2018-03-01

Based on grid vulnerability and uniformity theory, proposed global network structure and state vulnerability factor model used to measure different grid models. established a multi-objective power grid planning model which considering the global power network vulnerability, economy and grid security constraint. Using improved chaos crossover and mutation genetic algorithm to optimize the optimal plan. For the problem of multi-objective optimization, dimension is not uniform, the weight is not easy given. Using principal component analysis (PCA) method to comprehensive assessment of the population every generation, make the results more objective and credible assessment. the feasibility and effectiveness of the proposed model are validated by simulation results of Garver-6 bus system and Garver-18 bus.

A new preconditioner update strategy for the solution of sequences of linear systems in structural mechanics: application to saddle point problems in elasticity

Science.gov (United States)

Mercier, Sylvain; Gratton, Serge; Tardieu, Nicolas; Vasseur, Xavier

2017-12-01

Many applications in structural mechanics require the numerical solution of sequences of linear systems typically issued from a finite element discretization of the governing equations on fine meshes. The method of Lagrange multipliers is often used to take into account mechanical constraints. The resulting matrices then exhibit a saddle point structure and the iterative solution of such preconditioned linear systems is considered as challenging. A popular strategy is then to combine preconditioning and deflation to yield an efficient method. We propose an alternative that is applicable to the general case and not only to matrices with a saddle point structure. In this approach, we consider to update an existing algebraic or application-based preconditioner, using specific available information exploiting the knowledge of an approximate invariant subspace or of matrix-vector products. The resulting preconditioner has the form of a limited memory quasi-Newton matrix and requires a small number of linearly independent vectors. Numerical experiments performed on three large-scale applications in elasticity highlight the relevance of the new approach. We show that the proposed method outperforms the deflation method when considering sequences of linear systems with varying matrices.

Removal action report on the Building 3001 canal at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-05-01

Oak Ridge National Laboratory (ORNL) is a federal facility managed by Lockheed Martin C, Energy Research, Inc., for the U.S. Department of Energy (DOE). ORNL on the Oak Ridge Reservation in East Tennessee at the Anderson and Roane County lines, approximately 38 km (24 miles) west of Knoxville, Tennessee, and 18 km (11 miles) southwest of downtown Oak Ridge. The Oak Ridge Graphite Reactor and its storage and transfer canal are located in Bldg. 3001 in the approximate center of Waste Area Grouping I in the ORNL main complex. 4:1 The Bldg. 3001 Storage Canal is an L-shaped, underground, reinforced-concrete structure running from the back and below the Graphite Reactor in Bldg. 3001 to a location beneath a hot cell in the adjacent Bldg. 3019. The Graphite Reactor was built in 1943 to produce small quantities of plutonium and was subsequently used to produce other isotopes for medical research before it was finally shut down in 1963. The associated canal was used to transport, under water, spent fuel slugs and other isotopes from the back of the reactor to the adjacent Bldg. 31319 hot cell for further processing. During its operation and years subsequent to operation, the canal's concrete walls and floor became contaminated with radioisotopes from the water.This report documents the activities involved with replacing the canal water with a solid, controlled, low-strength material (CLSM) in response to a Comprehensive Environmental Response, Compensation, and Liability Act non-time-critical removal action

Transitions in axial morphology along the Southeast Indian Ridge

Science.gov (United States)

Ma, Ying; Cochran, James R.

1996-07-01

Shipboard bathymetric and magnetic profiles across the Southeast Indian Ridge (SEIR) were analyzed in order to examine the nature of along-axis variations in axial morphology at this intermediate spreading rate ridge. Three types of axial morphology are observed along the SEIR: an axial high, a shallow (200-700 m deep) axial valley and a deep (>1000 m deep) axial valley. An axial high is found to the east of the Australian-Antarctic Discordance (AAD) (east of 128°E) and between 82°E and 104°E. A shallow rift valley is found from 104°E to 114°E and from 82°E westward past the Amerstdam/St. Paul hotspot (ASP) to about 30°S, 75°E. Deep rift valleys are found from 114°E to 128°E in the vicinity of the AAD and from the Indian Ocean Triple Junction (IOTJ) at 25°S, 70°E to about 30°S, 75°E. The transition near 30°S occurs in an area of constant zero-age depth and does not appear to result from an increase in mantle temperature. It could be the result of the rapid increase in spreading rate along that portion of the SEIR. The most likely cause of the other transitions in axial morphology is variations in mantle temperature. The transitions between the different types of axial morphology are well defined and occur over a limited distance. Transitions in axial morphology are accompanied by significant changes in ridge flank topographic roughness. The transitions from axial valleys to axial highs are also accompanied by changes in the amplitude of the seafloor magnetic anomalies. Our observations suggest that there are distinct modes rather than a continuum of axial morphology on the SEIR and that there appears to be a "threshold" mechanism for a rapid change between different states of axial morphology. The ASP has only a limited influence on the SEIR. The ridge axis is marked by an axial valley for the entire distance from the IOTJ up to and past the ASP. The ridge axis becomes shallower as the ASP is approached from the northwest but only by about 300 m over

Accretion mode of oceanic ridges governed by axial mechanical strength

Science.gov (United States)

Sibrant, A. L. R.; Mittelstaedt, E.; Davaille, A.; Pauchard, L.; Aubertin, A.; Auffray, L.; Pidoux, R.

2018-04-01

Oceanic spreading ridges exhibit structural changes as a function of spreading rate, mantle temperature and the balance of tectonic and magmatic accretion. The role that these or other processes have in governing the overall shape of oceanic ridges is unclear. Here, we use laboratory experiments to simulate ridge spreading in colloidal aqueous dispersions whose rheology evolves from purely viscous to elastic and brittle when placed in contact with a saline water solution. We find that ridge shape becomes increasingly linear with spreading rate until reaching a minimum tortuosity. This behaviour is predicted by the axial failure parameter ΠF, a dimensionless number describing the balance of brittle and plastic failure of axial lithosphere. Slow-spreading, fault-dominated and fast-spreading, fluid intrusion-dominated ridges on Earth and in the laboratory are separated by the same critical ΠF value, suggesting that the axial failure mode governs ridge geometry. Values of ΠF can also be calculated for different mantle temperatures and applied to other planets or the early Earth. For higher mantle temperatures during the Archaean, our results preclude the predicted formation of large tectonic plates at high spreading velocity.

Alveolar Ridge Split Technique Using Piezosurgery with Specially Designed Tips

Directory of Open Access Journals (Sweden)

Alessandro Moro

2017-01-01

Full Text Available The treatment of patients with atrophic ridge who need prosthetic rehabilitation is a common problem in oral and maxillofacial surgery. Among the various techniques introduced for the expansion of alveolar ridges with a horizontal bone deficit is the alveolar ridge split technique. The aim of this article is to give a description of some new tips that have been specifically designed for the treatment of atrophic ridges with transversal bone deficit. A two-step piezosurgical split technique is also described, based on specific osteotomies of the vestibular cortex and the use of a mandibular ramus graft as interpositional graft. A total of 15 patients were treated with the proposed new tips by our department. All the expanded areas were successful in providing an adequate width and height to insert implants according to the prosthetic plan and the proposed tips allowed obtaining the most from the alveolar ridge split technique and piezosurgery. These tips have made alveolar ridge split technique simple, safe, and effective for the treatment of horizontal and vertical bone defects. Furthermore the proposed piezosurgical split technique allows obtaining horizontal and vertical bone augmentation.

Alveolar Ridge Split Technique Using Piezosurgery with Specially Designed Tips.

Science.gov (United States)

Moro, Alessandro; Gasparini, Giulio; Foresta, Enrico; Saponaro, Gianmarco; Falchi, Marco; Cardarelli, Lorenzo; De Angelis, Paolo; Forcione, Mario; Garagiola, Umberto; D'Amato, Giuseppe; Pelo, Sandro

2017-01-01

The treatment of patients with atrophic ridge who need prosthetic rehabilitation is a common problem in oral and maxillofacial surgery. Among the various techniques introduced for the expansion of alveolar ridges with a horizontal bone deficit is the alveolar ridge split technique. The aim of this article is to give a description of some new tips that have been specifically designed for the treatment of atrophic ridges with transversal bone deficit. A two-step piezosurgical split technique is also described, based on specific osteotomies of the vestibular cortex and the use of a mandibular ramus graft as interpositional graft. A total of 15 patients were treated with the proposed new tips by our department. All the expanded areas were successful in providing an adequate width and height to insert implants according to the prosthetic plan and the proposed tips allowed obtaining the most from the alveolar ridge split technique and piezosurgery. These tips have made alveolar ridge split technique simple, safe, and effective for the treatment of horizontal and vertical bone defects. Furthermore the proposed piezosurgical split technique allows obtaining horizontal and vertical bone augmentation.

Grid Databases for Shared Image Analysis in the MammoGrid Project

CERN Document Server

Amendolia, S R; Hauer, T; Manset, D; McClatchey, R; Odeh, M; Reading, T; Rogulin, D; Schottlander, D; Solomonides, T

2004-01-01

The MammoGrid project aims to prove that Grid infrastructures can be used for collaborative clinical analysis of database-resident but geographically distributed medical images. This requires: a) the provision of a clinician-facing front-end workstation and b) the ability to service real-world clinician queries across a distributed and federated database. The MammoGrid project will prove the viability of the Grid by harnessing its power to enable radiologists from geographically dispersed hospitals to share standardized mammograms, to compare diagnoses (with and without computer aided detection of tumours) and to perform sophisticated epidemiological studies across national boundaries. This paper outlines the approach taken in MammoGrid to seamlessly connect radiologist workstations across a Grid using an "information infrastructure" and a DICOM-compliant object model residing in multiple distributed data stores in Italy and the UK

Multigrid on unstructured grids using an auxiliary set of structured grids

Energy Technology Data Exchange (ETDEWEB)

Douglas, C.C.; Malhotra, S.; Schultz, M.H. [Yale Univ., New Haven, CT (United States)

1996-12-31

Unstructured grids do not have a convenient and natural multigrid framework for actually computing and maintaining a high floating point rate on standard computers. In fact, just the coarsening process is expensive for many applications. Since unstructured grids play a vital role in many scientific computing applications, many modifications have been proposed to solve this problem. One suggested solution is to map the original unstructured grid onto a structured grid. This can be used as a fine grid in a standard multigrid algorithm to precondition the original problem on the unstructured grid. We show that unless extreme care is taken, this mapping can lead to a system with a high condition number which eliminates the usefulness of the multigrid method. Theorems with lower and upper bounds are provided. Simple examples show that the upper bounds are sharp.

Asymmetrical Grid Fault Ride-Through Strategy of Three-phase Grid-connected Inverter Considering Network Impedance Impact in Low Voltage Grid

DEFF Research Database (Denmark)

Guo, Xiaoqiang; Zhang, Xue; Wang, Baocheng

2014-01-01

This letter presents a new control strategy of threephase grid-connected inverter for the positive sequence voltage recovery and negative sequence voltage reduction under asymmetrical grid faults. Unlike the conventional control strategy based on an assumption that the network impedance is mainly...... of the proposed solution for the flexible voltage support in a low-voltage grid, where thenetwork impedance is mainly resistive.......This letter presents a new control strategy of threephase grid-connected inverter for the positive sequence voltage recovery and negative sequence voltage reduction under asymmetrical grid faults. Unlike the conventional control strategy based on an assumption that the network impedance is mainly...... inductive, the proposed control strategy is more flexible and effective by considering the network impedance impact, which is of great importance for the high penetration of grid-connected renewable energy systems into low-voltage grids. The experimental tests are carried out to validate the effectiveness...

Alveolar Ridge Carcinoma. Two Cases Report

International Nuclear Information System (INIS)

Pupo Triguero, Raul J; Vivar Bauza, Miriam; Alvarez Infante, Elisa

2008-01-01

Two cases with alveolar ridge carcinoma due to prosthetist traumatism are discussed in this paper, after 9 and 10 years of using dental prosthesis. Both patients began with disturbance in the alveolar ridge. The clinical examination and biopsy showed a well differenced carcinoma. The treatment was radical surgery and radiotherapy in the first patient, and conservative surgery with radiotherapy in the second case .The patients had xerostomia after radiotherapy and the woman had difficulties with mastication. The advantages and disadvantages of the treatment were discussed, focused on the prevention and treatment for oral

ORLANDO - Oak Ridge Large Neutrino Detector

International Nuclear Information System (INIS)

Bugg, W.; Cohn, H.; Efremenko, Yu.; Fazely, A.; Gabriel, T.; Kamyshkov, Yu.; Plasil, F.; Svoboda, R.

1999-01-01

We discuss a proposal for construction of an Oak Ridge LArge Neutrino DetectOr (ORLANDO) to search for neutrino oscillations at the Spallation Neutron Source (SNS). A 4 MW SNS is proposed to be built at the Oak Ridge National Laboratory with the first stage to be operative around 2006. It will have two target stations, which makes it possible with a single detector to perform a neutrino oscillation search at two different distances. Initial plans for the placement of the detector and the discovery potential of such a detector are discussed

The GRID seminar

CERN Multimedia

CERN. Geneva HR-RFA

2006-01-01

The Grid infrastructure is a key part of the computing environment for the simulation, processing and analysis of the data of the LHC experiments. These experiments depend on the availability of a worldwide Grid infrastructure in several aspects of their computing model. The Grid middleware will hide much of the complexity of this environment to the user, organizing all the resources in a coherent virtual computer center. The general description of the elements of the Grid, their interconnections and their use by the experiments will be exposed in this talk. The computational and storage capability of the Grid is attracting other research communities beyond the high energy physics. Examples of these applications will be also exposed during the presentation.

Importance of Grid Center Arrangement

Science.gov (United States)

Pasaogullari, O.; Usul, N.

2012-12-01

In Digital Elevation Modeling, grid size is accepted to be the most important parameter. Despite the point density and/or scale of the source data, it is freely decided by the user. Most of the time, arrangement of the grid centers are ignored, even most GIS packages omit the choice of grid center coordinate selection. In our study; importance of the arrangement of grid centers is investigated. Using the analogy between "Raster Grid DEM" and "Bitmap Image", importance of placement of grid centers in DEMs are measured. The study has been conducted on four different grid DEMs obtained from a half ellipsoid. These grid DEMs are obtained in such a way that they are half grid size apart from each other. Resulting grid DEMs are investigated through similarity measures. Image processing scientists use different measures to investigate the dis/similarity between the images and the amount of different information they carry. Grid DEMs are projected to a finer grid in order to co-center. Similarity measures are then applied to each grid DEM pairs. These similarity measures are adapted to DEM with band reduction and real number operation. One of the measures gives function graph and the others give measure matrices. Application of similarity measures to six grid DEM pairs shows interesting results. These four different grid DEMs are created with the same method for the same area, surprisingly; thirteen out of 14 measures state that, the half grid size apart grid DEMs are different from each other. The results indicated that although grid DEMs carry mutual information, they have also additional individual information. In other words, half grid size apart constructed grid DEMs have non-redundant information.; Joint Probability Distributions Function Graphs

Initial results of local grid control using wind farms with grid support

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Poul; Hansen, Anca D.; Iov, F.; Blaabjerg, F.

2005-09-01

This report describes initial results with simulation of local grid control using wind farms with grid support. The focus is on simulation of the behaviour of the wind farms when they are isolated from the main grid and establish a local grid together with a few other grid components. The isolated subsystems used in the work presented in this report do not intend to simulate a specific subsystem, but they are extremely simplified single bus bar systems using only a few more components than the wind farm. This approach has been applied to make it easier to understand the dynamics of the subsystem. The main observation is that the fast dynamics of the wind turbines seem to be able to contribute significantly to the grid control, which can be useful where the wind farm is isolated with a subsystem from the main grid with surplus of generation. Thus, the fast down regulation of the wind farm using automatic frequency control can keep the subsystem in operation and thereby improve the reliability of the grid. (LN)

How should grid operators govern smart grid innovation projects? An embedded case study approach

International Nuclear Information System (INIS)

Reuver, Mark de; Lei, Telli van der; Lukszo, Zofia

2016-01-01

Grid operators increasingly have to collaborate with other actors in order to realize smart grid innovations. For routine maintenance, grid operators typically acquire technologies in one-off transactions, but the innovative nature of smart grid projects may require more collaborate relationships. This paper studies how a transactional versus relational approach to governing smart grid innovation projects affects incentives for other actors to collaborate. We analyse 34 cases of smart grid innovation projects based on extensive archival data as well as interviews. We find that projects relying on relational governance are more likely to provide incentives for collaboration. Especially non-financial incentives such as reputational benefits and shared intellectual property rights are more likely to be found in projects relying on relational governance. Policy makers that wish to stimulate smart grid innovation projects should consider stimulating long-term relationships between grid operators and third parties, because such relationships are more likely to produce incentives for collaboration. - Highlights: • Smart grids require collaboration between grid operators and other actors. • We contrast transactional and relational governance of smart grid projects. • Long-term relations produce more incentives for smart grid collaboration. • Non-financial incentives are more important in long-term relations. • Policy makers should stimulate long-term relations to stimulate smart grids.

Characterization of Slosh Damping for Ortho-Grid and Iso-Grid Internal Tank Structures

Science.gov (United States)

Westra, Douglas G.; Sansone, Marco D.; Eberhart, Chad J.; West, Jeffrey S.

2016-01-01

Grid stiffened tank structures such as Ortho-Grid and Iso-Grid are widely used in cryogenic tanks for providing stiffening to the tank while reducing mass, compared to tank walls of constant cross-section. If the structure is internal to the tank, it will positively affect the fluid dynamic behavior of the liquid propellant, in regard to fluid slosh damping. As NASA and commercial companies endeavor to explore the solar system, vehicles will by necessity become more mass efficient, and design margin will be reduced where possible. Therefore, if the damping characteristics of the Ortho-Grid and Iso-Grid structure is understood, their positive damping effect can be taken into account in the systems design process. Historically, damping by internal structures has been characterized by rules of thumb and for Ortho-Grid, empirical design tools intended for slosh baffles of much larger cross-section have been used. There is little or no information available to characterize the slosh behavior of Iso-Grid internal structure. Therefore, to take advantage of these structures for their positive damping effects, there is much need for obtaining additional data and tools to characterize them. Recently, the NASA Marshall Space Flight Center conducted both sub-scale testing and computational fluid dynamics (CFD) simulations of slosh damping for Ortho-Grid and Iso-Grid tanks for cylindrical tanks containing water. Enhanced grid meshing techniques were applied to the geometrically detailed and complex Ortho-Grid and Iso-Grid structures. The Loci-STREAM CFD program with the Volume of Fluid Method module for tracking and locating the water-air fluid interface was used to conduct the simulations. The CFD simulations were validated with the test data and new empirical models for predicting damping and frequency of Ortho-Grid and Iso-Grid structures were generated.

Robust Grid-Current-Feedback Resonance Suppression Method for LCL-Type Grid-Connected Inverter Connected to Weak Grid

DEFF Research Database (Denmark)

Zhou, Xiaoping; Zhou, Leming; Chen, Yandong

2018-01-01

In this paper, a robust grid-current-feedback reso-nance suppression (GCFRS) method for LCL-type grid-connected inverter is proposed to enhance the system damping without introducing the switching noise and eliminate the impact of control delay on system robustness against grid-impedance variation....... It is composed of GCFRS method, the full duty-ratio and zero-beat-lag PWM method, and the lead-grid-current-feedback-resonance-suppression (LGCFRS) method. Firstly, the GCFRS is used to suppress the LCL-resonant peak well and avoid introducing the switching noise. Secondly, the proposed full duty-ratio and zero......-beat-lag PWM method is used to elimi-nate the one-beat-lag computation delay without introducing duty cycle limitations. Moreover, it can also realize the smooth switching from positive to negative half-wave of the grid current and improve the waveform quality. Thirdly, the proposed LGCFRS is used to further...

The Mozambique Ridge: a document of massive multistage magmatism

Science.gov (United States)

Fischer, Maximilian D.; Uenzelmann-Neben, Gabriele; Jacques, Guillaume; Werner, Reinhard

2017-01-01

The Mozambique Ridge, a prominent basement high in the southwestern Indian Ocean, consists of four major geomorphological segments associated with numerous phases of volcanic activity in the Lower Cretaceous. The nature and origin of the Mozambique Ridge have been intensely debated with one hypothesis suggesting a Large Igneous Province origin. High-resolution seismic reflection data reveal a large number of extrusion centres with a random distribution throughout the southern Mozambique Ridge and the nearby Transkei Rise. Intrabasement reflections emerge from the extrusion centres and are interpreted to represent massive lava flow sequences. Such lava flow sequences are characteristic of eruptions leading to the formation of continental and oceanic flood basalt provinces, hence supporting a Large Igneous Province origin of the Mozambique Ridge. We observe evidence for widespread post-sedimentary magmatic activity that we correlate with a southward propagation of the East African Rift System. Based on our volumetric analysis of the southern Mozambique Ridge we infer a rapid sequential emplacement between ˜131 and ˜125 Ma, which is similar to the short formation periods of other Large Igneous Provinces like the Agulhas Plateau.

Grid connectivity issues and the importance of GCC. [GCC - Grid Code Compliance

Energy Technology Data Exchange (ETDEWEB)

Das, A.; Schwartz, M.-K. [GL Renewable Certification, Malleswaram, Bangalore (India)

2012-07-01

In India, the wind energy is concentrated in rural areas with a very high penetration. In these cases, the wind power has an increasing influence on the power quality on the grids. Another aspect is the influence of weak grids on the operation of wind turbines. Hence it becomes very much essential to introduce such a strong grid code which is particularly applicable to wind sector and suitable for Indian environmental grid conditions. This paper focuses on different international grid codes and their requirement with regard to the connection of wind farms to the electric power systems to mitigate the grid connectivity issues. The requirements include the ways to achieve voltage and frequency stability in the grid-tied wind power system. In this paper, comparative overview and analysis of the main grid connecting requirements will be conducted, comprising several national and regional codes from many countries where high wind penetration levels have been achieved or are expected in the future. The objective of these requirements is to provide wind farms with the control and regulation capabilities encountered in conventional power plants and are necessary for the safe, reliable and economic operation of the power system. This paper also provides a brief idea on the Grid Code Compliance (GCC) certification procedure implemented by the leading accredited certifying body like Germanischer Lloyd Renewables Certification (GL RC), who checks the conformity of the wind turbines as per region specific grid codes. (Author)

Beach ridge sedimentology: field observation and palaeoenvironmental interpretation for Anegada Island, British Virgin Islands.

Science.gov (United States)

Cescon, Anna Lisa; Cooper, J. Andrew G.; Jackson, Derek W. T.

