WorldWideScience

Sample records for single-lobed far-field patterns

  1. Confinement factor, near and far field patterns in InGaN MQW laser diodes

    Science.gov (United States)

    Martín, J.; Sánchez, M.

    2005-07-01

    In this work the influence of the QW number in the active region on spectral characteristics in InGaN multi quamtun well lasers is analyzed. A comparison between the abrupt index step structure (Step) and a graded-index structure (GRIN) is done. The effect of the introduction of a p-AlxGa1-xN electron blocking layer, placed above the last InGaN barrier in the Step structure is also analyzed. Calculations of the confinement factor, near and far field patterns were carried out. We found that with the adequate aluminum content in this layer, the confinement factor, near and far field patterns are improved, and values similar to those obtained with GRIN structure can be reached.

  2. EM Modeling of Far-Field Radiation Patterns for Antennas on the GMA-TT UAV

    Science.gov (United States)

    Mackenzie, Anne I.

    2015-01-01

    To optimize communication with the Generic Modular Aircraft T-Tail (GMA-TT) unmanned aerial vehicle (UAV), electromagnetic (EM) simulations have been performed to predict the performance of two antenna types on the aircraft. Simulated far-field radiation patterns tell the amount of power radiated by the antennas and the aircraft together, taking into account blockage by the aircraft as well as radiation by conducting and dielectric portions of the aircraft. With a knowledge of the polarization and distance of the two communicating antennas, e.g. one on the UAV and one on the ground, and the transmitted signal strength, a calculation may be performed to find the strength of the signal travelling from one antenna to the other and to check that the transmitted signal meets the receiver system requirements for the designated range. In order to do this, the antenna frequency and polarization must be known for each antenna, in addition to its design and location. The permittivity, permeability, and geometry of the UAV components must also be known. The full-wave method of moments solution produces the appropriate dBi radiation pattern in which the received signal strength is calculated relative to that of an isotropic radiator.

  3. Analytic models for beam propagation and far-field patterns in slab and bow-tie x-ray lasers

    International Nuclear Information System (INIS)

    Chandler, E.A.

    1994-06-01

    Simplified analytic models for beam propagation in slab and bow-tie x-ray lasers yield convenient expressions that provide both a framework for guidance in computer modeling and useful approximates for experimenters. In unrefracted bow-tie lasers, the laser shape in conjunction with the nearly-exponential weighting of rays according to their length produces a small effective aperture for the signal. We develop an analytic expression for the aperture and the properties of the far-field signal. Similarly, we develop the view that the far-field pattern of refractive slab lasers is the result of effective apertures that are created by the interplay of refraction and exponential amplification. We present expressions for the size of this aperture as a function of laser parameters as well as for the intensity and position of the far-field lineout. This analysis also yields conditions for the refraction limit in slab lasers and an estimate for the signal loss due to refraction

  4. New approach to far field analysis for radiation pattern estimation using FDTD method

    Directory of Open Access Journals (Sweden)

    Nikolić Bojana

    2014-01-01

    Full Text Available In this paper an approach to efficient computation of radiation pattern in FDTD simulation environment is presented. A necessary large distance from the radiating object is achieved by multigrid space discretization with unilaterally connected subdomains. A numerical dispersion is reduced using more general complex-envelope finite difference time domain (CE-FDTD formulation and high order accuracy FDTD schemes where possible. In order to examine how much the introduced algorithm complexity and increased demands concerning computational power and memory are justified by the gain in accuracy, several different scenarios were considered. [Projekat Ministarstva nauke Republike Srbije, br. TR-32051 i br. TR-33008

  5. Method to mosaic gratings that relies on analysis of far-field intensity patterns in two wavelengths

    Science.gov (United States)

    Hu, Yao; Zeng, Lijiang; Li, Lifeng

    2007-01-01

    We propose an experimental method to coherently mosaic two planar diffraction gratings. The method uses a Twyman-Green interferometer to guarantee the planar parallelism of the two sub-aperture gratings, and obtains the in-plane rotational error and the two translational errors from analysis of the far-field diffraction intensity patterns in two alignment wavelengths. We adjust the relative attitude and position of the two sub-aperture gratings to produce Airy disk diffraction patterns in both wavelengths. In our experiment, the repeatability of in-plane rotation adjustment was 2.35 μrad and that of longitudinal adjustment was 0.11 μm. The accuracy of lateral adjustment was about 2.9% of the grating period.

  6. Far field acceleration

    International Nuclear Information System (INIS)

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail

  7. Far-field coupling in nanobeam photonic crystal cavities

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, Ian, E-mail: ian.rousseau@epfl.ch; Sánchez-Arribas, Irene; Carlin, Jean-François; Butté, Raphaël; Grandjean, Nicolas [Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2016-05-16

    We optimized the far-field emission pattern of one-dimensional photonic crystal nanobeams by modulating the nanobeam width, forming a sidewall Bragg cross-grating far-field coupler. By setting the period of the cross-grating to twice the photonic crystal period, we showed using three-dimensional finite-difference time-domain simulations that the intensity extracted to the far-field could be improved by more than three orders of magnitude compared to the unmodified ideal cavity geometry. We then experimentally studied the evolution of the quality factor and far-field intensity as a function of cross-grating coupler amplitude. High quality factor (>4000) blue (λ = 455 nm) nanobeam photonic crystals were fabricated out of GaN thin films on silicon incorporating a single InGaN quantum well gain medium. Micro-photoluminescence spectroscopy of sets of twelve identical nanobeams revealed a nine-fold average increase in integrated far-field emission intensity and no change in average quality factor for the optimized structure compared to the unmodulated reference. These results are useful for research environments and future nanophotonic light-emitting applications where vertical in- and out-coupling of light to nanocavities is required.

  8. Actinide chemistry in the far field

    International Nuclear Information System (INIS)

    Livens, F.R.; Morris, K.; Parkman, R.; Moyes, L.

    1996-01-01

    The environmental chemistry of the actinides is complicated due both to the extensive redox and coordination chemistry of the elements and also to the complexity of the reactive phases encountered in natural environments. In the far field, interactions with reactive surfaces, coatings and colloidal particles will play a crucial role in controlling actinide mobility. By virtue of both their abundance and reactivity; clays and other layer aluminosilicate minerals, hydrous oxides and organic matter (humic substances) are all identified as having the potential to react with actinide ions and some possible modes of interaction are described, together with experimental evidence for their occurrence. (author)

  9. The Far-Field Hubble Constant

    Science.gov (United States)

    Lauer, Tod

    1995-07-01

    We request deep, near-IR (F814W) WFPC2 images of five nearby Brightest Cluster Galaxies (BCG) to calibrate the BCG Hubble diagram by the Surface Brightness Fluctuation (SBF) method. Lauer & Postman (1992) show that the BCG Hubble diagram measured out to 15,000 km s^-1 is highly linear. Calibration of the Hubble diagram zeropoint by SBF will thus yield an accurate far-field measure of H_0 based on the entire volume within 15,000 km s^-1, thus circumventing any strong biases caused by local peculiar velocity fields. This method of reaching the far field is contrasted with those using distance ratios between Virgo and Coma, or any other limited sample of clusters. HST is required as the ground-based SBF method is limited to team developed the SBF method, the first BCG Hubble diagram based on a full-sky, volume-limited BCG sample, played major roles in the calibration of WFPC and WFPC2, and are conducting observations of local galaxies that will validate the SBF zeropoint (through GTO programs). This work uses the SBF method to tie both the Cepheid and Local Group giant-branch distances generated by HST to the large scale Hubble flow, which is most accurately traced by BCGs.

  10. Far-field superresolution by imaging of resonance scattering

    KAUST Repository

    Schuster, Gerard T.; Huang, Y.

    2014-01-01

    We show that superresolution imaging in the far-field region of the sources and receivers is theoretically and practically possible if migration of resonant multiples is employed. A resonant multiple is one that bounces back and forth between two

  11. Far field scattering pattern of differently structured butterfly scales

    NARCIS (Netherlands)

    Giraldo, M. A.; Yoshioka, S.; Stavenga, D. G.

    The angular and spectral reflectance of single scales of five different butterfly species was measured and related to the scale anatomy. The scales of the pierids Pieris rapae and Delias nigrina scatter white light randomly, in close agreement with Lambert's cosine law, which can be well understood

  12. Efficient Compression of Far Field Matrices in Multipole Algorithms based on Spherical Harmonics and Radiating Modes

    Directory of Open Access Journals (Sweden)

    A. Schroeder

    2012-09-01

    Full Text Available This paper proposes a compression of far field matrices in the fast multipole method and its multilevel extension for electromagnetic problems. The compression is based on a spherical harmonic representation of radiation patterns in conjunction with a radiating mode expression of the surface current. The method is applied to study near field effects and the far field of an antenna placed on a ship surface. Furthermore, the electromagnetic scattering of an electrically large plate is investigated. It is demonstrated, that the proposed technique leads to a significant memory saving, making multipole algorithms even more efficient without compromising the accuracy.

  13. Far-field high resolution effects and manipulating of electromagnetic waves based on transformation optics

    Science.gov (United States)

    Ji, XueBin; Zang, XiaoFei; Li, Zhou; Shi, Cheng; Chen, Lin; Cai, Bin; Zhu, YiMing

    2015-05-01

    Based on the transformation optics (TO) and the effective medium theory (EMT), a new illusion media with homogeneous and isotropic materials is proposed to realize the far-field high resolution effects. When two point sources with the separation distance of λ0 / 4 are covered with the illusion media (λ0 is the free-space wavelength), the corresponding far-field pattern is equivalent to the case of two point sources with the separation distance larger than λ0 / 2 in free space, leading to the far-field high resolution effects (in free space, the separation distance of λ0 / 4 is less than half-wavelength, and thus the two point sources cannot be distinguished from each other). Furthermore, such illusion media can be applied to design tunable high-directivity antenna and an angle-dependent floating carpet cloak. Full wave simulations are carried out to verify the performance of our device.

  14. Super-Planckian far-field radiative heat transfer

    Science.gov (United States)

    Fernández-Hurtado, V.; Fernández-Domínguez, A. I.; Feist, J.; García-Vidal, F. J.; Cuevas, J. C.

    2018-01-01

    We present here a theoretical analysis that demonstrates that the far-field radiative heat transfer between objects with dimensions smaller than the thermal wavelength can overcome the Planckian limit by orders of magnitude. To guide the search for super-Planckian far-field radiative heat transfer, we make use of the theory of fluctuational electrodynamics and derive a relation between the far-field radiative heat transfer and the directional absorption efficiency of the objects involved. Guided by this relation, and making use of state-of-the-art numerical simulations, we show that the far-field radiative heat transfer between highly anisotropic objects can largely overcome the black-body limit when some of their dimensions are smaller than the thermal wavelength. In particular, we illustrate this phenomenon in the case of suspended pads made of polar dielectrics like SiN or SiO2. These structures are widely used to measure the thermal transport through nanowires and low-dimensional systems and can be employed to test our predictions. Our work illustrates the dramatic failure of the classical theory to predict the far-field radiative heat transfer between micro- and nanodevices.

  15. Physical optics far field inverse scattering in the time domain

    International Nuclear Information System (INIS)

    Bleistein, N.

    1976-01-01

    The physical optics far field inverse scattering (POFFIS) identity relates the phase and range normalized far field back scattering amplitude to the spatial Fourier transform of the characteristic function of the scattering obstacle. The characteristic function is equal to unity in the region occupied by the obstacle and zero elsewhere. The original identity was derived by Bojarski for impulsive point sources. The result is extended to sources of arbitrary time dependence. One obtains an alternative form of Bojarski's POFFIS identity. One also derives a POFFIS identity in the time domain. Numerically synthesized checks on the method are provided

  16. Couplex1 test case nuclear - Waste disposal far field simulation

    International Nuclear Information System (INIS)

    2001-01-01

    This first COUPLEX test case is to compute a simplified Far Field model used in nuclear waste management simulation. From the mathematical point of view the problem is of convection diffusion type but the parameters are highly varying from one layer to another. Another particularity is the very concentrated nature of the source, both in space and in time. (author)

  17. Far-field potentials in cylindrical and rectangular volume conductors.

    Science.gov (United States)

    Dumitru, D; King, J C; Rogers, W E

    1993-07-01

    The occurrence of a transient dipole is one method of producing a far-field potential. This investigation qualitatively defines the characteristics of the near-field and far-field electrical potentials produced by a transient dipole in both cylindrical and rectangular volume conductors. Most body segments of electrophysiologic interest such as arms, legs, thorax, and neck are roughly cylindrical in shape. A centrally located dipole generator produces a nonzero equipotential region which is found to occur along the cylindrical wall at a distance from the dipole of approximately 1.4 times the cylinder's radius and 1.9 times the cylinder's radius for the center of the cylinder. This distance to the equi-potential zone along the surface wall expands but remains less than 3.0 times the cylindrical radius when the dipole is eccentrically placed. The magnitude of the equipotential region resulting from an asymmetrically placed dipole remains identical to that when the dipole is centrally located. This behavior is found to be very similar in rectangular shallow conducting volumes that model a longitudinal slice of the cylinder, thus allowing a simple experimental model of the cylinder to be utilized. Amplitudes of the equipotential region are inversely proportional to the cylindrical or rectangular volume's cross-sectional area at the location of dipolar imbalance. This study predicts that referential electrode montages, when placed at 3.0 times the radius or greater from a dipolar axially aligned far-field generator in cylindrical homogeneous volume conductors, will record only equipotential far-field effects.

  18. Topological magnetoelectric effects in microwave far-field radiation

    Energy Technology Data Exchange (ETDEWEB)

    Berezin, M.; Kamenetskii, E. O.; Shavit, R. [Microwave Magnetic Laboratory, Department of Electrical and Computer Engineering, Ben Gurion University of the Negev, Beer Sheva (Israel)

    2016-07-21

    Similar to electromagnetism, described by the Maxwell equations, the physics of magnetoelectric (ME) phenomena deals with the fundamental problem of the relationship between electric and magnetic fields. Despite a formal resemblance between the two notions, they concern effects of different natures. In general, ME-coupling effects manifest in numerous macroscopic phenomena in solids with space and time symmetry breakings. Recently, it was shown that the near fields in the proximity of a small ferrite particle with magnetic-dipolar-mode (MDM) oscillations have the space and time symmetry breakings and the topological properties of these fields are different from the topological properties of the free-space electromagnetic fields. Such MDM-originated fields—called magnetoelectric (ME) fields—carry both spin and orbital angular momenta. They are characterized by power-flow vortices and non-zero helicity. In this paper, we report on observation of the topological ME effects in far-field microwave radiation based on a small microwave antenna with a MDM ferrite resonator. We show that the microwave far-field radiation can be manifested with a torsion structure where an angle between the electric and magnetic field vectors varies. We discuss the question on observation of the regions of localized ME energy in far-field microwave radiation.

  19. Far field measurements of phc led prepared by e-beam lithography

    International Nuclear Information System (INIS)

    Hronec, P.; Skriniarova, J.; Kovac, J.; Pudis, D.; Bencurova, A.; Nemec, P.

    2014-01-01

    The paper deals with optical characterization of the Al_0_._2_9_5Ga_0_._7_0_5As/GaAs multi quantum well light emitting diode (LED) structure with patterned photonic crystal (2D PhC). The 2D PhC was patterned on the top of the structure using Electron Beam Direct Write Lithography (EBDWL). The LEDs light-current characteristics were measured by using integrating sphere, where extracted light intensity increase was observed at 10 mA forward current as 24.2 %. Also far field measurements were performed at forward current of 10 mA. Comparison of reference LED and PhC LED far fields shows increase in whole emission area. As a complementary method for extracted light intensity increase evaluation, relative light intensity distributed in the far field was integrated in range of ±60 grad in both θ and φ coordinate of spherical coordinate system. This method shows increase of extracted light intensity as 35.6 %. We suggest this method as more suitable for evaluation of extracted light intensity increase because it omits emission from edges of the LED and thus light is measured only from the area where PhC is patterned. (authors)

  20. A Compact RFID Reader Antenna for UHF Near-Field and Far-Field Operations

    Directory of Open Access Journals (Sweden)

    Lai Xiao zheng

    2013-01-01

    Full Text Available A compact loop antenna is presented for mobile ultrahigh frequency (UHF radio frequency identification (RFID application. This antenna, printed on a 0.8 mm thick FR4 substrate with a small size of 31 mm × 31 mm, achieves good impedance bandwidth from 897 to 928 MHz, which covers USA RFID Band (902–928 MHz. The proposed loop configuration, with a split-ring resonator (SRR coupled inside it, demonstrates strong and uniform magnetic field distribution in the near-field antenna region. Its linearly polarized radiation pattern provides available far-field gain. Finally, the reading capabilities of antenna are up to 56 mm for near-field and 1.05 m for far-field UHF RFID operations, respectively.

  1. Far-field super-resolution imaging of resonant multiples

    KAUST Repository

    Guo, Bowen

    2016-05-20

    We demonstrate for the first time that seismic resonant multiples, usually considered as noise, can be used for super-resolution imaging in the far-field region of sources and receivers. Tests with both synthetic data and field data show that resonant multiples can image reflector boundaries with resolutions more than twice the classical resolution limit. Resolution increases with the order of the resonant multiples. This procedure has important applications in earthquake and exploration seismology, radar, sonar, LIDAR (light detection and ranging), and ultrasound imaging, where the multiples can be used to make high-resolution images.

  2. Far-field superresolution by imaging of resonance scattering

    KAUST Repository

    Schuster, Gerard T.

    2014-10-31

    We show that superresolution imaging in the far-field region of the sources and receivers is theoretically and practically possible if migration of resonant multiples is employed. A resonant multiple is one that bounces back and forth between two scattering points; it can also be the multiple between two smoothly varying interfaces as long as the reflection wave paths partially overlap and reflect from the same Fresnel zone. For a source with frequency f, compared to a one-way trip, N round trips in propagating between two scatterers increase the effective frequency by 2N × f and decrease the effective wavelength by λ/(2N). Thus, multiples can, in principle, be used as high-frequency probes to estimate detailed properties of layers. Tests with both synthetic and field data validate this claim. Improved resolution by multiple imaging is not only feasible for crustal reflections, but might be applicable to mantle and core reverberations recorded by earthquake seismologists.

  3. Field measurement program to determine far field plume dilution parameters

    International Nuclear Information System (INIS)

    Orth, R.C.; Carter, H.H.; Miyasaki, M.T.

    1974-01-01

    A description of the techniques used to obtain measurements of temperature, salinity, tidal velocity and tracer concentration required to determine the far field dilution in a shallow estuary is presented. The study was done to characterize the physical hydrography of the Bush River, a tributary estuary of the Chesapeake Bay, which is a possible recipient of the thermal discharge from a proposed power plant consisting of two 850 MWe nuclear generating units. Measurements of temperature and salinity along the axis of the estuary during periods of high and low fresh water inflow were obtained for use in the development of a one-dimensional-segmented transient state model of the estuary. Computer concentrations from the model compared favorably with measured dye concentrations for the same periods of high and low freshwater inflow

  4. Dynamic characteristics of far-field radiation of current modulated phase-locked diode laser arrays

    Science.gov (United States)

    Elliott, R. A.; Hartnett, K.

    1987-01-01

    A versatile and powerful streak camera/frame grabber system for studying the evolution of the near and far field radiation patterns of diode lasers was assembled and tested. Software needed to analyze and display the data acquired with the steak camera/frame grabber system was written and the total package used to record and perform preliminary analyses on the behavior of two types of laser, a ten emitter gain guided array and a flared waveguide Y-coupled array. Examples of the information which can be gathered with this system are presented.

  5. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Science.gov (United States)

    Hedayati, R.; Mirzaali, M. J.; Vergani, L.; Zadpoor, A. A.

    2018-03-01

    Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of "action-at-a-distance" metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular) materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson's ratios as a way of making "action-at-a-distance" metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable) robotics and exosuits.

  6. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Directory of Open Access Journals (Sweden)

    R. Hedayati

    2018-03-01

    Full Text Available Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of “action-at-a-distance” metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson’s ratios as a way of making “action-at-a-distance” metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable robotics and exosuits.

  7. Report of the Working Group on Far Field Accelerators

    International Nuclear Information System (INIS)

    Cha-Mei Tang

    1992-01-01

    This report describes the accomplishments of the Working Group on Far Field Accelerators. In addition to hearing presentations of current research, the group produced designs for ''100 MeV'' demonstration accelerators, ''1 GeV'' conceptual accelerators and a small electron beam source. Two of the ''100 MeV'' designs, an Inverse Free Electron Laser (IFEL) and an Inverse Cerenkov Accelerator (ICA), use the CO 2 laser and the 50 MeV linac at the Advanced Test Facility (ATF) at Brookhaven National Laboratory (BNL), requiring only modest changes in the current experimental setups. By upgrading the laser, an ICA design demonstrated 1 GeV acceleration in a gas cell about 50 cm in length. For high average power accelerators, examples based on the IFEL concept were also produced utilizing accelerators driven by high average power FELs. The Working Group also designed a small electron beam source based on the inverse electron cyclotron resonance concept. Accelerators based on the IFEL and ICA may be the first to achieve ''100 MeV'' and ''1 GeV'' energy gain demonstration with high accelerating gradients

  8. Modern design of far-field target motion simulators

    Science.gov (United States)

    Hauser, Robin; Swamp, Michael; Havlicsek, Howard

    2006-05-01

    Target Motion Simulators (TMS) are often used in conjunction with Flight Motion Simulators (FMS) to provide a realistic simulation of tracking and target engagement. For near-field applications, the TMS has typically been implemented with two additional gimbals around the FMS. For far-field applications, such as a radar, the TMS has traditionally been implemented with curvilinear X-Y Frames. A curvilinear frame placed at the proper distance from the FMS has the benefit of always pointing the Target back to the FMS intersection of axes. In most cases the curvilinear TMS provides good results. However, the curvilinear TMS lacks the possibility to change the distance between Target and Seeker, which is needed for operation with different radar wavelengths. Acutronic has developed a new approach using a flat frame (X-Y) TMS coupled with a gimballed payload mount that has the possibility of being used at various distances without losing the functionality of continuous pointing back to the seeker. This paper describes the electro-mechanical design and gives an overview of the Computer and Controllers used. It further addresses the problem of coordination transformation that is needed to obtain the correct pointing.

  9. Topological sensitivity based far-field detection of elastic inclusions

    Directory of Open Access Journals (Sweden)

    Tasawar Abbas

    2018-03-01

    Full Text Available The aim of this article is to present and rigorously analyze topological sensitivity based algorithms for detection of diametrically small inclusions in an isotropic homogeneous elastic formation using single and multiple measurements of the far-field scattering amplitudes. A L2-cost functional is considered and a location indicator is constructed from its topological derivative. The performance of the indicator is analyzed in terms of the topological sensitivity for location detection and stability with respect to measurement and medium noises. It is established that the location indicator does not guarantee inclusion detection and achieves only a low resolution when there is mode-conversion in an elastic formation. Accordingly, a weighted location indicator is designed to tackle the mode-conversion phenomenon. It is substantiated that the weighted function renders the location of an inclusion stably with resolution as per Rayleigh criterion. 2000 MSC: 35R30, 35L05, 74B05, 47A52, 65J20, Keywords: Inverse elastic scattering, Elasticity imaging, Topological derivative, Resolution analysis, Stability analysis

  10. A thermomechanical far-field model of Yucca Mountain

    International Nuclear Information System (INIS)

    Brandshaug, T.

    1991-04-01

    Thermal and mechanical finite element far-field models have been constructed for a potential repository site in the Topopah Spring Thermal/mechanical Unit at Yucca Mountain on the Nevada Test Site. The models reflect site-specific information that was available at the time of the study on the material properties and structural character of Yucca Mountain. The thermal model simulates transient heat transfer resulting from the emplacement of heat-generating nuclear waste in the repository. Simulation of boiling of the pore water is included in the model. The mechanical model simulates the tuff at Yucca Mountain as being an elastic/plastic, isotropic, heterogeneous continuum with one ubiquitous vertical joint set. The initial conditions of the mechanical model are based on a gravitational stress field. The model uses the temperatures predicted by the thermal finite element model as input to predict thermal stresses and displacements induced by the presence of the repository. Plasticity is incorporated in shear (fracture slip) and tension (fracture opening) by using a Mohr-Coulomb failure criterion. 6 refs., 15 figs., 2 tabs

  11. Far-Field and Middle-Field Vertical Velocities Associated with Megathrust Earthquakes

    Science.gov (United States)

    Fleitout, L.; Trubienko, O.; Klein, E.; Vigny, C.; Garaud, J.; Shestakov, N.; Satirapod, C.; Simons, W. J.

    2013-12-01

    The recent megathrust earthquakes (Sumatra, Chili and Japan) have induced far-field postseismic subsidence with velocities from a few mm/yr to more than 1cm/yr at distances from 500 to 1500km from the earthquake epicentre, for several years following the earthquake. This subsidence is observed in Argentina, China, Korea, far-East Russia and in Malaysia and Thailand as reported by Satirapod et al. ( ASR, 2013). In the middle-field a very pronounced uplift is localized on the flank of the volcanic arc facing the trench. This is observed both over Honshu, in Chile and on the South-West coast of Sumatra. In Japan, the deformations prior to Tohoku earthquake are well measured by the GSI GPS network: While the East coast was slightly subsiding, the West coast was raising. A 3D finite element code (Zebulon-Zset) is used to understand the deformations through the seismic cycle in the areas surrounding the last three large subduction earthquakes. The meshes designed for each region feature a broad spherical shell portion with a viscoelastic asthenosphere. They are refined close to the subduction zones. Using these finite element models, we find that the pattern of the predicted far-field vertical postseismic displacements depends upon the thicknesses of the elastic plate and of the low viscosity asthenosphere. A low viscosity asthenosphere at shallow depth, just below the lithosphere is required to explain the subsidence at distances from 500 to 1500km. A thick (for example 600km) asthenosphere with a uniform viscosity predicts subsidence too far away from the trench. Slip on the subduction interface is unable tot induce the observed far-field subsidence. However, a combination of relaxation in a low viscosity wedge and slip or relaxation on the bottom part of the subduction interface is necessary to explain the observed postseismic uplift in the middle-field (volcanic arc area). The creep laws of the various zones used to explain the postseismic data can be injected in

  12. Babinet’s principle for scalar complex objects in the far field

    Science.gov (United States)

    Rodriguez-Zurita, G.; Rickenstorff, C.; Pastrana-Sánchez, R.; Vázquez-Castillo, J. F.; Robledo-Sanchez, C.; Meneses-Fabian, C.; Toto-Arellano, N. I.

    2014-10-01

    Babinet’s principle is briefly reviewed, especially regarding the zeroth diffraction order of the far field diffraction pattern associated with a given aperture. The pattern is basically described by the squared modulus of the Fourier transform of its amplitude distribution (scalar case). In this paper, complementary objects are defined with respect to complex values and not only with respect to unity in order to include phase objects and phase modulation. It is shown that the difference in complementary patterns can be sometimes a bright spot at the zero order location as is widely known, but also, it can be a gray spot or even a dark one. Conditions of occurrence for each case are given as well as some numerical and experimental examples.

