WorldWideScience

Sample records for ball grid array

  1. Silicon ball grid array chip carrier

    Science.gov (United States)

    Palmer, David W.; Gassman, Richard A.; Chu, Dahwey

    2000-01-01

    A ball-grid-array integrated circuit (IC) chip carrier formed from a silicon substrate is disclosed. The silicon ball-grid-array chip carrier is of particular use with ICs having peripheral bond pads which can be reconfigured to a ball-grid-array. The use of a semiconductor substrate such as silicon for forming the ball-grid-array chip carrier allows the chip carrier to be fabricated on an IC process line with, at least in part, standard IC processes. Additionally, the silicon chip carrier can include components such as transistors, resistors, capacitors, inductors and sensors to form a "smart" chip carrier which can provide added functionality and testability to one or more ICs mounted on the chip carrier. Types of functionality that can be provided on the "smart" chip carrier include boundary-scan cells, built-in test structures, signal conditioning circuitry, power conditioning circuitry, and a reconfiguration capability. The "smart" chip carrier can also be used to form specialized or application-specific ICs (ASICs) from conventional ICs. Types of sensors that can be included on the silicon ball-grid-array chip carrier include temperature sensors, pressure sensors, stress sensors, inertia or acceleration sensors, and/or chemical sensors. These sensors can be fabricated by IC processes and can include microelectromechanical (MEM) devices.

  2. A Machine Vision System for Ball Grid Array Package Inspection

    Institute of Scientific and Technical Information of China (English)

    XIA Nian-jiong; CAO Qi-xin; LEE Jey

    2005-01-01

    An optical inspection method of the Ball Grid Array package (BGA) was proposed by using a machine vision system. The developed machine vision system could get main critical factors for BGA quality evaluation, such as the height of solder ball, diameter, pitch and coplanarity. The experiment has proved that this system is available for BGA failure detection.

  3. Ball-grid array architecture for microfabricated ion traps

    Energy Technology Data Exchange (ETDEWEB)

    Guise, Nicholas D., E-mail: nicholas.guise@gtri.gatech.edu; Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M. [Georgia Tech Research Institute, Atlanta, Georgia 30332 (United States); Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W. [Honeywell International, Golden Valley, Minnesota 55422 (United States)

    2015-05-07

    State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with {sup 40}Ca{sup +} ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with {sup 171}Yb{sup +} ions in a second BGA trap.

  4. Life Prediction of Ball Grid Array Soldered Joints under Thermal Cycling Loading by Fracture Mechanics Method

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fatigue crack propagation life of ball grid array (BGA) soldered joints during thermal cycling loading was investigated by fracture mechanics approach using finite element analysis. The relationships between the strain energy release rate (G) and crack size (α), thermal cycle numbers (N) can be derived. Based on the relationships, fatigue life of the soldered joints was determined. The results showed that crack propagation life was higher than crack initiation life. Therefore, it appears that it is more appropriate to predict the fatigue life of soldered joints using the fracture mechanics method.

  5. Study on solder joint reliability of ceramic ball grid array component based on design of experiment method

    Institute of Scientific and Technical Information of China (English)

    Wu Zhaohua; Huang Chunyue; Zhou Dejian

    2006-01-01

    Four process parameters, pad diameter, stencil thickness, ball diameter and stand-off were chosen as four control factors.By using an L25 ( 56 ) orthogonal array the ceramic ball grid array ( CBGA ) solder joints which have 25 different combinations of process parameters were designed.The numerical models of all the 25 CBGA solder joints were developed using the Surface Evolver.Utilizing the surface coordinate exported from the 25 CBGA solder joints numerical models, the finite element analysis models were set up and the nonlinear finite element analysis of the CBGA solder joints under thermal cycles were performed by ANSYS.The thermal fatigne life of CBGA solder joint was calculated using Coffin-Manson equation.Based on the calculated thermal fatigue life results, the range analysis and the variance analysis were performed.The results show that the fatigue life of CBGA solder joint is affected by the pad diameter, the stencil thickness, the ball diameter and the standoff in a descending order, the best combination of process parameters results in the longest fatigue life is 0.07 mm stand-off,0.125 mm stencil thickness of, 0.85 mm ball diameter and 0.89 mm pad diameter.With 95% confidence the pad diameter has a significant effect on the reliability of CBGA solder joints whereas the stand-off, the stencil thickness and the ball diameter have little effect on the reliability of CBGA solder joints.

  6. The Investigation of Die Back Edge Cracking in Flip Chip Ceramic Ball Grid Array Package (FC-CBGA

    Directory of Open Access Journals (Sweden)

    Zainudin Kornain

    2011-09-01

    Full Text Available The cracking between die back edge and top fillet for Flip Chip Ceramic Ball Grid Array (FC-CBGA package due to thermal cycling have been investigated in this study. Finite Element Analysis (FEA model was used to analyze the effect of fillet geometry and material properties of underfill upon stresses along the die back edge. The thermo-mechanical properties of commercial underfill were obtained by using Thermal Mechanical Analyzer (TMA and Dynamic Mechanical Analyzer (DMA as the input for the simulation. Die stress distribution for different fillet height and width were generated to depict variation of stress due thermal loading and the variations of tensile stress were discussed for parameter optimization. The effect of different underfill material properties were discussed as well for thermal stress reliability improvement.

  7. Micro-Ball Lens Array Fabrication in Photoresist Using Ptfe Hydrophobic Effect

    CERN Document Server

    Shyu Ruey Fang; Tsai Wen Ren; Tsai Jhy Cherng

    2007-01-01

    This paper presents a simple method to fabricate micro-ball lens and its array. The key technology is to use the hydrophobic characteristics of polyterafluoroethylene (PTFE) substrate. High contact angle between melted photoresist pattern and PTFE can generate micro-ball lens and its array. PTFE thin film was spun onto a silicon wafer and dried in oven. Photoresist AZ4620 was used to pattern micro-columns with different diameters 60, 70 and 80 $\\mu$m. A thermal reflow process then was applied to melt these micro-column patterns resulted in micro-ball lens array. The achieved micro-ball lens array with diameter 98 $\\mu$m was fabricated using 80 $\\mu$m in diameter patterns. This method provides a simple fabrication process and low material cost.

  8. Shaping of steel mold surface of lens array by electrical discharge machining with spherical ball electrode.

    Science.gov (United States)

    Takino, Hideo; Hosaka, Takahiro

    2016-06-20

    We propose a method for fabricating a spherical lens array mold by electrical discharge machining (EDM) with a ball-type electrode. The electrode is constructed by arranging conductive spherical balls in an array. To fundamentally examine the applicability of the proposed EDM method to the fabrication of lens array molds, we use an electrode having a single ball to shape a lens array mold made of stainless steel with 16 spherical elements, each having a maximum depth of 0.5 mm. As a result, a mold surface is successfully shaped with a peak-to-valley shape accuracy of approximately 10 μm, and an average surface roughness of 0.85 μm.

  9. Shaping of steel mold surface of lens array by electrical discharge machining with spherical ball electrode.

    Science.gov (United States)

    Takino, Hideo; Hosaka, Takahiro

    2016-06-20

    We propose a method for fabricating a spherical lens array mold by electrical discharge machining (EDM) with a ball-type electrode. The electrode is constructed by arranging conductive spherical balls in an array. To fundamentally examine the applicability of the proposed EDM method to the fabrication of lens array molds, we use an electrode having a single ball to shape a lens array mold made of stainless steel with 16 spherical elements, each having a maximum depth of 0.5 mm. As a result, a mold surface is successfully shaped with a peak-to-valley shape accuracy of approximately 10 μm, and an average surface roughness of 0.85 μm. PMID:27409126

  10. Resistor array infrared nonuniformity correction based on sparse grid

    Science.gov (United States)

    He, Xudong; Qiu, Jiang; Zhang, Qiao; Du, Huijie; Zhao, Hongming

    2013-10-01

    Resistor array plays a vital role in emulation of the IR control and guide system. However, its serious nonuniformity confines the range of its application. Therefore, in order to obtain an available IR image, nonuniformity correction (NUC) is necessary. The traditional method is sparse grid and flood which only take the array's nonuniformity into account. In this paper we present an improved sparse grid method which considers the whole system which affects the array's nonuniformity by dividing the NUC process into different gray levels. In each gray level, we can take two points or several points to calculate the nonuniformity of every block which is divided before correction. After that, we can have several characteristic curves which will be operated with curve fitting. By this means, we will correct the nonuniformity. At last, through the experiment of a number of images, we find the residual nonuniformity associated with random noise is about 0.2% after the correction.

  11. Innovative Columnar Type of Grid Array SJ BIST HALT Method Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Ridgetop will develop a superior method for testing and qualifying columnar type of grid arrays such as field programmable gate arrays (FPGAs) packaged in column...

  12. GMAP—Grid aware Monte—Carlo Array Processor

    Institute of Scientific and Technical Information of China (English)

    A.Moreton; G.D.Patel; 等

    2001-01-01

    The Monte-Carlo Array Processor(MAP) has been designed using commodity off the shelf (COTS) items to provide the CPU requirements of full event simulation for the LHC experiments.The solution is however completely general,so and CPU intensive application with limited input requirements can be run on the system.Operating control software has been written to manage the data flow oiver the 100 BaseT ethernet connecting the 300 nodes(400 MHz PII's) to the 6 master control nodes 700 MHz PIII's each with 500Gb of disk),Upgrade to 1000 nodes is plkanned.Job control software that allows the user to run the same job on all nodes,whilst allowing for small differences in initialisation parameters between nodes has also been written.GMAP is the GRID aware MAP control software,This allows remote job preparation and submission using globus toolkit for authentification and communication.The software will be available and opens the possibility for doing massive Monte Carlo production over several remote MAP sites simultaneously.

  13. Grid connected hybrid dispersed power generators based on PV array and wind-driven induction generator

    International Nuclear Information System (INIS)

    A grid connected hybrid scheme for residential power supply based on an integrated photo-voltaic (PV) array and a wind-driven induction generator (IG) has been proposed in this paper. This new grid-connected configuration employs a closed loop controller at the inverter interfaced to the PV array to regulate the current fed to the grid. By varying the reference current to the controller the PV array meets the reactive power needs of the induction generator and also acts as a source of real power to the grid. A dynamic mathematical model of the hybrid scheme with variables expressed in d - q synchronous reference frame has been developed. The model is implemented in the SimpowerTM platform, the simulation results bring out the usefulness of hybrid operation of PV, and wind-driven IG for grid connected operations. (authors)

  14. Model Building of Photovoltaic Array with MPPT Function and Research on Single Phase Grid Connected

    OpenAIRE

    Li Zhengzhou

    2016-01-01

    With the continued development of solar photovoltaic technology, research on distributed grid connected photovoltaic system has become a research focus in the field of photovoltaic grid power plant and the computer simulation technology is an effective technology means in the study. On the basis of the photovoltaic array output characteristic equation, the photovoltaic array maximum power control simulation model based on M function is established by using MATLAB/Simulink and the simulation m...

  15. Real Time Photovoltaic Array Simulator for Testing Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sera, Dezso; Valentini, Massimo; Raducu, Alin

    2008-01-01

    In this paper a real time flexible PV array simulator is presented. It is a system that can simulate different PV panel arrays in specific environmental conditions. To evaluate performance of the Maximum Power Point Tracking (MPPT) of grid-connected Photovoltaic (PV) inverters only measurements...

  16. Model Building of Photovoltaic Array with MPPT Function and Research on Single Phase Grid Connected

    Directory of Open Access Journals (Sweden)

    Li Zhengzhou

    2016-01-01

    Full Text Available With the continued development of solar photovoltaic technology, research on distributed grid connected photovoltaic system has become a research focus in the field of photovoltaic grid power plant and the computer simulation technology is an effective technology means in the study. On the basis of the photovoltaic array output characteristic equation, the photovoltaic array maximum power control simulation model based on M function is established by using MATLAB/Simulink and the simulation model of single phase grid connected photovoltaic array is proposed. It overcomes the shortcomings of the process of building the model of the PV array by using Simulink component library and provides the basic guarantee for the realization of system simulation, guiding theory research and system design.

  17. Waveguide-coupled micro-ball lens array suitable for mass fabrication

    NARCIS (Netherlands)

    Chang, Lantian; Dijkstra, Meindert; Ismail, Nur; Pollnau, Markus; Ridder, de René M.; Wörhoff, Kerstin; Subramaniam, Vinod; Kanger, Johannes S.

    2015-01-01

    We demonstrate a fabrication procedure for the direct integration of micro-ball lenses on planar integrated optical channel waveguide chips with the aim to reduce the divergence of light that arises from the waveguide in both horizontal and vertical directions. Fabrication of the lenses is based on

  18. Ball cocks for subsurface installation for utilization in district heating grids; Erdeinbau-Kugelhaehne fuer den Einsatz in Fernwaerme-Netzen

    Energy Technology Data Exchange (ETDEWEB)

    Burg, Albert

    2009-07-01

    As shut-off valves in buried pipelines, ball cocks are used almost exclusively. The rated caliber is between DN 20 and DN 1000. The problem in district heating grids consists in the fact that shut-off valves are operated only in case of emergencies or during grid extensions, but it is very important that they function reliably in these critical conditions even after a life of 30 years. Another problem in district heating grids is the fact that the flow direction can be reversed, depending on the mode of operation of the grid. Fittings therefore must provide tight sealing on both sides. The contribution lists potential causes of damage and proposes countermeasures and preventive measures. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kittle, David; Holshouser, Barbara; Slater, James M.; Guenther, Bob D.; Pitsianis, Nikos P.; Pearlstein, Robert D. [Department of Radiation Medicine, Epilepsy Radiosurgery Research Program, Loma Linda University, Loma Linda, California 92354 (United States); Department of Radiology, Loma Linda University Medical Center, Loma Linda, California 92354 (United States); Department of Radiation Medicine, Loma Linda University, Loma Linda, California 92354 (United States); Department of Physics, Duke University, Durham, North Carolina 27708 (United States); Department of Electrical and Computer Engineering and Department of Computer Science, Duke University, Durham, North Carolina 27708 (United States); Department of Radiation Medicine, Epilepsy Radiosurgery Research Program, Loma Linda University, Loma Linda, California 92354 and Department of Surgery-Neurosurgery, Duke University and Medical Center, Durham, North Carolina 27710 (United States)

    2008-12-15

    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{sup 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.

  20. Model-grid and hydraulic-property data arrays of the MULT package of the Central Valley Hydrologic Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset defines the model-grid and hydraulic-property data arrays of the Multiplier (MULT) Package used in the transient hydrologic model of the...

  1. Research of improved sparse grid non-uniformity correction technologies for infrared resistor array

    Science.gov (United States)

    Du, Hui-jie; Zhao, Hong-ming; Gao, Yang; Yu, Hong; Zhang, Yi

    2015-10-01

    Infrared resistor arrays perform a vital role in the hardware in the loop testing of infrared seekers. Infrared resistor arrays composed of large numbers of suspended resistor elements are commonly used to produce dynamic two-dimensional images of infrared radiation. Due to inconsistencies in the fabrication process of the resistor arrays, the temperature each resistor elements reaches for a given input voltage is variable and this leads to more significant radiance differences, these differences result in spatially-distributed radiance non-uniformity. Therefore, in order to obtain an available infrared image, non-uniformity correction (NUC) is necessary. In this paper, the non-uniformity characters of the infrared resistor arrays are analyzed base on measured data and then an improved sparse grid method for engineering are discussed and analyzed. First of all, the NUC camera has a strong influence on the effectiveness of the infrared resistor arrays NUC procedure. According to the actual fact and the laboratory condition, we presented an alternative method for collecting resistor arrays intended to reduce the influence causing by the NUC camera. Secondly, based on the measured non-uniformity data, we obtain the response characteristics of the infrared resistor arrays. In each gray level, we take two points or several points correction algorithm to calculate the gain data and the offset data, and then the linear look-up table is established. Finally, through MATLAB we develop the correction software, and we can obtain the driving output conveniently. The result shows that the image quality has a remarkable improvement after non-uniformity correction, the non-uniformity correction flow and algorithm preferably satisfies the requirement of the high confidence infrared imaging simulation.

  2. Efficiency calibration and coincidence summing correction for large arrays of NaI(Tl) detectors in soccer-ball and castle geometries

    Energy Technology Data Exchange (ETDEWEB)

    Anil Kumar, G., E-mail: anilg@tifr.res.i [Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India); Mazumdar, I.; Gothe, D.A. [Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

    2009-11-21

    Efficiency calibration and coincidence summing correction have been performed for two large arrays of NaI(Tl) detectors in two different configurations. They are, a compact array of 32 conical detectors of pentagonal and hexagonal shapes in soccer-ball geometry and an array of 14 straight hexagonal NaI(Tl) detectors in castle geometry. Both of these arrays provide a large solid angle of detection, leading to considerable coincidence summing of gamma rays. The present work aims to understand the effect of coincidence summing of gamma rays while determining the energy dependence of efficiencies of these two arrays. We have carried out extensive GEANT4 simulations with radio-nuclides that decay with a two-step cascade, considering both arrays in their realistic geometries. The absolute efficiencies have been simulated for gamma energies from 700 to 2800 keV using four different double-photon emitters, namely, {sup 60}Co, {sup 46}Sc, {sup 94}Nb and {sup 24}Na. The efficiencies so obtained have been corrected for coincidence summing using the method proposed by Vidmar et al. . The simulations have also been carried out for the same energies assuming mono-energetic point sources, for comparison. Experimental measurements have also been carried out using calibrated point sources of {sup 137}Cs and {sup 60}Co. The simulated and the experimental results are found to be in good agreement. This demonstrates the reliability of the correction method for efficiency calibration of two large arrays in very different configurations.

  3. A Comparative Study of Inspection Techniques for Array Packages

    Science.gov (United States)

    Mohammed, Jelila; Green, Christopher

    2008-01-01

    This viewgraph presentation reviews the inspection techniques for Column Grid Array (CGA) packages. The CGA is a method of chip scale packaging using high temperature solder columns to attach part to board. It is becoming more popular over other techniques (i.e. quad flat pack (QFP) or ball grid array (BGA)). However there are environmental stresses and workmanship challenges that require good inspection techniques for these packages.

  4. Holy balls!

    OpenAIRE

    Wright, Michael; Langley, Ken; Belden, Jesse; Truscott, Tadd

    2011-01-01

    We demonstrate the behavior of three balls skipping off of the water surface: a Superball, a racquetball, and a water bouncing ball (Waboba). The three balls have rebound coefficients of 0.9, 0.8 and 0.2, respectively. However, we notice that the Waboba bounces better than the others, but why? The Superball has a high coefficient of restitution, creating large rebounds. Here the impact is angled to the free surface, but the inelastic response and large mass ratio forces the ball underwater wi...

  5. Coplanarity inspection of BGA solder balls based on laser interference structure light

    Science.gov (United States)

    Wei, Zhe; Xiao, Zexin; Zhang, Xuefei; Zhou, Haiying

    2011-11-01

    Using laser interference structure light for profilometry is a rapid, non-contact, full-field profile and high accuracy measuring method.And it has been a promising technique in complicated geometrical shape measurement. In this paper, a fast and cost-effective measurement method of coplanarity inspection of ball grid array (BGA) solder balls is proposed. Laser interference structure light can be obtained by using the principle of shearing interferometry. The collimated and beam expanded laser produced interference fringe by the high reflection rate optical flat. After laser interference fringe project on the surface of object and the structured light would modulated. The light signal pass through the image optical grabber and captured by the CCD image sensor. The height of each point on object can be demodulated by the imaging processing software.This method to construct the measurement appliance for coplanarity inspection of ball grid array (BGA) chip solder ball. Experiments have shown that the coplanarity measurement of BGA solder balls is very efficient and effective with the measurement. The measurement accuracy achieve micrometer level. The processing time of the measurement accuracy is less than 3s on a personal computer. This measurement appliance could completely meet the demand of measure.

  6. Array of virtual Frisch-grid CZT detectors with common cathode readout and pulse-height correction

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Egarievwe, E.U.; Fochuk, P.M.; Fuerstnau, M.; Gul, R.; Hossain, A.; Jones, F.; Kim, K.; Kopach, O.V.; Taggart, R.; Yang, G.; Ye, Z.; Xu, L.; and James, R.B.

    2010-08-01

    We present our new results from testing 15-mm-long virtual Frisch-grid CdZnTe detectors with a common-cathode readout for correcting pulse-height distortions. The array employs parallelepiped-shaped CdZnTe (CZT) detectors of a large geometrical aspect ratio, with two planar contacts on the top and bottom surfaces (anode and cathode) and an additional shielding electrode on the crystal's sides to create the virtual Frisch-grid effect. We optimized the geometry of the device and improved its spectral response. We found that reducing to 5 mm the length of the shielding electrode placed next to the anode had no adverse effects on the device's performance. At the same time, this allowed corrections for electron loss by reading the cathode signals to obtain depth information.

  7. Holy balls!

    Science.gov (United States)

    Truscott, Tadd; Belden, Jesse

    2011-11-01

    Why can some balls walk on water while others cannot? We investigate the rebound dynamics of elastic spheres impacting on a free-surface. Several variables determine whether or not a sphere will bounce when impacting a free-surface including velocity, impact angle, size and elasticity. Stiff elastic spheres, such as a racquetball, successfully skip at low impact angles and high velocities, but tend not to bounce when the impact angle becomes too large. However, the more compliant Waboba (WAter BOuncing BAll) bounces marvelously even at very high impact angles. Unlike a stiffer ball, the Waboba flattens out quickly as it is forming a cavity. The cavity lip forms a ramp and the flattened ball then skips off the water surface. We demonstrate how this phenomenon surprisingly resembles a skipping stone. Using high-speed video we explore the rebound dynamics for various values of elasticity, velocity, angle and size and determine when an object will bounce off the water surface.

  8. Golf Ball

    Science.gov (United States)

    1998-01-01

    The Ultra 500 Series golf balls, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides 'the most symmetrical ball surface available, sustaining initial velocity longer and producing the most stable ball flight for unmatched accuracy and distance.' The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the ball flight and the medium size dimples blend the other two.

  9. Break-up Process of Perturbed Molten Metal Jet and Preparation of Lead-Free Solder Balls

    Institute of Scientific and Technical Information of China (English)

    He Lijun; Zhang Shuguang; Zhang Shaoming; Xu Jun; Shi Likai

    2004-01-01

    Solder balls, which are used in advanced electronics packages such as BGA (Ball Grid Array) and CSP (Chip Scale Package) to substitute the leads and realize the electrical and mechanical connections between substrate and chip,have severe specifications in diameter tolerance, roundness and surface quality, and therefore challenge the traditional technologies for fabrication of metallic particles and powders. The present work made a survey of perturbed molten metal jet break-up process, observed the formation and growth of capillary wave of tin-lead melt jet by way of rapid solidification, and on the basis of the above research, successfully obtained tin-lead eutectic and Sn-4.0Ag-0.5Cu lead free solder balls with tight distribution and good sphericity of particles through optimization of processing parameters, forming a solid base for cost effectively producing solder balls.

  10. 2-D Row-Column CMUT Arrays with an Open-Grid Support Structure

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Dahl-Petersen, Christian; Jensen, Jørgen Arendt;

    2013-01-01

    Fabrication and characterization of 64 + 64 2-D row-column addressed CMUT arrays with 250 μm element pitch and 4.4 MHz center frequency in air incorporating a new design approach is presented. The arrays are comprised of two wafer bonded, structured silicon-on-insulator wafers featuring an opengrid...... support structure on top of the CMUT plates, omitting the need for through wafer vias. A 5 mask process is used to produce 2-D row-column addressed CMUT arrays with 74 nm vacuum gaps, single crystalline silicon plates with optional lithographically defined mass loads, 120 V pull-in voltage, and high...

  11. Holy balls!

    CERN Document Server

    Wright, Michael; Belden, Jesse; Truscott, Tadd

    2011-01-01

    We demonstrate the behavior of three balls skipping off of the water surface: a Superball, a racquetball, and a water bouncing ball (Waboba). The three balls have rebound coefficients of 0.9, 0.8 and 0.2, respectively. However, we notice that the Waboba bounces better than the others, but why? The Superball has a high coefficient of restitution, creating large rebounds. Here the impact is angled to the free surface, but the inelastic response and large mass ratio forces the ball underwater without skipping. The racquetball has a lower mass ratio and a more elastic response to impacts. Also thrown at a shallow angle, it bounces off of the surface of the water 1-3 times before coming to rest. The Waboba flattens inside the cavity allowing it to skip off of the surface more easily. The flattened ball looks more like a skipping stone than a sphere due to its large elastic deformation at impact. Examining the reaction of a skipping stone we see that the stone creates a cavity in which it planes, slipping out of it...

  12. 再成形(Re-Balled)焊球阵列封装的焊球强度评估%Solder Ball Attachment Assessment of Reballed Plastic Ball Grid Array Packages

    Institute of Scientific and Technical Information of China (English)

    Lei Nie; Michael Osterman; Michael Pecht; Fubin Song; Jeffrey Lo; S.W.Ricky Lee

    2009-01-01

    近年来,许多国家禁止在电子产品中铅的使用,但是一些特定产品拥有豁免权.拥有豁免权的电子产品生产厂商面临含铅元器件供应缺乏的现状,因此生产厂商开始寻求利用焊球再成形技术把焊球阵列封装中的无铅焊球转变为锡铅焊球.焊球再成形技术曾经被用于元器件的回收再利用,但是关于焊球再成形元器件的可靠性信息十分有限.介绍了利用焊球再成形技术使无铅焊球阵列封装转变为锡铅焊球阵列封装.两种焊球去除方法和两种焊球再贴装方法分别用于实现从无铅焊球到锡铅焊球的转变,用以调查再成形工艺对于封装质量的影响.热时效试验以及焊球强度评估用于检测焊球再成形工艺过程.

  13. A versatile sensor performance evaluation platform with an impactor-inspired sample chamber and virtual pin grid array

    International Nuclear Information System (INIS)

    We present the details necessary for building a scalable, flexible, and universal sensor performance evaluation platform with an impactor-inspired sample chamber and a virtual pin grid array for maintaining electrical connections. The system is designed to accommodate a wide range of sensors varying in physical dimensions, electrical connections, and transduction mechanisms. By integrating a switch matrix system with a commercial chip carrier, we have built a platform for rapidly screening sensors for promise in military, homeland security, and commercial applications without requiring custom circuits or packages for each sensor technology. Intuitive, graphical software is written and provided to control and monitor temperature, flow rate, and electrical connections. The system is capable of operating and interfacing with a variety of vapor delivery systems for chemical vapor detection measurements of emerging sensor technologies. (paper)

  14. Science of Ball Lightning (Fire Ball)

    Science.gov (United States)

    Ohtsuki, Yoshi-Hiko

    1989-08-01

    The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Ball Lightning -- The Continuing Challenge * Hungarian Ball Lightning Observations in 1987 * Nature of Ball Lightning in Japan * Phenomenological and Psychological Analysis of 150 Austrian Ball Lightning Reports * Physical Problems and Physical Properties of Ball Lightning * Statistical Analysis of the Ball Lightning Properties * A Fluid-Dynamical Model for Ball Lightning and Bead Lightning * The Lifetime of Hill's Vortex * Electrical and Radiative Properties of Ball Lightning * The Candle Flame as a Model of Ball Lightning * A Model for Ball Lightning * The High-Temperature Physico-Chemical Processes in the Lightning Storm Atmosphere (A Physico-Chemical Model of Ball Lightning) * New Approach to Ball Lightning * A Calculation of Electric Field of Ball Lightning * The Physical Explanation to the UFO over Xinjiang, Northern West China * Electric Reconnection, Critical Ionization Velocity, Ponderomotive Force, and Their Applications to Triggered and Ball Lightning * The PLASMAK™ Configuration and Ball Lightning * Experimental Research on Ball Lightning * Performance of High-Voltage Test Facility Designed for Investigation of Ball Lightning * List of Participants

  15. A New Method of PV Array Faults Diagnosis in Smart Grid

    Directory of Open Access Journals (Sweden)

    Ze Cheng

    2014-01-01

    Full Text Available A new fault diagnosis method is proposed for PV arrays with SP connection in this study, the advantages of which are that it would minimize the number of sensors needed and that the accuracy and anti-interference ability are improved with the introduction of fuzzy group decision-making theory. We considered five “decision makers” contributing to the diagnosis of PV array faults, including voltage, current, environmental temperature, panel temperature, and solar illumination. The accuracy and reliability of the proposed method were verified experimentally, and the possible factors contributing to diagnosis deviation were analyzed, based on which solutions were suggested to reduce or eliminate errors in aspects of hardware and software.

  16. Hydrodynamics of triangular-grid arrays of floating point-absorber wave energy converters with inter-body and bottom slack-mooring connections

    Energy Technology Data Exchange (ETDEWEB)

    Vicente, Pedro C.; Falcao, Antonio F. de O.; Gato, Luiz M.C. [IDMEC, Instituto Superior Tecnico, Technical University of Lisbon, 1049-001 Lisboa (Portugal); Justino, Paulo A.P. [Laboratorio Nacional de Energia e Geologia, 1649-038 Lisboa (Portugal)

    2009-07-01

    It may be convenient that dense arrays of floating point absorbers are spread-moored to the sea bottom through only some of their elements (possibly located in the periphery), while the other array elements are prevented from drifting and colliding with each other by connections to adjacent elements. An array of identical floating point absorbers located at the grid points of an equilateral triangular grid is considered in the paper. A spread set of slack-mooring lines connect the peripheric floaters to the bottom. A weight is located at the centre of each triangle whose function is o pull the three floaters towards each other and keep the inter-body moorings lines under tension. The whole system - buoys, moorings and power take-off systems - is assumed linear, so that a frequency domain analysis may be employed. Hydrodynamic interference between the oscillating bodies is neglected. Equations are presented for a set of three identical point absorbers. This is then extended to more complex equilateral iriangular grid arrays. Results from numerical simulations, with regular and irregular waves, are presented for the motions and power absorption of hemispherical converters in arrays of three and seven elements and different mooring and power take-off parameters, and wave incidence angles. Comparisons are given with the unmoored and independently-moored buoy situations.

  17. Impact study of the Argo array definition in the Mediterranean Sea based on satellite altimetry gridded data

    Science.gov (United States)

    Sanchez-Roman, Antonio; Ruiz, Simón; Pascual, Ananda; Guinehut, Stéphanie; Mourre, Baptiste

    2016-04-01

    The existing Argo network provides essential data in near real time to constrain monitoring and forecasting centers and strongly complements the observations of the ocean surface from space. The comparison of Sea Level Anomalies (SLA) provided by satellite altimeters with in-situ Dynamic Heights Anomalies (DHA) derived from the temperature and salinity profiles of Argo floats contribute to better characterize the error budget associated with the altimeter observations. In this work, performed in the frame of the E-AIMS FP7 European Project, we focus on the Argo observing system in the Mediterranean Sea and its impact on SLA fields provided by satellite altimetry measurements in the basin. Namely, we focus on the sensitivity of specific SLA gridded merged products provided by AVISO in the Mediterranean to the reference depth (400 or 900 dbar) selected in the computation of the Argo Dynamic Height (DH) as an integration of the Argo T/S profiles through the water column. This reference depth will have impact on the number of valid Argo profiles and therefore on their temporal sampling and the coverage by the network used to compare with altimeter data. To compare both datasets, altimeter grids and synthetic climatologies used to compute DHA were spatially and temporally interpolated at the position and time of each in-situ Argo profile by a mapping method based on an optimal interpolation scheme. The analysis was conducted in the entire Mediterranean Sea and different sub-regions of the basin. The second part of this work is devoted to investigate which configuration in terms of spatial sampling of the Argo array in the Mediterranean will properly reproduce the mesoscale dynamics in this basin, which is comprehensively captured by new standards of specific altimeter products for this region. To do that, several Observing System Simulation Experiments (OSSEs) were conducted assuming that altimetry data computed from AVISO specific reanalysis gridded merged product for

  18. Berkeley High-Resolution Ball

    International Nuclear Information System (INIS)

    Criteria for a high-resolution γ-ray system are discussed. Desirable properties are high resolution, good response function, and moderate solid angle so as to achieve not only double- but triple-coincidences with good statistics. The Berkeley High-Resolution Ball involved the first use of bismuth germanate (BGO) for anti-Compton shield for Ge detectors. The resulting compact shield permitted rather close packing of 21 detectors around a target. In addition, a small central BGO ball gives the total γ-ray energy and multiplicity, as well as the angular pattern of the γ rays. The 21-detector array is nearly complete, and the central ball has been designed, but not yet constructed. First results taken with 9 detector modules are shown for the nucleus 156Er. The complex decay scheme indicates a transition from collective rotation (prolate shape) to single- particle states (possibly oblate) near spin 30 h, and has other interesting features

  19. Having a Ball with Fitness Balls

    Science.gov (United States)

    McNulty, Betty

    2011-01-01

    Fitness programs can be greatly enhanced with the addition of fitness balls. They are a fun, challenging, economical, and safe way to incorporate a cardiovascular, strength, and stretching program for all fitness levels in a physical education setting. The use of these balls has become more popular during the last decade, and their benefits and…

  20. Actuated Ball Sports

    OpenAIRE

    Clerix, Ben

    2015-01-01

    Ball sports offer many physical, mental and social benefits, however they each require a different set of attributes, such as basketball hoops, volleyball nets, bowling pins, etc. Thus in order to play each of these ball sports, we need to provide and manually set up each of different attributes. Digital ball sports on the other hand virtualise these different attributes at the cost of losing physicality, however they have the possibility to create non-realistic experiences. Without physicali...

  1. Physics of ball sports

    Science.gov (United States)

    Cohen, C.; Clanet, C.

    2016-06-01

    Ball sports have been part of human history for thousands of years [1]. Nowadays, 13 of them are part of the Olympic games (badminton, basketball, beach volley, football/soccer, golf, handball, hockey, rugby, table tennis, tennis, volleyball, water polo, ice hockey). All these games differ by launcher (hand, club, racket, bat), ball (size, shape and mass), pitch size and number of players. These differences induce different ball velocities. Apart from the velocities and the way to maximize them, we discuss in this article the ball trajectories and their impact on the size of sports fields.

  2. 基于嵌入式Linux平台的球栅尺数显表设计%Design of DRO of Ball Grid Scale Based on Embedded Linux Platform

    Institute of Scientific and Technical Information of China (English)

    穆小川; 胡剑凌; 翁路成; 殷开亮

    2014-01-01

    球栅尺数显表是一种测量球栅尺输出,并计算、显示位移的仪表。文中设计了一款液晶显示的、基于嵌入式Linux平台的多通道高性能球栅尺数显表,该数显表采用基于Cortex A8内核的AM3517为主处理器,FPGA为协处理器的架构方式,设计了基于Qt的图形用户界面。所设计的数显表同时支持4路模拟或数字球栅尺读数头的输入,并且各路读数头的参数可通过图形用户界面独立地进行在线配置。测试结果表明,所设计的多通道数显表可以达到1μm分辨率,测量误差在±10μm范围内,且数值显示稳定,跟踪速度快,支持零点搜索和掉电自动追数等多种实用功能,同时用户交互界面友好,满足高精度数控机床的应用需求。%A digital readout system ( DRO) is an instrument which generates the excitation signal for ball grid scale and receives the re-sponse signal. Then the displacement is calculated and displaced by the DRO according to the received signal. In this paper,a multi-chan-nel high-performance DRO based on embedded Linux platform is presented,where LCD is selected as the display device. The DRO a-dopts a framework of ARM plus FPGA,where AM3517 with Cortex A8 core is acted as the main processor and FPGA works as a copro-cessor. Also a graphical user interface based on Qt is implemented. The designed DRO can drive four reading heads,and each reading head can be analog or digital. The parameters of each reading head can be configured independently through a graphical user interface on-line. Test results show that the designed DRO has display resolution of 1 um and the measurement error is limited between-10 um and 10 um. The numerical display of DRO is stable and can track the rapid movement of the scale. The designed DRO supports a variety of useful features,such as zero search and automatic recovery from unexpected power down. Besides the DRO also has a friendly user interface. All these features meet the

  3. Ball Collision Experiments

    Science.gov (United States)

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  4. Borner Ball Neutron Detector

    Science.gov (United States)

    2002-01-01

    The Bonner Ball Neutron Detector measures neutron radiation. Neutrons are uncharged atomic particles that have the ability to penetrate living tissues, harming human beings in space. The Bonner Ball Neutron Detector is one of three radiation experiments during Expedition Two. The others are the Phantom Torso and Dosimetric Mapping.

  5. Distance Geometry for Kissing Balls

    CERN Document Server

    Chen, Hao

    2012-01-01

    A kissing ball is a ball that is tangent to a fixed reference ball. In this paper, we will treat kissing balls with techniques from the Euclidean distance geometry. This turns out to be more general than the classical Euclidean distance geometry. We will show that the distance matrix for the kissing balls plays, at the same time, the role of Cayley-Menger matrix. Thus classical problems in Euclidean distance geometry will have new versions for kissing balls.

  6. Happy Balls, Unhappy Balls, and Newton's Cradle

    Science.gov (United States)

    Kagan, David

    2010-01-01

    The intricacies of Newton's Cradle are well covered in the literature going as far back as the time of Newton! These discussions generally center on the highly elastic collisions of metal spheres. Thanks to the invention of happy and unhappy balls, you can build and study the interaction of less elastic systems (see Fig. 1).

  7. Compact Q-balls

    CERN Document Server

    Bazeia, D; Marques, M A; Menezes, R; da Rocha, R

    2016-01-01

    In this work we deal with non-topological solutions of the Q-ball type in two space-time dimensions, in models described by a single complex scalar field that engenders global symmetry. The main novelty is the presence of stable Q-balls solutions that live in a compact interval of the real line and appear from a family of models controlled by two distinct parameters. We find analytical solutions and study their charge and energy, and show how to control the parameters to make the Q-balls classically and quantum mechanically stable.

  8. Theory of ball lightning

    CERN Document Server

    Wu, H -C

    2014-01-01

    We present a comprehensive explanation on ball lightning, a luminous sphere occasionally witnessed after ordinary lightning. In the last decade, it has been well established that natural lightning routinely generates relativistic electrons, which account for observed x rays. So we assume that, in a ball lightning event, a well-defined relativistic electron bunch is produced by the stepped leader of lightning. When this electron bunch strikes various media, a powerful microwave pulse is emitted by the coherent transition radiation mechanism. This intense microwave ionizes air, evacuates plasmas by its radiation pressure to form a globular plasma cavity, and then gets trapped inside the cavity. This theory successfully explains all characteristics of ball lightning, especially the appearance of ball lightning in fully-screened aircraft. Moreover, the proposed radiation mechanism fully explains the strongest radio signals from lightning and nanosecond spikes in the signals are direct evidences on the generation ...

  9. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    1985-01-01

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  10. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  11. A Wireless and Batteryless Microsystem with Implantable Grid Electrode/3-Dimensional Probe Array for ECoG and Extracellular Neural Recording in Rats

    Directory of Open Access Journals (Sweden)

    Chih-Wei Chang

    2013-04-01

    Full Text Available This paper presents the design and implementation of an integrated wireless microsystem platform that provides the possibility to support versatile implantable neural sensing devices in free laboratory rats. Inductive coupled coils with low dropout regulator design allows true long-term recording without limitation of battery capacity. A 16-channel analog front end chip located on the headstage is designed for high channel account neural signal conditioning with low current consumption and noise. Two types of implantable electrodes including grid electrode and 3D probe array are also presented for brain surface recording and 3D biopotential acquisition in the implanted target volume of tissue. The overall system consumes less than 20 mA with small form factor, 3.9 × 3.9 cm2 mainboard and 1.8 × 3.4 cm2 headstage, is packaged into a backpack for rats. Practical in vivo recordings including auditory response, brain resection tissue and PZT-induced seizures recording demonstrate the correct function of the proposed microsystem. Presented achievements addressed the aforementioned properties by combining MEMS neural sensors, low-power circuit designs and commercial chips into system-level integration.

  12. The bowling balls

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    10 November 1972: CERN’s Bent Stumpe places an order for 12 bowling balls for a total cost of 95 US dollars. Although not evident at first sight, he is buying the heart of some of the first tracking devices to be used in the SPS control room. Today, Bent Stumpe’s device would be called a desktop mouse…   The first order for 4 bowling balls later changed to 12 balls. The bowling balls became the heart of Bent Stumpe's mouse. Almost 40 years ago, the web, Wikipedia and Google did not exist and it was much more difficult to know whether other people in other parts of the world or even in the same laboratory were facing the same problems or developing the same tools. At that time, Bent Stumpe was an electronics engineer, newly recruited to work on developments for the SPS Central Control room. One of the things his supervisor asked him to build as soon as possible was a device to control a pointer on a screen, also called a tracker ball. The heart of the device was the...

  13. Tunguska Dark Matter Ball

    CERN Document Server

    Froggatt, C D

    2014-01-01

    It is suggested that the Tunguska event in June 1908 cm-large was due to a cm-large ball of a condensate of bound states of 6 top and 6 anti-top quarks containing highly compressed ordinary matter. Such balls are supposed to make up the dark matter as we earlier proposed. The expected rate of impact of this kind of dark matter ball with the earth seems to crudely match a time scale of 200 years between the impacts. The main explosion of the Tunguska event is explained in our picture as material coming out from deep within the earth, where it has been heated and compressed by the ball penetrating to a depth of several thousand km. Thus the effect has some similarity with volcanic activity as suggested by Kundt. We discuss the possible identification of kimberlite pipes with earlier Tunguska-like events. A discussion of how the dark matter balls may have formed in the early universe is also given.

  14. Calculations and Analysis of the Triangle-grid Taylor and Bayliss Circular-aperture Phased Array Antenna%三角形栅格圆口径平面相控阵天线的分析计算

    Institute of Scientific and Technical Information of China (English)

    袁汉钦; 陈玺羽

    2014-01-01

    以矩形栅格和三角形栅格的圆口径天线的方向图进行了计算研究,首先给出了三角形栅格圆口径平面阵的模型,依据模型计算出在使用三角形栅格时能有效减少阵元数量;首次计算了圆口径三角形栅格的泰勒加权和方向图和贝利斯加权差方向图,为工程应用提供了依据。%This paper researches on the pattern of the circular-aperture phased array antenna for the rec-tangle and triangle grid. Firstly,the model for triangle-grid circular-aperture is given. According to the model,the calculating results show that the elements of the array antenna are saved by applying the trian-gle-grid in circular-apetures antenna. The paper primarily studies the pattern of the triangle-grid Taylor and Bayliss circular-aperture,which can be the reference for the practical application.

  15. Have a Ball

    Institute of Scientific and Technical Information of China (English)

    程炜

    2003-01-01

    Before being sent to prison Carl drove big cars and ate in expensive restaurants. No one knew where he got his money but he was certainly having a ball. When the judge sentenced him.to prison he said, “I hope you have a bail, Carl.” To have a bait is to have a wonderful time.

  16. An array of virtual Frisch-grid CdZnTe detectors and a front-end application-specific integrated circuit for large-area position-sensitive gamma-ray cameras.

    Science.gov (United States)

    Bolotnikov, A E; Ackley, K; Camarda, G S; Cherches, C; Cui, Y; De Geronimo, G; Fried, J; Hodges, D; Hossain, A; Lee, W; Mahler, G; Maritato, M; Petryk, M; Roy, U; Salwen, C; Vernon, E; Yang, G; James, R B

    2015-07-01

    We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm(3) detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays' performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.