2014-05-01

Beach ridge landforms have been observed in different environments and in settings that range from polar to tropical. Their stratigraphy and sedimentology has received a limited amount of discussion in the literature (Tamura, 2012). In coastal geomorphology a beach ridge can be seen as a transitional deposit between onshore and offshore environments. They are regarded as representing high level wave action along a coastline. In the Caribbean the origin of beach ridges has been variously attributed to one of three extreme wave events: extreme swell, extreme storm or tsunami waves. Beach ridges are arranged in beach ridge plains where there is succession of the landforms and can be several kilometres long. Beach ridge accumulation is not continuous and the coast shows alternating accretion and erosion periods. The use of beach ridges as palaeostorm archives is therefore not straightforward. The temporal continuity of beach ridge formation is being assessed on the beach ridge plains of Anegada, British Virgin Islands (Lesser Antilles). This carbonate platform surrounded by a fringing reef contains two beach ridge plains. There are more than 30 ridges in the Atlantic facing- coast and around 10 in the south, Caribbean- facing coast. The sediments of the modern beaches are dominated by the sand fraction and are 100% biogenic origin due to the isolation of Anegada from terrestrial sediment sources. The beach ridge sections have been studied in different area of Anegada beach ridge plains and present low angle seaward-dipping bedding. The sand fraction is dominant in the stratigraphy with a few intact shells. At only one site were coral pebbles deposited in association with the sand fraction. Aeolian deposits represent the upper part of the beach ridges and reflect the stabilization of the beach ridges with ongoing accretion. The sedimentology of the contemporary beach and dunes will be discussed in terms of their implications for understanding beach ridge genesis and its

Ridge Distance Estimation in Fingerprint Images: Algorithm and Performance Evaluation

Directory of Open Access Journals (Sweden)

Tian Jie

2004-01-01

Full Text Available It is important to estimate the ridge distance accurately, an intrinsic texture property of a fingerprint image. Up to now, only several articles have touched directly upon ridge distance estimation. Little has been published providing detailed evaluation of methods for ridge distance estimation, in particular, the traditional spectral analysis method applied in the frequency field. In this paper, a novel method on nonoverlap blocks, called the statistical method, is presented to estimate the ridge distance. Direct estimation ratio (DER and estimation accuracy (EA are defined and used as parameters along with time consumption (TC to evaluate performance of these two methods for ridge distance estimation. Based on comparison of performances of these two methods, a third hybrid method is developed to combine the merits of both methods. Experimental results indicate that DER is 44.7%, 63.8%, and 80.6%; EA is 84%, 93%, and 91%; and TC is , , and seconds, with the spectral analysis method, statistical method, and hybrid method, respectively.

One Piece Orbitozygomatic Approach Based on the Sphenoid Ridge Keyhole

DEFF Research Database (Denmark)

Spiriev, Toma; Poulsgaard, Lars; Fugleholm, Kåre

2016-01-01

The one-piece orbitozygomatic (OZ) approach is traditionally based on the McCarty keyhole. Here, we present the use of the sphenoid ridge keyhole and its possible advantages as a keyhole for the one-piece OZ approach. Using transillumination technique the osteology of the sphenoid ridge...... was examined on 20 anatomical dry skull specimens. The results were applied to one-piece OZ approaches performed on freshly frozen cadaver heads. We defined the center of the sphenoid ridge keyhole as a superficial projection on the lateral skull surface of the most anterior and thickest part of the sphenoid...... ridge. It was located 22 mm (standard deviation [SD], 0.22 mm) from the superior temporal line; 10.7 mm (SD, 0.08 mm) posterior and 7.1 mm (SD, 0.22 mm) inferior to the frontozygomatic suture. The sphenoid ridge burr hole provides exposure of frontal, temporal dura as well as periorbita, which...

Significance testing in ridge regression for genetic data

Directory of Open Access Journals (Sweden)

De Iorio Maria

2011-09-01

Full Text Available Abstract Background Technological developments have increased the feasibility of large scale genetic association studies. Densely typed genetic markers are obtained using SNP arrays, next-generation sequencing technologies and imputation. However, SNPs typed using these methods can be highly correlated due to linkage disequilibrium among them, and standard multiple regression techniques fail with these data sets due to their high dimensionality and correlation structure. There has been increasing interest in using penalised regression in the analysis of high dimensional data. Ridge regression is one such penalised regression technique which does not perform variable selection, instead estimating a regression coefficient for each predictor variable. It is therefore desirable to obtain an estimate of the significance of each ridge regression coefficient. Results We develop and evaluate a test of significance for ridge regression coefficients. Using simulation studies, we demonstrate that the performance of the test is comparable to that of a permutation test, with the advantage of a much-reduced computational cost. We introduce the p-value trace, a plot of the negative logarithm of the p-values of ridge regression coefficients with increasing shrinkage parameter, which enables the visualisation of the change in p-value of the regression coefficients with increasing penalisation. We apply the proposed method to a lung cancer case-control data set from EPIC, the European Prospective Investigation into Cancer and Nutrition. Conclusions The proposed test is a useful alternative to a permutation test for the estimation of the significance of ridge regression coefficients, at a much-reduced computational cost. The p-value trace is an informative graphical tool for evaluating the results of a test of significance of ridge regression coefficients as the shrinkage parameter increases, and the proposed test makes its production computationally feasible.

The GridShare solution: a smart grid approach to improve service provision on a renewable energy mini-grid in Bhutan

International Nuclear Information System (INIS)

Quetchenbach, T G; Harper, M J; Jacobson, A E; Robinson IV, J; Hervin, K K; Chase, N A; Dorji, C

2013-01-01

This letter reports on the design and pilot installation of GridShares, devices intended to alleviate brownouts caused by peak power use on isolated, village-scale mini-grids. A team consisting of the authors and partner organizations designed, built and field-tested GridShares in the village of Rukubji, Bhutan. The GridShare takes an innovative approach to reducing brownouts by using a low cost device that communicates the state of the grid to its users and regulates usage before severe brownouts occur. This demand-side solution encourages users to distribute the use of large appliances more evenly throughout the day, allowing power-limited systems to provide reliable, long-term renewable electricity to these communities. In the summer of 2011, GridShares were installed in every household and business connected to the Rukubji micro-hydro mini-grid, which serves approximately 90 households with a 40 kW nominal capacity micro-hydro system. The installation was accompanied by an extensive education program. Following the installation of the GridShares, the occurrence and average length of severe brownouts, which had been caused primarily by the use of electric cooking appliances during meal preparation, decreased by over 92%. Additionally, the majority of residents surveyed stated that now they are more certain that their rice will cook well and that they would recommend installing GridShares in other villages facing similar problems. (letter)

Bayesian grid matching

DEFF Research Database (Denmark)

Hartelius, Karsten; Carstensen, Jens Michael

2003-01-01

A method for locating distorted grid structures in images is presented. The method is based on the theories of template matching and Bayesian image restoration. The grid is modeled as a deformable template. Prior knowledge of the grid is described through a Markov random field (MRF) model which r...

Efficiency of local surface plasmon polariton excitation on ridges

DEFF Research Database (Denmark)

Radko, Ilya; Bozhevolnyi, Sergey I.; Boltasseva, Alexandra

2008-01-01

We investigate experimentally and numerically the efficiency of surface plasmon polariton excitation by a focused laser beam using gold ridges. The dependence of the efficiency on geometrical parameters of ridges and wavelength dependence are examined. The experimental measurements accomplished...

Storminess-related rhythmic ridge patterns on the coasts of Estonia

Directory of Open Access Journals (Sweden)

Ülo Suursaar

2017-11-01

Full Text Available Buried or elevated coastal ridges may serve as archives of past variations in sea level and climate conditions. Sometimes such ridges or coastal scarps appear in patterns, particularly on uplifting coasts with adequate sediment supply. Along the seacoasts of Estonia, where relative-to-geoid postglacial uplift can vary between 1.7 and 3.4 mm/yr, at least 27 areas with rhythmic geomorphic patterns have been identified from LiDAR images and elevation data. Such patterns were mainly found on faster emerging and well-exposed, tideless coasts. These are mostly located at heights between 1 and 21 m above sea level, the formation of which corresponds to a period of up to 7500 years. Up to approximately 150 individual ridges were counted on some cross-shore sections. Ten of these ridge patterns that formed less than 4500 years ago were chosen for detailed characterization and analysis in search of possible forcing mechanisms. Among these more closely studied cases, the mean ridge spacing varied between 19 and 28 m. Using land uplift rates from the late Holocene period, the timespans of the corresponding cross sections were calculated. The average temporal periodicity of the ridges was between 23 and 39 years with a gross mean value of 31 years. Considering the regular nature of the ridges, they mostly do not reflect single extreme events, but rather a decadal-scale periodicity in storminess in the region of the Baltic Sea. Although a contribution from some kind of self-organization process is possible, the rhythmicity in ancient coastal ridge patterns is likely linked to quasi-periodic 25−40-year variability, which can be traced to Estonian long-term sea level records and wave hindcasts, as well as in regional storminess data and the North Atlantic Oscillation index.

The LHCb Grid Simulation

CERN Multimedia

Baranov, Alexander

2016-01-01

The LHCb Grid access if based on the LHCbDirac system. It provides access to data and computational resources to researchers with different geographical locations. The Grid has a hierarchical topology with multiple sites distributed over the world. The sites differ from each other by their number of CPUs, amount of disk storage and connection bandwidth. These parameters are essential for the Grid work. Moreover, job scheduling and data distribution strategy have a great impact on the grid performance. However, it is hard to choose an appropriate algorithm and strategies as they need a lot of time to be tested on the real grid. In this study, we describe the LHCb Grid simulator. The simulator reproduces the LHCb Grid structure with its sites and their number of CPUs, amount of disk storage and bandwidth connection. We demonstrate how well the simulator reproduces the grid work, show its advantages and limitations. We show how well the simulator reproduces job scheduling and network anomalies, consider methods ...

Slow light effect with high group index and wideband by saddle-like mode in PC-CROW

Science.gov (United States)

Wan, Yong; Jiang, Li-Jun; Xu, Sheng; Li, Meng-Xue; Liu, Meng-Nan; Jiang, Cheng-Yi; Yuan, Feng

2018-04-01

Slow light with high group index and wideband is achieved in photonic crystal coupled-resonator optical waveguides (PC-CROWs). According to the eye-shaped scatterers and various microcavities, saddle-like curves between the normalized frequency f and wave number k can be obtained by adjusting the parameters of the scatterers, parameters of the coupling microcavities, and positions of the scatterers. Slow light with decent flat band and group index can then be achieved by optimizing the parameters. Simulations prove that the maximal value of the group index is > 104, and the normalized delay bandwidth product within a new varying range of n g > 102 or n g > 103 can be a new and effective criterion of evaluation for the slow light in PC-CROWs.

Smart grid in Denmark 2.0. Implementing three key recommendations from the Smart Grid Network. [DanGrid]; Smart Grid i Danmark 2.0. Implementering af tre centrale anbefalinger fra Smart Grid netvaerket

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-11-01

In 2011 the Smart Grid Network, established by the Danish Climate and Energy minister in 2010, published a report which identifies 35 recommendations for implementing smart grid in Denmark. The present report was prepared by the Danish Energy Association and Energinet.dk and elaborates three of these recommendations: Concept for controlling the power system; Information model for the dissemination of data; Roadmap for deployment of smart grid. Concept of Smart Grid: The concept mobilizes and enables electric power demand response and production from smaller customers. This is done by customers or devices connected to the power system modify their behavior to meet the needs of the power system. The concept basically distinguishes between two different mechanisms to enable flexibility. One is the use of price signals (variable network tariffs and electricity prices), which gives customers a financial incentive to move their electricity consumption and production to times when it is of less inconvenience to the power system. The second is flexibility products, where a pre-arranged and well-specified performance - for example, a load reduction in a defined network area - can be activated as required by grid operators and / or Energinet.dk at an agreed price. Information Model for Disseminating Data: The future power system is complex with a large number of physical units, companies and individuals are actively involved in the power system. Similarly, the amount of information needed to be collected, communicated and processed grows explosively, and it is therefore essential to ensure a well-functioning IT infrastructure. A crucial element is a standardized information model in the Danish power system. The concept therefore indicates to use international standards to define an information model. Roadmap Focusing on Grid Companies' Role: There is a need to remove two key barriers. The first barrier is that the existing regulation does not support the grid using

Synchronization method for grid integrated battery storage systems during asymmetrical grid faults

Directory of Open Access Journals (Sweden)

Popadić Bane

2017-01-01

Full Text Available This paper aims at presenting a robust and reliable synchronization method for battery storage systems during asymmetrical grid faults. For this purpose, a Matlab/Simulink based model for testing of the power electronic interface between the grid and the battery storage systems has been developed. The synchronization method proposed in the paper is based on the proportional integral resonant controller with the delay signal cancellation. The validity of the synchronization method has been verified using the advanced laboratory station for the control of grid connected distributed energy sources. The proposed synchronization method has eliminated unfavourable components from the estimated grid angular frequency, leading to the more accurate and reliable tracking of the grid voltage vector positive sequence during both the normal operation and the operation during asymmetrical grid faults. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 042004: Integrated and Interdisciplinary Research entitled: Smart Electricity Distribution Grids Based on Distribution Management System and Distributed Generation

Melton Valley Storage Tanks Capacity Increase Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1995-04-01

The US Department of Energy (DOE) proposes to construct and maintain additional storage capacity at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee, for liquid low-level radioactive waste (LLLW). New capacity would be provided by a facility partitioned into six individual tank vaults containing one 100,000 gallon LLLW storage tank each. The storage tanks would be located within the existing Melton Valley Storage Tank (MVST) facility. This action would require the extension of a potable water line approximately one mile from the High Flux Isotope Reactor (HFIR) area to the proposed site to provide the necessary potable water for the facility including fire protection. Alternatives considered include no-action, cease generation, storage at other ORR storage facilities, source treatment, pretreatment, and storage at other DOE facilities

The Effects of Ridge Axis Width on Mantle Melting at Mid-Ocean Ridges

Science.gov (United States)

Montesi, L.; Magni, V.; Gaina, C.

2017-12-01

Mantle upwelling in response to plate divergence produces melt at mid-ocean ridges. Melt starts when the solidus is crossed and stops when conductive cooling overcomes heat advection associated with the upwelling. Most mid-ocean ridge models assume that divergence takes place only in a narrow zone that defines the ridge axis, resulting in a single upwelling. However, more complex patterns of divergence are occasionally observed. The rift axis can be 20 km wide at ultraslow spreading center. Overlapping spreading center contain two parallel axes. Rifting in backarc basins is sometimes organized as a series of parallel spreading centers. Distributing plate divergence over several rifts reduces the intensity of upwelling and limits melting. Can this have a significant effect on the expected crustal thickness and on the mode of melt delivery at the seafloor? We address this question by modeling mantle flow and melting underneath two spreading centers separated by a rigid block. We adopt a non-linear rheology that includes dislocation creep, diffusion creep and yielding and include hydrothermal cooling by enhancing thermal conductivity where yielding takes place. The crustal thickness decreases if the rifts are separated by 30 km or more but only if the half spreading rate is between 1 and 2 cm/yr. At melting depth, a single upwelling remains the norm until the separation of the rifts exceeds a critical value ranging from 15 km in the fastest ridges to more than 50 km at ultraslow spreading centers. The stability of the central upwelling is due to hydrothermal cooling, which prevents hot mantle from reaching the surface at each spreading center. When hydrothermal cooling is suppressed, or the spreading centers are sufficiently separated, the rigid block becomes extremely cold and separates two distinct, highly asymmetric upwellings that may focus melt beyond the spreading center. In that case, melt delivery might drive further and further the divergence centers, whereas

Flexible operation of parallel grid-connecting converters under unbalanced grid voltage

DEFF Research Database (Denmark)

Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.

2017-01-01

-link voltage ripple, and overloading. Moreover, under grid voltage unbalance, the active power delivery ability is decreased due to the converter's current rating limitation. In this paper, a thorough study on the current limitation of the grid-connecting converter under grid voltage unbalance is conducted....... In addition, based on the principle that total output active power should be oscillation free, a coordinated control strategy is proposed for the parallel grid-connecting converters. The case study has been conducted to demonstrate the effectiveness of this proposed control strategy....

Oak Ridge Reservation Site Management Plan for the Environmental Restoration Program

Energy Technology Data Exchange (ETDEWEB)

1994-06-01

This site management plan for the Oak Ridge Reservation (ORR) describes the overall approach for addressing environmental contamination problems at the ORR Superfund site located in eastern Tennessee. The ORR consists of three major US Department of Energy (DOE) installations constructed in the early to mid 1940s as research, development, and process facilities in support of the Manhattan Project. In addition to the three installations -- Oak Ridge National Laboratory (ORNL), the Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion Plant) -- the ORR Superfund Site also includes areas outside the installations, land used by the Oak Ridge Associated Universities and waterways that have been contaminated by releases from the DOE installations. To date, {approximately} 400 areas (Appendix A) requiring evaluation have been identified. Cleanup of the ORR is expected to take two to three decades and cost several billion dollars. This site management plan provides a blueprint to guide this complex effort to ensure that the investigation and cleanup activities are carried out in an efficient and cost-effective manner.

Oak Ridge Reservation Site Management Plan for the Environmental Restoration Program

International Nuclear Information System (INIS)

1994-06-01

This site management plan for the Oak Ridge Reservation (ORR) describes the overall approach for addressing environmental contamination problems at the ORR Superfund site located in eastern Tennessee. The ORR consists of three major US Department of Energy (DOE) installations constructed in the early to mid 1940s as research, development, and process facilities in support of the Manhattan Project. In addition to the three installations -- Oak Ridge National Laboratory (ORNL), the Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion Plant) -- the ORR Superfund Site also includes areas outside the installations, land used by the Oak Ridge Associated Universities and waterways that have been contaminated by releases from the DOE installations. To date, ∼ 400 areas (Appendix A) requiring evaluation have been identified. Cleanup of the ORR is expected to take two to three decades and cost several billion dollars. This site management plan provides a blueprint to guide this complex effort to ensure that the investigation and cleanup activities are carried out in an efficient and cost-effective manner

Phase-lock loop of Grid-connected Voltage Source Converter under non-ideal grid condition

DEFF Research Database (Denmark)

Wang, Haojie; Sun, Hai; Han, Minxiao

2015-01-01

It is a normal practice that the DC micro-grid is connected to AC main grid through Grid-connected Voltage Source Converter (G-VSC) for voltage support. Accurate control of DC micro-grid voltage is difficult for G-VSC under unbalanced grid condition as the fundamental positive-sequence component...... and distorted system voltage the proposed PLL can accurately detect the fundamental positive-sequence component of grid voltage thus accurate control of DC micro-grid voltage can be realized....... phase information cannot be accurately tracked. Based on analysis of the cause of double-frequency ripple when unbalance exists in main grid, a phase-locked loop (PLL) detection technique is proposed. Under the conditions of unsymmetrical system voltage, varying system frequency, single-phase system...

Stress concentration factors at saddle and crown positions on the central brace of two-planar welded CHS DKT-connections

Science.gov (United States)

Ahmadi, Hamid; Lotfollahi-Yaghin, Mohammad Ali; Aminfar, Mohammad H.

2012-03-01

A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions. The analysis results were used to present general remarks on the effects of the geometrical parameters on stress concentration factors (SCFs) at the inner saddle, outer saddle, and crown positions on the central brace. Based on results of finite element (FE) analysis and through nonlinear regression analysis, a new set of SCF parametric equations was established for fatigue design purposes. An assessment study of equations was conducted against the experimental data and original SCF database. The satisfaction of acceptance criteria proposed by the UK Department of Energy (UK DoE) was also checked. Results of parametric study showed that highly remarkable differences exist between the SCF values in a multi-planar DKT-joint and the corresponding SCFs in an equivalent uni-planar KT-joint having the same geometrical properties. It can be clearly concluded from this observation that using the equations proposed for uni-planar KT-connections to compute the SCFs in multi-planar DKT-joints will lead to either considerably under-predicting or over-predicting results. Hence, it is necessary to develop SCF formulae specially designed for multi-planar DKT-joints. Good results of equation assessment according to UK DoE acceptance criteria, high values of correlation coefficients, and the satisfactory agreement between the predictions of the proposed equations and the experimental data guarantee the accuracy of the equations. Therefore, the developed equations can be reliably used for fatigue design of offshore structures.

Smart grid security innovative solutions for a modernized grid

CERN Document Server

Skopik, Florian

2015-01-01

The Smart Grid security ecosystem is complex and multi-disciplinary, and relatively under-researched compared to the traditional information and network security disciplines. While the Smart Grid has provided increased efficiencies in monitoring power usage, directing power supplies to serve peak power needs and improving efficiency of power delivery, the Smart Grid has also opened the way for information security breaches and other types of security breaches. Potential threats range from meter manipulation to directed, high-impact attacks on critical infrastructure that could bring down regi

Grid Integration Research | Wind | NREL

Science.gov (United States)

Grid Integration Research Grid Integration Research Researchers study grid integration of wind three wind turbines with transmission lines in the background. Capabilities NREL's grid integration electric power system operators to more efficiently manage wind grid system integration. A photo of

EASE-Grid 2.0: Incremental but Significant Improvements for Earth-Gridded Data Sets

OpenAIRE

Brodzik, Mary J.; Billingsley, Brendan; Haran, Terry; Raup, Bruce; Savoie, Matthew H.

2012-01-01

Defined in the early 1990s for use with gridded satellite passive microwave data, the Equal-Area Scalable Earth Grid (EASE-Grid) was quickly adopted and used for distribution of a variety of satellite and in situ data sets. Conceptually easy to understand, EASE-Grid suffers from limitations that make it impossible to format in the widely popular GeoTIFF convention without reprojection. Importing EASE-Grid data into standard mapping software packages is nontrivial and error-prone. This article...

Geophysical investigations over a segment of the Central Indian Ridge, Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

KameshRaju, K.A.; Ramprasad, T.; Subrahmanyam, C.

Swath bathymetric, gravity, and magnetic studies were carried out over a 55 km long segment of the Central Indian Ridge. The ridge is characterized by 12 to 15 km wide rift valley bounded by steep walls and prominent volcanic constructional ridges...

Model reduction method using variable-separation for stochastic saddle point problems

Science.gov (United States)

Jiang, Lijian; Li, Qiuqi

2018-02-01

In this paper, we consider a variable-separation (VS) method to solve the stochastic saddle point (SSP) problems. The VS method is applied to obtain the solution in tensor product structure for stochastic partial differential equations (SPDEs) in a mixed formulation. The aim of such a technique is to construct a reduced basis approximation of the solution of the SSP problems. The VS method attempts to get a low rank separated representation of the solution for SSP in a systematic enrichment manner. No iteration is performed at each enrichment step. In order to satisfy the inf-sup condition in the mixed formulation, we enrich the separated terms for the primal system variable at each enrichment step. For the SSP problems by regularization or penalty, we propose a more efficient variable-separation (VS) method, i.e., the variable-separation by penalty method. This can avoid further enrichment of the separated terms in the original mixed formulation. The computation of the variable-separation method decomposes into offline phase and online phase. Sparse low rank tensor approximation method is used to significantly improve the online computation efficiency when the number of separated terms is large. For the applications of SSP problems, we present three numerical examples to illustrate the performance of the proposed methods.