  13. Babinet’s principle for scalar complex objects in the far field

    International Nuclear Information System (INIS)

    Rodriguez-Zurita, G; Rickenstorff, C; Pastrana-Sánchez, R; Vázquez-Castillo, J F; Robledo-Sanchez, C; Meneses-Fabian, C; Toto-Arellano, N I

    2014-01-01

    Babinet’s principle is briefly reviewed, especially regarding the zeroth diffraction order of the far field diffraction pattern associated with a given aperture. The pattern is basically described by the squared modulus of the Fourier transform of its amplitude distribution (scalar case). In this paper, complementary objects are defined with respect to complex values and not only with respect to unity in order to include phase objects and phase modulation. It is shown that the difference in complementary patterns can be sometimes a bright spot at the zero order location as is widely known, but also, it can be a gray spot or even a dark one. Conditions of occurrence for each case are given as well as some numerical and experimental examples. (paper)

  14. Fourier-transform ghost imaging with pure far-field correlated thermal light

    International Nuclear Information System (INIS)

    Liu Honglin; Shen Xia; Han Shensheng; Zhu Daming

    2007-01-01

    Pure far-field correlated thermal light beams are created with phase grating, and Fourier-transform ghost imaging depending only on the far-field correlation is demonstrated experimentally. Theoretical analysis and the results of experimental investigation of this pure far-field correlated thermal light are presented. Applications which may be exploited with this imaging scheme are discussed

  15. Plasmonic Devices for Near and Far-Field Applications

    KAUST Repository

    Alrasheed, Salma

    2017-11-30

    Plasmonics is an important branch of nanophotonics and is the study of the interaction of electromagnetic fields with the free electrons in a metal at metallic/dielectric interfaces or in small metallic nanostructures. The electric component of an exciting electromagnetic field can induce collective electron oscillations known as surface plasmons. Such oscillations lead to the localization of the fields that can be at sub-wavelength scale and to its significant enhancement relative to the excitation fields. These two characteristics of localization and enhancement are the main components that allow for the guiding and manipulation of light beyond the diffraction limit. This thesis focuses on developing plasmonic devices for near and far-field applications. In the first part of the thesis, we demonstrate the detection of single point mutation in peptides from multicomponent mixtures for early breast cancer detection using selfsimilar chain (SCC) plasmonic devices that show high field enhancement and localization. In the second part of this work, we investigate the anomalous reflection of light for TM polarization for normal and oblique incidence in the visible regime. We propose gradient phase gap surface plasmon (GSP) metasurfaces that exhibit high conversion efficiency (up to ∼97% of total reflected light) to the anomalous reflection angle for blue, green and red wavelengths at normal and oblique incidence. In the third part of the thesis, we present a theoretical approach to narrow the plasmon linewidth and enhance the near-field intensity at a plasmonic dimer gap (hot spot) through coupling the electric localized surface plasmon (LSP) resonance of a silver hemispherical dimer with the resonant modes of a Fabry-Perot (FP) cavity. In the fourth part of this work, we demonstrate numerically bright color pixels that are highly polarized and broadly tuned using periodic arrays of metal nanosphere dimers on a glass substrate. In the fifth and final part of the

  16. Polarization-Dependent Quasi-Far-Field Superfocusing Strategy of Nanoring-Based Plasmonic Lenses.

    Science.gov (United States)

    Sun, Hao; Zhu, Yechuan; Gao, Bo; Wang, Ping; Yu, Yiting

    2017-12-01

    The two-dimensional superfocusing of nanoring-based plasmonic lenses (NRPLs) beyond the diffraction limit in the far-field region remains a great challenge at optical wavelengths. In this paper, in addition to the modulation of structural parameters, we investigated the polarization-dependent focusing performance of a NRPL employing the finite-difference time-domain (FDTD) method. By utilizing the state of polarization (SOP) of incident light, we successfully realize the elliptical-, donut-, and circular-shape foci. The minimum full widths at half maximum (FWHMs) of these foci are ~0.32, ~0.34, and ~0.42 λ 0 in the total electric field, respectively, and the depth of focus (DOF) lies in 1.41~1.77 λ 0 . These sub-diffraction-limit foci are well controlled in the quasi-far-field region. The underlying physical mechanism on the focal shift and an effective way to control the focusing position are proposed. Furthermore, in the case of a high numerical aperture, the longitudinal component, which occupies over 80% of the electric-field energy, decides the focusing patterns of the foci. The achieved sub-diffraction-limit focusing can be widely used for many engineering applications, including the super-resolution imaging, particle acceleration, quantum optical information processing, and optical data storage.

  17. Recovering an elastic obstacle containing embedded objects by the acoustic far-field measurements

    Science.gov (United States)

    Qu, Fenglong; Yang, Jiaqing; Zhang, Bo

    2018-01-01

    Consider the inverse scattering problem of time-harmonic acoustic waves by a 3D bounded elastic obstacle which may contain embedded impenetrable obstacles inside. We propose a novel and simple technique to show that the elastic obstacle can be uniquely recovered by the acoustic far-field pattern at a fixed frequency, disregarding its contents. Our method is based on constructing a well-posed modified interior transmission problem on a small domain and makes use of an a priori estimate for both the acoustic and elastic wave fields in the usual H 1-norm. In the case when there is no obstacle embedded inside the elastic body, our method gives a much simpler proof for the uniqueness result obtained previously in the literature (Natroshvili et al 2000 Rend. Mat. Serie VII 20 57-92 Monk and Selgas 2009 Inverse Problems Imaging 3 173-98).

  18. Calculation of far-field scattering from nonspherical particles using a geometrical optics approach

    Science.gov (United States)

    Hovenac, Edward A.

    1991-01-01

    A numerical method was developed using geometrical optics to predict far-field optical scattering from particles that are symmetric about the optic axis. The diffractive component of scattering is calculated and combined with the reflective and refractive components to give the total scattering pattern. The phase terms of the scattered light are calculated as well. Verification of the method was achieved by assuming a spherical particle and comparing the results to Mie scattering theory. Agreement with the Mie theory was excellent in the forward-scattering direction. However, small-amplitude oscillations near the rainbow regions were not observed using the numerical method. Numerical data from spheroidal particles and hemispherical particles are also presented. The use of hemispherical particles as a calibration standard for intensity-type optical particle-sizing instruments is discussed.

  19. Numerical Computation of the Nonlinear Far Field of Ultrasonic Waves Scattered by Closed Cracks of Various Orientations

    OpenAIRE

    Blanloeuil , Philippe; Meziane , Anissa; Norris , Andrew N.; Renier , Mathieu; Veidt , Martin

    2014-01-01

    International audience; The directivity patterns of the higher harmonics generated by the interaction between a bulk wave and a closed crack are obtained in the far field. A Finite Element (FE) model gives the near field solution which is then analytically propagated with expressions based on Hankel functions. The crack is modeled by an interface of unilateral contact with CoulombÕs friction which takes into account a compression pre-stress s0 that closes the crack. The mode conversion occurr...

  20. Emergence of spatiotemporal chaos arising from far-field breakup of spiral waves in the plankton ecological systems

    International Nuclear Information System (INIS)

    Quan-Xing, Liu; Gui-Quan, Sun; Zhen, Jin; Bai-Lian, Li

    2009-01-01

    It has been reported that the minimal spatially extended phytoplankton–zooplankton system exhibits both temporal regular/chaotic behaviour, and spatiotemporal chaos in a patchy environment. As a further investigation by means of computer simulations and theoretical analysis, in this paper we observe that the spiral waves may exist and the spatiotemporal chaos emerge when the parameters are within the mixed Turing–Hopf bifurcation region, which arises from the far-field breakup of the spiral waves over a large range of diffusion coefficients of phytoplankton and zooplankton. Moreover, the spatiotemporal chaos arising from the far-field breakup of spiral waves does not gradually invade the whole space of that region. Our results are confirmed by nonlinear bifurcation of wave trains. We also discuss ecological implications of these spatially structured patterns. (general)

  1. Far-field and Fresnel Liquid Crystal Geometric Phase Holograms via Direct-Write Photo-Alignment

    Directory of Open Access Journals (Sweden)

    Xiao Xiang

    2017-12-01

    Full Text Available We study computer-generated geometric-phase holograms (GPHs realized by photo-aligned liquid crystals, in both simulation and experiment. We demonstrate both far-field and Fresnel holograms capable of producing far-field and near-field images with preserved fidelity for all wavelengths. The GPHs are fabricated by patterning a photo-alignment layer (PAL using a direct-write laser scanner and coating the surface with a polymerizable liquid crystal (i.e., a reactive mesogen. We study various recording pixel sizes, down to 3 μm, that are easily recorded in the PAL. We characterize the fabricated elements and find good agreement with theory and numerical simulation. Because of the wavelength independent geometric phase, the (phase fidelity of the replay images is preserved for all wavelengths, unlike conventional dynamic phase holograms. However, governed by the diffraction equation, the size and location of a reconstructed image depends on the replay wavelength for far-field and near-field GPHs, respectively. These offer interesting opportunities for white-light holography.

  2. Metal/Polymer Based Stretchable Antenna for Constant Frequency Far-Field Communication in Wearable Electronics

    KAUST Repository

    Hussain, Aftab M.; Ghaffar, Farhan A.; Park, Sung I.; Rogers, John A.; Shamim, Atif; Hussain, Muhammad Mustafa

    2015-01-01

    electronics which can physically stretch to absorb the strain associated with body movements. While research in stretchable electronics has started to gain momentum, a stretchable antenna which can perform far-field communications and can operate at constant

  3. Some far-field acoustics characteristics of the XV-15 tilt-rotor aircraft

    Science.gov (United States)

    Golub, Robert A.; Conner, David A.; Becker, Lawrence E.; Rutledge, C. Kendall; Smith, Rita A.

    1990-01-01

    Far-field acoustics tests have been conducted on an instrumented XV-15 tilt-rotor aircraft. The purpose of these acoustic measurements was to create an encompassing, high confidence (90 percent), and accurate (-1.4/ +1/8 dB theoretical confidence interval) far-field acoustics data base to validate ROTONET and other current rotorcraft noise prediction computer codes. This paper describes the flight techniques used, with emphasis on the care taken to obtain high-quality far-field acoustic data. The quality and extensiveness of the data base collected are shown by presentation of ground acoustic contours for level flyovers for the airplane flight mode and for several forward velocities and nacelle tilts for the transition mode and helicopter flight mode. Acoustic pressure time-histories and fully analyzed ensemble averaged far-field data results (spectra) are shown for each of the ground contour cases.

  4. Reciprocity Method for Obtaining the Far Fields Generated by a Source Inside or Near a Microparticle

    National Research Council Canada - National Science Library

    Hill, Steven

    1997-01-01

    We show that the far fields generated by a source inside or near a microparticle can be obtained readily by using the reciprocity theorem along with the internal or near fields generated by plane wave illumination...

  5. Near-Field to Far-Field Transformation Techniques with Spiral Scannings: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Renato Cicchetti

    2014-01-01

    Full Text Available An overview of the near-field-far-field (NF-FF transformation techniques with innovative spiral scannings, useful to derive the radiation patterns of the antennas commonly employed in the modern wireless communication systems, is provided in this paper. The theoretical background and the development of a unified theory of the spiral scannings for quasi-spherical and nonspherical antennas are described, and an optimal sampling interpolation expansion to evaluate the probe response on a quite arbitrary rotational surface from a nonredundant number of its samples, collected along a proper spiral wrapping it, is presented. This unified theory can be applied to spirals wrapping the conventional scanning surfaces and makes it possible to accurately reconstruct the NF data required by the NF-FF transformation employing the corresponding classical scanning. A remarkable reduction of the measurement time is so achieved, due to the use of continuous and synchronized movements of the positioning systems and to the reduced number of needed NF measurements. Some numerical and experimental results relevant to the spherical spiral scanning case when dealing with quasi-planar and electrically long antennas are shown.

  6. Benchmark Modeling of the Near-Field and Far-Field Wave Effects of Wave Energy Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Rhinefrank, Kenneth E; Haller, Merrick C; Ozkan-Haller, H Tuba

    2013-01-26

    This project is an industry-led partnership between Columbia Power Technologies and Oregon State University that will perform benchmark laboratory experiments and numerical modeling of the near-field and far-field impacts of wave scattering from an array of wave energy devices. These benchmark experimental observations will help to fill a gaping hole in our present knowledge of the near-field effects of multiple, floating wave energy converters and are a critical requirement for estimating the potential far-field environmental effects of wave energy arrays. The experiments will be performed at the Hinsdale Wave Research Laboratory (Oregon State University) and will utilize an array of newly developed Buoys' that are realistic, lab-scale floating power converters. The array of Buoys will be subjected to realistic, directional wave forcing (1:33 scale) that will approximate the expected conditions (waves and water depths) to be found off the Central Oregon Coast. Experimental observations will include comprehensive in-situ wave and current measurements as well as a suite of novel optical measurements. These new optical capabilities will include imaging of the 3D wave scattering using a binocular stereo camera system, as well as 3D device motion tracking using a newly acquired LED system. These observing systems will capture the 3D motion history of individual Buoys as well as resolve the 3D scattered wave field; thus resolving the constructive and destructive wave interference patterns produced by the array at high resolution. These data combined with the device motion tracking will provide necessary information for array design in order to balance array performance with the mitigation of far-field impacts. As a benchmark data set, these data will be an important resource for testing of models for wave/buoy interactions, buoy performance, and far-field effects on wave and current patterns due to the presence of arrays. Under the proposed project we will initiate

  7. Random source generating far field with elliptical flat-topped beam profile

    International Nuclear Information System (INIS)

    Zhang, Yongtao; Cai, Yangjian

    2014-01-01

    Circular and rectangular multi-Gaussian Schell-model (MGSM) sources which generate far fields with circular and rectangular flat-topped beam profiles were introduced just recently (Sahin and Korotkova 2012 Opt. Lett. 37 2970; Korotkova 2014 Opt. Lett. 39 64). In this paper, a random source named an elliptical MGSM source is introduced. An analytical expression for the propagation factor of an elliptical MGSM beam is derived. Furthermore, an analytical propagation formula for an elliptical MGSM beam passing through a stigmatic ABCD optical system is derived, and its propagation properties in free space are studied. It is interesting to find that an elliptical MGSM source generates a far field with an elliptical flat-topped beam profile, being qualitatively different from that of circular and rectangular MGSM sources. The ellipticity and the flatness of the elliptical flat-topped beam profile in the far field are determined by the initial coherence widths and the beam index, respectively. (paper)

  8. Analysis and suppression of reflections in far-field antenna measurement ranges

    OpenAIRE

    Sierra Castañer, Manuel; Cano Facila, Francisco Jose; Foged, Lars Jacob; Saccardi, Francesco; Nader Kawassaki, Guilherme; Raimundi, Lucas dos Reis; Vilela Rezende, Stefano Albino

    2013-01-01

    This paper presents the analysis of the reflections in two kind of spherical far field ranges: one if the classical acquisition where the AUT is rotated and the second one corresponds to the systems where the AUT is fixed and the antenna probe is rotated. In large far field systems this is not possible, but this can be used to the measurement of small antennas, for instance, with the SATIMO StarGate system. In both cases, it is assumed that only one frequency is acquired and the results shoul...

  9. Analysis of ventilation systems subjected to explosive transients: far-field analysis

    International Nuclear Information System (INIS)

    Tang, P.K.; Andrae, R.W.; Bolstad, J.W.; Duerre, K.H.; Gregory, W.S.

    1981-11-01

    Progress in developing a far-field explosion simulation computer code is outlined. The term far-field implies that this computer code is suitable for modeling explosive transients in ventilation systems that are far removed from the explosive event and are rather insensitive to the particular characteristics of the explosive event. This type of analysis is useful when little detailed information is available and the explosive event is described parametrically. The code retains all the features of the TVENT code and allows completely compressible flow with inertia and choking effects. Problems that illustrate the capabilities and limitations of the code are described

  10. Modelling of Far-Field Mixing of Industrial Effluent Plume in Ambient ...

    African Journals Online (AJOL)

    This study sought to describe the dynamics of advective and dispersive transport of the effluent plume in the river and also ascertain the extent of its effect from discharge location to downstream far-field region. A homogenous differential equation was used as analytics to describe the physical process that describes the ...

  11. Quantitative and Isolated Measurement of Far-Field Light Scattering by a Single Nanostructure

    Science.gov (United States)

    Kim, Donghyeong; Jeong, Kwang-Yong; Kim, Jinhyung; Ee, Ho-Seok; Kang, Ju-Hyung; Park, Hong-Gyu; Seo, Min-Kyo

    2017-11-01

    Light scattering by nanostructures has facilitated research on various optical phenomena and applications by interfacing the near fields and free-propagating radiation. However, direct quantitative measurement of far-field scattering by a single nanostructure on the wavelength scale or less is highly challenging. Conventional back-focal-plane imaging covers only a limited solid angle determined by the numerical aperture of the objectives and suffers from optical aberration and distortion. Here, we present a quantitative measurement of the differential far-field scattering cross section of a single nanostructure over the full hemisphere. In goniometer-based far-field scanning with a high signal-to-noise ratio of approximately 27.4 dB, weak scattering signals are efficiently isolated and detected under total-internal-reflection illumination. Systematic measurements reveal that the total and differential scattering cross sections of a Au nanorod are determined by the plasmonic Fabry-Perot resonances and the phase-matching conditions to the free-propagating radiation, respectively. We believe that our angle-resolved far-field measurement scheme provides a way to investigate and evaluate the physical properties and performance of nano-optical materials and phenomena.

  12. Prediction of transport phenomena in near and far field: interaction solid phase/fluid phase

    International Nuclear Information System (INIS)

    Mingarro, E.

    1995-01-01

    The prediction of transport phenomena in near and far field is presented in the present report. The study begins with the analysis of solid phases stability: solubility of storage waste: UO 2 and solubility of radionuclides the redox and sorption-desorption conditions are the last aspects studied to predict the transport phenomena

  13. Ground plane detection for autonomous robots in complex environments inclined with flexed far-field terrains

    CSIR Research Space (South Africa)

    Osunmakind, IO

    2009-11-01

    Full Text Available In this paper, collective intelligence of the Emergent Situation Awareness (ESA) technology is proposed as a supportive strategy for autonomous robotic navigation. The ability to reveal uncertainties over time on flexed far-field is a ground plane...

  14. Near-to far-field transformation in the aperiodic Fourier modal method

    NARCIS (Netherlands)

    Rook, R.; Pisarenco, M.; Setija, I.D.

    2013-01-01

    This paper addresses the task of obtaining the far-field spectrum for a finite structure given the near-field calculated by the aperiodic Fourier modal method in contrast-field formulation (AFMM-CFF). The AFMM-CFF efficiently calculates the solution to Maxwell's equations for a finite structure by

  15. Far-field self-focusing and -defocusing radiation behaviors of the electroluminescent light sources due to negative refraction.

    Science.gov (United States)

    Yin, Yu-Feng; Lin, Yen-Chen; Tsai, Tsung-Han; Shen, Yi-Chun; Huang, Jianjang

    2013-01-15

    In recent years, researchers have demonstrated negative refraction theoretically and experimentally by pumping optical power into photonic crystal (PhC) or waveguide structures. The concept of negative refraction can be used to create a perfect lens that focuses an object smaller than the wavelength. By inserting two-dimensional PhCs into the peripheral of a semiconductor light emitting structure, this study presents an electroluminescent device with negative refraction in the visible wavelength range. This approach produces polarization dependent collimation behavior in far-field radiation patterns. The modal dispersion of negative refraction results in strong group velocity modulation, and self-focusing and -defocusing behaviors are apparent from light extraction. This study further verifies experimental results by using theoretic calculations based on equifrequency contours.

  16. A far-field-viewing sensor for making analytical measurements in remote locations.

    Science.gov (United States)

    Michael, K L; Taylor, L C; Walt, D R

    1999-07-15

    We demonstrate a far-field-viewing GRINscope sensor for making analytical measurements in remote locations. The GRINscope was fabricated by permanently affixing a micro-Gradient index (GRIN) lens on the distal face of a 350-micron-diameter optical imaging fiber. The GRINscope can obtain both chemical and visual information. In one application, a thin, pH-sensitive polymer layer was immobilized on the distal end of the GRINscope. The ability of the GRINscope to visually image its far-field surroundings and concurrently detect pH changes in a flowing stream was demonstrated. In a different application, the GRINscope was used to image pH- and O2-sensitive particles on a remote substrate and simultaneously measure their fluorescence intensity in response to pH or pO2 changes.

  17. Far-Field Power Transmissions in Orthotropic Plates: A New Approach

    Directory of Open Access Journals (Sweden)

    Nirmal K. Mandal

    2008-01-01

    Full Text Available The structural intensity (SI technique is an essential tool for locating and ranking vibration sources and sinks on structures. It can quantify vibration fields by plotting a vector map of energy transmission on the structures. In this paper, a different strategy, changing coordinate systems of plate equations, is used to develop an intensity equation from shear force components in both x and y directions. The formulation is carried out in the frequency domain considering flexural waves. Orthotropic plate theory, far-field conditions, Fourier transform, and finite difference approximation are considered. The same intensity definition is obtained using this different strategy. A dual-channel FFT analyser is essential for data acquisition to get an intensity vector in a particular direction for far-field conditions.

  18. Review of speciation and solubility of radionuclides in the near and far field. Pt. 2

    International Nuclear Information System (INIS)

    Smith-Briggs, J.L.

    1992-01-01

    This report represents Part 2 in a series of three reports which review the speciation and solubility of radionuclides in the near and far field. Part 2 is a general bibliography from 1978 to 1991. This report contains the bibliography for the review of speciation and solubility radionuclides in the near and far field from 1978 to 1991. The importance of the solubility and speciation of radionuclides in relation to the safety assessment of the repository is discussed. Solubility is defined, both theoretically and pragmatically, and the factors which influence solubility and speciation are discussed. The literature search was performed using the INIS database. The UKAEA RECAP database, the NIREX report bibliography and a list of DOE reports provided by the DOE were also used. The bibliography is divided into five sections, solubility and speciation experimental data, basic thermodynamic data, solubility limiting solid phases, experimental design and review and overview articles. Some references appear in more than one section. (Author)

  19. Review of speciation and solubility of radionuclides in the near and far field. Pt. 1

    International Nuclear Information System (INIS)

    Smith-Briggs, J.L.

    1992-01-01

    This report represents Part 1 in a series of three reports which review the speciation and solubility of radionuclides in the near and far field. Part 1 reviews the research funded by UK Nirex Ltd (NIREX) and the Department of the Environment into the solubility and speciation of radionuclides in the near and far fields of a radioactive waste repository. The review is focused on the particular situation prevailing in the UK. UK Nirex Limited are currently planning the development of a deep geological repository for low and intermediate level wastes. In the basic design it is envisaged that the waste material would be immobilised and packed into steel or concrete containers. These containers would be placed in vaults and then backfilled with a cemetitious grout. (Author)

  20. Restoration of diffracted far field at the output of circular diffraction waveplate

    International Nuclear Information System (INIS)

    Hovhannisyan, D; Margaryan, H; Abrahamyan, V; Hakobyan, N; Tabiryan, N

    2014-01-01

    The light propagation in an anisotropic periodic media, such us circular diffraction waveplate (CDW) by a finite-difference time-domain (FDTD) technique is studied. The FDTD numerical simulation and the subsequent Fourier transform of the diffracted electric near field was been used for study of ability of CDW to diffract a laser beam and simultaneously convert polarization state. The FDTD simulation results used to restore the diffracted electric far field at the CDW output. an abstract

  1. Insights on proximity effect and multiphoton induced luminescence from gold nanospheres in far field optical microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Borglin, Johan [Biomedical Photonics Group, Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 412 96 Gothenburg (Sweden); Department of Physics, University of Gothenburg, Kemivägen 10, 412 96 Gothenburg (Sweden); Guldbrand, Stina [Department of Physics, University of Gothenburg, Kemivägen 10, 412 96 Gothenburg (Sweden); Evenbratt, Hanne [Pharmaceutical Technology, Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemigården 4, 412 96 Gothenburg (Sweden); Kirejev, Vladimir; Ericson, Marica B., E-mail: marica.ericson@chem.gu.se [Biomedical Photonics Group, Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 412 96 Gothenburg (Sweden); Grönbeck, Henrik [Department of Applied Physics, Chalmers University of Technology, Kemivägen 9, 412 96 Gothenburg (Sweden)

    2015-12-07

    Gold nanoparticles can be visualized in far-field multiphoton laser-scanning microscopy (MPM) based on the phenomena of multiphoton induced luminescence (MIL). This is of interest for biomedical applications, e.g., for cancer diagnostics, as MPM allows for working in the near-infrared (NIR) optical window of tissue. It is well known that the aggregation of particles causes a redshift of the plasmon resonance, but its implications for MIL applying far-field MPM should be further exploited. Here, we explore MIL from 10 nm gold nanospheres that are chemically deposited on glass substrates in controlled coverage gradients using MPM operating in NIR range. The substrates enable studies of MIL as a function of inter-particle distance and clustering. It was shown that MIL was only detected from areas on the substrates where the particle spacing was less than one particle diameter, or where the particles have aggregated. The results are interpreted in the context that the underlying physical phenomenon of MIL is a sequential two-photon absorption process, where the first event is driven by the plasmon resonance. It is evident that gold nanospheres in this size range have to be closely spaced or clustered to exhibit detectable MIL using far-field MPM operating in the NIR region.

  2. Far-Field Focus and Dispersionless Anticrossing Bands in Two-Dimensional Photonic Crystals

    Directory of Open Access Journals (Sweden)

    Xiaoshuang Chen

    2007-01-01

    Full Text Available We review the simulation work for the far-field focus and dispersionless anticrossing bands in two-dimensional (2D photonic crystals. In a two-dimensional photonic-crystal-based concave lens, the far-field focus of a plane wave is given by the distance between the focusing point and the lens. Strong and good-quality far-field focusing of a transmitted wave, explicitly following the well-known wave-beam negative refraction law, can be achieved. The spatial frequency information of the Bloch mode in multiple Brillouin zones (BZs is investigated in order to indicate the wave propagation in two different regions. When considering the photonic transmission in a 2D photonic crystal composed of a negative phase-velocity medium (NPVM, it is shown that the dispersionless anticrossing bands are generated by the couplings among the localized surface polaritons of the NPVM rods. The photonic band structures of the NPVM photonic crystals are characterized by a topographical continuous dispersion relationship accompanied by many anticrossing bands.

  3. Insights on proximity effect and multiphoton induced luminescence from gold nanospheres in far field optical microscopy

    International Nuclear Information System (INIS)

    Borglin, Johan; Guldbrand, Stina; Evenbratt, Hanne; Kirejev, Vladimir; Ericson, Marica B.; Grönbeck, Henrik

    2015-01-01

    Gold nanoparticles can be visualized in far-field multiphoton laser-scanning microscopy (MPM) based on the phenomena of multiphoton induced luminescence (MIL). This is of interest for biomedical applications, e.g., for cancer diagnostics, as MPM allows for working in the near-infrared (NIR) optical window of tissue. It is well known that the aggregation of particles causes a redshift of the plasmon resonance, but its implications for MIL applying far-field MPM should be further exploited. Here, we explore MIL from 10 nm gold nanospheres that are chemically deposited on glass substrates in controlled coverage gradients using MPM operating in NIR range. The substrates enable studies of MIL as a function of inter-particle distance and clustering. It was shown that MIL was only detected from areas on the substrates where the particle spacing was less than one particle diameter, or where the particles have aggregated. The results are interpreted in the context that the underlying physical phenomenon of MIL is a sequential two-photon absorption process, where the first event is driven by the plasmon resonance. It is evident that gold nanospheres in this size range have to be closely spaced or clustered to exhibit detectable MIL using far-field MPM operating in the NIR region

  4. Far-field tsunami magnitude determined from ocean-bottom pressure gauge data around Japan

    Science.gov (United States)

    Baba, T.; Hirata, K.; Kaneda, Y.

    2003-12-01

    \\hspace*{3mm}Tsunami magnitude is the most fundamental parameter to scale tsunamigenic earthquakes. According to Abe (1979), the tsunami magnitude, Mt, is empirically related to the crest to trough amplitude, H, of the far-field tsunami wave in meters (Mt = logH + 9.1). Here we investigate the far-field tsunami magnitude using ocean-bottom pressure gauge data. The recent ocean-bottom pressure measurements provide more precise tsunami data with a high signal-to-noise ratio. \\hspace*{3mm}Japan Marine Science and Technology Center is monitoring ocean bottom pressure fluctuations using two submarine cables of depths of 1500 - 2400 m. These geophysical observatory systems are located off Cape Muroto, Southwest Japan, and off Hokkaido, Northern Japan. The ocean-bottom pressure data recorded with the Muroto and Hokkaido systems have been collected continuously since March, 1997 and October, 1999, respectively. \\hspace*{3mm}Over the period from March 1997 to June 2003, we have observed four far-field tsunami signals, generated by earthquakes, on ocean-bottom pressure records. These far-field tsunamis were generated by the 1998 Papua New Guinea eq. (Mw 7.0), 1999 Vanuatu eq. (Mw 7.2), 2001 Peru eq. (Mw 8.4) and 2002 Papua New Guinea eq. (Mw 7.6). Maximum amplitude of about 30 mm was recorded by the tsunami from the 2001 Peru earthquake. \\hspace*{3mm}Direct application of the Abe's empirical relation to ocean-bottom pressure gauge data underestimates tsunami magnitudes by about an order of magnitude. This is because the Abe's empirical relation was derived only from tsunami amplitudes with coastal tide gauges where tsunami is amplified by the shoaling of topography and the reflection at the coastline. However, these effects do not work for offshore tsunami in deep oceans. In general, amplification due to shoaling near the coastline is governed by the Green's Law, in which the tsunami amplitude is proportional to h-1/4, where h is the water depth. Wave amplitude also is

  5. Comparison of predicted far-field temperatures for discrete and smeared heat sources

    International Nuclear Information System (INIS)

    Ryder, E.E.

    1992-01-01

    A fundamental concern in the design of the potential repository at Yucca Mountain. Nevada is the response of the host rock to the emplacement of heat-generating waste. The thermal perturbation of the rock mass has implications regarding the structural, hydrologic. and geochemical performance of the potential repository. The phenomenological coupling of many of these performance aspects makes repository thermal modeling a difficult task. For many of the more complex, coupled models, it is often necessary to reduce the geometry of the potential repository to a smeared heat-source approximation. Such simplifications have impacts on induced thermal profiles that in turn may influence other predicted responses through one- or two-way thermal couplings. The effect of waste employment layout on host-rock thermal was chosen as the primary emphasis of this study. Using a consistent set of modeling and input assumptions, far-field thermal response predictions made for discrete-source as well as plate source approximations of the repository geometry. Input values used in the simulations are consistent with a design-basis a real power density (APD) of 80 kW/acre as would be achieved assuming a 2010 emplacement start date, a levelized receipt schedule, and a limitation on available area as published in previous design studies. It was found that edge effects resulting from general repository layout have a significant influence on the shapes and extents of isothermal profiles, and should be accounted for in far-field modeling efforts

  6. High energy near- and far-field ptychographic tomography at the ESRF

    Science.gov (United States)

    da Silva, Julio C.; Haubrich, Jan; Requena, Guillermo; Hubert, Maxime; Pacureanu, Alexandra; Bloch, Leonid; Yang, Yang; Cloetens, Peter

    2017-09-01

    In high-resolution tomography, one needs high-resolved projections in order to reconstruct a high-quality 3D map of a sample. X-ray ptychography is a robust technique which can provide such high-resolution 2D projections taking advantage of coherent X-rays. This technique was used in the far-field regime for a fair amount of time, but it can now also be implemented in the near-field regime. In both regimes, the technique enables not only high-resolution imaging, but also high sensitivity to the electron density of the sample. The combination with tomography makes 3D imaging possible via ptychographic X-ray computed tomography (PXCT), which can provide a 3D map of the complex-valued refractive index of the sample. The extension of PXCT to X-ray energies above 15 keV is challenging, but it can allow the imaging of object opaque to lower energy. We present here the implementation and developments of high-energy near- and far-field PXCT at the ESRF.