  17. An array of virtual Frisch-grid CdZnTe detectors and a front-end application-specific integrated circuit for large-area position-sensitive gamma-ray cameras

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, A. E., E-mail: bolotnik@bnl.gov; Ackley, K.; Camarda, G. S.; Cherches, C.; Cui, Y.; De Geronimo, G.; Fried, J.; Hossain, A.; Mahler, G.; Maritato, M.; Roy, U.; Salwen, C.; Vernon, E.; Yang, G.; James, R. B. [Brookhaven National Laboratory, Upton, New York 11793 (United States); Hodges, D. [University of Texas at El Paso, El Paso, Texas 79968 (United States); Lee, W. [Korea University, Seoul 136-855 (Korea, Republic of); Petryk, M. [SUNY Binghamton, Vestal, New York 13902 (United States)

    2015-07-15

    We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm{sup 3} detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays’ performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.

  18. An array of virtual Frisch-grid CdZnTe detectors and a front-end application-specific integrated circuit for large-area position-sensitive gamma-ray cameras

    International Nuclear Information System (INIS)

    We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm3 detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays’ performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects

  19. A Fast MoM Calculation Technique Using Sinusoidal Basis and Testing Functions for a Wire on a Dielectric Substrate and Its Application to Meander Loop and Grid Array Antennas

    OpenAIRE

    Nakano, Hisamatsu; Kawano, Toru; Kozono, Yousuke; Yamauchi, Junji

    2005-01-01

    The input impedance matrix element of the method of moments (MoM) for an arbitrarily shaped wire antenna printed on a dielectric material Zm,n is formulated to be composed of three terms Zψsm,n, Zψm,n, and ΔZm,n involving single-, double-, and triple-integral calculations, respectively. The MoM based on the Zm,n formulated in this paper (new MoM) is applied to two antennas-a meander loop antenna and a grid array antenna-as well as a simple loop used as a reference antenna. The computation tim...

  20. BLEACHING NEPTUNE BALLS

    Directory of Open Access Journals (Sweden)

    BONET Maria Angeles

    2014-05-01

    Full Text Available Posidonia Oceanic is a seaweed from Mediterranean Sea and it is more concentrated at the Balerian SEA. This implies the Valencian Community also. It forms vaste underwater meadows in the sea and are part of the Mediterranean ecosystem. It is a sea-grass specie with fruits and flowers. Leaves are ribbon-like and they grow in winter and at the end of summer some of them are separated and arrive to some sea line. Fuit is separated and can floate, it is known as “the olive of the sea” mainly in Italy, or as the Neptune Balls. As it can be used in different fields, it is is being studied in order ro have the precitice tests. Some authors have reported the manufacturing of fully bio-based comites with a gluten matrix by hot-press molding. And it has been considered as an effective insulator for building industry or even though to determine the presence of mercure in the Mediterranean sea some years ago. As many applications can be designed from that fibers, it has been considered to be bleached in order to used them in fashionable products. Consequently, its original brown color is not the most suitable one and it should be bleached as many other cellulosic fibers. The aim of this paper is to bleache neptune balls however, the inner fibers were not accessible at all and it implied not to bleach the inner fibers in the neptune ball. Further studiesd will consider bleaching the individualized fibers.

  1. 交叉潮汐透平阵列能量输出的数值研究%Numerical Study on Power Extractions of Staggered Grid Tidal Turbine Array

    Institute of Scientific and Technical Information of China (English)

    白光辉; 高铁瑜; 李国君

    2012-01-01

    为了使交叉潮汐透平阵列得到更好的应用,针对交叉透平阵列的特性对建立在叶素理论(BE)、激盘模型和计算流体动力学(CFD)技术基础上的计算潮汐透平水动力性能和流场的BE+CFD方法做了进一步的完善.通过该方法深入研究了交叉透平阵列结构参数对阵列透平能量输出特性的影响,结果表明:透平阵列最优横向间距为2.5倍透平叶轮直径;透平阵列纵向间距越大,透平的能量输出越高,纵向间距为6倍透平叶轮直径时,4排交叉透平阵列的相对功率系数可达3.74;最优结构参数时,前两排透平的能量输出较相同条件的单机透平提高了11%.据此,提出了一种新的交叉透平阵列布置方式,经过比较发现,新的交叉透平阵列布置方式较原交叉阵列的优势更为显著,从流场周围吸收的能量更多,透平阵列的能量输出更高.%To obtain better application of staggered grid tidal current turbine array, the BE+CFD method which is based on the blade element theory, the actuator disc model and the CFD technology, and can calculate the hydrodynamic characters and the flow field of tidal current turbines was improved for staggered grid turbine array. Using this method, the influence of staggered grid turbine array' s structural parameters on the power extraction was investigated. The results show that the optimal lateral distance is around 2. 5 times the turbine impeller diameter, and the power extraction increases with the longitudinal distance. The relative power coefficient of the four rows system in this study will reach its maximum value of 3. 74 when the longitudinal distance is 6d. If the system contains only two rows of turbine, the power extraction of the system with optimal layout can be 11% higher than that of the same number stand-alone turbines. In addition, a new layout of staggered grid turbine array is presented according to the results of the analysis. The comparison shows that

  2. Holy Balls!: Part Deux

    Science.gov (United States)

    Belden, Jesse; Jandron, Michael; Truscott, Tadd

    2012-11-01

    A Waboba® (WAter BOuncing BAll) demonstrates remarkable water skipping behavior, even at relatively large impact angles. The highly compliant nature of these elastic spheres results in significant deformation into a disk-like shape upon impact. The increased wetted area and force coefficient generates a large hydrodynamic force that more readily lifts the ball off the water surface. However, elasticity introduces some surprising phenomena, such as material waves that propagate on the sphere and interact with the water cavity. Depending upon impact conditions, material waves may propagate in various directions combining to create multiple modes of deformation and complicated fluid-structure interactions. Furthermore, the timescales of deformation and wave propagation depend on the material properties and impact conditions. In this talk, we will discuss skipping regimes in terms of impact parameters and material properties and relate failed skipping behavior to the structure-fluid interaction caused by deformation. The critical timescales for deformation, wave propagation and collision will be related to the relevant physical parameters of the problem.

  3. High-Performance Ball Bearing

    Science.gov (United States)

    Bursey, Roger W., Jr.; Haluck, David A.; Olinger, John B.; Owen, Samuel S.; Poole, William E.

    1995-01-01

    High-performance bearing features strong, lightweight, self-lubricating cage with self-lubricating liners in ball apertures. Designed to operate at high speed (tens of thousands of revolutions per minute) in cryogenic environment like liquid-oxygen or liquid-hydrogen turbopump. Includes inner race, outer race, and cage keeping bearing balls equally spaced.

  4. Direct Numerical Simulations of the Flow around a Golf Ball: Effect of Rotation

    Science.gov (United States)

    Smith, Clinton; Beratlis, Nikolaos; Squires, Kyle; Balaras, Elias; Tsunoda, Masaya

    2008-11-01

    Golf ball flight is affected by rotation of the ball (lift generation) and dimpling on the surface (drag reduction). Direct Numerical Simulation (DNS) is being developed for the flow around a rotating golf ball using an immersed boundary method. Adding to the computational cost is that the moving body must be re-located as the ball rotates. In the present effort, interface-tracking of the moving body is optimized using the Approximate Nearest Neighbor (ANN) approach. The code is parallelized using domain decomposition and message passing interface (MPI), and parallel performance results are presented for a range of grid sizes. Results are presented from a series of validation cases for flow over a smooth sphere and a golf ball.

  5. Prediction of tar ball formation

    Energy Technology Data Exchange (ETDEWEB)

    Khelifa, A.; Gamble, L. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

    2006-07-01

    The presence of small tar balls ranging in size from less than a millimetre to 60 centimetres have been observed during cleanup assessment operations following accidental oil spills on water. The tar balls are composed of heavy oil residues and suspended particulate matter (SPM) from the water column. They can be found on shorelines, settled on the seafloor and floating at or near the water surface. Their abundance on the shorelines varies from site to site and depends on the conditions of the spill and mixing conditions. Aggregation between SPM and micro-sized oil droplets occurs naturally in coastal waters and enhances the dispersion of spilled oil. Although tar balls are among the important end states of spilled oil in the marine environment, no model exists to estimate the percentage of the spilled oil that becomes tar balls. This paper offered some insight into the modeling of tar ball formation. Current modeling understanding of oil-SPM aggregate formation was used to predict tar ball formation. The formation of oil droplets was examined with respect to a range of conditions under which the formation of large droplets is expected. The role of aggregation was then presented to demonstrate the effects of concentration and type of SPM on the buoyancy of tar balls. Good agreement was found between modeling results and field data reported in the literature regarding the size and density of tar balls. Oil viscosity and mixing energy were found to be the main factors controlling the formation of tar balls. The aggregation of tar balls with SPM and shoreline material results in significant increases or decreases in density, depending on the type and concentration of SPM. 42 refs., 2 tabs., 6 figs.

  6. Method and structure for skewed block-cyclic distribution of lower-dimensional data arrays in higher-dimensional processor grids

    Science.gov (United States)

    Chatterjee, Siddhartha; Gunnels, John A.

    2011-11-08

    A method and structure of distributing elements of an array of data in a computer memory to a specific processor of a multi-dimensional mesh of parallel processors includes designating a distribution of elements of at least a portion of the array to be executed by specific processors in the multi-dimensional mesh of parallel processors. The pattern of the designating includes a cyclical repetitive pattern of the parallel processor mesh, as modified to have a skew in at least one dimension so that both a row of data in the array and a column of data in the array map to respective contiguous groupings of the processors such that a dimension of the contiguous groupings is greater than one.

  7. 关于PBGA中"爆玉米花"现象的分析%Temperature - Dependent Popcorning Analysis of Plastic Ball Grid Array Packaging During Solder Refiow with Fracture Mechanics Mothod

    Institute of Scientific and Technical Information of China (English)

    杨建生; 徐元斌

    2002-01-01

    本文运用断裂力学法分析塑料焊球阵列封装(PBGA)的爆玉米花现象,专门对封装粘片中发生的裂纹,粘片中的裂纹增大以及焊料掩模和铜之间界面处裂纹增大进行研讨,通过两种方法(裂纹尖端开度位移法和有效裂纹闭合技术)确定裂纹尖端参数,诸如应变能释放率,应力强度系数及不同裂纹长度的相角.

  8. Enhancing the Bounce of a Ball

    Science.gov (United States)

    Cross, Rod

    2010-01-01

    In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of…

  9. High Power Fiber Bundle Array Coupled LDA Module

    Institute of Scientific and Technical Information of China (English)

    QU Zhou; LIU Yang; ZHAO Chong-guang; WANG Ji; YIN Hong-he; WANG Li-jun

    2006-01-01

    An optical fiber bundle array coupling module with high output power is presented in this paper. The device integrated the coupling technique of the high power laser diode array (LDA) and the micro-ball lenses fiber array. This module can efficiently couple the output laser of the LDA into 19 fibers array with micro-ball lens endsurface. The difference of the couple efficiency between the flat-end fiber and micro-ball-end fiber is discussed.The micro-ball lenses fiber array made of 19 fibers have the same fiber core diameter of 200 μm, and then the endsurfaces of 19 fibers are fused to 19 micro-ball lenses. The micro-ball lenses fiber array are fixed precisely in the neighborhood on the V-grooves, and the fiber array has the same arrange period with the semiconductor laser units of LDA. This configuration of micro-ball lens fiber array can greatly reduce the divergence of the laser beam from all directions, and a very efficient laser beam homogenizer and shaper are obtained. Finally, high output power of 30.1 W of the fiber coupled LDA is achieved, and the maximal coupling efficiency is >83% with the numeral aperture (NA) of 0.16.

  10. Split-ball resonator

    CERN Document Server

    Kuznetsov, Arseniy I; Fu, Yuan Hsing; Viswanathan, Vignesh; Rahmani, Mohsen; Valuckas, Vytautas; Kivshar, Yuri; Pickard, Daniel S; Lukiyanchuk, Boris

    2014-01-01

    We introduce a new concept of split-ball resonator and demonstrate a strong omnidirectional magnetic dipole response for both gold and silver spherical plasmonic nanoparticles with nanometer-scale cuts. Tunability of the magnetic dipole resonance throughout the visible spectral range is demonstrated by a change of the depth and width of the nanoscale cut. We realize this novel concept experimentally by employing the laser-induced transfer method to produce near-perfect spheres and helium ion beam milling to make cuts with the nanometer resolution. Due to high quality of the spherical particle shape, governed by strong surface tension forces during the laser transfer process, and the clean, straight side walls of the cut made by helium ion milling, magnetic resonance is observed at 600 nm in gold and at 565 nm in silver nanoparticles. Structuring arbitrary features on the surface of ideal spherical resonators with nanoscale dimensions provides new ways of engineering hybrid resonant modes and ultra-high near-f...

  11. Studies On Falling Ball Viscometry

    OpenAIRE

    Singh, Amit Vikram; Sharma, Lavanjay; Gupta-Bhaya, Pinaki

    2012-01-01

    A new method of accurate calculation of the coefficient of viscosity of a test liquid from experimentally measured terminal velocity of a ball falling in the test liquid contained in a narrow tube is described. The calculation requires the value of a multiplicative correction factor to the apparent coefficient of viscosity calculated by substitution of terminal velocity of the falling ball in Stokes formula. This correction factor, the so-called viscosity ratio, a measure of deviation from St...

  12. LHC gets the ball rolling

    CERN Multimedia

    2007-01-01

    A technique involving a small ball with a transmitter embedded inside it has been successfully tested in Sector 7-8. The ball is sent through the LHC beam pipes to check the LHC interconnections. The multidisciplinary team responsible for the RF ball project to check the interconnections. From left to right: Rhodri Jones (AB/BI), Eva Calvo (AB/BI), Francesco Bertinelli (AT/MCS), Sonia Bartolome Jimenez (TS/IC), Sylvain Weisz (TS/IC), Paul Cruikshank (AT/VAC), Willemjan Maan (AT/VAC), Alain Poncet (AT/MCS), Marek Gasior (AB/BI). During the tests the ball is inserted very carefully into the vacuum chamber.A game of ping-pong at the LHC? On 13 September a rather unusual test was carried out in Sector 7-8 of the accelerator. A ball just a bit smaller than a ping-pong ball was carefully introduced into one of the accelerator’s two vacuum pipes, where it travelled 800 metres in the space of a few mi...

  13. Grid Computing

    Indian Academy of Sciences (India)

    2016-05-01

    A computing grid interconnects resources such as high performancecomputers, scientific databases, and computercontrolledscientific instruments of cooperating organizationseach of which is autonomous. It precedes and is quitedifferent from cloud computing, which provides computingresources by vendors to customers on demand. In this article,we describe the grid computing model and enumerate themajor differences between grid and cloud computing.

  14. 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.

  15. Comparison of Field Measurements and EMT Simulation Results on a Multi-Level STATCOM for Grid Integration of London Array Wind Power Plant

    DEFF Research Database (Denmark)

    Glasdam, Jakob; Kocewiak, Łukasz Hubert; Hjerrild, Jesper;

    2014-01-01

    compensator (STATCOM). Quality measurement data allow the system designer to obtain real-life knowledge on the operating characteristics of the electrical component(s) for various operating scenarios of both the OWPP and the external grid. Furthermore, measurement data constitute an indispensable part...... model of the STATCOM with actual field measurements for a commercial MMCC STATCOM. Furthermore, the paper offers the reader, being a researcher, transmission system operator, converter designer or a WPP developer etc., the unique opportunity to gain in-depth knowledge of the operating characteristics...... distortion level. It is found that the total inter-harmonic distortion (TIHD) index calculated according to IEC Standard 61000-4-7 is useful for assessing possible and undesired control interaction between the power electronic devices (PEDs) in OWPPs. The total harmonic distortion (THD) index, on the other...

  16. Comparison of Field Measurements and EMT Simulation Results on a Multi-Level STATCOM for Grid Integration of London Array Wind Farm

    DEFF Research Database (Denmark)

    Glasdam, Jakob Bærholm; Kocewiak, Lukasz; Hjerrild, Jesper;

    2014-01-01

    compensator (STATCOM). Quality measurement data allow the system designer to obtain real-life knowledge on the operating characteristics of the electrical component(s) for various operating scenarios of both the OWPP and the external grid. Furthermore, measurement data constitute an indispensable part...... model of the STATCOM with actual field measurements for a commercial MMCC STATCOM. Furthermore, the paper offers the reader, being a researcher, transmission system operator, converter designer or a WPP developer etc., the unique opportunity to gain in-depth knowledge of the operating characteristics...... distortion level. It is found that the total inter-harmonic distortion (TIHD) index calculated according to IEC Standard 61000-4-7 is useful for assessing possible and undesired control interaction between the power electronic devices (PEDs) in OWPPs. The total harmonic distortion (THD) index, on the other...

  17. MIPP Plastic Ball electronics upgrade

    International Nuclear Information System (INIS)

    An upgrade electronics design for Plastic Ball detector is described. The Plastic Ball detector was a part of several experiments in the past and its back portion (proposed to be used in MIPP) consists of 340 photomultipliers equipped with a sandwich scintillator. The scintillator sandwich has fast and slow signal component with decay times 10 ns and 1 (micro)s respectively. The upgraded MIPP experiment will collect up to 12,000 events during each 4 second spill and read them out in ∼50 seconds between spills. The MIPP data acquisition system will employ deadtime-less concept successfully implemented in Muon Electronics of Dzero experiment at Fermilab. An 8-channel prototype design of the Plastic Ball Front End (PBFE) implementing these requirements is discussed. Details of the schematic design, simulation and prototype test results are discussed.

  18. MIPP Plastic Ball electronics upgrade

    International Nuclear Information System (INIS)

    An upgrade electronics design for Plastic Ball detector is described. The Plastic Ball detector was a part of several experiments in the past and its back portion (proposed to be used in Main Injector Particle Production (MIPP)) consists of 340 photomultipliers equipped with a sandwich scintillator. The scintillator sandwich has fast and slow signal component with decay times 10 ns and 1 μs, respectively. The upgraded MIPP experiment will collect up to 12,000 events during each 4 s spill and read them out in ∼50 s between spills. The MIPP data acquisition system will employ deadtime-less concept successfully implemented in Muon Electronics of Dzero experiment at Fermilab An 8-channel prototype design of the Plastic Ball Front-End (PBFE) implementing these requirements is discussed. Details of the schematic design, simulation and prototype test results are discussed.

  19. Hydraulic-Ball (HY-Ball) Control System

    International Nuclear Information System (INIS)

    The Hy-Ball control system consists of a large number of small tubes vertically penetrating the active core region; the tubes contain movable poison elements (either spherical or cylindrical), which are hydraulically lifted upward from within the active core region to increase core reactivity. Reactor water is the actuating fluid. Hy-Ball columns occupy fuel-element lattice positions in a homogeneous fuel-element configuration. This configuration, with finely subdivided control elements, practically eliminates local water-hole power peaking and provides good control of the radial power distribution. By limitation of the amount of reactivity controlled by a single Hy-Ball column assembly to 0.1% or less, it is unnecessary to operate the poison elements in any position other than either the fully-inserted or fully-withdrawn positions. Elimination of intermediate positions results in simplicity of the system and avoids the inherent axial power perturbation resulting from partially inserted control elements. Physics studies indicate that up to about 40% more power can be obtained from a Hy-Ball-controlled core than from a core with conventional control rods. Tests simulating all reactor operating conditions except radiation are being performed for evaluation of costs, operational characteristics and long-term reliability effects. (author)

  20. Fibonacci Grids

    Science.gov (United States)

    Swinbank, Richard; Purser, James

    2006-01-01

    Recent years have seen a resurgence of interest in a variety of non-standard computational grids for global numerical prediction. The motivation has been to reduce problems associated with the converging meridians and the polar singularities of conventional regular latitude-longitude grids. A further impetus has come from the adoption of massively parallel computers, for which it is necessary to distribute work equitably across the processors; this is more practicable for some non-standard grids. Desirable attributes of a grid for high-order spatial finite differencing are: (i) geometrical regularity; (ii) a homogeneous and approximately isotropic spatial resolution; (iii) a low proportion of the grid points where the numerical procedures require special customization (such as near coordinate singularities or grid edges). One family of grid arrangements which, to our knowledge, has never before been applied to numerical weather prediction, but which appears to offer several technical advantages, are what we shall refer to as "Fibonacci grids". They can be thought of as mathematically ideal generalizations of the patterns occurring naturally in the spiral arrangements of seeds and fruit found in sunflower heads and pineapples (to give two of the many botanical examples). These grids possess virtually uniform and highly isotropic resolution, with an equal area for each grid point. There are only two compact singular regions on a sphere that require customized numerics. We demonstrate the practicality of these grids in shallow water simulations, and discuss the prospects for efficiently using these frameworks in three-dimensional semi-implicit and semi-Lagrangian weather prediction or climate models.

  1. Aligner for Elastic Collisions of Dropped Balls.

    Science.gov (United States)

    Mellen, Walter Roy

    1995-01-01

    Discusses an aligner that permits dropping a stack of any number of balls of different sizes, elasticities, hardnesses, or types to observe the rebound of the top ball. Experimental results allow a reasonable comparison with theory. (MVL)

  2. Silicon Nitride Balls For Cryogenic Bearings

    Science.gov (United States)

    Butner, Myles F.; Ng, Lillian W.

    1990-01-01

    Resistance to wear greater than that of 440C steel. Experiments show lives of ball bearings immersed in liquid nitrogen or liquid oxygen increased significantly when 440C steel balls (running on 440C steel races) replaced by balls of silicon nitride. Developed for use at high temperatures, where lubrication poor or nonexistent. Best wear life of any bearing tested to date and ball material spalls without fracturing. Plans for future tests call for use of liquid oxygen as working fluid.

  3. SECRET OF A BALL LIGHTNING

    Directory of Open Access Journals (Sweden)

    E.V. Savich

    2013-04-01

    Full Text Available A ball lightning is a natural phenomenon that occurs at a streak lightning stroke with its action by thermal and magnetic energy releasing around the streak lightning channel and transforming, in the end, the surrounding air into a steam cloud that transits into ferroelectric state under the magnetic field action.

  4. The correct "ball bearings" data.

    Science.gov (United States)

    Caroni, C

    2002-12-01

    The famous data on fatigue failure times of ball bearings have been quoted incorrectly from Lieblein and Zelen's original paper. The correct data include censored values, as well as non-fatigue failures that must be handled appropriately. They could be described by a mixture of Weibull distributions, corresponding to different modes of failure.

  5. Striking results with bouncing balls

    NARCIS (Netherlands)

    A. Heck; T. Ellermeijer; E. Kędzierska

    2008-01-01

    In a laboratory activity students study the behaviour of a bouncing ball. With the help of a high-speed camera they can study the motion in detail. Computer modelling enables them to relate the measurement results to the theory. They experience that reality (measurements) is not automatically in lin

  6. A Conjecture Concerning Ball Lightning

    CERN Document Server

    Sturrock, P A

    2016-01-01

    There is at present no theory that can explain the curious properties of ball lightning. This suggests that we may not be using the most appropriate concepts. The concept of a 'parallel space' may point the way to a valid theory.

  7. Secrets of the Crystal Ball

    Science.gov (United States)

    Croucher, John S.

    2007-01-01

    This article describes how a crystal ball known as "The Flash Mind Reader" is played. "The Flash Mind Reader" is a mathematics game in which the player is invited to select any-two digit number and then subtract the sum of these two digits from the original number. A chart is provided in which the (adjusted) number they obtained will have a symbol…

  8. Aerodynamics of a golf ball with grooves

    Science.gov (United States)

    Kim, Jooha; Son, Kwangmin; Choi, Haecheon

    2009-11-01

    It is well known that the drag on a dimpled ball is much lower than that on smooth ball. Choi et al. (Phys. Fluids, 2006) showed that turbulence is generated through the instability of shear layer separating from the edge of dimples and delays flow separation. Based on this mechanism, we devise a new golf ball with grooves on the surface but without any dimples. To investigate the aerodynamic performance of this new golf ball, an experiment is conducted in a wind tunnel at the Reynolds numbers of 0.5 x10^5 - 2.7 x10^5 and the spin ratios (ratio of surface velocity to the free-stream velocity) of α=0 - 0.5, which are within the ranges of real golf-ball velocity and spin rate. We measure the drag and lift forces on the grooved ball and compare them with those of smooth ball. At zero spin, the drag coefficient on the grooved ball shows a rapid fall-off at a critical Reynolds number and maintains a minimum value which is lower by 50% than that on smooth ball. At non-zero α, the drag coefficient on the grooved ball increases with increasing α, but is still lower by 40% than that on smooth ball. The lift coefficient on the grooved ball increases with increasing α, and is 100% larger than that on smooth ball. The aerodynamic characteristics of grooved ball is in general quite similar to that of dimpled ball. Some more details will be discussed in the presentation.

  9. Visual Servoing Tracking Control of a Ball and Plate System: Design, Implementation and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Ming-Tzu Ho

    2013-07-01

    Full Text Available This paper presents the design, implementation and validation of real‐time visual servoing tracking control for a ball and plate system. The position of the ball is measured with a machine vision system. The image processing algorithms of the machine vision system are pipelined and implemented on a field programmable gate array (FPGA device to meet real‐ time constraints. A detailed dynamic model of the system is derived for the simulation study.By neglecting the high‐order coupling terms, the ball and plate system model is simplified into two decoupled ball and beam systems, and an approximate input‐ output feedback linearization approach is then used to design the controller for trajectory tracking. The designed control law is implemented on a digital signal processor (DSP. The validity of the performance of the developed control system is investigated through simulation and experimental studies. Experimental results show that the designed system functions well with reasonable agreement with simulations.

  10. Grid Security

    CERN Document Server

    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.

  11. Ceramic Rail-Race Ball Bearings

    Science.gov (United States)

    Balzer, Mark A.; Mungas, Greg S.; Peters, Gregory H.

    2010-01-01

    Non-lubricated ball bearings featuring rail races have been proposed for use in mechanisms that are required to function in the presence of mineral dust particles in very low-pressure, dry environments with extended life. Like a conventional ball bearing, the proposed bearing would include an inner and an outer ring separated by balls in rolling contact with the races. However, unlike a conventional ball bearing, the balls would not roll in semi-circular or gothic arch race grooves in the rings: instead, the races would be shaped to form two or more rails (see figure). During operation, the motion of the balls would push dust particles into the spaces between the rails where the particles could not generate rolling resistance for the balls

  12. Exact Wavelets on the Ball

    CERN Document Server

    Leistedt, B

    2012-01-01

    We develop an exact wavelet transform on the three-dimensional ball (i.e. on the solid sphere), which we name the flaglet transform. For this purpose we first construct an exact harmonic transform on the radial line using damped Laguerre polynomials and develop a corresponding quadrature rule. Combined with the spherical harmonic transform, this approach leads to a sampling theorem on the ball and a novel three-dimensional decomposition which we call the Fourier-Laguerre transform. We relate this new transform to the well-known Fourier-Bessel decomposition and show that band-limitness in the Fourier-Laguerre basis is a sufficient condition to compute the Fourier-Bessel decomposition exactly. We then construct the flaglet transform on the ball through a harmonic tiling, which is exact thanks to the exactness of the Fourier-Laguerre transform (from which the name flaglets is coined). The corresponding wavelet kernels have compact localisation properties in real and harmonic space and their angular aperture is i...

  13. Studies On Falling Ball Viscometry

    CERN Document Server

    Singh, Amit Vikram; Gupta-Bhaya, Pinaki

    2012-01-01

    A new method of accurate calculation of the coefficient of viscosity of a test liquid from experimentally measured terminal velocity of a ball falling in the test liquid contained in a narrow tube is described. The calculation requires the value of a multiplicative correction factor to the apparent coefficient of viscosity calculated by substitution of terminal velocity of the falling ball in Stokes formula. This correction factor, the so-called viscosity ratio, a measure of deviation from Stokes limit, arises from non-vanishing values of the Reynolds number and the ball/tube radius ratio. The method, valid over a very wide range of Reynolds number, is based on the recognition of a relationship between two measures of wall effect, the more widely investigated velocity ratio, defined as the ratio of terminal velocity in a confined medium to that in a boundless medium and viscosity ratio. The calculation uses two recently published correlation formulae based on extensive experimental results on terminal velocit...

  14. Effects of Bonding Wires and Epoxy Molding Compound on Gold and Copper Ball Bonds Intermetallic Growth Kinetics in Electronic Packaging

    Science.gov (United States)

    Gan, C. L.; Classe, F. C.; Chan, B. L.; Hashim, U.

    2014-04-01

    This paper discusses the influence of bonding wires and epoxy mold compounds (EMC) on intermetallic compound (IMC) diffusion kinetics and apparent activation energies ( E aa) of CuAl and AuAl IMCs in a fineline ball grid array package. The objective of this study is to study the CuAl and AuAl IMC growth rates with different epoxy mold compounds and to determine the apparent activation energies of different combination of package bills of materials. IMC thickness measurement has been carried out to estimate the coefficient of diffusion ( D o) and E aa various aging conditions of different EMCs and bonding wires. Apparent activation energies ( E aa) of both wire types were investigated after high temperature storage life tests (HTSL) for both molding compounds. Au bonds were identified to have faster IMC formation, compared to slower IMC growth of Cu. The E aa obtained for CuAl IMC diffusion kinetics are 1.08 and 1.04 eV with EMC A and EMC B, respectively. For AuAl IMC diffusion kinetics, the E aa obtained are 1.04 and 0.98 eV, respectively, on EMC A and EMC B. These values are close to previous HTSL studies conducted on Au and Cu ball bonds and are in agreement to the theory of HTSL performance of Au and Cu bonding wires.Overall, EMC B shows slightly lower apparent activation energy ( E aa) valueas in CuAl and AuAl IMCs. This proves that the different types of epoxy mold compounds have some influence on IMC growth rates.

  15. Fluid Mechanics of Cricket and Tennis Balls

    Science.gov (United States)

    Mehta, Rabindra D.

    2009-11-01

    Aerodynamics plays a prominent role in defining the flight of a ball that is struck or thrown through the air in almost all ball sports. The main interest is in the fact that the ball can often deviate from its initial straight path, resulting in a curved, or sometimes an unpredictable, flight path. It is particularly fascinating that that not all the parameters that affect the flight of a ball are always under human influence. Lateral deflection in flight, commonly known as swing, swerve or curve, is well recognized in cricket and tennis. In tennis, the lateral deflection is produced by spinning the ball about an axis perpendicular to the line of flight, which gives rise to what is commonly known as the Magnus effect. It is now well recognized that the aerodynamics of sports balls are strongly dependent on the detailed development and behavior of the boundary layer on the ball's surface. A side force, which makes a ball curve through the air, can also be generated in the absence of the Magnus effect. In one of the cricket deliveries, the ball is released with the seam angled, which trips the laminar boundary layer into a turbulent state on that side. The turbulent boundary layer separates relatively late compared to the laminar layer on the other side, thereby creating a pressure difference and hence side force. The fluid mechanics of a cricket ball become very interesting at the higher Reynolds numbers and this will be discussed in detail. Of all the round sports balls, a tennis ball has the highest drag coefficient. This will be explained in terms of the contribution of the ``fuzz" drag and how that changes with Reynolds number and ball surface wear. It is particularly fascinating that, purely through historical accidents, small disturbances on the ball surface, such as the stitching on cricket balls and the felt cover on tennis balls are all about the right size to affect boundary layer transition and development in the Reynolds numbers of interest. The fluid

  16. Adiabatic Invariance of Oscillons/I-balls

    CERN Document Server

    Kawasaki, Masahiro; Takeda, Naoyuki

    2015-01-01

    Real scalar fields are known to fragment into spatially localized and long-lived solitons called oscillons or $I$-balls. We prove the adiabatic invariance of the oscillons/$I$-balls for a potential that allows periodic motion even in the presence of non-negligible spatial gradient energy. We show that such potential is uniquely determined to be the quadratic one with a logarithmic correction, for which the oscillons/$I$-balls are absolutely stable. For slightly different forms of the scalar potential dominated by the quadratic one, the oscillons/$I$-balls are only quasi-stable, because the adiabatic charge is only approximately conserved. We check the conservation of the adiabatic charge of the $I$-balls in numerical simulation by slowly varying the coefficient of logarithmic corrections. This unambiguously shows that the longevity of oscillons/$I$-balls is due to the adiabatic invariance.

  17. Structural dynamic analysis of a ball joint

    Science.gov (United States)

    Hwang, Seok-Cheol; Lee, Kwon-Hee

    2012-11-01

    Ball joint is a rotating and swiveling element that is typically installed at the interface between two parts. In an automobile, the ball joint is the component that connects the control arms to the steering knuckle. The ball joint can also be installed in linkage systems for motion control applications. This paper describes the simulation strategy for a ball joint analysis, considering manufacturing process. Its manufacturing process can be divided into plugging and spinning. Then, the interested responses is selected as the stress distribution generated between its ball and bearing. In this paper, a commercial code of NX DAFUL using an implicit integration method is introduced to calculate the response. In addition, the gap analysis is performed to investigate the fitness, focusing on the response of the displacement of a ball stud. Also, the optimum design is suggested through case studies.

  18. From Schwinger Balls to Curved Space

    CERN Document Server

    Allahbakhshi, Davood

    2016-01-01

    It is shown that the Reissner-Nordstrom black hole is also a gravitational Schwinger ball. It is also shown that both massless and massive-particle gravitational Schwinger balls are thermodynamic systems by deriving the first law of thermodynamics for them. Inconsistency between classical geometrical and microscopic definitions of the horizon is discussed. We propose a new metric, more consistent with microscopic picture of black hole, as gravitational Schwinger ball, by speculations. It has some interesting features.

  19. Multifractal properties of ball milling dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Budroni, M. A., E-mail: mabudroni@uniss.it; Pilosu, V.; Rustici, M. [Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, Sassari 07100 (Italy); Delogu, F. [Dipartimento di Ingegneria Meccanica, Chimica, e dei Materiali, Università degli Studi di Cagliari, via Marengo 2, Cagliari 09123 (Italy)

    2014-06-15

    This work focuses on the dynamics of a ball inside the reactor of a ball mill. We show that the distribution of collisions at the reactor walls exhibits multifractal properties in a wide region of the parameter space defining the geometrical characteristics of the reactor and the collision elasticity. This feature points to the presence of restricted self-organized zones of the reactor walls where the ball preferentially collides and the mechanical energy is mainly dissipated.

  20. Grid reliability

    Science.gov (United States)

    Saiz, P.; Andreeva, J.; Cirstoiu, C.; Gaidioz, B.; Herrala, J.; Maguire, E. J.; Maier, G.; Rocha, R.

    2008-07-01

    Thanks to the Grid, users have access to computing resources distributed all over the world. The Grid hides the complexity and the differences of its heterogeneous components. In such a distributed system, it is clearly very important that errors are detected as soon as possible, and that the procedure to solve them is well established. We focused on two of its main elements: the workload and the data management systems. We developed an application to investigate the efficiency of the different centres. Furthermore, our system can be used to categorize the most common error messages, and control their time evolution.

  1. Coefficient of Restitution of Wet Tennis Balls

    OpenAIRE

    Eugene Jang; Tony Kim

    2014-01-01

    The coefficient of restitution of a damp tennis ball is of interest to tennis players. Using a spray bottle, water was added to a tennis ball and the mass of water on the wet ball was determined. The ball was then dropped from a fixed height of 0.86 m. The motion was recorded with a video camera and the bounce height was measured. Using the bounce height and the original height, the coefficient of restitution for that mass of added water was determined. The research found the mass of wa...

  2. Ball Bearing Stacking Automation System

    Directory of Open Access Journals (Sweden)

    Shafeequerrahman S . Ahmed

    2013-01-01

    Full Text Available This document is an effort to introduce the concept of automation in small scale industries and or small workshops that are involved in the manufacturing of small objects such as nuts, bolts and ball bearing in this case. This an electromechanical system which includes certain mechanical parts that involves one base stand on which one vertical metallic frame is mounted and hinged to this vertical stand is an in humanized effort seems inadequate in this era making necessary the use of Electronics, Computer in the manufacturing processes leading to the concept of Automated Manufacturing System (AMS.The ball bearing stack automation is an effort in this regard. In our project we go for stack automation for any object for example a ball bearing, be that is still a manual system there. It will be microcontroller based project control system equipped with microcontroller 89C51 from any manufacturer like Atmel or Philips. This could have been easily implemented if a PLC could be used for manufacturing the staking unit but I adopted the microcontroller based system so that some more modification in the system can be effected at will as to use the same hardware .Although a very small object i.e. ball bearig or small nut and fixture will be tried to be stacked, the system with more precision and more power handling capacity could be built for various requirements of the industry. For increasing more control capacity, we can use another module of this series. When the bearing is ready, it will be sent for packing. This is sensed by an inductive sensor. The output will be proceeds by PLC and microcontroller card which will be driving the assembly in order to put it into pads or flaps. This project will also count the total number of bearings to be packed and will display it on a LCD for real time reference and a provision is made using a higher level language using hyper terminal of the computer

  3. Left atrial ball valve thrombus

    Directory of Open Access Journals (Sweden)

    R. Balaji

    2013-10-01

    Full Text Available "Ball valve thrombus" which is a spherical free floating clot in left atrium is an often quoted, but uncommonly encountered complication in patients with severe mitral stenosis of rheumatic origin, who are in atrial fibrillation. We describe the case of a 31-year-old lady with rheumatic heart disease, severe mitral stenosis and moderately severe aortic stenosis who had undergone closed mitral valvotomy 13 years ago. The patient presented with an episode of non-exertional syncope and breathlessness on exertion of 6 months duration and was in normal sinus rhythm. Echocardiography facilitated ante-mortem diagnosis and prompt institution of surgery was life saving.

  4. Production of single-walled carbon nanotube grids

    Science.gov (United States)

    Hauge, Robert H; Xu, Ya-Qiong; Pheasant, Sean

    2013-12-03

    A method of forming a nanotube grid includes placing a plurality of catalyst nanoparticles on a grid framework, contacting the catalyst nanoparticles with a gas mixture that includes hydrogen and a carbon source in a reaction chamber, forming an activated gas from the gas mixture, heating the grid framework and activated gas, and controlling a growth time to generate a single-wall carbon nanotube array radially about the grid framework. A filter membrane may be produced by this method.

  5. Coefficient of Restitution of a Tennis Ball

    OpenAIRE

    Andre Roux; Jennifer Dickerson

    2007-01-01

    The coefficient of restitution (COR) of a tennis ball was investigated over a range of impact velocities. It was found that the COR of the ball was lower than ATP regulations specify, and that the COR decreased with increasing impact velocity.

  6. Coefficient of Restitution of a Tennis Ball

    Directory of Open Access Journals (Sweden)

    Andre Roux

    2007-06-01

    Full Text Available The coefficient of restitution (COR of a tennis ball was investigated over a range of impact velocities. It was found that the COR of the ball was lower than ATP regulations specify, and that the COR decreased with increasing impact velocity.

  7. Some Mathematics and Physics of Ball Games.

    Science.gov (United States)

    Hughes, D. E.

    1985-01-01

    Gives examples on the applications of arithmetic, geometry, and some calculus, vector algebra, and mechanics to ball games. Suggestions for further interesting investigations are provided together with references to other articles and books on applications of mathematics and physics to ball games and sports in general. (JN)

  8. Delayed Equation for Charged Rigid Nonrelativistic Ball

    CERN Document Server

    Vlasov, A A

    2002-01-01

    Simple expression for self-force acting on radiating rigid charged ball is derived (Sommerfeld ball). It is shown that appropriate delayed equation of motion has solutions in general differ from that for Sommerfeld sphere - there are no "radiationless" solutions, but there are oscillating without damping solutions though self-force has nonzero value.

  9. HIRENASD NLR grid

    Data.gov (United States)

    National Aeronautics and Space Administration — Structured multiblock grid of HIRENASD wing with medium grid density, about 10 mill grid points, 9.5 mill cells. Starting from coarse AIAA AEPW structured grid,...

  10. Development of a low-cost integrated 20-kW ac solar tracking sub- array for grid-connected PV power system applications. Phase 1, Annual technical report, 11 July 1995--31 July 1996

    Energy Technology Data Exchange (ETDEWEB)

    Stern, M.; West, R.; Fourer, G.; Whalen, W.; Van Loo, M.; Duran, G. [Utility Power Group, Chatsworth, CA (United States)

    1997-06-01

    The overall goal of this effort is to reduce the installed cost of utility scale grid connected photovoltaic power systems. The focus of the effort is on ``BOS`` (Balance-Of-System) component manufacturing technology, which essentially involves all PV power system engineering, manufacturing, assembly and construction tasks from the receipt of a PV module to the deliver of grid connected electricity.

  11. Grid reliability

    CERN Document Server

    Saiz, P; Rocha, R; Andreeva, J

    2007-01-01

    We are offering a system to track the efficiency of different components of the GRID. We can study the performance of both the WMS and the data transfers At the moment, we have set different parts of the system for ALICE, ATLAS, CMS and LHCb. None of the components that we have developed are VO specific, therefore it would be very easy to deploy them for any other VO. Our main goal is basically to improve the reliability of the GRID. The main idea is to discover as soon as possible the different problems that have happened, and inform the responsible. Since we study the jobs and transfers issued by real users, we see the same problems that users see. As a matter of fact, we see even more problems than the end user does, since we are also interested in following up the errors that GRID components can overcome by themselves (like for instance, in case of a job failure, resubmitting the job to a different site). This kind of information is very useful to site and VO administrators. They can find out the efficien...

  12. A model for ball lightning

    International Nuclear Information System (INIS)

    A model for ball lightning (BL) is described. It is based upon the vorton model for elementary particles, which exploits the symmetry between electricity and magnetism. The core, or driving engine, of BL in this model is comprised of a vorton-antivorton plasma. The energy of BL, which derives from nucleon decay catalyzed by this plasma, leads, through various mechanisms, to BL luminosity as well as to other BL features. It is argued that this model could also be a suitable explanation for other luminous phenomena, such as the unidentified atmospheric light phenomena seen at Hessdalen. It is predicted that BL and similar atmospheric luminous phenomena should manifest certain features unique to this model, which would be observable with suitable instrumentation

  13. La balle et la plume

    Directory of Open Access Journals (Sweden)

    Peter Marquis

    2012-06-01

    Full Text Available Fin octobre 2008, la nouvelle fit l’effet d’une bombe : Barack Obama, alors candidat à la présidence américaine, demanda à la chaîne câblée Fox News de retarder le début du sixième match de la World Series de base-ball afin de diffuser un spot de campagne. Son adversaire, John McCain, soutenu par le camp républicain et une partie de la population, monta aussitôt au créneau pour dénoncer l’hérésie : s’arroger le droit de perturber cette grande finale du championnat au déroulement immuable reve...

  14. Viscoelastic modelling of tennis ball properties

    Science.gov (United States)

    Sissler, L.; Jones, R.; Leaney, P. G.; Harland, A.

    2010-06-01

    An explicit finite element (FE) tennis ball model which illustrates the effects of the viscoelastic materials of a tennis ball on ball deformation and bounce during normal impacts is presented. A tennis ball is composed of a rubber core and a fabric cover comprised of a wool-nylon mix which exhibit non-linear strain rate properties during high velocity impacts. The rubber core model was developed and validated using low strain rate tensile tests on rubber samples as well as high velocity normal impacts of pressurised cores at velocities ranging from 15 m/s to 50 m/s. The impacts were recorded using a high speed video (HSV) camera to determine deformation, impact time and coefficient of restitution (COR). The material properties of the core model were tuned to match the HSV results. A two component anisotropic fabric model was created which included artificial Rayleigh damping to account for hysteresis effects, and the core model 'tuning' process was used to refine the cloth layer. The ball model's parameters were in good agreement with experimental data at all velocities for both cores and complete balls, and a time sequenced comparison of HSV ball motion and FE model confirmed the validity of the model.