SuperGrid or SmartGrid: Competing strategies for large-scale integration of intermittent renewables?

International Nuclear Information System (INIS)

Blarke, Morten B.; Jenkins, Bryan M.

2013-01-01

This paper defines and compares two strategies for integrating intermittent renewables: SuperGrid and SmartGrid. While conventional energy policy suggests that these strategies may be implemented alongside each other, the paper identifies significant technological and socio-economic conflicts of interest between the two. The article identifies differences between a domestic strategy for the integration of intermittent renewables, vis-à-vis the SmartGrid, and a cross-system strategy, vis-à-vis the SuperGrid. Policy makers and transmission system operators must understand the need for both strategies to evolve in parallel, but in different territories, or with strategic integration, avoiding for one strategy to undermine the feasibility of the other. A strategic zoning strategy is introduced from which attentive societies as well as the global community stand to benefit. The analysis includes a paradigmatic case study from West Denmark which supports the hypothesis that these strategies are mutually exclusive. The case study shows that increasing cross-system transmission capacity jeopardizes the feasibility of SmartGrid technology investments. A political effort is required for establishing dedicated SmartGrid innovation zones, while also redefining infrastructure to avoid the narrow focus on grids and cables. SmartGrid Investment Trusts could be supported from reallocation of planned transmission grid investments to provide for the equitable development of SmartGrid strategies. - Highlights: • Compares SuperGrid and SmartGrid strategies for integrating intermittent renewables. • Identifies technological and socio-economic conflicts of interest between the two. • Proposes a strategic zoning strategy allowing for both strategies to evolve. • Presents a paradigmatic case study showing that strategies are mutually exclusive. • Proposes dedicated SmartGrid innovation zones and SmartGrid investment trusts

Nonlinear Forecasting With Many Predictors Using Kernel Ridge Regression

DEFF Research Database (Denmark)

Exterkate, Peter; Groenen, Patrick J.F.; Heij, Christiaan

This paper puts forward kernel ridge regression as an approach for forecasting with many predictors that are related nonlinearly to the target variable. In kernel ridge regression, the observed predictor variables are mapped nonlinearly into a high-dimensional space, where estimation of the predi...

Geology of Gable Mountain-Gable Butte Area

International Nuclear Information System (INIS)

Fecht, K.R.

1978-09-01

Gable Mountain and Gable Butte are two ridges which form the only extensive outcrops of the Columbia River Basalt Group in the central portion of the Pasco Basin. The Saddle Mountains Basalt and two interbedded sedimentary units of the Ellensburg Formation crop out on the ridges. These include, from oldest to youngest, the Asotin Member (oldest), Esquatzel Member, Selah Interbed, Pomona Member, Rattlesnake Ridge Interbed, and Elephant Mountain Member (youngest). A fluvial plain composed of sediments from the Ringold and Hanford (informal) formations surrounds these ridges. The structure of Gable Mountain and Gable Butte is dominated by an east-west-trending major fold and northwest-southeast-trending parasitic folds. Two faults associated with the uplift of these structures were mapped on Gable Mountain. The geomorphic expression of the Gable Mountain-Gable Butte area resulted from the comlex folding and subsequent scouring by post-basalt fluvial systems

Mapping of grid faults and grid codes[Wind turbines

Energy Technology Data Exchange (ETDEWEB)

Iov, F. [Aalborg Univ., Inst. of Energy Technology (Denmark); Hansen, Anca D.; Soerensen, Poul; Cutululis, N.A. [Risoe National Lab. - DTU, Wind Enegy Dept., Roskilde (Denmark)

2007-06-15

The objective of this project is to investigate into the consequences of the new grid connection requirements for the fatigue and extreme loads of wind turbines. The goal is also to clarify and define possible new directions in the certification process of power plant wind turbines, namely wind turbines, which participate actively in the stabilisation of power systems. Practical experience shows that there is a need for such investigations. The grid connection requirements for wind turbines have increased significantly during the last 5-10 years. Especially the requirements for wind turbines to stay connected to the grid during and after voltage sags, imply potential challenges in the design of wind turbines. These requirements pose challenges for the design of both the electrical system and the mechanical structure of wind turbines. An overview over the frequency of grid faults and the grid connection requirements in different relevant countries is done in this report. The most relevant study cases for the quantification of the loads' impact on the wind turbines' lifetime are defined. The goal of this report is to present a mapping of different grid fault types and their frequency in different countries. The report provides also a detailed overview of the Low Voltage Ride-Through Capabilities for wind turbines in different relevant countries. The most relevant study cases for the quantification of the loads' impact on the wind turbines' lifetime are defined. (au)

Bus.py: A GridLAB-D Communication Interface for Smart Distribution Grid Simulations

Energy Technology Data Exchange (ETDEWEB)

Hansen, Timothy M.; Palmintier, Bryan; Suryanarayanan, Siddharth; Maciejewski, Anthony A.; Siegel, Howard Jay

2015-07-03

As more Smart Grid technologies (e.g., distributed photovoltaic, spatially distributed electric vehicle charging) are integrated into distribution grids, static distribution simulations are no longer sufficient for performing modeling and analysis. GridLAB-D is an agent-based distribution system simulation environment that allows fine-grained end-user models, including geospatial and network topology detail. A problem exists in that, without outside intervention, once the GridLAB-D simulation begins execution, it will run to completion without allowing the real-time interaction of Smart Grid controls, such as home energy management systems and aggregator control. We address this lack of runtime interaction by designing a flexible communication interface, Bus.py (pronounced bus-dot-pie), that uses Python to pass messages between one or more GridLAB-D instances and a Smart Grid simulator. This work describes the design and implementation of Bus.py, discusses its usefulness in terms of some Smart Grid scenarios, and provides an example of an aggregator-based residential demand response system interacting with GridLAB-D through Bus.py. The small scale example demonstrates the validity of the interface and shows that an aggregator using said interface is able to control residential loads in GridLAB-D during runtime to cause a reduction in the peak load on the distribution system in (a) peak reduction and (b) time-of-use pricing cases.

Site characterization of the West Chestnut Ridge site

International Nuclear Information System (INIS)

Ketelle, R.H.; Huff, D.D.

1984-09-01

This report summarizes the results of investigations performed to date on the West Chestnut Ridge Site, on the Department of Energy (DOE) Oak Ridge Reservation. The investigations performed include geomorphic observations, areal geologic mapping, surficial soil mapping, subsurface investigations, soil geochemical and mineralogical analyses, geohydrologic testing, groundwater fluctuation monitoring, and surface water discharge and precipitation monitoring. 33 references, 32 figures, 24 tables

Profitability of smart grid solutions applied in power grid

Directory of Open Access Journals (Sweden)

Katić Nenad A.

2016-01-01

Full Text Available The idea of a Smart Grid solution has been developing for years, as complete solution for a power utility, consisting of different advanced technologies aimed at improving of the efficiency of operation. The trend of implementing various smart systems continues, e.g. Energy Management Systems, Grid Automation Systems, Advanced Metering Infrastructure, Smart power equipment, Distributed Energy Resources, Demand Response systems, etc. Futhermore, emerging technologies, such as energy storages, electrical vehicles or distributed generators, become integrated in distribution networks and systems. Nowadays, the idea of a Smart Grid solution becomes more realistic by full integration of all advanced operation technologies (OT within IT environment, providing the complete digitalization of an Utility (IT/OT integration. The overview of smart grid solutions, estimation of investments, operation costs and possible benefits are presented in this article, with discusison about profitability of such systems.

Multimode Interference: Identifying Channels and Ridges in Quantum Probability Distributions

OpenAIRE

O'Connell, Ross C.; Loinaz, Will

2004-01-01

The multimode interference technique is a simple way to study the interference patterns found in many quantum probability distributions. We demonstrate that this analysis not only explains the existence of so-called "quantum carpets," but can explain the spatial distribution of channels and ridges in the carpets. With an understanding of the factors that govern these channels and ridges we have a limited ability to produce a particular pattern of channels and ridges by carefully choosing the ...

Theoretical analysis of ridge gratings for long-range surface plasmon polaritons

DEFF Research Database (Denmark)

Søndergaard, Thomas; Bozhevolnyi, Sergey I.; Boltasseva, Alexandra

2006-01-01

Optical properties of ridge gratings for long-range surface plasmon polaritons (LRSPPs) are analyzed theoretically in a two-dimensional configuration via the Lippmann-Schwinger integral equation method. LRSPPs being supported by a thin planar gold film embedded in dielectric are considered...... to be scattered by an array of equidistant gold ridges on each side of the film designed for in-plane Bragg scattering of LRSPPs at the wavelength ~1550 nm. Out-of-plane scattering (OUPS), LRSPP transmission, reflection, and absorption are investigated with respect to the wavelength, the height of the ridges...... peak it is preferable to use longer gratings with smaller ridges compared to gratings with larger ridges, because the former result in a smaller OUPS from the grating facets than the latter. The theoretical analysis and its conclusions are supported with experimental results on the LRSPP reflection...

Application of synchronous grid-connected controller in the wind-solar-storage micro grid

OpenAIRE

Li, Hua; Ren, Yongfeng; Li, Le; Luo, Zhenpeng

2016-01-01

Recently, there has been an increasing interest in using distributed generators (DG) not only to inject power into the grid, but also to enhance the power quality. In this study, a space voltage pulse width modulation (SVPWM) control method is proposed for a synchronous grid-connected controller in a wind-solar-storage micro grid. This method is based on the appropriate topology of the synchronous controller. The wind-solar-storage micro grid is controlled to reconnect to the grid synchronous...

Analysis of turbine-grid interaction of grid-connected wind turbine using HHT

Science.gov (United States)

Chen, A.; Wu, W.; Miao, J.; Xie, D.

2018-05-01

This paper processes the output power of the grid-connected wind turbine with the denoising and extracting method based on Hilbert Huang transform (HHT) to discuss the turbine-grid interaction. At first, the detailed Empirical Mode Decomposition (EMD) and the Hilbert Transform (HT) are introduced. Then, on the premise of decomposing the output power of the grid-connected wind turbine into a series of Intrinsic Mode Functions (IMFs), energy ratio and power volatility are calculated to detect the unessential components. Meanwhile, combined with vibration function of turbine-grid interaction, data fitting of instantaneous amplitude and phase of each IMF is implemented to extract characteristic parameters of different interactions. Finally, utilizing measured data of actual parallel-operated wind turbines in China, this work accurately obtains the characteristic parameters of turbine-grid interaction of grid-connected wind turbine.

Grid generation methods

CERN Document Server

Liseikin, Vladimir D

2017-01-01

This new edition provides a description of current developments relating to grid methods, grid codes, and their applications to actual problems. Grid generation methods are indispensable for the numerical solution of differential equations. Adaptive grid-mapping techniques, in particular, are the main focus and represent a promising tool to deal with systems with singularities. This 3rd edition includes three new chapters on numerical implementations (10), control of grid properties (11), and applications to mechanical, fluid, and plasma related problems (13). Also the other chapters have been updated including new topics, such as curvatures of discrete surfaces (3). Concise descriptions of hybrid mesh generation, drag and sweeping methods, parallel algorithms for mesh generation have been included too. This new edition addresses a broad range of readers: students, researchers, and practitioners in applied mathematics, mechanics, engineering, physics and other areas of applications.

Wind tunnel experiments on the effects of tillage ridge features on wind erosion horizontal fluxes

Directory of Open Access Journals (Sweden)

M. Kardous

2005-11-01

Full Text Available In addition to the well-known soil factors which control wind erosion on flat, unridged surfaces, two specific processes affect the susceptibility of tillage ridged surfaces to wind erosion: ridge-induced roughness and ridge- trapping efficiency. In order to parameterize horizontal soil fluxes produced by wind over tillage ridges, eight-ridge configurations composed of sandy soil and exhibiting ridge heights to ridge spacing (RH/RS ratios ranging from 0.18 to 0.38 were experimented in a wind tunnel. These experiments are used to develop a parameterization of the horizontal fluxes over tillage ridged surfaces based only on the geometric characteristics of the ridges. Indeed, the key parameters controlling the horizontal flux, namely the friction velocity, threshold friction velocity and the adjustment coefficient, are derived through specific expressions, from ridge heights (RH and ridge spacing (RS. This parameterization was evaluated by comparing the results of the simulations to an additional experimental data set and to the data set obtained by Hagen and Armbrust (1992. In both cases, predicted and measured values are found to be in a satisfying agreement. This parameterization was used to evaluate the efficiency of ridges in reducing wind erosion. The results show that ridged surfaces, when compared to a loose, unridged soil surface, lead to an important reduction in the horizontal fluxes (exceeding 60%. Moreover, the effect of ridges in trapping particles contributes for more than 90% in the flux reduction while the ridge roughness effect is weak and decreases when the wind velocity increases.

Magnetic Anomalies over the Mid-Atlantic Ridge near 27{degrees}N.

Science.gov (United States)

Phillips, J D

1967-08-25

Ten magnetic profiles across the mid-Atlantic ridge near 27 degrees N show trends that are parallel to the ridge axis and symmetrical about the ridge axis. The configuration of magnetic bodies that could account for the pattern supports the Vine and Matthews hypothesis for the origin of magnetic anomalies over oceanic ridges. A polarity-reversal time scale inferred from models for sea-floor spreading in the Pacific-Antarctic ridge and radiometrically dated reversals of the geomagnetic field indicates a spreading rate of 1.25 centimeters per year during the last 6 million years and a rate of 1.65 centimeters per year between 6 and 10 million years ago. A similar analysis of more limited data over the mid-Atlantic ridge near 22 degrees N also indicates a change in the spreading rate. Here a rate of 1.4 centimeters per year appears to have been in effect during the last 5 million years; between 5 and 9 million years ago, an increased rate of 1.7 centimeters per year is indicated. The time of occurrence and relative magnitude of these changes in the spreading rate, about 5 to 6 million years ago and 18 to 27 percent, respectively, accords with the spreading rate change implied for the Juan de Fuca ridge in the northeast Pacific.

Site characterization plan for groundwater in Waste Area Grouping 1 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Lee, R.R.; Curtis, A.H.; Houlberg, L.M.; Purucker, S.T.; Singer, M.L.; Tardiff, M.F.; Wolf, D.A.

1994-07-01

The Waste Area Grouping (WAG) 1 Groundwater Operable Unit (OU) at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, is undergoing a site characterization to identify environmental contamination that may be present. This document, Site Characterization Report for Groundwater in Waste Area Grouping I at Oak Ridge National Laboratory, Oak Ridge, Tennessee, identifies areas of concern with respect to WAG 1 groundwater and presents the rationale, justification, and objectives for conducting this continuing site characterization. This report summarizes the operations that have taken place at each of the areas of concern in WAG 1, summarizes previous characterization studies that have been performed, presents interpretations of previously collected data and information, identifies contaminants of concern, and presents an action plan for further site investigations and early actions that will lead to identification of contaminant sources, their major groundwater pathways, and reduced off-site migration of contaminated groundwater to surface water. Site characterization Activities performed to date at WAG I have indicated that groundwater contamination, principally radiological contamination, is widespread. An extensive network of underground pipelines and utilities have contributed to the dispersal of contaminants to an unknown extent. The general absence of radiological contamination in surface water at the perimeter of WAG 1 is attributed to the presence of pipelines and underground waste storage tank sumps and dry wells distributed throughout WAG 1 which remove more than about 40 million gal of contaminated groundwater per year.

Site characterization plan for groundwater in Waste Area Grouping 1 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Lee, R.R.; Curtis, A.H.; Houlberg, L.M.; Purucker, S.T.; Singer, M.L.; Tardiff, M.F.; Wolf, D.A.

1994-07-01

The Waste Area Grouping (WAG) 1 Groundwater Operable Unit (OU) at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, is undergoing a site characterization to identify environmental contamination that may be present. This document, Site Characterization Report for Groundwater in Waste Area Grouping I at Oak Ridge National Laboratory, Oak Ridge, Tennessee, identifies areas of concern with respect to WAG 1 groundwater and presents the rationale, justification, and objectives for conducting this continuing site characterization. This report summarizes the operations that have taken place at each of the areas of concern in WAG 1, summarizes previous characterization studies that have been performed, presents interpretations of previously collected data and information, identifies contaminants of concern, and presents an action plan for further site investigations and early actions that will lead to identification of contaminant sources, their major groundwater pathways, and reduced off-site migration of contaminated groundwater to surface water. Site characterization Activities performed to date at WAG I have indicated that groundwater contamination, principally radiological contamination, is widespread. An extensive network of underground pipelines and utilities have contributed to the dispersal of contaminants to an unknown extent. The general absence of radiological contamination in surface water at the perimeter of WAG 1 is attributed to the presence of pipelines and underground waste storage tank sumps and dry wells distributed throughout WAG 1 which remove more than about 40 million gal of contaminated groundwater per year

Tracking coherent structures in massively-separated and turbulent flows

Science.gov (United States)

Rockwood, Matthew; Huang, Yangzi; Green, Melissa

2018-01-01

Coherent vortex structures are tracked in simulations of massively-separated and turbulent flows. Topological Lagrangian saddle points are found using intersections of the positive and negative finite-time Lyapunov exponent ridges, and these points are then followed in order to track individual coherent structure motion both in a complex interacting three-dimensional flow (turbulent channel) and during vortex formation (two-dimensional bluff body shedding). For a simulation of wall-bounded turbulence in a channel flow, tracking Lagrangian saddles shows that the average structure convection speed exhibits a similar trend as a previously published result based on velocity and pressure correlations, giving validity to the method. When this tracking method is applied in a study of a circular cylinder in cross-flow it shows that Lagrangian saddles rapidly accelerate away from the cylinder surface as the vortex sheds. This saddle behavior is compared with the time-resolved static pressure distribution on the circular cylinder, yielding locations on a cylinder surface where common sensors could detect this phenomenon, which is not available from force measurements or vortex circulation calculations. The current method of tracking coherent structures yields insight into the behavior of the coherent structures in both of the diverse flows presented, highlighting the breadth of its potential application.

Extraction of lead and ridge characteristics from SAR images of sea ice

Science.gov (United States)

Vesecky, John F.; Smith, Martha P.; Samadani, Ramin

1990-01-01

Image-processing techniques for extracting the characteristics of lead and pressure ridge features in SAR images of sea ice are reported. The methods are applied to a SAR image of the Beaufort Sea collected from the Seasat satellite on October 3, 1978. Estimates of lead and ridge statistics are made, e.g., lead and ridge density (number of lead or ridge pixels per unit area of image) and the distribution of lead area and orientation as well as ridge length and orientation. The information derived is useful in both ice science and polar operations for such applications as albedo and heat and momentum transfer estimates, as well as ship routing and offshore engineering.

Bear Creek Valley Floodplain Hot Spot Removal Action Project Plan, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1998-01-01

The Bear Creek Valley Floodplain Hot Spot Removal Action Project Plan, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (Y/ER-301) was prepared (1) to safely, cost-effectively, and efficiently evaluate the environmental impact of solid material in the two debris areas in the context of industrial land uses (as defined in the Bear Creek Valley Feasibility Study) to support the Engineering Evaluation/Cost Assessment and (2) to evaluate, define, and implement the actions to mitigate these impacts. This work was performed under Work Breakdown Structure 1.x.01.20.01.08

Submarine sand ridges and sand waves in the eastern part of the China Sea

Science.gov (United States)

Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

2016-04-01

Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

Calendar Year 2008 Groundwater Monitoring Report, U.S. Department of Energy Y-12 National Security Complex, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Elvado Environmental LLC

2009-12-01

This report contains the groundwater and surface water monitoring data that were obtained during calendar year (CY) 2008 at the U.S. Department of Energy (DOE) Y-12 National Security Complex (hereafter referenced as Y-12) on the DOE Oak Ridge Reservation (ORR) in Oak Ridge, Tennessee. The CY 2008 monitoring data were obtained from wells, springs, and surface water sampling locations in three hydrogeologic regimes at Y-12 (Figure A.1). The Bear Creek Hydrogeologic Regime (Bear Creek Regime) encompasses a section of Bear Creek Valley (BCV) between the west end of Y-12 and the west end of the Bear Creek Watershed (directions are in reference to the Y-12 grid system). The Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime) encompasses the Y-12 industrial facilities and support structures in BCV. The Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime) encompasses a section of Chestnut Ridge directly south of Y-12. Section 2 of this report provides background information pertinent to groundwater and surface water quality monitoring in each hydrogeologic regime, including the topography and bedrock geology, surface water drainage, groundwater system, and extent of groundwater contamination. The CY 2008 groundwater and surface water monitoring data in this report were obtained from sampling and analysis activities implemented under the Y-12 Groundwater Protection Program (GWPP) managed by Babcock & Wilcox Technical Services Y-12, LLC (B&W Y-12) and from sampling and analysis activities implemented under several monitoring programs managed by Bechtel Jacobs Company LLC (BJC). Cooperative implementation of the monitoring programs directed by the Y-12 GWPP and BJC (i.e., coordinating sample collection and sharing data) ensures that the CY 2008 monitoring results fulfill requirements of all the applicable monitoring drivers with no duplication of sampling and analysis efforts. Section 3 of this report contains a summary of information regarding the

A Generic Danish Distribution Grid Model for Smart Grid Technology Testing

DEFF Research Database (Denmark)

Cha, Seung-Tae; Wu, Qiuwei; Østergaard, Jacob

2012-01-01

This paper describes the development of a generic Danish distribution grid model for smart grid technology testing based on the Bornholm power system. The frequency dependent network equivalent (FDNE) method has been used in order to accurately preserve the desired properties and characteristics...... as a generic Smart Grid benchmark model for testing purposes....... by comparing the transient response of the original Bornholm power system model and the developed generic model under significant fault conditions. The results clearly show that the equivalent generic distribution grid model retains the dynamic characteristics of the original system, and can be used...

Impact of grid impedance variations on harmonic emission of grid-connected inverters

DEFF Research Database (Denmark)

Hoseinzadeh, Bakhtyar; Bak, Claus Leth; Blaabjerg, Frede

2017-01-01

This paper addresses harmonic magnification due to resonance circuits resulting from interaction between uncertain grid impedance and converter. The source of harmonic may be either the grid or inverter. It is demonstrated that unknown and unpredictable grid impedance may result in variable...