  7. Adaptive acoustic energy delivery to near and far fields using foldable, tessellated star transducers

    Science.gov (United States)

    Zou, Chengzhe; Harne, Ryan L.

    2017-05-01

    Methods of guiding acoustic energy arbitrarily through space have long relied on digital controls to meet performance needs. Yet, more recent attention to adaptive structures with unique spatial configurations has motivated mechanical signal processing (MSP) concepts that may not be subjected to the same functional and performance limitations as digital acoustic beamforming counterparts. The periodicity of repeatable structural reconfiguration enabled by origami-inspired tessellated architectures turns attention to foldable platforms as frameworks for MSP development. This research harnesses principles of MSP to study a tessellated, star-shaped acoustic transducer constituent that provides on-demand control of acoustic energy guiding via folding-induced shape reconfiguration. An analytical framework is established to probe the roles of mechanical and acoustic geometry on the far field directivity and near field focusing of sound energy. Following validation by experiments and verification by simulations, parametric studies are undertaken to uncover relations between constituent topology and acoustic energy delivery to arbitrary points in the free field. The adaptations enabled by folding of the star-shaped transducer reveal capability for restricting sound energy to angular regions in the far field while also introducing means to modulate sound energy by three orders-of-magnitude to locations near to the transducer surface. In addition, the modeling philosophy devised here provides a valuable approach to solve general sound radiation problems for foldable, tessellated acoustic transducer constituents of arbitrary geometry.

  8. Metal/Polymer Based Stretchable Antenna for Constant Frequency Far-Field Communication in Wearable Electronics

    KAUST Repository

    Hussain, Aftab M.

    2015-10-06

    Body integrated wearable electronics can be used for advanced health monitoring, security, and wellness. Due to the complex, asymmetric surface of human body and atypical motion such as stretching in elbow, finger joints, wrist, knee, ankle, etc. electronics integrated to body need to be physically flexible, conforming, and stretchable. In that context, state-of-the-art electronics are unusable due to their bulky, rigid, and brittle framework. Therefore, it is critical to develop stretchable electronics which can physically stretch to absorb the strain associated with body movements. While research in stretchable electronics has started to gain momentum, a stretchable antenna which can perform far-field communications and can operate at constant frequency, such that physical shape modulation will not compromise its functionality, is yet to be realized. Here, a stretchable antenna is shown, using a low-cost metal (copper) on flexible polymeric platform, which functions at constant frequency of 2.45 GHz, for far-field applications. While mounted on a stretchable fabric worn by a human subject, the fabricated antenna communicated at a distance of 80 m with 1.25 mW transmitted power. This work shows an integration strategy from compact antenna design to its practical experimentation for enhanced data communication capability in future generation wearable electronics.

  9. A Broadband UHF Tag Antenna For Near-Field and Far-Field RFID Communications

    Directory of Open Access Journals (Sweden)

    M. Dhaouadi

    2014-12-01

    Full Text Available The paper deals with the design of passive broadband tag antenna for Ultra-High Frequency (UHF band. The antenna is intended for both near and far fields Radio Frequency Identification (RFID applications. The meander dipole tag antenna geometry modification is designed for frequency bandwidth increasing. The measured bandwidth of the proposed broadband Tag antenna is more than 140 MHz (820–960 MHz, which can cover the entire UHF RFID band. A comparison between chip impedance of datasheet and the measured chip impedance has been used in our simulations. The proposed progressive meandered antenna structure, with an overall size of 77 mm × 14 mm × 0.787 mm, produces strong and uniform magnetic field distribution in the near-field zone. The antenna impedance is matched to common UHF chips in market simply by tuning its capacitive and inductive values since a perfect matching is required in the antenna design in order to enhance the near and the far field communications. Measurements confirm that the designed antenna exhibits good performance of Tag identification for both near-field and far-field UHF RFID applications.

  10. Far-field thermomechanical response of argillaceous rock to emplacement of a nuclear-waste repository

    International Nuclear Information System (INIS)

    McVey, D.F.; Thomas, R.K.; Lappin, A.R.

    1980-08-01

    Before heat-producing wastes can be emplaced safely in any argillaceous rock, it will be necessary to understand the far-field thermal and thermomechanical response of this rock to waste emplacement. This report presents the results of a first series of calculations aimed at estimating the far-field response of argillite to waste emplacement. Because the thermal and mechanical properties of argillite are affected by its content of expandable clay, its behavior is briefly compared and contrasted with that of a shale having the same matrix thermal properties, but containing no expandable clay. Under this assumption, modeled temperatures are the same for the two rock types at equivalent power densities and reflect the large dependence of in-situ temperatures on both initial power density and waste type. Thermomechanical calculations indicate that inclusion of contraction behavior of expandable clays in the assumed argillite thermal expansion behavior results, in some cases, in generation of a large zone in and near the repository that has undergone volumetric contraction but is surrounded by uniformly compressive stresses. Information available to date indicates that this contraction would likely result in locally increased fluid permeability and decreased in-situ thermal conductivity, but might well be advantageous as regards radionuclide retention, because of the increased surface area within the contracted zone. Assumption of continuous and positive expansion behavior for the shale eliminates the near-repository contraction and tensional zones, but results in near-surface tensional zones directly above the repository

  11. Modelling of far-field gas migration from a deep radioactive waste repository

    International Nuclear Information System (INIS)

    Rodwell, W.R.; Nash, P.J.

    1992-01-01

    In assessing the post-closure safety of a deep radioactive waste repository, it is necessary to show that gas generated within the repository can migrate away, through the far-field geology, without affecting repository safety. This paper discusses the contribution of various mechanisms to gas migration through the far field; for example, diffusion of dissolved gas versus gas-phase movement, and bubble flow versus formation of a connected gas stream. It outlines different approaches to modelling gas movement from a repository, with simple semi-analytical models furnishing physical insights into the factors controlling gas migration in the absence of directly applicable experimental data, and more comprehensive numerical computations allowing the exploration of more detailed behaviour when appropriate data is obtained. If gas can induce groundwater movement, this could accelerate the transport of water-borne contaminants. Processes by which this could occur are noted, and the current status of work on possible effects of gas migration on groundwater movement in fractured hard rocks is indicated. 14 refs., 4 figs

  12. A sensitivity study of the thermomechanical far-field model of Yucca Mountain

    International Nuclear Information System (INIS)

    Brandshaug, T.

    1991-04-01

    A sensitivity study has been conducted investigating the predicted thermal and mechanical behavior of the far-field model of a proposed nuclear waste repository at Yucca Mountain. The model input parameters and phenomena that have been investigated include areal power density, thermal conductivity, specific heat capacity, material density, pore water boiling, stratigraphic and topographic simplifications Young's modulus, Poisson's ratio, coefficient of thermal expansion, in situ stress, rock matrix cohesion, rock matrix angle of internal friction, rock joint cohesion, and rock joint angle of internal friction. Using the range in values currently associated with these parameters, predictions were obtained for rock temperatures, stresses, matrix failure, and joint activity throughout the far-field model. Results show that the range considered for the areal power density has the most significant effect on the predicted rock temperatures. The range considered for the in situ stress has the most significant effect on the prediction of rock stresses and factors-of-safety for the matrix and joints. Predictions of matrix and joint factors-of-safety are also influenced significantly by the use of stratigraphic and topographic simplifications. 16 refs., 75 figs., 13 tabs

  13. Modelling far field pacing for terminating spiral waves pinned to ischaemic heterogeneities in cardiac tissue

    Science.gov (United States)

    Boccia, E.; Luther, S.

    2017-01-01

    In cardiac tissue, electrical spiral waves pinned to a heterogeneity can be unpinned (and eventually terminated) using electric far field pulses and recruiting the heterogeneity as a virtual electrode. While for isotropic media the process of unpinning is much better understood, the case of an anisotropic substrate with different conductivities in different directions still needs intensive investigation. To study the impact of anisotropy on the unpinning process, we present numerical simulations based on the bidomain formulation of the phase I of the Luo and Rudy action potential model modified due to the occurrence of acute myocardial ischaemia. Simulating a rotating spiral wave pinned to an ischaemic heterogeneity, we compare the success of sequences of far field pulses in the isotropic and the anisotropic case for spirals still in transient or in steady rotation states. Our results clearly indicate that the range of pacing parameters resulting in successful termination of pinned spiral waves is larger in anisotropic tissue than in an isotropic medium. This article is part of the themed issue ‘Mathematical methods in medicine: neuroscience, cardiology and pathology’. PMID:28507234

  14. Safety assessment of hypothetical near surface disposal at Serpong site: far-field modeling

    International Nuclear Information System (INIS)

    Lubis, E.; D Mallants; G Volckraert

    2001-01-01

    The far field modeling of radionuclide disposed at Serpong site was carried out based on the hydrogeological data. The simulation of radionuclide in the groundwater was calculated by the PORFLOW computer code. The groundwater simulation was done for 2 cases. In the first case the conductivity of soil layer at Serpong site contains of two layers and in the second case just contains of one layer. The results of the first case, indicated that the flow calculations show that depending on the location of the disposal site, radionuclides that are released from the repository may either show up in the nearby Cisalak creek or in Cisadane river. The results of the second case indicated that the local flow system exist. This means that all radionuclides that migrate out of the repository will appear in the Cisalak creek. The transport time for radionuclides with a low retardation factor in lateric clay soil is around 10 years for a travel of 200 m distance

  15. Electromagnetic signatures of far-field gravitational radiation in the 1 + 3 approach

    International Nuclear Information System (INIS)

    Chua, Alvin J K; Cañizares, Priscilla; Gair, Jonathan R

    2015-01-01

    Gravitational waves (GWs) from astrophysical sources can interact with background electromagnetic fields, giving rise to distinctive and potentially detectable electromagnetic signatures. In this paper, we study such interactions for far-field gravitational radiation using the 1 + 3 approach to relativity. Linearized equations for the electromagnetic field on perturbed Minkowski space are derived and solved analytically. The inverse Gertsenshteĭn conversion of GWs in a static electromagnetic field is rederived, and the resultant electromagnetic radiation is shown to be significant for highly magnetized pulsars in compact binary systems. We also obtain a variety of nonlinear interference effects for interacting gravitational and electromagnetic waves, although wave–wave resonances previously described in the literature are absent when the electric–magnetic self-interaction is taken into account. The fluctuation and amplification of electromagnetic energy flux as the GW strength increases towards the gravitational–electromagnetic frequency ratio is a possible signature of gravitational radiation from extended astrophysical sources. (paper)

  16. New evidence for "far-field" Holocene sea level oscillations and links to global climate records

    Science.gov (United States)

    Leonard, N. D.; Welsh, K. J.; Clark, T. R.; Feng, Y.-x.; Pandolfi, J. M.; Zhao, J.-x.

    2018-04-01

    Rising sea level in the coming century is of significant concern, yet predicting relative sea level change in response to eustatic sea level variability is complex. Potential analogues are provided by the recent geological past but, until recently, many sea level reconstructions have been limited to millennial scale interpretations due to age uncertainties and paucity in proxy derived records. Here we present a sea level history for the tectonically stable "far-field" Great Barrier Reef, Australia, derived from 94 high precision uranium-thorium dates of sub-fossil coral microatolls. Our results provide evidence for at least two periods of relative sea level instability during the Holocene. These sea level oscillations are broadly synchronous with Indo-Pacific negative sea surface temperature anomalies, rapid global cooling events and glacial advances. We propose that the pace and magnitude of these oscillations are suggestive of eustatic/thermosteric processes operating in conjunction with regional climatic controls.

  17. Far-Field Voice Activity Detection and Its Applications in Adverse Acoustic Environments

    DEFF Research Database (Denmark)

    Petsatodis, Theodoros

    2012-01-01

    -sided Gamma distribution. The increased adaptability of the system along with the encapsulated adaptive threshold allows the system to perform remarkably under adverse complex phenomena. Following recent technological trends, of incorporating microphone arrays in numerous commercial applications (eg. mobile...... phones, VOIP terminals) and research environments (smart rooms), a multiple microphone VAD is also considered. The system processes signals captured by far-field sensors in order to integrate spatial information in addition to the frequency content available at a single sensor. The core of the system......-modality of speech production, a simple visual-VAD is also developed to examine performance enhancement when fusing audio and video information. In the final part of the work, applications of VAD in the context of integration with other signal processing systems are also considered. Performance benefits of combining...

  18. Full control of far-field radiation via photonic integrated circuits decorated with plasmonic nanoantennas.

    Science.gov (United States)

    Sun, Yi-Zhi; Feng, Li-Shuang; Bachelot, Renaud; Blaize, Sylvain; Ding, Wei

    2017-07-24

    We theoretically develop a hybrid architecture consisting of photonic integrated circuit and plasmonic nanoantennas to fully control optical far-field radiation with unprecedented flexibility. By exploiting asymmetric and lateral excitation from silicon waveguides, single gold nanorod and cascaded nanorod pair can function as component radiation pixels, featured by full 2π phase coverage and nanoscale footprint. These radiation pixels allow us to design scalable on-chip devices in a wavefront engineering fashion. We numerically demonstrate beam collimation with 30° out of the incident plane and nearly diffraction limited divergence angle. We also present high-numerical-aperture (NA) beam focusing with NA ≈0.65 and vector beam generation (the radially-polarized mode) with the mode similarity greater than 44%. This concept and approach constitutes a designable optical platform, which might be a future bridge between integrated photonics and metasurface functionalities.

  19. Advances in the study of far-field phenomena affecting repository performance

    International Nuclear Information System (INIS)

    Tsang, C.F.

    1991-01-01

    Studies of far-field phenomena affecting repository performance have focussed on the role of fractures and other heterogeneities in the potential transport of radioactive solutes from the repository to the biosphere. The present paper summarizes two recent advances in the subject: the channeling model for the understanding and analysis tracer transport in variable-aperture fractures and the modeling of coupled thermo-hydro-mechanical processes in geologic formation around a repository. The paper concludes with remarks on the need for duality in the approach to performance assessment. One line of the duality is fundamental studies and the other, goal-oriented assessment to satisfy regulatory requirements. 15 refs., 10 figs., 1 tab

  20. Femtosecond refractive-index tailoring of an optical fiber and phase retrieval from far-field measurements

    DEFF Research Database (Denmark)

    Savolainen, Juha-Matti; Grüner-Nielsen, Lars; Kristensen, Poul

    2013-01-01

    A refractive-index change is written inside an optical fiber close to the end face by femtosecond laser light. The induced phase change is measured by analyzing the far-field intensity profiles before and after the irradiation.......A refractive-index change is written inside an optical fiber close to the end face by femtosecond laser light. The induced phase change is measured by analyzing the far-field intensity profiles before and after the irradiation....

  1. Phase-Based Adaptive Estimation of Magnitude-Squared Coherence Between Turbofan Internal Sensors and Far-Field Microphone Signals

    Science.gov (United States)

    Miles, Jeffrey Hilton

    2015-01-01

    A cross-power spectrum phase based adaptive technique is discussed which iteratively determines the time delay between two digitized signals that are coherent. The adaptive delay algorithm belongs to a class of algorithms that identifies a minimum of a pattern matching function. The algorithm uses a gradient technique to find the value of the adaptive delay that minimizes a cost function based in part on the slope of a linear function that fits the measured cross power spectrum phase and in part on the standard error of the curve fit. This procedure is applied to data from a Honeywell TECH977 static-engine test. Data was obtained using a combustor probe, two turbine exit probes, and far-field microphones. Signals from this instrumentation are used estimate the post-combustion residence time in the combustor. Comparison with previous studies of the post-combustion residence time validates this approach. In addition, the procedure removes the bias due to misalignment of signals in the calculation of coherence which is a first step in applying array processing methods to the magnitude squared coherence data. The procedure also provides an estimate of the cross-spectrum phase-offset.

  2. Radionuclide transport in the repository near-field and far-field

    International Nuclear Information System (INIS)

    Poteri, A.; Nordman, H.; Pulkkanen, V.-M.; Smith, P.

    2014-01-01

    This report is a background report of the TURVA-2012 safety case report 'Assessment of Radionuclide Release Scenarios for the Repository System'. This report gives a comprehensive account of the modelling of radionuclide release from a defective canister and the subsequent migration to the surface groundwater system. The focus of this report is in the radionuclide migration both in the repository near-field and in the repository far-field. Radionuclide releases from the canister and migration through the repository near-field and far-field have also been analysed in the probabilistic sensitivity analysis based on the Monte Carlo simulation method. Those simulations are discussed in a separate report by Cormenzana. Calculation cases are derived from three different types of scenarios: (i) The base scenario that assumes a single initially defective canister located in a cautiously selected canister position, i.e. selecting the failed canister location such that radionuclide release and transport properties are conservative compared to the statistics over all canister locations. Migration processes and parameter values follow the most likely lines of evolution. Repository safety functions are assumed to perform according to the design basis. Calculation cases defined in the Assessment of Radionuclide Release Scenarios report are also supplemented by additional calculation cases that are aimed to study variability between different DFN realisations (additional BS-ALL cases), longitudinal dispersion (BS-RC-ld cases) and alternative realisations of the transport classes along the release paths (BS-RC-tc cases), (ii) Variant scenarios that study declined performance of the repository safety functions. These include enhanced corrosion failure and degradation of the buffer under variant geochemical conditions (iii) Disturbance scenarios that analyse influences of unlikely events on the radionuclide release and migration. Analysis of the variant and disturbance scenarios

  3. MARFA user's manual: Migration analysis of radionuclides in the far field

    International Nuclear Information System (INIS)

    Painter, S.; Mancillas, J.

    2013-12-01

    The computer code Migration Analysis of Radionuclides in the Far Field (MARFA) uses a particle-based Monte Carlo method to simulate the transport of radionuclides in a sparsely fractured geological medium. The algorithm uses non-interacting particles to represent packets of radionuclide mass. These particles are moved through the system according to rules that mimic the underlying physical transport and retention processes. The physical processes represented in MARFA include advection, longitudinal dispersion, Fickian diffusion into an infinite or finite rock matrix, equilibrium sorption, decay, and in-growth. Because the algorithm uses non-interacting particles, the transport and retention processes are limited to those that depend linearly on radionuclide concentration. Multiple non-branching decay chains of arbitrary length are supported, as is full heterogeneity in the transport and retention properties. Two variants of the code are provided. These two versions differ in how particles are routed through the computational domain. In MARFA 3.2.3, transport is assumed to occur along a set of trajectories or pathways that originate at radionuclide source locations. The trajectories are intended to represent the movement of hypothetical, advectively transported groundwater tracers and are typically calculated by pathline tracing in a discrete fracture network flow code. The groundwater speed and retention properties along each pathway may change in time, but the pathway trajectories are fixed. MARFA 3.3.1 allows the transport effects of changing flow directions to be represented by abandoning the fixed pathways and performing node routing within MARFA. (orig.)

  4. Probabilistic tsunami hazard assessment at Seaside, Oregon, for near-and far-field seismic sources

    Science.gov (United States)

    Gonzalez, F.I.; Geist, E.L.; Jaffe, B.; Kanoglu, U.; Mofjeld, H.; Synolakis, C.E.; Titov, V.V.; Areas, D.; Bellomo, D.; Carlton, D.; Horning, T.; Johnson, J.; Newman, J.; Parsons, T.; Peters, R.; Peterson, C.; Priest, G.; Venturato, A.; Weber, J.; Wong, F.; Yalciner, A.

    2009-01-01

    The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk. Copyright 2009 by the American Geophysical Union.

  5. Reduced-rank approximations to the far-field transform in the gridded fast multipole method

    Science.gov (United States)

    Hesford, Andrew J.; Waag, Robert C.

    2011-05-01

    The fast multipole method (FMM) has been shown to have a reduced computational dependence on the size of finest-level groups of elements when the elements are positioned on a regular grid and FFT convolution is used to represent neighboring interactions. However, transformations between plane-wave expansions used for FMM interactions and pressure distributions used for neighboring interactions remain significant contributors to the cost of FMM computations when finest-level groups are large. The transformation operators, which are forward and inverse Fourier transforms with the wave space confined to the unit sphere, are smooth and well approximated using reduced-rank decompositions that further reduce the computational dependence of the FMM on finest-level group size. The adaptive cross approximation (ACA) is selected to represent the forward and adjoint far-field transformation operators required by the FMM. However, the actual error of the ACA is found to be greater than that predicted using traditional estimates, and the ACA generally performs worse than the approximation resulting from a truncated singular-value decomposition (SVD). To overcome these issues while avoiding the cost of a full-scale SVD, the ACA is employed with more stringent accuracy demands and recompressed using a reduced, truncated SVD. The results show a greatly reduced approximation error that performs comparably to the full-scale truncated SVD without degrading the asymptotic computational efficiency associated with ACA matrix assembly.

  6. Analysis of the steel braced frames equipped with ADAS devices under the far field records

    Directory of Open Access Journals (Sweden)

    Mahmoud Bayat

    Full Text Available The usefulness of supplementary energy dissipation devices is now quite well-known in earthquake structural engineering for reducing the earthquake-induced response of structural systems. The seismic behavior of structures with supplemental ADAS devices is concerned in this study. In this paper, the ratio of the hysteretic energy to input energy is compared in different structural systems. The main purpose of this paper is to evaluate the behavior of structures equipped with yielding dampers (ADAS, located in far fields based on energy concepts. In order to optimize their seismic behavior, the codes and solutions are also presented. Three cases including five, ten and fifteen-story three-bay Concentric Braced Frames (CBF with and without ADAS were selected. The PERFORM 3D.V4 software along with three earthquake records (Northridge, Imperial Valley and Tabas is used for nonlinear time history analysis and the conclusions are drawn upon energy criterion. The effect of PGA variation and height of the frames are also considered in the study. Finally, to increase the energy damping ability and reduce the destructive effects in structures on an earthquake event, so that a great amount of induced energy is damped and destruction of the structure is prevented as much as possible by using ADAS dampers.

  7. Paleogene volcanism in Central Afghanistan: Possible far-field effect of the India-Eurasia collision

    Science.gov (United States)

    Motuza, Gediminas; Šliaupa, Saulius

    2017-10-01

    A volcanic-sedimentary succession of Paleogene age is exposed in isolated patches at the southern margin of the Tajik block in the Ghor province of Central Afghanistan. The volcanic rocks range from basalts and andesites to dacites, including adakites. They are intercalated with sedimentary rocks deposited in shallow marine environments, dated biostratigraphically as Paleocene-Eocene. This age corresponds to the age of the Asyābēd andesites located in the western Ghor province estimated by the 40Ar/39Ar method as 54 Ma. The magmatism post-dates the Cimmerian collision between the Tajik block (including the Band-e-Bayan block) and the Farah Rod block located to the south. While the investigated volcanic rocks apparently bear geochemical signatures typical to an active continental margin environment, it is presumed that the magmatism was related to rifting processes most likely initiated by far-field tectonics caused by the terminal collision of the Indian plate with Eurasia (Najman et al., 2017). This event led to the dextral movement of the Farah Rod block, particularly along Hari Rod (Herat) fault system, resulting in the development of a transtensional regime in the proximal southern margin of the Tajik block and giving rise to a rift basin where marine sediments were interbedded with pillow lavas intruded by sheeted dyke series.

  8. Reconstruction of far-field tsunami amplitude distributions from earthquake sources

    Science.gov (United States)

    Geist, Eric L.; Parsons, Thomas E.

    2016-01-01

    The probability distribution of far-field tsunami amplitudes is explained in relation to the distribution of seismic moment at subduction zones. Tsunami amplitude distributions at tide gauge stations follow a similar functional form, well described by a tapered Pareto distribution that is parameterized by a power-law exponent and a corner amplitude. Distribution parameters are first established for eight tide gauge stations in the Pacific, using maximum likelihood estimation. A procedure is then developed to reconstruct the tsunami amplitude distribution that consists of four steps: (1) define the distribution of seismic moment at subduction zones; (2) establish a source-station scaling relation from regression analysis; (3) transform the seismic moment distribution to a tsunami amplitude distribution for each subduction zone; and (4) mix the transformed distribution for all subduction zones to an aggregate tsunami amplitude distribution specific to the tide gauge station. The tsunami amplitude distribution is adequately reconstructed for four tide gauge stations using globally constant seismic moment distribution parameters established in previous studies. In comparisons to empirical tsunami amplitude distributions from maximum likelihood estimation, the reconstructed distributions consistently exhibit higher corner amplitude values, implying that in most cases, the empirical catalogs are too short to include the largest amplitudes. Because the reconstructed distribution is based on a catalog of earthquakes that is much larger than the tsunami catalog, it is less susceptible to the effects of record-breaking events and more indicative of the actual distribution of tsunami amplitudes.

  9. Scintillation has minimal impact on far-field Bennett-Brassard 1984 protocol quantum key distribution

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Jeffrey H. [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2011-09-15

    The effect of scintillation, arising from propagation through atmospheric turbulence, on the sift and error probabilities of a quantum key distribution (QKD) system that uses the weak-laser-pulse version of the Bennett-Brassard 1984 (BB84) protocol is evaluated. Two earth-space scenarios are examined: satellite-to-ground and ground-to-satellite transmission. Both lie in the far-field power-transfer regime. This work complements previous analysis of turbulence effects in near-field terrestrial BB84 QKD [J. H. Shapiro, Phys. Rev. A 67, 022309 (2003)]. More importantly, it shows that scintillation has virtually no impact on the sift and error probabilities in earth-space BB84 QKD, something that has been implicitly assumed in prior analyses for that application. This result contrasts rather sharply with what is known for high-speed laser communications over such paths, in which deep, long-lived scintillation fades present a major challenge to high-reliability operation.

  10. Optimal placement of active braces by using PSO algorithm in near- and far-field earthquakes

    Science.gov (United States)

    Mastali, M.; Kheyroddin, A.; Samali, B.; Vahdani, R.

    2016-03-01

    One of the most important issues in tall buildings is lateral resistance of the load-bearing systems against applied loads such as earthquake, wind and blast. Dual systems comprising core wall systems (single or multi-cell core) and moment-resisting frames are used as resistance systems in tall buildings. In addition to adequate stiffness provided by the dual system, most tall buildings may have to rely on various control systems to reduce the level of unwanted motions stemming from severe dynamic loads. One of the main challenges to effectively control the motion of a structure is limitation in distributing the required control along the structure height optimally. In this paper, concrete shear walls are used as secondary resistance system at three different heights as well as actuators installed in the braces. The optimal actuator positions are found by using optimized PSO algorithm as well as arbitrarily. The control performance of buildings that are equipped and controlled using the PSO algorithm method placement is assessed and compared with arbitrary placement of controllers using both near- and far-field ground motions of Kobe and Chi-Chi earthquakes.

  11. Mixed Far-Field and Near-Field Source Localization Algorithm via Sparse Subarrays

    Directory of Open Access Journals (Sweden)

    Jiaqi Song

    2018-01-01

    Full Text Available Based on a dual-size shift invariance sparse linear array, this paper presents a novel algorithm for the localization of mixed far-field and near-field sources. First, by constructing a cumulant matrix with only direction-of-arrival (DOA information, the proposed algorithm decouples the DOA estimation from the range estimation. The cumulant-domain quarter-wavelength invariance yields unambiguous estimates of DOAs, which are then used as coarse references to disambiguate the phase ambiguities in fine estimates induced from the larger spatial invariance. Then, based on the estimated DOAs, another cumulant matrix is derived and decoupled to generate unambiguous and cyclically ambiguous estimates of range parameter. According to the coarse range estimation, the types of sources can be identified and the unambiguous fine range estimates of NF sources are obtained after disambiguation. Compared with some existing algorithms, the proposed algorithm enjoys extended array aperture and higher estimation accuracy. Simulation results are given to validate the performance of the proposed algorithm.

  12. Modeling of Coastal Effluent Transport: an Approach to Linking of Far-field and Near-field Models

    International Nuclear Information System (INIS)

    Yang, Zhaoqing; Khangaonkar, Tarang P.