  15. Gravitational Waves from Q-ball Formation

    CERN Document Server

    Chiba, Takeshi; Yamaguchi, Masahide

    2009-01-01

    We study the detectability of the gravitational waves (GWs) from the Q-ball formation associated with the Affleck-Dine (AD) mechanism, taking into account both of the dilution effect due to Q-ball domination and of finite temperature effects. The AD mechanism predicts the formation of non-topological solitons, Q-balls, from which GWs are generated. Q-balls with large conserved charge $Q$ can produce a large amount of GWs. On the other hand, the decay rate of such Q-balls is so small that they may dominate the energy density of the universe, which implies that GWs are significantly diluted and that their frequencies are redshifted during Q-ball dominated era. Thus, the detectability of the GWs associated with the formation of Q-balls is determined by these two competing effects. We find that there is a finite but small parameter region where such GWs may be detected by future detectors such as DECIGO or BBO, only in the case when the thermal logarithmic potential dominates the potential of the AD field. Otherw...

  16. BALL - biochemical algorithms library 1.3

    Directory of Open Access Journals (Sweden)

    Stöckel Daniel

    2010-10-01

    Full Text Available Abstract Background The Biochemical Algorithms Library (BALL is a comprehensive rapid application development framework for structural bioinformatics. It provides an extensive C++ class library of data structures and algorithms for molecular modeling and structural bioinformatics. Using BALL as a programming toolbox does not only allow to greatly reduce application development times but also helps in ensuring stability and correctness by avoiding the error-prone reimplementation of complex algorithms and replacing them with calls into the library that has been well-tested by a large number of developers. In the ten years since its original publication, BALL has seen a substantial increase in functionality and numerous other improvements. Results Here, we discuss BALL's current functionality and highlight the key additions and improvements: support for additional file formats, molecular edit-functionality, new molecular mechanics force fields, novel energy minimization techniques, docking algorithms, and support for cheminformatics. Conclusions BALL is available for all major operating systems, including Linux, Windows, and MacOS X. It is available free of charge under the Lesser GNU Public License (LPGL. Parts of the code are distributed under the GNU Public License (GPL. BALL is available as source code and binary packages from the project web site at http://www.ball-project.org. Recently, it has been accepted into the debian project; integration into further distributions is currently pursued.

  17. Petrography and microanalysis of Pennsylvanian coal-ball concretions (Herrin Coal, Illinois Basin, USA): Bearing on fossil plant preservation and coal-ball origins

    Science.gov (United States)

    Siewers, Fredrick D.; Phillips, Tom L.

    2015-11-01

    Petrographic analyses of 25 coal balls from well-studied paleobotanical profiles in the Middle Pennsylvanian Herrin Coal (Westphalian D, Illinois Basin) and five select coal balls from university collections, indicate that Herrin Coal-ball peats were permineralized by fibrous and non-fibrous carbonates. Fibrous carbonates occur in fan-like to spherulitic arrays in many intracellular (within tissue) pores, and are best developed in relatively open extracellular (between plant) pore spaces. Acid etched fibrous carbonates appear white under reflected light and possess a microcrystalline texture attributable to abundant microdolomite. Scanning electron microscopy, X-ray diffraction, and electron microprobe analysis demonstrate that individual fibers have a distinct trigonal prism morphology and are notable for their magnesium content (≈ 9-15 mol% MgCO3). Non-fibrous carbonates fill intercrystalline spaces among fibers and pores within the peat as primary precipitates and neomorphic replacements. In the immediate vicinity of plant cell walls, non-fibrous carbonates cut across fibrous carbonates as a secondary, neomorphic phase attributed to coalification of plant cell walls. Dolomite occurs as diagenetic microdolomite associated with the fibrous carbonate phase, as sparite replacements, and as void-filling cement. Maximum dolomite (50-59 wt.%) is in the top-of-seam coal-ball zone at the Sahara Mine, which is overlain by the marine Anna Shale. Coal-ball formation in the Herrin Coal began with the precipitation of fibrous high magnesium calcite. The trigonal prism morphology of the carbonate fibers suggests rapid precipitation from super-saturated, meteoric pore waters. Carbonate precipitation from marine waters is discounted on the basis of stratigraphic, paleobotanical, and stable isotopic evidence. Most non-fibrous carbonate is attributable to later diagenetic events, including void-fill replacements, recrystallization, and post-depositional fracture fills. Evidence

  18. Craniofacial reconstruction using rational cubic ball curves.

    Directory of Open Access Journals (Sweden)

    Abdul Majeed

    Full Text Available This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI has also been developed for practical application.

  19. Cohesion in ball lightning and cook plasmas

    International Nuclear Information System (INIS)

    The phenomenon of ball lightning has been observed for a long time, but the nature of these luminous balls has been unknown. It is proposed here that they consist of highly excited Rydberg atoms with large polarizabilities. Thus the cohesion of the balls comes from photon exchange forces (London dispersion forces) rather than electron exchange (chemical) forces. The cohesion in plasmas generated at the back faces of detonating explosives (Cook's plasmas) may have a similar basis. Numerical estimates are given to justify these interpretations

  20. Rotating Boson Stars and Q-Balls

    CERN Document Server

    Kleihaus, B; List, M; Kleihaus, Burkhard; Kunz, Jutta; List, Meike

    2005-01-01

    We consider axially symmetric, rotating boson stars. Their flat space limits represent spinning Q-balls. We discuss their properties and determine their domain of existence. Q-balls and boson stars are stationary solutions and exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the boson stars. We address the flat space limit and the limit of strong gravitational coupling. For comparison we also determine the properties of spherically symmetric Q-balls and boson stars.

  1. Modeling the Rate-Dependent Durability of Reduced-Ag SAC Interconnects for Area Array Packages Under Torsion Loads

    Science.gov (United States)

    Srinivas, Vikram; Menon, Sandeep; Osterman, Michael; Pecht, Michael G.

    2013-08-01

    Solder durability models frequently focus on the applied strain range; however, the rate of applied loading, or strain rate, is also important. In this study, an approach to incorporate strain rate dependency into durability estimation for solder interconnects is examined. Failure data were collected for SAC105 solder ball grid arrays assembled with SAC305 solder that were subjected to displacement-controlled torsion loads. Strain-rate-dependent (Johnson-Cook model) and strain-rate-independent elastic-plastic properties were used to model the solders in finite-element simulation. Test data were then used to extract damage model constants for the reduced-Ag SAC solder. A generalized Coffin-Manson damage model was used to estimate the durability. The mechanical fatigue durability curve for reduced-silver SAC solder was generated and compared with durability curves for SAC305 and Sn-Pb from the literature.

  2. Static Load Distribution in Ball Bearings

    Science.gov (United States)

    Ricci, Mario

    2010-01-01

    A numerical procedure for computing the internal loading distribution in statically loaded, single-row, angular-contact ball bearings when subjected to a known combined radial and thrust load is presented. The combined radial and thrust load must be applied in order to avoid tilting between inner and outer rings. The numerical procedure requires the iterative solution of Z + 2 simultaneous nonlinear equations - where Z is the number of the balls - to yield an exact solution for axial and radial deflections, and contact angles. Numerical results for a 218 angular-contact ball bearing have been compared with those from the literature and show significant differences in the magnitudes of the ball loads, contact angles, and the extent of the loading zone.

  3. Laryngeal Fracture Caused by a Lacrosse Ball.

    Science.gov (United States)

    Trinidade, Aaron; Shakeel, Muhammad; Stickle, Brian; Ah-See, Kim W

    2015-11-01

    Neck injuries in lacrosse are rare and mostly involve the musculoskeletal system. The lacrosse ball is a solid rubber ball of approximately 20 cm in diameter and the fastest shot recorded in professional lacrosse is over 100 mph. Despite wearing full protection, the neck remains prone to blunt trauma by this ball. A 23-year man sustained a direct blow to his left neck by a lacrosse ball during play, resulting in immediate aphonia and stridor. CT scan confirmed a left thyroid lamina fracture. The patient was treated conservatively and his airway was monitored for 24 hours. He made a full recovery. It is important that lacrosse players should be aware of this potential injury and appropriate precautions should be taken to avoid this trauma. PMID:26577976

  4. Hyperbolic monotonicity in the Hilbert ball

    Directory of Open Access Journals (Sweden)

    Reich Simeon

    2006-01-01

    Full Text Available We first characterize -monotone mappings on the Hilbert ball by using their resolvents and then study the asymptotic behavior of compositions and convex combinations of these resolvents.

  5. Staging quantum cryptography with chocolate balls

    OpenAIRE

    Svozil, Karl

    2005-01-01

    Moderated by a director, laymen and students are encouraged to assume the role of quanta and enact a quantum cryptographic protocol. The performance is based on a generalized urn model capable of reproducing complementarity even for classical chocolate balls.

  6. Staging quantum cryptography with chocolate balls

    CERN Document Server

    Svozil, K

    2006-01-01

    Moderated by a director, laymen and students are encouraged to assume the role of quanta and enact a quantum cryptographic protocol. The performance is based on a generalized urn model capable of reproducing complementarity even for classical chocolate balls.

  7. Dolphin underwater bait-balling behaviors in relation to group and prey ball sizes.

    Science.gov (United States)

    Vaughn-Hirshorn, Robin L; Muzi, Elisa; Richardson, Jessica L; Fox, Gabriella J; Hansen, Lauren N; Salley, Alyce M; Dudzinski, Kathleen M; Würsig, Bernd

    2013-09-01

    We characterized dusky dolphin (Lagenorhynchus obscurus) feeding behaviors recorded on underwater video, and related behaviors to variation in prey ball sizes, dolphin group sizes, and study site (Argentina versus New Zealand, NZ). Herding behaviors most often involved dolphins swimming around the side or under prey balls, but dolphins in Argentina more often swam under prey balls (48% of passes) than did dolphins in NZ (34% of passes). This result may have been due to differences in group sizes between sites, since groups are larger in Argentina. Additionally, in NZ, group size was positively correlated with proportion of passes that occurred under prey balls (pdolphins in Argentina more often swam through prey balls (8% of attempts) than did dolphins in NZ (4% of attempts). This result may have been due to differences in prey ball sizes between sites, since dolphins fed on larger prey balls in Argentina (>74m(2)) than in NZ (maximum 33m(2)). Additionally, in NZ, dolphins were more likely to swim through prey balls to capture fish when they fed on larger prey balls (p=0.025).

  8. Smart grids infrastructure, technology, and solutions

    CERN Document Server

    Borlase, Stuart

    2012-01-01

    What exactly is smart grid? Why is it receiving so much attention? What are utilities, vendors, and regulators doing about it? Answering these questions and more, Smart Grids: Infrastructure, Technology, and Solutions gives readers a clearer understanding of the drivers and infrastructure of one of the most talked-about topics in the electric utility market-smart grid. This book brings together the knowledge and views of a vast array of experts and leaders in their respective fields.Key Features Describes the impetus for change in the electric utility industry Discusses the business drivers, b

  9. Heated-Pressure-Ball Monopropellant Rocket Engine

    Science.gov (United States)

    Greene, William D.

    2005-01-01

    A recent technology disclosure presents a concept for a monopropellant thermal spacecraft thruster that would feature both the simplicity of a typical prior pressure-fed propellant supply system and the smaller mass and relative compactness of a typical prior pump-fed system. The source of heat for this thruster would likely be a nuclear- fission reactor. The propellant would be a cryogenic fluid (a liquefied low-molecular-weight gas) stored in a tank at a low pressure. The propellant would flow from the tank, through a feedline, into three thick-walled spherical tanks, denoted pressure balls, that would be thermally connected to the reactor. Valves upstream and downstream of the pressure balls would be operated in a three-phase cycle in which propellant would flow into one pressure ball while the fluid underwent pressurization through heating in another ball and pressurized propellant was discharged from the remaining ball into the reactor. After flowing through the reactor, wherein it would be further heated, the propellant would be discharged through an exhaust nozzle to generate thrust. A fraction of the pressurized gas from the pressure balls would be diverted to maintain the desired pressure in the tank.

  10. The MammoGrid Project Grids Architecture

    CERN Document Server

    McClatchey, R; Manset, D; Hauer, T; Estrella, F; Saiz, P; Rogulin, D; 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...

  11. Secret of a ball lightning

    OpenAIRE

    E.V. Savich

    2013-01-01

    Шаровая молния – явление природы, происходящее при ударе линейной молнии с ее воздействием тепловой и магнитной энергии, возникающей вокруг канала линейной молнии и в результате образующей из окружающего воздуха облако пара, переходящего под воздействием магнитного поля сегнетоэлектрическое состояние. A ball lightning is a natural phenomenon that occurs at a streak lightning stroke with its action by thermal and magnetic energy releasing around the streak lightning channel and transforming...

  12. Introduction to grid computing

    CERN Document Server

    Magoules, Frederic; Tan, Kiat-An; Kumar, Abhinit

    2009-01-01

    A Thorough Overview of the Next Generation in ComputingPoised to follow in the footsteps of the Internet, grid computing is on the verge of becoming more robust and accessible to the public in the near future. Focusing on this novel, yet already powerful, technology, Introduction to Grid Computing explores state-of-the-art grid projects, core grid technologies, and applications of the grid.After comparing the grid with other distributed systems, the book covers two important aspects of a grid system: scheduling of jobs and resource discovery and monitoring in grid. It then discusses existing a

  13. Data Grid Management Systems

    Science.gov (United States)

    Moore, Reagan W.; Jagatheesan, Arun; Rajasekar, Arcot; Wan, Michael; Schroeder, Wayne

    2004-01-01

    The "Grid" is an emerging infrastructure for coordinating access across autonomous organizations to distributed, heterogeneous computation and data resources. Data grids are being built around the world as the next generation data handling systems for sharing, publishing, and preserving data residing on storage systems located in multiple administrative domains. A data grid provides logical namespaces for users, digital entities and storage resources to create persistent identifiers for controlling access, enabling discovery, and managing wide area latencies. This paper introduces data grids and describes data grid use cases. The relevance of data grids to digital libraries and persistent archives is demonstrated, and research issues in data grids and grid dataflow management systems are discussed.

  14. Effect of a ball skill intervention on children's ball skills and cognitive functions

    NARCIS (Netherlands)

    Westendorp-Haverdings, Marieke; Houwen, Suzanne; Hartman, Esther; Mombarg, Remo; Smith, Joanne; Visscher, Chris

    2014-01-01

    Purpose: This study examined the effect of a 16-wk ball skill intervention on the ball skills, executive functioning (in terms of problem solving and cognitive flexibility), and in how far improved executive functioning leads to improved reading and mathematics performance of children with learning

  15. Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

    Science.gov (United States)

    Carboch, Jan; Süss, Vladimir; Kocib, Tomas

    2014-01-01

    Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key points Players have shorter initial move time when they are facing the ball machine. Using the ball machine results in different swing timing and movement coordination. The use of the ball machine should be limited. PMID:24790483

  16. Standard Practice for Determining Resistance of Solar Collector Covers to Hail by Impact With Propelled Ice Balls

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1992-01-01

    1.1 This practice covers a procedure for determining the ability of cover plates for flat-plate solar collectors to withstand impact forces of falling hail. Propelled ice balls are used to simulate falling hailstones. This practice is not intended to apply to photovoltaic cells or arrays. 1.2 This practice defines two types of test specimens, describes methods for mounting specimens, specifies impact locations on each test specimen, provides an equation for determining the velocity of any size ice ball, provides a method for impacting the test specimens with ice balls, and specifies parameters that must be recorded and reported. 1.3 This practice does not establish pass or fail levels. The determination of acceptable or unacceptable levels of ice-ball impact resistance is beyond the scope of this practice. 1.4 The size of ice ball to be used in conducting this test is not specified in this practice. This practice can be used with various sizes of ice balls. 1.5 The categories of solar collector cover plat...

  17. Flight trajectory of a rotating golf ball with grooves

    Science.gov (United States)

    Baek, Moonheum; Kim, Jooha; Choi, Haecheon

    2014-11-01

    Dimples are known to reduce drag on a sphere by the amount of 50% as compared to a smooth surface. Despite the advantage of reducing drag, dimples deteriorate the putting accuracy owing to their sharp edges. To minimize this putting error but maintain the same flight distance, we have devised a grooved golf ball (called G ball hereafter) for several years. In this study, we modify the shape and pattern of grooves, and investigate the flow characteristics of the G ball by performing wind-tunnel experiments at the Reynolds numbers of 0 . 5 ×105 - 2 . 5 ×105 and the spin ratios (ratio of surface velocity to the free-stream velocity) of 0 - 0.6 that include the real golf-ball velocity and rotational speed. We measure the drag and lift forces on the rotating G ball and compare them with those of a smooth ball and two well-known dimpled balls. The lift-to-drag ratio of the G ball is much higher than that of a smooth ball and is in between those of the two dimpled balls. The trajectories of flying golf balls are computed. The flight distance of G ball is almost the same as that of one dimpled ball but slightly shorter than that of the other dimpled ball. The fluid-dynamic aspects of these differences will be discussed at the talk. Supported by 2011-0028032, 2014M3C1B1033980.

  18. Online Variable Topology-Type Photovoltaic Grid-Connected Inverter

    DEFF Research Database (Denmark)

    Wu, Fengjiang; Sun, Bo; Duan, Jiandong;

    2015-01-01

    In photovoltaic (PV) grid-connected generation system, the key focus is how to expand the generation range of the PV array and enhance the total efficiency of the system. This paper originally derived expressions of the total loss and grid current total harmonics distortions of cascaded inverter...

  19. Dark matter balls help supernovae to explode

    Science.gov (United States)

    Froggatt, C. D.; Nielsen, H. B.

    2015-10-01

    As a solution to the well-known problem that the shock wave potentially responsible for the explosion of a supernova actually tends to stall, we propose a new energy source arising from our model for dark matter. Our earlier model proposed that dark matter should consist of cm-large white dwarf-like objects kept together by a skin separating two different sorts of vacua. These dark matter balls or pearls will collect in the middle of any star throughout its lifetime. At some stage during the development of a supernova, the balls will begin to take in neutrons and then other surrounding material. By passing into a ball nucleons fall through a potential of order 10 MeV, causing a severe production of heat — of order 10 foe for a solar mass of material eaten by the balls. The temperature in the iron core will thereby be raised, splitting up the iron into smaller nuclei. This provides a mechanism for reviving the shock wave when it arrives and making the supernova explosion really occur. The onset of the heating due to the dark matter balls would at first stop the collapse of the supernova progenitor. This opens up the possibility of there being two collapses giving two neutrino outbursts, as apparently seen in the supernova SN1987A — one in Mont Blanc and one 4 h 43 min later in both IMB and Kamiokande.

  20. Visualization of flow over a golf ball at Re = 110,000

    CERN Document Server

    Smith, Clinton; Balaras, Elias; Squires, Kyle; Tsunoda, Masaya

    2008-01-01

    The drag on a golf ball can be reduced by dimpling the surface. There have been few studies, primarily experimental, that provide quantitative information on the details of the drag reduction mechanisms. To illuminate the underlying mechanisms, Direct Numerical Simulation (DNS) is applied to the flow around a golf ball using an immersed boundary method. Computations are performed using up to 500 processors on a range of mesh resolutions from 61 million points to 1.2 billion points. Results are presented from simulations performed at a Reynolds number of Re = $1.1\\times 10^5$ using a grid of 1.2 billion points. This video shows the development of instabilities in the near-surface flow, as well as the delay of complete separation due to the development of local shear layers that lead to local separation and reattachment within individual dimples.

  1. Algorithm on robot soccer pass and shoot a ball

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Introduces of robot soccer's competition software of Harbin Institute of Technology(HIT), the con cept of running range and the method of calculating the running range for both the opponent and our teammates according to the distances Between the ball and robot soccers, and therefore the method of calculating the angle that the robot passes or shoots the ball according to the running ranges of both sides. And gives the examples of passing the ball when the ball's position is in the backcourt and shooting the ball when the ball's position is in the frontcourt.

  2. The bouncing ball through a geometrical series

    Science.gov (United States)

    Flores, Sergio; Alfaro, Luis L.; Chavez, Juan E.; Bastarrachea, Aztlan; Hurtado, Jazmin

    2008-10-01

    The mathematical representation of the physical situation related to a bouncing ball on the floor is an important understanding difficulty for most of the students during the introductory mechanics and mathematics courses. The research group named Physics and mathematics in context from the University of Ciudad Juarez is concerned about the versatility in the change from a mathematical representation to the own physical context of any problem under a traditional instruction. In this case, the main idea is the association of the physical properties of the bouncing ball situation to the nearest mathematical model based on a geometrical series. The proposal of the cognitive development is based on a geometrical series that shows the time the ball takes to stop. In addition, we show the behavior of the ratio of the consecutive heights during the motion.

  3. Electrostatic charge bounds for ball lightning models

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, Karl D [Department of Technology, Texas State University, San Marcos, TX 78666 (United States)], E-mail: kdstephan@txstate.edu

    2008-03-15

    Several current theories concerning the nature of ball lightning predict a substantial electrostatic charge in order to account for its observed motion and shape (Turner 1998 Phys. Rep. 293 1; Abrahamson and Dinniss 2000 Nature 403 519). Using charged soap bubbles as a physical model for ball lightning, we show that the magnitude of charge predicted by some of these theories is too high to allow for the types of motion commonly observed in natural ball lightning, which includes horizontal motion above the ground and movement near grounded conductors. Experiments show that at charge levels of only 10-15 nC, 3-cm-diameter soap bubbles tend to be attracted by induced charges to the nearest grounded conductor and rupture. We conclude with a scaling rule that can be used to extrapolate these results to larger objects and surroundings.

  4. Relativistic-microwave theory of ball lightning.

    Science.gov (United States)

    Wu, H-C

    2016-06-22

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.

  5. Relativistic-microwave theory of ball lightning.

    Science.gov (United States)

    Wu, H-C

    2016-01-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics. PMID:27328835

  6. From Schwinger Balls to Black Holes

    CERN Document Server

    Allahbakhshi, Davood

    2016-01-01

    We have shown intriguing similarities between Schwinger balls and black holes. By considering black hole as a gravitational Schwinger ball, we have derived the Bekenstein-Hawking entropy and the first law of black hole thermodynamics as a direct result of the inverse area dependence of the gravitational force. It is also shown that the Planck length is nothing but the gravitational Schwinger length. The relation between the mass and the radius of the black hole is derived by considering the black hole as a Schwinger ball of gravitons. We show how the evolution of the entanglement entropy of the black hole, as Page introduced many years ago, can be obtained by including gravitons in the black hole's evaporation process and using a deformed EPR mechanism. Also this deformed EPR mechanism can solve the information paradox. We show how naive simultaneous usage of Page's argument and equivalence principle leads to firewall problem.

  7. Flaglets: Exact Wavelets on the Ball

    CERN Document Server

    Leistedt, Boris

    2013-01-01

    We summarise the construction of exact axisymmetric scale-discretised wavelets on the sphere and on the ball. The wavelet transform on the ball relies on a novel 3D harmonic transform called the Fourier-Laguerre transform which combines the spherical harmonic transform with damped Laguerre polynomials on the radial half-line. The resulting wavelets, called flaglets, extract scale-dependent, spatially localised features in three-dimensions while treating the tangential and radial structures separately. Both the Fourier-Laguerre and the flaglet transforms are theoretically exact thanks to a novel sampling theorem on the ball. Our implementation of these methods is publicly available and achieves floating-point accuracy when applied to band-limited signals.

  8. Merging Grid Technologies

    NARCIS (Netherlands)

    Begeman, K. G.; Belikov, A. N.; Boxhoorn, D. R.; Dijkstra, F.; Valentijn, E. A.; Vriend, W. -J.; Zhao, Z.

    2010-01-01

    This paper reports the integration of the astronomical Grid solution realised in the Astro-WISE information system with the EGEE Grid and the porting of Astro-WISE applications on EGEE. We review the architecture of the Astro-WISE Grid, define the problems for the integration of the Grid infrastruct

  9. Modeling of PV array characteristic and application in testing system of PV grid-connected inverter%光伏阵列特性仿真及其在光伏并网逆变器测试系统中的应用

    Institute of Scientific and Technical Information of China (English)

    王晓雷; 王卫星; 路进升; 王国军; 周笑

    2011-01-01

    An engineering calculation method for PV (photovoltaic army) array characteristic is proposed, which can calculate the output characteristics of the PV array using the technical parameter ofphotovoltaic cell, total series-units and parallel-branch number of photovoltaic array, and local intensity and temperature. Model ofphotovoltaic array based on MATLAB/simulink is established, and the characteristic curve of the PV array is analysed in detail. Based on the proposed algorithm, the construction and features of the testing system of the first set of PV grid-connected inverter (developed by XJ Group Corporation and Yunnan Power Grid Corporation) are presented. Then some parameters of the inverter (AURORA-PVI-5000-OUTD) are tested by this method. The test results dovetails with original data aimostly, which verifies the correctness and practicability of this method.%提出了一种光伏阵列特性的工程计算方法,基于光伏电池组件的基本技术参数、光伏阵列总的串联单元数和并联支路数、以及现场光照强度和温度,即可得出光伏阵列的特性.以Matlab/Simulink为工具建立仿真模型,详细分析了光伏阵列的特性曲线.以该计算方法为理论基础,介绍了国内第一套光伏并网逆变器测试系统的构成及特点.以此为平台,对型号为AURORA-PVI-5000-OUTD逆变器性能进行了测试,并给出部分测试结果,与该逆变器出厂检测参数基本吻合,验证了该方法的正确性和实用性.

  10. Q-balls in Underground Experiments

    CERN Document Server

    Ouchrif, M

    2000-01-01

    In this paper we present some features of Q-balls and we discuss theirinteractions with matter, and their energy losses in the Earth, for a largerange of velocities. These calculations are used to compute the fractionalgeometrical acceptance of the MACRO detector. Furthermore a systematic analysisof the energy losses of Q-balls in three types of detectors is investigated.More specifically we have computed the light yield in liquid scintillators, theionization in streamer tubes and the Restricted Energy Loss in the CR39 nucleartrack detectors.

  11. Soccer ball lift coefficients via trajectory analysis

    Energy Technology Data Exchange (ETDEWEB)

    Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: goff@lynchburg.ed [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2010-07-15

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  12. Reasonable Ball Size of Ball Mill for Preparing Coal Water Fuel and Forecasting Productive Capacity

    Institute of Scientific and Technical Information of China (English)

    张荣曾; 刘炯天; 徐志强; 郑明

    2002-01-01

    By using the matrix theory, a 5-parameter grinding mathema tical model is established. Based on the properties of feed coal and requirement s for size distribution of final product, the model gives the required grinding probability for various particles and corresponding ball size distribution. By u sing this model, 3 different sizes of ball mill are designed and put into commer cial use for coal water fuel. The forecasted ball mill capacity, the particle si zes and particle size distribution as well as the coal water fuel quality parame ters are all in line with industrial operation results, which have proved the su itability of the model.

  13. Levitation of an iron ball in midair without active control

    Science.gov (United States)

    Sasaki, S.; Yagi, I.; Murakami, M.

    2004-02-01

    An iron ball floats in midair in a plastic box when several iron balls were attracted by a permanent magnet. A complex interaction between magnetized sphere materials and a lifting magnet enabled the suspension of an iron ball. The balls in the first row are simply attracted by the lifting magnet. The ball in the second row is also attracted by the lifting magnet, however, due to the repulsive forces exerted from the balls sitting above, it can float in midair. We also found that there are two stable positions for the ball to float. The floating ball could be transported from one equilibrium position to another by simply rotating the lifting magnet. This will make it possible to construct a noncontact load transport device.

  14. Receiver architecture of the thousand-element array (THEA)

    NARCIS (Netherlands)

    Kant, G.W.; Kokkeler, A.B.J.; Smolders, A.B.; Gunst, A.W.

    2000-01-01

    As part of the development of a new international radio-telescope SKA (Square Kilometre Array), an outdoor phasedarray prototype, the THousand Element Array (THEA), is being developed at NFRA. THEA is a phased array with 1024 active elements distributed on a regular grid over a surface of approximat

  15. Detecting supersymmetric Q-balls with neutron stars

    OpenAIRE

    Madsen, Jes

    1998-01-01

    Supersymmetric Q-balls trapped in neutron stars or white dwarfs may cause the stars to explode. Trapping of Q-balls in neutron stars is shown to be less likely, but trapping in neutron star progenitors more likely than hitherto assumed, making neutron stars very sensitive Q-ball "detectors". White dwarfs only trap potentially dangerous Q-balls in a narrow parameter range.

  16. Selection of Parameters in Ball-Spinning

    Institute of Scientific and Technical Information of China (English)

    Maosheng LI; Yongnian YAN; Shihong ZHANG; Dachang KANG

    2004-01-01

    Nowadays, with the development of spinning processes, more and more systematic research about spinning parameters has been published. Based on these results, a routing about how to select spinning parameters has been gradually formed. However, ball spinning, due to its own features plus research lack, is still unclear about its parameter selections. In addition, some manufacture-enterprises only notice the use of this technique whereas ignore the theory creation. The optimal parameters about the ball spinning although have been released from these enterprises but in fact not a helpful theory for other researchers and producers. Focus on selecting the parameters based on the trial-and-error, this article has carried a series of experiments to study the influence on the spinning working course from those parameters, especially the peeling phenomena, and the tube diameter bulging. An optimal graph of the working angle, the axial feeding rate, and the acceptable working course is put forward. Additionally, based on the theory of the minimal reduction rate, the selection of the ball diameter is finally described. Thus, it has given the rules to get the proper parameters in ball spinning.

  17. Soccer Ball Production for Nike in Pakistan

    NARCIS (Netherlands)

    K.A. Siegmann (Karin Astrid)

    2008-01-01

    textabstractThis paper looks at how Nike’s soccer ball suppliers (previous and current) in Sialkot (Pakistan) fare in relation to the company’s code of ethics. While minimum required working conditions are implemented, the criteria for social and environmental compliance are not met with. The multin

  18. Introducing a High Bounce Ball Unit

    Science.gov (United States)

    Bernardo, Pat

    2004-01-01

    Those growing up in the 1950s, 60s or 70s are familiar with how physically active children were before computers and video games were introduced. Each neighborhood had its own version of the various games that were played. Many of these games involved a pink rubber ball called a Spaldeen. They were everywhere and almost everyone had one. These…

  19. Fractal Aggregates in Tennis Ball Systems

    Science.gov (United States)

    Sabin, J.; Bandin, M.; Prieto, G.; Sarmiento, F.

    2009-01-01

    We present a new practical exercise to explain the mechanisms of aggregation of some colloids which are otherwise not easy to understand. We have used tennis balls to simulate, in a visual way, the aggregation of colloids under reaction-limited colloid aggregation (RLCA) and diffusion-limited colloid aggregation (DLCA) regimes. We have used the…

  20. Holomorphic Spaces in the Unit Ball of

    Directory of Open Access Journals (Sweden)

    Augusto Guadalupe Miss Paredes

    2013-01-01

    Full Text Available We introduce the and vector spaces of holomorphic functions defined in the unit ball of , generalizing previous work like Ouyang et al. (1998, Stroethoff (1989, and Choa et al. (1992. Likewise, we characterize those spaces in terms of harmonic majorants as a generalization of Arellano et al. (2000.

  1. 4. pi. physics with the plastic ball

    Energy Technology Data Exchange (ETDEWEB)

    Gutbrod, H.H.; Loehner, H.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G.; Warwick, A.; Weik, F.; Wieman, H.

    1982-10-01

    4 ..pi.. data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density.

  2. Dark Matter Balls Help Supernovae to Explode

    CERN Document Server

    Froggatt, Colin D

    2015-01-01

    As a solution to the well-known problem that the shock wave potentially responsible for the explosion of a supernova actually tends to stall, we propose a new energy source arising from our model for dark matter. Our earlier model proposed that dark matter should consist of cm-large white dwarf-like objects kept together by a skin separating two different sorts of vacua. These dark matter balls or pearls will collect in the middle of any star throughout its lifetime. At some stage during the development of a supernova the balls will begin to take in neutrons and then other surrounding material. By passing into a ball nucleons fall through a potential of order 10 MeV, causing a severe production of heat - of order 10 foe for a solar mass of material eaten by the balls. The temperature in the iron core will thereby be raised, splitting up the iron into smaller nuclei. This provides a mechanism for reviving the shock wave when it arrives and making the supernova explosion really occur. The onset of the heating d...

  3. 4 π physics with the plastic ball

    International Nuclear Information System (INIS)

    4 π data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density

  4. A plasma ball in the Microcosm museum

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    Plasma balls, like the one shown here, are displayed in the Microcosm exhibition where families can visit to learn more about the experiments carried out in a research institute like CERN. Hands-on activities allow visitors to get a step closer to the research activities carried out at CERN.

  5. The Ball Aptitude Battery (Test Review).

    Science.gov (United States)

    Hall, Alfred E.

    1985-01-01

    The 12 subtests of the Ball Aptitude Battery (BAB) listed in the administration manual were described. The reviewer believes this aptitude battery, designed for use with high school students and adults in job selection and placement, needs major improvements. It is suggested that the BAB be used solely for research purposes. (DWH)

  6. The dynamic behavior of squash balls

    Science.gov (United States)

    Lewis, Gareth J.; Arnold, J. Cris; Griffiths, Iwan W.

    2011-03-01

    The behavior of a squash ball constitutes an excellent case study of the dynamic behavior of rubbery materials. It is shown that the complex viscoelastic behavior of rubber can be investigated using simple drop bounce tests and compression tests. The drop tests show that the coefficient of restitution increases as the ball temperature increases. The compression tests show that as the speed of compression increases or as the ball temperature decreases, the compressive force and the energy loss both increase. These effects are due to the viscoelastic nature of the rubber and are an excellent example of the time-temperature equivalence of polymers. Compression tests were performed on balls with small holes at the base to separate the effects of the internal air pressure from the material deformation. It was found that the internal air pressure contributed about one-third to the compressive force, but contributed little to energy loss. This behavior shows that the rubber material dominates the rebound behavior and that the normal warming up process at the start of a squash game is important to raise the temperature of the rubber rather than to increase the internal air pressure.

  7. Neutrino Balls and Gamma-Ray Bursts

    CERN Document Server

    Holdom, B

    1994-01-01

    We propose a mechanism by which the neutrino emission from a supernova-type explosion can be converted into a gamma-ray burst of total energy $\\sim 10^{50}$ ergs. This occurs naturally if the explosion is situated inside a ball of trapped neutrinos, which in turn may lie at a galactic core. There are possible unique signatures of this scenario.

  8. 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.

  9. Measuring the Rebound Resilience of a Bouncing Ball

    Science.gov (United States)

    Wadhwa, Ajay

    2012-01-01

    Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property "rebound resilience" and express it as the ratio of the rebound height to…

  10. Frictional torque numbers for ball cup and journal bearings

    NARCIS (Netherlands)

    Ligterink, D.J.

    1982-01-01

    Plastic bearing material wears in ball cup and journal bearings. Contact areas in the ball cup and the journal bearing increase. The frictional torque needed to rotate the ball or journal also increases. When the coefficient of friction is assumed to be constant during wearing out, the frictional t

  11. Frictional torque numbers for ball cup and journal bearings

    OpenAIRE

    Ligterink, D.J.

    1982-01-01

    Plastic bearing material wears in ball cup and journal bearings. Contact areas in the ball cup and the journal bearing increase. The frictional torque needed to rotate the ball or journal also increases. When the coefficient of friction is assumed to be constant during wearing out, the frictional torque increases to a maximum of 1.273 times the frictional torque at zero wear.

  12. Temperature and Coefficient of Restitution of a Table Tennis Ball

    Directory of Open Access Journals (Sweden)

    Yoonyoung Chang

    2016-01-01

    Full Text Available The coefficient of restitution (COR of a bouncing table tennis ball was measured at varying ball temperatures with a Motion Detector. It was found that there is a negative linear relationship between the COR and the temperature of the table tennis ball for temperatures ranging from 5 to 56 ̊C.

  13. 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

  14. Search for strange quark matter and Q-balls with the SLIM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sahnoun, Z., E-mail: sahnoun@bo.infn.i [INFN Sez. Bologna, 40127 Bologna (Italy); Astrophysics Department, CRAAG, BP 63 Bouzareah, 16340 Algiers (Algeria)

    2009-10-15

    We report on the search for Strange Quark Matter (SQM) and charged Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.) from 2001 to 2005. The SLIM experiment was a 427 m{sup 2} array of Nuclear Track Detectors (NTDs) arranged in modules of 24 x 24 cm{sup 2} area. SLIM NTDs were exposed to the cosmic radiation for 4.22 years after which they were brought back to the Bologna Laboratory where they were etched and analyzed. We estimate the properties and energy losses in matter of nuclearites (large SQM nuggets), strangelets (small charged SQM nuggets) and Q-balls; and discuss their detection with the SLIM experiment. The flux upper limits in the CR of such downgoing particles are at the level of 1.3 x 10{sup -15} cm{sup -2} s{sup -1} sr{sup -1} (90% CL).

  15. Search for strange quark matter and Q-balls with the SLIM experiment

    CERN Document Server

    Sahnoun, Z

    2008-01-01

    We report on the search for Strange Quark Matter (SQM) and charged Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.) from 2001 to 2005. The SLIM experiment was a 427 m$^{2}$ array of Nuclear Track Detectors (NTDs) arranged in modules of $24 \\times 24$ cm$^{2}$ area. SLIM NTDs were exposed to the cosmic radiation for 4.22 years after which they were brought back to the Bologna Laboratory where they were etched and analyzed. We estimate the properties and energy losses in matter of nuclearites (large SQM nuggets), strangelets (small charged SQM nuggets) and Q-balls; and discuss their detection with the SLIM experiment. The flux upper limits in the CR of such downgoing particles are at the level of $1.3 10^{-15}$/cm$^{2}$/s/sr (90% CL).

  16. Steel balls forming by cross rolling with upsetting

    Directory of Open Access Journals (Sweden)

    Z. Pater

    2013-01-01

    Full Text Available The paper describes a process of forming four balls with a diameter of 22 mm by means of cross rolling with upsetting. The paper also presents the tool used to form semi-finished balls. Owing to the application of the finite element method (FEM, the course of the rolling process as well as temperature and strain distributions in the obtained balls could be presented. The rolling tests conducted in laboratory conditions at the Lublin University of Technology have proved that the balls produced with the developed rolling method meet the demands for grinding media used in ball mills.

  17. Lawn tennis balls, Rolling friction experiment and Trouton viscosity

    CERN Document Server

    Singh, Ankit; Kulkarni, Kaustubh; Budhraja, Abhishek; Tej, K R Sai; Sankarlingam, Satish; Biswas, Anindya Kumar

    2008-01-01

    Three lawn tennis balls were arbitrarily taken. One ball was new, one was moderately old and another was old. We have fabricated a conveyor belt set-up and measured rolling friction coefficients, $\\mu_{r}$, of the three balls as a function of their angular velocities, $\\omega$. For the new ball, quadratic fit is perfect. For the moderately old ball, linear fit is accurate. In all the three cases, from linear fits, we obtain $k_{rol}$, where, $\\mu_{r}= k_{rol} \\omega + intercept$. We deduce $k_{rol}$ theoretically also, assuming Trouton ratio as three. The experimental results and theoretical estimates are of the same order of magnitude.

  18. RoSiB - a 4π silicon ball for charged-particle detection in EUROBALL

    Science.gov (United States)

    Pausch, G.; Prade, H.; Sobiella, M.; Schnare, H.; Schwengner, R.; Käubler, L.; Borcan, C.; Ortlepp, H.-G.; Oehmichen, U.; Grawe, H.; Schubart, R.; Gerl, J.; Cederkäll, J.; Johnson, A.; Kerek, A.; Klamra, W.; Moszyński, M.; Wolski, D.; Kapusta, M.; Axelsson, A.; Weiszflog, M.; Härtlein, T.; Pansegrau, D.; de Angelis, G.; Ashrafi, S.; Likar, A.; Lipoglavšek, M.

    2000-04-01

    A 4π silicon ball for detection and identification of light charged particles in large multidetector γ-arrays as EUROBALL is presented. The design is based on a N=42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive material for γ-rays is minimized to the detector thickness of 300 or 500 μm and a 0.63 mm ceramic backing. The geometrical coverage is designed for about 90% of 4π. A pulse shape discrimination method with totally depleted detectors working in the reverse mount allows identifying protons and α-particles above an energy threshold of about 2 MeV. The performances of the ball were tested at the tandem - booster accelerator combination of the MPI Heidelberg in two experiments using the high-recoil reaction of 228 MeV 58Ni+ 46Ti and the low-recoil reaction of 95 MeV 16O+ 58Ni . The two-dimensional spectra of zero-crossing (ZC) versus energy confirmed an excellent discrimination of protons and α-particles in all the detectors at different angles. The energy spectra of protons and α-particles measured in the experiments are presented, too. The γ-spectra measured in coincidence with various combinations of emitted particles showed a high selectivity of the ball. The reduced total efficiency for protons of 59% and 55% and α-particles of 44% and 32% measured in a nuclear spectroscopy application is analyzed in a Monte-Carlo simulation (GEANT). It is due to a combined influence of a thick target needed to stop the recoiling residual nuclei and thick absorbers needed to protect the Si-detectors from scattered beam. The results along with the GEANT extrapolation to optimum experimental conditions confirm that RoSiB is a highly efficient and selective device for identification of rare reaction channels with heavy ions.

  19. RSW hexahedral grids

    Data.gov (United States)

    National Aeronautics and Space Administration — RSW hexahedral grids in CGNS (unstructured) and Plot3d (structured) formats generated by ANSYS Germany. Please see AePW_RSW_Grids.pptx below for full description of...

  20. RSW Modified Inflow Grid

    Data.gov (United States)

    National Aeronautics and Space Administration — After discussions by the organizing committee, and some research using the RSW grids, a modification has been made on the RSW grids. The inflow boundary has now...

  1. Business in the Grid

    OpenAIRE

    Schikuta, Erich; Weishaeupl, Thomas; Donno, Flavia; Stockinger, Heinz; Vinek, Elisabeth; Wanek, Helmut; Witzany, Christoph; Haq, Irfan Ul

    2009-01-01

    From 2004 to 2007 the Business In the Grid (BIG) project took place and was driven by the following goals: Firstly, make business aware of Grid technology and, secondly, try to explore new business models. We disseminated Grid computing by mainly concentrating on the central European market and interviewed several companies in order to gain insights into the Grid acceptance in industrial environments. In this article we present the results of the project, elaborate on a critical discussion on...

  2. GRID infrastructure sustainability guidelines

    OpenAIRE

    Ray, Nicolas; Gorgan, Dorian; Giuliani, Gregory

    2010-01-01

    A grid computing infrastructure can be defined as a cluster of loosely coupled, networked computers acting in concert to perform very large tasks. Grid computing is an important part of the enviroGRIDS project, because it will allow one to perform computationally-intensive simulations of the hydrological balance of the Black Sea Catchment and will permit to analyze large quantity of high resolution data sets. It is therefore important that the ability to use grid computing is maintained throu...

  3. The strange flight behaviour of slowly spinning soccer balls.

    Science.gov (United States)

    Mizota, Taketo; Kurogi, Kouhei; Ohya, Yuji; Okajima, Atsushi; Naruo, Takeshi; Kawamura, Yoshiyuki

    2013-01-01

    The strange three-dimensional flight behaviour of slowly spinning soccer balls is one of the most interesting and unknown phenomenon associated with the trajectories of sports balls. Many spectators have experienced numerous exciting and emotional instances while observing the curious flight behaviour of these balls. We examine the aerodynamic mechanisms of erratic ball behaviours through real flight observations, unsteady force measurements and flow pattern visualisations. The strange behaviour is elucidated by the relationship between the unsteady forces on the ball and the wake flow. The irregular changes in position for twin longitudinal vortices have already been discovered in the supercritical Reynolds number region of a sphere with a smooth surface. This finding is applicable to the strange behaviour of the flight of soccer balls with this supercritical flow. The players, spectators, and television viewers will gain greater insight into the effects of soccer ball flights. PMID:23695000

  4. Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

    Directory of Open Access Journals (Sweden)

    Jan Carboch, Vladimir Süss, Tomas Kocib

    2014-06-01

    Full Text Available Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server. Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing.