Beyond grid security

International Nuclear Information System (INIS)

Hoeft, B; Epting, U; Koenig, T

2008-01-01

While many fields relevant to Grid security are already covered by existing working groups, their remit rarely goes beyond the scope of the Grid infrastructure itself. However, security issues pertaining to the internal set-up of compute centres have at least as much impact on Grid security. Thus, this talk will present briefly the EU ISSeG project (Integrated Site Security for Grids). In contrast to groups such as OSCT (Operational Security Coordination Team) and JSPG (Joint Security Policy Group), the purpose of ISSeG is to provide a holistic approach to security for Grid computer centres, from strategic considerations to an implementation plan and its deployment. The generalised methodology of Integrated Site Security (ISS) is based on the knowledge gained during its implementation at several sites as well as through security audits, and this will be briefly discussed. Several examples of ISS implementation tasks at the Forschungszentrum Karlsruhe will be presented, including segregation of the network for administration and maintenance and the implementation of Application Gateways. Furthermore, the web-based ISSeG training material will be introduced. This aims to offer ISS implementation guidance to other Grid installations in order to help avoid common pitfalls

Grid simulator for power quality assessment of micro-grids

DEFF Research Database (Denmark)

Carrasco, Joaquin Eloy Garcia; Vasquez, Juan Carlos; Guerrero, Josep M.

2013-01-01

voltages, low-order harmonics and flicker. The aim of this equipment is to test the performance of a given system under such distorted voltages. A prototype of the simulator, consisting of two inverters connected back-to-back to a 380 V three-phase grid and feeding a micro-grid composed of two......-inverter interfaced distributed generators and a critical load was built and tested. A set of experimental results for linear purely resistive loads, non-linear loads and current-controlled inverters is presented to prove the capabilities of the simulator. Finally, a case study is presented by testing a micro-grid.......In this study, a grid simulator based on a back-to-back inverter topology with resonant controllers is presented. The simulator is able to generate three-phase voltages for a range of amplitudes and frequencies with different types of perturbations, such as voltage sags, steady-state unbalanced...

Wind tunnel experiments on the effects of tillage ridge features on wind erosion horizontal fluxes

Directory of Open Access Journals (Sweden)

M. Kardous

2005-11-01

Full Text Available In addition to the well-known soil factors which control wind erosion on flat, unridged surfaces, two specific processes affect the susceptibility of tillage ridged surfaces to wind erosion: ridge-induced roughness and ridge- trapping efficiency.

In order to parameterize horizontal soil fluxes produced by wind over tillage ridges, eight-ridge configurations composed of sandy soil and exhibiting ridge heights to ridge spacing (RH/RS ratios ranging from 0.18 to 0.38 were experimented in a wind tunnel. These experiments are used to develop a parameterization of the horizontal fluxes over tillage ridged surfaces based only on the geometric characteristics of the ridges. Indeed, the key parameters controlling the horizontal flux, namely the friction velocity, threshold friction velocity and the adjustment coefficient, are derived through specific expressions, from ridge heights (RH and ridge spacing (RS. This parameterization was evaluated by comparing the results of the simulations to an additional experimental data set and to the data set obtained by Hagen and Armbrust (1992. In both cases, predicted and measured values are found to be in a satisfying agreement.

This parameterization was used to evaluate the efficiency of ridges in reducing wind erosion. The results show that ridged surfaces, when compared to a loose, unridged soil surface, lead to an important reduction in the horizontal fluxes (exceeding 60%. Moreover, the effect of ridges in trapping particles contributes for more than 90% in the flux reduction while the ridge roughness effect is weak and decreases when the wind velocity increases.

Geophysical survey work plan for White Wing Scrap Yard (Waste Area Grouping 11) at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-02-01

The White Wing Scrap Yard, located on the U.S. Department of Energy's Oak Ridge Reservation, served as an aboveground storage and disposal area for contaminated debris and scrap from the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, and the Oak Ridge National laboratory. The site is believed to have been active from the early 1950s until the mid-1960s. A variety of materials were disposed of at the site, including contaminated steel tanks and vehicles. As an interim corrective action, a surface debris removal effort was initiated in November 1993 to reduce the potential threat to human health and the environment from the radionuclide-contaminated debris. Following this removal effort, a geophysical survey will be conducted across the site to locate and determine the lateral extent of buried nonindigenous materials. This survey will provide the data necessary to prepare a map showing areas of conductivity and magnetic intensity that vary from measured background values. These anomalies represent potential buried materials and therefore can be targeted for further evaluation. This work plan outlines the activities necessary to conduct the geophysical survey

Smart grids - French Expertise

International Nuclear Information System (INIS)

2015-11-01

The adaptation of electrical systems is the focus of major work worldwide. Bringing electricity to new territories, modernizing existing electricity grids, implementing energy efficiency policies and deploying renewable energies, developing new uses for electricity, introducing electric vehicles - these are the challenges facing a multitude of regions and countries. Smart Grids are the result of the convergence of electrical systems technologies with information and communications technologies. They play a key role in addressing the above challenges. Smart Grid development is a major priority for both public and private-sector actors in France. The experience of French companies has grown with the current French electricity system, a system that already shows extensive levels of 'intelligence', efficiency and competitiveness. French expertise also leverages substantial competence in terms of 'systems engineering', and can provide a tailored response to meet all sorts of needs. French products and services span all the technical and commercial building blocks that make up the Smart Grid value chain. They address the following issues: Improving the use and valuation of renewable energies and decentralized means of production, by optimizing the balance between generation and consumption. Strengthening the intelligence of the transmission and distribution grids: developing 'Supergrid', digitizing substations in transmission networks, and automating the distribution grids are the focus of a great many projects designed to reinforce the 'self-healing' capacity of the grid. Improving the valuation of decentralized flexibilities: this involves, among others, deploying smart meters, reinforcing active energy efficiency measures, and boosting consumers' contribution to grid balancing, via practices such as demand response which implies the aggregation of flexibility among residential, business, and/or industrial sites. Addressing current technological challenges, in

Power grid complex network evolutions for the smart grid

NARCIS (Netherlands)

Pagani, Giuliano Andrea; Aiello, Marco

2014-01-01

The shift towards an energy grid dominated by prosumers (consumers and producers of energy) will inevitably have repercussions on the electricity distribution infrastructure. Today the grid is a hierarchical one delivering energy from large scale facilities to end-users. Tomorrow it will be a

Circulation in the region of the Reykjanes Ridge in June-July 2015

Science.gov (United States)

Tillys, Petit; Herle, Mercier; Virginie, Thierry

2017-04-01

The Reykjanes Ridge is a major topographic feature of the North-Atlantic Ocean lying south of Iceland that strongly influences the pathways of the upper and lower limbs of the meridional overturning cell. The circulation in the vicinity of the Reykjanes Ridge is anticyclonic and characterized by a southwestward flow (the East Reykjanes Ridge Current, ERRC) along the eastern flank and a northeastward flow (the Irminger Current, IC) along the western flank. Even if it is admitted that the ERRC feeds the IC through a cross-ridge flow, details and magnitude of this circulation remain unclear. In this study, the circulation in the region of the Reykjanes Ridge was investigated based on ADCP and CTDO2 measurements carried out from the R/V Thalassa during the RREX cruise, which provided a snapshot of the water mass distribution and circulation during summer 2015. One hydrographic section followed the top of the Reykjanes Ridge between Iceland and 50˚ N and three other sections were carried out perpendicularly to the ridge at 62˚ N, 58.5˚ N and 56˚ N. Geostrophic transports were estimated by combining ADCP and hydrographic data. Those observations were used to provide an estimate of the circulation around the Ridge and to discuss the meridional evolutions of the ERRC and IC transports along the Ridge and their connection to the cross-Ridge flows. The section along the top of the Reykjanes Ridge allowed us to describe the cross ridge exchanges. A westward flow crossed the Ridge between Iceland and 53˚ N. Its top to bottom integrated transport was estimated at 17.7 Sv. Two main passages were identified for the westward crossing. A first passage is located near 57˚ N (Bight Fracture Zone, BFZ) in agreement with previous studies. More surprisingly, a second passage is located near 59˚ N. The top-to-bottom transports of those two main flows were estimated at 6.5 and 8 Sv respectively. The IC and ERRC top-to-bottom integrated transports were maximum at 58.5˚ N and

Some Improved Classification-Based Ridge Parameter Of Hoerl And ...

African Journals Online (AJOL)

Of Hoerl And Kennard Estimation Techniques. 1Adewale F. Lukmanand 1Kayode Ayinde. 1 Department of Statistics, ... ordinary least square (OLS) in handling it. However, it requires a ridge parameter, K, of which many have ... handle the problem of multicollinearity. They suggested the addition of ridge parameter K to the ...

Surface radiological investigation of Trench 5 in Waste Area Grouping 7 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Goff, D.D.

1991-08-01

A surface radiological investigation of areas encompassing Trench 5 on the Oak Ridge Reservation (ORR) was conducted from May 1990 through November 1990. This survey was led by the author, assisted by various members of the Measurement Applications and Development (MAD) group of the Health and Safety Research Division (HASRD) of Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The purpose of the investigation was to determine the presence, nature, and extent of surface radiological contamination at Trench 5, the Homogeneous Reactor Experiment fuel wells, and surrounding areas. Based on the data obtained in the field, interim corrective measures were recommended to limit human exposure to radioactivity and to minimize insult to the environment. It should be stressed that this project was not intended to be a complete site characterization but rather to be a preliminary investigation into the potential contamination problem that might exist as a result of past operations at Trench 5

Morphotectonic and petrological variations along the southern Central Indian Ridge

Digital Repository Service at National Institute of Oceanography (India)

Mukhopadhyay, R.; Iyer, S.D.; Ray, Dwijesh; Karisiddaiah, S.M.; Drolia, R.K.

above the DM and Enriched Mantle (EM2) end member and resemble a linear mixing with Indian Ocean pelagic sediments (Fig. 4a, b). By contrast, the isotope data of IOTJ-MORB occupy a distinct field in the radiogenic Pb-Pb and Sr-Pb binary plots... EM, Karsten JL, 1995 Ocean-ridge basalts with convergent-margin geochemical affinities from the Chile Ridge. Nature 374:52-57 Klein EM, Langmuir CH, 1987 Global correlations of ocean ridge basalt chemistry with axial depth and crustal chemistry...

Grid interoperability: the interoperations cookbook

Energy Technology Data Exchange (ETDEWEB)

Field, L; Schulz, M [CERN (Switzerland)], E-mail: Laurence.Field@cern.ch, E-mail: Markus.Schulz@cern.ch

2008-07-01

Over recent years a number of grid projects have emerged which have built grid infrastructures that are now the computing backbones for various user communities. A significant number of these communities are limited to one grid infrastructure due to the different middleware and procedures used in each grid. Grid interoperation is trying to bridge these differences and enable virtual organizations to access resources independent of the grid project affiliation. This paper gives an overview of grid interoperation and describes the current methods used to bridge the differences between grids. Actual use cases encountered during the last three years are discussed and the most important interfaces required for interoperability are highlighted. A summary of the standardisation efforts in these areas is given and we argue for moving more aggressively towards standards.

Grid interoperability: the interoperations cookbook

International Nuclear Information System (INIS)

Field, L; Schulz, M

2008-01-01

Over recent years a number of grid projects have emerged which have built grid infrastructures that are now the computing backbones for various user communities. A significant number of these communities are limited to one grid infrastructure due to the different middleware and procedures used in each grid. Grid interoperation is trying to bridge these differences and enable virtual organizations to access resources independent of the grid project affiliation. This paper gives an overview of grid interoperation and describes the current methods used to bridge the differences between grids. Actual use cases encountered during the last three years are discussed and the most important interfaces required for interoperability are highlighted. A summary of the standardisation efforts in these areas is given and we argue for moving more aggressively towards standards

Calculation approaches for grid usage fees to influence the load curve in the distribution grid level

International Nuclear Information System (INIS)

Illing, Bjoern

2014-01-01

Dominated by the energy policy the decentralized German energy market is changing. One mature target of the government is to increase the contribution of renewable generation to the gross electricity consumption. In order to achieve this target disadvantages like an increased need for capacity management occurs. Load reduction and variable grid fees offer the grid operator solutions to realize capacity management by influencing the load profile. The evolution of the current grid fees towards more causality is required to adapt these approaches. Two calculation approaches are developed in this assignment. On the one hand multivariable grid fees keeping the current components demand and energy charge. Additional to the grid costs grid load dependent parameters like the amount of decentralized feed-ins, time and local circumstances as well as grid capacities are considered. On the other hand the grid fee flat-rate which represents a demand based model on a monthly level. Both approaches are designed to meet the criteria for future grid fees. By means of a case study the effects of the grid fees on the load profile at the low voltage grid is simulated. Thereby the consumption is represented by different behaviour models and the results are scaled at the benchmark grid area. The resulting load curve is analyzed concerning the effects of peak load reduction as well as the integration of renewable energy sources. Additionally the combined effect of grid fees and electricity tariffs is evaluated. Finally the work discusses the launching of grid fees in the tense atmosphere of politics, legislation and grid operation. Results of this work are two calculation approaches designed for grid operators to define the grid fees. Multivariable grid fees are based on the current calculation scheme. Hereby demand and energy charges are weighted by time, locational and load related dependencies. The grid fee flat-rate defines a limitation in demand extraction. Different demand levels

Grid Security

CERN Multimedia

CERN. Geneva

2004-01-01

The aim of Grid computing is to enable the easy and open sharing of resources between large and highly distributed communities of scientists and institutes across many independent administrative domains. Convincing site security officers and computer centre managers to allow this to happen in view of today's ever-increasing Internet security problems is a major challenge. Convincing users and application developers to take security seriously is equally difficult. This paper will describe the main Grid security issues, both in terms of technology and policy, that have been tackled over recent years in LCG and related Grid projects. Achievements to date will be described and opportunities for future improvements will be addressed.

Testing models for the formation of the equatorial ridge on Iapetus via crater counting

Science.gov (United States)

Damptz, Amanda L.; Dombard, Andrew J.; Kirchoff, Michelle R.

2018-03-01

Iapetus's equatorial ridge, visible in global views of the moon, is unique in the Solar System. The formation of this feature is likely attributed to a key event in the evolution of Iapetus, and various models have been proposed as the source of the ridge. By surveying imagery from the Cassini and Voyager missions, this study aims to compile a database of the impact crater population on and around Iapetus's equatorial ridge, assess the relative age of the ridge from differences in cratering between on ridge and off ridge, and test the various models of ridge formation. This work presents a database that contains 7748 craters ranging from 0.83 km to 591 km in diameter. The database includes the study area in which the crater is located, the latitude and longitude of the crater, the major and minor axis lengths, and the azimuthal angle of orientation of the major axis. Analysis of crater orientation over the entire study area reveals that there is no preference for long-axis orientation, particularly in the area with the highest resolution. Comparison of the crater size-frequency distributions show that the crater distribution on the ridge appears to be depleted in craters larger than 16 km with an abruptly enhanced crater population less than 16 km in diameter up to saturation. One possible interpretation is that the ridge is a relatively younger surface with an enhanced small impactor population. Finally, the compiled results are used to examine each ridge formation hypothesis. Based on these results, a model of ridge formation via a tidally disrupted sub-satellite appears most consistent with our interpretation of a younger ridge with an enhanced small impactor population.

Emissions & Generation Resource Integrated Database (eGRID), eGRID2012

Data.gov (United States)

U.S. Environmental Protection Agency — The Emissions emissions rates; net generation; resource mix; and many other attributes. eGRID2012 Version 1.0 is the eighth edition of eGRID, which contains the...

Seismic imaging of the Formosa Ridge cold seep site offshore of southwestern Taiwan

Science.gov (United States)

Hsu, Ho-Han; Liu, Char-Shine; Morita, Sumito; Tu, Shu-Lin; Lin, Saulwood; Machiyama, Hideaki; Azuma, Wataru; Ku, Chia-Yen; Chen, Song-Chuen

2017-12-01

Multi-scale reflection seismic data, from deep-penetration to high-resolution, have been analyzed and integrated with near-surface geophysical and geochemical data to investigate the structures and gas hydrate system of the Formosa Ridge offshore of southwestern Taiwan. In 2007, dense and large chemosynthetic communities were discovered on top of the Formosa Ridge at water depth of 1125 m by the ROV Hyper-Dolphin. A continuous and strong BSR has been observed on seismic profiles from 300 to 500 ms two-way-travel-time below the seafloor of this ridge. Sedimentary strata of the Formosa Ridge are generally flat lying which suggests that this ridge was formed by submarine erosion processes of down-slope canyon development. In addition, some sediment waves and mass wasting features are present on the ridge. Beneath the cold seep site, a vertical blanking zone, or seismic chimney, is clearly observed on seismic profiles, and it is interpreted to be a fluid conduit. A thick low velocity zone beneath BSR suggests the presence of a gas reservoir there. This "gas reservoir" is shallower than the surrounding canyon floors along the ridge; therefore as warm methane-rich fluids inside the ridge migrate upward, sulfate carried by cold sea water can flow into the fluid system from both flanks of the ridge. This process may drive a fluid circulation system and the active cold seep site which emits both hydrogen sulfide and methane to feed the chemosynthetic communities.

Global Models of Ridge-Push Force, Geoid, and Lithospheric Strength of Oceanic plates

Science.gov (United States)

Mahatsente, Rezene

2017-12-01

An understanding of the transmission of ridge-push related stresses in the interior of oceanic plates is important because ridge-push force is one of the principal forces driving plate motion. Here, I assess the transmission of ridge-push related stresses in oceanic plates by comparing the magnitude of the ridge-push force to the integrated strength of oceanic plates. The strength is determined based on plate cooling and rheological models. The strength analysis includes low-temperature plasticity (LTP) in the upper mantle and assumes a range of possible tectonic conditions and rheology in the plates. The ridge-push force has been derived from the thermal state of oceanic lithosphere, seafloor depth and crustal age data. The results of modeling show that the transmission of ridge-push related stresses in oceanic plates mainly depends on rheology and predominant tectonic conditions. If a lithosphere has dry rheology, the estimated strength is higher than the ridge-push force at all ages for compressional tectonics and at old ages (>75 Ma) for extension. Therefore, under such conditions, oceanic plates may not respond to ridge-push force by intraplate deformation. Instead, the plates may transmit the ridge-push related stress in their interior. For a wet rheology, however, the strength of young lithosphere (stress may dissipate in the interior of oceanic plates and diffuses by intraplate deformation. The state of stress within a plate depends on the balance of far-field and intraplate forces.

THE STATISTICAL MODEL OF PRESSURE RIDGE MORPHOMETRY ON THE NORTHEAST SHELF OF SAKHALIN ISLAND

Directory of Open Access Journals (Sweden)

E. U. Mironov

2012-01-01

Full Text Available The work presents characteristics on geometry and inner structure of ice ridges investigated at offshore the northeast coast of SakhalinIsland. A formula was obtained which allows one to calculate the ice ridge keel depth by the height of its sail. Plots of the probability distribution density for ice ridge characteristics are given. A model of morphometry of a mean statistical ice ridge was constructed, and its mass is determined. Factors influencing the hydrostatic ice ridge equilibrium are considered.

Active spreading processes at ultraslow mid-ocean ridges: The 1999-2001 seismo-volcanic episode at 85°E Gakkel ridge, Arctic Ocean

Science.gov (United States)

Schlindwein, Vera; Riedel, Carsten; Korger, Edith; Läderach, Christine

2010-05-01

The rate of magma and crustal production at mid-ocean ridges is thought to decrease with decreasing spreading rate. At ultraslow spreading rates below 10-20 mm/y full rate, heat loss by conduction greatly reduces melt production with less melt produced at increasingly greater depths. Gakkel Ridge, the actively spreading mid-ocean ridge in the Arctic Ocean, opens at rates of 14 mm/y in the west decreasing to less than 6 mm/y at its eastern termination and demonstrates that magma production is not only a function of spreading rate. Whereas amagmatic spreading takes place at rates of about 12-10 mm/y, focussed melt production occurs at even lower spreading rates in long-lived discrete volcanic centres. One such centre is the 85°E volcanic complex at eastern Gakkel ridge where in 1999 a teleseismically recorded earthquake swarm consisting of more than 250 earthquakes over 9 months signalled the onset of an active spreading episode. The earthquake swarm is believed to be associated with volcanic activity although no concurrent lava effusion was found. We analysed the teleseismic earthquake swarm together with visual observation and microseismic data recorded at this site in 2001 and 2007 and noted the following characteristics which may be indicative for volcanic spreading events at the still poorly explored ultraslow spreading ridges: - unusual duration: The 1999 earthquake swarm lasted over 9 months rather than a few weeks as observed on faster spreading ridges. In addition, in 2001 seismoacoustic sounds which we interpret as gas discharge in Strombolian eruptions and a giant event plume maintained over more than one year indicate waxing and waning volcanic activity since 1999. - unusual strength: The earthquake swarm was detected at teleseismic distances of more than 1000 km and included 11 events with a magnitude >5. No other confirmed mid-ocean ridge eruption released a comparable seismic moment. Rather than focussing in a narrow area or showing pronounced

LHC computing grid

International Nuclear Information System (INIS)

Novaes, Sergio

2011-01-01

Full text: We give an overview of the grid computing initiatives in the Americas. High-Energy Physics has played a very important role in the development of grid computing in the world and in Latin America it has not been different. Lately, the grid concept has expanded its reach across all branches of e-Science, and we have witnessed the birth of the first nationwide infrastructures and its use in the private sector. (author)

High density grids

Energy Technology Data Exchange (ETDEWEB)

Cohen, Aina E.; Baxter, Elizabeth L.

2018-01-16

An X-ray data collection grid device is provided that includes a magnetic base that is compatible with robotic sample mounting systems used at synchrotron beamlines, a grid element fixedly attached to the magnetic base, where the grid element includes at least one sealable sample window disposed through a planar synchrotron-compatible material, where the planar synchrotron-compatible material includes at least one automated X-ray positioning and fluid handling robot fiducial mark.

Comparison tomography relocation hypocenter grid search and guided grid search method in Java island

International Nuclear Information System (INIS)

Nurdian, S. W.; Adu, N.; Palupi, I. R.; Raharjo, W.

2016-01-01

The main data in this research is earthquake data recorded from 1952 to 2012 with 9162 P wave and 2426 events are recorded by 30 stations located around Java island. Relocation hypocenter processed using grid search and guidded grid search method. Then the result of relocation hypocenter become input for tomography pseudo bending inversion process. It can be used to identification the velocity distribution in subsurface. The result of relocation hypocenter by grid search and guided grid search method after tomography process shown in locally and globally. In locally area grid search method result is better than guided grid search according to geological reseach area. But in globally area the result of guided grid search method is better for a broad area because the velocity variation is more diverse than the other one and in accordance with local geological research conditions. (paper)

Hot subduction: Magmatism along the Hunter Ridge, SW Pacific

International Nuclear Information System (INIS)

Crawford, A.J.; Verbeeten, A.; Danyushevsky, L.V.; Sigurdsson, I.A.; Maillet, P.; Monzier, M.