    2008-01-01

    One of the challenges in effluent transport modeling in coastal tidal environments is the proper calculation of initial dilution in connection with the far-field transport model. In this study, an approach of external linkage of far-field and near-field effluent transport models is presented, and applied to simulate the effluent transport in the Port Angeles Harbor, Washington in the Strait of Juan de Fuca. A near-field plume model was used to calculate the effluent initial dilution and a three-dimensional (3-D) hydrodynamic model was developed to simulate the tidal circulation and far-field effluent transport in the Port Angeles Harbor. In the present study, the hydrodynamic model was driven by tides and surface winds. Observed water surface elevation and velocity data were used to calibrate the model over a period covering the neap-spring tidal cycle. The model was also validated with observed surface drogue trajectory data. The model successfully reproduced the tidal dynamics in the study area and good agreements between model results and observed data were obtained. This study demonstrated that the linkage between the near-field and far-field models in effluent transport modeling can be achieved through iteratively adjusting the model grid sizes such that the far-field modeled dilution ratio and effluent concentration in the effluent discharge model grid cell match the concentration calculated by the near-field plume model

  13. Far-Field Effects of Large Earthquakes on South Florida's Confined Aquifer

    Science.gov (United States)

    Voss, N. K.; Wdowinski, S.

    2012-12-01

    The similarity between a seismometer and a well hydraulic head record during the passage of a seismic wave has long been documented. This is true even at large distances from earthquake epicenters. South Florida lacks a dense seismic array but does contain a comparably dense network of monitoring wells. The large spatial distribution of deep monitoring wells in South Florida provides an opportunity to study the variance of aquifer response to the passage of seismic waves. We conducted a preliminary study of hydraulic head data, provided by the South Florida Water Management District, from 9 deep wells in South Florida's confined Floridian Aquifer in response to 27 main shock events (January 2010- April 2012) with magnitude 6.9 or greater. Coseismic hydraulic head response was observed in 7 of the 27 events. In order to determine what governs aquifer response to seismic events, earthquake parameters were compared for the 7 positive events. Seismic energy density (SED), an empirical relationship between distance and magnitude, was also used to compare the relative energy between the events at each well site. SED is commonly used as a parameter for establishing thresholds for hydrologic events in the near and intermediate fields. Our analysis yielded a threshold SED for well response in South Florida as 8 x 10-3 J m-3, which is consistent with other studies. Deep earthquakes, with SED above this threshold, did not appear to trigger hydraulic head oscillations. The amplitude of hydraulic head oscillations had no discernable relationship to SED levels. Preliminary results indicate a need for a modification of the SED equation to better accommodate depth in order to be of use in the study of hydrologic response in the far field. We plan to conduct a more comprehensive study incorporating a larger subset (~60) of wells in South Florida in order to further examine the spatial variance of aquifers to the passing of seismic waves as well as better confine the relationship

  14. Whistler wave propagation in the antenna near and far fields in the Naval Research Laboratory Space Physics Simulation Chamber

    International Nuclear Information System (INIS)

    Blackwell, David D.; Walker, David N.; Amatucci, William E.

    2010-01-01

    In previous papers, early whistler propagation measurements were presented [W. E. Amatucci et al., IEEE Trans. Plasma Sci. 33, 637 (2005)] as well as antenna impedance measurements [D. D. Blackwell et al., Phys. Plasmas 14, 092106 (2007)] performed in the Naval Research Laboratory Space Physics Simulation Chamber (SPSC). Since that time there have been major upgrades in the experimental capabilities of the laboratory in the form of improvement of both the plasma source and antennas. This has allowed access to plasma parameter space that was previously unattainable, and has resulted in measurements that provide a significantly clearer picture of whistler propagation in the laboratory environment. This paper presents some of the first whistler experimental results from the upgraded SPSC. Whereas previously measurements were limited to measuring the cyclotron resonance cutoff and elliptical polarization indicative of the whistler mode, now it is possible to experimentally plot the dispersion relation itself. The waves are driven and detected using balanced dipole and loop antennas connected to a network analyzer, which measures the amplitude and phase of the wave in two dimensions (r and z). In addition the frequency of the signals is also swept over a range of several hundreds of megahertz, providing a comprehensive picture of the near and far field antenna radiation patterns over a variety of plasma conditions. The magnetic field is varied from a few gauss to 200 G, with the density variable over at least 3 decades from 10 7 to 10 10 cm -3 . The waves are shown to lie on the dispersion surface for whistler waves, with observation of resonance cones in agreement with theoretical predictions. The waves are also observed to propagate without loss of amplitude at higher power, a result in agreement with previous experiments and the notion of ducted whistlers.

  15. MARFA version 3.2.2 user's manual: migration analysis of radionuclides in the far field

    International Nuclear Information System (INIS)

    Painter, Scott; Mancillas, James

    2009-12-01

    The computer code Migration Analysis of Radionuclides in the Far Field (MARFA) uses a particle-based Monte Carlo method to simulate the transport of radionuclides in a sparsely fractured geological medium. Transport in sparsely fractured rock is of interest because this medium may serve as a barrier to migration of radionuclides to the accessible environment. The physical processes represented in MARFA include advection, longitudinal dispersion, Fickian diffusion into an infinite or finite rock matrix, equilibrium sorption, decay, and in-growth. Multiple non-branching decay chains of arbitrary length are supported. This document describes the technical basis and input requirements for MARFA Version 3.2.2. MARFA Version 3.2 included new capabilities to accommodate transient flow velocities and sorption parameters, which are assumed to be piecewise constant in time. Version 3.2.1 was a minor change from Version 3.2 to allow a more convenient input format for sorption information. New capabilities in Version 3.2.2 include an option to specify a non-zero start time for the simulation, an optional input parameter that decreases the amount of retention within a single fracture because of flow channeling, and an alternative method for sampling the radionuclide source. MARFA uses the particle on random streamline segment algorithm /Painter et al. 2006/, a Monte Carlo algorithm combining time-domain random walk methods with pathway stochastic simulation. The algorithm uses non-interacting particles to represent packets of radionuclide mass. These particles are moved through the system according to rules that mimic the underlying physical transport and retention processes. The set of times required for particles to pass through the geological barrier are then used to reconstruct discharge rates (mass or activity basis). Because the algorithm uses non-interacting particles, the transport and retention processes are limited to those that depend linearly on radionuclide

  16. Testing the near field/far field model performance for prediction of particulate matter emissions in a paint factory

    DEFF Research Database (Denmark)

    Koivisto, A.J.; Jensen, A.C.Ø.; Levin, Marcus

    2015-01-01

    A Near Field/Far Field (NF/FF) model is a well-accepted tool for precautionary exposure assessment but its capability to estimate particulate matter (PM) concentrations is not well studied. The main concern is related to emission source characterization which is not as well defined for PM emitters...

  17. Analytical expressions for group delay in the far field from an optical fiber having an arbitrary index profile

    OpenAIRE

    Danielsen, Per Lander

    1981-01-01

    A general and efficient model for optical fibers with a few modes and arbitrary index profiles is established. The model yields a solution of the vectorial wave equation and analytical expressions for the group delay and the far field. Convergence tests have shown that the dispersion can be calculated with an accuracy better than 0.2 ps/(km . nm).

  18. Analytical expressions for group delay in the far field from an optical fiber having an arbitrary index profile

    DEFF Research Database (Denmark)

    Danielsen, Per Lander

    1981-01-01

    A general and efficient model for optical fibers with a few modes and arbitrary index profiles is established. The model yields a solution of the vectorial wave equation and analytical expressions for the group delay and the far field. Convergence tests have shown that the dispersion can...

  19. Efficient EBE treatment of the dynamic far-field in non-linear FE soil-structure interaction analyses

    NARCIS (Netherlands)

    Crouch, R.S.; Bennett, T.

    2000-01-01

    This paper presents results and observations from the use of a rigorous method of treating the dynamic far-field as part of a non-linear FE analysis. The technique de-veloped by Wolf and Song (referred to as the Scaled Boundary Finite-Element Method) is incorporated into a 3-D time-domain analysis

  20. Assessment of reflectivity of noise barriers in the far field – QUIESST method compared to traditional approach

    NARCIS (Netherlands)

    Roo, F. de

    2013-01-01

    The sound reflectivity of noise barriers elements is one of the major acoustic product characteristics. Traditionally this property was tested in reverberation rooms according to EN 1793-1 and the results were used to predict the effect of sound reflections in the far field. As in many cases these

  1. Far-field divergence of a vectorial plane wave diffracted by a circular aperture from the vectorial structure

    International Nuclear Information System (INIS)

    Zhou Guo-Quan

    2011-01-01

    Based on the vectorial structure of an electromagnetic wave, the analytical and concise expressions for the TE and TM terms of a vectorial plane wave diffracted by a circular aperture are derived in the far-field. The expressions of the energy flux distributions of the TE term, the TM term and the diffracted plane wave are also presented. The ratios of the power of the TE and TM terms to that of the diffracted plane wave are examined in the far-field. In addition, the far-field divergence angles of the TE term, the TM term and the diffracted plane wave, which are related to the energy flux distribution, are investigated. The different energy flux distributions of the TE and TM terms result in the discrepancy of their divergence angles. The influences of the linearly polarized angle and the radius of the circular aperture on the far-field divergence angles of the TE term, the TM term and the diffracted plane wave are discussed in detail. This research may promote the recognition of the optical propagation through a circular aperture. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  2. On-axis and far-field sound radiation from resilient flat and dome-shaped radiators

    NARCIS (Netherlands)

    Aarts, R.M.; Janssen, A.J.E.M.

    2009-01-01

    On-axis and far-field series expansions are developed for the sound pressure due to an arbitrary, circular symmetric velocity distribution on a flat radiator in an infinite baffle. These expansions are obtained by expanding the velocity distributions in terms of orthogonal polynomials

  3. The UK contribution to the CEC PACOMA Project: far-field modelling of radioactive waste disposal in clay

    International Nuclear Information System (INIS)

    Winters, K.H.; Jackson, C.P.; Clark, C.M.

    1990-06-01

    This document describes a study of groundwater flow and radionuclide migration in the far field of a hypothetical repository located in the clay beneath Harwell Laboratory. The work forms part of the assessment of the radiological impact of disposal in a clay formation, carried out as the UK contribution to the CEC PACOMA project. (Author)

  4. Analytical research of vibration and far-field acoustic radiation of cylindrical shell immersed at finite depth

    Directory of Open Access Journals (Sweden)

    GUO Wenjie

    2017-08-01

    Full Text Available Aiming at the current lack of analytical research concerning the cylindrical shell-flow field coupling vibration and sound radiation system under the influence of a free surface, this paper proposes an analytical method which solves the vibration response and far-field acoustic radiation of a finite cylindrical shell immersed at a finite depth. Based on the image method and Graf addition theorem, the analytical expression of the fluid velocity potential can be obtained, then combined with the energy functional of the variation method to deduce the shell-liquid coupling vibration equation, which can in turn solve the forced vibration response. The research shows that, compared with an infinite fluid, a free surface can increase at the same order of resonance frequency; but as the depth of immersion gradually increases, the mean square vibration velocity tends to become the same as that in an infinite fluid. Compared with numerical results from Nastran software, this shows that the present method is accurate and reliable, and has such advantages as a simple method and a small amount of calculation. The far-field radiated pressure can be obtained by the vibration response using the Fourier transformation and stationary phase method. The results indicate that the directivity and volatility of the far-field acoustic pressure of a cylindrical shell is similar to that of an acoustical dipole due to the free surface. However, the far-field acoustic pressure is very different from the vibration characteristics, and will not tend to an infinite fluid as the submerging depth increases. Compared with the numerical method, the method in this paper is simpler and has a higher computational efficiency. It enables the far-field acoustic radiation of an underwater cylindrical shell to be predicted quickly under the influence of external incentives and the free surface, providing guiding significance for acoustic research into the half space structure vibration

  5. J-85 jet engine noise measured in the ONERA S1 wind tunnel and extrapolated to far field

    Science.gov (United States)

    Soderman, Paul T.; Julienne, Alain; Atencio, Adolph, Jr.

    1991-01-01

    Noise from a J-85 turbojet with a conical, convergent nozzle was measured in simulated flight in the ONERA S1 Wind Tunnel. Data are presented for several flight speeds up to 130 m/sec and for radiation angles of 40 to 160 degrees relative to the upstream direction. The jet was operated with subsonic and sonic exhaust speeds. A moving microphone on a 2 m sideline was used to survey the radiated sound field in the acoustically treated, closed test section. The data were extrapolated to a 122 m sideline by means of a multiple-sideline source-location method, which was used to identify the acoustic source regions, directivity patterns, and near field effects. The source-location method is described along with its advantages and disadvantages. Results indicate that the effects of simulated flight on J-85 noise are significant. At the maximum forward speed of 130 m/sec, the peak overall sound levels in the aft quadrant were attentuated approximately 10 dB relative to sound levels of the engine operated statically. As expected, the simulated flight and static data tended to merge in the forward quadrant as the radiation angle approached 40 degrees. There is evidence that internal engine or shock noise was important in the forward quadrant. The data are compared with published predictions for flight effects on pure jet noise and internal engine noise. A new empirical prediction is presented that relates the variation of internally generated engine noise or broadband shock noise to forward speed. Measured near field noise extrapolated to far field agrees reasonably well with data from similar engines tested statically outdoors, in flyover, in a wind tunnel, and on the Bertin Aerotrain. Anomalies in the results for the forward quadrant and for angles above 140 degrees are discussed. The multiple-sideline method proved to be cumbersome in this application, and it did not resolve all of the uncertainties associated with measurements of jet noise close to the jet. The

  6. Determination of femtosecond-laser-induced refractive-index changes in an optical fiber from far-field measurements

    DEFF Research Database (Denmark)

    Savolainen, Juha-Matti; Grüner-Nielsen, Lars; Kristensen, Poul

    2014-01-01

    A new method for direct writing of localized, circularly symmetric refractive-index changes in optical fibers with a femtosecond laser is demonstrated. The refractive-index changes are characterized using a novel approach employing comparison of numerical simulations to the measured far......-field profiles of unmodified and modified fibers. From the analysis, a negative refractive-index change of −0.015 0.005 within a radius of 0.6 0.1 μm is determined....

  7. Liquid microdroplet as an optical component to achieve imaging of 100 nm nanostructures on a far-field microscope

    Science.gov (United States)

    Hou, Beibei; Zhang, Luning

    2018-05-01

    We demonstrate that placing liquid microdroplets on a sample surface enables probing of the evanescent wave, thus having super-resolution capability on a far-field optical microscope. A simple method to form diiodomethane (CH2I2) liquid microdroplets with diameters of 10–90 μm in water is proposed. These microdroplets can be used to image various nanostructured samples with a feature size of about 100 nm under white-light illumination.

  8. An Exact Line Integral Representation of the Physical Optics Far Field from Plane PEC Scatterers Illuminnated by Hertzian Dipoles

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Meincke, Peter; Jørgensen, Erik

    2003-01-01

    We derive a line integral representation of the physical optics scattered far field that yields the exact same result as the conventional surface radiation integral. This representation applies to a perfectly electrically conducting plane scatterer illuminated by electric or magnetic Hertzian...... dipoles. The source and observation points can take on almost arbitrary positions. To illustrate the exactness and efficiency of the new line integral, numerical comparisons with the conventional surface radiation integral are carried out....

  9. The UK contribution to the CEC PACOMA Project: far-field modelling of radioactive waste disposal in clay

    International Nuclear Information System (INIS)

    Winters, K.H.; Jackson, C.P.; Clark, C.M.

    1990-06-01

    PACOMA (Performance Assessment of Confinement for Medium-active and Alpha-bearing wastes) is a multinational project supported as part of the Commission of the European Community's R and D programme on radioactive waste management and storage. The aim of the project is to assess the radiological impact of deep geological disposal of intermediate level waste in three different types of geological formation: clay, granite and salt. The contribution of AEA Technology is a study of the groundwater flow and radionuclide migration in the far field. This report describes the far-field modelling. The three-stratum model used in previous hydrogeological studies of the Harwell region is used as a basis for the far-field two-dimensional section through the chalk, clay and Corallian strata underlying Harwell. Each of the three layers is represented as a continuous porous medium with an assumed best-estimate value of permeability, and the groundwater flow is predicted by solving the Darcy equations over the complete section using the NAMMU finite-element code. Two-dimensional transport equations describing the migration of radionuclides in the groundwater are solved, also using NAMMU. The fluxes of radionuclides normal to the surface of the water table are calculated as a function of space and time. The most significant result of the calculations of radionuclide transport through the geosphere is the prediction of multiple pathways for radionuclide movement in the geological strata, and hence multiple release points into the biosphere. Particular attention is paid in the study to the performance and appropriation of the numerical methods and the physical models used for the far-field calculations. (author)

  10. Action-at-a-distance metamaterials : Distributed local actuation through far-field global forces

    NARCIS (Netherlands)

    Hedayati, R.; Mirzaali, M. J.; Vergani, L.; Zadpoor, A.A.

    2018-01-01

    Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of "action-at-a-distance" metamaterials where a specific pattern of

  11. A new method for incoherent combining of far-field laser beams based on multiple faculae recognition

    Science.gov (United States)

    Ye, Demao; Li, Sichao; Yan, Zhihui; Zhang, Zenan; Liu, Yuan

    2018-03-01

    Compared to coherent beam combining, incoherent beam combining can complete the output of high power laser beam with high efficiency, simple structure, low cost and high thermal damage resistance, and it is easy to realize in engineering. Higher target power is achieved by incoherent beam combination which using technology of multi-channel optical path correction. However, each channel forms a spot in the far field respectively, which cannot form higher laser power density with low overlap ratio of faculae. In order to improve the combat effectiveness of the system, it is necessary to overlap different faculae that improve the target energy density. Hence, a novel method for incoherent combining of far-field laser beams is present. The method compromises piezoelectric ceramic technology and evaluation algorithm of faculae coincidence degree which based on high precision multi-channel optical path correction. The results show that the faculae recognition algorithm is low-latency(less than 10ms), which can meet the needs of practical engineering. Furthermore, the real time focusing ability of far field faculae is improved which was beneficial to the engineering of high-energy laser weapon or other laser jamming systems.

  12. Near-field/far-field array manifold of an acoustic vector-sensor near a reflecting boundary.

    Science.gov (United States)

    Wu, Yue Ivan; Lau, Siu-Kit; Wong, Kainam Thomas

    2016-06-01

    The acoustic vector-sensor (a.k.a. the vector hydrophone) is a practical and versatile sound-measurement device, with applications in-room, open-air, or underwater. It consists of three identical uni-axial velocity-sensors in orthogonal orientations, plus a pressure-sensor-all in spatial collocation. Its far-field array manifold [Nehorai and Paldi (1994). IEEE Trans. Signal Process. 42, 2481-2491; Hawkes and Nehorai (2000). IEEE Trans. Signal Process. 48, 2981-2993] has been introduced into the technical field of signal processing about 2 decades ago, and many direction-finding algorithms have since been developed for this acoustic vector-sensor. The above array manifold is subsequently generalized for outside the far field in Wu, Wong, and Lau [(2010). IEEE Trans. Signal Process. 58, 3946-3951], but only if no reflection-boundary is to lie near the acoustic vector-sensor. As for the near-boundary array manifold for the general case of an emitter in the geometric near field, the far field, or anywhere in between-this paper derives and presents that array manifold in terms of signal-processing mathematics. Also derived here is the corresponding Cramér-Rao bound for azimuth-elevation-distance localization of an incident emitter, with the reflected wave shown to play a critical role on account of its constructive or destructive summation with the line-of-sight wave. The implications on source localization are explored, especially with respect to measurement model mismatch in maximum-likelihood direction finding and with regard to the spatial resolution between coexisting emitters.

  13. Compiling Holocene RSL databases from near- to far-field regions: proxies, difficulties and possible solutions

    Science.gov (United States)

    Vacchi, M.; Horton, B.; Mann, T.; Engelhart, S. E.; Rovere, A.; Nikitina, D.; Bender, M.; Roy, K.; Peltier, W. R.

    2017-12-01

    Reconstructions of relative sea level (RSL) have implications for investigation of crustal movements, calibration of earth rheology models and the reconstruction of ice sheets. In recent years, efforts were made to create RSL databases following a standardized methodology. These regional databases provide a framework for developing our understanding of the primary mechanisms of RSL change since the Last Glacial Maximum and a long-term baseline against which to gauge changes in sea level during the 20th century and forecasts for the 21st. We report here the results of recently compiled databases in very different climatic and geographic contexts that are the northeastern Canadian coast, the Mediterranean Sea as well as the southeastern Asiatic region. Our re-evaluation of sea-level indicators from geological and archaeological investigations have yielded more than 3000 RSL data-points mainly from salt and freshwater wetlands or adjacent estuarine sediment, isolation basins, beach ridges, fixed biological indicators, beachrocks as well as coastal archaeological structures. We outline some of the inherent difficulties, and potential solutions to analyse sea-level data in such different depositional environments. In particular, we discuss problems related with the definition of standardized indicative meaning, and with the re-evaluation of old radiocarbon samples. We further address complex tectonics influences and the framework to compare such large variability of RSL data-points. Finally we discuss the implications of our results for the patterns of glacio-isostatic adjustment in these regions.

  14. The far field heating effects of a radioactive waste depository in hard rock

    International Nuclear Information System (INIS)

    Hodgkinson, D.P.; Bourke, P.J.

    1978-01-01

    Fission product heating of the rock surrounding a depository for high level radioactive waste, will result in high temperatures and high thermal gradients over distances of several hundred metres for many centuries. The consequent thermal expansion of the rock leads to stresses which could alter the fracture pattern and therefore the permeability of the rock. These problems are assessed by considering an idealised model of a depository for which analytic solutions to the temperature and stress fields are derived. A related problem is that any water present in the fissures will tend to rise because of its decrease in density on heating. If the water had previously leached away some of the radionuclides in the waste, then this convective transport constitutes a possible leakage path back to the biosphere. For the low permeabilities expected at a depository site, it is possible to linearise the resulting equations and derive analytic solutions for the flow velocities. This procedure has been carried out for the idealised depository model, in order to estimate the magnitude of these effects

  15. Simulation of Far-Field Superresolution Fluorescence Imaging with Two-Color One-Photon Excitation of Reversible Photoactivatable Protein

    International Nuclear Information System (INIS)

    Wang Chen; Qiao Ling-Ling; Mao Zheng-Le

    2011-01-01

    We propose to achieve far-field super-resolution imaging by using offset two-color one-photon (2C1P) excitation of reversible photoactivatable fluorescence proteins. Due to the distinctive photoswitching performance of the proteins, such as dronpa, the fluorescence emission will only come from the overlapped region of activation beam and excitation beam. The analysis solution of rate equation shows that the resolution of offset 2C1P microscope is 'engineered' by laser power of excitation and activation beams and the power ratio between them. Superior lateral and transverse resolution is theoretically demonstrated compared with conventional fluorescence scanning microscopy. (fundamental areas of phenomenology(including applications))

  16. Suppression of sound radiation to far field of near-field acoustic communication system using evanescent sound field

    Science.gov (United States)

    Fujii, Ayaka; Wakatsuki, Naoto; Mizutani, Koichi

    2016-01-01

    A method of suppressing sound radiation to the far field of a near-field acoustic communication system using an evanescent sound field is proposed. The amplitude of the evanescent sound field generated from an infinite vibrating plate attenuates exponentially with increasing a distance from the surface of the vibrating plate. However, a discontinuity of the sound field exists at the edge of the finite vibrating plate in practice, which broadens the wavenumber spectrum. A sound wave radiates over the evanescent sound field because of broadening of the wavenumber spectrum. Therefore, we calculated the optimum distribution of the particle velocity on the vibrating plate to reduce the broadening of the wavenumber spectrum. We focused on a window function that is utilized in the field of signal analysis for reducing the broadening of the frequency spectrum. The optimization calculation is necessary for the design of window function suitable for suppressing sound radiation and securing a spatial area for data communication. In addition, a wide frequency bandwidth is required to increase the data transmission speed. Therefore, we investigated a suitable method for calculating the sound pressure level at the far field to confirm the variation of the distribution of sound pressure level determined on the basis of the window shape and frequency. The distribution of the sound pressure level at a finite distance was in good agreement with that obtained at an infinite far field under the condition generating the evanescent sound field. Consequently, the window function was optimized by the method used to calculate the distribution of the sound pressure level at an infinite far field using the wavenumber spectrum on the vibrating plate. According to the result of comparing the distributions of the sound pressure level in the cases with and without the window function, it was confirmed that the area whose sound pressure level was reduced from the maximum level to -50 dB was

  17. A Newton method for a simultaneous reconstruction of an interface and a buried obstacle from far-field data

    International Nuclear Information System (INIS)

    Zhang, Haiwen; Zhang, Bo

    2013-01-01

    This paper is concerned with the inverse problem of scattering of time-harmonic acoustic waves from a penetrable and a buried obstacle. By introducing a related transmission scattering problem, a Newton iteration method is proposed to simultaneously reconstruct both the penetrable interface and the buried obstacle inside from far-field data. The main feature of our method is that we do not need to know the type of boundary conditions on the buried obstacle. In particular, the boundary condition on the buried obstacle can also be determined simultaneously by the method. Finally, numerical examples using multi-frequency data are carried out to illustrate the effectiveness of our method. (paper)

  18. Quantifying the intrinsic amount of fabrication disorder in photonic-crystal waveguides from optical far-field intensity measurements

    DEFF Research Database (Denmark)

    Garcia-Fernandez, Pedro David; Javadi, Alisa; Nielsen, Henri Thyrrestrup

    2013-01-01

    Residual disorder due to fabrication imperfections has important impact in nanophotonics where it may degrade device performance by increasing radiation loss or spontaneously trap light by Anderson localization. We propose and demonstrate experimentally a method of quantifying the intrinsic amount...... of disorder in state-of-the-art photonic-crystal waveguides from far-field measurements of the Anderson-localized modes. This is achieved by comparing the spectral range where Anderson localization is observed to numerical simulations, and the method offers sensitivity down to 1nm....

  19. Far field optical nanoscopy: How far can you go in nanometric characterization without resolving all the details?

    International Nuclear Information System (INIS)

    Montgomery, Paul C.; Serio, Bruno; Anstotz, Freddy; Montaner, Denis

    2013-01-01

    In the development of nanomaterials and biomaterials, new characterization techniques are required that overcome the challenges presented by the increasing dimensional ratio between the different entities to be studied and the growing complexity introduced by the use of heterogeneous materials and technologies. Diffraction limited far field optical nanoscopy techniques are receiving growing interest because of their ability to detect nanometer structures over very large fields and at high speed. We present a classification scheme of the different types of optical nanoscopy techniques. In particular, we highlight four categories of far field diffraction limited techniques based on increasing the contrast, measuring the phase, using deconvolution and using nano-markers. We demonstrate that by increasing the power of detectability, observability or measurability, a wealth of information concerning nanometric structures becomes available even though all the lateral details may not be resolved. For example, it is possible to determine the presence, the structure and orientation of nanostructures, to measure their density, position and 2D and 3D distribution and to measure nanometric surface roughness in bulk materials, surfaces, nano-layers, soft matter and cells. These techniques conserve all the advantages associated with classical imaging such as real time imaging, non-invasiveness, non-destructiveness and ease of use.

  20. Evaluating the far-field sound of a turbulent jet with one-way Navier-Stokes equations

    Science.gov (United States)

    Pickering, Ethan; Rigas, Georgios; Towne, Aaron; Colonius, Tim

    2017-11-01

    The one-way Navier-Stokes (OWNS) method has shown promising ability to predict both near field coherent structures (i.e. wave packets) and far field acoustics of turbulent jets while remaining computationally efficient through implementation of a spatial marching scheme. Considering the speed and relative accuracy of OWNS, a predictive model for various jet configurations may be conceived and applied for noise control. However, there still remain discrepancies between OWNS and large eddy simulation (LES) databases which may be linked to the previous neglect of nonlinear forcing. Therefore, to better predict wave packets and far field acoustics, this study investigates the effect of nonlinear forcing terms derived from high-fidelity LES databases. The results of the nonlinear forcings are evaluated for several azimuthal modes and frequencies, as well as compared to LES derived acoustics using spectral proper orthogonal decomposition (SPOD). This research was supported by the Department of Defense (DoD) through the Office of Naval Research (Grant No. N00014-16-1-2445) and the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

  1. Description of the transport mechanisms and pathways in the far field of a KBS-3 type repository

    International Nuclear Information System (INIS)

    Elert, M.; Neretnieks, I.