  5. 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...

  6. 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.

  7. Grid Enabled Remote Instrumentation

    CERN Document Server

    Meyer, Norbert

    2008-01-01

    Focuses on a number of aspects related to the exploitation of remote instrumentation on the grid. This book includes middleware architecture, high speed networking in support of grid applications, wireless grid for acquisition devices and sensor networks, quality of service provisioning for real time control, and measurement instrumentation.

  8. 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...

  9. Perceptual elements in Penn & Teller's "Cups and Balls" magic trick.

    Science.gov (United States)

    Rieiro, Hector; Martinez-Conde, Susana; Macknik, Stephen L

    2013-01-01

    Magic illusions provide the perceptual and cognitive scientist with a toolbox of experimental manipulations and testable hypotheses about the building blocks of conscious experience. Here we studied several sleight-of-hand manipulations in the performance of the classic "Cups and Balls" magic trick (where balls appear and disappear inside upside-down opaque cups). We examined a version inspired by the entertainment duo Penn & Teller, conducted with three opaque and subsequently with three transparent cups. Magician Teller used his right hand to load (i.e. introduce surreptitiously) a small ball inside each of two upside-down cups, one at a time, while using his left hand to remove a different ball from the upside-down bottom of the cup. The sleight at the third cup involved one of six manipulations: (a) standard maneuver, (b) standard maneuver without a third ball, (c) ball placed on the table, (d) ball lifted, (e) ball dropped to the floor, and (f) ball stuck to the cup. Seven subjects watched the videos of the performances while reporting, via button press, whenever balls were removed from the cups/table (button "1") or placed inside the cups/on the table (button "2"). Subjects' perception was more accurate with transparent than with opaque cups. Perceptual performance was worse for the conditions where the ball was placed on the table, or stuck to the cup, than for the standard maneuver. The condition in which the ball was lifted displaced the subjects' gaze position the most, whereas the condition in which there was no ball caused the smallest gaze displacement. Training improved the subjects' perceptual performance. Occlusion of the magician's face did not affect the subjects' perception, suggesting that gaze misdirection does not play a strong role in the Cups and Balls illusion. Our results have implications for how to optimize the performance of this classic magic trick, and for the types of hand and object motion that maximize magic misdirection.

  10. Grid welding fixture for a spacer grid

    International Nuclear Information System (INIS)

    A modular grid welding fixture for a spacer grid that facilitates full grid laser welding of a spacer grid in one setup is disclosed. The modular design allows for partial implementation of each weld type. A base plate is used for mounting to the positioning/rotational plate of the welding system. A removable sub-plate received in the base plate is used to position the grid strips for proper location for welding. A top fixture plate is aligned with the base plate and provides for mounting of a second sub-plate if required. Side plates with spring loaded pressure pads that are hinged to the top fixture plate apply uniform pressure to the outer grid strips during processing. The base plate, top plate, side plate, and pressure pads are provided with a plurality of through holes to allow access of the laser beam for welding. Corner clips are used to insure contact of the overlapping sections of the outer grid strips for proper corner welding. 4 figs

  11. Isoguanine octamer: From bowl to ball

    Science.gov (United States)

    Gu, Jiande; Wang, Jing; Leszczynski, Jerzy

    2007-09-01

    Isoguanine (2-oxo-6-amino-guanine, isoG) can form the higher-order self-pairing ionophore structures by regulating the concentration of metal ions. The metal ion coordinated isoG-tetrads adopt bowl-like shape with the metal ion located at the bottom of the bowl. The present study of the formation of the H-bonded octamers ((isoG 4-M +) 2; M + = Na +, K +) illustrates that the bowl-shaped isoG 4-M + complexes are able to form the extraordinary ball-shaped octamers (isoG 4-M +) 2 H-bonded through the H(N6) and N7 sites. A moderate energy barrier predicted for the process of separating the ball-shaped octamer into two bowl-shaped tetrads and the unique structural features of the octamer suggests a possibility towards construction of the self-assembled isoG nanostructures.

  12. Dust ball physics and the Schwarzschild metric

    CERN Document Server

    Kassner, Klaus

    2016-01-01

    A physics-first derivation of the Schwarzschild metric is given. Gravitation is described in terms of the effects of tidal forces (or of spacetime curvature) on the volume of a small ball of test particles (a dust ball), freely falling after all particles were at rest with respect to each other initially. The possibility to express Einstein's equation this way and some of its ramifications have been enjoyably discussed by Baez and Bunn [Am. J. Phys. 73, 644 (2005)]. Since the formulation avoids the use of tensors, neither advanced tensor calculus nor sophisticated differential geometry are needed in the calculation. The derivation is not lengthy and it has visual appeal, so it may be useful in teaching.

  13. The Neutrino Ball Model of a Quasar

    CERN Document Server

    Manka, R; Karczewska, D

    1993-01-01

    It is suggested that the nonorthodox model of a quasar as a neutrino ball described in terms of the standard model extended by adding right-handed neutrinos and the Majorana scalar field can be presented in order to explain a quasar as a body of weak interacting neutrinos. Neutrino interaction with the scalar Majorana field violates the lepton number and produces the mass splitting of the neutrino due to the sea-saw mechanism. In this model a quasar is an object which appears in the result of the first order cosmological phase transition. In this interpretation a quasar may be regarded as a ball filled with Dirac neutrinos and can be treated as a remnant of phase transition with unbroken global lepton symmetry. In this paper we study the macroscopic parameters of such a configuration. In the result the mass-radius curve M(R) for the quasar is obtained.

  14. Independence, low balling and learning effects

    OpenAIRE

    Simons, Dirk

    2007-01-01

    Independent auditors serve as gatekeepers of public securities markets, but ongoing competition among audit firms could harm auditors’ independence. For instance, a Green Paper of the European Union finds that especially audits of large and prestigious clients are hard-fought in terms of price competition. Major concerns are related to a pricing behavior called low balling. Here, the auditor sets the first period’s fee below the audit costs -incurring a loss for the initial audit- in order to...

  15. Soccer Ball Production for Nike in Pakistan

    OpenAIRE

    Siegmann, Karin Astrid

    2008-01-01

    textabstractThis paper looks at how Nike’s soccer ball suppliers (previous and current) in Sialkot (Pakistan) fare in relation to the company’s code of ethics. While minimum required working conditions are implemented, the criteria for social and environmental compliance are not met with. The multinational’s decision to withdraw orders from the previous supplier ostensibly due to allegations of child labour and unauthorised subcontracting hit large sections of the workforce, especially rural,...

  16. Low-Wear Ball-Bearing Separator

    Science.gov (United States)

    Hawkinson, Elden L.

    1991-01-01

    Proposed ball-bearing separator for use in cryogenic pump stronger and more resistant to wear. Consists of molded plastic-and-metal composite ring imbued with solid lubricant and containing embedded metal ring. Obtains combination of strength and lubricity. Before molding and machining, ring includes tooling portion for handling and indexing. Molded composite blend of PTFE and fluorinated ethylene/propylene (FEP) filled with brass and bronze powder and molybdenum disulfide powder.

  17. Gravitational effects on critical Q-balls

    Science.gov (United States)

    Metaxas, D.

    2007-04-01

    In a cosmological phase transition in theories that admit Q-balls there is a value of the soliton charge above which the soliton becomes unstable and expands, converting space to the true vacuum, much like a critical bubble in the case of ordinary tunneling. Here I consider the effects of gravity on these solitons and I calculate the lowest gravitational corrections to the critical radius and charge.

  18. Gravitational effects on critical Q-balls

    CERN Document Server

    Metaxas, D

    2004-01-01

    In a first-order phase transition in theories that admit Q-balls there is a value of the soliton charge above which the soliton becomes unstable and expands, converting space to the true vacuum, much like a critical bubble in the case of ordinary tunneling. Here I consider the effects of gravity on these solitons and I calculate the lowest gravitational corrections to the critical radius and charge.

  19. 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.

  20. Business in the Grid

    CERN Document Server

    Schikuta, Erich; Donno, Flavia; Stockinger, Heinz; Vinek, Elisabeth; Wanek, Helmut; Witzany, Christoph; Haq, Irfan Ul

    2009-01-01

    From 2004 to 2007 the Business In the Grid (BIG) project took place and was driven by the following goals: Firstly, make business aware of Grid technology and, secondly, try to explore new business models. We disseminated Grid computing by mainly concentrating on the central European market and interviewed several companies in order to gain insights into the Grid acceptance in industrial environments. In this article we present the results of the project, elaborate on a critical discussion on business adaptations, and describe a novel dynamic authorization workflow for business processes in the Grid.

  1. CVD carbon powders modified by ball milling

    Directory of Open Access Journals (Sweden)

    Kazmierczak Tomasz

    2015-09-01

    Full Text Available Carbon powders produced using a plasma assisted chemical vapor deposition (CVD methods are an interesting subject of research. One of the most interesting methods of synthesizing these powders is using radio frequency plasma. This method, originally used in deposition of carbon films containing different sp2/sp3 ratios, also makes possible to produce carbon structures in the form of powder. Results of research related to the mechanical modification of these powders have been presented. The powders were modified using a planetary ball mill with varying parameters, such as milling speed, time, ball/powder mass ratio and additional liquids. Changes in morphology and particle sizes were measured using scanning electron microscopy and dynamic light scattering. Phase composition was analyzed using Raman spectroscopy. The influence of individual parameters on the modification outcome was estimated using statistical method. The research proved that the size of obtained powders is mostly influenced by the milling speed and the amount of balls. Powders tend to form conglomerates sized up to hundreds of micrometers. Additionally, it is possible to obtain nanopowders with the size around 100 nm. Furthermore, application of additional liquid, i.e. water in the process reduces the graphitization of the powder, which takes place during dry milling.

  2. Framework for Grid Manufacturing

    Institute of Scientific and Technical Information of China (English)

    陈笠; 邓宏; 邓倩妮; 吴振宇

    2004-01-01

    With the development of networked manufacturing, it is more and more imminent to solve problems caused by inherent limitations of network technology, such as heterogeneity, collaboration collision, and decentralized control.This paper presents a framework for grid manufacturing, which neatly combines grid technology with the infrastructure of advanced manufacturing technology.The paper studies grid-oriented knowledge description and acquisition, and constructs a distributed knowledge grid model.The paper also deals with the protocol of node description in collaborative design, and describes a distributed collaborative design model.The protocol and node technology leads to a collaborative production model for grid manufacturing.The framework for grid manufacturing offers an effective and feasible solution for the problems of networked manufacturing.The grid manufacturing will become an advanced distributed manufacturing model and promote the development of advanced manufacturing technologies.

  3. Low Sidelobe Sparse Concentric Ring Arrays Optimization Using Modified GA

    Directory of Open Access Journals (Sweden)

    Ke-song Chen

    2015-01-01

    Full Text Available To minimize the peak sidelobe level (PSLL of sparse concentric ring arrays, this paper presents an optimization method of grid ring radii of these arrays. The proposed method is based on modified real genetic algorithm (MGA; it makes grid ring radii as optimal variables and makes elements more reasonably distributed on the array aperture. Also, it can improve the PSLL of the sparse concentric ring arrays and can meanwhile control the computational cost. The simulated results confirming the efficiency and the robustness of the algorithm are provided at last.

  4. A Real-time Modeling of Photovoltaic Array

    Institute of Scientific and Technical Information of China (English)

    王魏; 李柠; 李少远

    2012-01-01

    This paper mainly aims at the modeling problem of the photovoltaic (PV) array with a 30 kW PV grid-connected generation system. An iterative method for the time-varying parameters is proposed to model a plant of PV array. The relationship of PV cell and PV array is obtained and the solution for PV array model is unique. The PV grid-connected generation system is used to demonstrate the effectiveness of the proposed method by comparing the calculated values with the actual output of the system.

  5. Adaptive Mesh Refinement for Characteristic Grids

    CERN Document Server

    Thornburg, Jonathan

    2009-01-01

    I consider techniques for Berger-Oliger adaptive mesh refinement (AMR) when numerically solving partial differential equations with wave-like solutions, using characteristic (double-null) grids. Such AMR algorithms are naturally recursive, and the best-known past Berger-Oliger characteristic AMR algorithm, that of Pretorius & Lehner (J. Comp. Phys. 198 (2004), 10), recurses on individual "diamond" characteristic grid cells. This leads to the use of fine-grained memory management, with individual grid cells kept in 2-dimensional linked lists at each refinement level. This complicates the implementation and adds overhead in both space and time. Here I describe a Berger-Oliger characteristic AMR algorithm which instead recurses on null \\emph{slices}. This algorithm is very similar to the usual Cauchy Berger-Oliger algorithm, and uses relatively coarse-grained memory management, allowing entire null slices to be stored stored in contiguous arrays in memory. The algorithm is very efficient in both space and ti...

  6. Securing smart grid technology

    Science.gov (United States)

    Chaitanya Krishna, E.; Kosaleswara Reddy, T.; Reddy, M. YogaTeja; Reddy G. M., Sreerama; Madhusudhan, E.; AlMuhteb, Sulaiman

    2013-03-01

    In the developing countries electrical energy is very important for its all-round improvement by saving thousands of dollars and investing them in other sector for development. For Growing needs of power existing hierarchical, centrally controlled grid of the 20th Century is not sufficient. To produce and utilize effective power supply for industries or people we should have Smarter Electrical grids that address the challenges of the existing power grid. The Smart grid can be considered as a modern electric power grid infrastructure for enhanced efficiency and reliability through automated control, high-power converters, modern communications infrastructure along with modern IT services, sensing and metering technologies, and modern energy management techniques based on the optimization of demand, energy and network availability and so on. The main objective of this paper is to provide a contemporary look at the current state of the art in smart grid communications as well as critical issues on smart grid technologies primarily in terms of information and communication technology (ICT) issues like security, efficiency to communications layer field. In this paper we propose new model for security in Smart Grid Technology that contains Security Module(SM) along with DEM which will enhance security in Grid. It is expected that this paper will provide a better understanding of the technologies, potential advantages and research challenges of the smart grid and provoke interest among the research community to further explore this promising research area.

  7. Q-balls in atomic Bose-Einstein condensates

    CERN Document Server

    Enqvist, K

    2003-01-01

    Relativistic scalar field theories with a conserved global charge Q often possess (meta)stable spherically symmetric soliton solutions, called Q-balls. We elaborate on the perfect formal analogy which exists between Q-balls, and spherically symmetric solitons in certain non-relativistic atomic Bose-Einstein condensates, for which the dominant interatomic interaction can be tuned attractive. The stability of such atomic Q-balls depends on higher-order interatomic interactions, which can render the Q-balls absolutely stable for large Q. In a harmonic trap, present in existing experiments, the Q-ball solution is modified in an essential way. If the trap is significantly prolongated in one direction, however, then genuine solitons do appear, and some of the Q-ball properties studied in a relativistic cosmological context, such as their formation and collisions, can also be addressed experimentally.

  8. The methodology of composing the exercises system with fit balls.

    Directory of Open Access Journals (Sweden)

    Voronov N.P.

    2011-02-01

    Full Text Available The original methodology of composing the exercises system with fit balls was considered. More than 10 publications were analysed. On the lesson with fit balls the problem was revealed. In the experiment took part 30 students at the age from 18 till 21. All the famous exercises were systematized. As a result, a big attractiveness and assimilability of the proposed complex was revealed. The effectiveness of the complex of physical exercises with fit balls for students was proved.

  9. AN INNOVATIVE METHOD FOR FORMING BALLS FROM SCRAP RAIL HEADS

    OpenAIRE

    Zbigniew Pater; Janusz Tomczak; Tomasz Bulzak

    2016-01-01

    The paper describes a new method for forming grinding media balls from scrap rail heads. This forming method involves the following operations: cutting the rail head to the desired length combined with lateral pressing of the produced workpiece; flashless die forging and sizing of balls in a helical impression. The proposed method was verified by numerical simulation which involved the modeling of a forming process for producing 80 mm diameter balls. As a result of the modeling, it was possib...

  10. Array tomography: imaging stained arrays.

    Science.gov (United States)

    Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J

    2010-11-01

    Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time-consuming and require some practice to perfect. In this protocol, tissue arrays are imaged using conventional wide-field fluorescence microscopy. Images can be captured manually or, with the appropriate software and hardware, the process can be automated. PMID:21041399

  11. Array tomography: production of arrays.

    Science.gov (United States)

    Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J

    2010-11-01

    Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time consuming and require some practice to perfect. This protocol describes the sectioning of embedded tissues and the mounting of the serial arrays. The procedures require some familiarity with the techniques used for ultramicrotome sectioning for electron microscopy. PMID:21041397

  12. The Grid : english version

    CERN Multimedia

    Rosy Mondardini Producer

    2003-01-01

    The Grid : . Sharing resources owned by many different organizations to access remote computers, software, and data efficiently and automatically . Secure access to establish the identity of a user or resource, after defining conditions under which sharing occurs . Bridging distance using high-speed connections between computers to create a global Grid . Open standards to allow applications designed for one Grid to run on all others

  13. Interpolating sliding mode observer for a ball and beam system

    Science.gov (United States)

    Luai Hammadih, Mohammad; Hosani, Khalifa Al; Boiko, Igor

    2016-09-01

    A principle of interpolating sliding mode observer is introduced in this paper. The observer incorporates multiple linear observers through interpolation of multiple estimates, which is treated as a type of adaptation. The principle is then applied to the ball and beam system for observation of the slope of the beam from the measurement of the ball position. The linearised model of the ball and beam system using multiple linearisation points is developed. The observer dynamics implemented in Matlab/Simulink Real Time Workshop environment. Experiments conducted on the ball and beam experimental setup demonstrate excellent performance of the designed novel interpolating (adaptive) observer.

  14. Fourier-Laguerre transform, convolution and wavelets on the ball

    CERN Document Server

    McEwen, J D

    2013-01-01

    We review the Fourier-Laguerre transform, an alternative harmonic analysis on the three-dimensional ball to the usual Fourier-Bessel transform. The Fourier-Laguerre transform exhibits an exact quadrature rule and thus leads to a sampling theorem on the ball. We study the definition of convolution on the ball in this context, showing explicitly how translation on the radial line may be viewed as convolution with a shifted Dirac delta function. We review the exact Fourier-Laguerre wavelet transform on the ball, coined flaglets, and show that flaglets constitute a tight frame.

  15. Accuracy and Reliability of a New Tennis Ball Machine

    OpenAIRE

    Cyril Brechbuhl, Grégoire Millet, Laurent Schmitt

    2016-01-01

    The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30...

  16. LOW COMPRESSION TENNIS BALLS AND SKILL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    John Hammond

    2006-12-01

    Full Text Available Coaching aims to improve player performance and coaches have a number of coaching methods and strategies they use to enhance this process. If new methods and ideas can be determined to improve player performance they will change coaching practices and processes. This study investigated the effects of using low compression balls (LCBs during coaching sessions with beginning tennis players. In order to assess the effectiveness of LCBs on skill learning the study employed a quasi-experimental design supported by qualitative and descriptive data. Beginner tennis players took part in coaching sessions, one group using the LCBs while the other group used standard tennis balls. Both groups were administered a skills at the beginning of a series of coaching sessions and again at the end. A statistical investigation of the difference between pre and post-test results was carried out to determine the effect of LCBs on skill learning. Additional qualitative data was obtained through interviews, video capture and the use of performance analysis of typical coaching sessions for each group. The skill test results indicated no difference in skill learning when comparing beginners using the LCBs to those using the standard balls. Coaches reported that the LCBs appeared to have a positive effect on technique development, including aspects of technique that are related to improving power of the shot. Additional benefits were that rallies went on longer and more opportunity for positive reinforcement. In order to provide a more conclusive answer to the effects of LCBs on skill learning and technique development recommendations for future research were established including a more controlled experimental environment and larger sample sizes across a longer period of time

  17. GRID Activities in ALICE

    Institute of Scientific and Technical Information of China (English)

    P.Cerello; T.Anticic; 等

    2001-01-01

    The challenge of LHC computing,with data rates in the range of several PB/year,requires the development of GRID technologies,to optimize the exploitation of distributed computing power and the authomatic access to distributed data storage.In the framework of the EU-DataGrid project,the ALICE experiment is one of the selected test applications for the early development and implementation of GRID Services.Presently,about 15 ALICE sites are makin use of available GRID tools and a large scale test production involving 9 of them was carried out with our simulation program.Results are discussed in detail,as well as future plans.

  18. The scintillating grid illusion.

    Science.gov (United States)

    Schrauf, M; Lingelbach, B; Wist, E R

    1997-04-01

    Disk-shaped luminance increments were added to the intersections of a Hermann grid consisting of medium grey bars on a black background. Illusory spots, darker than the background, were perceived as flashing within the white disks with each flick of the eye. This striking phenomenon may be referred to as the scintillating grid illusion. We determined the conditions necessary for cancelling the Hermann grid illusion, as well as the luminance requirements and the size ratio between disks and bars that elicits the scintillation effect. The fact that scanning eye movements are necessary to produce the scintillation effect sets it apart from the Hermann grid illusion.

  19. 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.

  20. Ball Bearing Analysis with the ORBIS Tool

    Science.gov (United States)

    Halpin, Jacob D.

    2016-01-01

    Ball bearing design is critical to the success of aerospace mechanisms. Key bearing performance parameters, such as load capability, stiffness, torque, and life all depend on accurate determination of the internal load distribution. Hence, a good analytical bearing tool that provides both comprehensive capabilities and reliable results becomes a significant asset to the engineer. This paper introduces the ORBIS bearing tool. A discussion of key modeling assumptions and a technical overview is provided. Numerous validation studies and case studies using the ORBIS tool are presented. All results suggest the ORBIS code closely correlates to predictions on bearing internal load distributions, stiffness, deflection and stresses.

  1. Quenching simulation of steel grinding balls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata-Hernandez, O.; Reyes, L. A.; Camurri, C.; Carrasco, C.; Garza-Monte-de-Oca, F.; Colas, R.

    2015-07-01

    The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses. (Author)

  2. Collective flow measured with the Plastic Ball

    International Nuclear Information System (INIS)

    The experimental results from the Plastic Ball detector have contributed vastly to the understanding of the reaction mechanism of nuclear collisions at several hundred MeV per nucleon. The discovery of the collective flow phenomena (bounce-off of spectator fragments, side-splash in the reaction plane, and squeeze-out out of the reaction plane), as they were predicted by hydrodynamical models, has led to the experimental observation of compressed nuclear matter, which is a necessary condition before one can study the equation of state in detail and search for phase transitions at higher energies. 39 refs., 9 figs., 1 tab

  3. Observation of Lightning Ball (Ball Lightning): A new phenomenological description of the phenomenon

    CERN Document Server

    Tar, Domokos

    2009-01-01

    The author (physicist)has observed the very strange,beautiful and frightening Lightning Ball (LB). He has never forgotten this phenomenon. During his working life he could not devote himself to the problem of LB-formation.Only two years ago as he has been reading different unbelievable models of LB-formation, he decided to work on this problem. By studying the literature and the crucial points of his observation the author succeeded in creating a completely new model of Lightning Ball(LB) and Ball Lightning(BL)-formation based on the symmetry breaking of the hydrodynamic vortex ring.This agrees fully with the observation and overcomes the shortcomings of current models of LB formation. This model provides answers to the questions: Why are LBs so rarely observed,why do BLs in rare cases have such a high energy and how can we generate LB in the laboratory? Moreover the author differentiates between LB and BL, the latter having a high energy and occuring in 5 % of the observations. Keywords: ball lightning, hydr...

  4. Memory in random bouncing ball dynamics

    CERN Document Server

    Zouabi, C; Perret-Liaudet, J

    2016-01-01

    The bouncing of an inelastic ball on a vibrating plate is a popular model used in various fields, from granular gases to nanometer-sized mechanical contacts. For random plate motion, so far, the model has been studied using Poincar{\\'e} maps in which the excitation by the plate at successive bounces is assumed to be a discrete Markovian (memoryless) process. Here, we investigate numerically the behaviour of the model for continuous random excitations with tunable correlation time. We show that the system's dynamics are controlled by the ratio of the Markovian mean flight time of the ball and the mean time between successive peaks in the motion of the exciting plate. When this ratio, which depends on the bandwidth of the excitation signal, exceeds a certain value, the Markovian approach is appropriate; below, memory of preceding excitations arises, leading to a significant decrease of the jump duration; at the smallest values of the ratio, chattering occurs. Overall, our results open the way for uses of the mo...

  5. Ion implantation of silicon nitride ball bearings

    Energy Technology Data Exchange (ETDEWEB)

    Williams, J.M. [Oak Ridge National Lab., TN (United States); Miner, J.R. [United Technologies, Pratt and Whitney, West Palm Beach, FL (United States)

    1996-09-01

    Hypothesis for ion implantation effect was that stress concentrations reflected into the bulk due to topography such as polishing imperfections, texture in the race, or transferred material, might be reduced due to surface amorphization. 42 control samples were tested to an intended runout period of 60 h. Six ion implanted balls were tested to an extended period of 150 h. Accelerated testing was done in a V groove so that wear was on two narrow wear tracks. Rutherford backscattering, XRPS, profilometry, optical microscopy, nanoindentation hardness, and white light interferometry were used. The balls were implanted with 150-keV C ions at fluence 1.1x10{sup 17}/cm{sup 2}. The samples had preexisting surface defects (C-cracks), so the failure rate of the control group was unacceptable. None of the ion-implanted samples failed in 150 h of testing. Probability of randomly selecting 6 samples from the control group that would perform this well is about 5%, so there is good probability that ion implantation improved performance. Possible reasons are discussed. Wear tracks, microstructure, and impurity content were studied in possible relation to C-cracks.

  6. Global Inventory and Analysis of Smart Grid Demonstration Projects

    Energy Technology Data Exchange (ETDEWEB)

    Mulder, W.; Kumpavat, K.; Faasen, C.; Verheij, F.; Vaessen, P [DNV KEMA Energy and Sustainability, Arnhem (Netherlands)

    2012-10-15

    As the key enabler of a more sustainable, economical and reliable energy system, the development of smart grids has received a great deal of attention in recent times. In many countries around the world the benefits of such a system have begun to be investigated through a number of demonstration projects. With such a vast array of projects it can be difficult to keep track of changes, and to understand which best practices are currently available with regard to smart grids. This report aims to address these issues through providing a comprehensive outlook on the current status of smart grid projects worldwide.

  7. Infrared-Bolometer Arrays with Reflective Backshorts

    Science.gov (United States)

    Miller, Timothy M.; Abrahams, John; Allen, Christine A.

    2011-01-01

    Integrated circuits that incorporate square arrays of superconducting-transition- edge bolometers with optically reflective backshorts are being developed for use in image sensors in the spectral range from far infrared to millimeter wavelengths. To maximize the optical efficiency (and, thus, sensitivity) of such a sensor at a specific wavelength, resonant optical structures are created by placing the backshorts at a quarter wavelength behind the bolometer plane. The bolometer and backshort arrays are fabricated separately, then integrated to form a single unit denoted a backshort-under-grid (BUG) bolometer array. In a subsequent fabrication step, the BUG bolometer array is connected, by use of single-sided indium bump bonding, to a readout device that comprises mostly a superconducting quantum interference device (SQUID) multiplexer circuit. The resulting sensor unit comprising the BUG bolometer array and the readout device is operated at a temperature below 1 K. The concept of increasing optical efficiency by use of backshorts at a quarter wavelength behind the bolometers is not new. Instead, the novelty of the present development lies mainly in several features of the design of the BUG bolometer array and the fabrication sequence used to implement the design. Prior to joining with the backshort array, the bolometer array comprises, more specifically, a square grid of free-standing molybdenum/gold superconducting-transition-edge bolometer elements on a 1.4- m-thick top layer of silicon that is part of a silicon support frame made from a silicon-on-insulator wafer. The backshort array is fabricated separately as a frame structure that includes support beams and contains a correspond - ing grid of optically reflective patches on a single-crystal silicon substrate. The process used to fabricate the bolometer array includes standard patterning and etching steps that result in the formation of deep notches in the silicon support frame. These notches are designed to

  8. 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 ...

  9. Planning in smart grids

    NARCIS (Netherlands)

    Bosman, Maurice Gerardus Clemens

    2012-01-01

    Thee electricity supply chain is changing, due to increasing awareness for sustainability and an improved energy efficiency. The traditional infrastructure where demand is supplied by centralized generation is subject to a transition towards a Smart Grid. In this Smart Grid, sustainable generation f

  10. Security for grids

    Energy Technology Data Exchange (ETDEWEB)

    Humphrey, Marty; Thompson, Mary R.; Jackson, Keith R.

    2005-08-14

    Securing a Grid environment presents a distinctive set of challenges. This paper groups the activities that need to be secured into four categories: naming and authentication; secure communication; trust, policy, and authorization; and enforcement of access control. It examines the current state of the art in securing these processes and introduces new technologies that promise to meet the security requirements of Grids more completely.

  11. The play grid

    DEFF Research Database (Denmark)

    Fogh, Rune; Johansen, Asger

    2013-01-01

    In this paper we propose The Play Grid, a model for systemizing different play types. The approach is psychological by nature and the actual Play Grid is based, therefore, on two pairs of fundamental and widely acknowledged distinguishing characteristics of the ego, namely: extraversion vs. intro...

  12. Launch Creativity with Ping-Pong Ball Challenge

    Science.gov (United States)

    Kornoelje, Joanne; Roman, Harry T.

    2011-01-01

    Educators at Thomas A. Edison Middle School have worked together to bring invention information and activities to life. One activity in particular, Ping-Pong Ball Invention Challenge, has proven a great success. The Ping-Pong Ball Invention Challenge was inspired by the basic rules for PBS's "Design Squad"'s "Pop Fly" activity. In this article,…

  13. Motion of a Ball on a Moving Surface

    Science.gov (United States)

    Cross, Rod

    2016-01-01

    A well-known physics demonstration is to pull a tablecloth rapidly from under some crockery without disturbing the crockery. An interesting question is whether the same result can be expected if the crockery is replaced by a ball, given that the ball might roll backwards on the tablecloth. Theoretical and experimental results are presented showing…

  14. Physical Activity Benefits Creativity: Squeezing a Ball for Enhancing Creativity

    Science.gov (United States)

    Kim, JongHan

    2015-01-01

    Studies in embodied cognition show that physical sensations, such as touch and movement, influence cognitive processes. Two studies were conducted to test whether squeezing a soft versus a hard ball facilitates different types of creativity. Squeezing a malleable ball would increase divergent creativity by catalyzing multiple or alternative ideas,…

  15. Wear numbers for ball cup and journal bearings

    NARCIS (Netherlands)

    Ligterink, D.J.; Moes, H.

    1980-01-01

    A wear number is defined for ball cup bearings and for journal bearings where the cup and the cylindrical bearing are made of soft material. This dimensionless wear number provides a relation between the following five quantities: the radius of the ball or the length of the journal bearing in millim

  16. Hardening treatment of friction surfaces of ball journal bearings

    Science.gov (United States)

    Gorlenko, A. O.; Davidov, S. V.

    2016-04-01

    The article presents the technology of finishing plasma hardening by the application of the multi-layer nanocoating Si-O-C-N system to harden the friction surfaces of the ball journal bearings. The authors of the paper have studied the applied wear-resistant anti-friction coating tribological characteristics, which determine the increase in wear resistance of the ball journal bearings.

  17. [First clinical experiences with ceramic ball attachments for overdentures].

    Science.gov (United States)

    Büttel, Adrian E; Schmidli, Fredy; Marinello, Carlo P; Lüthy, Heinz

    2008-01-01

    In this prospective clinical study on 40 patients with similar clinical conditions (edentulous jaw with 2 interforaminal implants) commercially available ceramic ball attachments (ruby) were compared to commercial titanium ball attachments. The primary aim of the study was to measure the wear of the ball attachments after being 1 year in function. However, in the course of the study already after 7 to 12 months multiple failures with ceramic ball attachments occurred. Twelve (28%) of 43 ceramic ball attachments had to be replaced, mostly because of fractures (8) of the ceramic ball. It seems that ceramic ball attachments of the investigated design are not able to withstand normal intraoral stresses. The short-term susceptibility to fractures didn't allow to examine the ceramic-inherent features such as compressive strength and wear resistance. Furthermore, a secure connection between a titan base and a ceramic ball seems to be challenging. Based on these results, in implant-retained removable prosthesis the use of metal-based retainers is still recommended, although during maintenance a higher wear has to be expected. This wear can be compensated by either activating or changing the matrix or the patrix. PMID:18293602

  18. On a Simple Formulation of the Golf Ball Paradox

    Science.gov (United States)

    Pujol, O.; Perez, J. Ph.

    2007-01-01

    The motion of a ball rolling without slipping on the lateral section inside a fixed vertical cylinder is analysed in the Earth referential frame which is assumed to be Galilean. Equations of motion are rapidly obtained and the golf ball paradox is understood: these equations describe a motion consisting of a vertical harmonic oscillation related…

  19. Exact solutions, energy, and charge of stable Q-balls

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Marques, M.A. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil); Menezes, R. [Universidade Federal da Paraiba, Departamento de Ciencias Exatas, Rio Tinto, PB (Brazil); Universidade Federal de Campina Grande, Departamento de Fisica, Campina Grande, PB (Brazil)

    2016-05-15

    In this work we deal with nontopological solutions of the Q-ball type in two spacetime dimensions. We study models of current interest, described by a Higgs-like and other, similar potentials which unveil the presence of exact solutions. We use the analytic results to investigate how to control the energy and charge to make the Q-balls stable. (orig.)

  20. DUAL BASES FOR A NEW FAMILY OF GENERALIZED BALL BASES

    Institute of Scientific and Technical Information of China (English)

    Hong-yiWu

    2004-01-01

    This paper presents the dual bases for a new family of generalized Ball curves with a position parameter K, which includes the Bezier curve, generalized Said-Ball curve and some intermediate curves. Using the dual bases, the relative Marsden identity, conversion formulas of bases and control points of various curves are obtained.

  1. The Net Physiological Cost of Dribbling a Soccer Ball.

    Science.gov (United States)

    Reilly, Thomas; Ball, David

    1984-01-01

    To establish the net energy cost of dribbling a soccer ball, eight males ran on a treadmill while dribbling a ball against a rebound box. Oxygen uptake, perceived exertion, and blood lactate levels were measured and compared with results from subjects running without dribbling. Results are discussed. (Author/DF)

  2. Electrochemical corrosion of steel balls in wet grinding

    Institute of Scientific and Technical Information of China (English)

    谢恒星; 李松仁; 李定或

    2003-01-01

    Rest potentials for the steel ball electrode and the pyrite electrode as well as the combination potentials and the galvanic currents developed in the pyrite-steel ball couple were measured. The data demonstrate that the galvanic couples are going to form between the pyrite particles and the steel balls when they contact with each other. The initial combination potential and the initial galvanic current of the pyrite-ball couple while bubbling with oxygen are greater than those in aeration of air. The combination potential and the galvanic current decrease more quickly with time while bubbling with oxygen than they do in aeration of air. In an experiment of simulating wear differences, a galvanic current, which is smaller than that developed in the pyrite-ball couple, exists between two different ball electrodes in wear degree on the surface of them. Under different grinding time conditions, the equivalent corrosion current density calculated from marked ball wear data by applying Faraday's law correlates well with those estimated from polarization curves of pyrite and ball electrodes, and the former is always greater than the latter.

  3. Structure and magnetism of SmCo5 nanoflakes prepared by surfactant-assisted ball milling with different ball sizes

    International Nuclear Information System (INIS)

    Anisotropic magnetic SmCo5 nanoflakes have been fabricated by surfactant-assisted ball milling (SABM) using hardened steel balls of one of the following sizes: 4, 6.5, 9.5 and 12.7 mm in diameters. The magnetic properties of SmCo5 particles prepared by SABM with different milling ball sizes in diameters were investigated systematically. It was showed that the nanoflakes milled by amount of small size balls had a higher coercivity and lower anisotropy, i.e., worse grain orientation although in a short milling time while the nanoflakes prepared with same weight of big balls tend to have a lower coercivity, better grain orientation. The coercivity mechanism of the nanoflake was studied and it was mainly dominated with the domain-wall pinning. The SEM analysis shows that the morphology of nanoflakes prepared with different ball sizes are almost the same when the balls to powder weight ratio is fixed. The different magnetic properties caused by different ball sizes are mainly due to the different microstructure changes, i.e, grain refinement and c-axis orientation, which are demonstrated by X-ray diffraction (XRD) analysis and transmission electron microscope (TEM). Based on the experiments above, a combined milling process was suggested and done to improve magnetic properties as your need. - Highlights: • We fabricated anisotropic magnetic SmCo5 nanoflakes by surfactant-assisted ball milling (SABM). • We investigated the magnetic properties of SmCo5 particles systematically. It was showed that the coercivity, high or low, and grain orientation, good or bad, were influenced strongly by balls size. The different magnetisms caused by different ball sizes is mainly due to the different microstructure changes. • The coercivity mechanism of the nanoflake was studied and it was mainly dominated with the domain-wall pinning

  4. HIRENASD Unstructured Grids - VGRID software

    Data.gov (United States)

    National Aeronautics and Space Administration — These grids were constructed using VGRID software from NASA Langley. The grids designed for node based (labeled 'nc') and cell-centered solvers are supplied. Grids...

  5. BSCW Unstructured Grids - VGRID software

    Data.gov (United States)

    National Aeronautics and Space Administration — These grids were constructed using VGRID software from NASA Langley. The grids designed for node based (labeled 'nc') and cell-centered solvers are supplied. Grids...

  6. Improved hydrogen sorption kinetics in wet ball milled Mg hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Li

    2011-05-04

    In this work, wet ball milling method is used in order to improve hydrogen sorption behaviour due to its improved microstructure of solid hydrogen materials. Compared to traditional ball milling method, wet ball milling has benefits on improvement of MgH{sub 2} microstructure and further influences on its hydrogen sorption behavior. With the help of solvent tetrahydrofuran (THF), wet ball milled MgH{sub 2} powder has much smaller particle size and its specific surface area is 7 times as large as that of dry ball milled MgH{sub 2} powder. Although after ball milling the grain size is decreased a lot compared to as-received MgH{sub 2} powder, the grain size of wet ball milled MgH{sub 2} powder is larger than that of dry ball milled MgH{sub 2} powder due to the lubricant effect of solvent THF during wet ball milling. The improved particle size and specific surface area of wet ball milled MgH{sub 2} powder is found to be determining its hydrogen sorption kinetics especially at relatively low temperatures. And it also shows good cycling sorption behavior, which decides on its industrial applicability. With three different catalysts MgH{sub 2} powder shows improved hydrogen sorption behavior as well as the cyclic sorption behavior. Among them, the Nb{sub 2}O{sub 5} catalyst is found to be the most effective one in this work. Compared to the wet ball milled MgH{sub 2} powder, the particle size and specific surface area of the MgH{sub 2} powder with catalysts are similar to the previous ones, while the grain size of the MgH{sub 2} with catalysts is much finer. In this case, two reasons for hydrogen sorption improvement are suggested: one is the reduction of the grain size. The other may be as pointed out in some literatures that formation of new oxidation could enhance the hydrogen sorption kinetics, which is also the reason why its hydrogen capacity is decreased compared to without catalysts. After further ball milling, the specific surface area of wet ball milled Mg

  7. Effectiveness during ball screens in elite basketball games.

    Science.gov (United States)

    Gómez, Miguel-Ángel; Battaglia, Otavio; Lorenzo, Alberto; Lorenzo, Jorge; Jiménez, Sergio; Sampaio, Jaime

    2015-01-01

    Ball screens are one of the most frequently used tactical behaviour in elite basketball games. The aim of the present study was to identify their predictors of success related to time, space, players, and tasks performed. The sample was composed of 818 ball screens corresponding to 20 close games (mean differences in score of 3.1 ± 0.8 points) randomly selected from the playoff games of the Spanish Basketball League (2008-2011). Classification tree analysis (CHAID) was used to analyse which variable or combination of variables, better predicts effectiveness during ball screens. The main results allowed identifying interactions with dribbler actions after the screen and the orientation of the screen on the ball. The results showed no interaction with game quarter and quarter minute temporal-related variables in both analyses. The present findings allow improving coaches' strategic plans that involve selecting the most appropriate offensive approach when performing ball screens.

  8. Accuracy and Reliability of a New Tennis Ball Machine

    Directory of Open Access Journals (Sweden)

    Cyril Brechbuhl, Grégoire Millet, Laurent Schmitt

    2016-06-01

    Full Text Available The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min-1. The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m. The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency. The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h-1 for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1. Conclusion: both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training.

  9. The PANDA Grid

    International Nuclear Information System (INIS)

    In order to fulfill the computing demands of the future PANDA experiment at FAIR in Darmstadt a dedicated computing infrastructure will be required. A conceivable way of acquiring and managing the necessary computing power for simulations and data analysis is the Grid model. As an alternative to a centralized computing center this model allows to pool independent resources from multiple institutes or organizations. Although PANDA is not expected to acquire data before the year 2016 the PANDA collaboration is already experimenting with the PANDA Grid. The PANDA Grid uses the AliEn middleware which is entirely built around Open Source components and has been developed by the ALICE collaboration at CERN. The PANDA Grid currently consists of 10 sites. Due to the optimized installation procedures and portability of the AliEn software it is easy to add new resources, allowing the Grid to be expanded without disturbing its continuous operation. AliEn provides tools to pool hardware resources but also to manage the installation of common software packages. This feature is exploited to distribute, install, and update the PANDA analysis software (PandaRoot) on the different sites and with this to enable the PANDA Grid to perform PANDA related tasks. It is intended that PANDA Grid will provide in the order of 2-3000 CPUs by the end of 2008 and then constitute a powerful tool for upcoming PANDA detector design and physics case studies.

  10. A Theoretical Analysis of Ball Spinning

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    As a special method of manufacturing thin wall tubes, the ball spinning process has been used for nearly 30 years because of its less investment of equipment, higher precision, and more perfect properties of products. However, the application is limited since the process parameters are determined based on empirical data and laboratory experiments for lack of a whole theoretical analysis. In this paper, some basic parameters such as the force and power parameters have been studied based on an analysis of geometry and mechanics of the process. The calculation of forming forces and the selection of the working angle are carried out. At the end, a perfect comparison between the results of the experiments and the theoretical analysis is made.

  11. 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

  12. Instant 960 Grid System

    CERN Document Server

    Tres, Diego

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. Instant 960 Grid System uses step-by-step instructions, covering the basic understanding needed to create a quick, high quality responsive website prototype using the 960 Grid System.The book is intended for beginner web developers and information architects looking to create a quick responsive website prototype. Basic knowledge of web development and a little understanding of grids is encouraged.

  13. 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

  14. Interactive volume visualization of general polyhedral grids

    KAUST Repository

    Muigg, Philipp

    2011-12-01

    This paper presents a novel framework for visualizing volumetric data specified on complex polyhedral grids, without the need to perform any kind of a priori tetrahedralization. These grids are composed of polyhedra that often are non-convex and have an arbitrary number of faces, where the faces can be non-planar with an arbitrary number of vertices. The importance of such grids in state-of-the-art simulation packages is increasing rapidly. We propose a very compact, face-based data structure for representing such meshes for visualization, called two-sided face sequence lists (TSFSL), as well as an algorithm for direct GPU-based ray-casting using this representation. The TSFSL data structure is able to represent the entire mesh topology in a 1D TSFSL data array of face records, which facilitates the use of efficient 1D texture accesses for visualization. In order to scale to large data sizes, we employ a mesh decomposition into bricks that can be handled independently, where each brick is then composed of its own TSFSL array. This bricking enables memory savings and performance improvements for large meshes. We illustrate the feasibility of our approach with real-world application results, by visualizing highly complex polyhedral data from commercial state-of-the-art simulation packages. © 2011 IEEE.