1997-01-01

The Hunter 'fracture zone' is generally regarded as a transform plate boundary linking the oppositely dipping Tongan and Vanuatu subduction systems. Dredging along the Hunter Ridge and sampling of its northernmost extent, exposed as the island of Kadavu in Fiji, has yielded a diversity of magmatic suites, including arc tholeiites and high-Ca boninites, high-Mg lavas with some affinities to boninites and some affinities to adakites, and true adakitic lavas associated with remarkable low-Fe, high-Na basalts with 8-16 ppm Nb (herein high-Nb basalts). Lavas which show clear evidence of slab melt involvement in their petrogenesis occur at either end of the Hunter Ridge, whereas the arc tholeiites and high-Ca boninites appear to be restricted to the south central part of the ridge. Mineralogical and whole rock geochemical data for each of these suites are summarized, and a tectono-magmatic model for their genesis and distribution is suggested. Trace element features and radiogenic isotope data for the Hunter Ridge lavas indicate compositions analogue to Pacific MORB-like mantle

Crustal structure and tectonics of the Ninetyeast Ridge from seismic and gravity studies

Digital Repository Service at National Institute of Oceanography (India)

Krishna, K.S.; Neprochnov, Y.P.; Rao, D.G.; Grinko, B.N.

Seismic reflection and refraction, gravity, and bathymetric data across and along the central part of the Ninetyeast Ridge were analyzed to determine the crustal structure of the ridge and to understand its tectonics. The ridge in the study area...

Framing the grid: effect of boundaries on grid cells and navigation.

Science.gov (United States)

Krupic, Julija; Bauza, Marius; Burton, Stephen; O'Keefe, John

2016-11-15

Cells in the mammalian hippocampal formation subserve neuronal representations of environmental location and support navigation in familiar environments. Grid cells constitute one of the main cell types in the hippocampal formation and are widely believed to represent a universal metric of space independent of external stimuli. Recent evidence showing that grid symmetry is distorted in non-symmetrical environments suggests that a re-examination of this hypothesis is warranted. In this review we will discuss behavioural and physiological evidence for how environmental shape and in particular enclosure boundaries influence grid cell firing properties. We propose that grid cells encode the geometric layout of enclosures. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

The open science grid

International Nuclear Information System (INIS)

Pordes, R.

2004-01-01

The U.S. LHC Tier-1 and Tier-2 laboratories and universities are developing production Grids to support LHC applications running across a worldwide Grid computing system. Together with partners in computer science, physics grid projects and active experiments, we will build a common national production grid infrastructure which is open in its architecture, implementation and use. The Open Science Grid (OSG) model builds upon the successful approach of last year's joint Grid2003 project. The Grid3 shared infrastructure has for over eight months provided significant computational resources and throughput to a range of applications, including ATLAS and CMS data challenges, SDSS, LIGO, and biology analyses, and computer science demonstrators and experiments. To move towards LHC-scale data management, access and analysis capabilities, we must increase the scale, services, and sustainability of the current infrastructure by an order of magnitude or more. Thus, we must achieve a significant upgrade in its functionalities and technologies. The initial OSG partners will build upon a fully usable, sustainable and robust grid. Initial partners include the US LHC collaborations, DOE and NSF Laboratories and Universities and Trillium Grid projects. The approach is to federate with other application communities in the U.S. to build a shared infrastructure open to other sciences and capable of being modified and improved to respond to needs of other applications, including CDF, D0, BaBar, and RHIC experiments. We describe the application-driven, engineered services of the OSG, short term plans and status, and the roadmap for a consortium, its partnerships and national focus

Porting of Scientific Applications to Grid Computing on GridWay

Directory of Open Access Journals (Sweden)

J. Herrera

2005-01-01

Full Text Available The expansion and adoption of Grid technologies is prevented by the lack of a standard programming paradigm to port existing applications among different environments. The Distributed Resource Management Application API has been proposed to aid the rapid development and distribution of these applications across different Distributed Resource Management Systems. In this paper we describe an implementation of the DRMAA standard on a Globus-based testbed, and show its suitability to express typical scientific applications, like High-Throughput and Master-Worker applications. The DRMAA routines are supported by the functionality offered by the GridWay2 framework, which provides the runtime mechanisms needed for transparently executing jobs on a dynamic Grid environment based on Globus. As cases of study, we consider the implementation with DRMAA of a bioinformatics application, a genetic algorithm and the NAS Grid Benchmarks.

Holifield Heavy-Ion Research Facility at Oak Ridge

International Nuclear Information System (INIS)

Jones, C.M.

1977-01-01

A new heavy-ion accelerator facility is now under construction at the Oak Ridge National Laboratory. A brief description of the scope and schedule of this project is given, and the new large tandem accelerator, which will be a major element of the facility is discussed in some detail. Several studies which have been made or are in progress in Oak Ridge in preparation for operation of the tandem accelerator are briefly described

Mid Ocean Ridge Processes at Very Low Melt Supply : Submersible Exploration of Smooth Ultramafic Seafloor at the Southwest Indian Ridge, 64 degree E

Science.gov (United States)

Cannat, M.; Agrinier, P.; Bickert, M.; Brunelli, D.; Hamelin, C.; Lecoeuvre, A.; Lie Onstad, S.; Maia, M.; Prampolini, M.; Rouméjon, S.; Vitale Brovarone, A.; Besançon, S.; Assaoui, E. M.

2017-12-01

Mid-ocean ridges are the Earth's most extensive and active volcanic chains. They are also, particularly at slow spreading rates, rift zones, where plate divergence is in part accommodated by faults. Large offset normal faults, also called detachments, are characteristic of slow-spreading ridges, where they account for the widespread emplacement of mantle-derived rocks at the seafloor. In most cases, these detachments occur together with ridge magmatism, with melt injection and faulting interacting to shape the newly formed oceanic lithosphere. Here, we seek to better understand these interactions and their effects on oceanic accretion by studying the end-member case of a ridge where magmatism is locally almost absent. The portion of the Southwest Indian ridge we are studying has an overal low melt supply, focused to discrete axial volcanoes, leaving almost zero melt to intervening sections of the axial valley. One of these nearly amagmatic section of the ridge, located at 64°E, has been the focus of several past cruises (sampling, mapping and seismic experiments). Here we report on the most recent cruise to the area (RV Pourquoi Pas? with ROV Victor; dec-jan 2017), during which we performed high resolution mapping, submersible exploration and sampling of the ultramafic seafloor and of sparse volcanic formations. Our findings are consistent with the flip-flop detachment hypothesis proposed for this area by Sauter et al. (Nature Geosciences, 2013; ultramafic seafloor forming in the footwall of successive detachment faults, each cutting into the footwall of the previous fault, with an opposite polarity). Our observations also document the extent and geometry of deformation in the footwall of a young axial detachment, the role of mass-wasting for the evolution of this detachment, and provide spectacular evidence for serpentinization-related hydrothermal circulation and for spatial links between faults and volcanic eruptions.

FermiGrid - experience and future plans

International Nuclear Information System (INIS)

Chadwick, K.; Berman, E.; Canal, P.; Hesselroth, T.; Garzoglio, G.; Levshina, T.; Sergeev, V.; Sfiligoi, I.; Timm, S.; Yocum, D.

2007-01-01

Fermilab supports a scientific program that includes experiments and scientists located across the globe. In order to better serve this community, Fermilab has placed its production computer resources in a Campus Grid infrastructure called 'FermiGrid'. The FermiGrid infrastructure allows the large experiments at Fermilab to have priority access to their own resources, enables sharing of these resources in an opportunistic fashion, and movement of work (jobs, data) between the Campus Grid and National Grids such as Open Science Grid and the WLCG. FermiGrid resources support multiple Virtual Organizations (VOs), including VOs from the Open Science Grid (OSG), EGEE and the Worldwide LHC Computing Grid Collaboration (WLCG). Fermilab also makes leading contributions to the Open Science Grid in the areas of accounting, batch computing, grid security, job management, resource selection, site infrastructure, storage management, and VO services. Through the FermiGrid interfaces, authenticated and authorized VOs and individuals may access our core grid services, the 10,000+ Fermilab resident CPUs, near-petabyte (including CMS) online disk pools and the multi-petabyte Fermilab Mass Storage System. These core grid services include a site wide Globus gatekeeper, VO management services for several VOs, Fermilab site authorization services, grid user mapping services, as well as job accounting and monitoring, resource selection and data movement services. Access to these services is via standard and well-supported grid interfaces. We will report on the user experience of using the FermiGrid campus infrastructure interfaced to a national cyberinfrastructure--the successes and the problems

Smart grid in China

DEFF Research Database (Denmark)

Sommer, Simon; Ma, Zheng; Jørgensen, Bo Nørregaard

2015-01-01

China is planning to transform its traditional power grid in favour of a smart grid, since it allows a more economically efficient and a more environmentally friendly transmission and distribution of electricity. Thus, a nationwide smart grid is likely to save tremendous amounts of resources...

An aerial radiological survey of the White Oak Creek Floodplain, Oak Ridge Reservation, Oak Ridge, Tennessee: Date of survey: September-October 1986

International Nuclear Information System (INIS)

Fritzsche, A.E.

1987-06-01

An aerial radiological survey was conducted over the White Oak Creek Floodplain of the Oak Ridge Reservation during the period 30 September through 3 October 1986. The survey was performed at the request of the United States Department of Energy (DOE), Oak Ridge Operations Office, by EG and G Energy Measurements, Inc. (EG and G/EM), a contractor of the DOE. The survey results will be utilized in support of the Remedial Action Program being conducted at the site by Martin Marietta Energy Systems, Inc., operator of the Oak Ridge National Laboratory (ORNL). A flight line spacing of 37 meters (120 feet) and a survey altitude of 46 meters (150 feet) yielded the maximum data density and sensitivity achievable by the aerial system, which was greater than that achieved from prior surveys of the entire Oak Ridge Reservation. Isopleth maps of Cs-137, Co-60, Ti-208 implied concentrations, and exposure rates provided an estimate of the location and magnitude of the man-made activity. These maps, overlaid on a current photograph of the area, combine to yield a view of the radiological condition of the White Oak Creek Floodplain. 5 refs., 40 figs., 3 tabs

The Northern Central Indian Ridge: Geology and tectonics of fracture zones-dominated spreading ridge segments

Digital Repository Service at National Institute of Oceanography (India)

Drolia, R.K.; Iyer, S.D.; Chakraborty, B.; Kodagali, V.N.; Ray, Dwijesh; Misra, S.; Andrade, R.; Sarma, K.V.L.N.S.; Rajasekhar, R.P.; Mukhopadhyay, R.

Multi-beam and single-beam bathymetric, gravity and magnetic data, across seven ridge segments (length varying between 37 and 84 km), offset by six transform discontinuities (ranging in dislocation length between 48 and 344 km) of the Northern...

Results of 1995 characterization of Gunite and Associated Tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-01

This technical memorandum (TM) documents the 1995 characterization of eight underground radioactive waste tanks at Oak Ridge National Laboratory (ORNL). These tanks belong to the Gunite and Associated Tanks (GAAT) operable unit, and the characterization is part of the ongoing GAAT remedial investigation/feasibility study (RI/FS) process. This TM reports both field observations and analytical results; analytical results are also available from the Oak Ridge Environmental Information System (OREIS) data base under the project name GAAT (PROJ-NAME = GAAT). This characterization effort (Phase II) was a follow-up to the {open_quotes}Phase I{close_quotes} sampling campaign reported in Results of Fall 1994 Sampling of Gunite and Associated Tanks at the Oak Ridge National Laboratory, Oak Ridge, Tennessee, ORNL/ER/Sub/87-99053/74, June 1995. The information contained here should be used in conjunction with that in the previous TM. The sampling plan is documented in ORNL Inactive Waste Tanks Sampling and Analysis Plan, ORNL/RAP/LTR-88/24, dated April 1988, as amended by Addendum 1, Revision 2: ORNL Inactive Tanks Sampling and Analysis Plan, DOE/OR/02-1354&D2, dated February 1995. Field team instructions are found in ORNL RI/FS Project Field Work Guides 01-WG-20, Field Work Guide for Sampling of Gunite and Associated Tanks, and 01-WG-21, Field Work Guide for Tank Characterization System Operations at ORNL. The field effort was conducted under the programmatic and procedural umbrella of the ORNL RI/FS Program, and the analysis was in accordance with ORNL Chemical and Analytical Sciences Division (CASD) procedures. The characterization campaign is intended to provide data for criticality safety, engineering design, and waste management as they apply to the GAAT treatability study and remediation. The Department of Energy (DOE) Carlsbad office was interested in results of this sampling campaign and provided funding for certain additional sample collection and analysis.

Decentral Smart Grid Control

Science.gov (United States)

Schäfer, Benjamin; Matthiae, Moritz; Timme, Marc; Witthaut, Dirk

2015-01-01

Stable operation of complex flow and transportation networks requires balanced supply and demand. For the operation of electric power grids—due to their increasing fraction of renewable energy sources—a pressing challenge is to fit the fluctuations in decentralized supply to the distributed and temporally varying demands. To achieve this goal, common smart grid concepts suggest to collect consumer demand data, centrally evaluate them given current supply and send price information back to customers for them to decide about usage. Besides restrictions regarding cyber security, privacy protection and large required investments, it remains unclear how such central smart grid options guarantee overall stability. Here we propose a Decentral Smart Grid Control, where the price is directly linked to the local grid frequency at each customer. The grid frequency provides all necessary information about the current power balance such that it is sufficient to match supply and demand without the need for a centralized IT infrastructure. We analyze the performance and the dynamical stability of the power grid with such a control system. Our results suggest that the proposed Decentral Smart Grid Control is feasible independent of effective measurement delays, if frequencies are averaged over sufficiently large time intervals.

Decentral Smart Grid Control

International Nuclear Information System (INIS)

Schäfer, Benjamin; Matthiae, Moritz; Timme, Marc; Witthaut, Dirk

2015-01-01

Stable operation of complex flow and transportation networks requires balanced supply and demand. For the operation of electric power grids—due to their increasing fraction of renewable energy sources—a pressing challenge is to fit the fluctuations in decentralized supply to the distributed and temporally varying demands. To achieve this goal, common smart grid concepts suggest to collect consumer demand data, centrally evaluate them given current supply and send price information back to customers for them to decide about usage. Besides restrictions regarding cyber security, privacy protection and large required investments, it remains unclear how such central smart grid options guarantee overall stability. Here we propose a Decentral Smart Grid Control, where the price is directly linked to the local grid frequency at each customer. The grid frequency provides all necessary information about the current power balance such that it is sufficient to match supply and demand without the need for a centralized IT infrastructure. We analyze the performance and the dynamical stability of the power grid with such a control system. Our results suggest that the proposed Decentral Smart Grid Control is feasible independent of effective measurement delays, if frequencies are averaged over sufficiently large time intervals. (paper)

A Grid Voltage Measurement Method for Wind Power Systems during Grid Fault Conditions

OpenAIRE

Yoo, Cheol-Hee; Chung, Il-Yop; Yoo, Hyun-Jae; Hong, Sung-Soo

2014-01-01

Grid codes in many countries require low-voltage ride-through (LVRT) capability to maintain power system stability and reliability during grid fault conditions. To meet the LVRT requirement, wind power systems must stay connected to the grid and also supply reactive currents to the grid to support the recovery from fault voltages. This paper presents a new fault detection method and inverter control scheme to improve the LVRT capability for full-scale permanent magnet synchronous generator (P...

Benchmarking of Grid Fault Modes in Single-Phase Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

2013-01-01

Pushed by the booming installations of singlephase photovoltaic (PV) systems, the grid demands regarding the integration of PV systems are expected to be modified. Hence, the future PV systems should become more active with functionalities of Low Voltage Ride-Through (LVRT) and grid support...... phase systems under grid faults. The intent of this paper is to present a benchmarking of grid fault modes that might come in future single-phase PV systems. In order to map future challenges, the relevant synchronization and control strategies are discussed. Some faulty modes are studied experimentally...... and provided at the end of this paper. It is concluded that there are extensive control possibilities in single-phase PV systems under grid faults. The Second Order General Integral based PLL technique might be the most promising candidate for future single-phase PV systems because of its fast adaptive...

Determining Maximum Photovoltaic Penetration in a Distribution Grid considering Grid Operation Limits

DEFF Research Database (Denmark)

Kordheili, Reza Ahmadi; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

2014-01-01

High penetration of photovoltaic panels in distribution grid can bring the grid to its operation limits. The main focus of the paper is to determine maximum photovoltaic penetration level in the grid. Three main criteria were investigated for determining maximum penetration level of PV panels...... for this grid: even distribution of PV panels, aggregation of panels at the beginning of each feeder, and aggregation of panels at the end of each feeder. Load modeling is done using Velander formula. Since PV generation is highest in the summer due to irradiation, a summer day was chosen to determine maximum......; maximum voltage deviation of customers, cables current limits, and transformer nominal value. Voltage deviation of different buses was investigated for different penetration levels. The proposed model was simulated on a Danish distribution grid. Three different PV location scenarios were investigated...

Site descriptions of environmental restoration units at the Oak Ridge K-25 Site, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Goddard, P.L.; Legeay, A.J.; Pesce, D.S.; Stanley, A.M.

1995-11-01

This report, Site Descriptions of Environmental Restoration Units at the Oak Ridge K-25 Site, Oak Ridge, Tennessee, is being prepared to assimilate information on sites included in the Environmental Restoration (ER) Program of the K-25 Site, one of three major installations on the Oak Ridge Reservation (ORR) built during World War III as part of the Manhattan Project. The information included in this report will be used to establish program priorities so that resources allotted to the K-25 ER Program can be best used to decrease any risk to humans or the environment, and to determine the sequence in which any remedial activities should be conducted. This document will be updated periodically in both paper and Internet versions. Units within this report are described in individual data sheets arranged alphanumerically. Each data sheet includes entries on project status, unit location, dimensions and capacity, dates operated, present function, lifecycle operation, waste characteristics, site status, media of concern, comments, and references. Each data sheet is accompanied by a photograph of the unit, and each unit is located on one of 13 area maps. These areas, along with the sub-area, unit, and sub-unit breakdowns within them, are outlined in Appendix A. Appendix B is a summary of information on remote aerial sensing and its applicability to the ER program

Site descriptions of environmental restoration units at the Oak Ridge K-25 Site, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Goddard, P.L.; Legeay, A.J.; Pesce, D.S.; Stanley, A.M.

1995-11-01

This report, Site Descriptions of Environmental Restoration Units at the Oak Ridge K-25 Site, Oak Ridge, Tennessee, is being prepared to assimilate information on sites included in the Environmental Restoration (ER) Program of the K-25 Site, one of three major installations on the Oak Ridge Reservation (ORR) built during World War III as part of the Manhattan Project. The information included in this report will be used to establish program priorities so that resources allotted to the K-25 ER Program can be best used to decrease any risk to humans or the environment, and to determine the sequence in which any remedial activities should be conducted. This document will be updated periodically in both paper and Internet versions. Units within this report are described in individual data sheets arranged alphanumerically. Each data sheet includes entries on project status, unit location, dimensions and capacity, dates operated, present function, lifecycle operation, waste characteristics, site status, media of concern, comments, and references. Each data sheet is accompanied by a photograph of the unit, and each unit is located on one of 13 area maps. These areas, along with the sub-area, unit, and sub-unit breakdowns within them, are outlined in Appendix A. Appendix B is a summary of information on remote aerial sensing and its applicability to the ER program.

Study of the integration of distributed generation systems in the grid: application in micro-grids

International Nuclear Information System (INIS)

Gaztanaga Arantzamendi, H.

2006-12-01

The present PhD deals with an original micro-grid concept and its application as a Renewable Energy Source's (RES) grid integration scheme. This micro-grid is composed of RES generators as well as support systems that incorporate additional functionalities in order to improve RES integration into the grid. According to this concept, two practical micro-grid applications have been studied in detail: a residential micro-grid and a wind farm supported by DFACTS systems (STATCOM and DVR). In both applications, the control structures which are implemented at different levels and applied to the different micro-grid elements have been developed, analyzed by means of off-line simulations and finally validated in real-time conditions with physical reduced-scale prototypes. (author)

Source document for waste area groupings at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Osborne, P.L.; Kuhaida, A.J., Jr.

1996-09-01

This document serves as a source document for Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and other types of documents developed for and pertaining to Environmental Restoration (ER) Program activities at Oak Ridge National Laboratory (ORNL). It contains descriptions of the (1) regulatory requirements for the ORR ER Program, (2) Oak Ridge Reservation (ORR) ER Program, (3) ORNL site history and characterization, and (4) history and characterization of Waste Area Groupings (WAGS) 1-20. This document was created to save time, effort, and money for persons and organizations drafting documents for the ER Program and to improve consistency in the documents prepared for the program. By eliminating the repetitious use of selected information about the program, this document will help reduce the time and costs associated with producing program documents. By serving as a benchmark for selected information about the ER Program, this reference will help ensure that information presented in future documents is accurate and complete

Oak Ridge Health Studies phase 1 report, Volume 1: Oak Ridge Phase 1 overview

International Nuclear Information System (INIS)

Yarbrough, M.I.; Van Cleave, M.L.; Turri, P.; Daniel, J.

1993-09-01

In July 1991, the State of Tennessee initiated the Health Studies Agreement with the United States Department of Energy to carry out independent studies of possible adverse health effects in people living in the vicinity of the Oak Ridge Reservation. The health studies focus on those effects that could have resulted or could result from exposures to chemicals and radioactivity released at the Reservation since 1942. The major focus of the first phase was to complete a Dose Reconstruction Feasibility Study. This study was designed to find out if enough data exist about chemical and radionuclide releases from the Oak Ridge Reservation to conduct a second phase. The second phase will lead to estimates of the actual amounts or the ''doses'' of various contaminants received by people as a result of off-site releases. Once the doses of various contaminants have been estimated, scientists and physicians will be better able to evaluate whether adverse health effects could have resulted from the releases

Oak Ridge Health Studies phase 1 report, Volume 1: Oak Ridge Phase 1 overview

Energy Technology Data Exchange (ETDEWEB)

Yarbrough, M.I.; Van Cleave, M.L.; Turri, P.; Daniel, J.