    1992-04-01

    The main purpose of this document is to serve as a reference document for the far field radionuclide transport description within SKB 91. A conceptual description of far field transport in crystalline rock is given together with a discussion of the application of the stream tube concept. In this concept the transport in a complex tree-dimensional flow field is divided into a number of imaginary tubes which are modelled independently. The stream tube concept is used as the basis for the radionuclide calculations in SKB 91. Different mathematical models for calculating the transport of radionuclides in fractured rock are compared: advection dispersion models, channeling models and network models. In the SKB 91 project a dual-porosity continuum model based on the one dimensional advection-dispersion equation taking into account matrix diffusion, sorption in the rock matrix and radioactive chain decay. Furthermore, the data needed for the transport models is discussed and recommended ranges and central values are given. (42 refs.) (au)

  2. Acoustic inverse scattering using topological derivative of far-field measurements-based L2 cost functionals

    International Nuclear Information System (INIS)

    Bellis, Cédric; Bonnet, Marc; Cakoni, Fioralba

    2013-01-01

    Originally formulated in the context of topology optimization, the concept of topological derivative has also proved effective as a qualitative inversion tool for a wave-based identification of finite-sized objects. This approach remains, however, largely based on a heuristic interpretation of the topological derivative, whereas most other qualitative approaches to inverse scattering are backed by a mathematical justification. As an effort toward bridging this gap, this study focuses on a topological derivative approach applied to the L 2 -norm of the misfit between far-field measurements. Either an inhomogeneous medium or a finite number of point-like scatterers are considered, using either the Born approximation or a full-scattering model. Topological derivative-based imaging functionals are analyzed using a suitable factorization of the far-field operator, for each of the considered cases, in order to characterize their behavior and assess their ability to reconstruct the unknown scatterer(s). Results include the justification of the usual sign heuristic underpinning the method for (i) the Born approximation and (ii) full-scattering models limited to moderately strong scatterers. Semi-analytical and numerical examples are presented. Within the chosen framework, the topological derivative approach is finally discussed and compared to other well-known qualitative methods. (paper)

  3. A compartment model for nuclide release calculation in the near-and far-field of a HLW repository

    International Nuclear Information System (INIS)

    Lee, Youn Myoung; Hwang, Yong Soo; Kang, Chul Hyung; Hahn, Pil Soo

    2004-01-01

    The HLW-relevant R and D program for disposal of high-level radioactive waste has been carried out at Korea Atomic Energy Research Institute (KAERI) since early 1997, from which a conceptual Korea Reference Repository System for direct disposal of nuclear spent fuel is to be introduced by the end of 2007. A preliminary reference geologic repository concept considering such established criteria and requirements as spent fuel and generic site characteristics in Korea was roughly envisaged in 2003. Not only to demonstrate how much a reference repository is safe in the generic point of view with several possible scenarios and cases associated with a preliminary repository concept by conducting calculations for nuclide release and transport in the near - and far - field components of the repository, even though sufficient information has not been available that much yet, but also to show a appropriate methodology by which both a generic and site - specific safety assessment could be performed for further in - depth development of Korea reference repository concept, nuclide release calculation study for various nuclide release cases is mandatory. To this end a similar study done and yet limited for the near - field release case has been extended to the case including far - field system by introducing some more geosphere compartments. Advective and longitudinal dispersive nuclide transports along the fracture with matrix diffusion as well as several retention mechanisms and nuclide ingrowth has been added

  4. An optical super-microscope for far-field, real-time imaging beyond the diffraction limit.

    Science.gov (United States)

    Wong, Alex M H; Eleftheriades, George V

    2013-01-01

    Optical microscopy suffers from a fundamental resolution limitation arising from the diffractive nature of light. While current solutions to sub-diffraction optical microscopy involve combinations of near-field, non-linear and fine scanning operations, we hereby propose and demonstrate the optical super-microscope (OSM) - a superoscillation-based linear imaging system with far-field working and observation distances - which can image an object in real-time and with sub-diffraction resolution. With our proof-of-principle prototype we report a point spread function with a spot size clearly reduced from the diffraction limit, and demonstrate corresponding improvements in two-point resolution experiments. Harnessing a new understanding of superoscillations, based on antenna array theory, our OSM achieves far-field, sub-diffraction optical imaging of an object without the need for fine scanning, data post-processing or object pre-treatment. Hence the OSM can be used in a wide variety of imaging applications beyond the diffraction limit, including real-time imaging of moving objects.

  5. An Application of Artificial Intelligence for the Joint Estimation of Amplitude and Two-Dimensional Direction of Arrival of Far Field Sources Using 2-L-Shape Array

    Directory of Open Access Journals (Sweden)

    Fawad Zaman

    2013-01-01

    Full Text Available An easy and efficient approach, based on artificial intelligence technique, is proposed to jointly estimate the amplitude, elevation, and azimuth angles of far field sources impinging on 2-L-shape array. In these proposed artificial intelligence techniques, the metaheuristics based on genetic algorithm and simulated annealing are used as global optimizers assisted with rapid local version of pattern search for optimization of the adaptive parameters. The performance metric is employed on a fitness evaluation function depending on mean square error which is optimum and requires single snapshot to converge. The proposed approaches are easy to understand, and simple to implement; the genetic algorithm specifically hybridized with pattern search generates fairly good results. The comparison of the given schemes is carried out with 1-L-shape array, as well as, with parallel-shape array and is found to be in good agreement in terms of accuracy, convergence rate, computational complexity, and mean square error. The effectiveness and efficiency of the given schemes are examined through Monte Carlo simulations and their inclusive statistical analysis.

  6. Apertureless near-field/far-field CW two-photon microscope for biological and material imaging and spectroscopic applications.

    Science.gov (United States)

    Nowak, Derek B; Lawrence, A J; Sánchez, Erik J

    2010-12-10

    We present the development of a versatile spectroscopic imaging tool to allow for imaging with single-molecule sensitivity and high spatial resolution. The microscope allows for near-field and subdiffraction-limited far-field imaging by integrating a shear-force microscope on top of a custom inverted microscope design. The instrument has the ability to image in ambient conditions with optical resolutions on the order of tens of nanometers in the near field. A single low-cost computer controls the microscope with a field programmable gate array data acquisition card. High spatial resolution imaging is achieved with an inexpensive CW multiphoton excitation source, using an apertureless probe and simplified optical pathways. The high-resolution, combined with high collection efficiency and single-molecule sensitive optical capabilities of the microscope, are demonstrated with a low-cost CW laser source as well as a mode-locked laser source.

  7. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    International Nuclear Information System (INIS)

    Stenhouse, M.J.; Miller, W.M.; Chapman, N.A.

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  8. Design and operation of an inexpensive far-field laser scanning microscope suitable for use in an undergraduate laboratory course

    Science.gov (United States)

    Pallone, Arthur; Hawk, Eric

    2013-03-01

    Scanning microscope applications span the science disciplines yet their costs limit their use at educational institutions. The basic concepts of scanning microscopy are simple. The microscope probe - whether it produces a photon, electron or ion beam - moves relative to the surface of the sample object. The beam interacts with the sample to produce a detected signal that depends on the desired property to be measured at the probe location on the sample. The microscope transforms the signal for output in a form desired by the user. Undergraduate students can easily construct a far-field laser scanning microscope that illustrates each of these principles from parts available at local electronics and hardware stores and use the microscope to explore properties of devices such as light dependent resistors and biological samples such as leaves. Students can record, analyze and interpret results using a computer and free software.

  9. Far-Field Tsunami Hazard Assessment Along the Pacific Coast of Mexico by Historical Records and Numerical Simulation

    Science.gov (United States)

    Ortiz-Huerta, Laura G.; Ortiz, Modesto; García-Gastélum, Alejandro

    2018-03-01

    Historical records of the Chile (22 May 1960), Alaska (27 March 1964), and Tohoku (11 March 2011) tsunamis recorded along the Pacific Coast of Mexico are used to investigate the goodness of far-field tsunami modeling using a focal mechanism consisting in a uniform slip distribution on large thrust faults around the Pacific Ocean. The Tohoku 2011 tsunami records recorded by Deep ocean Assessment and Reporting of Tsunami (DART) stations, and at coastal tide stations, were used to validate transoceanic tsunami models applicable to the harbors of Ensenada, Manzanillo, and Acapulco on the coast of Mexico. The amplitude resulting from synthetic tsunamis originated by M w 9.3 earthquakes around the Pacific varies from 1 to 2.5 m, depending on the tsunami origin region and on the directivity due to fault orientation and waveform modification by prominent features of sea bottom relief.

  10. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    Energy Technology Data Exchange (ETDEWEB)

    Stenhouse, M.J. [Monitor Scientific, LLC, Denver, CO (United States); Miller, W.M.; Chapman, N.A. [QuantiSci Ltd., Melton Mowbray (United Kingdom)

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  11. Spectral and far-field broadening due to stimulated rotational Raman scattering driven by the Nike krypton fluoride laser.

    Science.gov (United States)

    Weaver, James; Lehmberg, Robert; Obenschain, Stephen; Kehne, David; Wolford, Matthew

    2017-11-01

    Stimulated rotational Raman scattering (SRRS) in the ultraviolet region (λ=248  nm) has been observed at the Nike laser over extended propagation paths in air during high power operation. Although this phenomenon is not significant for standard operating configurations at Nike, broadening of the laser spectrum and far-field focal profiles has been observed once the intensity-path length product exceeds a threshold of approximately 1  TW/cm. This paper presents experimental results and a new theoretical evaluation of these effects. The observations suggest that significantly broader spectra can be achieved with modest degradation of the final focal distribution. These results point to a possible path for enhanced laser-target coupling with the reduction of laser-plasma instabilities due to broad laser bandwidth produced by the SRRS.

  12. Far-Field Tsunami Hazard Assessment Along the Pacific Coast of Mexico by Historical Records and Numerical Simulation

    Science.gov (United States)

    Ortiz-Huerta, Laura G.; Ortiz, Modesto; García-Gastélum, Alejandro

    2018-04-01

    Historical records of the Chile (22 May 1960), Alaska (27 March 1964), and Tohoku (11 March 2011) tsunamis recorded along the Pacific Coast of Mexico are used to investigate the goodness of far-field tsunami modeling using a focal mechanism consisting in a uniform slip distribution on large thrust faults around the Pacific Ocean. The Tohoku 2011 tsunami records recorded by Deep ocean Assessment and Reporting of Tsunami (DART) stations, and at coastal tide stations, were used to validate transoceanic tsunami models applicable to the harbors of Ensenada, Manzanillo, and Acapulco on the coast of Mexico. The amplitude resulting from synthetic tsunamis originated by M w 9.3 earthquakes around the Pacific varies from 1 to 2.5 m, depending on the tsunami origin region and on the directivity due to fault orientation and waveform modification by prominent features of sea bottom relief.

  13. Near Field and Far Field Effects in the Taguchi-Optimized Design of AN InP/GaAs-BASED Double Wafer-Fused Mqw Long-Wavelength Vertical-Cavity Surface-Emitting Laser

    Science.gov (United States)

    Menon, P. S.; Kandiah, K.; Mandeep, J. S.; Shaari, S.; Apte, P. R.

    Long-wavelength VCSELs (LW-VCSEL) operating in the 1.55 μm wavelength regime offer the advantages of low dispersion and optical loss in fiber optic transmission systems which are crucial in increasing data transmission speed and reducing implementation cost of fiber-to-the-home (FTTH) access networks. LW-VCSELs are attractive light sources because they offer unique features such as low power consumption, narrow beam divergence and ease of fabrication for two-dimensional arrays. This paper compares the near field and far field effects of the numerically investigated LW-VCSEL for various design parameters of the device. The optical intensity profile far from the device surface, in the Fraunhofer region, is important for the optical coupling of the laser with other optical components. The near field pattern is obtained from the structure output whereas the far-field pattern is essentially a two-dimensional fast Fourier Transform (FFT) of the near-field pattern. Design parameters such as the number of wells in the multi-quantum-well (MQW) region, the thickness of the MQW and the effect of using Taguchi's orthogonal array method to optimize the device design parameters on the near/far field patterns are evaluated in this paper. We have successfully increased the peak lasing power from an initial 4.84 mW to 12.38 mW at a bias voltage of 2 V and optical wavelength of 1.55 μm using Taguchi's orthogonal array. As a result of the Taguchi optimization and fine tuning, the device threshold current is found to increase along with a slight decrease in the modulation speed due to increased device widths.

  14. Estimating nitrogen loading and far-field dispersal potential from background sources and coastal finfish aquaculture: A simple framework and case study in Atlantic Canada

    Science.gov (United States)

    McIver, R.; Milewski, I.; Loucks, R.; Smith, R.

    2018-05-01

    Far-field nutrient impacts associated with finfish aquaculture have been identified as a topic of concern for regulators, managers, scientists, and the public for over two decades but disentangling aquaculture impacts from those caused by other natural and anthropogenic sources has impeded the development of monitoring metrics and management plans. We apply a bulk, steady-state nitrogen loading model (NLM) framework to estimate the annual input of Total Dissolved Nitrogen (TDN) from point and non-point sources to the watershed surrounding Port Mouton Bay, Nova Scotia (Canada). We then use the results of the NLM together with estimates of dissolved inorganic nitrogen (DIN) loading from a sea-cage trout farm in the Bay and progressive vector diagrams to illustrate potential patterns of DIN dispersal from the trout farm. Our estimated anthropogenic nitrogen contribution to Port Mouton Bay from all terrestrial and atmospheric sources is ∼211,703 kg TDN/year with atmospheric deposition accounting for almost all (98.6%). At a stocking level of ∼400,000 rainbow trout, the Port Mouton Bay sea-cage farm increases the annual anthropogenic TDN loading to the bay by 14.4% or 30,400 kg. Depending on current flow rates, nitrogen flux from the trout farm can be more than double the background concentrations of TDN near the farm site. Although it is unlikely that nitrogen loading from this single fish farm is saturating the DIN requirements of the entire bay, progressive vector diagrams suggest that the dispersal potential may be insufficient to mitigate potential symptoms of eutrophication associated with nitrogen fluxes. We present an accessible and user-friendly tool for managers to estimate baseline nutrient loading in relation to aquaculture and our use of progressive vector diagrams illustrate a practical and simple method for characterizing potential nutrient dispersal based on local conditions and spatial scales. Our study joins numerous studies which have highlighted

  15. Prediction and measurement of the electromagnetic environment of high-power medium-wave and short-wave broadcast antennas in far field.

    Science.gov (United States)

    Tang, Zhanghong; Wang, Qun; Ji, Zhijiang; Shi, Meiwu; Hou, Guoyan; Tan, Danjun; Wang, Pengqi; Qiu, Xianbo

    2014-12-01

    With the increasing city size, high-power electromagnetic radiation devices such as high-power medium-wave (MW) and short-wave (SW) antennas have been inevitably getting closer and closer to buildings, which resulted in the pollution of indoor electromagnetic radiation becoming worsened. To avoid such radiation exceeding the exposure limits by national standards, it is necessary to predict and survey the electromagnetic radiation by MW and SW antennas before constructing the buildings. In this paper, a modified prediction method for the far-field electromagnetic radiation is proposed and successfully applied to predict the electromagnetic environment of an area close to a group of typical high-power MW and SW wave antennas. Different from currently used simplified prediction method defined in the Radiation Protection Management Guidelines (H J/T 10. 3-1996), the new method in this article makes use of more information such as antennas' patterns to predict the electromagnetic environment. Therefore, it improves the prediction accuracy significantly by the new feature of resolution at different directions. At the end of this article, a comparison between the prediction data and the measured results is given to demonstrate the effectiveness of the proposed new method. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Assessment of exit block following pulmonary vein isolation: far-field capture masquerading as entrance without exit block.

    Science.gov (United States)

    Vijayaraman, Pugazhendhi; Dandamudi, Gopi; Naperkowski, Angela; Oren, Jess; Storm, Randle; Ellenbogen, Kenneth A

    2012-10-01

    Complete electrical isolation of pulmonary veins (PVs) remains the cornerstone of ablation therapy for atrial fibrillation. Entrance block without exit block has been reported to occur in 40% of the patients. Far-field capture (FFC) can occur during pacing from the superior PVs to assess exit block, and this may appear as persistent conduction from PV to left atrium (LA). To facilitate accurate assessment of exit block. Twenty consecutive patients with symptomatic atrial fibrillation referred for ablation were included in the study. Once PV isolation (entrance block) was confirmed, pacing from all the bipoles on the Lasso catheter was used to assess exit block by using a pacing stimulus of 10 mA at 2 ms. Evidence for PV capture without conduction to LA was necessary to prove exit block. If conduction to LA was noticed, pacing output was decreased until there was PV capture without conduction to LA or no PV capture was noted to assess for far-field capture in both the upper PVs. All 20 patients underwent successful isolation (entrance block) of all 76 (4 left common PV) veins: mean age 58 ± 9 years; paroxysmal atrial fibrillation 40%; hypertension 70%, diabetes mellitus 30%, coronary artery disease 15%; left ventricular ejection fraction 55% ± 10%; LA size 42 ± 11 mm. Despite entrance block, exit block was absent in only 16% of the PVs, suggesting persistent PV to LA conduction. FFC of LA appendage was noted in 38% of the left superior PVs. FFC of the superior vena cava was noted in 30% of the right superior PVs. The mean pacing threshold for FFC was 7 ± 4 mA. Decreasing pacing output until only PV capture (loss of FFC) is noted was essential to confirm true exit block. FFC of LA appendage or superior vena cava can masquerade as persistent PV to LA conduction. A careful assessment for PV capture at decreasing pacing output is essential to exclude FFC. Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  17. Field-survey report of the December 30, 2002, Stromboli (southern Italy) tsunami in the near- and far-field

    Science.gov (United States)

    Emergeo, W. G.; Maramai, A.; Graziani, L.; Tinti, S.; Armigliato, A.; Pagnoni, G.

    2003-04-01

    Since May 2002 Stromboli, one of the two active volcanoes in the Eolian Islands (southern Tyrrhenian sea), started a new explosive activity, initially characterized by gas and ash emission from the summit craters. By the end of November 2002 lava flows spread out both from the highest crater and the mid-slope of the Sciara del Fuoco, coupled with more intense gas and ash ejection. On December 30, 2002, a massive landslide detached from the height of about 650 m a.s.l. on the northwestern slope of the Stromboli island, involving also the submerged part of the volcanic edifice, producing a tsunami. This huge mass movement was also recorded by the INGV seismic stations installed on the island itself and at Panarea. Low seasonal frequentation of the island determined that only minor injuries were reported, otherwise the victim toll might have been soaring. In the following days, we organized a working group in order to perform a field survey of the tsunami effects in the near-field, including all the Eolian Islands. At the same time we planned a recognition in the far-field, along the coastline of the Campania, Calabria and Sicilia regions, where the effects of the tsunami were observed but not directly quantified. Visible material effects of the tsunami could be observed only along the coast of Stromboli island, inundated by a wave, with run-up heights locally up to several meters, that severely damaged many buildings located as far as 80-100 meters from the shoreline. The wave was strong enough to transport large lava boulders and either broken stone- or brick-wall for several meters up-slope and to lay down large patches of drifted sand. On all other Eolie islands and in the far field the effects of the sea wave were documented only through eyewitness accounts. To ensure a coherent collection of such accounts a standard interview form, based on the advises of the Intergovernmental Oceanographic Commission, was used. A databank of all observations, measurements

  18. Violin f-hole contribution to far-field radiation via patch near-field acoustical holography.

    Science.gov (United States)

    Bissinger, George; Williams, Earl G; Valdivia, Nicolas

    2007-06-01

    The violin radiates either from dual ports (f-holes) or via surface motion of the corpus (top+ribs+back), with no clear delineation between these sources. Combining "patch" near-field acoustical holography over just the f-hole region of a violin with far-field radiativity measurements over a sphere, it was possible to separate f-hole from surface motion contributions to the total radiation of the corpus below 2.6 kHz. A0, the Helmholtz-like lowest cavity resonance, radiated essentially entirely through the f-holes as expected while A1, the first longitudinal cavity mode with a node at the f-holes, had no significant f-hole radiation. The observed A1 radiation comes from an indirect radiation mechanism, induced corpus motion approximately mirroring the cavity pressure profile seen for violinlike bowed string instruments across a wide range of sizes. The first estimates of the fraction of radiation from the f-holes F(f) indicate that some low frequency corpus modes thought to radiate only via surface motion (notably the first corpus bending modes) had significant radiation through the f-holes, in agreement with net volume changes estimated from experimental modal analysis. F(f) generally trended lower with increasing frequency, following corpus mobility decreases. The f-hole directivity (top/back radiativity ratio) was generally higher than whole-violin directivity.

  19. Theoretical and numerical studies of crack initiation and propagation in rock masses under freezing pressure and far-field stress

    Directory of Open Access Journals (Sweden)

    Yongshui Kang

    2014-10-01

    Full Text Available Water-bearing rocks exposed to freezing temperature can be subjected to freeze–thaw cycles leading to crack initiation and propagation, which are the main causes of frost damage to rocks. Based on the Griffith theory of brittle fracture mechanics, the crack initiation criterion, propagation direction, and crack length under freezing pressure and far-field stress are analyzed. Furthermore, a calculation method is proposed for the stress intensity factor (SIF of the crack tip under non-uniformly distributed freezing pressure. The formulae for the crack/fracture propagation direction and length of the wing crack under freezing pressure are obtained, and the mechanism for coalescence of adjacent cracks is investigated. In addition, the necessary conditions for different coalescence modes of cracks are studied. Using the topology theory, a new algorithm for frost crack propagation is proposed, which has the capability to define the crack growth path and identify and update the cracked elements. A model that incorporates multiple cracks is built by ANSYS and then imported into FLAC3D. The SIFs are then calculated using a FISH procedure, and the growth path of the freezing cracks after several calculation steps is demonstrated using the new algorithm. The proposed method can be applied to rocks containing fillings such as detritus and slurry.

  20. Far-Field Lorenz-Mie Scattering in an Absorbing Host Medium: Theoretical Formalism and FORTRAN Program

    Science.gov (United States)

    Mishchenko, Michael I.; Yang, Ping

    2018-01-01

    In this paper we make practical use of the recently developed first-principles approach to electromagnetic scattering by particles immersed in an unbounded absorbing host medium. Specifically, we introduce an actual computational tool for the calculation of pertinent far-field optical observables in the context of the classical Lorenzâ€"Mie theory. The paper summarizes the relevant theoretical formalism, explains various aspects of the corresponding numerical algorithm, specifies the input and output parameters of a FORTRAN program available at https://www.giss.nasa.gov/staff/mmishchenko/Lorenz-Mie.html, and tabulates benchmark results useful for testing purposes. This public-domain FORTRAN program enables one to solve the following two important problems: (i) simulate theoretically the reading of a remote well-collimated radiometer measuring electromagnetic scattering by an individual spherical particle or a small random group of spherical particles; and (ii) compute the single-scattering parameters that enter the vector radiative transfer equation derived directly from the Maxwell equations.

  1. An Analysis of Mechanical Constraints when Using Superconducting Gravimeters for Far-Field Pre-Seismic Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Shyh-Chin Lan

    2011-01-01

    Full Text Available Pre-seismic gravity anomalies from records obtained at a 1 Hz sampling rate from superconducting gravimeters (SG around East Asia are analyzed. A comparison of gravity anomalies to the source parameters of associated earthquakes shows that the detection of pre-seismic gravity anomalies is constrained by several mechanical conditions of the seismic fault plane. The constraints of the far-field pre-seismic gravity amplitude perturbation were examined and the critical spatial relationship between the SG station and the epicenter precursory signal for detection was determined. The results show that: (1 the pre-seismic amplitude perturbation of gravity is inversely proportional to distance; (2 the transfer path from the epicenter to the SG station that crosses a tectonic boundary has a relatively low pre-seismic gravity anomaly amplitude; (3 the pre-seismic gravity perturbation amplitude is also affected by the attitude between the location of an SG station and the strike of the ruptured fault plane. The removal of typhoon effects and the selection of SG stations within a certain intersection angle to the strike of the fault plane are essential for obtaining reliable pre-seismic gravity anomaly results.

  2. Far-field Lorenz-Mie scattering in an absorbing host medium: Theoretical formalism and FORTRAN program

    Science.gov (United States)

    Mishchenko, Michael I.; Yang, Ping

    2018-01-01

    In this paper we make practical use of the recently developed first-principles approach to electromagnetic scattering by particles immersed in an unbounded absorbing host medium. Specifically, we introduce an actual computational tool for the calculation of pertinent far-field optical observables in the context of the classical Lorenz-Mie theory. The paper summarizes the relevant theoretical formalism, explains various aspects of the corresponding numerical algorithm, specifies the input and output parameters of a FORTRAN program available at https://www.giss.nasa.gov/staff/mmishchenko/Lorenz-Mie.html, and tabulates benchmark results useful for testing purposes. This public-domain FORTRAN program enables one to solve the following two important problems: (i) simulate theoretically the reading of a remote well-collimated radiometer measuring electromagnetic scattering by an individual spherical particle or a small random group of spherical particles; and (ii) compute the single-scattering parameters that enter the vector radiative transfer equation derived directly from the Maxwell equations.

  3. Improvement of the cruise performances of a wing by means of aerodynamic optimization. Validation with a Far-Field method

    Science.gov (United States)

    Jiménez-Varona, J.; Ponsin Roca, J.

    2015-06-01

    Under a contract with AIRBUS MILITARY (AI-M), an exercise to analyze the potential of optimization techniques to improve the wing performances at cruise conditions has been carried out by using an in-house design code. The original wing was provided by AI-M and several constraints were posed for the redesign. To maximize the aerodynamic efficiency at cruise, optimizations were performed using the design techniques developed internally at INTA under a research program (Programa de Termofluidodinámica). The code is a gradient-based optimizaa tion code, which uses classical finite differences approach for gradient computations. Several techniques for search direction computation are implemented for unconstrained and constrained problems. Techniques for geometry modifications are based on different approaches which include perturbation functions for the thickness and/or mean line distributions and others by Bézier curves fitting of certain degree. It is very e important to afford a real design which involves several constraints that reduce significantly the feasible design space. And the assessment of the code is needed in order to check the capabilities and the possible drawbacks. Lessons learnt will help in the development of future enhancements. In addition, the validation of the results was done using also the well-known TAU flow solver and a far-field drag method in order to determine accurately the improvement in terms of drag counts.

  4. A FDTD solution of scattering of laser beam with orbital angular momentum by dielectric particles: Far-field characteristics

    Science.gov (United States)

    Sun, Wenbo; Hu, Yongxiang; Weimer, Carl; Ayers, Kirk; Baize, Rosemary R.; Lee, Tsengdar

    2017-02-01

    Electromagnetic (EM) beams with orbital angular momentum (OAM) may have great potential applications in communication technology and in remote sensing of the Earth-atmosphere system and outer planets. Study of their interaction with optical lenses and dielectric or metallic objects, or scattering of them by particles in the Earth-atmosphere system, is a necessary step to explore the advantage of the OAM EM beams. In this study, the 3-dimensional (3D) scattered-field (SF) finite-difference time domain (FDTD) technique with the convolutional perfectly matched layer (CPML) absorbing boundary conditions (ABC) is applied to calculate the scattering of the purely azimuthal (the radial mode number is assumed to be zero) Laguerre-Gaussian (LG) beams with the OAM by dielectric particles. We found that for OAM beam's interaction with dielectric particles, the forward-scattering peak in the conventional phase function (P11) disappears, and light scattering peak occurs at a scattering angle of 15° to 45°. The disappearance of forward-scattering peak means that, in laser communications most of the particle-scattered noise cannot enter the receiver, thus the received light is optimally the original OAM-encoded signal. This feature of the OAM beam also implies that in lidar remote sensing of the atmospheric particulates, most of the multiple-scattering energy will be off lidar sensors, and this may result in an accurate profiling of particle layers in the atmosphere or in the oceans by lidar, or even in the ground when a ground penetration radar (GPR) with the OAM is applied. This far-field characteristics of the scattered OAM light also imply that the optical theorem, which is derived from plane-parallel wave scattering case and relates the forward scattering amplitude to the total cross section of the scatterer, is invalid for the scattering of OAM beams by dielectric particles.