  15. Dosimetric properties of megavoltage grid therapy

    International Nuclear Information System (INIS)

    Purpose: Grid therapy is a technique used to deliver a high dose of radiation (15-20 Gy) in a single fraction to many small volumes within a large treatment field. This treatment modality is used for the palliative treatment of large, deeply seated tumors, which have either been treated to tolerance with conventional radiation, or, due to massive tumor bulk, would most likely not benefit from a conventional course of radiation therapy. As the dose distribution from megavoltage grid therapy differs significantly from that of conventional radiation therapy (i.e., many large dose gradients exist within the tumor volume), we have measured various dosimetric properties inherent in this unique treatment modality. Methods and Materials: The grid is a 16 x 16 array of 1-cm diameter holes in a 7-cm thick piece of custom blocking material. The ratio of shielded to open surface area is 1:1. Depth dose, valley-to-peak ratios, and output factors for this square array grid were measured in a water phantom for several field sizes, as well as for a 1-cm diameter narrow beam using 6 MV and 25 MV photon beams. Results: The depth dose curves for the grid fields lie between those for an open portal and a narrow beam. For the 6-MV beam at dmax, the ratios of the doses delivered to the center of the shielded regions to that under the center of the holes, expressed as valley-to-peak ratios, range from 15 to 40%. At 10 cm, the ratios increase to between 25 and 45%. At 25 MV at both dmax and 10 cm, the valley-to-peak ratios are between 40 and 60%. The output factors, 0.89 for 6 MV and 0.77 for 25 MV, do not depend on field size. Conclusion: Megavoltage grid therapy is a unique treatment modality where the dose is delivered differentially to a large volume in one fraction. Characterization of the dosimetric properties has allowed clinical implementation of the grid

  16. US National Grid

    Data.gov (United States)

    Kansas Data Access and Support Center — This is a polygon feature data layer of United States National Grid (1000m x 1000m polygons ) constructed by the Center for Interdisciplinary Geospatial Information...

  17. Smart Grid Architectures

    DEFF Research Database (Denmark)

    Dondossola, Giovanna; Terruggia, Roberta; Bessler, Sandford;

    2014-01-01

    The scope of this paper is to address the evolution of distribution grid architectures following the widespread introduction of renewable energy sources. The increasing connection of distributed resources has a strong impact on the topology and the control functionality of the current distributio...... with existing communication networks. The objective of the European FP7 project SmartC2Net in this regard is to enable robust smart grid control utilizing heterogeneous third party communication infrastructures.......The scope of this paper is to address the evolution of distribution grid architectures following the widespread introduction of renewable energy sources. The increasing connection of distributed resources has a strong impact on the topology and the control functionality of the current distribution...... grids requiring the development of new Information and Communication Technology (ICT) solutions with various degrees of adaptation of the monitoring, communication and control technologies. The costs of ICT based solutions need however to be taken into account, hence it is desirable to work...

  18. Grid Computing Education Support

    Energy Technology Data Exchange (ETDEWEB)

    Steven Crumb

    2008-01-15

    The GGF Student Scholar program enabled GGF the opportunity to bring over sixty qualified graduate and under-graduate students with interests in grid technologies to its three annual events over the three-year program.

  19. Technology Roadmaps: Smart Grids

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The development of Technology Roadmaps: Smart Grids -- which the IEA defines as an electricity network that uses digital and other advanced technologies to monitor and manage the transport of electricity from all generation sources to meet the varying electricity demands of end users -- is essential if the global community is to achieve shared goals for energy security, economic development and climate change mitigation. Unfortunately, existing misunderstandings of exactly what smart grids are and the physical and institutional complexity of electricity systems make it difficult to implement smart grids on the scale that is needed. This roadmap sets out specific steps needed over the coming years to achieve milestones that will allow smart grids to deliver a clean energy future.

  20. World Wide Grid

    CERN Multimedia

    Grätzel von Grätz, Philipp

    2007-01-01

    Whether for genetic risk analysis or 3D-rekonstruktion of the cerebral vessels: the modern medicine requires more computing power. With a grid infrastructure, this one can be if necessary called by the network. (4 pages)

  1. Lincoln Laboratory Grid

    Data.gov (United States)

    Federal Laboratory Consortium — The Lincoln Laboratory Grid (LLGrid) is an interactive, on-demand parallel computing system that uses a large computing cluster to enable Laboratory researchers to...

  2. RSW Cell Centered Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — New cell centered grids are generated to complement the node-centered ones uploaded. Six tarballs containing the coarse, medium, and fine mixed-element and pure...

  3. The Language Grid

    CERN Document Server

    Ishida, Toru

    2011-01-01

    This volume presents an overview of relevant research results and development involving the Language Grid -- an initiative to build an infrastructure where end users can create composite language services for intercultural collaboration.

  4. Grid in Geosciences

    Science.gov (United States)

    Petitdidier, Monique; Schwichtenberg, Horst

    2010-05-01

    The worldwide Earth science community covers a mosaic of disciplines and players such as academia, industry, national surveys, international organizations, and so forth. It provides a scientific basis for addressing societal issues, which require that the Earth science community utilize massive amounts of data, both in real and remote time. This data is usually distributed among many different organizations and data centers. These facts, the utilization of massive, distributed data amounts, explain the interest of the Earth science community for Grid technology, also noticeable by the variety of applications ported and tools developed. In parallel to the participation in EGEE, other projects involving ES disciplines were or have been carried out as related projects to EGEE (Enabling Grids for E-sciencE) such as CYCLOPS, SEEGrid, EELA2, EUASIA or outside e.g., in the framework of WGISS/CEOS. Numerous applications in atmospheric chemistry, meteorology, seismology, hydrology, pollution, climate and biodiversity were deployed successfully on Grid. In order to fulfill requirements of risk management, several prototype applications have been deployed using OGC (Open geospatial Consortium) components with Grid middleware. Examples are in hydrology for flood or Black Sea Catchment monitoring, and in fire monitoring. Meteorological, pollution and climate applications are based on meteorological models ported on Grid such as MM5 (Mesoscale Model), WRF (Weather Research and Forecasting), RAMS (Regional Atmospheric Modeling System) or CAM (Community Atmosphere Model). Seismological applications on Grid are numerous in locations where their occurrence is important and computer resources too small; then interfaces and gateways have been developed to facilitate the access to data and specific software and avoid work duplication. A portal has been deployed for commercial seismological software, Geocluster, for academic users. In this presentation examples of such applications will

  5. 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.

  6. Water Bouncing Balls: how material stiffness affects water entry

    Science.gov (United States)

    Truscott, Tadd

    2014-03-01

    It is well known that one can skip a stone across the water surface, but less well known that a ball can also be skipped on water. Even though 17th century ship gunners were aware that cannonballs could be skipped on the water surface, they did not know that using elastic spheres rather than rigid ones could greatly improve skipping performance (yet would have made for more peaceful volleys). The water bouncing ball (Waboba®) is an elastic ball used in a game of aquatic keep away in which players pass the ball by skipping it along the water surface. The ball skips easily along the surface creating a sense that breaking the world record for number of skips could easily be achieved (51 rock skips Russell Byers 2007). We investigate the physics of skipping elastic balls to elucidate the mechanisms by which they bounce off of the water. High-speed video reveals that, upon impact with the water, the balls create a cavity and deform significantly due to the extreme elasticity; the flattened spheres resemble skipping stones. With an increased wetted surface area, a large hydrodynamic lift force is generated causing the ball to launch back into the air. Unlike stone skipping, the elasticity of the ball plays an important roll in determining the success of the skip. Through experimentation, we demonstrate that the deformation timescale during impact must be longer than the collision time in order to achieve a successful skip. Further, several material deformation modes can be excited upon free surface impact. The effect of impact velocity and angle on the two governing timescales and material wave modes are also experimentally investigated. Scaling for the deformation and collision times are derived and used to establish criteria for skipping in terms of relevant physical parameters.

  7. Synthesis of porous carbon balls from spherical colloidal crystal templates.

    Science.gov (United States)

    Kim, Youngchan; Cho, Chang-Yeol; Kang, Ji-Hwan; Cho, Young-Sang; Moon, Jun Hyuk

    2012-07-17

    Spherical inverse opal (IO) porous carbon was produced utilizing silica colloidal crystal spheres as templates. The spherical colloidal crystals were obtained through the self-assembly of monodisperse particles inside an emulsion droplet with confined geometry. The templates were inverted using a carbon precursor, phenol-formaldehyde (PF) resol. We demonstrated a two-step synthesis involving the subsequent infiltration of the PF resol precursor into the spherical colloidal crystal template and a one-step synthesis using a silica colloidal solution containing dissolved PF resol. In the former case, the sizes of the IO carbon balls were controlled by the size of the colloidal crystal templates, and diameters of a few micrometers up to 50 μm were obtained. The average diameter of the macropores created by the silica particles was 230 nm. Moreover, meso-/macroporous IO carbon balls were created using block-copolymer templates in the PF resol. In the one-step synthesis, the concentration of PF resol in the colloidal solution controlled the diameter of the IO carbon balls. IO balls smaller than 3 μm were obtained from the direct addition of 5% PF resol. The one-step synthesis produced rather irregular porous structures reflecting the less ordered crystallization processes inside the spherical colloidal crystals. Nitrogen adsorption and cyclic voltammetry measurements were conducted to measure the specific area and electroactive surface area of the IO carbon balls. The specific area of the mesopores-incorporated IO carbon balls was 1.3 times higher than that of bare IO carbon balls. Accordingly, the meso-/macroporous porous carbon balls exhibited higher electrocatalytic properties than the macroporous carbon balls.

  8. Beyond grid security

    International Nuclear Information System (INIS)

    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

  9. Reference installation for the German grid initiative D-Grid

    Science.gov (United States)

    Buehler, W.; Dulov, O.; Garcia, A.; Jejkal, T.; Jrad, F.; Marten, H.; Mol, X.; Nilsen, D.; Schneider, O.

    2010-04-01

    The D-Grid reference installation is a test platform for the German grid initiative. The main task is to create the grid prototype for software and hardware components needed in the D-Grid community. For each grid-related task field different alternative middleware is included. With respect to changing demands from the community, new versions of the reference installation are released every six months.

  10. The effect of surface geometry on soccer ball trajectories

    OpenAIRE

    Barber, S.; Carré, M.J.

    2010-01-01

    Two different measurement techniques are used to examine the effect of surface geometry on soccer ball trajectories. Five professional players are observed using high-speed video when taking curling free kicks with four different soccer balls. The input conditions are measured and the average launch velocity and spin are found to be approximately 24 m/s and 106 rad/s. It is found that the players can apply more spin (~50%) on average to one ball, which has a slightly rougher surface than the ...

  11. [Locator or ball attachment: a guide for clinical decision making].

    Science.gov (United States)

    Büttel, Adrian E; Bühler, Nico M; Marinello, Carlo P

    2009-01-01

    Various attachments are available to retain overdentures on natural roots or implants. Technical aspects, the clinical handling, the capability to adapt or repair and the costs are parameters to be considered when choosing the appropriate attachment. Ball attachments and bars are clinically established and well documented. Ball attachments as prefabricated, unsplinted units are easily replaceable and show hygienic advantages, while bars show favorable stability. The Locator is a newer, popular clinical alternative to these established attachments. The ball attachment and the Locator are compared from a technical and clinical point of view. PMID:19852208

  12. [Locator or ball attachment: a guide for clinical decision making].

    Science.gov (United States)

    Büttel, Adrian E; Bühler, Nico M; Marinello, Carlo P

    2009-01-01

    Various attachments are available to retain overdentures on natural roots or implants. Technical aspects, the clinical handling, the capability to adapt or repair and the costs are parameters to be considered when choosing the appropriate attachment. Ball attachments and bars are clinically established and well documented. Ball attachments as prefabricated, unsplinted units are easily replaceable and show hygienic advantages, while bars show favorable stability. The Locator is a newer, popular clinical alternative to these established attachments. The ball attachment and the Locator are compared from a technical and clinical point of view.

  13. Gas-discharge particle detector with ball-tipped anodes

    International Nuclear Information System (INIS)

    A new gas-discharge particle detector, whose anode is a set of balls 2mm in diameter is investigated. The chamber is blowing down by the argon-methane-methylal gas mixture with the ratio 3:1:1. The detector operates in the self-quenching streamer mode, has high efficiency and a wide counting characteristic plateau. The maximum counting rate of particles at one ball is ∼ 2.5x104 s-1. The ball-tipped anodes allow making reliable complex-shaped detectors. Two-coordinate detection of multiparticle events can be naturally organized in detectors like that

  14. Intraneural stimulation using 2D wire-microelectrode arrays: I. Experimental results

    NARCIS (Netherlands)

    Smit, J.P.A.; Rutten, W.L.C.

    1995-01-01

    A two-dimensional 24-channel wire-microelectrode array was inserted into the peroneal nerve of the rat during acute experiments. The electrodes in the array are on a regular grid of 6 by 4 electrodes; inter-electrode spacing is 120 ¿m. For each of the electrodes in the array the corresponding twitch

  15. GridOrbit public display

    DEFF Research Database (Denmark)

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

    2010-01-01

    the research taking place in the biology laboratory. This should promote contribu-tions to the grid, and thereby mediate the appropriation of the grid technology. GridOrbit visualizes the activity in the grid, shows information about the different active projects, and supports a messaging functionality where...

  16. 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.

  17. Home Area Networks and the Smart Grid

    Energy Technology Data Exchange (ETDEWEB)

    Clements, Samuel L.; Carroll, Thomas E.; Hadley, Mark D.

    2011-04-01

    With the wide array of home area network (HAN) options being presented as solutions to smart grid challenges for the home, it is time to compare and contrast their strengths and weaknesses. This white paper examines leading and emerging HAN technologies. The emergence of the smart grid is bringing more networking players into the field. The need for low consistent bandwidth usage differs enough from the traditional information technology world to open the door to new technologies. The predominant players currently consist of a blend of the old and new. Within the wired world Ethernet and HomePlug Green PHY are leading the way with an advantage to HomePlug because it doesn't require installing new wires. In the wireless the realm there are many more competitors but WiFi and ZigBee seem to have the most momentum.

  18. Smart Grid Integration Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Troxell, Wade [Colorado State Univ., Fort Collins, CO (United States)

    2011-12-22

    The initial federal funding for the Colorado State University Smart Grid Integration Laboratory is through a Congressionally Directed Project (CDP), DE-OE0000070 Smart Grid Integration Laboratory. The original program requested in three one-year increments for staff acquisition, curriculum development, and instrumentation all which will benefit the Laboratory. This report focuses on the initial phase of staff acquisition which was directed and administered by DOE NETL/ West Virginia under Project Officer Tom George. Using this CDP funding, we have developed the leadership and intellectual capacity for the SGIC. This was accomplished by investing (hiring) a core team of Smart Grid Systems engineering faculty focused on education, research, and innovation of a secure and smart grid infrastructure. The Smart Grid Integration Laboratory will be housed with the separately funded Integrid Laboratory as part of CSU's overall Smart Grid Integration Center (SGIC). The period of performance of this grant was 10/1/2009 to 9/30/2011 which included one no cost extension due to time delays in faculty hiring. The Smart Grid Integration Laboratory's focus is to build foundations to help graduate and undergraduates acquire systems engineering knowledge; conduct innovative research; and team externally with grid smart organizations. Using the results of the separately funded Smart Grid Workforce Education Workshop (May 2009) sponsored by the City of Fort Collins, Northern Colorado Clean Energy Cluster, Colorado State University Continuing Education, Spirae, and Siemens has been used to guide the hiring of faculty, program curriculum and education plan. This project develops faculty leaders with the intellectual capacity to inspire its students to become leaders that substantially contribute to the development and maintenance of Smart Grid infrastructure through topics such as: (1) Distributed energy systems modeling and control; (2) Energy and power conversion; (3

  19. Determination of Contact Time of Rubber Balls Using a Digital Oscilloscope

    Science.gov (United States)

    Wadhwa, Ajay

    2010-01-01

    We present a new method for determining the contact time of a rubber ball with the rebounding surface by using a sound-detecting electronic circuit and a digital storage oscilloscope. The rubber ball (a tennis ball or squash ball) is dropped from a known height onto a rigid surface and its contact time on first bounce is determined on the…

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

    International Nuclear Information System (INIS)

    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

  1. 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 for such......’ 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...

  2. 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 for such......' 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...

  3. Treatment of ASP produced water with hydrophilic fibre ball filtration

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The conventional treatment process cannot meet the need for treatment of produced water from alkaline/surfactant/polymer flooding( ASP produced water) in Daqing oilfield. In this study, a new type of hydrophilic fibre ball medium was developed through surface modification method. The hydrophilic property of the surface modified fibre ball was tested with ASP produced liquid at laboratory. The results showed that this fibre ball had higher oil degreasing efficiency. The surface components were also observed by Scanning Electron Microscope and X-ray Photoelectron Spectroscopy, the result showed that the hydrophilic fibre' s surface was covered by sulfonic group. Using hydrophilic fibre ball as filter medium, a new type of filter was designed to treat ASP produced water in pilot-scale experiments. The obtained results indicated that this type of filter had high capability and efficiency for the treatment of ASP produced water. This filter should have a better application prospect in oilfield produced water treatment.

  4. Confining rigid balls by mimicking quadrupole ion trapping

    CERN Document Server

    Fan, Wenkai; Wang, Sihui; Zhou, Huijun

    2016-01-01

    The rotating saddle not only is an interesting system that is able to trap a ball near its saddle point, but can also intuitively illustrate the operating principles of quadrupole ion traps in modern physics. Unlike the conventional models based on the mass-point approximation, we study the stability of a ball in a rotating-saddle trap using rigid-body dynamics. The stabilization condition of the system is theoretically derived and subsequently verified by experiments. The results are compared with the previous mass-point model, giving large discrepancy as the curvature of the ball is comparable to that of the saddle. We also point out that the spin angular velocity of the ball is analogous to the cyclotron frequency of ions in an external magnetic field utilized in many prevailing ion-trapping schemes.

  5. Nonlinear dynamic behaviors of ball bearing rotor system

    Institute of Scientific and Technical Information of China (English)

    WANG Li-qin; CUI Li; ZHENG De-zhi; GU Le

    2009-01-01

    Nonlinear forces and moments caused by ball bearing were calculated based on relationship of displacement and deflection and quasi-dynamic model of bearing. Five-DOF dynamic equations of rotor supported by ball bearings were estimated. The Newmark-β method and Newton-Laphson method were used to solve the equations. The dynamic characteristics of rotor system were studied through the time response, the phase portrait, the Poincar? maps and the bifurcation diagrams. The results show that the system goes through the quasiperiodic bifurcation route to chaos as rotate speed increases and there are several quasi-periodic regions and chaos regions. The amplitude decreases and the dynamic behaviors change as the axial load of ball bearing increases; the initial contact angle of ball bearing affects dynamic behaviors of the system obviously. The system can avoid non-periodic vibration by choosing structural parameters and operating parameters reasonably.

  6. AN INNOVATIVE METHOD FOR FORMING BALLS FROM SCRAP RAIL HEADS

    Directory of Open Access Journals (Sweden)

    Zbigniew Pater

    2016-09-01

    Full Text Available The paper describes a new method for forming grinding media balls from scrap rail heads. This forming method involves the following operations: cutting the rail head to the desired length combined with lateral pressing of the produced workpiece; flashless die forging and sizing of balls in a helical impression. The proposed method was verified by numerical simulation which involved the modeling of a forming process for producing 80 mm diameter balls. As a result of the modeling, it was possible to examine the changes in the workpiece shape during each forming operation, the variations in loads and torques, as well as the distribution of temperatures enabling performing another forming operation, i.e. quenching. The results confirm that the designed method can be used to produce balls.

  7. Transversal stability of the bouncing ball on a concave surface

    Science.gov (United States)

    Chastaing, J.-Y.; Pillet, G.; Taberlet, N.; Géminard, J.-C.

    2015-05-01

    A ball bouncing repeatedly on a vertically vibrating surface constitutes the famous "bouncing ball" problem, a nonlinear system used in the 1980s, and still in use nowadays, to illustrate the route to chaos by period doubling. In experiments, in order to avoid the ball escape that would be inevitable with a flat surface, a concave lens is often used to limit the horizontal motion. However, we observe experimentally that the system is not stable. The ball departs from the system axis and exhibits a pendular motion in the permanent regime. We propose theoretical arguments to account for the decrease of the growth rate and of the asymptotic-size of the trajectory when the frequency of the vibration is increased. The instability is very sensitive to the physics of the contacts, which makes it a potentially interesting way to study the collisions rules, or to test the laws used in numerical studies of granular matter.

  8. Constraints on self-interacting Q-ball dark matter

    CERN Document Server

    Enqvist, Kari; Multamaki, T P; Vilja, I

    2002-01-01

    We consider different types of Q-balls as self-interacting dark matter. For the Q-balls to act as the dark matter of the universe they should not evaporate, which requires them to carry very large charges; depending on the type, the minimum charge could be as high as Q \\sim 10^{33} or the Q-ball coupling to ordinary matter as small as \\sim 10^{-35}. The cross-section-to-mass ratio needed for self-interacting dark matter implies a mass scale of m \\sim O(1) MeV for the quanta that the Q-balls consist of, which is very difficult to achieve in the MSSM.

  9. An overview of Ball Aerospace cryogen storage and delivery systems

    Science.gov (United States)

    Marquardt, J.; Keller, J.; Mills, G.; Schmidt, J.

    2015-12-01

    Starting on the Gemini program in the 1960s, Beech Aircraft (now Ball Aerospace) has been designing and manufacturing dewars for a variety of cryogens including liquid hydrogen and oxygen. These dewars flew on the Apollo, Skylab and Space Shuttle spacecraft providing fuel cell reactants resulting in over 150 manned spaceflights. Since Space Shuttle, Ball has also built the liquid hydrogen fuel tanks for the Boeing Phantom Eye unmanned aerial vehicle. Returning back to its fuel cell days, Ball has designed, built and tested a volume-constrained liquid hydrogen and oxygen tank system for reactant delivery to fuel cells on unmanned undersea vehicles (UUVs). Herein past history of Ball technology is described. Testing has been completed on the UUV specific design, which will be described.

  10. Performance analysis of a grid-connected photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Sidrach-de-Cardona, M. [Universidad de Malaga (Spain). Dpto. Fisica Aplicado II; Lopez, L.M. [Universidad de Malaga (Spain). Dpto. Lenguajes y C. Computacion

    1999-02-01

    Grid-connected photovoltaic systems are required to introduce photovoltaic solar energy into urban areas. To analyze these systems, a 2.0 kW{sub p} power system has been installed at the University of Malaga, Spain. The array power output was estimated by using measured I-V curves for the installed modules with minimization of mismatch losses. The supplied grid energy and main performances are described. The effects on system yield of threshold-inverter and coupling losses of the inverter to the grid have been studied. During 1997, the system supplied 2678 kWh to the grid, i.e. the mean daily output, was 7.4 kWh. The annual performance ratio was 64.5% and the optimal value 67.9%. (author)

  11. Role of Dimples on Golf Ball

    Science.gov (United States)

    Choi, Jin

    2005-11-01

    It is an open question why the drag coefficient on golf ball remains nearly constant with increasing Reynolds number after its sharp decrease. In order to investigate this interesting phenomenon, we measure the drag, separation angle, wall pressure and streamwise velocity inside/outside dimples before main separation. When drag reduction occurs with dimples, the separation angle measured is nearly constant even with increasing Reynolds number. Also, the wall pressure distributions outside dimples are nearly the same at different Reynolds numbers, although those inside dimples vary depending on the Reynolds number. From the streamwise velocity measurement, it is found that dimples located at the angles of 65^o ˜90^o (three rows of dimples exist in our experimental setup) make an important role in changing flow characteristics. Inside one or two rows of dimples located at those angles, a small separation bubble exists and flow becomes quickly transitional and turbulent with reattachment. After the reattachment, the flow does not separate at the downstream dimples owing to fuller velocity profile. With dimples, the main separation occurs further downstream at 110 degree. This main separation angle does not change even with increasing Reynolds number, because downstream dimples do not make an important role in changing flow characteristics any more.

  12. Transport in rotary drums and ball mills

    International Nuclear Information System (INIS)

    This report contains investigations into the influence exerted by operating conditions, material properties and geometry of the apparatus and of the discharge plate on the transport behaviour of narrow quartz sand fractions in a model apparatus. The transport coefficients are determined in residence time experiments with Na-24-labelling. The dependence obtained between the transport coefficients and the experimental parameters permits a coherent interpretation if the assumption is made that the two types of transport occur in different phases of radial motion: Convection takes place during ascend while axial dispersion is generated in the falling and ranging process. Furthermore, a model has been developed for evaluating the throughput of rotary drums and ball mills, respectively; it is based on the assumption that the throughput is governed by the material flux through the discharge plate. The efflux takes place only in the ascending zone as a result of gravity and centrifugal forces acting parallel to the discharge plate. A deduced relationship describing the material flow through the discharge apertures in connection with the calculable zone of ascend leads to an expression allowing to determine the mass flow rate as a function of material properties, operating conditions and geometry of the discharge plate. A comparison between experimental and calculated data shows good agreement. (orig.)

  13. New electrosurgical ball electrode with nonstick properties

    Science.gov (United States)

    Rondinone, Joseph; Brassell, James; Miller, Scott A., III; Thorne, Jonathan O.; Rondinone, David M.; Safabash, Jason; Vega, Felix

    1998-04-01

    A new electrosurgical ball electrode (SilverBulletTM) has been developed for applying radiofrequency (RF) energy to fuse biological and other materials to tissue surfaces. Specifically, the electrode was developed for use in conjunction with the Fusion Medical Technologies, Inc. gelatin patch (RapiSealTM) for use in pulmonary surgery to seal air leaks, and in solid abdominal organ surgeries to provide hemostatic tamponade. The new electrode allows for the application of RF energy in contact mode without the problems of the electrode sticking to the gelatin patch or the underlying tissue. Designed for use with commercially available electrosurgical handpieces, the electrode consists of a stainless steel connector that fits into the hand- piece, and an electrode assembly made from silver that includes a shank region, and a tip extension extending distally from the shank region. The distal tip of the tip extension is rounded and has a length of about 10 mm. The uniqueness of this electrode is the shank region which has a cross sectional area that is larger than the tip extension. The shank region acts as a heat sink to draw away heat from the tip extension while the tip extension itself remains sufficiently small to access desired target sites and display the desired energy transfer properties. In addition to the physical design, the use of silver as the core element provides a material with high electrical and thermal conductivities. The bulk of the electrode is appropriately insulated.

  14. For smart electric grids

    International Nuclear Information System (INIS)

    The authors identify and discuss the main challenges faced by the French electric grid: the management of electricity demand and the needed improvement of energy efficiency, the evolution of consumer's state of mind, and the integration of new production capacities. They notably outline that France have been living until recently with an electricity abundance, but now faces the highest consumption peaks in Europe, and is therefore facing higher risks of power cuts. They also notice that the French energy mix is slowly evolving, and outline the problems raised by the fact that renewable energies which are to be developed, are decentralised and intermittent. They propose an overview of present developments of smart grids, and outline their innovative characteristics, challenges raised by their development and compare international examples. They show that smart grids enable a better adapted supply and decentralisation. A set of proposals is formulated about how to finance and to organise the reconfiguration of electric grids, how to increase consumer's responsibility for peak management and demand management, how to create the conditions of emergence of a European market of smart grids, and how to support self-consumption and the building-up of an energy storage sector

  15. Grid and Entrepreneurship Workshop

    CERN Multimedia

    2006-01-01

    The CERN openlab is organising a special workshop about Grid opportunities for entrepreneurship. This one-day event will provide an overview of what is involved in spin-off technology, with a special reference to the context of computing and data Grids. Lectures by experienced entrepreneurs will introduce the key concepts of entrepreneurship and review, in particular, the industrial potential of EGEE (the EU co-funded Enabling Grids for E-sciencE project, led by CERN). Case studies will be given by CEOs of European start-ups already active in the Grid and computing cluster area, and regional experts will provide an overview of efforts in several European regions to stimulate entrepreneurship. This workshop is designed to encourage students and researchers involved or interested in Grid technology to consider the entrepreneurial opportunities that this technology may create in the coming years. This workshop is organized as part of the CERN openlab student programme, which is co-sponsored by CERN, HP, ...

  16. A lightweight method for computing ball spin in real time

    OpenAIRE

    Cristina, Federico; Dapoto, Sebastián H.; Russo, Claudia Cecilia

    2007-01-01

    The present paper poses a new method for computing the rotation of a ball in sport training situations, when the ball is approaching the goal line. The proposed method significantly reduces the hardware requirements associated to the capture, as well as the computational complexity necessary to obtain the results. The system's objective is to improve the player's technique and training methodology, and it is treated within the scope of the Institute's research line on signal and image process...

  17. Wear numbers for ball cup and journal bearings

    OpenAIRE

    Ligterink, D.J.; Moes, H.

    1980-01-01

    A wear number is defined for ball cup bearings and for journal bearings where the cup and the cylindrical bearing are made of soft material. This dimensionless wear number provides a relation between the following five quantities: the radius of the ball or the length of the journal bearing in millimetres, the wear modulus in newtons per square millimetre, the maximum wear depth rate of the cup or the cylindrical bearing in millimetres per second, the force between the mating surfaces in newto...

  18. Ball Lens Fiber Optic Sensor based Smart Handheld Microsurgical Instrument

    OpenAIRE

    Song, Cheol; Gehlbach, Peter L.; Kang, Jin U.

    2013-01-01

    During freehand performance of vitreoretinal microsurgery the surgeon must perform precise and stable maneuvers that achieve surgical objectives and avoid surgical risk. Here, we present an improved smart handheld microsurgical tool which is based on a ball lens fiber optic sensor that utilizes common path swept source optical coherence tomography. Improvements include incorporation of a ball lens single mode fiber optic probe that increases the working angle of the tool to greater than 45 de...

  19. Formation of Combined Surface Features of Protrusion Array and Wrinkles atop Shape-Memory Polymer

    Science.gov (United States)

    Sun, L.; Zhao, Y.; Huang, W. M.; Tong, T. H.

    We demonstrate a simple and cost-effective approach to realize two combined surface features of different scales together, namely submillimeter-sized protrusion array and microwrinkles, atop a polystyrene shape-memory polymer. Two different types of protrusions, namely flat-top protrusion and crown-shaped protrusion, were studied. The array of protrusions was produced by the Indentation-Polishing-Heating (IPH) process. Compactly packed steel balls were used for making array of indents. A thin gold layer was sputter deposited atop the polymer surface right after polishing. After heating for shape recovery, array of protrusions with wrinkles on the top due to the buckling of gold layer was produced.

  20. On the quantum stability of Q-balls

    CERN Document Server

    Tranberg, Anders

    2014-01-01

    We consider the evolution and decay of Q-balls under the influence of quantum fluctuations. We argue that the most important effect of quantum fluctuations is the modification of the effective potential in which the Q-ball evolves. This effect is in addition to spontaneous decay into elementary particle excitations and decay into smaller Q-balls considered in the literature, which like most tunnelling processes are likely to be strongly suppressed. We exemplify the effect of quantum fluctuations in a particular model potential (quadratic + quartic + sextic couplings), where we implement the inhomogeneous Hartree approximation of quantum dynamics and solve for the evolution of Q-balls in 3+1 dimensions. We find that the stability range as a function of angular velocity $\\omega$ is modified significantly compared to the classical case, so that small-$\\omega$ Q-balls are less stable than in the classical limit, and large-$\\omega$ Q-balls are more stable. This can be understood qualitatively in a simple way.

  1. On the quantum stability of Q-balls

    Energy Technology Data Exchange (ETDEWEB)

    Tranberg, Anders [Faculty of Science and Technology, University of Stavanger,4036 Stavanger (Norway); Weir, David J. [Department of Physics and Helsinki Institute of Physics,PL 64 (Gustaf Hällströmin katu 2), FI-00014 University of Helsinki (Finland)

    2014-04-30

    We consider the evolution and decay of Q-balls under the influence of quantum fluctuations. We argue that the most important effect resulting from these fluctuations is the modification of the effective potential in which the Q-ball evolves. This is in addition to spontaneous decay into elementary particle excitations and fission into smaller Q-balls previously considered in the literature, which — like most tunnelling processes — are likely to be strongly suppressed. We illustrate the effect of quantum fluctuations in a particular model ϕ{sup 6} potential, for which we implement the inhomogeneous Hartree approximation to quantum dynamics and solve for the evolution of Q-balls in 3+1 dimensions. We find that the stability range as a function of (field space) angular velocity ω is modified significantly compared to the classical case, so that small-ω Q-balls are less stable than in the classical limit, and large-ω Q-balls are more stable. This can be understood qualitatively in a simple way.

  2. On the quantum stability of Q-balls

    Science.gov (United States)

    Tranberg, Anders; Weir, David J.

    2014-04-01

    We consider the evolution and decay of Q-balls under the influence of quantum fluctuations. We argue that the most important effect resulting from these fluctuations is the modification of the effective potential in which the Q-ball evolves. This is in addition to spontaneous decay into elementary particle excitations and fission into smaller Q-balls previously considered in the literature, which — like most tunnelling processes — are likely to be strongly suppressed. We illustrate the effect of quantum fluctuations in a particular model ϕ 6 potential, for which we implement the inhomogeneous Hartree approximation to quantum dynamics and solve for the evolution of Q-balls in 3 + 1 dimensions. We find that the stability range as a function of (field space) angular velocity ω is modified significantly compared to the classical case, so that small- ω Q-balls are less stable than in the classical limit, and large- ω Q-balls are more stable. This can be understood qualitatively in a simple way.

  3. Future electrical distribution grids: Smart Grids

    International Nuclear Information System (INIS)

    The new energy paradigm faced by distribution network represents a real scientific challenge. Thus, national and EU objectives in terms of environment and energy efficiency with resulted regulatory incentives for renewable energies, the deployment of smart meters and the need to respond to changing needs including new uses related to electric and plug-in hybrid vehicles introduce more complexity and favour the evolution towards a smarter grid. The economic interest group in Grenoble IDEA in connection with the power laboratory G2ELab at Grenoble Institute of technology, EDF and Schneider Electric are conducting research on the electrical distribution of the future in presence of distributed generation for ten years.Thus, several innovations emerged in terms of flexibility and intelligence of the distribution network. One can notice the intelligence solutions for voltage control, the tools of network optimization, the self-healing techniques, the innovative strategies for connecting distributed and intermittent generation or load control possibilities for the distributor. All these innovations are firmly in the context of intelligent networks of tomorrow 'Smart Grids'. (authors)

  4. Efficient Pseudorecursive Evaluation Schemes for Non-adaptive Sparse Grids

    KAUST Repository

    Buse, Gerrit

    2014-01-01

    In this work we propose novel algorithms for storing and evaluating sparse grid functions, operating on regular (not spatially adaptive), yet potentially dimensionally adaptive grid types. Besides regular sparse grids our approach includes truncated grids, both with and without boundary grid points. Similar to the implicit data structures proposed in Feuersänger (Dünngitterverfahren für hochdimensionale elliptische partielle Differntialgleichungen. Diploma Thesis, Institut für Numerische Simulation, Universität Bonn, 2005) and Murarasu et al. (Proceedings of the 16th ACM Symposium on Principles and Practice of Parallel Programming. Cambridge University Press, New York, 2011, pp. 25–34) we also define a bijective mapping from the multi-dimensional space of grid points to a contiguous index, such that the grid data can be stored in a simple array without overhead. Our approach is especially well-suited to exploit all levels of current commodity hardware, including cache-levels and vector extensions. Furthermore, this kind of data structure is extremely attractive for today’s real-time applications, as it gives direct access to the hierarchical structure of the grids, while outperforming other common sparse grid structures (hash maps, etc.) which do not match with modern compute platforms that well. For dimensionality d ≤ 10 we achieve good speedups on a 12 core Intel Westmere-EP NUMA platform compared to the results presented in Murarasu et al. (Proceedings of the International Conference on Computational Science—ICCS 2012. Procedia Computer Science, 2012). As we show, this also holds for the results obtained on Nvidia Fermi GPUs, for which we observe speedups over our own CPU implementation of up to 4.5 when dealing with moderate dimensionality. In high-dimensional settings, in the order of tens to hundreds of dimensions, our sparse grid evaluation kernels on the CPU outperform any other known implementation.

  5. The Computing Grids

    Energy Technology Data Exchange (ETDEWEB)

    Govoni, P. [Universita and INFN Milano-Bicocca (Italy)

    2009-12-15

    Since the beginning of the millennium, High Energy Physics research institutions like CERN and INFN pioneered several projects aimed at exploiting the synergy among computing power, storage and network resources, and creating an infrastructure of distributed computing on a worldwide scale. In the year 2000, after the Monarch project [(http://monarc.web.cern.ch/MONARC/)], DataGrid started [(http://eu-datagrid.web.cern.ch/eu-datagrid/)] aimed at providing High Energy Physics with the computing power needed for the LHC enterprise. This program evolved into the EU DataGrid project, that implemented the first actual prototype of a Grid middleware running on a testbed environment. The next step consisted in the application to the LHC experiments, with the LCG project [(http://lcg.web.cern.ch/LCG/)], in turn followed by the EGEE [(http://www.eu-egee.org/)] and EGEE II programs.

  6. The Computing Grids

    Science.gov (United States)

    Govoni, P.

    2009-12-01

    Since the beginning of the millennium, High Energy Physics research institutions like CERN and INFN pioneered several projects aimed at exploiting the synergy among computing power, storage and network resources, and creating an infrastructure of distributed computing on a worldwide scale. In the year 2000, after the Monarch project [ http://monarc.web.cern.ch/MONARC/], DataGrid started [ http://eu-datagrid.web.cern.ch/eu-datagrid/] aimed at providing High Energy Physics with the computing power needed for the LHC enterprise. This program evolved into the EU DataGrid project, that implemented the first actual prototype of a Grid middleware running on a testbed environment. The next step consisted in the application to the LHC experiments, with the LCG project [ http://lcg.web.cern.ch/LCG/], in turn followed by the EGEE [ http://www.eu-egee.org/] and EGEE II programs.

  7. The Computing Grids

    International Nuclear Information System (INIS)

    Since the beginning of the millennium, High Energy Physics research institutions like CERN and INFN pioneered several projects aimed at exploiting the synergy among computing power, storage and network resources, and creating an infrastructure of distributed computing on a worldwide scale. In the year 2000, after the Monarch project [(http://monarc.web.cern.ch/MONARC/)], DataGrid started [(http://eu-datagrid.web.cern.ch/eu-datagrid/)] aimed at providing High Energy Physics with the computing power needed for the LHC enterprise. This program evolved into the EU DataGrid project, that implemented the first actual prototype of a Grid middleware running on a testbed environment. The next step consisted in the application to the LHC experiments, with the LCG project [(http://lcg.web.cern.ch/LCG/)], in turn followed by the EGEE [(http://www.eu-egee.org/)] and EGEE II programs.

  8. Fusion Data Grid Service

    Science.gov (United States)

    Shasharina, Svetlana; Wang, Nanbor

    2004-11-01

    Simulations and experiments in the fusion and plasma physics community generate large datasets at remote sites. Visualization and analysis of these datasets are difficult because of the incompatibility among the various data formats adopted by simulation, experiments, and analysis tools, and the large sizes of analyzed data. Grids and Web Services technologies are capable of providing solutions for such heterogeneous settings, but need to be customized to the field-specific needs and merged with distributed technologies currently used by the community. This paper describes how we are addressing these issues in the Fusion Grid Service under development. We also present performance results of relevant data transfer mechanisms including binary SOAP, DIME, GridFTP and MDSplus and CORBA. We will describe the status of data converters (between HDF5 and MDSplus data types), developed in collaboration with MIT (J. Stillerman). Finally, we will analyze bottlenecks of MDSplus data transfer mechanism (work performed in collaboration with General Atomics (D. Schissel and M. Qian).

  9. Effect of panel shape of soccer ball on its flight characteristics

    OpenAIRE

    Sungchan Hong; Takeshi Asai

    2014-01-01

    Soccer balls are typically constructed from 32 pentagonal and hexagonal panels. Recently, however, newer balls named Cafusa, Teamgeist 2, and Jabulani were respectively produced from 32, 14, and 8 panels with shapes and designs dramatically different from those of conventional balls. The newest type of ball, named Brazuca, was produced from six panels and will be used in the 2014 FIFA World Cup in Brazil. There have, however, been few studies on the aerodynamic properties of balls constructed...

  10. Smart grid: hope or hype?

    DEFF Research Database (Denmark)

    Lunde, Morten; Røpke, Inge; Heiskanen, Eva

    2016-01-01

    The smart grid is an important but ambiguous element in the future transition of the European energy system. The current paper unpacks one influential national vision of the smart grid to identify what kinds of expectations guide the work of smart grid innovators and how the boundaries of the smart...... how their (intentional or unintentional) choices serve to create or maintain certain boundaries in smart grid development: for example, an exclusive focus on electricity within the broader context of a sustainable energy system. As serious investment starts being made in the smart grid, concepts like...... grid are defined. Building on data from a scenario exercise within a large Danish smart grid project, we examine how the smart grid and the conditions for its realization are defined and delimited. Our findings show that the smart grid hype embodies several implicit expectations that serve to guide...

  11. Process Design of a Ball Joint, Considering Caulking and Pull-Out Strength

    Directory of Open Access Journals (Sweden)

    Bong-Su Sin

    2014-01-01

    Full Text Available A ball joint for an automobile steering system is a pivot component which is connected to knuckle and lower control arm. The manufacturing process for its caulking comprises spinning and deforming. In this study, the process was simulated by flexible multibody dynamics. The caulking was evaluated qualitatively through numerical analysis and inspecting a plastically deformed shape. The structural responses of a ball joint, namely, pull-out strength and stiffness, are commonly investigated in the development process. Thus, following the caulking analysis, the structural responses were considered. In addition, three design variables related to the manufacturing process were defined, and the effects of design variables with respect to pull-out strength, caulking depth, and maximum stress were obtained by introducing the DOE using an L9 orthogonal array. Finally, the optimum design maximizing the pull-out strength was suggested. For the final design, the caulking quality and the pull-out strength were investigated by making six samples and their tests.

  12. Viewpoints on Grid Standards

    Institute of Scientific and Technical Information of China (English)

    Andrew A. Chien; Xian-He Sun; Zhi-Wei Xu

    2005-01-01

    @@ At GCC 2003 in Shanghai in December 2003, a panel discussion was held on the future of grid computing and on the role of the Globus Toolkit in future grid standards. Panelists include Andrew Chien (UCSD, USA), Wolfgang Gentzsch (Sun),Francis Lau (HKU, China), Carl Kesselman (USC, USA), Satoshi Matsuoka (TIT, Japan), Xian-He Sun (IIT, USA), Richard Wirt (Intel), Liang-Jie Zhang (IBM Research), Song-Nian Zhou (Platform Computing), and Zhi-Wei Xu (ICT, China), with Hai Jin (HUST, China) served as the coordinator. The panel talks were stimulating and well received. Three of the panel talk notes are selected and included in this viewpoint.

  13. Distributed photovoltaic grid transformers

    CERN Document Server

    Shertukde, Hemchandra Madhusudan

    2014-01-01

    The demand for alternative energy sources fuels the need for electric power and controls engineers to possess a practical understanding of transformers suitable for solar energy. Meeting that need, Distributed Photovoltaic Grid Transformers begins by explaining the basic theory behind transformers in the solar power arena, and then progresses to describe the development, manufacture, and sale of distributed photovoltaic (PV) grid transformers, which help boost the electric DC voltage (generally at 30 volts) harnessed by a PV panel to a higher level (generally at 115 volts or higher) once it is

  14. Instant jqGrid

    CERN Document Server

    Manricks, Gabriel

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A step-by-step, practical Starter book, Instant jqGrid embraces you while you take your first steps, and introduces you to the content in an easy-to-follow order.This book is aimed at people who have some knowledge of HTML and JavaScript. Knowledge of PHP and SQL would also prove to be beneficial. No prior knowledge of jqGrid is expected.