1993-09-01

In July 1991, the State of Tennessee initiated the Health Studies Agreement with the United States Department of Energy to carry out independent studies of possible adverse health effects in people living in the vicinity of the Oak Ridge Reservation. The health studies focus on those effects that could have resulted or could result from exposures to chemicals and radioactivity released at the Reservation since 1942. The major focus of the first phase was to complete a Dose Reconstruction Feasibility Study. This study was designed to find out if enough data exist about chemical and radionuclide releases from the Oak Ridge Reservation to conduct a second phase. The second phase will lead to estimates of the actual amounts or the ``doses`` of various contaminants received by people as a result of off-site releases. Once the doses of various contaminants have been estimated, scientists and physicians will be better able to evaluate whether adverse health effects could have resulted from the releases.

FermiGrid-experience and future plans

International Nuclear Information System (INIS)

Chadwick, K; Berman, E; Canal, P; Hesselroth, T; Garzoglio, G; Levshina, T; Sergeev, V; Sfiligoi, I; Sharma, N; Timm, S; Yocum, D R

2008-01-01

Fermilab supports a scientific program that includes experiments and scientists located across the globe. In order to better serve this community, Fermilab has placed its production computer resources in a Campus Grid infrastructure called 'FermiGrid'. The FermiGrid infrastructure allows the large experiments at Fermilab to have priority access to their own resources, enables sharing of these resources in an opportunistic fashion, and movement of work (jobs, data) between the Campus Grid and National Grids such as Open Science Grid (OSG) and the Worldwide LHC Computing Grid Collaboration (WLCG). FermiGrid resources support multiple Virtual Organizations (VOs), including VOs from the OSG, EGEE, and the WLCG. Fermilab also makes leading contributions to the Open Science Grid in the areas of accounting, batch computing, grid security, job management, resource selection, site infrastructure, storage management, and VO services. Through the FermiGrid interfaces, authenticated and authorized VOs and individuals may access our core grid services, the 10,000+ Fermilab resident CPUs, near-petabyte (including CMS) online disk pools and the multi-petabyte Fermilab Mass Storage System. These core grid services include a site wide Globus gatekeeper, VO management services for several VOs, Fermilab site authorization services, grid user mapping services, as well as job accounting and monitoring, resource selection and data movement services. Access to these services is via standard and well-supported grid interfaces. We will report on the user experience of using the FermiGrid campus infrastructure interfaced to a national cyberinfrastructure - the successes and the problems

Oak Ridge Reservation Physical Characteristics and Natural Resources

Energy Technology Data Exchange (ETDEWEB)

Parr, P.D.; Hughes, J.F.

2006-09-19

The topography, geology, hydrology, vegetation, and wildlife of the Oak Ridge Reservation (ORR) provide a complex and intricate array of resources that directly impact land stewardship and use decisions (Fig. 1). The purpose of this document is to consolidate general information regarding the natural resources and physical characteristics of the ORR. The ORR, encompassing 33,114 acres (13,401 ha) of federally owned land and three Department of Energy (DOE) installations, is located in Roane and Anderson Counties in east Tennessee, mostly within the corporate limits of the city of Oak Ridge and southwest of the population center of Oak Ridge. The ORR is bordered on the north and east by the population center of the city of Oak Ridge and on the south and west by the Clinch River/Melton Hill Lake impoundment. All areas of the ORR are relatively pristine when compared with the surrounding region, especially in the Valley and Ridge Physiographic Province (Fig. 2). From the air, the ORR is clearly a large and nearly continuous island of forest within a landscape that is fragmented by urban development and agriculture. Satellite imagery from 2006 was used to develop a land-use/land-cover cover map of the ORR and surrounding lands (Fig. 3). Following the acquisition of the land comprising the ORR in the early 1940s, much of the Reservation served as a buffer for the three primary facilities: the X-10 nuclear research facility (now known as the Oak Ridge National Laboratory [ORNL]), the first uranium enrichment facility or Y-12 (now known as the Y-12 National Security Complex [Y-12 Complex]), and a gaseous diffusion enrichment facility (now known as the East Tennessee Technology Park [ETTP]). Over the past 60 years, this relatively undisturbed area has evolved into a rich and diverse eastern deciduous forest ecosystem of streams and reservoirs, hardwood forests, and extensive upland mixed forests. The combination of a large land area with complex physical characteristics

Oak Ridge Y-12 Plant groundwater protection program management plan

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-06-01

The Oak Ridge Y- 1 2 Plant (Y-12 Plant) is owned by the United States Department of Energy (DOE) and managed by Lockheed Martin Energy Systems, Inc. (Energy Systems) under contract No. DE-AC05-84OR21400. The Y-12 Plant Groundwater Protection Program (GWPP), which was initiated in 1975, provides for the protection of groundwater resources consistent with Federal, State, and local regulations, and in accordance with DOE orders and Energy Systems policies and procedures. The Y-12 Plant is located in Anderson County, Tennessee, and is within the corporate limits of the City of Oak Ridge. The Y-12 Plant is one of three major DOE complexes that comprise the 37,000-acre Oak Ridge Reservation (ORR) located in Anderson and Roane counties. The Y-12 Plant is located in Bear Creek Valley at an elevation of about 950 feet (ft) above sea level. Bear Creek Valley is bounded on the northwest and southeast, and is isolated from populated areas of Oak Ridge, by parallel ridges that rise about 300 ft above the valley floor. The Y-12 Plant and its fenced buffer area are about 0.6 mile wide by 3.2 miles long and cover approximately 4,900 acres. The main industrialized section encompasses approximately 800 acres.

Oak Ridge Y-12 Plant groundwater protection program management plan

International Nuclear Information System (INIS)

1996-06-01

The Oak Ridge Y- 1 2 Plant (Y-12 Plant) is owned by the United States Department of Energy (DOE) and managed by Lockheed Martin Energy Systems, Inc. (Energy Systems) under contract No. DE-AC05-84OR21400. The Y-12 Plant Groundwater Protection Program (GWPP), which was initiated in 1975, provides for the protection of groundwater resources consistent with Federal, State, and local regulations, and in accordance with DOE orders and Energy Systems policies and procedures. The Y-12 Plant is located in Anderson County, Tennessee, and is within the corporate limits of the City of Oak Ridge. The Y-12 Plant is one of three major DOE complexes that comprise the 37,000-acre Oak Ridge Reservation (ORR) located in Anderson and Roane counties. The Y-12 Plant is located in Bear Creek Valley at an elevation of about 950 feet (ft) above sea level. Bear Creek Valley is bounded on the northwest and southeast, and is isolated from populated areas of Oak Ridge, by parallel ridges that rise about 300 ft above the valley floor. The Y-12 Plant and its fenced buffer area are about 0.6 mile wide by 3.2 miles long and cover approximately 4,900 acres. The main industrialized section encompasses approximately 800 acres

A comparative analysis of dynamic grids vs. virtual grids using the A3pviGrid framework.

Science.gov (United States)

Shankaranarayanan, Avinas; Amaldas, Christine

2010-11-01

With the proliferation of Quad/Multi-core micro-processors in mainstream platforms such as desktops and workstations; a large number of unused CPU cycles can be utilized for running virtual machines (VMs) as dynamic nodes in distributed environments. Grid services and its service oriented business broker now termed cloud computing could deploy image based virtualization platforms enabling agent based resource management and dynamic fault management. In this paper we present an efficient way of utilizing heterogeneous virtual machines on idle desktops as an environment for consumption of high performance grid services. Spurious and exponential increases in the size of the datasets are constant concerns in medical and pharmaceutical industries due to the constant discovery and publication of large sequence databases. Traditional algorithms are not modeled at handing large data sizes under sudden and dynamic changes in the execution environment as previously discussed. This research was undertaken to compare our previous results with running the same test dataset with that of a virtual Grid platform using virtual machines (Virtualization). The implemented architecture, A3pviGrid utilizes game theoretic optimization and agent based team formation (Coalition) algorithms to improve upon scalability with respect to team formation. Due to the dynamic nature of distributed systems (as discussed in our previous work) all interactions were made local within a team transparently. This paper is a proof of concept of an experimental mini-Grid test-bed compared to running the platform on local virtual machines on a local test cluster. This was done to give every agent its own execution platform enabling anonymity and better control of the dynamic environmental parameters. We also analyze performance and scalability of Blast in a multiple virtual node setup and present our findings. This paper is an extension of our previous research on improving the BLAST application framework

Desktop grid computing

CERN Document Server

Cerin, Christophe

2012-01-01

Desktop Grid Computing presents common techniques used in numerous models, algorithms, and tools developed during the last decade to implement desktop grid computing. These techniques enable the solution of many important sub-problems for middleware design, including scheduling, data management, security, load balancing, result certification, and fault tolerance. The book's first part covers the initial ideas and basic concepts of desktop grid computing. The second part explores challenging current and future problems. Each chapter presents the sub-problems, discusses theoretical and practical

Oak Ridge Reservation Annual Site environmental report summary for 1994

International Nuclear Information System (INIS)

1995-09-01

This document presents a summary of the information collected for the Oak Ridge Reservation 1994 site environmental report. Topics discussed include: Oak Ridge Reservation mission; ecology; environmental laws; community participation; environmental restoration; waste management; radiation effects; chemical effects; risk to public; environmental monitoring; and radionuclide migration

Mini-grid Policy Tool-kit. Policy and business frameworks for successful mini-grid roll-outs

International Nuclear Information System (INIS)

Franz, Michael; Hayek, Niklas; Peterschmidt, Nico; Rohrer, Michael; Kondev, Bozhil; Adib, Rana; Cader, Catherina; Carter, Andrew; George, Peter; Gichungi, Henry; Hankins, Mark; Kappiah, Mahama; Mangwengwende, Simbarashe E.

2014-01-01

The Mini-grid Policy Tool-kit is for policy makers to navigate the mini-grid policy design process. It contains information on mini-grid operator models, the economics of mini-grids, and necessary policy and regulation that must be considered for successful implementation. The publication specifically focuses on Africa. Progress on extending the electricity grid in many countries has remained slow because of high costs of gird-extension and limited utility/state budgets for electrification. Mini-grids provide an affordable and cost-effective option to extend needed electricity services. Putting in place the right policy for min-grid deployment requires considerable effort but can yield significant improvement in electricity access rates as examples from Kenya, Senegal and Tanzania illustrate. The tool-kit is available in English, French and Portuguese

Smart grid communication-enabled intelligence for the electric power grid

CERN Document Server

Bush, Stephen F

2014-01-01

This book bridges the divide between the fields of power systems engineering and computer communication through the new field of power system information theory. Written by an expert with vast experience in the field, this book explores the smart grid from generation to consumption, both as it is planned today and how it will evolve tomorrow. The book focuses upon what differentiates the smart grid from the ""traditional"" power grid as it has been known for the last century. Furthermore, the author provides the reader with a fundamental understanding of both power systems and communication ne

Challenges facing production grids

Energy Technology Data Exchange (ETDEWEB)

Pordes, Ruth; /Fermilab

2007-06-01

Today's global communities of users expect quality of service from distributed Grid systems equivalent to that their local data centers. This must be coupled to ubiquitous access to the ensemble of processing and storage resources across multiple Grid infrastructures. We are still facing significant challenges in meeting these expectations, especially in the underlying security, a sustainable and successful economic model, and smoothing the boundaries between administrative and technical domains. Using the Open Science Grid as an example, I examine the status and challenges of Grids operating in production today.

Oak Ridge National Laboratory site data for safety-analysis report

International Nuclear Information System (INIS)

Fitzpatrick, F.C.

1982-12-01

The Oak Ridge National Laboratory site data contained herein were compiled in support of the United States Department of Energy (USDOE) Oak Ridge Operations Office Order OR 5481.1. That order sets forth assignment of responsibilities for safety analysis and review responsibilities and provides guidance relative to the content and format of safety analysis reports. The information presented in this document is intended for use by reference in individual safety analysis reports where applicable to support accident analyses or the establishment of design bases of significance to safety, and it is applicable only to Oak Ridge National Laboratory facilities in Bethel and Melton Valleys. This information includes broad descriptions of the site characteristics, radioactive waste handling and monitoring practices, and the organization and operating policies at Oak Ridge National Laboratory. The historical background of the Laboratory is discussed briefly and the overall physical situation of the facilities is described in the following paragraphs

Oak Ridge National Laboratory site data for safety-analysis report

Energy Technology Data Exchange (ETDEWEB)

Fitzpatrick, F.C.

1982-12-01

The Oak Ridge National Laboratory site data contained herein were compiled in support of the United States Department of Energy (USDOE) Oak Ridge Operations Office Order OR 5481.1. That order sets forth assignment of responsibilities for safety analysis and review responsibilities and provides guidance relative to the content and format of safety analysis reports. The information presented in this document is intended for use by reference in individual safety analysis reports where applicable to support accident analyses or the establishment of design bases of significance to safety, and it is applicable only to Oak Ridge National Laboratory facilities in Bethel and Melton Valleys. This information includes broad descriptions of the site characteristics, radioactive waste handling and monitoring practices, and the organization and operating policies at Oak Ridge National Laboratory. The historical background of the Laboratory is discussed briefly and the overall physical situation of the facilities is described in the following paragraphs.

Calendar Year 1997 Annual Groundwater Monitoring Report For The Chestnut Ridge Hydrogeologic Regime At The U.S. Department of Energy Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Jones, S.B.

1998-02-01

This report contains the groundwater monitoring data obtained during calendar year (CY) 1997 in compliance with the Resource Conservation and Recovery Act (RCRA) post-closure permit (PCP) for the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). In July 1997, the Tennessee Department of Environment and Conservation (TDEC) approved modifications to several of the permit conditions that address RCRA pow-closure corrective action groundwater monitoring at the Chestnut Ridge Security Pits (Security Pits), and RCIU4 post-closure detection groundwater monitoring at the Chestnut Ridge Sediment Disposal Basin (Sediment Disposal Basin) and Kerr Hollow Quarry. This report has been prepared in accordance with these modified permit requirements. Also included in this report are the groundwater and surface water monitoring data obtained during CY 1997 for the purposes ofi (1) detection monitoring at nonhazardous solid waste disposal facilities (SWDFS) in accordance with operating permits and applicable regulations, (2) monitoring in accordance with Comprehensive Environmental Response, Compensation, and Recove~ Act Records of Decision (now pefiormed under the Integrated Water Quality Program for the Oak Ridge Reservation), and (3) monitoring needed to comply with U.S. Department of Energy Order 5400.1.

MrGrid: a portable grid based molecular replacement pipeline.

Directory of Open Access Journals (Sweden)

Jason W Schmidberger

Full Text Available BACKGROUND: The crystallographic determination of protein structures can be computationally demanding and for difficult cases can benefit from user-friendly interfaces to high-performance computing resources. Molecular replacement (MR is a popular protein crystallographic technique that exploits the structural similarity between proteins that share some sequence similarity. But the need to trial permutations of search models, space group symmetries and other parameters makes MR time- and labour-intensive. However, MR calculations are embarrassingly parallel and thus ideally suited to distributed computing. In order to address this problem we have developed MrGrid, web-based software that allows multiple MR calculations to be executed across a grid of networked computers, allowing high-throughput MR. METHODOLOGY/PRINCIPAL FINDINGS: MrGrid is a portable web based application written in Java/JSP and Ruby, and taking advantage of Apple Xgrid technology. Designed to interface with a user defined Xgrid resource the package manages the distribution of multiple MR runs to the available nodes on the Xgrid. We evaluated MrGrid using 10 different protein test cases on a network of 13 computers, and achieved an average speed up factor of 5.69. CONCLUSIONS: MrGrid enables the user to retrieve and manage the results of tens to hundreds of MR calculations quickly and via a single web interface, as well as broadening the range of strategies that can be attempted. This high-throughput approach allows parameter sweeps to be performed in parallel, improving the chances of MR success.

A smooth landscape: ending saddle point inflation requires features to be shallow

International Nuclear Information System (INIS)

Battefeld, Diana; Battefeld, Thorsten

2013-01-01

We consider inflation driven near a saddle point in a higher dimensional field space, which is the most likely type of slow roll inflation on the string theoretical landscape; anthropic arguments need to be invoked in order to find a sufficiently flat region. To give all inflatons large masses after inflation and yield a small but positive cosmological constant, the trajectory in field space needs to terminate in a hole on the inflationary plateau, introducing a curved end-of-inflation hypersurface. We compute non-Gaussianities (bi- and tri-spectrum) caused by this curved hyper-surface and find a negative, potentially large, local non-linearity parameter. To be consistent with current observational bounds, the hole needs to be shallow, i.e. considerably wider than deep in natural units. To avoid singling out our vacuum as special (i.e. more special than a positive cosmological constant entails), we deduce that all features on field space should be similarly shallow, severely limiting the type of landscapes one may use for inflationary model building. We justify the use of a truncated Fourier series with random coefficients, which are suppressed the higher the frequency, to model such a smooth landscape by a random potential, as is often done in the literature without a good a priory reason

Sandy berm and beach-ridge formation in relation to extreme sea-levels

DEFF Research Database (Denmark)

Bendixen, Mette; Clemmensen, Lars B; Kroon, Aart

2013-01-01

The formation of berms and their transformation into beach ridges in a micro-tidal environment is coupled to wave run-up and overtopping during extreme sea levels. A straight-forward comparison between extreme sea levels due to storm-surges and active berm levels is impossible in the semi...... prograding spit on the south-eastern Baltic shores of Zealand, Denmark. The modern, sandy beach at this location consists of a beachface with a shallow incipient berm, a mature berm, and a dune-covered beach ridge. It borders a beach-ridge plain to the west, where more than 20 N–S oriented beach ridges...... and swales are present. Measured water-level data from 1991 to 2012 and topographical observations, carried out during fair weather period and during a storm event, provided the basis for a conceptual model exhibiting berm formation and transformation into the local beach-ridge system. The character...

An enhanced structure tensor method for sea ice ridge detection from GF-3 SAR imagery

Science.gov (United States)

Zhu, T.; Li, F.; Zhang, Y.; Zhang, S.; Spreen, G.; Dierking, W.; Heygster, G.

2017-12-01

In SAR imagery, ridges or leads are shown as the curvilinear features. The proposed ridge detection method is facilitated by their curvilinear shapes. The bright curvilinear features are recognized as the ridges while the dark curvilinear features are classified as the leads. In dual-polarization HH or HV channel of C-band SAR imagery, the bright curvilinear feature may be false alarm because the frost flowers of young leads may show as bright pixels associated with changes in the surface salinity under calm surface conditions. Wind roughened leads also trigger the backscatter increasing that can be misclassified as ridges [1]. Thus the width limitation is considered in this proposed structure tensor method [2], since only shape feature based method is not enough for detecting ridges. The ridge detection algorithm is based on the hypothesis that the bright pixels are ridges with curvilinear shapes and the ridge width is less 30 meters. Benefited from GF-3 with high spatial resolution of 3 meters, we provide an enhanced structure tensor method for detecting the significant ridge. The preprocessing procedures including the calibration and incidence angle normalization are also investigated. The bright pixels will have strong response to the bandpass filtering. The ridge training samples are delineated from the SAR imagery in the Log-Gabor filters to construct structure tensor. From the tensor, the dominant orientation of the pixel representing the ridge is determined by the dominant eigenvector. For the post-processing of structure tensor, the elongated kernel is desired to enhance the ridge curvilinear shape. Since ridge presents along a certain direction, the ratio of the dominant eigenvector will be used to measure the intensity of local anisotropy. The convolution filter has been utilized in the constructed structure tensor is used to model spatial contextual information. Ridge detection results from GF-3 show the proposed method performs better compared to the

Online grid impedance estimation for single-phase grid-connected systems using PQ variations

DEFF Research Database (Denmark)

Ciobotaru, Mihai; Teodorescu, Remus; Rodriguez, Pedro

2007-01-01

algorithms are used in order to estimate the value of the grid impedance. The online grid impedance estimation method can be used for compliance with the anti-islanding standard requirements (IEEE1574, IEEE929 and VDE0126) and for adaptive control of the grid-connected converters. The proposed method...

Microbial diversity in subseafloor fluids from Explorer Ridge, Northeast Pacific

Science.gov (United States)

Bolton, S.; Huber, J. A.; Embley, R.; Butterfield, D. A.; Baross, J. A.

2003-12-01

The Gorda, Juan de Fuca and Explorer Ridges are first order spreading centers located in the northeast Pacific. While the Gorda and Juan de Fuca Ridges have been extensively sampled for chemical and microbiological analyses, what little is known about the Explorer Ridge is from preliminary observations made in the mid-1980's. A cruise in 2002 revisited the area and discovered vigorous hydrothermal activity at Magic Mountain, a site located outside the primary rift valley. Explorer Ridge is an important site to compare with other well-described vent sites on the Juan de Fuca Ridge. Our research has focused on describing the phylogenetic and physiological diversity of bacteria and archaea in low temperature hydrothermal fluids in an effort to identify subseafloor indicator organisms and to use the physiological characteristics of these organisms to help constrain subseafloor habitat characteristics. We have previously established that there are microbial taxa that are unique to subseafloor habitats associated with diffuse flow fluids at Axial Seamount and at Endeavour both located on the Juan de Fuca Ridge. These included cultured anaerobic, thermophilic and hyperthermophilic heterotrophs, methanogens and sulfur metabolizers. Moreover, results from molecular phylogeny analyses using the 16S rRNA sequences identified a phylogenetically diverse group of bacteria belonging to the epsilon-proteobacteria. While anaerobic hyperthermophiles were cultured from some diffuse-flow vent sites at Explorer, they were less abundant than at Axial Volcano and Endeavour, and curiously, no methanogens were cultured or detected in 16S rRNA clonal libraries. Like Axial, a diverse group of epsilon-proteobacterial clones were found with many similar to those identified from Axial Seamount and other hydrothermal vent sites, although there appears to be some unique species. The overall bacterial diversity at Explorer appears different than at Axial, possibly linked to temperature or chemical

The Benefits of Grid Networks

Science.gov (United States)

Tennant, Roy

2005-01-01

In the article, the author talks about the benefits of grid networks. In speaking of grid networks the author is referring to both networks of computers and networks of humans connected together in a grid topology. Examples are provided of how grid networks are beneficial today and the ways in which they have been used.

Flood-inundation maps for the Saddle River in Ho-Ho-Kus Borough, the Village of Ridgewood, and Paramus Borough, New Jersey, 2013

Science.gov (United States)

Watson, Kara M.; Niemoczynski, Michal J.