  5. MARFA version 3.2.2 user's manual: migration analysis of radionuclides in the far field

    Energy Technology Data Exchange (ETDEWEB)

    Painter, Scott; Mancillas, James (Center for Nuclear Waste Regulatory Analyses, Southwest Research Inst., San Antonio, TX (United States))

    2009-12-15

    The computer code Migration Analysis of Radionuclides in the Far Field (MARFA) uses a particle-based Monte Carlo method to simulate the transport of radionuclides in a sparsely fractured geological medium. Transport in sparsely fractured rock is of interest because this medium may serve as a barrier to migration of radionuclides to the accessible environment. The physical processes represented in MARFA include advection, longitudinal dispersion, Fickian diffusion into an infinite or finite rock matrix, equilibrium sorption, decay, and in-growth. Multiple non-branching decay chains of arbitrary length are supported. This document describes the technical basis and input requirements for MARFA Version 3.2.2. MARFA Version 3.2 included new capabilities to accommodate transient flow velocities and sorption parameters, which are assumed to be piecewise constant in time. Version 3.2.1 was a minor change from Version 3.2 to allow a more convenient input format for sorption information. New capabilities in Version 3.2.2 include an option to specify a non-zero start time for the simulation, an optional input parameter that decreases the amount of retention within a single fracture because of flow channeling, and an alternative method for sampling the radionuclide source. MARFA uses the particle on random streamline segment algorithm/Painter et al. 2006/, a Monte Carlo algorithm combining time-domain random walk methods with pathway stochastic simulation. The algorithm uses non-interacting particles to represent packets of radionuclide mass. These particles are moved through the system according to rules that mimic the underlying physical transport and retention processes. The set of times required for particles to pass through the geological barrier are then used to reconstruct discharge rates (mass or activity basis). Because the algorithm uses non-interacting particles, the transport and retention processes are limited to those that depend linearly on radionuclide

  6. A FDTD solution of scattering of laser beam with orbital angular momentum by dielectric particles: Far-field characteristics

    International Nuclear Information System (INIS)

    Sun, Wenbo; Hu, Yongxiang; Weimer, Carl; Ayers, Kirk; Baize, Rosemary R.; Lee, Tsengdar

    2017-01-01

    Electromagnetic (EM) beams with orbital angular momentum (OAM) may have great potential applications in communication technology and in remote sensing of the Earth-atmosphere system and outer planets. Study of their interaction with optical lenses and dielectric or metallic objects, or scattering of them by particles in the Earth-atmosphere system, is a necessary step to explore the advantage of the OAM EM beams. In this study, the 3-dimensional (3D) scattered-field (SF) finite-difference time domain (FDTD) technique with the convolutional perfectly matched layer (CPML) absorbing boundary conditions (ABC) is applied to calculate the scattering of the purely azimuthal (the radial mode number is assumed to be zero) Laguerre–Gaussian (LG) beams with the OAM by dielectric particles. We found that for OAM beam's interaction with dielectric particles, the forward-scattering peak in the conventional phase function (P11) disappears, and light scattering peak occurs at a scattering angle of ~15° to 45°. The disappearance of forward-scattering peak means that, in laser communications most of the particle-scattered noise cannot enter the receiver, thus the received light is optimally the original OAM-encoded signal. This feature of the OAM beam also implies that in lidar remote sensing of the atmospheric particulates, most of the multiple-scattering energy will be off lidar sensors, and this may result in an accurate profiling of particle layers in the atmosphere or in the oceans by lidar, or even in the ground when a ground penetration radar (GPR) with the OAM is applied. This far-field characteristics of the scattered OAM light also imply that the optical theorem, which is derived from plane-parallel wave scattering case and relates the forward scattering amplitude to the total cross section of the scatterer, is invalid for the scattering of OAM beams by dielectric particles. - Highlights: • Scattering of orbital angular momentum (OAM) laser beam by dielectric

  7. 2.5D far-field diffraction tomography inversion scheme for GPR that takes into account the planar air-soil interface

    DEFF Research Database (Denmark)

    Meincke, Peter

    2001-01-01

    A new 2.5D inversion scheme is derived for fixed-offset ground penetrating radar (GPR) that takes into account the planar air-soil interface. The inversion scheme is based upon the first Born approximation and a far-field approximation of the dyadic Green function for a two-layer medium....

  8. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 3

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report summarises work funded by the Department of the Environment and UK Nirex Ltd in the area of sorption of radionuclides under the near-field and far-field conditions pertaining to the underground disposal of radioactive waste in the UK that was presented and discussed in Part I. The report also summarises comparable research undertaken overseas (presented in Part II). (author)

  9. A Line Integral Representation of the Physical Optics Far Field from Plane PEC Scatterers Illuminated by Electric or Magnetic Hertzian Dipoles

    DEFF Research Database (Denmark)

    Arslanagic, S.; Meincke, Peter; Jørgensen, E.

    2002-01-01

    We derive a line integral representation of the physical optics (PO) scattered far field that yields the exact same result as the conventional surface radiation integral. This representation applies to a perfectly electrically conducting plane scatterer illuminated by electric or magnetic Hertzian...... dipoles....

  10. Development of a numerical modelling tool for combined near field and far field wave transformations using a coupling of potential flow solvers

    DEFF Research Database (Denmark)

    Verbrugghe, Tim; Troch, Peter; Kortenhaus, Andreas

    2016-01-01

    Wave energy converters (WECs) need to be deployed in large numbers in an array layout in order to have a significant power production. Each WEC has an impact on the incoming wave field, diffracting, reflecting and radiating waves. Simulating the wave transformations within and around a WEC farm...... of a wave-structure interaction solver and a wave propagation model, both based on the potential flow theory. This paper discusses the coupling method and illustrates the functionality with a proof-of-concept. Additionally, a projection of the evolution of the numerical tool is given. It can be concluded...... is complex; it is difficult to simulate both near field and far field effects with a single numerical model, with relatively fast computing times. Within this research a numerical tool is developed to model near-field and far-field wave transformations caused by WECs. The tool is based on the coupling...

  11. Near-field and far-field modeling of scattered surface waves. Application to the apertureless scanning near-field optical microscopy

    International Nuclear Information System (INIS)

    Muller, J.; Parent, G.; Fumeron, S.; Jeandel, G.; Lacroix, D.

    2011-01-01

    The detection of surface waves through scanning near-field optical microscopy (SNOM) is a promising technique for thermal measurements at very small scales. Recent studies have shown that electromagnetic waves, in the vicinity of a scattering structure such as an atomic force microscopy (AFM) tip, can be scattered from near to far-field and thus detected. In the present work, a model based on the finite difference time domain (FDTD) method and the near-field to far-field (NFTFF) transformation for electromagnetic waves propagation is presented. This model has been validated by studying the electromagnetic field of a dipole in vacuum and close to a dielectric substrate. Then simulations for a tetrahedral tip close to an interface are presented and discussed.

  12. A review of the role of colloids in the release and transport of radionuclides in the near and far field. Pt. 3

    International Nuclear Information System (INIS)

    Tipping, E.; Higgo, J.J.W.

    1992-01-01

    The role of colloids in the release and transport of radionuclides in the near and far field is discussed and DOE and Nirex funded work is compared with relevant studies by other workers. Gaps in the DOE and Nirex programmes are identified and suggestions for further research are made. This is Part 3 of a three-part review. Part 1 reviews fundamental theory and DOE and Nirex funded work and Part 2 is a comprehensive bibliography (with abstracts). (Author)

  13. On the Seismic Response of Protected and Unprotected Middle-Rise Steel Frames in Far-Field and Near-Field Areas

    Directory of Open Access Journals (Sweden)

    Dora Foti

    2014-01-01

    Full Text Available Several steel moment-resisting framed buildings were seriously damaged during Northridge (1994; Kobe (1995; Kocaeli, Turkey (1999, earthquakes. Indeed, for all these cases, the earthquake source was located under the urban area and most victims were in near-field areas. In fact near-field ground motions show velocity and displacement peaks higher than far-field ones. Therefore, the importance of considering near-field ground motion effects in the seismic design of structures is clear. This study analyzes the seismic response of five-story steel moment-resisting frames subjected to Loma Prieta (1989 earthquake—Gilroy (far-field register and Santa Cruz (near-field register. The design of the frames verifies all the resistance and stability Eurocodes’ requirements and the first mode has been determined from previous shaking-table tests. In the frames two diagonal braces are installed in different positions. Therefore, ten cases with different periods are considered. Also, friction dampers are installed in substitution of the braces. The behaviour of the braced models under the far-field and the near-field records is analysed. The responses of the aforementioned frames equipped with friction dampers and subjected to the same ground motions are discussed. The maximum response of the examined model structures with and without passive dampers is analysed in terms of damage indices, acceleration amplification, base shear, and interstory drifts.

  14. The stratigraphic imprint of a mid-Telychian (Llandovery, Early Silurian glaciation on far-field shallow-water carbonates, Anticosti Island, Eastern Canada

    Directory of Open Access Journals (Sweden)

    François Clayer

    2014-12-01

    Full Text Available The near-field stratigraphic record of the Early Silurian glaciations is well documented in the literature. Data from far-field areas are, however, sparse. One of the best far-field stratigraphic records of these Llandovery glaciations is exposed on Anticosti Island in eastern Canada. Eight shallow-water paleotropical facies are present close to the mid-Telychian Jupiter–Chicotte formational boundary along the south-central coast of Anticosti Island. These can be grouped into three facies associations that include, from bottom to top: a carbonate facies association (FA-1, a mixed siliciclastic and carbonate facies association (FA-2 and an encrinitic facies association (FA-3. These mid- to outer-ramp strata represent deposition mostly from episodic, high-energy storm events as evidenced by their sharp bases, hummocky cross-stratification, large wave ripples, gutter casts and wave-enhanced sediment gravity flow deposits. Superimposed on a long-term regressive trend, one main transgressive–regressive (TR sequence and four meter-scale TR cycles are evident, indicating a multi-order stratigraphic framework developed under the influence of glacio-eustasy. The Jupiter–Chicotte formational boundary, a regional discontinuity surface caused by a forced regression, corresponds to the onset of a far-field mid-Telychian glaciation.

  15. Induced dual EIT and EIA resonances with optical trapping phenomenon in near/far fields in the N-type four-level system

    Science.gov (United States)

    Osman, Kariman I.; Joshi, Amitabh

    2017-01-01

    The optical trapping phenomenon is investigated in the probe absorptive susceptibility spectra, during the interaction of four-level N-type atomic system with three transverse Gaussian fields, in a Doppler broadened medium. The system was studied under different temperature settings of 87Rb atomic vapor as well as different non-radiative decay rate. The system exhibits a combination of dual electromagnetically induced transparency with electromagnetically induced absorption (EIA) or transparency (EIT) resonances simultaneously in near/far field. Also, the optical trapping phenomenon is considerably affected by the non-radiative decay rate.

  16. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 2

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report, a bibliography, has been prepared, presenting work carried out world-wide since 1970 on the sorption of radionuclides under near- and far-field conditions. Work has been included where the results are relevant to the disposal of low- and intermediate-level radioactive waste in a cementitious repository in the UK. The bibliography has been prepared using the INIS database and includes eight hundred references, listed both by subject and by country. In addition to these indexes, full abstracts are presented in reverse chronological order. A brief description of the relevance and measurement of sorption parameters is included. (author)

  17. Pareto optimality between width of central lobe and peak sidelobe intensity in the far-field pattern of lossless phase-only filters for enhancement of transverse resolution.

    Science.gov (United States)

    Mukhopadhyay, Somparna; Hazra, Lakshminarayan

    2015-11-01

    Resolution capability of an optical imaging system can be enhanced by reducing the width of the central lobe of the point spread function. Attempts to achieve the same by pupil plane filtering give rise to a concomitant increase in sidelobe intensity. The mutual exclusivity between these two objectives may be considered as a multiobjective optimization problem that does not have a unique solution; rather, a class of trade-off solutions called Pareto optimal solutions may be generated. Pareto fronts in the synthesis of lossless phase-only pupil plane filters to achieve superresolution with prespecified lower limits for the Strehl ratio are explored by using the particle swarm optimization technique.

  18. Far field photoluminescence imaging of single AlGaN nanowire in the sub-wavelength scale using confinement of polarized light

    Energy Technology Data Exchange (ETDEWEB)

    Sivadasan, A.K.; Dhara, Sandip [Nanomaterials and Sensors Section, Surface and Nanoscience Division, Indira Gandhi Centre for Atomic Research, Homi Bhabha National Institute, Kalpakkam (India); Sardar, Manas [Theoretical Studies Section, Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2017-03-15

    Till now the nanoscale focusing and imaging in the sub-diffraction limit is achieved mainly with the help of plasmonic field enhancement by confining the light assisted with noble metal nanostructures. Using far field imaging technique, we have recorded polarized spectroscopic photoluminescence (PL) imaging of a single AlGaN nanowire (NW) of diameter ∝100 nm using confinement of polarized light. It is found that the PL from a single NW is influenced by the proximity to other NWs. The PL intensity is proportional to 1/(l x d), where l and d are the average NW length and separation between the NWs, respectively. We suggest that the proximity induced PL intensity enhancement can be understood by assuming the existence of reasonably long lived photons in the intervening space between the NWs. A nonzero non-equilibrium population of such photons may cause stimulated emission leading to the enhancement of PL emission with the intensity proportional to 1/(l x d). The enhancement of PL emission facilitates far field spectroscopic imaging of a single semiconductor AlGaN NW of sub-wavelength dimension. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Efficient DoA Tracking of Variable Number of Moving Stochastic EM Sources in Far-Field Using PNN-MLP Model

    Directory of Open Access Journals (Sweden)

    Zoran Stanković

    2015-01-01

    Full Text Available An efficient neural network-based approach for tracking of variable number of moving electromagnetic (EM sources in far-field is proposed in the paper. Electromagnetic sources considered here are of stochastic radiation nature, mutually uncorrelated, and at arbitrary angular distance. The neural network model is based on combination of probabilistic neural network (PNN and the Multilayer Perceptron (MLP networks and it performs real-time calculations in two stages, determining at first the number of moving sources present in an observed space sector in specific moments in time and then calculating their angular positions in azimuth plane. Once successfully trained, the neural network model is capable of performing an accurate and efficient direction of arrival (DoA estimation within the training boundaries which is illustrated on the appropriate example.

  20. Far-field dynamic behavior of a half-space under an inertial strip foundation subjected to a time-harmonic force

    Directory of Open Access Journals (Sweden)

    M. Dehestani

    Full Text Available Recent research works demonstrated that the interaction between the loads and the carrying structure's boundary which is related to the inertia of the load is an influential factor on the dynamic response of the structure. Although effects of the inertia in moving loads were considered in many works, very few papers can be found on the inertial effects of the stationary loads on structures. In this paper, an elastodynamic formulation was employed to investigate the dynamic response of a homogeneous isotropic elastic half-space under an inertial strip foundation subjected to a time-harmonic force. Fourier integral transformation was used to solve the system of Poisson-type partial differential equation considering the boundary conditions and the inertial effects. Steepest descent method was employed to obtain the approximate far-field displacements and stresses. A numerical example is presented to illustrate the methodology and typical results.

  1. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 1

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report presents and discusses work funded by the Department of the Environment and UK Nirex Ltd in the area of sorption of radionuclides under near-field and far-field conditions as related to the underground disposal of radioactive waste in the UK. It is intended as a basis for comparison with work undertaken world-wide in the sorption area, presented in Part II of this review. The UK and overseas work are compared in Part III. From lists of reports and papers supplied by DOE (HMIP) and Nirex, those publications believed to be relevant were selected and are listed here by subject. Summaries of all these reports are included in the form of abstracts, or where available, executive summaries. The work presented is further summarised and discussed. Sections on sorption and laboratory experimental methods are included, along with a section on the level of understanding and outstanding issues. (Author)

  2. Consistency of the directionality of partially coherent beams in turbulence expressed in terms of the angular spread and the far-field average intensity

    International Nuclear Information System (INIS)

    Xiao-Wen, Chen; Xiao-Ling, Ji

    2010-01-01

    Under the quadratic approximation of the Rytov's phase structure function, this paper derives the general closed-form expressions for the mean-squared width and the angular spread of partially coherent beams in turbulence. It finds that under a certain condition different types of partially coherent beams may have the same directionality as a fully coherent Gaussian beam in free space and also in atmospheric turbulence if the angular spread is chosen as the characteristic parameter of beam directionality. On the other hand, it shows that generally, the directionality of partially coherent beams expressed in terms of the angular spread is not consistent with that in terms of the normalized far-field average intensity distribution in free space, but the consistency can be achieved due to turbulence. (classical areas of phenomenology)

  3. Assessment of the Bordas-Carnot Losses within the diffuser of tidal turbines using far-field and near-field CFD models.

    Science.gov (United States)

    Hajaali, Arthur

    2017-04-01

    This project has for ambition to analyse and further the general understanding on cross-flows interactions and behaviours at the mouth of a mini/small tidal hydropower plant and a river. Although, the study of these interactions could benefit and find applications in multiple hydraulic problems, this project concentrates its focus on the influence of the transposed turbulences generated by the cross-flow into the diffuser. These eddies affect the overall performance and efficiency of the bulb-turbines by minimizing the pressure recovery. In the past, these turbulences were accounted with the implementation of the Bordas-Carnot losses coefficient for the design of tidal project using bulb-turbines. The bulb turbine technology has been the interest and subject of many scientific papers but most of them concentrate and narrow their focus on the design of the rotor, blades and combiner. This project wants to focus the design of the diffuser by performing an analysis on the development of eddies and the turbulences using computational fluid dynamic (CFD) models. The Severn estuary is endowed with one of the highest tidal range around the hemisphere. The first part of the research requires to select case studies sites such as Briton-Ferry to virtually design mini-tidal plant in 0-Dimentional (D), 2D and 3D modelling to study development and behaviour of turbulences within the diffuser. The far-field model represents the marine environment prior and after the structure where bulb turbines are located. The near-field modelling has allowed researcher to study at much higher resolution and precision the design of a single turbine feeding model with predetermined and fix boundary condition. For this reason, a near-field model is required to study in depth the behaviour and evolution of the turbulence with the diffuser. One of the main challenge and advancement of this research is to find a methodology and system to link the far-field and near-field modelling to produce an

  4. Effects of near surface soil moisture profiles during evaporation on far-field ground-penetrating radar data: A numerical study

    KAUST Repository

    Moghadas, Davood

    2013-01-01

    We theoretically investigated the effect of vapor flow on the drying front that develops in soils when water evaporates from the soil surface and on GPR data. The results suggest the integration of the full-wave GPR model with a coupled water, vapor, and heat flow model to accurately estimate the soil hydraulic properties. We investigated the Effects of a drying front that emerges below an evaporating soil surface on the far-field ground-penetrating radar (GPR) data. First, we performed an analysis of the width of the drying front in soils with 12 different textures by using an analytical model. Then, we numerically simulated vertical soil moisture profiles that develop during evaporation for the soil textures. We performed the simulations using a Richards flow model that considers only liquid water flow and a model that considers coupled water, vapor, and heat flows. The GPR signals were then generated from the simulated soil water content profiles taking into account the frequency dependency of apparent electrical conductivity and dielectric permittivity. The analytical approach indicated that the width of the drying front at the end of Stage I of the evaporation was larger in silty soils than in other soil textures and smaller in sandy soils. We also demonstrated that the analytical estimate of the width of the drying front can be considered as a proxy for the impact that a drying front could have on far-field GPR data. The numerical simulations led to the conclusion that vapor transport in soil resulted in S-shaped soil moisture profiles, which clearly influenced the GPR data. As a result, vapor flow needs to be considered when GPR data are interpreted in a coupled inversion approach. Moreover, the impact of vapor flow on the GPR data was larger for silty than for sandy soils. These Effects on the GPR data provide promising perspectives regarding the use of radars for evaporation monitoring. © Soil Science Society of America 5585 Guilford Rd., Madison, WI

  5. Far-field tsunami of 2017 Mw 8.1 Tehuantepec, Mexico earthquake recorded by Chilean tide gauge network: Implications for tsunami warning systems

    Science.gov (United States)

    González-Carrasco, J. F.; Benavente, R. F.; Zelaya, C.; Núñez, C.; Gonzalez, G.

    2017-12-01

    The 2017 Mw 8.1, Tehuantepec earthquake generated a moderated tsunami, which was registered in near-field tide gauges network activating a tsunami threat state for Mexico issued by PTWC. In the case of Chile, the forecast of tsunami waves indicate amplitudes less than 0.3 meters above the tide level, advising an informative state of threat, without activation of evacuation procedures. Nevertheless, during sea level monitoring of network we detect wave amplitudes (> 0.3 m) indicating a possible change of threat state. Finally, NTWS maintains informative level of threat based on mathematical filtering analysis of sea level records. After 2010 Mw 8.8, Maule earthquake, the Chilean National Tsunami Warning System (NTWS) has increased its observational capabilities to improve early response. Most important operational efforts have focused on strengthening tide gauge network for national area of responsibility. Furthermore, technological initiatives as Integrated Tsunami Prediction and Warning System (SIPAT) has segmented the area of responsibility in blocks to focus early warning and evacuation procedures on most affected coastal areas, while maintaining an informative state for distant areas of near-field earthquake. In the case of far-field events, NTWS follow the recommendations proposed by Pacific Tsunami Warning Center (PTWC), including a comprehensive monitoring of sea level records, such as tide gauges and DART (Deep-Ocean Assessment and Reporting of Tsunami) buoys, to evaluate the state of tsunami threat in the area of responsibility. The main objective of this work is to analyze the first-order physical processes involved in the far-field propagation and coastal impact of tsunami, including implications for decision-making of NTWS. To explore our main question, we construct a finite-fault model of the 2017, Mw 8.1 Tehuantepec earthquake. We employ the rupture model to simulate a transoceanic tsunami modeled by Neowave2D. We generate synthetic time series at

  6. Combined near- and far-field high-energy diffraction microscopy dataset for Ti-7Al tensile specimen elastically loaded in situ

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Todd J.; Shade, Paul A.; Bernier, Joel V.; Li, Shiu Fai; Schuren, Jay C.; Lind, Jonathan; Lienert, Ulrich; Kenesei, Peter; Suter, Robert M.; Blank, Basil; Almer, Jonathan

    2016-03-18

    High-energy diffraction microscopy (HEDM) constitutes a suite of combined X-ray characterization methods, which hold the unique advantage of illuminating the microstructure and micromechanical state of a material during concurrent in situ mechanical deformation. The data generated from HEDM experiments provides a heretofore unrealized opportunity to validate meso-scale modeling techniques, such as crystal plasticity finite element modeling (CPFEM), by explicitly testing the accuracy of these models at the length scales where the models predict their response. Combining HEDM methods with in situ loading under known and controlled boundary conditions represents a significant challenge, inspiring the recent development of a new high-precision rotation and axial motion system for simultaneously rotating and axially loading a sample. In this paper, we describe the initial HEDM dataset collected using this hardware on an alpha-titanium alloy (Ti-7Al) under in situ tensile deformation at the Advanced Photon Source, Argonne National Laboratory. We present both near-field HEDM data that maps out the grain morphology and intragranular crystallographic orientations and far-field HEDM data that provides the grain centroid, grain average crystallographic orientation, and grain average elastic strain tensor for each grain. Finally, we provide a finite element mesh that can be utilized to simulate deformation in the volume of this Ti-7Al specimen. The dataset supporting this article is available in the National Institute of Standards and Technology (NIST) repository (http://hdl.handle.net/11256/599).

  7. FDTD analysis of temperature elevation in the lens of human and rabbit models due to near-field and far-field exposures at 2.45 GHz

    International Nuclear Information System (INIS)

    Oizumi, T.; Laakso, I.; Hirata, A.; Fujiwara, O.; Watanabe, S.; Taki, M.; Kojima, M.; Sasaki, H.; Sasaki, K.

    2013-01-01

    The eye is said to be one of the most sensitive organs to microwave heating. According to previous studies, the possibility of microwave-induced cataract formation has been experimentally investigated in rabbit and monkey eyes, but not for the human eye due to ethical reasons. In the present study, the temperature elevation in the lens, the skin around the eye and the core temperature of numerical human and rabbit models for far-field and near-field exposures at 2.45 GHz are investigated. The temperature elevations in the human and rabbit models were compared with the threshold temperatures for inducing cataracts, thermal pain in the skin and reversible health effects such as heat exhaustion or heat stroke. For plane-wave exposure, the core temperature elevation is shown to be essential both in the human and in the rabbit models as suggested in the international guidelines and standards. For localised exposure of the human eye, the temperature elevation of the skin was essential, and the lens temperature did not reach its threshold for thermal pain. On the other hand, the lens temperature elevation was found to be dominant for the rabbit eye. (authors)

  8. FDTD analysis of temperature elevation in the lens of human and rabbit models due to near-field and far-field exposures at 2.45 GHz.

    Science.gov (United States)

    Oizumi, Takuya; Laakso, Ilkka; Hirata, Akimasa; Fujiwara, Osamu; Watanabe, Soichi; Taki, Masao; Kojima, Masami; Sasaki, Hiroshi; Sasaki, Kazuyuki

    2013-07-01

    The eye is said to be one of the most sensitive organs to microwave heating. According to previous studies, the possibility of microwave-induced cataract formation has been experimentally investigated in rabbit and monkey eyes, but not for the human eye due to ethical reasons. In the present study, the temperature elevation in the lens, the skin around the eye and the core temperature of numerical human and rabbit models for far-field and near-field exposures at 2.45 GHz are investigated. The temperature elevations in the human and rabbit models were compared with the threshold temperatures for inducing cataracts, thermal pain in the skin and reversible health effects such as heat exhaustion or heat stroke. For plane-wave exposure, the core temperature elevation is shown to be essential both in the human and in the rabbit models as suggested in the international guidelines and standards. For localised exposure of the human eye, the temperature elevation of the skin was essential, and the lens temperature did not reach its threshold for thermal pain. On the other hand, the lens temperature elevation was found to be dominant for the rabbit eye.

  9. Numerical modeling of radionuclide migration in water-saturated planar fracture: study of performance of bentonite in the far-field region

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Claudia S. da; Alvim, Antonio C.M., E-mail: csilveira@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Energia Nuclear

    2011-07-01

    The analysis of radionuclide migration in fractured porous media is an important part of the safety assessment of a deep geologic disposal for high level radioactive wastes. In this work, numerical solution for simple geometry was developed to study radionuclide migration, including decay chain from a hypothetical repository, whereas the initial region of fracture is filled with bentonite which expanded from EBS (Engineered Barrier System). The following cases were considered: convective transport with constant velocity along the fracture, longitudinal hydrodynamic dispersion in the fracture along the fracture axis, molecular diffusion from fracture into rock matrix, sorption within rock matrix, sorption onto the surface of the fracture, radioactive decay, decay chain, and diffusion in bentonite extrusion region. For conservative analysis, the porous matrix adjacent to the fracture was subdivided into two different subdomains, each with different set of parameters and considering that the radionuclides were available for migration in the solubility limit, at fracture inlet, from the initial time. The partial differential equations that govern the physical system were discretized by finite differences, by using the Implicit Euler Method with forward scheme in the convective term. In this study, numerical simulation was performed for 100, 1000 and 10000 years, with and without bentonite extrusion, in order to compare the migration retardation obtained by bentonite located at the beginning of the fracture in saturated environment. The numerical simulation results showed the importance of extruded area in the far field region of the fractured host rock. (author)

  10. Numerical modeling of radionuclide migration in water-saturated planar fracture: study of performance of bentonite in the far-field region

    International Nuclear Information System (INIS)

    Silveira, Claudia S. da; Alvim, Antonio C.M.

    2011-01-01

    The analysis of radionuclide migration in fractured porous media is an important part of the safety assessment of a deep geologic disposal for high level radioactive wastes. In this work, numerical solution for simple geometry was developed to study radionuclide migration, including decay chain from a hypothetical repository, whereas the initial region of fracture is filled with bentonite which expanded from EBS (Engineered Barrier System). The following cases were considered: convective transport with constant velocity along the fracture, longitudinal hydrodynamic dispersion in the fracture along the fracture axis, molecular diffusion from fracture into rock matrix, sorption within rock matrix, sorption onto the surface of the fracture, radioactive decay, decay chain, and diffusion in bentonite extrusion region. For conservative analysis, the porous matrix adjacent to the fracture was subdivided into two different subdomains, each with different set of parameters and considering that the radionuclides were available for migration in the solubility limit, at fracture inlet, from the initial time. The partial differential equations that govern the physical system were discretized by finite differences, by using the Implicit Euler Method with forward scheme in the convective term. In this study, numerical simulation was performed for 100, 1000 and 10000 years, with and without bentonite extrusion, in order to compare the migration retardation obtained by bentonite located at the beginning of the fracture in saturated environment. The numerical simulation results showed the importance of extruded area in the far field region of the fractured host rock. (author)

  11. Dynamical heat transport amplification in a far-field thermal transistor of VO{sub 2} excited with a laser of modulated intensity

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez-Miranda, Jose, E-mail: jose.ordonez@cnrs.pprime.fr; Ezzahri, Younès; Drevillon, Jérémie; Joulain, Karl [Institut Pprime, CNRS, Université de Poitiers, ISAE-ENSMA, F-86962 Futuroscope Chasseneuil (France)

    2016-05-28

    Far-field radiative heat transport in a thermal transistor made up of a vanadium dioxide base excited with a laser of modulated intensity is analytically studied and optimized. This is done by solving the equation of energy conservation for the steady-state and modulated components of the temperature and heat fluxes that the base exchanges with the collector and emitter. The thermal bistability of VO{sub 2} is used to find an explicit condition on the laser intensity required to maximize these heat fluxes to values higher than the incident flux. For a 1 μm-thick base heated with a modulation frequency of 0.5 Hz, it is shown that both the DC and AC components of the heat fluxes are about 4 times the laser intensity, while the AC temperature remains an order of magnitude smaller than the DC one at around 343 K. Higher AC heat fluxes are obtained for thinner bases and/or lower frequencies. Furthermore, we find that out of the bistability temperatures associated with the dielectric-to-metal and metal-to-dielectric transitions of VO{sub 2}, the amplification of the collector-to-base and base-to-emitter heat fluxes is still possible, but at modulation frequencies lower than 0.1 Hz.

  12. Numerical modeling to assess possible influence of the mine openings on far-field in-situ stress measurements at Stripa

    International Nuclear Information System (INIS)

    Chan, T.; Guvanasen, V.; Littlestone, N.