  15. Grid zone drone

    OpenAIRE

    McCarthy, Clive; Cooper, Graham; Field, James; Thayne, Martyn; Vickers, Richard

    2014-01-01

    From 16th – 19th October 2014, co_LAB presented its newest creation, Grid Zone Drone, at Kinetica – an international exhibition providing a global platform for galleries, curatorial groups, design studios and artists working with new media art. 2014 marked the third consecutive year that the University of Lincoln has been represented at the global art fair. Grid Zone Drone represents a continuation of the group’s research into ‘drone culture’, and explores the detachment of the drone withi...

  16. Grids, Clouds and Virtualization

    CERN Document Server

    Cafaro, Massimo

    2011-01-01

    Research into grid computing has been driven by the need to solve large-scale, increasingly complex problems for scientific applications. Yet the applications of grid computing for business and casual users did not begin to emerge until the development of the concept of cloud computing, fueled by advances in virtualization techniques, coupled with the increased availability of ever-greater Internet bandwidth. The appeal of this new paradigm is mainly based on its simplicity, and the affordable price for seamless access to both computational and storage resources. This timely text/reference int

  17. Phased array antenna matching: Simulation and optimization of a planar phased array of circular waveguide elements

    Science.gov (United States)

    Dudgeon, J. E.

    1972-01-01

    A computerized simulation of a planar phased array of circular waveguide elements is reported using mutual coupling and wide angle impedance matching in phased arrays. Special emphasis is given to circular polarization. The aforementioned computer program has as variable inputs: frequency, polarization, grid geometry, element size, dielectric waveguide fill, dielectric plugs in the waveguide for impedance matching, and dielectric sheets covering the array surface for the purpose of wide angle impedance matching. Parameter combinations are found which produce reflection peaks interior to grating lobes, while dielectric cover sheets are successfully employed to extend the usable scan range of a phased array. The most exciting results came from the application of computer aided optimization techniques to the design of this type of array.

  18. Enabling Campus Grids with Open Science Grid Technology

    Science.gov (United States)

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

    2011-12-01

    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.

  19. Quenching simulation of steel grinding balls

    Directory of Open Access Journals (Sweden)

    Zapata-Hernández, Oscar

    2015-09-01

    Full Text Available The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses.Las transformaciones de fase en aceros de alto carbono durante su temple y un posterior periodo de estabilización fueron modelizadas por medio del uso de paquetes computacionales basados en el método del elemento finito y de la transformación cinética de los aceros. El modelo se usó para predecir los cambios de temperatura y microestructura que se presentan en bolas de dos diferentes tamaños empleadas en estaciones de molienda de minerales. Se encontró una buena correlación entre las temperaturas medidas mediante la inserción de termopares y aquellas predichas por el modelo una vez que se modificó la conductividad térmica del acero en el intervalo mixto de fases. La predicción de las transformaciones de fase se confirmó a través del análisis metalográfico.

  20. Theory of operation for the ball rheometer

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, C.L.; Colson, J.B. [Pacific Northwest Lab., Richland, WA (United States); Pasamehmetoglu, K.O.; Unal, C.; Edwards, J.N.; Abbott, J. [Los Alamos National Lab., NM (United States)

    1994-12-01

    The Hanford Site contains over 100 high-volume tanks containing high-level radioactive wastes. The tank which has received the most attention is Tank 101-SY, which is a double shell tank containing a caustic mixed-waste slurry. The ball rheometer developed in this work is intended at least initially for application in this tank. Tank 101-SY is known to periodically release flammable and toxic gases during events known as rollovers. The tank waste is largely made up of two layers, a supernatant liquid layer underneath which is a thick sludge layer. The two layers are called the convective (C) and the nonconvective (NC) regions, so called because of the thermal transport properties ascribed to each. Although they have significant uncertainty, the current theology data suggest the existence of a yield stress in the highly viscous nonconvective layer. Gas generated in the waste can be held in the NC layer if the material yield strength or its viscosity is high enough. Gas cannot be held in the C layer to any appreciable extent unless it is in solution. As gas continues to be generated by chemical or other processes, the number of gas bubbles and/or their sizes increases in the NC layer. A rollover occurs when the amount of gas trapped in the nonconvective region becomes great enough to overcome forces holding it in place. These forces are believed to be dependent on the theology of the nonconvective region and perhaps the bubble surface tension. The buoyancy forces on the bubbles exceed the restraining forces arising from the yield stress and the viscosity of the NC layer. Theology is then seen to be quite important in determining the nature of gas release events in this tank.

  1. THE BEHAVIOURAL REACTION OF WEANERS TO HANGING TOYS: WOODEN BALL AND AROMATIZED WOODEN BALL – WAY TO REDUCE AGGRESSION AFTER MIXING

    Directory of Open Access Journals (Sweden)

    Jacek NOWICKI

    2008-05-01

    Full Text Available The behaviour of weaners after mixing housed in pens equipped with hanging wooden ball, aromatized with vanilla fluid hanging wooden ball and without enrichment was evaluated. It was found that both enrichments reduced aggression, however the most interesting for weaners was the aromatized wooden ball.

  2. Receiver architecture of the thousand-element array (THEA)

    OpenAIRE

    Kant, G. W.; Kokkeler, A. B. J.; Smolders, A.B.; Gunst, A. W.

    2000-01-01

    As part of the development of a new international radio-telescope SKA (Square Kilometre Array), an outdoor phasedarray prototype, the THousand Element Array (THEA), is being developed at NFRA. THEA is a phased array with 1024 active elements distributed on a regular grid over a surface of approximately 16 m2. The array is organised into 16 units denoted as tiles. THEA operates in the frequency band from 750 to 1500 MHz. On a tile the signals from 64 antenna elements are converted into two ind...

  3. Modelling Chinese Smart Grid

    DEFF Research Database (Denmark)

    Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming;

    In this document, we consider a specific Chinese Smart Grid implementation and try to address the verification problem for certain quantitative properties including performance and battery consumption. We employ stochastic model checking approach and present our modelling and analysis study using...

  4. PPARC delivering the Grid

    CERN Multimedia

    2003-01-01

    "PPARC scientists are helping to deliver the Grid, the next generation of internet infrastructure. On September 2-4th, they will be presenting their progress at the UK's All Hands E-Science meeting in Nottingham, the forum for all UK scientists in this research area" (1 page).

  5. NSTAR Smart Grid Pilot

    Energy Technology Data Exchange (ETDEWEB)

    Rabari, Anil [NSTAR Electric, Manchester, NH (United States); Fadipe, Oloruntomi [NSTAR Electric, Manchester, NH (United States)

    2014-03-31

    NSTAR Electric & Gas Corporation (“the Company”, or “NSTAR”) developed and implemented a Smart Grid pilot program beginning in 2010 to demonstrate the viability of leveraging existing automated meter reading (“AMR”) deployments to provide much of the Smart Grid functionality of advanced metering infrastructure (“AMI”), but without the large capital investment that AMI rollouts typically entail. In particular, a central objective of the Smart Energy Pilot was to enable residential dynamic pricing (time-of-use “TOU” and critical peak rates and rebates) and two-way direct load control (“DLC”) by continually capturing AMR meter data transmissions and communicating through customer-sited broadband connections in conjunction with a standardsbased home area network (“HAN”). The pilot was supported by the U.S. Department of Energy’s (“DOE”) through the Smart Grid Demonstration program. NSTAR was very pleased to not only receive the funding support from DOE, but the guidance and support of the DOE throughout the pilot. NSTAR is also pleased to report to the DOE that it was able to execute and deliver a successful pilot on time and on budget. NSTAR looks for future opportunities to work with the DOE and others in future smart grid projects.

  6. Minnesota Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1.5 kilometer Bouguer anomaly grid for the state of Minnesota. Number of columns is 404 and number of rows is 463. The order of the data is from the lower left to...

  7. Bolivian Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Bouguer anomaly grid for the country of Bolivia.Number of columns is 550 and number of rows is 900. The order of the data is from the lower left to...

  8. Steering the Smart Grid

    NARCIS (Netherlands)

    Molderink, Albert; Bakker, Vincent; Bosman, Maurice G.C.; Hurink, Johann L.; Smit, Gerard J.M.

    2010-01-01

    Increasing energy prices and the greenhouse effect lead to more awareness of energy efficiency of electricity supply. During the last years, a lot of technologies and optimization methodologies were developed to increase the efficiency, maintain the grid stability and support large scale introductio

  9. Nevada Bouguer Gravity Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 2 kilometer Bouguer anomaly grid for the state of Nevada. Number of columns is 282 and number of rows is 397. The order of the data is from the lower left to the...

  10. Kids Enjoy Grids

    CERN Document Server

    2007-01-01

    I want to come back and work here when I'm older,' was the spontaneous reaction of one of the children invited to CERN by the Enabling Grids for E-sciencE project for a 'Grids for Kids' day at the end of January. The EGEE project is led by CERN, and the EGEE gender action team organized the day to introduce children to grid technology at an early age. The school group included both boys and girls, aged 9 to 11. All of the presenters were women. 'In general, before this visit, the children thought that scientists always wore white coats and were usually male, with wild Einstein-like hair,' said Jackie Beaver, the class's teacher at the Institut International de Lancy, a school near Geneva. 'They were surprised and pleased to see that women became scientists, and that scientists were quite 'normal'.' The half-day event included presentations about why Grids are needed, a visit of the computer centre, some online games, and plenty of time for questions. In the end, everyone agreed that it was a big success a...

  11. Maine Bouguer Gravity Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 2 kilometer Bouguer anomaly grid for the state of Maine. Number of columns is 197 and number of rows is 292. The order of the data is from the lower left to the...

  12. The Grid challenge

    CERN Multimedia

    Lundquest, E

    2003-01-01

    At a customer panel discussion during OracleWorld in San Franciso, grid computing was being pushed as the next big thing - even if panellists couldsn't quite agree on what it is, what it will cost or when it will appear (1 page).

  13. Grid attacks avian flu

    CERN Multimedia

    2006-01-01

    During April, a collaboration of Asian and European laboratories analysed 300,000 possible drug components against the avian flu virus H5N1 using the EGEE Grid infrastructure. Schematic presentation of the avian flu virus.The distribution of the EGEE sites in the world on which the avian flu scan was performed. The goal was to find potential compounds that can inhibit the activities of an enzyme on the surface of the influenza virus, the so-called neuraminidase, subtype N1. Using the Grid to identify the most promising leads for biological tests could speed up the development process for drugs against the influenza virus. Co-ordinated by CERN and funded by the European Commission, the EGEE project (Enabling Grids for E-sciencE) aims to set up a worldwide grid infrastructure for science. The challenge of the in silico drug discovery application is to identify those molecules which can dock on the active sites of the virus in order to inhibit its action. To study the impact of small scale mutations on drug r...

  14. Development of a new spacer grid form to enhance the integrity of fuel rod support and the crush strength of a spacer grid assembly

    International Nuclear Information System (INIS)

    A spacer grid is one of the most important structural components in a PWR fuel assembly. The spacer grid, which supports nuclear fuel rods laterally and vertically with a friction grip, is an interconnected array of slotted grid straps welded at the intersections to form an egg crate structure. Dimples and springs are stamped into each grid strap to support the fuel rods. The form of grid straps and spring form is known to be closely related with the crush strength of spacer grid assembly and the integrity of fuel rod support, respectively. Zircaloy is prevailing as the material of the spacer grid because of its low neutron absorption characteristic and its successful extensive in reactor use. The primary considerations are to provide a Zircaloy spacer grid with crush strength sufficient to resist design basis loads, without significantly increasing pressure drop across the reactor core. Generally, the thickness and height of the Zircaloy grid strap have been the main design variables in order to meet the above considerations. Recently, it was reported that a dimple location is also a design variable that affects the crush strength of a spacer grid. In this study, a new spacer grid form was developed in order to enhance the integrity of the fuel rod support and the crush strength of the spacer grid assembly by using a systematic optimization technique. The enhancement of fuel rod support was confirmed by comparisons of contact area, peak stresses, plastic deformation and etc. while the enhancement of crush strength was investigated for a 3x3 and 7x7 sub size support grid as a preliminary parameter study for a 16x16 full size support grid. The 3x3 model is chosen to facilitate quick computation for optimization and the 7x7 model is chosen to verify the enhancement

  15. Control of a grid connected converter during weak grid conditions

    DEFF Research Database (Denmark)

    Lorenzen, Søren Lund; Nielsen, Alex Buus; Bede, L.

    2016-01-01

    the case for offshore wind turbines. This can cause the wind farm grid networks to be weak. A weak network is an extra challenge to inject energy into, since it might exceed grid codes and grid standard values, if not compensated for. To ensure quality of the energy injected to the network, a Voltage...

  16. Implementation of Computational Grid Services in Enterprise Grid Environments

    Directory of Open Access Journals (Sweden)

    R. J.A. Richard

    2008-01-01

    Full Text Available Grid Computing refers to the development of high performance computing environment or virtual super computing environment by utilizing available computing resources in a LAN, WAN and Internet. This new emerging research field offers enormous opportunities for e-Science applications such as astrophysics, bioinformatics, aerospace modeling, cancer research etc. Grid involves coordinating and sharing of computing power, application, data storage, network resources etc., across dynamically and geographically dispersed organizations. Most Grid environments are developed using Globus toolkit which is a UNIX/Linux based middleware to integrate computational resources over the network. The emergence of Global Grid concept provides an excellent opportunity for Grid based e-Science applications to use high performance super computing environments. Thus windows based enterprise grid environments can't be neglected in the development of Global Grids. This study discusses the basics of enterprise grids and the implementation of enterprise computational grids using Alchemi Tool Kit. This review study is organized into three parts. They are (i Introduction of Grid Technologies, (ii Design Concepts of Enterprise Grids and (iii Implementation of Computational Grid Services.

  17. Allegheny County Map Index Grid

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Map Index Sheets from Block and Lot Grid of Property Assessment and based on aerial photography, showing 1983 datum with solid line and NAD 27 with 5 second grid...

  18. HIRENASD Unstructured Grids - Centaur software

    Data.gov (United States)

    National Aeronautics and Space Administration — These grids were constructed using Centaur software at DLR in Germany. The grids designed for node based (labeled 'cv') and cell-centered solvers (labeled 'cc') are...

  19. Grid Concept in Business Application

    OpenAIRE

    Timofte Carmen

    2011-01-01

    Grid is a centerpiece of the "utility computing" marketing drive taken up by nearly every vendor. Load balancers, clustering solutions, blade servers—just about any product can come to market with a grid label. The grid technologies, like smart grid, and services will help companies to be winners in the acerb competition. This paper presents an overview of grid’s technologies, services and application and try to preview the direction’s trend.

  20. An Off-Grid Turbo Channel Estimation Algorithm for Millimeter Wave Communications

    Directory of Open Access Journals (Sweden)

    Lingyi Han

    2016-09-01

    Full Text Available The bandwidth shortage has motivated the exploration of the millimeter wave (mmWave frequency spectrum for future communication networks. To compensate for the severe propagation attenuation in the mmWave band, massive antenna arrays can be adopted at both the transmitter and receiver to provide large array gains via directional beamforming. To achieve such array gains, channel estimation (CE with high resolution and low latency is of great importance for mmWave communications. However, classic super-resolution subspace CE methods such as multiple signal classification (MUSIC and estimation of signal parameters via rotation invariant technique (ESPRIT cannot be applied here due to RF chain constraints. In this paper, an enhanced CE algorithm is developed for the off-grid problem when quantizing the angles of mmWave channel in the spatial domain where off-grid problem refers to the scenario that angles do not lie on the quantization grids with high probability, and it results in power leakage and severe reduction of the CE performance. A new model is first proposed to formulate the off-grid problem. The new model divides the continuously-distributed angle into a quantized discrete grid part, referred to as the integral grid angle, and an offset part, termed fractional off-grid angle. Accordingly, an iterative off-grid turbo CE (IOTCE algorithm is proposed to renew and upgrade the CE between the integral grid part and the fractional off-grid part under the Turbo principle. By fully exploiting the sparse structure of mmWave channels, the integral grid part is estimated by a soft-decoding based compressed sensing (CS method called improved turbo compressed channel sensing (ITCCS. It iteratively updates the soft information between the linear minimum mean square error (LMMSE estimator and the sparsity combiner. Monte Carlo simulations are presented to evaluate the performance of the proposed method, and the results show that it enhances the angle

  1. An Off-Grid Turbo Channel Estimation Algorithm for Millimeter Wave Communications.

    Science.gov (United States)

    Han, Lingyi; Peng, Yuexing; Wang, Peng; Li, Yonghui

    2016-09-22

    The bandwidth shortage has motivated the exploration of the millimeter wave (mmWave) frequency spectrum for future communication networks. To compensate for the severe propagation attenuation in the mmWave band, massive antenna arrays can be adopted at both the transmitter and receiver to provide large array gains via directional beamforming. To achieve such array gains, channel estimation (CE) with high resolution and low latency is of great importance for mmWave communications. However, classic super-resolution subspace CE methods such as multiple signal classification (MUSIC) and estimation of signal parameters via rotation invariant technique (ESPRIT) cannot be applied here due to RF chain constraints. In this paper, an enhanced CE algorithm is developed for the off-grid problem when quantizing the angles of mmWave channel in the spatial domain where off-grid problem refers to the scenario that angles do not lie on the quantization grids with high probability, and it results in power leakage and severe reduction of the CE performance. A new model is first proposed to formulate the off-grid problem. The new model divides the continuously-distributed angle into a quantized discrete grid part, referred to as the integral grid angle, and an offset part, termed fractional off-grid angle. Accordingly, an iterative off-grid turbo CE (IOTCE) algorithm is proposed to renew and upgrade the CE between the integral grid part and the fractional off-grid part under the Turbo principle. By fully exploiting the sparse structure of mmWave channels, the integral grid part is estimated by a soft-decoding based compressed sensing (CS) method called improved turbo compressed channel sensing (ITCCS). It iteratively updates the soft information between the linear minimum mean square error (LMMSE) estimator and the sparsity combiner. Monte Carlo simulations are presented to evaluate the performance of the proposed method, and the results show that it enhances the angle detection

  2. JColorGrid: software for the visualization of biological measurements

    Directory of Open Access Journals (Sweden)

    May Barnaby CH

    2006-04-01

    Full Text Available Abstract Background Two-dimensional data colourings are an effective medium by which to represent three-dimensional data in two dimensions. Such "color-grid" representations have found increasing use in the biological sciences (e.g. microarray 'heat maps' and bioactivity data as they are particularly suited to complex data sets and offer an alternative to the graphical representations included in traditional statistical software packages. The effectiveness of color-grids lies in their graphical design, which introduces a standard for customizable data representation. Currently, software applications capable of generating limited color-grid representations can be found only in advanced statistical packages or custom programs (e.g. micro-array analysis tools, often associated with steep learning curves and requiring expert knowledge. Results Here we describe JColorGrid, a Java library and platform independent application that renders color-grid graphics from data. The software can be used as a Java library, as a command-line application, and as a color-grid parameter interface and graphical viewer application. Data, titles, and data labels are input as tab-delimited text files or Microsoft Excel spreadsheets and the color-grid settings are specified through the graphical interface or a text configuration file. JColorGrid allows both user graphical data exploration as well as a means of automatically rendering color-grids from data as part of research pipelines. Conclusion The program has been tested on Windows, Mac, and Linux operating systems, and the binary executables and source files are available for download at http://jcolorgrid.ucsf.edu.

  3. Grid3: An Application Grid Laboratory for Science

    CERN Document Server

    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...

  4. Grid Interaction Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The mission of the Grid Interaction Technical Team (GITT) is to support a transition scenario to large scale grid-connected vehicle charging with transformational technology, proof of concept and information dissemination. The GITT facilitates technical coordination and collaboration between vehicle-grid connectivity and communication activities among U.S. DRIVE government and industry partners.

  5. Smart grids put into practice

    NARCIS (Netherlands)

    Veldman, E.; Geldtmeijer, D.A.M.; Slootweg, J.G.

    2009-01-01

    The transition towards a more sustainable energ y supply system causes changes in the supply and demand of energ y. It requires a more flexible and efficient operation of the electricity distribution grids. It calls for a smart grid with intelligent control embedded in the grids to incorporate elect

  6. New data on the formation of Carboniferous coal balls

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A.C.; Mattey, D.P.; Howard, R. [University of London, Egham (United Kingdom). Royal Holloway and Bedford New College, Dept. of Geology

    1996-10-01

    Coal balls are formed from the precipitation of carbonate minerals, predominantly calcite, from water during or immediately post-peat formation. Previous petrological studies suggest permineralization occurred at various stages during the peatificiation process by precipitation from a mixture of marine and meteoric freshwater. The geochemical studies reported here aimed to test previous theories of coal ball formation. The coal balls studied are from Upper Carboniferous and Carboniferous/Permian coal seams in Britain, United States of America, Belgium and China. Stable carbon isotopic values of calcites range from {delta}{sup 13}C of -5 to -35 parts per thousand indicating highly variable contribution of decayed organic matter to the carbonate cement. Oxygen isotopic values of delta({sup 18}) range from -3 to -15 parts per thousand suggest both marine and meteoric freshwater sources. The range, in the British coal balls in particular, with {delta}{sup 13}C ranging from -7 to -25 parts per thousand indicates the complexity of carbonate generation. Isotopic data support at least four theories of carbonate coal ball formation. This makes their absence from post-Permian coals the more puzzling and it is suggested that the overall structure of the peat may play a role.

  7. Contribution to the physics of high energy ball milling

    International Nuclear Information System (INIS)

    We have characterized the parameters which control the stability of amorphous phases under ball milling on the model alloys (NixZry). We have improved a vibrating frame grinder to perform experiments at several controlled temperatures under static vacuum. Based on analyzing the movement of the milling ball, we have evaluated the frequency of impact (f) and the relative velocity of the ball at the time impact (Vmax) for different vibration amplitudes of the frame. The kinetic of amorphization by ball milling, studied by x-ray diffraction and transmission electron microscopy, shows that: - a fully amorphous phase is obtained provided that the 'specific milling intensity' is larger than a threshold value. The specific milling intensity is defined as the impact momentum times the impact frequency divided by the mass of powder (MbVmaxf/Mp): Mp, Mb are the mass of the ball and the powder). The threshold is composition and temperature dependent; - below the amorphization threshold, a two-phase microstructure (crystalline phase imbedded in an amorphous cement) is stabilized. The alloy achieves a steady state fraction of amorphous phase, which increases with the milling intensity and decreases with increasing the milling temperature. A study of the mechanical alloying of NbTiAl2 starting from elemental powders is also presented. (Author). refs., figs., tabs

  8. Suppressing Heavy Metal Leaching through Ball Milling of Fly Ash

    Directory of Open Access Journals (Sweden)

    Zhiliang Chen

    2016-07-01

    Full Text Available Ball milling is investigated as a method of reducing the leaching concentration (often termed stablilization of heavy metals in municipal solid waste incineration (MSWI fly ash. Three heavy metals (Cu, Cr, Pb loose much of their solubility in leachate by treating fly ash in a planetary ball mill, in which collisions between balls and fly ash drive various physical processes, as well as chemical reactions. The efficiency of stabilization is evaluated by analysing heavy metals in the leachable fraction from treated fly ash. Ball milling reduces the leaching concentration of Cu, Cr, and Pb, and water washing effectively promotes stabilization efficiency by removing soluble salts. Size distribution and morphology of particles were analysed by laser particle diameter analysis and scanning electron microscopy. X-ray diffraction analysis reveals significant reduction of the crystallinity of fly ash by milling. Fly ash particles can be activated through this ball milling, leading to a significant decrease in particle size, a rise in its BET-surface, and turning basic crystals therein into amorphous structures. The dissolution rate of acid buffering materials present in activated particles is enhanced, resulting in a rising pH value of the leachate, reducing the leaching out of some heavy metals.

  9. Kicking velocity and effect on match performance when using a smaller, lighter ball in women's football

    DEFF Research Database (Denmark)

    Andersen, Thomas B.; Krustrup, Peter; Bendiksen, Mads;

    2016-01-01

    The present study evaluated the effect of a smaller, lighter ball on kicking speed and technical-tactical and physical match performance in high-level adult female footballers. In the laboratory test setting, the peak ball velocity was 6% higher with the new ball (NB) than the standard ball (SB...... in passing success rate (NB: 68±1% and SB: 68±1%, p>0.05). In conclusion, high-level adult female footballers had a higher kicking speed when using a smaller, lighter ball, but no differences were observed during match-play with the 2 ball types in respect of technical-tactical and physical match...

  10. Effects of turbulence on the drag force on a golf ball

    Science.gov (United States)

    Cross, Rod

    2016-09-01

    Measurements are presented of the drag force on a golf ball dropped vertically into a tank of water. As observed previously in air, the drag coefficient drops sharply when the flow becomes turbulent. The experiment would be suitable for undergraduate students since it can be undertaken at low ball speeds and since the effects of turbulence are easily observed on video film. A modified golf ball was used to show how a ball with a smooth and a rough side, such as a cricket ball, is subject to a side force when the ball surface itself is asymmetrical in the transverse direction.

  11. Smart Grid Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Craig [National Rural Electric Cooperative Association, Arlington, VA (United States); Carroll, Paul [National Rural Electric Cooperative Association, Arlington, VA (United States); Bell, Abigail [National Rural Electric Cooperative Association, Arlington, VA (United States)

    2015-03-11

    The National Rural Electric Cooperative Association (NRECA) organized the NRECA-U.S. Department of Energy (DOE) Smart Grid Demonstration Project (DE-OE0000222) to install and study a broad range of advanced smart grid technologies in a demonstration that spanned 23 electric cooperatives in 12 states. More than 205,444 pieces of electronic equipment and more than 100,000 minor items (bracket, labels, mounting hardware, fiber optic cable, etc.) were installed to upgrade and enhance the efficiency, reliability, and resiliency of the power networks at the participating co-ops. The objective of this project was to build a path for other electric utilities, and particularly electrical cooperatives, to adopt emerging smart grid technology when it can improve utility operations, thus advancing the co-ops’ familiarity and comfort with such technology. Specifically, the project executed multiple subprojects employing a range of emerging smart grid technologies to test their cost-effectiveness and, where the technology demonstrated value, provided case studies that will enable other electric utilities—particularly electric cooperatives— to use these technologies. NRECA structured the project according to the following three areas: Demonstration of smart grid technology; Advancement of standards to enable the interoperability of components; and Improvement of grid cyber security. We termed these three areas Technology Deployment Study, Interoperability, and Cyber Security. Although the deployment of technology and studying the demonstration projects at coops accounted for the largest portion of the project budget by far, we see our accomplishments in each of the areas as critical to advancing the smart grid. All project deliverables have been published. Technology Deployment Study: The deliverable was a set of 11 single-topic technical reports in areas related to the listed technologies. Each of these reports has already been submitted to DOE, distributed to co-ops, and

  12. Design of a high precision falling-ball viscometer

    International Nuclear Information System (INIS)

    The increase in uncertainty throughout the viscosity scale being the principal disadvantage of capillary viscometry, an absolute falling-ball viscometer has been developed, making it possible to cover a wide range of viscosities while keeping a weak uncertainty. The measurement of viscosity of a liquid then rests on the terminal velocity measurement of a falling ball, corrected by the principal identified effects (edge effects, inertial effects, etc.). An experimental bench was developed in order to reach a relative uncertainty of the order of 10-3 to the measure of viscosity. The bench, by the use of a linear camera, allows us to observe the trajectory and to obtain the variations in velocity of the ball inside a cylindrical tube filled with liquid whose viscosity is to be measured

  13. Realtime Vision-Based Surface Defect Inspection of Steel Balls

    Institute of Scientific and Technical Information of China (English)

    Wang Zhong; Xing Qian; Fu Luhua; Sun Hong

    2015-01-01

    In the proposed system for online inspection of steel balls, a diffuse illumination is developed to enhance defect appearances and produce high quality images. To fully view the entire sphere, a novel unfolding method is put forward based on geometrical analysis, which only requires one-dimensional movement of the balls and a pair of cam-eras to capture images from different directions. Moreover, a realtime inspection algorithm is customized to improve both accuracy and efficiency. The precision and recall of the sample set were 87.7% and 98%, respectively. The aver-age time cost on image processing and analysis for a steel ballwas 47 ms, and the total time cost was less than 200 ms plus the cost of image acquisition and balls’ movement. The system can sort 18 000 balls per hour with a spatial reso-lution higher than 0.01 mm.

  14. Modeling golf ball fluid mechanics - challenges and opportunities

    Science.gov (United States)

    Squires, Kyle

    2009-11-01

    Numerical simulation presents a powerful tool for understanding the fundamental fluid mechanics that influence golf ball aerodynamics, as well as providing an approach for ultimately analyzing and designing golf balls for manufacture. Robust and accurate simulation strategies are central to providing a means to screen designs prior to costly prototyping and field measurement. Results from a hierarchy of simulation strategies applied to the flow around golf balls will be presented, ranging from Reynolds-averaged Navier-Stokes (RANS) computations to Direct Numerical Simulation (DNS). RANS methods, while leading to computationally efficient approaches, are challenged to represent using ad hoc turbulence models the subtle effects induced by surface dimpling. DNS on the other hand, offers a first-principles approach that enables detailed examination of mechanisms though carries a significant computational cost. Predictions from both techniques are contrasted; opportunities for advancing each technique are identified.

  15. Propagating $q$-field and $q$-ball solution

    CERN Document Server

    Klinkhamer, F R

    2016-01-01

    One possible solution of the cosmological constant problem involves a so-called $q$-field, which self-adjusts so as to give a vanishing gravitating vacuum energy density (cosmological constant) in equilibrium. We show that this $q$-field can manifest itself in other ways. Specifically, we establish a propagating mode ($q$-wave) in the nontrivial vacuum and find a particular soliton-type solution in flat spacetime, which we call a $q$-ball by analogy with the well-known $Q$-ball solution. Both $q$-waves and $q$-balls are expected to play a role for the equilibration of the $q$-field in the very early universe.

  16. On the 1-density of Unit Ball Covering

    CERN Document Server

    Zhu, Binhai

    2007-01-01

    Motivated by modern applications like image processing and wireless sensor networks, we consider a variation of the famous Kepler Conjecture. Given any infinite set of unit balls covering the whole space, we want to know the optimal (lim sup) density of the volume which is covered by exactly one ball (i.e., the maximum such density over all unit ball covers, called the {\\em optimal 1-density} and denoted as $\\delta_d$, where $d$ is the dimension of the Euclidean space). We prove that in 2D the optimal 1-density $\\delta_2=(3\\sqrt(3)-\\pi)/\\pi \\approx 0.6538$, which is achieved through a hexagonal covering. In 3D, we show numerically that the dodecahedral covering ({\\em dc}) achieves a 1-density $\\delta_3(dc)\\approx 0.315$. We conjecture that this is in fact the optimal 1-density in 3D.

  17. The Heads and Tails of Buoyant Autocatalytic Balls

    CERN Document Server

    Rogers, Michael C

    2012-01-01

    Buoyancy produced by autocatalytic reaction fronts can produce fluid flows that advect the front position, giving rise to interesting feedback between chemical and hydrodynamic effects. In a large diameter, extended cylinder that is relatively free of boundary constraints, localized initiation of an iodate-arsenous acid (IAA) reaction front on the bottom boundary generates a rising autocatalytic plume. Such plumes have several differences from their non-reactive counterparts. Using numerical simulation, we have found that if reaction is initiated using a spherical ball of product solution well above the bottom boundary, the subsequent flow can evolve much like an autocatalytic plume: the ball develops a reacting head and tail that is akin to the head and conduit of an autocatalytic plume, except that the tail is disconnected from the boundary. In the limit of large initial autocatalytic balls, however, growth of a reacting tail is suppressed and the resemblance to plumes disappears. Conversely, very small bal...

  18. Supermassive dark-matter Q-balls in galactic centers?

    CERN Document Server

    Troitsky, Sergey

    2015-01-01

    Though widely accepted, it is not proven that supermassive compact objects (SMCOs) residing in galactic centers are black holes. In particular, the Milky Way's SMCO can be a giant nontopological soliton, Q-ball, made of a scalar field: this fits perfectly all observational data. Similar but tiny Q-balls produced in the early Universe may constitute, partly or fully, the dark matter. This picture explains in a natural way, why our SMCO has very low accretion rate and why the observed angular size of the corresponding radio source is much smaller than expected. Interactions between dark-matter Q-balls may explain how SMCOs were seeded in galaxies and resolve well-known problems of standard (non-interacting) dark matter.

  19. Mixing vane grid spacer

    International Nuclear Information System (INIS)

    A spacer for a nuclear fuel reactor grid is described having intersecting spring retaining strips for forming fuel element receiving openings and mixing vanes formed at selected ones of the intersections of the strips. The vanes are angularly disposed relative to the strips and overlie predetermined openings at the intersections; each has an opening located above the intersection for improving its coolant flow mixing capability

  20. Steering the Smart Grid

    OpenAIRE

    Molderink, Albert; Bakker, Vincent; Bosman, Maurice G.C.; Hurink, Johann L.; Smit, Gerard J.M.

    2010-01-01

    Increasing energy prices and the greenhouse effect lead to more awareness of energy efficiency of electricity supply. During the last years, a lot of technologies and optimization methodologies were developed to increase the efficiency, maintain the grid stability and support large scale introduction of renewable sources. In previous work, we showed the effectiveness of our three-step methodology to reach these objectives, consisting of 1) offline prediction, 2) offline planning and 3) online...

  1. TRMM Gridded Text Products

    Science.gov (United States)

    Stocker, Erich Franz

    2007-01-01

    NASA's Tropical Rainfall Measuring Mission (TRMM) has many products that contain instantaneous or gridded rain rates often among many other parameters. However, these products because of their completeness can often seem intimidating to users just desiring surface rain rates. For example one of the gridded monthly products contains well over 200 parameters. It is clear that if only rain rates are desired, this many parameters might prove intimidating. In addition, for many good reasons these products are archived and currently distributed in HDF format. This also can be an inhibiting factor in using TRMM rain rates. To provide a simple format and isolate just the rain rates from the many other parameters, the TRMM product created a series of gridded products in ASCII text format. This paper describes the various text rain rate products produced. It provides detailed information about parameters and how they are calculated. It also gives detailed format information. These products are used in a number of applications with the TRMM processing system. The products are produced from the swath instantaneous rain rates and contain information from the three major TRMM instruments: radar, radiometer, and combined. They are simple to use, human readable, and small for downloading.

  2. 3D Structured Grid Adaptation

    Science.gov (United States)

    Banks, D. W.; Hafez, M. M.

    1996-01-01

    Grid adaptation for structured meshes is the art of using information from an existing, but poorly resolved, solution to automatically redistribute the grid points in such a way as to improve the resolution in regions of high error, and thus the quality of the solution. This involves: (1) generate a grid vis some standard algorithm, (2) calculate a solution on this grid, (3) adapt the grid to this solution, (4) recalculate the solution on this adapted grid, and (5) repeat steps 3 and 4 to satisfaction. Steps 3 and 4 can be repeated until some 'optimal' grid is converged to but typically this is not worth the effort and just two or three repeat calculations are necessary. They also may be repeated every 5-10 time steps for unsteady calculations.

  3. 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

  4. Note: A 1-m Foucault pendulum rolling on a ball

    Science.gov (United States)

    Salva, H. R.; Benavides, R. E.; Venturino, J. A.; Cuscueta, D. J.; Ghilarducci, A. A.

    2013-10-01

    We have built a short Foucault pendulum of 1-m length. The aim of this work was to increase the sensitivity to elliptical trajectories from other longer pendula. The design was a semi-rigid pendulum that rolls over a small ball. The measurements of the movements (azimuth and elliptical trajectory) were done by an optical method. The resulting pendulum works in a medium satisfactory way due to problems of the correct choice of the mass of the bob together with the diameter of the supporting ball. It is also important to keep the rolling surface very clean.

  5. Comparison of exit time moment spectra for extrinsic metric balls

    DEFF Research Database (Denmark)

    Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente

    We prove explicit upper and lower bounds for the $L^1$-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds $P^m$ in ambient Riemannian spaces $N^{n}$. We assume that $P$ and $N$ both have controlled radial curvatures (mean curvature and sectional curvature......, respectively) as viewed from a pole in $N$. The bounds for the exit moment spectra are given in terms of the corresponding spectra for geodesic metric balls in suitably warped product model spaces. The bounds are sharp in the sense that equalities are obtained in characteristic cases. As a corollary we also...

  6. Ball Lens Fiber Optic Sensor based Smart Handheld Microsurgical Instrument

    Science.gov (United States)

    Song, Cheol; Gehlbach, Peter L.; Kang, Jin U.

    2013-01-01

    During freehand performance of vitreoretinal microsurgery the surgeon must perform precise and stable maneuvers that achieve surgical objectives and avoid surgical risk. Here, we present an improved smart handheld microsurgical tool which is based on a ball lens fiber optic sensor that utilizes common path swept source optical coherence tomography. Improvements include incorporation of a ball lens single mode fiber optic probe that increases the working angle of the tool to greater than 45 degrees; and increases the magnitude of the distance sensing signal through water. Also presented is a cutting function with an improved ergonomic design. PMID:24224076

  7. Proposal of a dual-ball atomic fountain clock

    Institute of Scientific and Technical Information of China (English)

    Chunyan Shi; Rong Wei; Zichao Zhou; Tang Li; Yuzhu Wang

    2011-01-01

    @@ A simple improved structure is designed to trap and launch two cold atomic balls vertically at the same time, which works like "two fountains", but is more compact since most components of the "two fountains"are shared.It is expected to improve the stability of the fountain markedly.%A simple improved structure is designed to trap and launch two cold atomic balls vertically at the same time, which works like “two fountains”, but is more compact since most components of the “two fountains”are shared. It is expected to improve the stability of the fountain markedly.

  8. Energy Landscape of d-Dimensional Q-balls

    CERN Document Server

    Gleiser, M; Gleiser, Marcelo; Thorarinson, Joel

    2005-01-01

    We investigate the properties of Q-balls in d spatial dimensions. First, a generalized virial relation for these objects is obtained, followed by variational estimates for their energies for arbitrary charge Q. These analytical estimates are then contrasted with numerical results and their accuracy evaluated. Based on the results, we offer a simple criterion to classify ``large'' and ``small'' d-dimensional Q-balls. A minimum charge is computed and its dependence on spatial dimensionality is shown to scale as \\Q_{\\rm min} \\sim \\exp(d). We also briefly investigate the existence of Q-clouds in d dimensions.

  9. A power recirculating test rig for ball screw endurance tests

    Directory of Open Access Journals (Sweden)

    Giberti Hermes

    2016-01-01

    Full Text Available A conceptual design of an innovative test rig for endurance tests of ball screws is presented in this paper. The test rig layout is based on the power recirculating principle and it also allows to overtake the main critical issues of the ball screw endurance tests. Among these there are the high power required to make the test, the lengthy duration of the same and the high loads between the screw and the frame that holds it. The article describes the test rig designed scheme, the kinematic expedients to be adopted in order to obtain the required performance and functionality and the sizing procedure to choose the actuation system.

  10. Boric Acid Levels in Fresh Noodles and Fish Ball

    OpenAIRE

    Pang-Hung Yiu; Jian See; Amartalingam Rajan; Choon-Fah J. Bong

    2008-01-01

    Boric acid (H3BO3) is detrimental to human health if consumed in excess. However, it continues to be used in the production of food especially noodles and some processed seafood such as fish ball. Five kinds of noodles and a type of fish ball were collected over a period of four weeks from a random sample of manufacturers in Bintulu, Sarawak, Malaysia. The boric acid in these food samples were analyzed by the curcumin-acetic acid method using 2-ethyl-1, 3-hexanediol (EHD) extraction. Results ...

  11. GridTool: A surface modeling and grid generation tool

    Science.gov (United States)

    Samareh-Abolhassani, Jamshid

    1995-01-01

    GridTool is designed around the concept that the surface grids are generated on a set of bi-linear patches. This type of grid generation is quite easy to implement, and it avoids the problems associated with complex CAD surface representations and associated surface parameterizations. However, the resulting surface grids are close to but not on the original CAD surfaces. This problem can be alleviated by projecting the resulting surface grids onto the original CAD surfaces. GridTool is designed primary for unstructured grid generation systems. Currently, GridTool supports VGRID and FELISA systems, and it can be easily extended to support other unstructured grid generation systems. The data in GridTool is stored parametrically so that once the problem is set up, one can modify the surfaces and the entire set of points, curves and patches will be updated automatically. This is very useful in a multidisciplinary design and optimization process. GridTool is written entirely in ANSI 'C', the interface is based on the FORMS library, and the graphics is based on the GL library. The code has been tested successfully on IRIS workstations running IRIX4.0 and above. The memory is allocated dynamically, therefore, memory size will depend on the complexity of geometry/grid. GridTool data structure is based on a link-list structure which allows the required memory to expand and contract dynamically according to the user's data size and action. Data structure contains several types of objects such as points, curves, patches, sources and surfaces. At any given time, there is always an active object which is drawn in magenta, or in their highlighted colors as defined by the resource file which will be discussed later.

  12. Smart Grid Risk Management

    Science.gov (United States)

    Abad Lopez, Carlos Adrian

    Current electricity infrastructure is being stressed from several directions -- high demand, unreliable supply, extreme weather conditions, accidents, among others. Infrastructure planners have, traditionally, focused on only the cost of the system; today, resilience and sustainability are increasingly becoming more important. In this dissertation, we develop computational tools for efficiently managing electricity resources to help create a more reliable and sustainable electrical grid. The tools we present in this work will help electric utilities coordinate demand to allow the smooth and large scale integration of renewable sources of energy into traditional grids, as well as provide infrastructure planners and operators in developing countries a framework for making informed planning and control decisions in the presence of uncertainty. Demand-side management is considered as the most viable solution for maintaining grid stability as generation from intermittent renewable sources increases. Demand-side management, particularly demand response (DR) programs that attempt to alter the energy consumption of customers either by using price-based incentives or up-front power interruption contracts, is more cost-effective and sustainable in addressing short-term supply-demand imbalances when compared with the alternative that involves increasing fossil fuel-based fast spinning reserves. An essential step in compensating participating customers and benchmarking the effectiveness of DR programs is to be able to independently detect the load reduction from observed meter data. Electric utilities implementing automated DR programs through direct load control switches are also interested in detecting the reduction in demand to efficiently pinpoint non-functioning devices to reduce maintenance costs. We develop sparse optimization methods for detecting a small change in the demand for electricity of a customer in response to a price change or signal from the utility

  13. Combining the GRID with Cloud for Earth Science Computing

    Science.gov (United States)

    Mishin, Dmitry; Levchenko, Oleg; Groudnev, Andrei; Zhizhin, Mikhail

    2010-05-01

    Cloud computing is a new economic model of using large cluster computing resources which were earlier managed by GRID. Reusing existing GRID infrastructure gives an opportunity to combine the Cloud and GRID technologies on the same hardware and to provide GRID users with functionality for running high performance computing tasks inside virtual machines. In this case Cloud works "above" GRID, sharing computing power and utilizing unused processor time. We manage virtual machines with Eucalyptus elastic cloud and we use Torque system from gLite infrastructure for spreading Cloud jobs in GRID computing nodes to scale the parallel computing tasks on virtual machines created by elastic cloud. For this purpose we have added new types of tasks to the standard GRID task list: to run a virtual node and to run a job on a virtual node. This gives a possibility to seamlessly upscale the Cloud with the new tasks when needed and to shrink it when the tasks are completed. Using GRID components for managing the size of a virtual cloud simplifies building the billing system to charge the Cloud users for the processor time, disk space and outer traffic consumed. A list of Earth Science computing problems that can be solved by using the elastic Cloud include repetitive tasks of downloading, converting and storing in a database of large arrays of data (e.g. weather forecast); creating a pyramid of lower resolution images from a very large one for fast distributed browsing; processing and analyzing the large distributed amounts of data by running Earth Science numerical models.