2014-01-01

Digital flood-inundation maps for a 5.4-mile reach of the Saddle River in New Jersey from Hollywood Avenue in Ho-Ho-Kus Borough downstream through the Village of Ridgewood and Paramus Borough to the confluence with Hohokus Brook in the Village of Ridgewood were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Saddle River at Ridgewood, New Jersey (station 01390500). Current conditions for estimating near real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/nwis/uv?site_no=01390500 or at the National Weather Services (NWS) Advanced Hydrologic Prediction Service (AHPS) at http://water.weather.gov/ahps2/hydrograph.php?wfo=okx&gage=rwdn4. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation (March 11, 2011) at the USGS streamgage 01390500, Saddle River at Ridgewood, New Jersey. The hydraulic model was then used to compute 10 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum, North American Vertical Datum of 1988 (NAVD 88), and ranging from 5 ft, the NWS “action and minor flood stage”, to 14 ft, which is the maximum extent of the stage-discharge rating and 0.6 ft higher than the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system 3-meter (9.84-ft) digital elevation model derived from Light Detection and Ranging (lidar) data in order to delineate the area flooded

Data Sharing Report Characterization of Isotope Row Facilities Oak Ridge National Laboratory Oak Ridge TN

Energy Technology Data Exchange (ETDEWEB)

Weaver, Phyllis C. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)

2013-12-12

The U.S. Department of Energy (DOE) Oak Ridge Office of Environmental Management (EM-OR) requested that Oak Ridge Associated Universities (ORAU), working under the Oak Ridge Institute for Science and Education (ORISE) contract, provide technical and independent waste management planning support using funds provided by the American Recovery and Reinvestment Act (ARRA). Specifically, DOE EM-OR requested ORAU to plan and implement a survey approach, focused on characterizing the Isotope Row Facilities located at the Oak Ridge National Laboratory (ORNL) for future determination of an appropriate disposition pathway for building debris and systems, should the buildings be demolished. The characterization effort was designed to identify and quantify radiological and chemical contamination associated with building structures and process systems. The Isotope Row Facilities discussed in this report include Bldgs. 3030, 3031, 3032, 3033, 3033A, 3034, 3036, 3093, and 3118, and are located in the northeast quadrant of the main ORNL campus area, between Hillside and Central Avenues. Construction of the isotope production facilities was initiated in the late 1940s, with the exception of Bldgs. 3033A and 3118, which were enclosed in the early 1960s. The Isotope Row facilities were intended for the purpose of light industrial use for the processing, assemblage, and storage of radionuclides used for a variety of applications (ORNL 1952 and ORAU 2013). The Isotope Row Facilities provided laboratory and support services as part of the Isotopes Production and Distribution Program until 1989 when DOE mandated their shutdown (ORNL 1990). These facilities performed diverse research and developmental experiments in support of isotopes production. As a result of the many years of operations, various projects, and final cessation of operations, production was followed by inclusion into the surveillance and maintenance (S&M) project for eventual decontamination and decommissioning (D&D). The

Geospatializing The Klang Gate Quartz Ridge in Malaysia: A Technological Perspective

Science.gov (United States)

Azahari Razak, Khamarrul; Mohamad, Zakaria; Zaki Ibrahim, Mohd; Azad Rosle, Qalam; Hattanajmie Abd Wahab, Mohd; Abu Bakar, Rabieahtul; Mohd Akib, Wan Abdul Aziz Wan

2015-04-01

Establishment of inventories on geological heritage, or geoheritage resources is a step forward for a comprehensive geoheritage management leading to a better conservation at national and global levels. Compiling and updating inventory of geoheritage is a tedious process and even so in a tropical environment. Malaysia has a tremendous list of geodiversity and generating its national database is a multi-institutional effort and worthwhile investment. However, producing accurate and reliable characteristics of such landform and spectacular geological features remained elusive. The advanced and modern mapping techniques have revolutionized the mapping, monitoring and modelling of the earth surface processes and landforms. Yet the methods for quantification of geodiversity physical features are not fully utilized in Malaysia for a better understanding its processes and activity. This study provides a better insight into the use of advanced active remote sensing technology for characterizing the forested Quartz Ridge in Malaysia. We have developed the novel method and tested in the Klang Gates Quartz Ridge, Selangor. The granitic country rock made up by quartz mineral is known as the longest quartz ridge in Malaysia and characterized by rugged topography, steep slopes, densely vegetated terrain and also rich-biodiversity area. This study presents an integrated field methodological framework and processing scheme by taking into account the climatic, topographic, geologic, and anthropogenic challenges in an equatorial region. Advanced terrestrial laser scanning system was used to accurately capture, map and model the ridge carried out within a relatively stringent time period. The high frequency Global Navigation Satellite System and modern Total Station coupled with the optical satellite and radar imageries and also advanced spatial analysis were fully utilized in the field campaign and data assessment performed during the recent monsoon season. As a result, the mapping

Oak Ridge Reservation, annual site environmental report for 1993

Energy Technology Data Exchange (ETDEWEB)

1994-11-01

The US DOE currently oversees activities on the Oak Ridge Reservation, a government-owned, contractor-operated facility. Three sites compose the reservation; Y-12, Oak Ridge National Laboratory, and K-25. This document contains a summary of environmental monitoring activities on the Oak Ridge Reservation (ORR) and its surroundings. The results summarized in this report are based on the data collected during calendar year (CY) 1993 and compiled in; Environmental Monitoring in the Oak Ridge Reservation: CY 1993 Results. Annual environmental monitoring on the ORR consists of two major activities: effluent monitoring and environmental surveillance. Effluent monitoring is the collection and analysis of samples or measurements of liquid, gaseous, or airborne effluents for the purpose of characterizing and quantifying contaminants and process stream characteristics, assessing radiation and chemical exposures to members of the public, and demonstrating compliance with applicable standards. Environmental surveillance is the collection and analysis of samples of air, water, soil, foodstuffs, biota, and other media from DOE sites and their environs and the measurement of external radiation for purposes of demonstrating compliance with applicable standards, assessing radiation and chemical exposures to members of the public, and assessing effects, if any, on the local environment.

Oak Ridge Reservation, annual site environmental report for 1993

International Nuclear Information System (INIS)

1994-11-01

The US DOE currently oversees activities on the Oak Ridge Reservation, a government-owned, contractor-operated facility. Three sites compose the reservation; Y-12, Oak Ridge National Laboratory, and K-25. This document contains a summary of environmental monitoring activities on the Oak Ridge Reservation (ORR) and its surroundings. The results summarized in this report are based on the data collected during calendar year (CY) 1993 and compiled in; Environmental Monitoring in the Oak Ridge Reservation: CY 1993 Results. Annual environmental monitoring on the ORR consists of two major activities: effluent monitoring and environmental surveillance. Effluent monitoring is the collection and analysis of samples or measurements of liquid, gaseous, or airborne effluents for the purpose of characterizing and quantifying contaminants and process stream characteristics, assessing radiation and chemical exposures to members of the public, and demonstrating compliance with applicable standards. Environmental surveillance is the collection and analysis of samples of air, water, soil, foodstuffs, biota, and other media from DOE sites and their environs and the measurement of external radiation for purposes of demonstrating compliance with applicable standards, assessing radiation and chemical exposures to members of the public, and assessing effects, if any, on the local environment

Power grids

International Nuclear Information System (INIS)

Viterbo, J.

2012-01-01

The implementation of renewable energies represents new challenges for electrical systems. The objective: making power grids smarter so they can handle intermittent production. The advent of smart grids will allow flexible operations like distributing energy in a multidirectional manner instead of just one way and it will make electrical systems capable of integrating actions by different users, consumers and producers in order to maintain efficient, sustainable, economical and secure power supplies. Practically speaking, they associate sensors, instrumentation and controls with information processing and communication systems in order to create massively automated networks. Smart grids require huge investments: for example more than 7 billion dollars have been invested in China and in the Usa in 2010 and France is ranked 9. worldwide with 265 million dollars invested. It is expected that smart grids will promote the development of new business models and a change in the value chain for energy. Decentralized production combined with the probable introduction of more or less flexible rates for sales or purchases and of new supplier-customer relationships will open the way to the creation of new businesses. (A.C.)

Recent trends in grid computing

International Nuclear Information System (INIS)

Miura, Kenichi

2004-01-01

Grid computing is a technology which allows uniform and transparent access to geographically dispersed computational resources, such as computers, databases, experimental and observational equipment etc. via high-speed, high-bandwidth networking. The commonly used analogy is that of electrical power grid, whereby the household electricity is made available from outlets on the wall, and little thought need to be given to where the electricity is generated and how it is transmitted. The usage of grid also includes distributed parallel computing, high through-put computing, data intensive computing (data grid) and collaborative computing. This paper reviews the historical background, software structure, current status and on-going grid projects, including applications of grid technology to nuclear fusion research. (author)

GRID and FMPhI-UNIBA

International Nuclear Information System (INIS)

Babik, M.; Daranyi, T.; Fekete, V.; Stavina, P.; Zagiba, M.; Zenis, T.

2008-01-01

The word GRID has several meanings, so it is not an abbreviation. All of them have in common description of GRID as a form of hardware and software and software solution for distributive computing. Additionally, word GRID is also used for distributive computing of many computers and not one super computer with several processors. It, of course, does not mean that such a supercomputer cannot be a part of the GRID. Typical task for GRID is computer programs execution and to data storage. (Authors)

Proposed plan for the United Nuclear Corporation Disposal Site at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1991-03-01

The US Department of Energy (DOE) in compliance with Section 117(a) of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986, is releasing the proposed plan for remedial action at the United Nuclear Corporation (UNC) Disposal Site located at the DOE Oak Ridge Operations (ORO) Y-12 Plant, Oak Ridge, Tennessee. The purpose of this document is to present and solicit for comment to the public and all interested parties the ''preferred plan'' to remediate the UNC Disposal Site. However, comments on all alternatives are invited

Surface radiological investigations along State Highway 95, Lagoon Road, and Melton Valley Drive, Oak Ridge Reservation, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Tiner, P.F.; Uziel, M.S.; Rice, D.E.; Williams, J.K.

1995-08-01

The surface radiological investigation along State Highway 95, Lagoon Road, and Melton Valley Drive at the Oak Ridge Reservation was conducted as part of the Oak Ridge National Laboratory Environmental Restoration Program Surveillance and Maintenance activities. This report was prepared to document results of the investigation and subsequent remedial actions. The report details surface gamma radiation levels including gamma anomalies; surface beta radiation levels including beta anomalies; results of analysis of soil, water, and vegetation samples and smear samples collected from paved surfaces; remediation activities conducted as a result of the survey; and recommendations for further corrective measures

Probabilistic Learning by Rodent Grid Cells.

Science.gov (United States)

Cheung, Allen

2016-10-01

Mounting evidence shows mammalian brains are probabilistic computers, but the specific cells involved remain elusive. Parallel research suggests that grid cells of the mammalian hippocampal formation are fundamental to spatial cognition but their diverse response properties still defy explanation. No plausible model exists which explains stable grids in darkness for twenty minutes or longer, despite being one of the first results ever published on grid cells. Similarly, no current explanation can tie together grid fragmentation and grid rescaling, which show very different forms of flexibility in grid responses when the environment is varied. Other properties such as attractor dynamics and grid anisotropy seem to be at odds with one another unless additional properties are assumed such as a varying velocity gain. Modelling efforts have largely ignored the breadth of response patterns, while also failing to account for the disastrous effects of sensory noise during spatial learning and recall, especially in darkness. Here, published electrophysiological evidence from a range of experiments are reinterpreted using a novel probabilistic learning model, which shows that grid cell responses are accurately predicted by a probabilistic learning process. Diverse response properties of probabilistic grid cells are statistically indistinguishable from rat grid cells across key manipulations. A simple coherent set of probabilistic computations explains stable grid fields in darkness, partial grid rescaling in resized arenas, low-dimensional attractor grid cell dynamics, and grid fragmentation in hairpin mazes. The same computations also reconcile oscillatory dynamics at the single cell level with attractor dynamics at the cell ensemble level. Additionally, a clear functional role for boundary cells is proposed for spatial learning. These findings provide a parsimonious and unified explanation of grid cell function, and implicate grid cells as an accessible neuronal population

A Theorem on Grid Access Control

Institute of Scientific and Technical Information of China (English)

XU ZhiWei(徐志伟); BU GuanYing(卜冠英)

2003-01-01

The current grid security research is mainly focused on the authentication of grid systems. A problem to be solved by grid systems is to ensure consistent access control. This problem is complicated because the hosts in a grid computing environment usually span multiple autonomous administrative domains. This paper presents a grid access control model, based on asynchronous automata theory and the classic Bell-LaPadula model. This model is useful to formally study the confidentiality and integrity problems in a grid computing environment. A theorem is proved, which gives the necessary and sufficient conditions to a grid to maintain confidentiality.These conditions are the formalized descriptions of local (node) relations or relationship between grid subjects and node subjects.

Transmission grid security

CERN Document Server

Haarla, Liisa; Hirvonen, Ritva; Labeau, Pierre-Etienne

2011-01-01

In response to the growing importance of power system security and reliability, ""Transmission Grid Security"" proposes a systematic and probabilistic approach for transmission grid security analysis. The analysis presented uses probabilistic safety assessment (PSA) and takes into account the power system dynamics after severe faults. In the method shown in this book the power system states (stable, not stable, system breakdown, etc.) are connected with the substation reliability model. In this way it is possible to: estimate the system-wide consequences of grid faults; identify a chain of eve

Pyramid solar micro-grid

Science.gov (United States)

Huang, Bin-Juine; Hsu, Po-Chien; Wang, Yi-Hung; Tang, Tzu-Chiao; Wang, Jia-Wei; Dong, Xin-Hong; Hsu, Hsin-Yi; Li, Kang; Lee, Kung-Yen

2018-03-01

A novel pyramid solar micro-grid is proposed in the present study. All the members within the micro-grid can mutually share excess solar PV power each other through a binary-connection hierarchy. The test results of a 2+2 pyramid solar micro-grid consisting of 4 individual solar PV systems for self-consumption are reported.

Smart Solar Grid. Integration of high penetration of photovoltaic in municipal low voltage distribution grids; Smart Solar Grid. Integration hoher Anteile von Photovoltaik in kommunalen Niederspannungsverteilnetzen

Energy Technology Data Exchange (ETDEWEB)

Ruf, Holger; Heilscher, Gerd [Hochschule Ulm (Germany); Meier, Florian [SWU Netze GmbH, Ulm (Germany)

2012-07-01

The high rate of decentralized generation in low voltage grids especially photovoltaic (PV) put the distribution grid operators to new challenges. Grid operation and grid planning have to respect the volatility and dynamic of decentralized generation now and in the future and adapt their previous proceedings. In the frame of the project Smart Solar Grid was a test site defined in the grid area of the DSO Stadtwerke Ulm/Neu-Ulm GmbH (SWU) to analyze the impact of the PV rise and possible solutions for the grid planning in the future. The first analysis based upon secondly measurements of the first test site. From this were statistical evaluation of the load flows and power variations done. Furthermore were the roof potential analysis results of the test site validated. These data are the base for the development of a forecast system for grid condition parameter. (orig.)

Magdalena Ridge Observatory Interferometer: Status Update

National Research Council Canada - National Science Library

Creech-Eakman, M. J; Bakker, E. J; Buscher, D. F; Coleman, T. A; Haniff, C. A; Jurgenson, C. A; Klinglesmith, III, D. A; Parameswariah, C. B; Romero, V. D; Shtromberg, A. V; Young, J. S

2006-01-01

The Magdalena Ridge Observatory Interferometer (MROI) is a ten element optical and near-infrared imaging interferometer being built in the Magdalena mountains west of Socorro, NM at an altitude of 3230 m...

a comparative study of some robust ridge and liu estimators

African Journals Online (AJOL)

Dr A.B.Ahmed

estimation techniques such as Ridge and Liu Estimators are preferable to Ordinary Least Square. On the other hand, when outliers exist in the data, robust estimators like M, MM, LTS and S. Estimators, are preferred. To handle these two problems jointly, the study combines the Ridge and Liu Estimators with Robust.

Studying the Indian Ocean Ridge System: Agenda for the new century

Digital Repository Service at National Institute of Oceanography (India)

Mukhopadhyay, R.; Iyer, S.D.; Banerjee, R.; Drolia, R.K.

Studies on the Indian Ocean Ridge System, though sporadic, was aimed to map the complete IORS petrologically and tectonically. Three areas are placed for immediate investigation; one in the slow spreading Carlsberg Ridge area, the second, along...

Scaling Up Renewable Energy Generation: Aligning Targets and Incentives with Grid Integration Considerations, Greening The Grid

Energy Technology Data Exchange (ETDEWEB)

Katz, Jessica; Cochran, Jaquelin

2015-05-27

Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of a Greening the Grid toolkit, provides power system planners with tips to help secure and sustain investment in new renewable energy generation by aligning renewable energy policy targets and incentives with grid integration considerations.

Soil sampling and analysis plan for the Bear Creek Valley Floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. In addition to this SAP, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19&D2) presents background information pertaining to this floodplain investigation.

In-Process Analysis Program for the Isolock sampler at the Gunite and Associated Tanks, Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1998-05-01

The In-Process Analysis Program documents the requirements for handling, transporting, and analyzing waste slurry samples gathered by the Bristol Isolock slurry sampler from the Gunite and Associated Tanks at Oak Ridge National Laboratory in Oak Ridge, Tennessee. Composite samples will be gathered during sludge retrieval operations, labeled, transported to the appropriate laboratory, and analyzed for physical and radiological characteristics. Analysis results will be used to support occupational exposure issues, basic process control management issues, and prediction of radionuclide flow

Soil sampling and analysis plan for the Bear Creek Valley Floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1995-03-01

This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. In addition to this SAP, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19 ampersand D2) presents background information pertaining to this floodplain investigation

Impact of Considering 110 kV Grid Structures on the Congestion Management in the German Transmission Grid

Science.gov (United States)

Hoffrichter, André; Barrios, Hans; Massmann, Janek; Venkataramanachar, Bhavasagar; Schnettler, Armin

2018-02-01

The structural changes in the European energy system lead to an increase of renewable energy sources that are primarily connected to the distribution grid. Hence the stationary analysis of the transmission grid and the regionalization of generation capacities are strongly influenced by subordinate grid structures. To quantify the impact on the congestion management in the German transmission grid, a 110 kV grid model is derived using publicly available data delivered by Open Street Map and integrated into an existing model of the European transmission grid. Power flow and redispatch simulations are performed for three different regionalization methods and grid configurations. The results show a significant impact of the 110 kV system and prove an overestimation of power flows in the transmission grid when neglecting subordinate grids. Thus, the redispatch volume in Germany to dissolve bottlenecks in case of N-1 contingencies decreases by 38 % when considering the 110 kV grid.

Contaminated scrap metal management on the Oak Ridge Reservation

International Nuclear Information System (INIS)

Hayden, H.W.; Stephenson, M.J.; Bailey, J.K.; Weir, J.R.; Gilbert, W.C.

1993-01-01

Large quantities of scrap metal are accumulating at the various Department of Energy (DOE) installations across the country as a result of ongoing DOE programs and missions in concert with present day waste management practices. DOE Oak Ridge alone is presently storing around 500,000 tons of scrap metal. The local generation rate, currently estimated at 1,400 tons/yr, is expected to increase sharply over the next couple of years as numerous environmental restoration and decommissioning programs gain momentum. Projections show that 775,000 tons of scrap metal could be generated at the K-25 Site over the next ten years. The Y-12 Plant and Oak Ridge National Laboratory (ORNL) have similar potentials. The history of scrap metal management at Oak Ridge and future challenges and opportunities are discussed

Ridge-like lava tube systems in southeast Tharsis, Mars

Science.gov (United States)

Zhao, Jiannan; Huang, Jun; Kraft, Michael D.; Xiao, Long; Jiang, Yun

2017-10-01

Lava tubes are widely distributed in volcanic fields on a planetary surface and they are important means of lava transportation. We have identified 38 sinuous ridges with a lava-tube origin in southeast Tharsis. The lengths vary between 14 and 740 km, and most of them occur in areas with slopes rate, low lava viscosity, and sustained magma supply during a long period. Besides, lava flow inflation is also important in the formation of the ridge-like lava tubes and some associated features. These lava tubes provide efficient lateral pathways for magma transportation over the relatively low topographic slopes in southeast Tharsis, and they are important for the formation of long lava flows in this region. The findings of this study provide an alternative formation mechanism for sinuous ridges on the martian surface.

76 FR 48927 - RidgeWorth Funds and RidgeWorth Capital Management, Inc.; Notice of Application

Science.gov (United States)

2011-08-09

... the best interests of the Fund and its shareholders, and does not involve a conflict of interest from... enter into and materially amend subadvisory agreements without shareholder approval. Applicants: Ridge... hearing. Interested persons may request a hearing by writing to the Commission's Secretary and serving...

Implementation Plan for Liquid Low-Level Radioactive Waste tank systems at Oak Ridge National Laboratory under the Federal Facility Agreement, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-09-01

This document summarizes the progress that has been made to date in implementing the plans and schedules for meeting the Federal Facility Agreement (FFA) commitments for the Liquid Low-Level Waste (LLLW) System at Oak Ridge National Laboratory (ORNL). These commitments were initially submitted in ES/ER-17 ampersand Dl, Federal Facility Agreement Plans and Schedules for Liquid Low-Level Radioactive Waste Tank Systems at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Information presented in this document provides a comprehensive summary to facilitate understanding of the FFA compliance program for LLLW tank systems and to present plans and schedules associated with remediation, through the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process, of LLLW tank systems that have been removed from service. ORNL has a comprehensive program underway to upgrade the LLLW system as necessary to meet the FFA requirements. The tank systems that are removed from service are being investigated and remediated through the CERCLA process. Waste and risk characterizations have been submitted. Additional data will be prepared and submitted to EPA/TDEC as tanks are taken out of service and as required by the remedial investigation/feasibility study (RI/FS) process. The plans and schedules for implementing the FFA compliance program that were submitted in ES/ER-17 ampersand Dl, Federal Facility Agreement Plans and Schedules for Liquid Low-Level Radioactive Waste tanks Systems at Oak Ridge National Laboratory, Oak Ridge, Tennessee, are updated in this document. Chapter 1 provides general background information and philosophies that lead to the plans and schedules that appear in Chaps. 2 through 5

Stability of Grid-Connected PV Inverters with Large Grid Impedance Variation

DEFF Research Database (Denmark)

Liserre, Marco; Teodorescu, Remus; Blaabjerg, Frede

2004-01-01

Photovoltaic (PV) inverters used in dispersed power generation of houses in the range of 1-5 kW are currently available from several manufactures. However, large grid impedance variation is challenging the control and the grid filter design in terms of stability. In fact the PV systems are well...... suited for loads connected in a great distance to the transformer (long wires) and the situation becomes even more difficult in low-developed remote areas characterized by low power transformers and long distribution wires with high grid impedance. Hence a theoretical analysis is needed because the grid...... impedance variation leads to dynamic and stability problems both in the low frequency range (around the current controller bandwidth frequency) as well as in the high frequency range (around the LCL-filter resonance frequency). In the low frequency range the possible variation of the impedance challenges...