    1981-03-01

    Finite element analyses were carried out to assess the possible effects of the Stripa mine openings on the in-situ stress measured in a 400-m-deep borehole drilled from the surface. For this assessment, four 2-dimensional cases were modeled. These cases variously included two horizontal sections, and two separate, idealized vertical sections. An iron ore body in the mine was assumed to be completely extracted, thereby providing conservative estimates of stress concentration effects. Since no in-situ stress measurements were made before mining, overburden weight and horizontal stresses measured by hyrodfracturing were assumed to be the pre-mining state of stress. The stress state resulting from excavation of the mine was calculated by the finite element model. In the cases using horizontal sections, the model predicted a stress concentration factor at the borehole of approximately 1.15, which is negligible considering the difficulty of obtaining accurate stress measurements. For the vertical sections the model predicted higher stress concentration factors at depths less than 200 m. This was expected because the vertical sections chosen brought the borehole unrealistically close to the mine openings, thereby leading to overly conservative estimates. In general, deviations in the magnitudes and orientations of the calculated redistributed principal stresses from the assumed pre-mining state of stress were found to be comparable to the scatter of overcoring data. It is, therefore, recommended that, for near-field stress calculations, the vertical stress due to overburden weight and the horizontal stresses measured by hydrofracturing at the borehole be considered the unperturbed far-field in situ state of stress

  13. Far-field sorption data bases for performance assessment of a L/ILW repository in an undisturbed Palfris marl host rock

    International Nuclear Information System (INIS)

    Bradbury, M.H.; Baeyens, B.

    1997-12-01

    A Palfris marl formation at Wellenberg (Gemeinde Wolfenschiessen, NW) has been chosen by NAGRA as a potential repository site for low- and intermediate-level radioactive waste, L/ILW. In the coming years a series of performance assessment studies will be performed for this site. One set of key data required for such safety analysis calculations is sorption data bases (SDB) for safety relevant radionuclides in the far-field. The purpose of this report is to describe the procedures used to generate sorption data bases appropriate for the in situ conditions existing along the different potential flow paths in an undisturbed marl host rock formation. An important aim was to document the sources of sorption data used and, in particular, the processes by which data selections were mad.e. The main guiding principles here were 'transparency' and 'traceability'. Inherent within this whole process is also the justification for, and defensibility of, the selected values. Much of the sorption data used to generate the SDB for marl came from the open literature. A major part of this report is concerned with describing the procedures whereby these initial literature values are modified so that they apply to the actual marl mineralogies and groundwater chemistries. The resulting 'reference R d values' are then further modified using so called Lab -> Field transfer factors to produce sorption values which are appropriate to the in situ bulk rock conditions. The Lab -> Field transfer factors attempt to correct for the differences in sorption site availability between the crushed rock state used in batch tests and the intact rock state existing in reality in the host rock. There are two main groundwater chemistries and five characteristic mineralogical compositions which cover the three broad types of flow paths which have been identified in the Palfris marl formation. In principle the methodology described here to construct sorption data bases for marl is applicable to any type of

  14. Far-field sorption data bases for performance assessment of a L/ILW repository in an undisturbed Palfris marl host rock

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, M.H.; Baeyens, B. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-12-01

    A Palfris marl formation at Wellenberg (Gemeinde Wolfenschiessen, NW) has been chosen by NAGRA as a potential repository site for low- and intermediate-level radioactive waste, L/ILW. In the coming years a series of performance assessment studies will be performed for this site. One set of key data required for such safety analysis calculations is sorption data bases (SDB) for safety relevant radionuclides in the far-field. The purpose of this report is to describe the procedures used to generate sorption data bases appropriate for the in situ conditions existing along the different potential flow paths in an undisturbed marl host rock formation. An important aim was to document the sources of sorption data used and, in particular, the processes by which data selections were mad.e. The main guiding principles here were `transparency` and `traceability`. Inherent within this whole process is also the justification for, and defensibility of, the selected values. Much of the sorption data used to generate the SDB for marl came from the open literature. A major part of this report is concerned with describing the procedures whereby these initial literature values are modified so that they apply to the actual marl mineralogies and groundwater chemistries. The resulting `reference R{sub d} values` are then further modified using so called Lab -> Field transfer factors to produce sorption values which are appropriate to the in situ bulk rock conditions. The Lab -> Field transfer factors attempt to correct for the differences in sorption site availability between the crushed rock state used in batch tests and the intact rock state existing in reality in the host rock. There are two main groundwater chemistries and five characteristic mineralogical compositions which cover the three broad types of flow paths which have been identified in the Palfris marl formation. In principle the methodology described here to construct sorption data bases for marl is applicable to any

  15. FDTD analysis of human body-core temperature elevation due to RF far-field energy prescribed in the ICNIRP guidelines

    International Nuclear Information System (INIS)

    Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu

    2007-01-01

    This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the electromagnetic absorption and temperature elevation in NORMAN. In order to consider the variability of human thermoregulation, parameters for sweating are derived and incorporated into a conventional sweating formula. First, we investigated the effect of blood temperature variation modeling on body-core temperature. The computational results show that the modeling of blood temperature variation was the dominant factor influencing the body-core temperature. This is because the temperature in the inner tissues is elevated via the circulation of blood whose temperature was elevated due to EM absorption. Even at different frequencies, the body-core temperature elevation at an identical whole-body average specific absorption rate (SAR) was almost the same, suggesting the effectiveness of the whole-body average SAR as a measure in the ICNIRP guidelines. Next, we discussed the effect of sweating on the temperature elevation and thermal time constant of blood. The variability of temperature elevation caused by the sweating rate was found to be 30%. The blood temperature elevation at the basic restriction in the ICNIRP guidelines of 0.4 W kg -1 is 0.25 0 C even for a low sweating rate. The thermal time constant of blood temperature elevation was 23 min and 52 min for a man with a lower and a higher sweating rate, respectively, which is longer than the average time of the SAR in the ICNIRP guidelines. Thus, the whole-body average SAR required for blood temperature elevation of 1 0 C was 4.5 W kg -1 in the model of a human with the lower sweating coefficients for 60 min exposure. From a comparison of this value with the basic restriction in the ICNIRP guidelines of

  16. FDTD analysis of human body-core temperature elevation due to RF far-field energy prescribed in the ICNIRP guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu [Department of Computer Science and Engineering, Nagoya Institute of Technology (Japan)

    2007-08-21

    This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the electromagnetic absorption and temperature elevation in NORMAN. In order to consider the variability of human thermoregulation, parameters for sweating are derived and incorporated into a conventional sweating formula. First, we investigated the effect of blood temperature variation modeling on body-core temperature. The computational results show that the modeling of blood temperature variation was the dominant factor influencing the body-core temperature. This is because the temperature in the inner tissues is elevated via the circulation of blood whose temperature was elevated due to EM absorption. Even at different frequencies, the body-core temperature elevation at an identical whole-body average specific absorption rate (SAR) was almost the same, suggesting the effectiveness of the whole-body average SAR as a measure in the ICNIRP guidelines. Next, we discussed the effect of sweating on the temperature elevation and thermal time constant of blood. The variability of temperature elevation caused by the sweating rate was found to be 30%. The blood temperature elevation at the basic restriction in the ICNIRP guidelines of 0.4 W kg{sup -1} is 0.25 {sup 0}C even for a low sweating rate. The thermal time constant of blood temperature elevation was 23 min and 52 min for a man with a lower and a higher sweating rate, respectively, which is longer than the average time of the SAR in the ICNIRP guidelines. Thus, the whole-body average SAR required for blood temperature elevation of 1 {sup 0}C was 4.5 W kg{sup -1} in the model of a human with the lower sweating coefficients for 60 min exposure. From a comparison of this value with the basic restriction in the

  17. FDTD analysis of human body-core temperature elevation due to RF far-field energy prescribed in the ICNIRP guidelines.

    Science.gov (United States)

    Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu

    2007-08-21

    This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the electromagnetic absorption and temperature elevation in NORMAN. In order to consider the variability of human thermoregulation, parameters for sweating are derived and incorporated into a conventional sweating formula. First, we investigated the effect of blood temperature variation modeling on body-core temperature. The computational results show that the modeling of blood temperature variation was the dominant factor influencing the body-core temperature. This is because the temperature in the inner tissues is elevated via the circulation of blood whose temperature was elevated due to EM absorption. Even at different frequencies, the body-core temperature elevation at an identical whole-body average specific absorption rate (SAR) was almost the same, suggesting the effectiveness of the whole-body average SAR as a measure in the ICNIRP guidelines. Next, we discussed the effect of sweating on the temperature elevation and thermal time constant of blood. The variability of temperature elevation caused by the sweating rate was found to be 30%. The blood temperature elevation at the basic restriction in the ICNIRP guidelines of 0.4 W kg(-1) is 0.25 degrees C even for a low sweating rate. The thermal time constant of blood temperature elevation was 23 min and 52 min for a man with a lower and a higher sweating rate, respectively, which is longer than the average time of the SAR in the ICNIRP guidelines. Thus, the whole-body average SAR required for blood temperature elevation of 1 degrees C was 4.5 W kg(-1) in the model of a human with the lower sweating coefficients for 60 min exposure. From a comparison of this value with the basic restriction in the ICNIRP

  18. Three-dimensional modelling for assessment of far-field impact of tidal stream turbine: A case study at the Anglesey Coast, Wales, UK

    Science.gov (United States)

    Li, Xiaorong; Li, Ming; Wolf, Judith

    2017-04-01

    As a response to worldwide climate change, clean non-carbon renewable energy resources have been gaining significant attention. Among a range of renewable alternatives, tidal stream energy is considered very promising; due to its consistent predictability and availability. To investigate impacts of tidal stream devices on their surroundings, prototype experiments involving small scale laboratory studies have been implemented. Computational Flow Dynamics (CFD) modelling is also commonly applied to study turbine behaviours. However, these studies focus on impacts of the turbine in the near-field scale. As a result, in order to study and predict the far-field impacts caused by the operation of turbines, large scale 2D and 3D numerical oceanography models have been used, with routines added to reflect the impacts of turbines. In comparison to 2D models, 3D models are advantageous in providing complete prediction of vertical flow structures and hence mixing in the wake of a turbine. This research aims to deliver a thorough 3D tidal stream turbine simulation system, by considering major coastal processes, i.e. current, waves and sediment transport, based on a 3D wave-current-sediment fully coupled numerical oceanography model — the Unstructured Grid Finite Volume Community Ocean Model (FVCOM). The energy extraction of turbines is simulated by adding a body force to the momentum equations. Across the water depth, the coefficient related to the additional body force is given different values according to the turbine configuration and operation to reflect the vertical variation of the turbine's impacts on the passing flow. Three turbulence perturbation terms are added to the turbulence closure to simulate the turbine-induced turbulence generation, dissipation and interference for the turbulence length-scale. Impacts of turbine operation on surface waves are also considered by modification of wave energy flux across the device. A thorough validation study is carried out in

  19. Far field tsunami simulations of the 1755 Lisbon earthquake: Implications for tsunami hazard to the U.S. East Coast and the Caribbean

    Science.gov (United States)

    Barkan, R.; ten Brink, Uri S.; Lin, J.

    2009-01-01

    The great Lisbon earthquake of November 1st, 1755 with an estimated moment magnitude of 8.5-9.0 was the most destructive earthquake in European history. The associated tsunami run-up was reported to have reached 5-15??m along the Portuguese and Moroccan coasts and the run-up was significant at the Azores and Madeira Island. Run-up reports from a trans-oceanic tsunami were documented in the Caribbean, Brazil and Newfoundland (Canada). No reports were documented along the U.S. East Coast. Many attempts have been made to characterize the 1755 Lisbon earthquake source using geophysical surveys and modeling the near-field earthquake intensity and tsunami effects. Studying far field effects, as presented in this paper, is advantageous in establishing constraints on source location and strike orientation because trans-oceanic tsunamis are less influenced by near source bathymetry and are unaffected by triggered submarine landslides at the source. Source location, fault orientation and bathymetry are the main elements governing transatlantic tsunami propagation to sites along the U.S. East Coast, much more than distance from the source and continental shelf width. Results of our far and near-field tsunami simulations based on relative amplitude comparison limit the earthquake source area to a region located south of the Gorringe Bank in the center of the Horseshoe Plain. This is in contrast with previously suggested sources such as Marqu??s de Pombal Fault, and Gulf of C??diz Fault, which are farther east of the Horseshoe Plain. The earthquake was likely to be a thrust event on a fault striking ~ 345?? and dipping to the ENE as opposed to the suggested earthquake source of the Gorringe Bank Fault, which trends NE-SW. Gorringe Bank, the Madeira-Tore Rise (MTR), and the Azores appear to have acted as topographic scatterers for tsunami energy, shielding most of the U.S. East Coast from the 1755 Lisbon tsunami. Additional simulations to assess tsunami hazard to the U.S. East

  20. The use of interaction matrices for identification, structuring and ranking of FEPs in a repository system. Application on the far-field of a deep geological repository for spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, K; Wiborgh, M [Kemakta, Stockholm (Sweden); Stroem, A [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    1995-11-01

    The basic device in the Rock Engineering Systems approach, the interaction matrix, has been used to identify, structure and rank Features, Events, and Processes (FEPs) describing barrier performance and radionuclide behaviour in the far-field of a deep geologic repository for spent fuel. The result is a first version of the Process System (PS), for the far-field of a deep repository, structured in an interaction matrix with supporting documentation. The documentation is compiled in databases, one containing matrix specific information and one containing general FEP descriptions. The study has shown that an interaction matrix is feasible to use both for the structuring of the PS and for visualisation of the PS. The developed documentation system increases the transparency of the system description and makes it possible to trace back the judgements made during the construction of the matrix. This will facilitate review work and future revisions as well as consistent treatment of different issues in the system. This study is a first step in the application of a systematic method to establish a structured description of the PS for a deep repository for spent fuel. The work could be seen as a part of the preparation for the forthcoming performance and safety analysis. The next step would be to develop the PS for the remaining parts of the repository system to the same level as has been done for the far-field system. Before the PS is evaluated for different selected system premises, a scientific review of the contents of the PS for the whole repository system would be beneficial. 5 refs.

  1. The use of interaction matrices for identification, structuring and ranking of FEPs in a repository system. Application on the far-field of a deep geological repository for spent fuel

    International Nuclear Information System (INIS)

    Skagius, K.; Wiborgh, M.; Stroem, A.

    1995-11-01

    The basic device in the Rock Engineering Systems approach, the interaction matrix, has been used to identify, structure and rank Features, Events, and Processes (FEPs) describing barrier performance and radionuclide behaviour in the far-field of a deep geologic repository for spent fuel. The result is a first version of the Process System (PS), for the far-field of a deep repository, structured in an interaction matrix with supporting documentation. The documentation is compiled in databases, one containing matrix specific information and one containing general FEP descriptions. The study has shown that an interaction matrix is feasible to use both for the structuring of the PS and for visualisation of the PS. The developed documentation system increases the transparency of the system description and makes it possible to trace back the judgements made during the construction of the matrix. This will facilitate review work and future revisions as well as consistent treatment of different issues in the system. This study is a first step in the application of a systematic method to establish a structured description of the PS for a deep repository for spent fuel. The work could be seen as a part of the preparation for the forthcoming performance and safety analysis. The next step would be to develop the PS for the remaining parts of the repository system to the same level as has been done for the far-field system. Before the PS is evaluated for different selected system premises, a scientific review of the contents of the PS for the whole repository system would be beneficial. 5 refs

  2. Far-field detection of sub-wavelength Tetris without extra near-field metal parts based on phase prints of time-reversed fields with intensive background interference.

    Science.gov (United States)

    Chen, Yingming; Wang, Bing-Zhong

    2014-07-14

    Time-reversal (TR) phase prints are first used in far-field (FF) detection of sub-wavelength (SW) deformable scatterers without any extra metal structure positioned in the vicinity of the target. The 2D prints derive from discrete short-time Fourier transform of 1D TR electromagnetic (EM) signals. Because the time-invariant intensive background interference is effectively centralized by TR technique, the time-variant weak indication from FF SW scatterers can be highlighted. This method shows a different use of TR technique in which the focus peak of TR EM waves is unusually removed and the most useful information is conveyed by the other part.

  3. Far-Field Acoustic Power Level and Performance Analyses of F31/A31 Open Rotor Model at Simulated Scaled Takeoff, Nominal Takeoff, and Approach Conditions: Technical Report I

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Far-field acoustic power level and performance analyses of open rotor model F31/A31 have been performed to determine its noise characteristics at simulated scaled takeoff, nominal takeoff, and approach flight conditions. The nonproprietary parts of the data obtained from experiments in 9- by 15-Foot Low-Speed Wind Tunnel (9?15 LSWT) tests were provided by NASA Glenn Research Center to perform the analyses. The tone and broadband noise components have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, angle of attack, thrust, and input shaft power have been presented and discussed. The effect of an upstream pylon on the noise levels of the model has been addressed. Empirical equations relating model's acoustic power level, thrust, and input shaft power have been developed. The far-field acoustic efficiency of the model is also determined for various simulated flight conditions. It is intended that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  4. Transient, two-dimensional, discrete-element, far-field model for thermal impact analysis of power plant discharges in coastal and offshore regions. Part I. General description of the mathematical model and the results of an application

    International Nuclear Information System (INIS)

    Eraslan, A.H.

    1975-02-01

    A far-field mathematical model is presented for numerical simulation of short-time (within tidal cycle) transient, two-dimensional temperature distributions in large coastal and offshore regions resulting from the condenser cooling water discharges of power plants. The Eulerian FLIDE (fluid-in-discrete-element) formulation employs the integral forms of the conservation principles for mass and thermal energy in variable-sized discrete elements that span the specific flow region. The contributions of vertical variations of the velocity components and temperature are rigorously incorporated in the development of depth-averaged, two-dimensional energy transport fluxes by spatially integrating the conservation equations over the enclosure surfaces of the discrete elements. The general mathematical formulation considers completely arbitrary, transient oceanic flow conditions, which include periodic tidal, geostrophic, and wind-induced currents, as locally specified inputs to the model. The thermal impact of a hypothetical, multiunit generating station in a coastal region is analyzed where the oceanic flow conditions are assumed to be strictly periodic tidal currents within any appreciable net drift of sufficient duration to remove the heated effluent. The numerical simulation indicates that the periodic flow conditions cause considerable variations in the temperature distributions during the day and the tidal cycles, which result in severe recirculation and re-entrainment of the heated water between the intakes and the discharges of the different units. This leads to a gradual, long-term increase of the temperatures in the immediate vicinity of the discharge structures and also in the far-field zone. (U.S.)

  5. Comparison of the near field/far field model and the advanced reach tool (ART) model V1.5: exposure estimates to benzene during parts washing with mineral spirits.

    Science.gov (United States)

    LeBlanc, Mallory; Allen, Joseph G; Herrick, Robert F; Stewart, James H

    2018-03-01

    The Advanced Reach Tool V1.5 (ART) is a mathematical model for occupational exposures conceptually based on, but implemented differently than, the "classic" Near Field/Far Field (NF/FF) exposure model. The NF/FF model conceptualizes two distinct exposure "zones"; the near field, within approximately 1m of the breathing zone, and the far field, consisting of the rest of the room in which the exposure occurs. ART has been reported to provide "realistic and reasonable worst case" estimates of the exposure distribution. In this study, benzene exposure during the use of a metal parts washer was modeled using ART V1.5, and compared to actual measured workers samples and to NF/FF model results from three previous studies. Next, the exposure concentrations expected to be exceeded 25%, 10% and 5% of the time for the exposure scenario were calculated using ART. Lastly, ART exposure estimates were compared with and without Bayesian adjustment. The modeled parts washing benzene exposure scenario included distinct tasks, e.g. spraying, brushing, rinsing and soaking/drying. Because ART can directly incorporate specific types of tasks that are part of the exposure scenario, the present analysis identified each task's determinants of exposure and performance time, thus extending the work of the previous three studies where the process of parts washing was modeled as one event. The ART 50th percentile exposure estimate for benzene (0.425ppm) more closely approximated the reported measured mean value of 0.50ppm than the NF/FF model estimates of 0.33ppm, 0.070ppm or 0.2ppm obtained from other modeling studies of this exposure scenario. The ART model with the Bayesian analysis provided the closest estimate to the measured value (0.50ppm). ART (with Bayesian adjustment) was then used to assess the 75th, the 90th and 95th percentile exposures, predicting that on randomly selected days during this parts washing exposure scenario, 25% of the benzene exposures would be above 0.70ppm; 10

  6. Patterning via optical saturable transitions

    Science.gov (United States)

    Cantu, Precious

    For the past 40 years, optical lithography has been the patterning workhorse for the semiconductor industry. However, as integrated circuits have become more and more complex, and as device geometries shrink, more innovative methods are required to meet these needs. In the far-field, the smallest feature that can be generated with light is limited to approximately half the wavelength. This, so called far-field diffraction limit or the Abbe limit (after Prof. Ernst Abbe who first recognized this), effectively prevents the use of long-wavelength photons >300nm from patterning nanostructures barrier is developed and experimentally verified. This approach, which I refer to as Patterning via Optical Saturable Transitions (POST) has the potential for massive parallelism, enabling the creation of nanostructures and devices at a speed far surpassing what is currently possible with conventional optical lithographic techniques. The fundamental understanding of this technique goes beyond optical lithography in the semiconductor industry and is applicable to any area that requires the rapid patterning of large-area two or three-dimensional complex geometries. At a basic level, this research intertwines the fields of electrochemistry, material science, electrical engineering, optics, physics, and mechanical engineering with the goal of developing a novel super-resolution lithographic technique.

  7. NEAR AND FAR-FIELD EFFECTS OF TSUNAMIS GENERATED BY THE PAROXYSMAL ERUPTIONS, EXPLOSIONS, CALDERA COLLAPSES AND MASSIVE SLOPE FAILURES OF THE KRAKATAU VOLCANO IN INDONESIA ON AUGUST 26-27, 1883

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2003-01-01

    source region. It took approximately 2.5 hours for the tsunami waves to refract around Java and reach Batavia (Jakarta where the only operating tide gauge existed. Wavesof 2.4 meters in height were recorded - but with an unusually long period of 122 minutes. The long period is attributed to modification due to resonance effects and did not reflect source characteristics. The tsunami travel time to Surabaya at the eastern part of Java was 11.9 hours. The reported wave was only 0.2 meters.The far field effects of the tsunami were noticeable around the world, but insignificant. Small sea level oscillations were recorded by tide gauges at Port Blair in the Andaman Sea, at Port Elizabeth in South Africa, and as far away as Australia, New Zealand, Japan, Hawaii, Alaska, the North-American West Coast, South America, and even as far away as the English Channel. It took 12 hours for the tsunami to reach Aden on the southern tip of the Arabian Peninsula, about 3800 nautical miles away. The wave reported at Aden, at Port Blair and at Port Elizabeth, represents the actual tsunami generated in the Sunda Strait. There were no land boundaries on the Indian Ocean side of Krakatau to prevent the tsunami energy from spreading in that direction. The tsunami travel time of a little over 300 nautical miles per hour to Aden appears reasonable. However, it is doubtful that the waves, which were reported at distant locations in the Pacific or in the Atlantic Ocean, represented the actual tsunami generated in the Sunda Strait. Very little, if any at all, of the tsunami energy could have escaped the surrounding inland seas to the east of the Sunda Strait. Most probably, the small waves that were observed in the Pacific as well as in the Atlantic were generated by the atmospheric pressure wave of the major Krakatoa explosion, and not from the actual tsunami generated in the Sunda Strait. The unusual flooding, which occurred at the Bay of Cardiff, in the U.K., was caused by atmospheric coupling of

  8. Static and wind tunnel near-field/far-field jet noise measurements from model scale single-flow base line and suppressor nozzles. Summary report. [conducted in the Boeing large anechoic test chamber and the NASA-Ames 40by 80-foot wind tunnel

    Science.gov (United States)

    Jaeck, C. L.

    1977-01-01

    A test program was conducted in the Boeing large anechoic test chamber and the NASA-Ames 40- by 80-foot wind tunnel to study the near- and far-field jet noise characteristics of six baseline and suppressor nozzles. Static and wind-on noise source locations were determined. A technique for extrapolating near field jet noise measurements into the far field was established. It was determined if flight effects measured in the near field are the same as those in the far field. The flight effects on the jet noise levels of the baseline and suppressor nozzles were determined. Test models included a 15.24-cm round convergent nozzle, an annular nozzle with and without ejector, a 20-lobe nozzle with and without ejector, and a 57-tube nozzle with lined ejector. The static free-field test in the anechoic chamber covered nozzle pressure ratios from 1.44 to 2.25 and jet velocities from 412 to 594 m/s at a total temperature of 844 K. The wind tunnel flight effects test repeated these nozzle test conditions with ambient velocities of 0 to 92 m/s.

  9. Far Field Modeling Methods For Characterizing Surface Detonations

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-08

    Savannah River National Laboratory (SRNL) analyzed particle samples collected during experiments that were designed to replicate tests of nuclear weapons components that involve detonation of high explosives (HE). SRNL collected the particle samples in the HE debris cloud using innovative rocket propelled samplers. SRNL used scanning electronic microscopy to determine the elemental constituents of the particles and their size distributions. Depleted uranium composed about 7% of the particle contents. SRNL used the particle size distributions and elemental composition to perform transport calculations that indicate in many terrains and atmospheric conditions the uranium bearing particles will be transported long distances downwind. This research established that HE tests specific to nuclear proliferation should be detectable at long downwind distances by sampling airborne particles created by the test detonations.

  10. A Far-Field Electro-Magnetic Tractor Beam

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this project was to demonstrate and model a cooperative, attractive, longrange force between a pair of satellites. NASA needs such a capability in order...

  11. Far field effects of complex noise barrier reflections

    NARCIS (Netherlands)

    Lutgendorf, D.; Wessels, P.W.; Eerden, F.J.M. van den; Roo, F. de

    2012-01-01

    Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

  12. Far-field RF energy transfer and harvesting

    NARCIS (Netherlands)

    Visser, H.J.; Vullers, R.; Briand, D.; Yeatman, E.; Roundy, S.

    2015-01-01

    This chapter deals with radio frequency (RF) energy transfer over a distance. After explaining the differences between nonradiative and radiative RF energy transfer, the chapter gives definitions for transfer and harvesting. Nonradiative RF energy transfer is mostly employed in inductive systems,

  13. Far field hydrogeochemistry in the Oklo reactor area (Gabon)

    International Nuclear Information System (INIS)

    Toulhoat, P.; Gallien, J.P.; L'Henoret, P.

    1993-01-01

    In the frame of a general study of the Oklo natural reactor, which takes into account the natural analogue aspect, a complete hydrogeological and hydrogeochemical study is undertaken. The partners of this study are the following: - Section de geochimie, CEA (France): P. Toulhoat, J.P. Gallien, P. L'Henoret, V. Moulin (groundwater chemistry and colloids). - Ecole des Mines de Paris (CIG, Fontainebleau) E. Ledoux, I. Gurban (hydrogeology and modelling) - SKB and Conterra AB (Sweden) J.A.T. Smellie, A. Winberg (hydrogeology, isotope geochemistry). The aim of this study is to try to understand and to characterize the possible mobilization of elements or isotopes when groundwaters come in contact with nuclear reaction zones. The first step of the study is presented here, which comprises a general geochemical and hydrodynamical characterization of the site. In this presentation, the site of Bagombe is also mentioned as it has been confirmed as sector in which nuclear fission reactions occurred as in Oklo. (author). 10 refs., 6 figs., 6 tabs

  14. IP FUNMIG: The European far-field project

    International Nuclear Information System (INIS)

    Kienzler, B.; Buckau, G.

    2007-01-01

    The fundamental processes of radionuclide migration (the FUNMIG) is the subject matter for the Integral Project in terms of the European Commission 6-th Frame Programme (the FP6). Within the frameworks of the Project one focuses on the processes of the hot radionuclide interaction with various rocks associated with the migration of the hot radionuclides from the deep underground storage. Paper describes the Project objectives, arrangement and implementation. One highlights the German involvement in the Project [ru

  15. Plasmonic Devices for Near and Far-Field Applications

    KAUST Repository

    Alrasheed, Salma

    2017-01-01

    In the first part of the thesis, we demonstrate the detection of single point mutation in peptides from multicomponent mixtures for early breast cancer detection using selfsimilar chain (SCC) plasmonic devices that show high field enhancement

  16. Far-field coseismic ionospheric disturbances of Tohoku earthquake

    Czech Academy of Sciences Publication Activity Database

    Krasnov, V. M.; Drobzheva, Ya. V.; Chum, Jaroslav

    2015-01-01

    Roč. 135, December (2015), s. 12-21 ISSN 1364-6826 R&D Projects: GA ČR(CZ) GC15-07281J Institutional support: RVO:68378289 Keywords : earthquake * infrasonic waves * ionospheric disturbances * infrasound triggered by the earthquake * co-seismic ionospheric perturbations * modeling * remote sensing Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.463, year: 2015 http://www.sciencedirect.com/science/article/pii/S1364682615300584

  17. Base Station Antenna Pattern Distortion in Practical Urban Deployment Scenarios

    DEFF Research Database (Denmark)

    Rodriguez Larrad, Ignacio; Nguyen, Huan Cong; Sørensen, Troels Bundgaard

    2014-01-01

    In real urban deployments, base station antennas are typically not placed in free space conditions. Therefore, the radiation pattern can be affected by mounting structures and nearby obstacles located in the proximity of the antenna (near-field), which are often not taken into consideration. Also...... presents a combination of near-field and far-field simulations aimed to provide an overview of the distortion experienced by the base station antenna pattern in two different urban deployment scenarios: rooftop and telecommunications tower. The study illustrates how, in comparison with the near...