  14. Effect of panel shape of soccer ball on its flight characteristics

    Science.gov (United States)

    Hong, Sungchan; Asai, Takeshi

    2014-05-01

    Soccer balls are typically constructed from 32 pentagonal and hexagonal panels. Recently, however, newer balls named Cafusa, Teamgeist 2, and Jabulani were respectively produced from 32, 14, and 8 panels with shapes and designs dramatically different from those of conventional balls. The newest type of ball, named Brazuca, was produced from six panels and will be used in the 2014 FIFA World Cup in Brazil. There have, however, been few studies on the aerodynamic properties of balls constructed from different numbers and shapes of panels. Hence, we used wind tunnel tests and a kick-robot to examine the relationship between the panel shape and orientation of modern soccer balls and their aerodynamic and flight characteristics. We observed a correlation between the wind tunnel test results and the actual ball trajectories, and also clarified how the panel characteristics affected the flight of the ball, which enabled prediction of the trajectory.

  15. THE EFFECT OF GAMES AND TRAINING PROGRAMS OFFERED AT BALL SCHOOL (BALSCHULE, ON BALL-COORDINATION AMONG FIRST AND SECOND GRADE STUDENTS

    Directory of Open Access Journals (Sweden)

    Behrooz Ebrahimi

    2013-06-01

    Full Text Available The aim of this study is to investigate the effect of games and training programs offered at the Ball school (Ballschule Heidelberg, on ball-coordination among first and second grade students. For this purpose, 38 students from 13 schools covered by the Ball school (Heidelberg Balschule, were chosen as the experimental group (non-random ; in the meantime the consent of the students’ parents were also received. Forty students as well as a control group (non-random of eight normal schools were selected with parental consents. Then through using ball-coordination tests [BKT (BallKoordinationstests. Ball Coordination’s Tests], the level of the ball skills among both groups were measured in the pre-test and Post-test. Tests included kicking ball against the wall (under five conditions. The research methods were semi-experimental with experimental and control groups. Independent variables were also applied to the experimental group and the means and standard deviations were calculated through descriptive statistics. And then, a T-test for statistical analysis of data in related groups were applied. The results showed a significant effect of games and training programs offered at the school ball in the ball-coordination of subjects.

  16. Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

    OpenAIRE

    Mišković Žarko Z.; Mitrović Radivoje M.; Stamenić Zoran V.

    2016-01-01

    One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball be...

  17. Unifying representation of Bézier curve and two kinds of generalized ball curves

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiaolin; WANG Zhihua

    2012-01-01

    This paper presents a new basis, the WSB basis, which unifies the Bemstein basis, Wang-Ball basis and Said-Ball basis, and therefore the Bézier curve, Wang-Ball curve and Said-Ball curve are the special cases of the WSB curve based on the WSB basis In addition, the relative degree elevation formula, recursive algorithm and conversion formula between the WSB basis and the Bern- stein basis are given.

  18. Research on Abrasives in the Chemical Mechanical Polishing Process for Silicon Nitride Balls

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Silicon nitride (Si 3N 4) has been the main material for balls in ceramic ball bearings, for its lower density, high strength, high hardness, fine thermal stability and anticorrosive, and is widely used in various fields, such as high speed and high temperature areojet engines, precision machine tools and chemical engineer machines. Silicon nitride ceramics is a kind of brittle and hard material that is difficult to machining. In the traditional finishing process of silicon nitride balls, balls are lapped...

  19. The NorduGrid: Building a Production Grid in Scandinavia

    CERN Document Server

    Eerola, Paule Anna Mari; Ellert, M; Hansen, J R H; Konstantinov, A S; Kónya, B; Nielsen, JL; Ould-Saada, F; Smirnova, O G; Wäänänen, A

    2002-01-01

    The aim of the NorduGrid project is to build and operate a production Grid infrastructure in Scandinavia and Finland. The innovative middleware solutions allowed to set up a working testbed, which connects dynamic set of computing resources by providing a uniform access to them. The resources range from small test clusters of academic institutions to large farms of various supercomputer centers. This paper reviews the architecture and describes the Grid services, implemented via the NorduGrid middleware. As an example of a demanding application, a real use case of a High Energy Physics study is described.

  20. Temporomandibular joint dislocation and deafness from a cricket ball injury.

    Science.gov (United States)

    Murthy, P; Bandasson, C; Dhillon, R S

    1994-05-01

    Cricket is a national sport in some countries and can be potentially hazardous. We report an incident of a cricket ball impact to the chin, which resulted in posterior dislocation of both temporomandibular joints and bilateral mixed deafness. There appear to be no similar case reports in the literature.

  1. Experimental signatures of supersymmetric dark-matter Q-balls

    OpenAIRE

    Kusenko, Alexander; Kuzmin, Vadim; Shaposhnikov, Mikhail E.; Tinyakov, P. G.

    1997-01-01

    Theories with low-energy supersymmetry predict the existence of stable non-topological solitons, Q-balls, that can contribute to dark matter. We discuss the experimental signatures, methods of detection, and the present limits on such dark matter candidates.

  2. Reduced graphene oxide synthesis by high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, O. [Department of Physics, M.U.C Women' s College, Burdwan 713104 (India); Mitra, S. [MLS Prof' s Unit, Indian Association for the Cultivation of Science, Kolkata 700032 (India); Pal, M. [CSIR-Central Glass and Ceramic Research Institute, Kolkata 700032 (India); Datta, A. [University School of Basic and Applied Science (USBAS), Guru Gobind Singh Indraprastha University, New Delhi 110075 (India); Dhara, S. [Surface and Nanoscience Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Chakravorty, D., E-mail: mlsdc@iacs.res.in [MLS Prof' s Unit, Indian Association for the Cultivation of Science, Kolkata 700032 (India)

    2015-07-01

    Graphene oxide is transformed to reduced graphene oxide by high energy ball milling in inert atmosphere. The process of ball milling introduces defects and removes oxygen functional groups, thereby creating the possibility of fine tuning the band gap of all intermediate stages of the structural evolution. A limit of the backbone sp{sup 2} network structure has been found which should be able to accommodate defects, before amorphization sets in. The amorphization of graphene oxide is achieved rather quickly in comparison to that of graphite. From thermogravimetric and differential scanning calorimetric analysis along with Fourier transform infrared (FTIR) and Raman spectroscopic studies, it is found that the number of oxygen-containing groups decreases at a faster rate than that of aromatic double bonds with increasing ball milling time with a maximum limit of 3 h. Several characterization techniques (FTIR, Raman, UV–Visible and X-ray photoelectron spectroscopy) have confirmed that the material synthesized is, indeed, reduced graphene oxide. - Highlights: • Graphene oxide is transformed to reduced graphene oxide by high energy ball milling in inert atmosphere. • Fine tuning the band gap by introducing defects and removing oxygen functional groups. • Introduction of excess defects leads to amorphization. • Photoluminescence has been observed in the UV-blue region.

  3. Reduced graphene oxide synthesis by high energy ball milling

    International Nuclear Information System (INIS)

    Graphene oxide is transformed to reduced graphene oxide by high energy ball milling in inert atmosphere. The process of ball milling introduces defects and removes oxygen functional groups, thereby creating the possibility of fine tuning the band gap of all intermediate stages of the structural evolution. A limit of the backbone sp2 network structure has been found which should be able to accommodate defects, before amorphization sets in. The amorphization of graphene oxide is achieved rather quickly in comparison to that of graphite. From thermogravimetric and differential scanning calorimetric analysis along with Fourier transform infrared (FTIR) and Raman spectroscopic studies, it is found that the number of oxygen-containing groups decreases at a faster rate than that of aromatic double bonds with increasing ball milling time with a maximum limit of 3 h. Several characterization techniques (FTIR, Raman, UV–Visible and X-ray photoelectron spectroscopy) have confirmed that the material synthesized is, indeed, reduced graphene oxide. - Highlights: • Graphene oxide is transformed to reduced graphene oxide by high energy ball milling in inert atmosphere. • Fine tuning the band gap by introducing defects and removing oxygen functional groups. • Introduction of excess defects leads to amorphization. • Photoluminescence has been observed in the UV-blue region

  4. Predicting brain acceleration during heading of soccer ball

    Science.gov (United States)

    Taha, Zahari; Hasnun Arif Hassan, Mohd; Azri Aris, Mohd; Anuar, Zulfika

    2013-12-01

    There has been a long debate whether purposeful heading could cause harm to the brain. Studies have shown that repetitive heading could lead to degeneration of brain cells, which is similarly found in patients with mild traumatic brain injury. A two-degree of freedom linear mathematical model was developed to study the impact of soccer ball to the brain during ball-to-head impact in soccer. From the model, the acceleration of the brain upon impact can be obtained. The model is a mass-spring-damper system, in which the skull is modelled as a mass and the neck is modelled as a spring-damper system. The brain is a mass with suspension characteristics that are also defined by a spring and a damper. The model was validated by experiment, in which a ball was dropped from different heights onto an instrumented dummy skull. The validation shows that the results obtained from the model are in a good agreement with the brain acceleration measured from the experiment. This findings show that a simple linear mathematical model can be useful in giving a preliminary insight on what human brain endures during a ball-to-head impact.

  5. Whitey SCHe Ball Valves Provide Test Port Isolation

    Energy Technology Data Exchange (ETDEWEB)

    MISKA, C.R.

    2000-09-15

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They are used as normally closed isolation valves for test ports in the SCHe System between the gage root valve and the pressure indicator.

  6. Weighted Composition Operators between Hardy Spaces on the Unit Ball

    Institute of Scientific and Technical Information of China (English)

    XUHui-ming; LIUTai-shun

    2004-01-01

    We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the operator from H1 to H1 is compact if and only if it is weakly compact. Meanwhile, we get the analogue on the Bergman spaces.

  7. On the isoperimetric rigidity of extrinsic minimal balls

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2003-01-01

    We consider an m-dimensional minimal submanifold P and a metric R-sphere in the Euclidean space R-n. If the sphere has its center p on P, then it will cut out a well defined connected component of P which contains this center point. We call this connected component an extrinsic minimal R-ball of ...

  8. Female football players don't have balls

    OpenAIRE

    Lippe, Gerd von der

    2008-01-01

    You need balls to play football. So it is obvious that being a girl just won't do as far as the guys are concerned, says Gerd von der Lippe in a devastating critique of the state of affairs in the reporting and support of women's football in Norway.

  9. Molecular Similarity Based on Super-Ball Algorithm

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The molecular similarity of 139 organic compounds was calculated by the topologic index method, the flexible super-ball algorithm was used to scan similar molecules and structures. The results show that the properties of organic compounds estimated from this method are reliable.

  10. Weighted Plancherel formula on unit ball in R

    Institute of Scientific and Technical Information of China (English)

    刘建明; 郑维行

    1996-01-01

    Let / be a function on the unit ball of Rn. For , the action T of SO0 (1, n) on f isdefined by .The invariant Laplacian corresponding to T is calculated, and a family of its eigenfunctions is found out. Then the corresponding Fourier transform is defined and the inversion formula and Plancherel formula are obtained.

  11. Astroblaster--A Fascinating Game of Multi-Ball Collisions

    Science.gov (United States)

    Kires, Marian

    2009-01-01

    Multi-ball collisions inside the Astroblaster toy are explained from the conservation of momentum point of view. The important role of the coefficient of restitution is demonstrated in ideal and real cases. Real experimental results with the simple toy can be compared with a computer model represented by an interactive Java applet. (Contains 1…

  12. On the Quaternion Ball and the Quaternion Projective Space

    Institute of Scientific and Technical Information of China (English)

    Qi Keng LU

    2005-01-01

    Since the quaternion ball was used to study the AdS/CFT problems for spinor fields, it is worthwhile to study further the geometry (in sense of Klein) and analysis on it and on its extended space (in the sense of Behnke-Thullen), the quaternion projective space.

  13. Systematization of problems on ball estimates of a convex compactum

    Science.gov (United States)

    Dudov, S. I.

    2015-09-01

    We consider a class of finite-dimensional problems on the estimation of a convex compactum by a ball of an arbitrary norm in the form of extremal problems whose goal function is expressed via the function of the distance to the farthest point of the compactum and the function of the distance to the nearest point of the compactum or its complement. Special attention is devoted to the problem of estimating (approximating) a convex compactum by a ball of fixed radius in the Hausdorff metric. It is proved that this problem plays the role of the canonical problem: solutions of any problem in the class under consideration can be expressed via solutions of this problem for certain values of the radius. Based on studying and using the properties of solutions of this canonical problem, we obtain ranges of values of the radius in which the canonical problem expresses solutions of the problems on inscribed and circumscribed balls, the problem of uniform estimate by a ball in the Hausdorff metric, the problem of asphericity of a convex body, the problems of spherical shells of the least thickness and of the least volume for the boundary of a convex body. This makes it possible to arrange the problems in increasing order of the corresponding values of the radius. Bibliography: 34 titles.

  14. The spectacle of the ball python (Python regius)

    DEFF Research Database (Denmark)

    Da Silva, Mari-Ann O; Heegaard, Steffen; Wang, Tobias;

    2014-01-01

    A detailed morphological description of the spectacle of the ball python (Python regius) is provided. The eyes of 21 snakes were examined by light microscopy and/or transmission electron microscopy. Additionally, eyes of nine live snakes were examined using optical coherence tomography (OCT...

  15. Eric Cantona: Fußball-Ikone der modernen Medienwelt

    Directory of Open Access Journals (Sweden)

    Martin Wassermair

    2010-03-01

    Full Text Available In Unterhaltungsindustrie und Massenmedien nimmt der Sport eine im wahrsten Sinne des Wortes bewegende Rolle ein. Er ist zugleich Wettkampf-Arena und Wunschmaschine, Werbefläche und Starproduktion. Dass die Erscheinungsformen des Sports in der modernen Medienwelt einer rasanten Dynamik und Wechselbeziehung unterliegen, ist am Beispiel des Massenphänomens Fußballs vielleicht am deutlichsten abzulesen.

  16. These Kids Are Really on the Ball! Invention Competition Winners

    Science.gov (United States)

    Tech Directions, 2008

    2008-01-01

    Judge Harry T. Roman, an electrical engineer and inventor himself, has selected the best entries in the 2007-2008 "Tech Directions" Inventors Award Competition. This year's challenge called for students to devise new uses for the common Ping-Pong ball. Of the results, the judge notes "The ideas submitted were most interesting, with a high number…

  17. Preparation of iron sulphides by high energy ball milling

    DEFF Research Database (Denmark)

    Lin, R.; Jiang, Jianzhong; Larsen, R.K.;

    1998-01-01

    The reaction of a powder mixture consisting of 50 a.% Fe and 50 a.% S during high energy ball milling has been studied by x-ray diffraction and Mossbauer spectroscopy. After around 19 h of milling FeS2 and FeS havebeen formed. By further milling the FeS compound becomes dominating and only Fe...

  18. LINEAR SINGULAR INTEGRAL EQUATION ON DOMAINS COMPOSED BY BALLS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For domains composed by balls in Cn, this paper studies the boundary behaviour of Cauchy type integrals with discrete holomorphic kernels and the corresponding linear singular integral equation on each piece of smooth lower dimensional edges on the boundary of the domain.

  19. Application of the Blobo bluetooth ball in wrist rehabilitation training.

    Science.gov (United States)

    Hsieh, Wei-Min; Hwang, Yuh-Shyan; Chen, Shih-Ching; Tan, Sun-Yen; Chen, Chih-Chen; Chen, Yu-Luen

    2016-01-01

    [Purpose] The introduction of emerging technologies such as the wireless Blobo bluetooth ball with multimedia features can enhance wrist physical therapy training, making it more fun and enhancing its effects. [Methods] Wrist injuries caused by fatigue at work, improper exercise, and other conditions are very common. Therefore, the reconstruction of wrist joint function is an important issue. The efficacy of a newly developed integrated wrist joint rehabilitation game using a Blobo bluetooth ball with C# software installed was tested in wrist rehabilitation (Flexion, Extension, Ulnar Deviation, Radial Deviation). [Results] Eight subjects with normal wrist function participated in a test of the system's stability and repeatability. After performing the Blobo bluetooth ball wrist physical therapy training, eight patients with wrist dysfunction experienced approximately 10° improvements in range of motion (ROM) of flexion extension, and ulnar deviation and about 6° ROM improvement in radial deviation. The subjects showed progress in important indicators of wrist function. [Conclusion] This study used the Blobo bluetooth ball in wrist physical therapy training and the preliminary results were encouraging. In the future, more diverse wrist or limb rehabilitation games should be developed to meet the needs of physical therapy training. PMID:26957723

  20. Thump, ring: the sound of a bouncing ball

    Energy Technology Data Exchange (ETDEWEB)

    Katz, J I, E-mail: katz@wuphys.wustl.ed [Department of Physics and McDonnell Center for the Space Sciences, Washington University, St Louis, MO 63130 (United States)

    2010-07-15

    A basketball bounced on a stiff surface produces a characteristic loud thump, followed by a high-pitched ringing. Describing the ball as an inextensible but flexible membrane containing compressed air, I formulate an approximate theory of the generation of these sounds and predict their amplitudes and waveforms.

  1. Thump, ring: the sound of a bouncing ball

    CERN Document Server

    Katz, J I

    2008-01-01

    A basketball bounced on a stiff surface produces a characteristic loud thump, followed by high-pitched ringing. Describing the ball as an inextensible but flexible membrane containing compressed air, I formulate an approximate theory of the generation of these sounds and predict their amplitudes and waveforms.

  2. Nocardia asteroids causing pulmonary nocardiosis presenting as fungal ball

    Directory of Open Access Journals (Sweden)

    Bimoch Projna Paty

    2014-01-01

    Full Text Available Pulmonary nocardiosis presenting as a fungal ball in a preexisting cavity is a rare presentation. We report such a case in a 18 yrs old male patient presented with cough with expectoration & episodes of haemoptysis with a past history of tuberculosis. Diagnosis was done by microscopic examination of the resected sample & confirmed on culture.

  3. From the Lab Bench: The invisible crystal ball

    Science.gov (United States)

    A column was written that pondered that advantages of a livestock producer having a crystal ball in their head that could tell you weather patterns, cattle markets, calf crops, etc. You would have such an advantage that there is no reason for your farming operation to fail. The column went through...

  4. Smart power grids 2011

    CERN Document Server

    Keyhani, Ali

    2012-01-01

    Electric power systems are experiencing significant changes at the worldwide scale in order to become cleaner, smarter, and more reliable. This edited book examines a wide range of topics related to these changes, which are primarily caused by the introduction of information technologies, renewable energy penetration, digitalized equipment, new operational strategies, and so forth. The emphasis will be put on the modeling and control of smart grid systems. This book addresses research topics such as high efficiency transforrmers, wind turbines and generators, fuel cells, or high speed turbines

  5. The Knowledge Grid

    CERN Document Server

    Zhuge, Hai

    2004-01-01

    The Knowledge Grid is an intelligent and sustainable interconnection environment that enables people and machines to effectively capture, publish, share and manage knowledge resources. It also provides appropriate on-demand services to support scientific research, technological innovation, cooperative teamwork, problem solving, and decision making. It incorporates epistemology and ontology to reflect human cognitive characteristics; exploits social, ecological and economic principles; and adopts techniques and standards developed during work toward the future web. This book presents its methodology, theory, models and applications systematically for the first time.

  6. Effect of aging on rheology of ball clay suspensions

    Science.gov (United States)

    Tonthai, Tienchai

    2002-01-01

    The behaviors of clay-water suspensions such as deflocculation or rheological properties are not constant but change with time. Aging has been recognized for changing the rheological properties of clay suspensions. This work provided information about the effects of the moisture contents in ball clay lumps and clay air exposure time on their processability. Dynamic oscillatory rheometry using a vane-in-cup geometry was used to characterize the rheological behavior of ball clay suspensions in terms of elastic modulus, viscous modulus and yield stress as a function of aging time. A light scattering size analyzer was used to examine the agglomerate size distribution of ball clay suspensions which affected the rheological behavior. Soluble ion release (both cations and anions) in the filtrate of suspensions was measured by ion chromatography. Low and high lignitic ball clay suspensions were dispersed with sodium silicate (Na2SiO3) or sodium polyacrylate at specific gravity 1.3 and 1.6 in two dispersion states: fully deflocculated (minimum viscosity) and under deflocculated. Suspensions prepared using freshly mined ball clays required more dispersant than suspensions prepared using dry ball clays to achieve minimum viscosity due to a difference in agglomerate size distribution. The agglomerate size distribution of suspensions prepared using dry clays was broader than that of suspensions prepared using freshly mined clays. In suspensions prepared using freshly mined clays, there were many uniformly small agglomerates having loose water inside, while in suspensions prepared using dry clays, the capillary effect and bonding between clay particles resulting from drying broke clay aggregates apart into agglomerate structures composed of a few to many clay particles. For suspensions prepared using dry clays after one day suspension aging, the elastic modulus and yield stress decreased due to the change in agglomerate size distribution of suspensions but increased for

  7. Rolling Motion of a Ball Spinning about a Near-Vertical Axis

    Science.gov (United States)

    Cross, Rod

    2012-01-01

    A ball that is projected forward without spin on a horizontal surface will slide for a short distance before it starts rolling. Sliding friction acts to decrease the translation speed v and it acts to increase the rotation speed [omega]. When v = R[omega], where R is the ball radius, the ball will start rolling and the friction force drops almost…

  8. 76 FR 10335 - Ball Bearings and Parts Thereof From Germany: Initiation of Antidumping Duty Changed...

    Science.gov (United States)

    2011-02-24

    ..., 75 FR 37759 (June 30, 2010). After analysis of the quantity and value of the sales of ball bearings... FR 20900 (May 15, 1989). On June 30, 2010, we initiated an administrative review of the order on ball... International Trade Administration Ball Bearings and Parts Thereof From Germany: Initiation of Antidumping...

  9. Synchrony-optimized power grids

    CERN Document Server

    Pinto, Rafael S

    2014-01-01

    We investigate synchronization in power grids, which we assume to be modeled by a network of Kuramoto oscillators with inertia. More specifically, we study the optimization of the power grid topology to favor the network synchronization. We introduce a rewiring algorithm which consists basically in a hill climb scheme where the edges of the network are swapped in order enhance the main measures of synchronization. As a byproduct of the optimization algorithm, we typically have also the anticipation of the synchronization onset for the optimized network. We perform several robustness tests for the synchrony-optimized power grids, including the impact of consumption peaks. In our analyses, we investigate synthetic random networks, which we consider as hypothetical decentralized power generation situations, and also a network based in the actual power grid of Spain, which corresponds to the current paradigm of centralized power grids. The synchrony-optimized power grids obtained by our algorithm have some intere...

  10. Workshop on Future Generation Grids

    CERN Document Server

    Laforenza, Domenico; Reinefeld, Alexander

    2006-01-01

    The Internet and the Web continue to have a major impact on society. By allowing us to discover and access information on a global scale, they have created entirely new businesses and brought new meaning to the term surf. In addition, however, we want processing, and increasingly, we want collaborative processing within distributed teams. This need has led to the creation of the Grid - an infrastructure that enables us to share capabilities, and integrate services and resources within and across enterprises. "Future Generation Grids" is the second in the "CoreGRID" series. This edited volume brings together contributed articles by scientists and researchers in the Grid community in an attempt to draw a clearer picture of the future generation Grids. This book also identifies some of the most challenging problems on the way to achieving the invisible Grid ideas

  11. The Maya ball game. Comparison of the physical load with modern ball games.

    Science.gov (United States)

    Blümchen, Gerhard

    2009-01-01

    The Maya ball game (MBG) originated more than 3,000 years ago. As best as is now known from archaeological and iconographical sources as well as the structure of the sport courts, this was a very physically taxing and important part of Mayan culture. The objective of this paper was to determine the physical load on those who participated in MBG as best as could be done from present perspectives. The load appears to be similar to that observed in soccer-tennis, in which heart rate rises to 140-160 beats/min and systolic blood pressure to 150-170 mm Hg. This is considered a light-to-moderate workload (4.5-5.5 metabolic equivalents) comparable to intensities reached in baseball, cycling (10 km/h), cross-country skiing (7 km/h), tournament dancing, swimming (2 km/h), doubles tennis and hiking (7 km/h). Thus, the cardiovascular demands of popular sports seem to have remained relatively similar through several millennia. PMID:19246899

  12. Design and implementation of HEP grid portal

    International Nuclear Information System (INIS)

    Grid Portal is an important part of grid research. This paper presents the structure design, functions and related implementation of HEP Grid portal, which is designed based on the idea of service-oriented, and uses the portlets to call on Grid Service supported by LCG Grid, so physical scientists can use HEP Grid Portal as a secure and convenient interface to visit all kinds of resource provided by HEP GRID. (authors)

  13. 3G POWER GRID SYSTEM

    OpenAIRE

    Saiyad Tausif Ali *; Gaurav Pawar; Pragati Rathi; Mandar Pathak

    2016-01-01

    3G Power grid system is dual side stream of electricity and automated construct information and distributed advanced energy delivery network. In this 3G Power grid system avoided the thermal and hydro sources of energy. By using the solar power and wind power energy will generate electricity according with the condition of nature. 3G Power grid system provides the facility of generating as well as marketing of electricity not only for the producers but also for consumers. By using megabytes o...

  14. Smart Grid Technologies and Implementations

    OpenAIRE

    Zhang, Haotian

    2014-01-01

    Smart grid has been advocated in both developing and developed countries in many years to deal with large amount of energy deficit and air pollutions. However, many literatures talked about some specific technologies and implementations, few of them could give a clear picture on the smart grid implementations in a macro scale like what is the main consideration for the smart grid implementations, how to examine the power system operation with communication network deployment, how to determine...

  15. Smart Grid Enabled EVSE

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-10-15

    The combined team of GE Global Research, Federal Express, National Renewable Energy Laboratory, and Consolidated Edison has successfully achieved the established goals contained within the Department of Energy’s Smart Grid Capable Electric Vehicle Supply Equipment funding opportunity. The final program product, shown charging two vehicles in Figure 1, reduces by nearly 50% the total installed system cost of the electric vehicle supply equipment (EVSE) as well as enabling a host of new Smart Grid enabled features. These include bi-directional communications, load control, utility message exchange and transaction management information. Using the new charging system, Utilities or energy service providers will now be able to monitor transportation related electrical loads on their distribution networks, send load control commands or preferences to individual systems, and then see measured responses. Installation owners will be able to authorize usage of the stations, monitor operations, and optimally control their electricity consumption. These features and cost reductions have been developed through a total system design solution.

  16. Data Exchange in Grid Workflow

    Institute of Scientific and Technical Information of China (English)

    ZENG Hongwei; MIAO Huaikou

    2006-01-01

    In existing web services-based workflow, data exchanging across the web services is centralized, the workflow engine intermediates at each step of the application sequence.However, many grid applications, especially data intensive scientific applications, require exchanging large amount of data across the grid services.Having a central workfiow engine relay the data between the services would results in a bottleneck in these cases.This paper proposes a data exchange model for individual grid workflow and multiworkflows composition respectively.The model enables direct communication for large amounts of data between two grid services.To enable data to exchange among multiple workflows, the bridge data service is used.

  17. The salience and complexity of building, regulating, and governing the smart grid: Lessons from a statewide public–private partnership

    International Nuclear Information System (INIS)

    Smart grid deployment unfolds within a diverse array of multi-institutional arrangements that may be too fragmented and decentralized to allow for the kind of large-scale and coordinated investments needed to properly deploy the smart grid. This case study provides an account of how one state arranged for and eventually deployed smart grid technology to over 85 percent of its resident. The study asks: does the deployment of the smart grid introduce new socio-political variables into the electricity distribution industry? To make sense of the socio-political variables shaping the industry and regulators, the Salience–Complexity Model is used to assess whether the smart grid raises or lowers the level of public scrutiny caste upon the industry (issue salience) and the level of technical capacity needed to execute and utilize the smart grid (technical complexity). The conclusions to be drawn from this study include: smart grid technology heightens the issue salience and the technical complexity of electricity distribution, but that the smart grid will likely not have a significant impact on the restructuring of electricity regulation. - Highlights: • Smart grid introduces new socio-political variables into the electricity distribution industry. • Smart grid technology engenders high degrees of issue salience and technical complexity. • Smart grid deployment requires extensive industry-regulator collaboration. • Smart grid will likely not have a significant impact on the restructuring of electricity regulation

  18. 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.

  19. 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 capill

  20. Historiografia del “Ball de Torrent”: De la moixiganga barroca al quadre de balls populars valencians (1692-1929

    Directory of Open Access Journals (Sweden)

    Raül Sanchis Francés

    2013-06-01

    Full Text Available Resum: El Ball de Torrent és una moixiganga dramàtica popular escenificada a la ciutat de València i altres indrets del País Valencià des de finals del segle XVII fins a principis del segle XX. Estava organitzada per agrupacions gremials, juntes d’hospitals o clavaris de festes i protagonitzada per personatges agrupats en comparses que representaven una paròdia sobre les relacions entre les estructures de poder i les classes populars. Tot i la variabilitat segons el moment històric, es conforma com una mescla de quadres amb danses, música i jocs teatrals. El ball interacciona de diverses formes amb algunes festes valencianes i és, probablement, una de les mostres de teatre de carrer més nostrades i menys estudiades de la València Moderna. En aquest article es realitza una revisió bibliogràfica crítica i una primera anàlisi historiogràfica.Paraules clau: Ball de Torrent, Dansa i música tradicional, Teatre, Moixiganga, Festa valencianaAbstract: Ball de Torrent (Dance of Torrent is a popular dramatic masquerade staged in Valencia since the late seventeenth century to the early twentieth. It was organized by guilds, hospital managements or festival organizers. The actors were grouped in associations representing a parody on the relationships between power structures and popular classes. Despite the variability depending on the historical period, it consisted of a mixture of episodes or scenes with dance, music and theatre games. Any Festivals in Valencia are connected with the Ball de Torrent. It’s probably one of the most interesting samples of street theatre and studied under of the Modern Valencia. This paper analyses historical sources to review and critique bibliography.Keywords: Dance of Torrent, Traditional Dance and Music, Theatre, Masquerade, Feasts of Valencia

  1. Ball-milled sulfur-doped graphene materials contain metallic impurities originating from ball-milling apparatus: their influence on the catalytic properties.

    Science.gov (United States)

    Chua, Chun Kiang; Sofer, Zdeněk; Khezri, Bahareh; Webster, Richard D; Pumera, Martin

    2016-07-21

    Graphene materials have found applications in a wide range of devices over the past decade. In order to meet the demand for graphene materials, various synthesis methods are constantly being improved or invented. Ball-milling of graphite to obtain graphene materials is one of the many versatile methods to easily obtain bulk quantities. In this work, we show that the graphene materials produced by ball-milling are spontaneously contaminated with metallic impurities originating from the grinding bowls and balls. Ball-milled sulfur-doped graphene materials obtained from two types of ball-milling apparatus, specifically made up of stainless steel and zirconium dioxide, were investigated. Zirconium dioxide-based ball-milled sulfur-doped graphene materials contain a drastically lower amount of metallic impurities than stainless steel-based ball-milled sulfur-doped graphene materials. The presence of metallic impurities is demonstrated by their catalytic effects toward the electrochemical catalysis of hydrazine and cumene hydroperoxide. The general impression toward ball-milling of graphite as a versatile method for the bulk production of 'metal-free' graphene materials without the need for post-processing and the selection of ball-milling tools should be cautioned. These findings would have wide-reaching implications for graphene research.

  2. Ball-milled sulfur-doped graphene materials contain metallic impurities originating from ball-milling apparatus: their influence on the catalytic properties.

    Science.gov (United States)

    Chua, Chun Kiang; Sofer, Zdeněk; Khezri, Bahareh; Webster, Richard D; Pumera, Martin

    2016-07-21

    Graphene materials have found applications in a wide range of devices over the past decade. In order to meet the demand for graphene materials, various synthesis methods are constantly being improved or invented. Ball-milling of graphite to obtain graphene materials is one of the many versatile methods to easily obtain bulk quantities. In this work, we show that the graphene materials produced by ball-milling are spontaneously contaminated with metallic impurities originating from the grinding bowls and balls. Ball-milled sulfur-doped graphene materials obtained from two types of ball-milling apparatus, specifically made up of stainless steel and zirconium dioxide, were investigated. Zirconium dioxide-based ball-milled sulfur-doped graphene materials contain a drastically lower amount of metallic impurities than stainless steel-based ball-milled sulfur-doped graphene materials. The presence of metallic impurities is demonstrated by their catalytic effects toward the electrochemical catalysis of hydrazine and cumene hydroperoxide. The general impression toward ball-milling of graphite as a versatile method for the bulk production of 'metal-free' graphene materials without the need for post-processing and the selection of ball-milling tools should be cautioned. These findings would have wide-reaching implications for graphene research. PMID:27314607

  3. Modeling Neutral Densities Downstream of a Gridded Ion Thruster

    Science.gov (United States)

    Soulas, George C.

    2010-01-01

    The details of a model for determining the neutral density downstream of a gridded ion thruster are presented. An investigation of the possible sources of neutrals emanating from and surrounding a NEXT ion thruster determined that the most significant contributors to the downstream neutral density include discharge chamber neutrals escaping through the perforated grids, neutrals escaping from the neutralizer, and vacuum facility background neutrals. For the neutral flux through the grids, near- and far-field equations are presented for rigorously determining the neutral density downstream of a cylindrical aperture. These equations are integrated into a spherically-domed convex grid geometry with a hexagonal array of apertures for determining neutral densities downstream of the ion thruster grids. The neutrals escaping from an off-center neutralizer are also modeled assuming diffuse neutral emission from the neutralizer keeper orifice. Finally, the effect of the surrounding vacuum facility neutrals is included and assumed to be constant. The model is used to predict the neutral density downstream of a NEXT ion thruster with and without neutralizer flow and a vacuum facility background pressure. The impacts of past simplifying assumptions for predicting downstream neutral densities are also examined for a NEXT ion thruster.

  4. Surge Control of a Centrifugal Compression System by Using a Bouncing Ball

    Institute of Scientific and Technical Information of China (English)

    Yuichiro Asaga; Shimpei Mizuki; Hoshio Tsujita; Shinsuke Ohta

    2008-01-01

    The purpose of this study is to suppress the fluctuations of surge by a simple passive control method. A bouncing ball system with different weight of the balls was tested. As a result, the bouncing ball system suppressed mild surge without the deterioration of the performance characteristics, and moved the initiation point of surge toward the lower flow rate when the steel ball of 15mm outer diameter was used. The present system was effective to suppress the surge and to widen the stable operating range of a centrifugal compressor when the ball was chosen appropriately.

  5. 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

  6. Knowledge Base Grid: A Generic Grid Architecture for Semantic Web

    Institute of Scientific and Technical Information of China (English)

    WU ZhaoHui(吴朝晖); CHEN HuaJun(陈华钧); XU JieFeng(徐杰锋)

    2003-01-01

    The emergence of semantic web will result in an enormous amount of knowledge base resources on the web. In this paper, a generic Knowledge Base Grid Architecture (KB-Grid)for building large-scale knowledge systems on the semantic web is presented. KB-Grid suggests a paradigm that emphasizes how to organize, discover, utilize, and manage web knowledge base resources. Four principal components are under development: a semantic browser for retrieving and browsing semantically enriched information, a knowledge server acting as the web container for knowledge, an ontology server for managing web ontologies, and a knowledge base directory server acting as the registry and catalog of KBs. Also a referential model of knowledge service and the mechanisms required for semantic communication within KB-Grid are defined. To verify the design rationale underlying the KB-Grid, an implementation of Traditional Chinese Medicine(TCM) is described.

  7. 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...

  8. A new principle and device for large aircraft components gaining accurate support by ball joint

    Institute of Scientific and Technical Information of China (English)

    Bao-gui QIU; Jun-xia JIANG; Ying-lin KE

    2011-01-01

    How to obtain an accurate support for large components by ball joint is a key process in aircraft digital assembly. A novel principle and device is developed to solve the problem. Firstly, the working principle of the device is introduced. When three or four displacement sensors installed in the localizer are touched by the ball-head, the spatial relation is calculated between the large aircraft component's ball-head and the localizer's ball-socket. The localizer is driven to achieve a new position by compensation. Relatively, a support revising algorithm is proposed. The localizer's ball-socket approaches the ball-head based on the displacement sensors. According to the points selected from its spherical surface, the coordinates of ball-head spherical center are computed by geometry. Finally, as a typical application, the device is used to conduct a test-fuselage's ball-head into a localizer's ball-socket. Positional deviations of the spherical centers between the ball-head and the ball-socket in the x, y, and z directions are all controlled within ±0.05 mm under various working conditions. The results of the experiments show that the device has the characteristics of high precision, excellent stability, strong operability, and great potential to be applied widely in the modern aircraft industry.

  9. The head tracks and gaze predicts: how the world's best batters hit a ball.

    Directory of Open Access Journals (Sweden)

    David L Mann

    Full Text Available Hitters in fast ball-sports do not align their gaze with the ball throughout ball-flight; rather, they use predictive eye movement strategies that contribute towards their level of interceptive skill. Existing studies claim that (i baseball and cricket batters cannot track the ball because it moves too quickly to be tracked by the eyes, and that consequently (ii batters do not - and possibly cannot - watch the ball at the moment they hit it. However, to date no studies have examined the gaze of truly elite batters. We examined the eye and head movements of two of the world's best cricket batters and found both claims do not apply to these batters. Remarkably, the batters coupled the rotation of their head to the movement of the ball, ensuring the ball remained in a consistent direction relative to their head. To this end, the ball could be followed if the batters simply moved their head and kept their eyes still. Instead of doing so, we show the elite batters used distinctive eye movement strategies, usually relying on two predictive saccades to anticipate (i the location of ball-bounce, and (ii the location of bat-ball contact, ensuring they could direct their gaze towards the ball as they hit it. These specific head and eye movement strategies play important functional roles in contributing towards interceptive expertise.

  10. Trajectory-based ball detection and tracking with aid of homography in broadcast tennis video

    Science.gov (United States)

    Yu, Xinguo; Jiang, Nianjuan; Ang, Ee Luang

    2007-01-01

    Ball-detection-and-tracking in broadcast tennis video (BTV) is a crucial but challenging task in tennis video semantics analysis. Informally, the challenges are due to camera motion and the other causes such as the presence of many ball-like objects and the small size of the tennis ball. The trajectory-based approach proposed by us in our previous papers mainly counteracted the challenges imposed by causes other than camera motion and achieves a good performance. This paper proposes an improved trajectory-based ball detection and tracking algorithm in BTV with the aid of homography, which counteracts the challenges caused by camera motion and bring us multiple new merits. Firstly, it acquires an accurate homography, which transforms each frame into the "standard" frame. Secondly, it achieved higher accuracy of ball identification. Thirdly, it obtains the ball projection position in the real world, instead of ball location in the image. Lastly, it also identifies landing frames and positions of the ball. The experimental results show that the improved algorithm can obtain not only higher accuracy in ball identification and in ball position alike, but also ball landing frames and positions. With the intent of using homography to improve the video-based event detection for smart home we also do some experiments on acquiring the homography for home surveillance video.

  11. The Open Science Grid

    CERN Document Server

    Pordes, Ruth; Olson, Doug; Livny, Miron; Roy, Alain; Avery, Paul; Blackburn, Kent; Wenaus, Torre; Wuerthwein, Frank K.; Gardner, Rob; Wilde, Mike; Blatecky, Alan; McGee, John; Quick, Rob

    2007-01-01

    The Open Science Grid (OSG) provides a distributed facility where the Consortium members provide guaranteed and opportunistic access to shared computing and storage resources. OSG provides support for and evolution of the infrastructure through activities that cover operations, security, software, troubleshooting, addition of new capabilities, and support for existing and engagement with new communities. The OSG SciDAC-2 project provides specific activities to manage and evolve the distributed infrastructure and support it's use. The innovative aspects of the project are the maintenance and performance of a collaborative (shared & common) petascale national facility over tens of autonomous computing sites, for many hundreds of users, transferring terabytes of data a day, executing tens of thousands of jobs a day, and providing robust and usable resources for scientific groups of all types and sizes. More information can be found at the OSG web site: www.opensciencegrid.org.

  12. The open science grid

    International Nuclear Information System (INIS)

    The Open Science Grid (OSG) provides a distributed facility where the Consortium members provide guaranteed and opportunistic access to shared computing and storage resources. OSG provides support for and evolution of the infrastructure through activities that cover operations, security, software, troubleshooting, addition of new capabilities, and support for existing and engagement with new communities. The OSG SciDAC-2 project provides specific activities to manage and evolve the distributed infrastructure and support it's use. The innovative aspects of the project are the maintenance and performance of a collaborative (shared and common) petascale national facility over tens of autonomous computing sites, for many hundreds of users, transferring terabytes of data a day, executing tens of thousands of jobs a day, and providing robust and usable resources for scientific groups of all types and sizes. More information can be found at the OSG web site: www.opensciencegrid.org

  13. The open science grid

    Energy Technology Data Exchange (ETDEWEB)

    Pordes, Ruth [Fermi National Accelerator Laboratory (United States); Petravick, Don [Fermi National Accelerator Laboratory (United States); Kramer, Bill [Lawrence Berkeley National Laboratory (United States); Olson, Doug [Lawrence Berkeley National Laboratory (United States); Livny, Miron [University of Wisconsin, Madison (United States); Roy, Alain [University of Wisconsin, Madison (United States); Avery, Paul [University of Florida (United States); Blackburn, Kent [California Institute of Technology (United States); Wenaus, Torre [Brookhaven National Laboratory (United States); Wuerthwein, Frank [University of California, San Diego (United States); Foster, Ian [University of Chicago (United States); Gardner, Rob [University of Chicago (United States); Wilde, Mike [University of Chicago (United States); Blatecky, Alan [Renaissance Computing Institute (United States); McGee, John [Renaissance Computing Institute (United States); Quick, Rob [Indiana University (United States)

    2007-07-15

    The Open Science Grid (OSG) provides a distributed facility where the Consortium members provide guaranteed and opportunistic access to shared computing and storage resources. OSG provides support for and evolution of the infrastructure through activities that cover operations, security, software, troubleshooting, addition of new capabilities, and support for existing and engagement with new communities. The OSG SciDAC-2 project provides specific activities to manage and evolve the distributed infrastructure and support it's use. The innovative aspects of the project are the maintenance and performance of a collaborative (shared and common) petascale national facility over tens of autonomous computing sites, for many hundreds of users, transferring terabytes of data a day, executing tens of thousands of jobs a day, and providing robust and usable resources for scientific groups of all types and sizes. More information can be found at the OSG web site: www.opensciencegrid.org.

  14. GRID INFORMATION SECURITY FUNCTIONAL REQUIREMENT

    Directory of Open Access Journals (Sweden)

    Amy Poh Ai Ling

    2011-07-01

    Full Text Available This paper describes the background of smart information infrastructure and the needs for smart grid information security. It introduces the conceptual analysis to the methodology with the application ofhermeneutic circle and information security functional requirement identification. Information security for the grid market cover matters includes automation and communications industry that affects the operation of electric power systems and the functioning of the utilities that manage them and its awareness of this information infrastructure has become critical to the reliability of the power system. Community benefits from of cost savings, flexibility and deployment along with the establishment of wireless communications. However, concern revolves around the security protections for easily accessible devices such as the smart meter and the related communications hardware. On the other hand, the changing points between traditional versus smart grid networking trend and the information security importance on the communication field reflects the criticality of grid information security functional requirement identification. The goal of this paper is to identify the functional requirement and relate its significance addresses to the consumer requirement of an information security of a smart grid. Vulnerabilities may bring forth possibility for an attacker to penetrate a network, make headway admission to control software, alter it to load conditions that destabilize the grid in unpredictable ways. Focusing on the grid information security functional requirement is stepping ahead in developing consumer trust and satisfaction towardsmart grid completeness.