TIGER: Turbomachinery interactive grid generation

Science.gov (United States)

Soni, Bharat K.; Shih, Ming-Hsin; Janus, J. Mark

1992-01-01

A three dimensional, interactive grid generation code, TIGER, is being developed for analysis of flows around ducted or unducted propellers. TIGER is a customized grid generator that combines new technology with methods from general grid generation codes. The code generates multiple block, structured grids around multiple blade rows with a hub and shroud for either C grid or H grid topologies. The code is intended for use with a Euler/Navier-Stokes solver also being developed, but is general enough for use with other flow solvers. TIGER features a silicon graphics interactive graphics environment that displays a pop-up window, graphics window, and text window. The geometry is read as a discrete set of points with options for several industrial standard formats and NASA standard formats. Various splines are available for defining the surface geometries. Grid generation is done either interactively or through a batch mode operation using history files from a previously generated grid. The batch mode operation can be done either with a graphical display of the interactive session or with no graphics so that the code can be run on another computer system. Run time can be significantly reduced by running on a Cray-YMP.

New grid-planning and certification approaches for the large-scale offshore-wind farm grid-connection systems

Energy Technology Data Exchange (ETDEWEB)

Heising, C.; Bartelt, R. [Avasition GmbH, Dortmund (Germany); Zadeh, M. Koochack; Lebioda, T.J.; Jung, J. [TenneT Offshore GmbH, Bayreuth (Germany)

2012-07-01

Stable operation of the offshore-wind farms (OWF) and stable grid connection under stationary and dynamic conditions are essential to achieve a stable public power supply. To reach this aim, adequate grid-planning and certification approaches are a major advantage. Within this paper, the fundamental characteristics of the offshore-wind farms and their grid-connection systems are given. The main goal of this research project is to study the stability of the offshore grid especially in terms of subharmonic stability for the likely future extension stage of the offshore grids i.e. having parallel connection of two or more HVDC links and for certain operating scenarios e.g. overload scenario. The current requirements according to the grid code are not the focus of this research project. The goal is to study and define potential additional grid code requirements, simulations, tests and grid planning methods for the future. (orig.)

Chemical and Mineralogical Characterization of a Hematite-bearing Ridge on Mauna Kea, Hawaii: A Potential Mineralogical Process Analog for the Mount Sharp Hematite Ridge

Science.gov (United States)

Graff, T. G.; Morris, R. V.; Ming, D. W.; Hamilton, J. C.; Adams, M.; Fraeman, A. A.; Arvidson, R. E.; Catalano, J. G.; Mertzman, S. A.

2014-01-01

The Mars Science Laboratory (MSL) rover Curiosity landed in Gale Crater in August 2012 and is currently roving towards the layered central mound known as Mount Sharp [1]. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) hyperspectral data indicate Mount Sharp contains an 5 km stratigraphic sequence including Fe-Mg smectites, hematite, and hydrated sulfates in the lower layers separated by an unconformity from the overlying anhydrous strata [1,2,3]. Hematite was initially detected in CRISM data to occur in the lower sulfate layers on the north side of the mound [2]. [3] further mapped a distinct hematite detection occurring as part of a 200 m wide ridge that extends 6.5 km NE-SW, approximately parallel with the base of Mount Sharp. It is likely a target for in-situ analyses by Curiosity. We document here the occurrence of a stratum of hematite-bearing breccia that is exposed on the Puu Poliahu cinder cone near the summit of Mauna Kea volcano (Hawaii) (Fig.1). The stratum is more resistant to weathering than surrounding material, giving it the appearance of a ridge. The Mauna Kea hematite ridge is thus arguably a potential terrestrial mineralogical and process analog for the Gale Crater hematite ridge. We are acquiring a variety of chemical and mineralogical data on the Mauna Kea samples, with a focus on the chemical and mineralogical information already available or planned for the Gale hematite ridge.

Online Grid Measurement and ENS Detection for PV Inverter Running on Highly Inductive Grid

DEFF Research Database (Denmark)

Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

2004-01-01

Photovoltaic (PV) and other sources of renewable energy are being used increasingly in grid-connected systems, for which stronger power quality requirements are being issued. Continuous grid monitoring should be considered so as to provide safe connections and disconnections from the grid...

NetJobs: A new approach to network monitoring for the Grid using Grid jobs

OpenAIRE

Pagano, Alfredo

2011-01-01

With grid computing, the far-fl�ung and disparate IT resources act as a single "virtual datacenter". Grid computing interfaces heterogeneous IT resources so they are available when and where we need them. Grid allows us to provision applications and allocate capacity among research and business groups that are geographically and organizationally dispersed. Building a high availability Grid is hold as the next goal to achieve: protecting against computer failures and site failures to avoid dow...

Improved voltage performance of the Oak Ridge 25URC tandem accelerator

International Nuclear Information System (INIS)

Meigs, M.J.; Jones, C.M.; Haynes, D.L.; Juras, R.C.; Ziegler, N.F.; Roatz, J.E.; Rathmell, R.D.

1989-01-01

This paper reports on the Oak Ridge 25URC tandem electrostatic accelerator one of two accelerators operated by the Holifield Heavy Ion Research Facility (HHIRF) at the Oak Ridge National Laboratory. Placed into routine service in 1982, the accelerator has provided a wide range of heavy ion beams for research in nuclear and atomic physics. These beams have been provided both directly and after further acceleration by the Oak Ridge Isochronous Cyclotron (ORIC). Show schematically in this paper, the tandem accelerator is a model 25URC Pelletron accelerator

Calendar year 1993 groundwater quality report for the Chestnut Ridge Hydrogeologic Regime Y-12 Plant, Oak Ridge, Tennessee. 1993 Groundwater quality data interpretations and proposed program modifications

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-09-01

This groundwater quality report (GWQR) contains an evaluation of the groundwater quality data obtained during the 1993 calendar year (CY) at several hazardous and non-hazardous waste management facilities associated with the US DOE Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. The groundwater quality data are presented in Part 1 of the GWQR submitted by Martin Marietta Energy Systems, Inc. to the Tennessee Department of Environment and Conservation (TDEC) in February 1994. Groundwater quality data evaluated in this report were obtained at several hazardous and non-hazardous waste management sites located within the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). The Chestnut Ridge Regime encompasses a section of Chestnut Ridge south of the Y-12 Plant and is one of three hydrogeologic regimes defined for the purposes of groundwater quality monitoring at the plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The annual GWQR for the Chestnut Ridge Regime is completed in two parts. Part 1 consists primarily of data appendices and serves as a reference for the groundwater quality data obtained each CY under the lead of the Y-12 Plant GWPP. Because it contains information needed to comply with Resource Conservation and Recovery Act (RCRA) interim status assessment monitoring and reporting requirements, the Part 1 GWQR is submitted to the TDEC by the RCRA reporting deadline (March 1 of the following CY). Part 2 (this report) contains an evaluation of the data with respect to regime-wide groundwater quality, presents the findings and status of ongoing hydrogeologic studies, describes changes in monitoring priorities, and presents planned modifications to the groundwater sampling and analysis activities.

Calendar year 1993 groundwater quality report for the Chestnut Ridge Hydrogeologic Regime Y-12 Plant, Oak Ridge, Tennessee. 1993 Groundwater quality data interpretations and proposed program modifications

International Nuclear Information System (INIS)

1994-09-01

This groundwater quality report (GWQR) contains an evaluation of the groundwater quality data obtained during the 1993 calendar year (CY) at several hazardous and non-hazardous waste management facilities associated with the US DOE Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. The groundwater quality data are presented in Part 1 of the GWQR submitted by Martin Marietta Energy Systems, Inc. to the Tennessee Department of Environment and Conservation (TDEC) in February 1994. Groundwater quality data evaluated in this report were obtained at several hazardous and non-hazardous waste management sites located within the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). The Chestnut Ridge Regime encompasses a section of Chestnut Ridge south of the Y-12 Plant and is one of three hydrogeologic regimes defined for the purposes of groundwater quality monitoring at the plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The annual GWQR for the Chestnut Ridge Regime is completed in two parts. Part 1 consists primarily of data appendices and serves as a reference for the groundwater quality data obtained each CY under the lead of the Y-12 Plant GWPP. Because it contains information needed to comply with Resource Conservation and Recovery Act (RCRA) interim status assessment monitoring and reporting requirements, the Part 1 GWQR is submitted to the TDEC by the RCRA reporting deadline (March 1 of the following CY). Part 2 (this report) contains an evaluation of the data with respect to regime-wide groundwater quality, presents the findings and status of ongoing hydrogeologic studies, describes changes in monitoring priorities, and presents planned modifications to the groundwater sampling and analysis activities

Summary review of the chemical characterization of liquid and sludge contained in the Old Hydrofracture tanks, Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Francis, C.W.; Herbes, S.E.

1997-02-01

This report presents analytical data developed from samples collected from the five inactive tanks located at the Old Hydrofracture Facility (OHF) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The samples were collected during December 1995 and January 1996. The purpose of the sampling and analysis project was (1) to determine whether the tank contents meet ORNL waste acceptance criteria, as specified in the Oak Ridge National Laboratory, Liquid Waste Treatment Systems, Waste Evaluation Criteria; (2) to determine various physical properties of the tank contents that would affect the design of a sludge mobilization system; and (3) to gather information to support a baseline risk assessment. The report focuses on the analytical results used to evaluate the tank contents with regard to nuclear criticality safety requirements and to regulatory waste characterization

Wireless Communications in Smart Grid

Science.gov (United States)

Bojkovic, Zoran; Bakmaz, Bojan

Communication networks play a crucial role in smart grid, as the intelligence of this complex system is built based on information exchange across the power grid. Wireless communications and networking are among the most economical ways to build the essential part of the scalable communication infrastructure for smart grid. In particular, wireless networks will be deployed widely in the smart grid for automatic meter reading, remote system and customer site monitoring, as well as equipment fault diagnosing. With an increasing interest from both the academic and industrial communities, this chapter systematically investigates recent advances in wireless communication technology for the smart grid.

Observation of pressure ridges in SAR images of sea ice: Scattering theory and comparison with observations

Science.gov (United States)

Vesecky, J. F.; Daida, J. M.; Shuchman, R. A.; Onstott, R. H.; Camiso, J. C.

1993-01-01

Ridges and keels (hummocks and bummocks) in sea ice flows are important in sea ice research for both scientific and practical reasons. Sea ice movement and deformation is driven by internal and external stresses on the ice. Ridges and keels play important roles in both cases because they determine the external wind and current stresses via drag coefficients. For example, the drag coefficient over sea ice can vary by a factor of several depending on the fluid mechanical roughness length of the surface. This roughness length is thought to be strongly dependent on the ridge structures present. Thus, variations in ridge and keel structure can cause gradients in external stresses which must be balanced by internal stresses and possibly fracture of the ice. Ridging in sea ice is also a sign of fracture. In a practical sense, large ridges form the biggest impediment to surface travel over the ice or penetration through sea ice by ice-strengthened ships. Ridges also play an important role in the damage caused by sea ice to off-shore structures. Hence, observation and measurement of sea ice ridges is an important component of sea ice remote sensing. The research reported here builds on previous work, estimating the characteristics of ridges and leads in sea ice from SAR images. Our objective is to develop methods for quantitative measurement of sea ice ridges from SAR images. To make further progress, in particular, to estimate ridge height, a scattering model for ridges is needed. Our research approach for a ridge scattering model begins with a survey of the geometrical properties of ridges and a comparison with the characteristics of the surrounding ice. For this purpose we have used airborne optical laser (AOL) data collected during the 1987 Greenland Sea Experiment. These data were used to generate a spatial wavenumber spectrum for height variance for a typical ridge - the typical ridge is the average over 10 large ridges. Our first-order model radar scattering includes

Fuel Cell Backup Power System for Grid Service and Micro-Grid in Telecommunication Applications: Preprint

Energy Technology Data Exchange (ETDEWEB)

Ma, Zhiwen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eichman, Joshua D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurtz, Jennifer M [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-03-22

This paper presents the feasibility and economics of using fuel cell backup power systems in telecommunication cell towers to provide grid services (e.g., ancillary services, demand response). The fuel cells are able to provide power for the cell tower during emergency conditions. This study evaluates the strategic integration of clean, efficient, and reliable fuel cell systems with the grid for improved economic benefits. The backup systems have potential as enhanced capability through information exchanges with the power grid to add value as grid services that depend on location and time. The economic analysis has been focused on the potential revenue for distributed telecommunications fuel cell backup units to provide value-added power supply. This paper shows case studies on current fuel cell backup power locations and regional grid service programs. The grid service benefits and system configurations for different operation modes provide opportunities for expanding backup fuel cell applications responsive to grid needs.

Wetland Survey of Selected Areas in the Oak Ridge Y-12 Plant Area of Responsibilty, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Rosensteel.

1997-01-01

This document was prepared to summarize wetland surveys performed in the Y- 1 2 Plant area of responsibility in June and July 1994. Wetland surveys were conducted in three areas within the Oak Ridge Y- 12 Plant area of responsibility in June and July 1994: the Upper East Fork Poplar Creek (UEFPC) Operable Unit (OU), part of the Bear Creek Valley OU (the upper watershed of Bear Creek from the culvert under Bear Creek Road upstream through the Y-12 West End Environmental Management Area, and the catchment of Bear Creek North Tributary 1), and part of Chestnut Ridge OU 2 (the McCoy Branch area south of Bethel Valley Road). Using the criteria and methods set forth in the Wetlands Delineation Manual, 18 wetland areas were identified in the 3 areas surveyed; these areas were classified according to the system developed by Cowardin. Fourteen wetlands and one wetland/pond area that are associated with disturbed or remnant stream channels and seeps were identified in the UEFPC OU. Three wetlands were identified in the Bear Creek Valley OU portion of the survey area. One wetland was identified in the riparian zone of McCoy Branch in the southern portion of Chestnut Ridge OU 2

The DataGrid Project

CERN Document Server

Ruggieri, F

2001-01-01

An overview of the objectives and status of the DataGrid Project is presented, together with a brief introduction to the Grid metaphor and some references to the Grid activities and initiatives related to DataGrid. High energy physics experiments have always requested state of the art computing facilities to efficiently perform several computing activities related with the handling of large amounts of data and fairly large computing resources. Some of the ideas born inside the community to enhance the user friendliness of all the steps in the computing chain have been, sometimes, successfully applied also in other contexts: one bright example is the World Wide Web. The LHC computing challenge has triggered inside the high energy physics community, the start of the DataGrid Project. The objective of the project is to enable next generation scientific exploration requiring intensive computation and analysis of shared large-scale databases. (12 refs).

gCube Grid services

CERN Document Server

Andrade, Pedro

2008-01-01

gCube is a service-based framework for eScience applications requiring collaboratory, on-demand, and intensive information processing. It provides to these communities Virtual Research Environments (VREs) to support their activities. gCube is build on top of standard technologies for computational Grids, namely the gLite middleware. The software was produced by the DILIGENT project and will continue to be supported and further developed by the D4Science project. gCube reflects within its name a three-sided interpretation of the Grid vision of resource sharing: sharing of computational resources, sharing of structured data, and sharing of application services. As such, gCube embodies the defining characteristics of computational Grids, data Grids, and virtual data Grids. Precisely, it builds on gLite middleware for managing distributed computations and unstructured data, includes dedicated services for managing data and metadata, provides services for distributed information retrieval, allows the orchestration...

Effects of ridge and furrow rainfall harvesting system on Elymus ...

African Journals Online (AJOL)

ARL

2012-05-10

May 10, 2012 ... A ridge-furrow rainfall harvesting system (RFRHS) was designed to increase the available soil water for .... The solar energy passed through the plastic-film and heated up the air and the surface soil of ridge and then the heat was trapped by the greenhouse effect (Zhou et al., 2009). Meanwhile, the.

Research on wind power grid-connected operation and dispatching strategies of Liaoning power grid

Science.gov (United States)

Han, Qiu; Qu, Zhi; Zhou, Zhi; He, Xiaoyang; Li, Tie; Jin, Xiaoming; Li, Jinze; Ling, Zhaowei

2018-02-01

As a kind of clean energy, wind power has gained rapid development in recent years. Liaoning Province has abundant wind resources and the total installed capacity of wind power is in the forefront. With the large-scale wind power grid-connected operation, the contradiction between wind power utilization and peak load regulation of power grid has been more prominent. To this point, starting with the power structure and power grid installation situation of Liaoning power grid, the distribution and the space-time output characteristics of wind farm, the prediction accuracy, the curtailment and the off-grid situation of wind power are analyzed. Based on the deep analysis of the seasonal characteristics of power network load, the composition and distribution of main load are presented. Aiming at the problem between the acceptance of wind power and power grid adjustment, the scheduling strategies are given, including unit maintenance scheduling, spinning reserve, energy storage equipment settings by the analysis of the operation characteristics and the response time of thermal power units and hydroelectric units, which can meet the demand of wind power acceptance and provide a solution to improve the level of power grid dispatching.

Grid cut-off-effect

International Nuclear Information System (INIS)

Fischer, U.; Vosshenrich, R.; Grabbe, E.

1992-01-01

Tilting of a grid during portable radiography leads to uneven exposures, and errors greater than 3 0 can lead to errors in interpretation. Differentiation from abnormal findings can be made by recognising exposure difference of extrathoracic comparable areas. The difficulties caused by tilting of the grid can be reduced by increasing the film focus distance and by using suitable grids. A new cassette holder with an integrated balance makes it possible to correct tilting of the grid rapidly and effectively. This results in improved image quality which can be applied not only to conventional exposure systems but is also of advantage when using digital methods. (orig.) [de

Retrospective success and survival rates of dental implants placed after a ridge preservation procedure.

Science.gov (United States)

Apostolopoulos, Peter; Darby, Ivan

2017-04-01

Ridge preservation is any procedure that takes place at the time of, or shortly after an extraction, to minimise resorption of the ridge and maximise bone formation within the socket. The aim of this project is to investigate the outcome of implant treatment following ridge preservation and compare it to an ungrafted implant control group. Following ethics approval, an electronic and manual search of patient records was conducted, and appropriate cases of implant placement following a ridge preservation procedure were identified. Forty-two patients with 51 implants at ridge-preserved sites were examined by one author (PA) with the following parameters assessed at each implant: pocket probing depth, bleeding on probing, presence/absence of plaque and radiographic bone loss. Clinical and radiographic findings were compared to an ungrafted implant control group and analysed by years in function. There was a 100% survival rate of implants in ridge-preserved sites. In the majority of cases, ridge preservation was performed in the anterior maxilla with a flap raised and the use of deproteinised bovine bone mineral and collagen membrane materials. The mean time in function was 31 (±24) months with a range of 2-102 months. Differences in the mean PPD, BOP, plaque index and radiographic bone loss were not statistically significant between implants at ridge-preserved or ungrafted sites. The overall success rate was around 58% for ungrafted implants and around 51% for implants in ridge-preserved sites. However, this difference was not statistically significant. In this retrospective study, implant placement at ridge-preserved sites was a predictable procedure that led to very high survival rates and similar success rates to implant placement at ungrafted sites. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Modeling and Experiments on Ballistic Impact into UHMWPE Yarns Using Flat and Saddle-Nosed Projectiles

Directory of Open Access Journals (Sweden)

Stuart Leigh Phoenix

2017-03-01

Full Text Available Yarn shooting experiments were conducted to determine the ballistically-relevant, Young’s modulus and tensile strength of ultra-high molecular weight polyethylene (UHMWPE fiber. Target specimens were Dyneema® SK76 yarns (1760 dtex, twisted to 40 turns/m, and initially tensioned to stresses ranging from 29 to 2200 MPa. Yarns were impacted, transversely, by two types of cylindrical steel projectiles at velocities ranging from 150 to 555 m/s: (i a reverse-fired, fragment simulating projectile (FSP where the flat rear face impacted the yarn rather than the beveled nose; and (ii a ‘saddle-nosed projectile’ having a specially contoured nose imparting circular curvature in the region of impact, but opposite curvature transversely to prevent yarn slippage off the nose. Experimental data consisted of sequential photographic images of the progress of the triangular transverse wave, as well as tensile wave speed measured using spaced, piezo-electric sensors. Yarn Young’s modulus, calculated from the tensile wave-speed, varied from 133 GPa at minimal initial tension to 208 GPa at the highest initial tensions. However, varying projectile impact velocity, and thus, the strain jump on impact, had negligible effect on the modulus. Contrary to predictions from the classical Cole-Smith model for 1D yarn impact, the critical velocity for yarn failure differed significantly for the two projectile types, being 18% lower for the flat-faced, reversed FSP projectile compared to the saddle-nosed projectile, which converts to an apparent 25% difference in yarn strength. To explain this difference, a wave-propagation model was developed that incorporates tension wave collision under blunt impact by a flat-faced projectile, in contrast to outward wave propagation in the classical model. Agreement between experiment and model predictions was outstanding across a wide range of initial yarn tensions. However, plots of calculated failure stress versus yarn pre

Curvilinear ridges and related features in southwest Cydonia Mensae, Mars

Science.gov (United States)

Parker, Timothy J.; Schneeberger, Dale M.; Pieri, David C.; Saunders, R. Stephen

1987-01-01

Examined is a region on Mars in southwest Cydonia Mensae (32 deg lat., 17 deg long.) just northwest of the lowland/upland boundary escarpment. The dominant morphological features in this region are the clusters of large massifs and plateau outliers (PI), knobby material (K), and smooth lowland plains (Ps). Surrounding the clusters and linking many isolated knobs is a system of curvilinear ridges and arcuate terrain boundaries which tend to separate the massifs and knobs from the smooth plains. Curvilinear ridges are arcuate to nearly linear and smoother in plan than wrinkle ridges and show no apparent correlation with regional structural grain. They are typically 5 to 10 km long but can range from as little as 2 or 3 km to greater than 50 km long. The widths vary from about 100 m to as much as 2 km. Curvilinear ridges are most numerous within 100 km of the lowland/upland boundary escarpment and are associated with massifs and knobby terrain. Arcuate terrain boundaries appear between units of different apparent albedo or arcuate breaks in slope.

Ridge Width Correlations between Inked Prints and Powdered Latent Fingerprints.

Science.gov (United States)

De Alcaraz-Fossoul, Josep; Barrot-Feixat, Carme; Zapico, Sara C; Mancenido, Michelle; Broatch, Jennifer; Roberts, Katherine A; Carreras-Marin, Clara; Tasker, Jack

2017-10-03

A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges' widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO 2 . The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints , and these should be used as the comparison standard for future aging studies. © 2017 American Academy of Forensic Sciences.

Department of Energy Environmental Management Plan for Oak Ridge Reservation

International Nuclear Information System (INIS)