  15. Monitoring of Grid scientific workflows

    NARCIS (Netherlands)

    B. Balis; M. Bubak; B. Łabno

    2008-01-01

    Scientific workflows are a means of conducting in silico experiments in modern computing infrastructures for e-Science, often built on top of Grids. Monitoring of Grid scientific workflows is essential not only for performance analysis but also to collect provenance data and gather feedback useful i

  16. Astro-WISE and Grid

    NARCIS (Netherlands)

    Begeman, Kor; Belikov, Andrey N.; Dijkstra, Fokke; Meyer-Zhao, Zheng; Valentijn, Edwin A.; Vriend, Willem-Jan

    2013-01-01

    The paper reviews the Astro-WISE infrastructure and demonstrates that the Astro-WISE Information System provides a Grid itself. We describe the integration of Astro-WISE with an external Grid infrastructure (BiGGrid). The integration is performed on all infrastructural layers (data storage, metadata

  17. Smart Grid Control and Communication

    DEFF Research Database (Denmark)

    Ciontea, Catalin-Iosif; Pedersen, Rasmus; Kristensen, Thomas le Fevre;

    2015-01-01

    ) and the quality of the power may become costly. In this light, Smart Grids may provide an answer towards a more active and efficient electrical network. The EU project SmartC2Net aims to enable smart grid operations over imperfect, heterogeneous general purpose networks, which poses a significant challenge...... to the reliability due to the stochastic behavior found in such networks. Therefore, key concepts are presented in this paper targeting the support of proper smart grid control in these network environments and its Real-Time Hardware-In-the Loop (HIL) verification. An overview on the required Information......The expected growth in distributed generation will significantly affect the operation and control of today's distribution grids. Being confronted with fast fluctuating power from distributed generations, the assurance of a reliable service (grid stability, avoidance of energy losses...

  18. 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...

  19. 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).

  20. The smart grid research network

    DEFF Research Database (Denmark)

    Troi, Anders; Jørgensen, Bo Nørregaard; Larsen, Emil Mahler;

    2013-01-01

    This road map is a result of part-recommendation no. 25 in ‘MAIN REPORT – The Smart Grid Network’s recommendations’, written by the Smart Grid Network for the Danish Ministry of Climate, Energy and Building in October 2011. This part-recommendation states: “Part-recommendation 25 – A road map......-recommendation: Universities, along with relevant electric-industry actors, should establish a working group for the completion of a consolidated road map by the end of 2012.” In its work on this report, the Smart Grid Research Network has focused particularly on part-recommendations 26, 27 and 28 in ‘MAIN REPORT – The Smart...... Grid Network’s recommendations’, which relate to strengthening and marketing the research infrastructure that will position Denmark as the global hub for Smart Grid development; strengthening basic research into the complex relationships in electric systems with large quantities of independent parties...

  1. CMS Requirements for the Grid

    Institute of Scientific and Technical Information of China (English)

    K.Holtman; J.Amundson; 等

    2001-01-01

    CMS physicists need to seamlessly access their experimental data and results,independent of location and storage medium,in order to focus on the exploration for the new physics signals arther than the complexities of worldwide data management .In order to achieve this goal,CMS has adopted a tiered worldwide computing model which will incorporate emerging Grid technology.CMS has started to use Grid tools for data processing,replication and migration,Important Grid components are expected to be delivered by the Data Grid projects.like projects,CMS has created a set of long-term requirements to the Grid projects.These requirements are presented and discussed.

  2. An Even Grid Based Lattice Vector Quantization Algorithm for Mobile Audio Coding

    Directory of Open Access Journals (Sweden)

    Bo Hang

    2011-06-01

    Full Text Available This paper proposed an even grid based lattice vector quantization method for audio coding. The method uses energy priority, with basic code book and the ball-type expansion, which is applicable to the low rate of the variable-rate vector quantization coding. The method uses the lattice characteristics to resolve rapid index distribution problem, as well as the compression of the basic code book. The experiment results show that the proposed method is as good as vector quantization method in ITU-T standard G729.1 in quality, with lower storage cost and computational complexity.

  3. The Dual Functionals for the Generalized Ball Basis of Wang-Said Type and Basis Transformation Formulas

    Institute of Scientific and Technical Information of China (English)

    Ping Jiang; Hongyi Wu; Jieqing Tan

    2006-01-01

    The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out.

  4. From the Grid to the Smart Grid, Topologically

    CERN Document Server

    Pagani, Giuliano Andrea

    2013-01-01

    The Smart Grid is not just about the digitalization of the Power Grid. In its more visionary acceptation, it 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 updated? 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 have analyzed samples of the Dutch Distribution Grid in our previous work and we have considered possible evolutions of these using synthetic topologies modeled after studies of complex systems in other technological domains in another previous work. In this paper, we take an extra important further step by defining a methodology for evolving any existing physical Power Grid to a good Smart Grid model th...

  5. Coefficient of restitution of sports balls: A normal drop test

    International Nuclear Information System (INIS)

    Dynamic behaviour of bodies during impact is investigated through impact experiment, the simplest being a normal drop test. Normally, a drop test impact experiment involves measurement of kinematic data; this includes measurement of incident and rebound velocity in order to calculate a coefficient of restitution (COR). A high speed video camera is employed for measuring the kinematic data where speed is calculated from displacement of the bodies. Alternatively, sensors can be employed to measure speeds, especially for a normal impact where there is no spin of the bodies. This paper compares experimental coefficients of restitution (COR) for various sports balls, namely golf, table tennis, hockey and cricket. The energy loss in term of measured COR and effects of target plate are discussed in relation to the material and construction of these sports balls.

  6. Generalized isoperimetric inequalities for extrinsic balls in minimal submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, Vicente

    2002-01-01

    The volume of an extrinsic ball in a minimal submanifold has a well defined lower bound when the ambient manifold has an upper bound on its sectional curvatures, see e.g. [2] and [10]. When this upper bound is non-positive, the second named author has shown an isoperimetric inequality for such do......The volume of an extrinsic ball in a minimal submanifold has a well defined lower bound when the ambient manifold has an upper bound on its sectional curvatures, see e.g. [2] and [10]. When this upper bound is non-positive, the second named author has shown an isoperimetric inequality...... for such domains, see [11]. This result again gives the comparison result for volumes alluded to above together with a characterization of the totally geodesic submanifolds of hyperbolic space forms. In the present paper we find a corresponding sharp isoperimetric inequality for minimal submanifolds in spaces...

  7. VOLUME DEFECT FATIGUE FAILURE OF CERAMIC BALLS UNDER ROLLING CONDITION

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jingling; WU Guoqing; CHEN Xiaoyang

    2007-01-01

    A newly developed pure rolling fatigue test rig with three contact points is used to test the rolling contact fatigue properties of silicon nitride ceramic balls. Ball surfaces are examined after failure with optical microscopy and scanning electron microscopy. The failure cause, fatigue phenomenon and mechanics are analyzed. The research shows that subsurface cracks play a dominant role in the formation of spalling failure. These cracks originated from volume defects of the material and propagate, to form elliptical fatigue spalls under the action of principal tensile stresses. The principal tensile stress increases with increasing contact load, causing spall formation and reduction of rolling contact life. The greater the principal tensile stress is, the more severe the peeling of near surface is. Under the same condition, the closer volume defects are to the surface, the more likely failure occurs, the shorter the rolling contact life is.

  8. Sports injuries in adolescents' ball games: soccer, handball and basketball.

    Science.gov (United States)

    Yde, J; Nielsen, A B

    1990-03-01

    In a prospective study of 302 adolescent players in three ball games (soccer, handball and basketball), 119 incurred injuries. The injury incidence (number of injuries per 1000 playing hours) was 5.6 in soccer, 4.1 in handball and 3.0 in basketball. Ankle sprains accounted for 25 per cent of the injuries, finger sprains 32 per cent, strains in the thigh and leg 10 per cent, and tendinitis/apophysitis 12 per cent. The most serious injuries were four fractures, one anterior cruciate ligament rupture, and two meniscus lesions. The most serious injuries, with the longest rehabilitation period, occurred in soccer. In soccer, many injuries occurred during tackling and contact with an opposing player, while the injuries in handball and basketball were often caused by ball contact and running. PMID:2350669

  9. Slepian Spatial-Spectral Concentration on the Ball

    CERN Document Server

    Khalid, Zubair; McEwen, Jason D

    2014-01-01

    We formulate and solve the Slepian spatial-spectral concentration problem on the three-dimensional ball. Both the standard Fourier-Bessel and also the Fourier-Laguerre spectral domains are considered since the latter exhibits a number of practical advantages (spectral decoupling and exact computation). The Slepian spatial and spectral concentration problems are formulated as eigenvalue problems, the eigenfunctions of which form an orthogonal family of concentrated functions. Equivalence between the spatial and spectral problems is shown. The spherical Shannon number on the ball is derived, which acts as the analog of the space-bandwidth product in the Euclidean setting, giving an estimate of the number of concentrated eigenfunctions and thus the dimension of the space of functions that can be concentrated in both the spatial and spectral domains simultaneously. Various symmetries of the spatial region are considered that reduce considerably the computational burden of recovering eigenfunctions, either by deco...

  10. Sir Robert Ball: Victorian Astronomer and Lecturer par excellence

    Science.gov (United States)

    Jones, R. I. G.

    2005-12-01

    Between 1875 and 1910 Sir Robert Stawell Ball gave an estimated 2,500 lectures in towns and cities all over the British Isles and abroad. This paper traces his lecturing career from its beginnings in Ireland to the triumphs of the Royal Institution, and on lecture tours in the United States of America. After a period in mathematics and mechanics, he became a populariser of science, especially astronomy, and found fame and fortune among the working classes and the aristocracy. What motivated him to tireless travels is uncertain, but it might have been that it was rewarding, financially and to his reputation. Whatever his motives, contemporary accounts are clear that BallÕs lectures were extremely popular and well-received.

  11. Entanglement and the three-dimensionality of the Bloch ball

    Energy Technology Data Exchange (ETDEWEB)

    Masanes, Ll., E-mail: ll.masanes@gmail.com [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Müller, M. P. [Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 19, D-69120 Heidelberg (Germany); Pérez-García, D. [Departamento de Analisis Matematico and IMI, Universidad Complutense de Madrid, 28040 Madrid (Spain); Augusiak, R. [ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels, Barcelona (Spain)

    2014-12-15

    We consider a very natural generalization of quantum theory by letting the dimension of the Bloch ball be not necessarily three. We analyze bipartite state spaces where each of the components has a d-dimensional Euclidean ball as state space. In addition to this, we impose two very natural assumptions: the continuity and reversibility of dynamics and the possibility of characterizing bipartite states by local measurements. We classify all these bipartite state spaces and prove that, except for the quantum two-qubit state space, none of them contains entangled states. Equivalently, in any of these non-quantum theories, interacting dynamics is impossible. This result reveals that “existence of entanglement” is the requirement with minimal logical content which singles out quantum theory from our family of theories.

  12. Sensing and Measurement Architecture for Grid Modernization

    Energy Technology Data Exchange (ETDEWEB)

    Taft, Jeffrey D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); De Martini, Paul [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2016-02-01

    This paper addresses architecture for grid sensor networks, with primary emphasis on distribution grids. It describes a forward-looking view of sensor network architecture for advanced distribution grids, and discusses key regulatory, financial, and planning issues.

  13. BSCW Unstructured Grids - VGRID software FINAL

    Data.gov (United States)

    National Aeronautics and Space Administration — These grids were constructed using VGRID software from NASA Langley. The grids designed for node based (labeled 'nc') and cell-centered solvers are supplied. Grids...

  14. Ball-thrower's fracture of the humerus

    Energy Technology Data Exchange (ETDEWEB)

    Callaghan, Eric B.; Bennett, D. Lee; El-Khoury, Georges Y.; Ohashi, Kenjirou [Department of Radiology, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, IA 52242, Iowa City (United States)

    2004-06-01

    A relatively rare case of ball-thrower's fracture of the humerus is presented. Severe muscular action is an uncommon cause of humeral fractures but has been well documented in the orthopedic literature. To our knowledge, this fracture has not been described in the radiology literature, and awareness of this entity could preclude further unnecessary workup. The mechanism of injury and its typical radiographic appearance is described. (orig.)

  15. Casimir Energy and Vacua vor Superconducting Ball in Supergravity

    CERN Document Server

    Burinskii, A

    2002-01-01

    Casimir energy for solid conducting ball is considered on the base of some finite models. One model is physical and built of a battery of parallel metallic plates. Two finite models are based on the Higgs model of superconductivity. One of them is supersymmetric and based on the Witten field model for superconducting strings. Treatment shows that contribution of Casimir energy can be very essential for superdence state in the neutron stars and nuclear matter.

  16. First results from the Crystal Ball at DORIS II

    International Nuclear Information System (INIS)

    The Crystal Ball has been installed at DORIS II and taking data since the fall of 1982. Data have been obtained at the Y(1S), Y(2S) and the continuum region just below the Y(2S). Preliminary results of the analyses of these data are presented. These results include inclusive photon spectra from the Y(1S) and Y(2S) and the transitions Y' -> π0π0Y and Y' -> γγY. (orig.)

  17. Charged particle identification with modules of the plastic ball

    Energy Technology Data Exchange (ETDEWEB)

    Gutbrod, H.H.; Maier, M.R.; Ritter, H.G.; Warwick, A.I.; Weik, F.; Wieman, H.; Wolf, K.L.

    1980-10-01

    The low energy pion channel (LEP) at LAMPF was used to calibrate the response of modules of the Plastic Ball detector for positive pions and protons. The detection efficiency was measured at various energies. The resolution and efficiency were found to be independent of the point at which the particle entered the detector. Scattered out particles could be well detected by including neighbouring detectors in the analysis.

  18. Functional macroscopic behavior of weighted random ball model

    OpenAIRE

    Breton, Jean-Christophe; Dombry, Clement

    2010-01-01

    We consider a generalization of the weighted random ball model. The model is driven by a random Poisson measure with a product heavy tailed intensity measure. Such a model typically represents the transmission of a network of stations with a fading effect. In a previous article, the authors proved the convergence of the finite-dimensional distributions of related generalized random fields under various scalings and in the particular case when the fading function is the indicator function of t...

  19. Oscillation and levitation of balls in continuously stratified fluids

    OpenAIRE

    Biro, I.; Gyure, B.; I. M. Janosi; Szabo, K. G.; Tel, T.

    2007-01-01

    The free motion of balls is investigated experimentally in continously stratified fluid in a finite container. The oscillation frequency is found to be very close to the local Brunt-Vaisala frequency. The effect of added mass proves to be practically negligible. The evolution of rear jets is demonstrated, and a kind of long term levitation is found. We show that the classical viscous drag would lead to a much stronger damping than observed in the experiment. This is interpreted as a consequen...

  20. The Utilization of Carp (Cyprinus carpio) Flesh as Fish Ball

    OpenAIRE

    YANAR, Yasemen

    1999-01-01

    In this study, the sensory properties and shelf life of fish balls prepared from carp flesh were investigated. Four study groups were prepared with different combinations of ingredients: garlic, garlic-sunflower oil, onion and onion-sunflower oil. A control group was also prepared. At the end of the sensory evaluation, the groups received between 7.4 and 9.07 points from the panelists regarding appearance, texture, succulence, odour and flavour and general acceptance. The onion and garlic ...

  1. GYROLESS BALL: ESTIMATION OF ANGULAR VELOCITY WITHOUT GYROSCOPE

    OpenAIRE

    Magnis, L; Petit, Nicolas

    2015-01-01

    In [MP15a, MP15b], an algorithm is proposed to estimate the angular velocity of a rigid body using only vector measurements (i.e. measurements of unknown but constant directions). The cases of a single and two vectors measurements have been addressed using similarly structured state-observers. In this note, we report experiments conducted on one such rigid body, here a wood ball, which is equipped with a smartphone. The direction sensors of the smartphone (magnetometer and accelerometer) are ...

  2. Simulation of distribution of radiation energy density in water balls

    Institute of Scientific and Technical Information of China (English)

    TANG Shi-Biao; MA Qing-Li; YIN Ze-Jie; TANG Yu; HUANG Huan; RAO Nan-Xia; ZHU Da-Ming

    2005-01-01

    The distribution of energy deposition density in radiate region and its surrounding areas from γ-rays was simulated and analyzed for a water-ball model with Geant4 package ( Geant4.7.0,2005 ) developed by CERN (the Center of European Research of Nucleus). The results show that the distribution depends strongly on the collimating condition of radiation beam. A well-collimated beam would reduce radiation effects on surrounding areas.

  3. Tracking a table tennis ball for umpiring purposes

    OpenAIRE

    Myint, Hnin; Wong, Patrick; Dooley, Laurence; Hopgood, Adrian

    2015-01-01

    This study investigates tracking a table-tennis ball rapidly from video captured using low-cost equipment for umpiring purposes. A number of highly efficient algorithms have been developed for this purpose. The proposed system was tested using sequences capture from real match scenes. The preliminary results of experiments show that accurate and rapid tracking can be achieved even under challenging conditions, including occlusion and colour merging. This work can contribute to the development...

  4. On electromagnetic models of ball lightning with topological structure

    OpenAIRE

    Donoso, J. M.; Fernandez-Ranada, A.; Trueba, J. L.

    2003-01-01

    It has been long admitted that a consequence of the virial theorem is that there can be no equilibrium configurations of a system of charges in electromagnetic interaction in the absence of external forces. However, recent results have shown that the virial theorem can not preclude the existence of certain nontrivial equilibrium configurations. Although some of these new results are based on an effective microscopic field theory, they are important for a theory of ball lightning that has been...

  5. 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

  6. Grid Integration Studies: Data Requirements, Greening the Grid

    Energy Technology Data Exchange (ETDEWEB)

    Katz, Jessica

    2015-06-01

    A grid integration study is an analytical framework used to evaluate a power system with high penetration levels of variable renewable energy (VRE). A grid integration study simulates the operation of the power system under different VRE scenarios, identifying reliability constraints and evaluating the cost of actions to alleviate those constraints. These VRE scenarios establish where, how much, and over what timeframe to build generation and transmission capacity, ideally capturing the spatial diversity benefits of wind and solar resources. The results help build confidence among policymakers, system operators, and investors to move forward with plans to increase the amount of VRE on the grid.

  7. A facile strategy for rapid preparation of graphene spongy balls

    Science.gov (United States)

    Wan, Shu; Bi, Hengchang; Xie, Xiao; Su, Shi; Du, Kai; Jia, Haiyang; Xu, Tao; He, Longbing; Yin, Kuibo; Sun, Litao

    2016-01-01

    Porous three dimensional (3D) graphene macrostructures have demonstrated the potential in versatile applications in recent years, including energy storage, sensors, and environment protection, etc. However, great research attention has been focused on the optimization of the structure and properties of graphene-based materials. Comparatively, there are less reports on how to shape 3D graphene macrostructures rapidly and effortlessly, which is critical for mass production in industry. Here, we introduce a facile and efficient method, low temperature frying to form graphene-based spongy balls in liquid nitrogen with a yield of ~400 balls min−1. Moreover, the fabrication process can be easily accelerated by using multi pipettes working at the same time. The graphene spongy balls show energy storage with a specific capacitance of 124 F g−1 and oil adsorbing with a capacity of 105.4 times its own weight. This strategy can be a feasible approach to overcome the low efficiency in production and speed up the development of porous 3D graphene-based macrostructures in industrial applications. PMID:27586559

  8. Experimental and theoretical study of phase transitions under ball milling

    International Nuclear Information System (INIS)

    The aim of this work was to determine how phase transition s under ball-milling depend on the milling conditions and to find out if one can rationalize such transitions with the theory of driven alloys. We have chosen two phase transitions: the order-disorder transition in Fe Al and the precipitation-dissolution NiGe. In the case of Fe Al we have found that the steady-state long range order parameter achieved under ball milling intensity; moreover the same degree of order is achieved starting from an ordered alloy or a disordered solid solution. On the way to fully disordered state the degree of order either decreases monotonically or goes through a short lived transient state. This behaviour is reminiscent of a first order transition while the equilibrium transition is second order. All the above features are well reproduced by a simple model of driven alloys, which was originally build for alloys under irradiation. The stationary degree of order results of two competitive atomic jump mechanisms: the forced displacements induced by the shearing of the grains, and the thermally activated jumps caused by vacancies migrations. Finally we have performed atomistic simulations with a Monte Carlo kinetic algorithm, which revealed the role of the fluctuations in the intensity of the forcing. Moreover we have shown that specific atomistic mechanisms are active in a dilute NiGe solid solution which might lead to ball milling induced precipitation in under-saturated solid solution. (author)

  9. A facile strategy for rapid preparation of graphene spongy balls

    Science.gov (United States)

    Wan, Shu; Bi, Hengchang; Xie, Xiao; Su, Shi; Du, Kai; Jia, Haiyang; Xu, Tao; He, Longbing; Yin, Kuibo; Sun, Litao

    2016-09-01

    Porous three dimensional (3D) graphene macrostructures have demonstrated the potential in versatile applications in recent years, including energy storage, sensors, and environment protection, etc. However, great research attention has been focused on the optimization of the structure and properties of graphene-based materials. Comparatively, there are less reports on how to shape 3D graphene macrostructures rapidly and effortlessly, which is critical for mass production in industry. Here, we introduce a facile and efficient method, low temperature frying to form graphene-based spongy balls in liquid nitrogen with a yield of ~400 balls min‑1. Moreover, the fabrication process can be easily accelerated by using multi pipettes working at the same time. The graphene spongy balls show energy storage with a specific capacitance of 124 F g‑1 and oil adsorbing with a capacity of 105.4 times its own weight. This strategy can be a feasible approach to overcome the low efficiency in production and speed up the development of porous 3D graphene-based macrostructures in industrial applications.

  10. A facile strategy for rapid preparation of graphene spongy balls.

    Science.gov (United States)

    Wan, Shu; Bi, Hengchang; Xie, Xiao; Su, Shi; Du, Kai; Jia, Haiyang; Xu, Tao; He, Longbing; Yin, Kuibo; Sun, Litao

    2016-01-01

    Porous three dimensional (3D) graphene macrostructures have demonstrated the potential in versatile applications in recent years, including energy storage, sensors, and environment protection, etc. However, great research attention has been focused on the optimization of the structure and properties of graphene-based materials. Comparatively, there are less reports on how to shape 3D graphene macrostructures rapidly and effortlessly, which is critical for mass production in industry. Here, we introduce a facile and efficient method, low temperature frying to form graphene-based spongy balls in liquid nitrogen with a yield of ~400 balls min(-1). Moreover, the fabrication process can be easily accelerated by using multi pipettes working at the same time. The graphene spongy balls show energy storage with a specific capacitance of 124 F g(-1) and oil adsorbing with a capacity of 105.4 times its own weight. This strategy can be a feasible approach to overcome the low efficiency in production and speed up the development of porous 3D graphene-based macrostructures in industrial applications. PMID:27586559

  11. Surface Integrity of Inconel 718 by Ball Burnishing

    Science.gov (United States)

    Sequera, A.; Fu, C. H.; Guo, Y. B.; Wei, X. T.

    2014-09-01

    Inconel 718 has wide applications in manufacturing mechanical components such as turbine blades, turbocharger rotors, and nuclear reactors. Since these components are subject to harsh environments such as high temperature, pressure, and corrosion, it is critical to improve the functionality to prevent catastrophic failure due to fatigue or corrosion. Ball burnishing as a low plastic deformation process is a promising technique to enhance surface integrity for increasing component fatigue and corrosion resistance in service. This study focuses on the experimental study on surface integrity of burnished Inconel 718. The effects of burnishing ball size and pressure on surface integrity factors such as surface topography, roughness, and hardness are investigated. The burnished surfaces are smoother than the as-machined ones. Surface hardness after burnishing is higher than the as-machined surfaces, but become stable over a certain burnishing pressure. There exists an optimal process space of ball sized and burnishing pressure for surface finish. In addition, surface hardness after burnishing is higher than the as-machined surfaces, which is confirmed by statistical analysis.

  12. Axiom turkey genotyping array

    Science.gov (United States)

    The Axiom®Turkey Genotyping Array interrogates 643,845 probesets on the array, covering 643,845 SNPs. The array development was led by Dr. Julie Long of the USDA-ARS Beltsville Agricultural Research Center under a public-private partnership with Hendrix Genetics, Aviagen, and Affymetrix. The Turk...

  13. National Smart Water Grid

    Energy Technology Data Exchange (ETDEWEB)

    Beaulieu, R A

    2009-07-13

    The United States repeatedly experiences floods along the Midwest's large rivers and droughts in the arid Western States that cause traumatic environmental conditions with huge economic impact. With an integrated approach and solution these problems can be alleviated. Tapping into the Mississippi River and its tributaries, the world's third largest fresh water river system, during flood events will mitigate the damage of flooding and provide a new source of fresh water to the Western States. The trend of increased flooding on the Midwest's large rivers is supported by a growing body of scientific literature. The Colorado River Basin and the western states are experiencing a protracted multi-year drought. Fresh water can be pumped via pipelines from areas of overabundance/flood to areas of drought or high demand. Calculations document 10 to 60 million acre-feet (maf) of fresh water per flood event can be captured from the Midwest's Rivers and pumped via pipelines to the Colorado River and introduced upstream of Lake Powell, Utah, to destinations near Denver, Colorado, and used in areas along the pipelines. Water users of the Colorado River include the cities in southern Nevada, southern California, northern Arizona, Colorado, Utah, Indian Tribes, and Mexico. The proposed start and end points, and routes of the pipelines are documented, including information on right-of-ways necessary for state and federal permits. A National Smart Water Grid{trademark} (NSWG) Project will create thousands of new jobs for construction, operation, and maintenance and save billions in drought and flood damage reparations tax dollars. The socio-economic benefits of NWSG include decreased flooding in the Midwest; increased agriculture, and recreation and tourism; improved national security, transportation, and fishery and wildlife habitats; mitigated regional climate change and global warming such as increased carbon capture; decreased salinity in Colorado River water

  14. First scientific results from the Estonian Grid

    CERN Document Server

    Hektor, A; Kadastik, M; Skaburskas, K; Teder, H; Hektor, Andi; Anton, Lauri; Kadastik, Mario; Skaburskas, Konstantin; Teder, Hardi

    2004-01-01

    We present first scientific results, technical details and recent developments in the Estonian Grid. Ideas and concepts behind Grid technology are described. We mention some most crucial parts of a Grid system, as well as some unique possibilities in the Estonian situation. Scientific applications currently running on Estonian Grid are listed. We discuss the first scientific computations and results the Estonian Grid. The computations show that the middleware is well chosen and the Estonian Grid has remarkable stability and scalability. The authors present the collected results and experiences of the development of the Estonian Grid and add some ideas of the near future of the Estonian Grid.

  15. An electrostatic analog for generating cascade grids

    Science.gov (United States)

    Adamczyk, J. J.

    1980-01-01

    Accurate and efficient numerical simulation of flows through turbomachinery blade rows depends on the topology of the computational grids. These grids must reflect the periodic nature of turbomachinery blade row geometries and conform to the blade shapes. Three types of grids can be generated that meet these minimal requirements: through-flow grids, O-type grids, and C-type grids. A procedure which can be used to generate all three types of grids is presented. The resulting grids are orthogonal and can be stretched to capture the essential physics of the flow. A discussion is also presented detailing the extension of the generation procedure to three dimensional geometries.

  16. Energy Conservation In Computational Grids

    Directory of Open Access Journals (Sweden)

    Monika Yadav

    2012-07-01

    Full Text Available With the increasing development of high-speed wide-area networks and powerful though low cost computational resources, grid computing has emerged as an attractive computing paradigm.With recent advances in computing, the scope of grid computing has been expanded to include mobile and pervasive devices. Grids have become one of the highest consumers of energy. High performance computing is achieved at the cost of energy consumption. Increasing the performance of computer systems requires increasing number of resources which leads to higher power consumption and it creates negative impact on environment. Idle sites in grid are direct sources of energy waste. Saving energy causes twodirect advantages: financial and environmental cost reduction and sustainability. With the Grid becoming a viable high-performance alternative to the traditional supercomputing environment, various aspects of Grid resource utilization which can help in energy conservation are gaining significance. In this paper we explore the possibility of reduction in energy consumption of a grid of heterogeneous computers by making use of different power states of cpu.

  17. Constructing the ASCI computational grid

    Energy Technology Data Exchange (ETDEWEB)

    BEIRIGER,JUDY I.; BIVENS,HUGH P.; HUMPHREYS,STEVEN L.; JOHNSON,WILBUR R.; RHEA,RONALD E.

    2000-06-01

    The Accelerated Strategic Computing Initiative (ASCI) computational grid is being constructed to interconnect the high performance computing resources of the nuclear weapons complex. The grid will simplify access to the diverse computing, storage, network, and visualization resources, and will enable the coordinated use of shared resources regardless of location. To match existing hardware platforms, required security services, and current simulation practices, the Globus MetaComputing Toolkit was selected to provide core grid services. The ASCI grid extends Globus functionality by operating as an independent grid, incorporating Kerberos-based security, interfacing to Sandia's Cplant{trademark},and extending job monitoring services. To fully meet ASCI's needs, the architecture layers distributed work management and criteria-driven resource selection services on top of Globus. These services simplify the grid interface by allowing users to simply request ''run code X anywhere''. This paper describes the initial design and prototype of the ASCI grid.

  18. Visualization of air flow around soccer ball using a particle image velocimetry.

    Science.gov (United States)

    Hong, Sungchan; Asai, Takeshi; Seo, Kazuya

    2015-10-08

    A traditional soccer ball is constructed using 32 pentagonal and hexagonal panels. In recent years, however, the likes of the Teamgeist and Jabulani balls, constructed from 14 and 8 panels, respectively, have entered the field, marking a significant departure from conventionality in terms of shape and design. Moreover, the recently introduced Brazuca ball features a new 6-panel design and has already been adopted by many soccer leagues. However, the shapes of the constituent panels of these balls differ substantially from those of conventional balls. Therefore, this study set out to investigate the flight and aerodynamic characteristics of different orientations of the soccer ball, which is constructed from panels of different shapes. A wind tunnel test showed substantial differences in the aerodynamic forces acting on the ball, depending on its orientation. Substantial differences were also observed in the aerodynamic forces acting on the ball in different directions, corresponding to its orientation and rotation. Moreover, two-dimensional particle image velocimetry (2D-PIV) measurements showed that the boundary separation varies depending on the orientation of the ball. Based on these results, we can conclude that the shape of the panels of a soccer ball substantially affects its flight trajectory.

  19. Preparation of High Performance Green Alumina Ceramic Balls by Roller Production Waste

    Institute of Scientific and Technical Information of China (English)

    ZHONG Lianyun; WU Bolin; ZHANG Lianmeng; ZHANG Guifang

    2008-01-01

    To reuse roller waste as a raw material of high performance green ceramic balls,three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with90% Al2O3 were prepared,and the Al2O3 content of the prepared balls was 75%.It is found that the effect of calcia and magnesia on the wear resistance of ceramic balls is contrast to the accepted one: the wear rate of the ceramic balls prepared in CaO-Al2O3-SiO2 system is the lowest and the wear rate of the ceramic balls prepared in MgO-Al2O3-SiO2 is the highest.The main crystal phase of the ceramic ball is mullite and corundum.The ceramic ball granular is uniform and fine with 4-5 um average size.The pore diameter is about 2 um.The wear way of the ceramic balls is mainly transcrystalline fracture.

  20. 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.

  1. The Grid Resource Broker, A Ubiquitous Grid Computing Framework

    Directory of Open Access Journals (Sweden)

    Giovanni Aloisio

    2002-01-01

    Full Text Available Portals to computational/data grids provide the scientific community with a friendly environment in order to solve large-scale computational problems. The Grid Resource Broker (GRB is a grid portal that allows trusted users to create and handle computational/data grids on the fly exploiting a simple and friendly web-based GUI. GRB provides location-transparent secure access to Globus services, automatic discovery of resources matching the user's criteria, selection and scheduling on behalf of the user. Moreover, users are not required to learn Globus and they do not need to write specialized code or to rewrite their existing legacy codes. We describe GRB architecture, its components and current GRB features addressing the main differences between our approach and related work in the area.

  2. Buildings-to-Grid Technical Opportunities: From the Grid Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kropski, Ben [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pratt, Rob [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-03-28

    This paper outlines the nature of the power grid, lists challenges and barriers to the implementation of a transactive energy ecosystem, and provides concept solutions to current technological impediments.

  3. Secondary emission monitor (SEM) grids.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    A great variety of Secondary Emission Monitors (SEM) are used all over the PS Complex. At other accelerators they are also called wire-grids, harps, etc. They are used to measure beam density profiles (from which beam size and emittance can be derived) in single-pass locations (not on circulating beams). Top left: two individual wire-planes. Top right: a combination of a horizontal and a vertical wire plane. Bottom left: a ribbon grid in its frame, with connecting wires. Bottom right: a SEM-grid with its insertion/retraction mechanism.

  4. Hierarchical Control for Smart Grids

    DEFF Research Database (Denmark)

    Trangbæk, K; Bendtsen, Jan Dimon; Stoustrup, Jakob

    2011-01-01

    This paper deals with hierarchical model predictive control (MPC) of smart grid systems. The design consists of a high level MPC controller, a second level of so-called aggregators, which reduces the computational and communication-related load on the high-level control, and a lower level...... of autonomous consumers. The control system is tasked with balancing electric power production and consumption within the smart grid, and makes active use of the flexibility of a large number of power producing and/or power consuming units. The objective is to accommodate the load variation on the grid, arising...

  5. SDPG: Spatial Data Processing Grid

    Institute of Scientific and Technical Information of China (English)

    XIAO Nong(肖侬); FUV Wei(付伟)

    2003-01-01

    Spatial applications will gain high complexity as the volume of spatial data increases rapidly. A suitable data processing and computing infrastructure for spatial applications needs to be established. Over the past decade, grid has become a powerful computing environment for data intensive and computing intensive applications. Integrating grid computing with spatial data processing technology, the authors designed a spatial data processing grid (called SDPG) to address the related problems. Requirements of spatial applications are examined and the architecture of SDPG is described in this paper. Key technologies for implementing SDPG are discussed with emphasis.

  6. National transmission grid study

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Spencer [USDOE Office of the Secretary of Energy, Washington, DC (United States)

    2003-05-31

    The National Energy Policy Plan directed the U.S. Department of Energy (DOE) to conduct a study to examine the benefits of establishing a national electricity transmission grid and to identify transmission bottlenecks and measures to address them. DOE began by conducting an independent analysis of U.S. electricity markets and identifying transmission system bottlenecks using DOE’s Policy Office Electricity Modeling System (POEMS). DOE’s analysis, presented in Section 2, confirms the central role of the nation’s transmission system in lowering costs to consumers through increased trade. More importantly, DOE’s analysis also confirms the results of previous studies, which show that transmission bottlenecks and related transmission system market practices are adding hundreds of millions of dollars to consumers’ electricity bills each year. A more detailed technical overview of the use of POEMS is provided in Appendix A. DOE led an extensive, open, public input process and heard a wide range of comments and recommendations that have all been considered.1 More than 150 participants registered for three public workshops held in Detroit, MI (September 24, 2001); Atlanta, GA (September 26, 2001); and Phoenix, AZ (September 28, 2001).

  7. 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)

  8. Grid line artifact formation: A comprehensive theory

    International Nuclear Information System (INIS)

    Linear focused grids are commonly used in general radiography and mammography to control scatter. In these applications, if lines would be visible when the grid was stationary, then the grid is moved during the x-ray exposure to blur out grid lines. Presented is a theoretical framework for estimating grid line artifact magnitude and evaluating artifact suppression techniques. The framework takes as parameters the grid pitch, septum thickness, and exposure time, and allows for a variation in grid velocity and in x-ray tube output during the exposure. Grid line artifacts are evaluated for a variety of conditions. These include a stationary grid, a grid moving at a constant velocity with no kV ripple, a grid moving at a constant velocity with large kV ripple, and a grid moving with decreasing velocity and no kV ripple. Also evaluated are grid line artifacts for a novel suppression technique in which the grid moves at a constant velocity and the x-ray exposure waveform is 'feathered', i.e., when the x-ray exposure waveform has a soft start and stop. Of practical interest is that it is possible to effectively eliminate grid line artifacts when the grid moves only a short distance with an appropriately 'feathered' exposure waveform. This capability permits one to design efficient and compact coarse strip density grid systems

  9. Using the LibCF/GRIDSPEC extensions to interpret data on mosaic grids with CDAT

    Science.gov (United States)

    Kindig, D.; Pletzer, A.; Balaji, V.; Hankin, S. C.; Hartnett, E. J.; Doutriaux, C.; Painter, J.; Sobol, A.; Wrobel, M.

    2010-12-01

    Increasingly earth system models perform computations on grids that are not describable as simple, rectangular arrays (e.g. lon by lat), instead requiring a mosaic of interacting, logically rectangular tiles. Such grids are developed for a variety of reasons that include removal of coordinate singularities that may degrade numerical reliability in a region of interest (e.g. the north pole in an ocean model) and increasing the uniformity of numerical precision over the globe. Coupled earth system models, typically characterized by independent coordinate reference systems for modeling atmosphere, ocean, ice, and terrestrial processes, are themselves examples of such mosaic grids. GRIDSPEC is a proposed set of conventions to the Climate and Forecast library (LibCF) describing data on mosaic grids developed by V. Balaji et al. (Geophysical Fluid Dynamics Laboratory). It supports unstructured assemblies of structured grids, including the cubed-sphere and tripolar meshes. Here we review a GRIDSPEC NetCDF format based on host, contact, grid, and data files. We will show how mosaic grids can be created from the ground up using a C API and the Python Climate Data Anaysis Tools (CDAT) for visualization. As an application we use GRIDSPEC to regrid cubed-sphere data onto a longitude-latitude grid.

  10. Cosmological Simulations using Grid Middleware

    CERN Document Server

    Caniou, Y; Depardon, B; Courtois, H; Teyssier, R

    2006-01-01

    One way to access the aggregated power of a collection of heterogeneous machines is to use a grid middleware, such as DIET, GridSolve or NINF. It addresses the problem of monitoring the resources, of handling the submissions of jobs and as an example the inherent transfer of input and output data, in place of the user. In this paper we present how to run cosmological simulations using the RAMSES application along with the DIET middleware. We will describe how to write the corresponding DIET client and server. The remainder of the paper is organized as follows: Section 2 presents the DIET middleware. Section 3 describes the RAMSES cosmological software and simulations, and how to interface it with DIET. We show how to write a client and a server in Section 4. Finally, Section 5 presents the experiments realized on Grid'5000, the French Research Grid, and we conclude in Section 6.

  11. BSCW Unstructured Mixed Element Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — Corase Grid: Quad Surface Faces= 9360 Tria Surface Faces= 128928 Nodes = 2869187 Total Elements = 9099201 Hex Elements = 0 Pent_5 Elements = 0 Pent_6 Elements =...

  12. U.S. Topographic Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — isotop.bin - topographic data for conterminous U.S. projected on an 8 km grid. Projection is Albers, central meridian = 96 degrees West, base latitude = 0 degrees...

  13. Formal Aspects of Grid Brokering

    CERN Document Server

    Kertész, Attila; 10.4204/EPTCS.14.2

    2009-01-01

    Coordination in distributed environments, like Grids, involves selecting the most appropriate services, resources or compositions to carry out the planned activities. Such functionalities appear at various levels of the infrastructure and in various means forming a blurry domain, where it is hard to see how the participating components are related and what their relevant properties are. In this paper we focus on a subset of these problems: resource brokering in Grid middleware. This paper aims at establishing a semantical model for brokering and related activities by defining brokering agents at three levels of the Grid middleware for resource, host and broker selection. The main contribution of this paper is the definition and decomposition of different brokering components in Grids by providing a formal model using Abstract State Machines.

  14. Pub: Grid 2004, 2 signalement

    DEFF Research Database (Denmark)

    2004-01-01

    2. signalement er en af flere manifesteringer omkring det at skabe en tale omkring udfordringer. Pub: Grid 2004 indeholder en række arbejder, der afspejler et fagligt udviklingsarbejde på afdeling 6....

  15. 84-KILOMETER RADIOLOGICAL MONITORING GRID

    International Nuclear Information System (INIS)

    The purpose of this calculation is to document the development of a radial grid that is suitable for evaluating the pathways and potential impacts of a release of radioactive materials to the environment within a distance of 84 kilometers (km). The center of the grid represents an approximate location from which a potential release of radioactive materials could originate. The center is located on Nevada State Plane coordinates Northing 765621.5, and Easting 570433.6, which is on the eastern side of Exile Hill at the Yucca Mountain site. The North Portal Pad is located over this point. The grid resulting from this calculation is intended for use primarily in the Radiological Monitoring Program (RadMP). This grid also is suitable for use in Biosphere Modeling and other Yucca Mountain Site Characteristic Project (YMP) activities that require the evaluation of data referenced by spatial or geographic coordinates

  16. Governments plan data grid projects

    CERN Multimedia

    Thibodeau, Patrick

    2007-01-01

    "Some governments and not-for-profit organizations such as hospitals are beginning to look at data grid technology as a means to improve servies, lower operating costs and spur economic development." (1 page)

  17. Direct writing electrodes using a ball pen for paper-based point-of-care testing.

    Science.gov (United States)

    Li, Zedong; Li, Fei; Hu, Jie; Wee, Wei Hong; Han, Yu Long; Pingguan-Murphy, Belinda; Lu, Tian Jian; Xu, Feng

    2015-08-21

    The integration of paper with an electrochemical device has attracted growing attention for point-of-care testing, where it is of great importance to fabricate electrodes on paper in a low-cost, easy and versatile way. In this work, we report a simple strategy for directly writing electrodes on paper using a pressure-assisted ball pen to form a paper-based electrochemical device (PED). This method is demonstrated to be capable of fabricating electrodes on paper with good electrical conductivity and electrochemical performance, holding great potential to be employed in point-of-care applications, such as in human health diagnostics and food safety detection. As examples, the PEDs fabricated using the developed method are applied for detection of glucose in artificial urine and melamine in sample solutions. Furthermore, our developed strategy is also extended to fabricate PEDs with multi-electrode arrays and write electrodes on non-planar surfaces (e.g., paper cup, human skin), indicating the potential application of our method in other fields, such as fabricating biosensors, paper electronics etc. PMID:26079757

  18. Passive P-control of a grid-connected photovoltaic inverter

    NARCIS (Netherlands)

    Meza, C.; Jeltsema, D.; Scherpen, J. M. A.; Biel, D.

    2008-01-01

    A passive P-controller for a single-phase single-stage grid-connected photovoltaic inverter is presented. Explicit dependance of the PV array parameters on external unpredictable variables such as temperature and solar irradiance is avoided by extending the control scheme with a reference estimator.

  19. Methods for the Optimal Design of Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2011-01-01

    and the efficient processing of this power by the DC/AC inverter. In this paper two new methods are presented for the optimal design of a PV inverter power section, output filter and MPPT control strategy. The influences of the electric grid regulations and standards as well as the PV array operational...

  20. Smart grid applications and developments

    CERN Document Server

    Mah, Daphne; Li, Victor OK; Balme, Richard

    2014-01-01

    Meeting today's energy and climate challenges require not only technological advancement but also a good understanding of stakeholders' perceptions, political sensitivity, well-informed policy analyses and innovative interdisciplinary solutions. This book will fill this gap. This is an interdisciplinary informative book to provide a holistic and integrated understanding of the technology-stakeholder-policy interactions of smart grid technologies. The unique features of the book include the following: (a) interdisciplinary approach - by bringing in the policy dimensions to smart grid technologi