  18. Generation of crystal-structure transverse patterns via a self-frequency-doubling laser.

    Science.gov (United States)

    Yu, Haohai; Zhang, Huaijin; Wang, Yicheng; Wang, Zhengping; Wang, Jiyang; Petrov, V

    2013-01-01

    Two-dimensional (2D) visible crystal-structure patterns analogous to the quantum harmonic oscillator (QHO) have been experimentally observed in the near- and far-fields of a self-frequency-doubling (SFD) microchip laser. Different with the fundamental modes, the localization of the SFD light is changed with the propagation. Calculation based on Hermite-Gaussian (HG) functions and second harmonic generation theory reproduces well the patterns both in the near- and far-field which correspond to the intensity distribution in coordinate and momentum spaces, respectively. Considering the analogy of wave functions of the transverse HG mode and 2D harmonic oscillator, we propose that the simple monolithic SFD lasers can be used for developing of new materials and devices and testing 2D quantum mechanical theories.

  19. Spatial reflection patterns of iridescent wings of male pierid butterflies: curved scales reflect at a wider angle than flat scales.

    Science.gov (United States)

    Pirih, Primož; Wilts, Bodo D; Stavenga, Doekele G

    2011-10-01

    The males of many pierid butterflies have iridescent wings, which presumably function in intraspecific communication. The iridescence is due to nanostructured ridges of the cover scales. We have studied the iridescence in the males of a few members of Coliadinae, Gonepteryx aspasia, G. cleopatra, G. rhamni, and Colias croceus, and in two members of the Colotis group, Hebomoia glaucippe and Colotis regina. Imaging scatterometry demonstrated that the pigmentary colouration is diffuse whereas the structural colouration creates a directional, line-shaped far-field radiation pattern. Angle-dependent reflectance measurements demonstrated that the directional iridescence distinctly varies among closely related species. The species-dependent scale curvature determines the spatial properties of the wing iridescence. Narrow beam illumination of flat scales results in a narrow far-field iridescence pattern, but curved scales produce broadened patterns. The restricted spatial visibility of iridescence presumably plays a role in intraspecific signalling.

  20. Modification of parabolic dish antenna pattern using two symmetrically placed circular flat plates

    Science.gov (United States)

    Thorpe, Glen C.

    1987-12-01

    This study aims to formulate a method of predicting the far field pattern of a parabolic dish antenna with two moveable flat plates mounted symmetrically on either side of the feed horn. The approach taken has been to first analyze the radiation pattern of the antenna with the disks at certain heights out from the surface of the dish. To do this the near-field radiation in amplitude and phase was measured over a plane surface in the near-field and the values were then transformed into the far field using a Fast Fourier Transform. Far field pattern values of the antenna were directly measured for each setting of the plates. The results obtained from the Fast Fourier Transform of the near field data were in good agreement with the values obtained by measurement. Finally, an approximate model of the antenna was developed and implemented as a computer program. This model, while relatively unsophisticated, provided some insights into the changes in the near field phase distribution caused by the moveable circular flat plates.

  1. Unfocused beam patterns in nonattenuating and attenuating fluids

    International Nuclear Information System (INIS)

    Goldstein, Albert

    2004-01-01

    The most important aspect of an ultrasound measuring system is knowledge of the transducer beam pattern. At all depths accurate single integral equations have been derived for the full beam pattern of steady state unfocused circular flat piston sources radiating into nonattenuating and attenuating fluids. The axial depth of the beginning of the unattenuated beam pattern far field is found to be at 6.41Y 0 . The unattenuated single integral equations are identical to a Jinc function directivity term at this and deeper depths. For attenuating fluids values of α and z are found that permit the attenuated axial pressure to be represented by a plane wave multiplicative exponential attenuation factor. This knowledge will aid in the experimental design of highly accurate attenuation measurements. Accurate single integral equations for the attenuated full beam pattern are derived using complex Bessel functions

  2. Effect of Micro-Bubbles in Water on Beam Patterns of Parametric Array

    Science.gov (United States)

    Hashiba, Kunio; Masuzawa, Hiroshi

    2003-05-01

    The improvement in efficiency of a parametric array by nonlinear oscillation of micro-bubbles in water is studied in this paper. The micro-bubble oscillation can increase the nonlinear coefficient of the acoustic medium. The amplitude of the difference-frequency wave along the longitudinal axis and its beam patterns in the field including the layer with micro-bubbles were analyzed using a Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation. As a result, the largest improvement in efficiency was obtained and a narrow parametric beam was formed by forming a layer with micro-bubbles in front of a parametric sound radiator as thick as about the shock formation distance. If the layer becomes significantly thicker than the distance, the beam of the difference-frequency wave in the far-field will become broader. If the layer is significantly thinner than the distance, the intensity level of the wave in the far-field will be too low.

  3. Beam Pattern Analysis of the Plate-type Waveguide Sensor for Under-Sodium Viewing

    International Nuclear Information System (INIS)

    Kim, Hoewoong; Joo, Youngsang; Park, Changgyu; Kim, Jongbum

    2013-01-01

    Sensor for under-sodium viewing (USV) in a sodium-cooled fast reactor (SFR) has been developed. In the developed WG sensor approach, the A0 mode Lamb wave is used and a thin beryllium layer is coated on the waveguide surface to improve the ultrasonic radiation ability in a sodium environment. In this work, the beam pattern radiated from the developed plate-type WG sensor is investigated analytically to understand and predict the ultrasonic beam radiation property of the WG sensor in a liquid. Analytic calculations to obtain beam patterns for two kinds of WG sensors with and without beryllium coating layers were carried out and the results were compared with those obtained by experiments. In this work, the beam pattern of the plate-type WG sensor for USV was investigated analytically. Employing the far-field approximation, the acoustic response at a given measurement position was calculated for the plate-type WG sensors with and without beryllium coating layers. The beam patterns of WG sensors were predicted by the analytic calculation and the corresponding experiments were carried out. The results showed that the far-field beam pattern radiated from the plate-type WG sensor could be well predicted by an analytic calculation. The radiation beam angles obtained by the analytical calculation were in good agreement with those obtained by experiments

  4. Polyhedral patterns

    KAUST Repository

    Jiang, Caigui; Tang, Chengcheng; Vaxman, Amir; Wonka, Peter; Pottmann, Helmut

    2015-01-01

    We study the design and optimization of polyhedral patterns, which are patterns of planar polygonal faces on freeform surfaces. Working with polyhedral patterns is desirable in architectural geometry and industrial design. However, the classical

  5. Polyhedral patterns

    KAUST Repository

    Jiang, Caigui

    2015-10-27

    We study the design and optimization of polyhedral patterns, which are patterns of planar polygonal faces on freeform surfaces. Working with polyhedral patterns is desirable in architectural geometry and industrial design. However, the classical tiling patterns on the plane must take on various shapes in order to faithfully and feasibly approximate curved surfaces. We define and analyze the deformations these tiles must undertake to account for curvature, and discover the symmetries that remain invariant under such deformations. We propose a novel method to regularize polyhedral patterns while maintaining these symmetries into a plethora of aesthetic and feasible patterns.

  6. Specialization Patterns

    DEFF Research Database (Denmark)

    Schultz, Ulrik Pagh; Lawall, Julia Laetitia; Consel, Charles

    2000-01-01

    Design patterns offer many advantages for software development, but can introduce inefficiency into the final program. Program specialization can eliminate such overheads, but is most effective when targeted by the user to specific bottlenecks. Consequently, we propose that these concepts...... are complementary. Program specialization can optimize programs written using design patterns, and design patterns provide information about the program structure that can guide specialization. Concretely, we propose specialization patterns, which describe how to apply program specialization to optimize uses...... of design patterns. In this paper, we analyze the specialization opportunities provided by specific uses of design patterns. Based on the analysis of each design pattern, we define the associated specialization pattern. These specialization opportunities can be declared using the specialization classes...

  7. Specialization Patterns

    OpenAIRE

    Schultz , Ulrik Pagh; Lawall , Julia ,; Consel , Charles

    1999-01-01

    Design patterns offer numerous advantages for software development, but can introduce inefficiency into the finished program. Program specialization can eliminate such overheads, but is most effective when targeted by the user to specific bottlenecks. Consequently, we propose to consider program specialization and design patterns as complementary concepts. On the one hand, program specialization can optimize object-oriented programs written using design patterns. On the other hand, design pat...

  8. Pattern recognition

    CERN Document Server

    Theodoridis, Sergios

    2003-01-01

    Pattern recognition is a scientific discipline that is becoming increasingly important in the age of automation and information handling and retrieval. Patter Recognition, 2e covers the entire spectrum of pattern recognition applications, from image analysis to speech recognition and communications. This book presents cutting-edge material on neural networks, - a set of linked microprocessors that can form associations and uses pattern recognition to ""learn"" -and enhances student motivation by approaching pattern recognition from the designer's point of view. A direct result of more than 10

  9. Geodesic patterns

    KAUST Repository

    Pottmann, Helmut; Huang, Qixing; Deng, Bailin; Schiftner, Alexander; Kilian, Martin; Guibas, Leonidas J.; Wallner, Johannes

    2010-01-01

    Geodesic curves in surfaces are not only minimizers of distance, but they are also the curves of zero geodesic (sideways) curvature. It turns out that this property makes patterns of geodesics the basic geometric entity when dealing with the cladding of a freeform surface with wooden panels which do not bend sideways. Likewise a geodesic is the favored shape of timber support elements in freeform architecture, for reasons of manufacturing and statics. Both problem areas are fundamental in freeform architecture, but so far only experimental solutions have been available. This paper provides a systematic treatment and shows how to design geodesic patterns in different ways: The evolution of geodesic curves is good for local studies and simple patterns; the level set formulation can deal with the global layout of multiple patterns of geodesics; finally geodesic vector fields allow us to interactively model geodesic patterns and perform surface segmentation into panelizable parts. © 2010 ACM.

  10. Foam patterns

    Science.gov (United States)

    Chaudhry, Anil R; Dzugan, Robert; Harrington, Richard M; Neece, Faurice D; Singh, Nipendra P; Westendorf, Travis

    2013-11-26

    A method of creating a foam pattern comprises mixing a polyol component and an isocyanate component to form a liquid mixture. The method further comprises placing a temporary core having a shape corresponding to a desired internal feature in a cavity of a mold and inserting the mixture into the cavity of the mold so that the mixture surrounds a portion of the temporary core. The method optionally further comprises using supporting pins made of foam to support the core in the mold cavity, with such pins becoming integral part of the pattern material simplifying subsequent processing. The method further comprises waiting for a predetermined time sufficient for a reaction from the mixture to form a foam pattern structure corresponding to the cavity of the mold, wherein the foam pattern structure encloses a portion of the temporary core and removing the temporary core from the pattern independent of chemical leaching.

  11. Geodesic patterns

    KAUST Repository

    Pottmann, Helmut

    2010-07-26

    Geodesic curves in surfaces are not only minimizers of distance, but they are also the curves of zero geodesic (sideways) curvature. It turns out that this property makes patterns of geodesics the basic geometric entity when dealing with the cladding of a freeform surface with wooden panels which do not bend sideways. Likewise a geodesic is the favored shape of timber support elements in freeform architecture, for reasons of manufacturing and statics. Both problem areas are fundamental in freeform architecture, but so far only experimental solutions have been available. This paper provides a systematic treatment and shows how to design geodesic patterns in different ways: The evolution of geodesic curves is good for local studies and simple patterns; the level set formulation can deal with the global layout of multiple patterns of geodesics; finally geodesic vector fields allow us to interactively model geodesic patterns and perform surface segmentation into panelizable parts. © 2010 ACM.

  12. Design, Analysis, and Verification of Ka-Band Pattern Reconfigurable Patch Antenna Using RF MEMS Switches

    Directory of Open Access Journals (Sweden)

    Zhongliang Deng

    2016-08-01

    Full Text Available This paper proposes a radiating pattern reconfigurable antenna by employing RF Micro-electromechanical Systems (RF MEMS switches. The antenna has a low profile and small size of 4 mm × 5 mm × 0.4 mm, and mainly consists of one main patch, two assistant patches, and two RF MEMS switches. By changing the RF MEMS switches operating modes, the proposed antenna can switch among three radiating patterns (with main lobe directions of approximately −17.0°, 0° and +17.0° at 35 GHz. The far-field vector addition model is applied to analyse the pattern. Comparing the measured results with analytical and simulated results, good agreements are obtained.

  13. Search Patterns

    CERN Document Server

    Morville, Peter

    2010-01-01

    What people are saying about Search Patterns "Search Patterns is a delight to read -- very thoughtful and thought provoking. It's the most comprehensive survey of designing effective search experiences I've seen." --Irene Au, Director of User Experience, Google "I love this book! Thanks to Peter and Jeffery, I now know that search (yes, boring old yucky who cares search) is one of the coolest ways around of looking at the world." --Dan Roam, author, The Back of the Napkin (Portfolio Hardcover) "Search Patterns is a playful guide to the practical concerns of search interface design. It cont

  14. Root patterning

    NARCIS (Netherlands)

    Scheres, Ben; Laskowski, Marta

    2016-01-01

    The mechanisms that pattern lateral root primordial are essential for the elaboration of root system architecture, a trait of key importance for future crop breeding. But which are most important: periodic or local cues? In this issue of Journal of Experimental Botany (pages 1411-1420), Kircher

  15. Granular patterns

    CERN Document Server

    Aranson, Igor S

    2009-01-01

    This title presents a review of experiments and novel theoretical concepts needed to understand the mechanisms of pattern formation in granular materials. An effort is made to connect concepts and ideas developed in granular physics with new emergent fields, especially in biology, such as cytoskeleton dynamics.

  16. Study of high speed complex number algorithms. [for determining antenna for field radiation patterns

    Science.gov (United States)

    Heisler, R.

    1981-01-01

    A method of evaluating the radiation integral on the curved surface of a reflecting antenna is presented. A three dimensional Fourier transform approach is used to generate a two dimensional radiation cross-section along a planer cut at any angle phi through the far field pattern. Salient to the method is an algorithm for evaluating a subset of the total three dimensional discrete Fourier transform results. The subset elements are selectively evaluated to yield data along a geometric plane of constant. The algorithm is extremely efficient so that computation of the induced surface currents via the physical optics approximation dominates the computer time required to compute a radiation pattern. Application to paraboloid reflectors with off-focus feeds in presented, but the method is easily extended to offset antenna systems and reflectors of arbitrary shapes. Numerical results were computed for both gain and phase and are compared with other published work.

  17. Proof patterns

    CERN Document Server

    Joshi, Mark

    2015-01-01

    This innovative textbook introduces a new pattern-based approach to learning proof methods in the mathematical sciences. Readers will discover techniques that will enable them to learn new proofs across different areas of pure mathematics with ease. The patterns in proofs from diverse fields such as algebra, analysis, topology and number theory are explored. Specific topics examined include game theory, combinatorics, and Euclidean geometry, enabling a broad familiarity. The author, an experienced lecturer and researcher renowned for his innovative view and intuitive style, illuminates a wide range of techniques and examples from duplicating the cube to triangulating polygons to the infinitude of primes to the fundamental theorem of algebra. Intended as a companion for undergraduate students, this text is an essential addition to every aspiring mathematician’s toolkit.

  18. Laser-induced speckle scatter patterns in Bacillus colonies

    Directory of Open Access Journals (Sweden)

    Huisung eKim

    2014-10-01

    Full Text Available Label-free bacterial colony phenotyping technology called BARDOT (BActerial Rapid Detection using Optical scattering Technology provided successful classification of several different bacteria at the genus, species, and serovar level. Recent experiments with colonies of Bacillus species provided strikingly different characteristics of elastic light scatter (ELS patterns, which were comprised of random speckles compared to other bacteria, which are dominated by concentric rings and spokes. Since this laser-based optical sensor interrogates the whole volume of the colony, 3-D information of micro- and macro-structures are all encoded in the far-field scatter patterns. Here, we present a theoretical model explaining the underlying mechanism of the speckle formation by the colonies from Bacillus species. Except for Bacillus polymyxa, all Bacillus spp. produced random bright spots on the imaging plane, which presumably dependent on the cellular and molecular organization and content within the colony. Our scatter model-based analysis revealed that colony spread resulting in variable surface roughness can modify the wavefront of the scatter field. As the center diameter of the Bacillus spp. colony grew from 500 μm to 900 μm, average speckles area decreased 2-fold and the number of small speckles increased 7-fold. In conclusion, as Bacillus colony grows, the average speckle size in the scatter pattern decreases and the number of smaller speckle increases due to the swarming growth characteristics of bacteria within the colony.

  19. Modal radiation patterns of baffled circular plates and membranes.

    Science.gov (United States)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain; Jensen, Jørgen Arendt

    2014-05-01

    The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation force, which is used as a sound receiver in any medium or as a sound transmitter in a gaseous medium. A general, concise expression is given for the radiation pattern of any mode of the membrane and the plate with arbitrary boundary conditions. Specific solutions are given for the four special cases of a plate with clamped, simply supported, and free edge boundary conditions as well as for the membrane. For all non-axisymmetric modes, the velocity potential along the axis of the radiator is found to be strictly zero. In the long wavelength limit, the radiation pattern of all axisymmetric modes approaches that of a monopole, while the non-axisymmetric modes exhibit multipole behavior. Numerical results are also given, demonstrating the implications of having non-axisymmetric excitation using both a point excitation with varying eccentricity and a homogeneous excitation acting on half of the circular radiator.

  20. Pattern classification

    CERN Document Server

    Duda, Richard O; Stork, David G

    2001-01-01

    The first edition, published in 1973, has become a classic reference in the field. Now with the second edition, readers will find information on key new topics such as neural networks and statistical pattern recognition, the theory of machine learning, and the theory of invariances. Also included are worked examples, comparisons between different methods, extensive graphics, expanded exercises and computer project topics. An Instructor's Manual presenting detailed solutions to all the problems in the book is available from the Wiley editorial department.

  1. Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

    International Nuclear Information System (INIS)

    J.P. Nicot

    2000-01-01

    The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the WP. This calculation supports disposal criticality analysis and has been prepared in accordance with AP-3.12Q, Calculations (Ref. 49). This calculation uses results from Ref. 4 on actinide accumulation in the invert and more generally does reference heavily the cited calculation. In addition to the information provided in this calculation, the reader is referred to the cited calculation for a more thorough treatment of items applying to both the invert and fracture system such as the choice of the thermodynamic database, the composition of J-13 well water, tuff composition, dissolution rate laws, Pu(OH) 4 solubility and also for details on the source term composition. The flow conditions (seepage rate, water velocity in fractures) in the drift and the fracture system beneath initially referred to the TSPA-VA because this work was prepared before the release of the work feeding the TSPA-SR. Some new information feeding the TSPA-SR has since been included. Similarly, the soon-to-be-qualified thermodynamic database data0.ymp has not been released yet

  2. FDTD computation of temperature elevation in the elderly for far-field RF exposures

    International Nuclear Information System (INIS)

    Nomura, Tomoki; Laakso, Ilkka; Hirata, Akimasa

    2014-01-01

    Core temperature elevation and perspiration in younger and older adults is investigated for plane-wave exposure at whole-body averaged specific absorption rate of 0.4 W kg -1 . Numeric Japanese male model is considered together with a thermo-regulatory response formula proposed in the authors' previous study. The frequencies considered were at 65 MHz and 2 GHz where the total power absorption in humans becomes maximal for the allowable power density prescribed in the international guidelines. From the computational results used here, the core temperature elevation in the older adult model was larger than that in the younger one at both frequencies. The reason for this difference is attributable to the difference of sweating, which is originated from the difference in the threshold activating the sweating and the decline in sweating in the legs. (authors)

  3. Far field nuclear fallout experience and countermeasure strategy: A cost-benefit re-appraisal

    International Nuclear Information System (INIS)

    Harbitz, O.; Reitan, J.B.; Strand, P.

    1997-01-01

    The time of the year (April, May) when the fallout occurred, had influence on the consequences. In spring no animals were out grazing and almost no standing crops could receive direct surface contamination. However, uptake and the transfer in the semi-natural ecosystem became considerable important. In semi-natural ecosystems, soils often have a low mineral content and very little clay and this usually means less findings of the radiocaesium. Even before the Chernobyl accident occurred, it was known that the root uptake of radiocaesium in a semi-natural ecosystem was higher than average in agricultural ecosystems

  4. Far-Field Superresolution of Thermal Electromagnetic Sources at the Quantum Limit.

    Science.gov (United States)

    Nair, Ranjith; Tsang, Mankei

    2016-11-04

    We obtain the ultimate quantum limit for estimating the transverse separation of two thermal point sources using a given imaging system with limited spatial bandwidth. We show via the quantum Cramér-Rao bound that, contrary to the Rayleigh limit in conventional direct imaging, quantum mechanics does not mandate any loss of precision in estimating even deep sub-Rayleigh separations. We propose two coherent measurement techniques, easily implementable using current linear-optics technology, that approach the quantum limit over an arbitrarily large range of separations. Our bound is valid for arbitrary source strengths, all regions of the electromagnetic spectrum, and for any imaging system with an inversion-symmetric point-spread function. The measurement schemes can be applied to microscopy, optical sensing, and astrometry at all wavelengths.

  5. Determination of irradiated uranium in far-field contaminated areas of Belarus

    International Nuclear Information System (INIS)

    Mironov, V.; Pribylev, S.; Hotchkis, M.; Child, D.

    2006-01-01

    The possibility of using U 236 as an indicator for irradiated uranium is shown. The sensitivity of AMS is high enough for measurements of 236 U/ 238 U ratios down to 10 -9 on micrograms of uranium and therefore for the detection of Chernobyl originated uranium in the remote regions of radioactive fallout. (authors)

  6. Statistical prediction of far-field wind-turbine noise, with probabilistic characterization of atmospheric stability

    DEFF Research Database (Denmark)

    Kelly, Mark C.; Barlas, Emre; Sogachev, Andrey

    2018-01-01

    Here we provide statistical low-order characterization of noise propagation from a single wind turbine, as affected by mutually interacting turbine wake and environmental conditions. This is accomplished via a probabilistic model, applied to an ensemble of atmospheric conditions based upon......; the latter solves Reynolds-Averaged Navier-Stokes equations of momentum and temperature, including the effects of stability and the ABL depth, along with the drag due to the wind turbine. Sound levels are found to be highest downwind for modestly stable conditions not atypical of mid-latitude climates...

  7. A fully analytic treatment of resonant inductive coupling in the far field

    Science.gov (United States)

    Sedwick, Raymond J.

    2012-02-01

    For the application of resonant inductive coupling for wireless power transfer, fabrication of flat spiral coils using ribbon wire allows for analytic expressions of the capacitance and inductance of the coils and therefore the resonant frequency. The expressions can also be used in an approximate way for the analysis of coils constructed from cylindrical wire. Ribbon wire constructed from both standard metals as well as high temperature superconducting material is commercially available, so using these derived expressions as a basis, a fully analytic treatment is presented that allows for design trades to be made for hybrid designs incorporating either technology. The model is then extended to analyze the performance of the technology as applied to inductively coupled communications, which has been demonstrated as having an advantage in circumstances where radiated signals would suffer unacceptable levels of attenuation.

  8. A fully analytic treatment of resonant inductive coupling in the far field

    International Nuclear Information System (INIS)

    Sedwick, Raymond J.

    2012-01-01

    For the application of resonant inductive coupling for wireless power transfer, fabrication of flat spiral coils using ribbon wire allows for analytic expressions of the capacitance and inductance of the coils and therefore the resonant frequency. The expressions can also be used in an approximate way for the analysis of coils constructed from cylindrical wire. Ribbon wire constructed from both standard metals as well as high temperature superconducting material is commercially available, so using these derived expressions as a basis, a fully analytic treatment is presented that allows for design trades to be made for hybrid designs incorporating either technology. The model is then extended to analyze the performance of the technology as applied to inductively coupled communications, which has been demonstrated as having an advantage in circumstances where radiated signals would suffer unacceptable levels of attenuation. - Highlights: ► An analytic framework finds power and efficiency for resonant inductive coupling. ► The framework supports superconducting, resistive and dielectric elements. ► Maximum power transfer occurs at an efficiency of 50% when in close proximity. ► A 100 turn superconducting design achieves 10% efficiency out to 280 coil radii. ► The system response to narrow band amplitude modulation is modeled and presented.

  9. Near-field/far-field azimuth and elevation angle estimation using a single vector hydrophone

    Czech Academy of Sciences Publication Activity Database

    Tichavský, Petr; Wong, K. T.; Zoltowski, M.

    2001-01-01

    Roč. 49, č. 11 (2001), s. 2498-2510 ISSN 1053-587X R&D Projects: GA ČR GA102/97/0466; GA ČR GA102/01/0021 Institutional research plan: AV0Z1075907 Keywords : acoustic signal processing * array signal processing * direction-of-arrival estimation Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.268, year: 2001

  10. Numerical simulation of the sound reflection effects of noise barriers in near and far field

    NARCIS (Netherlands)

    Lutgendorf, D.; Roo, F. de; Eerden, F.J.M. van der; Jean, P.; Ecotière, D.; Dutilleux, G.

    2011-01-01

    This paper deals with the first stages of the development of a new test method for evaluating the reflectivity performance of noise barriers. The reflectivity performance describes the increase in sound level at a receiver due to the presence of the noise barrier. First the current test method for

  11. Analytical calculation on the determination of steep side wall angles from far field measurements

    Science.gov (United States)

    Cisotto, Luca; Pereira, Silvania F.; Urbach, H. Paul

    2018-06-01

    In the semiconductor industry, the performance and capabilities of the lithographic process are evaluated by measuring specific structures. These structures are often gratings of which the shape is described by a few parameters such as period, middle critical dimension, height, and side wall angle (SWA). Upon direct measurement or retrieval of these parameters, the determination of the SWA suffers from considerable inaccuracies. Although the scattering effects that steep SWAs have on the illumination can be obtained with rigorous numerical simulations, analytical models constitute a very useful tool to get insights into the problem we are treating. In this paper, we develop an approach based on analytical calculations to describe the scattering of a cliff and a ridge with steep SWAs. We also propose a detection system to determine the SWAs of the structures.

  12. Coupled near-field and far-field exposure assessment framework for chemicals in consumer products

    DEFF Research Database (Denmark)

    Fantke, Peter; Ernstoff, Alexi; Huang, Lei

    2016-01-01

    Humans can be exposed to chemicals in consumer products through product use and environmental emissions over the product life cycle. Exposure pathways are often complex, where chemicals can transfer directly from products to humans during use or exchange between various indoor and outdoor...... compartments until sub-fractions reach humans. To consistently evaluate exposure pathways along product life cycles, a flexible mass balance-based assessment framework is presented structuring multimedia chemical transfers in a matrix of direct inter-compartmental transfer fractions. By matrix inversion, we...

  13. RESEARCH OF THE THICKNESS NOISE OF MAIN ROTOR IN FAR FIELD

    Directory of Open Access Journals (Sweden)

    V. A. Golovkin

    2014-01-01

    Full Text Available The results of acoustic characteristics of the main rotor, in particular the thickness noise are presented. The influences of geometric and kinematic parameters on the thickness noise are investigated.

  14. Stealth metamaterial objects characterized in the far field by Radar Cross Section measurements

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Fan, K.; Strikwerda, A. C.

    Reflection spectra and radar cross sections (RCS) at terahertz frequencies are measured on structures incorporating absorbing metamaterials. Reduction of the RCS by the factor of 375 at the resonant frequencies is observed.......Reflection spectra and radar cross sections (RCS) at terahertz frequencies are measured on structures incorporating absorbing metamaterials. Reduction of the RCS by the factor of 375 at the resonant frequencies is observed....

  15. New three-dimensional far-field potential repository thermomechanical calculations

    International Nuclear Information System (INIS)

    Hardy, M.P.; Bai, M.; Goodrich, R.R.; Lin, M.; Carlisle, S.; Bauer, S.J.

    1993-03-01

    The thermomechanical effect on the exploratory ramps, drifts, and shafts as a result of high-level nuclear waste disposal is examined using a three-dimensional thermo-elastic model. The repository layout modeled is based on the use of mechanical mining of all excavations with equivalent waste emplacement areal power densities of 57 and 80 kW/acre. Predicted temperatures and stress changes for the north and south access drifts, east main drift, east-west exploratory drift, the north and south Calico Hills access ramps, the Calico Hills north-south exploratory drift, and the optional exploratory studies facility and man and materials shafts are presented for times 10, 35, 50, 100, 300, 500, 1000, 2000, 5000, and 10,000 years after the start of waste emplacement. The study indicates that the east-west exploratory drift at the repository horizon is subject to the highest thermomechanical impact because it is located closest the buried waste canisters. For most exploratory openings, the thermally induced temperatures and stresses tend to reach the maximum magnitudes at approximately 1000 years after waste emplacement

  16. Efficient voice activity detection in reverberant enclosures using far field microphones

    DEFF Research Database (Denmark)

    Petsatodis, Theodore; Boukis, Christos

    2009-01-01

    An algorithm suitable for voice activity detection under reverberant conditions is proposed in this paper. Due to the use of far-filed microphones the proposed solution processes speech signals of highly-varying intensity and signal to noise ratio, that are contaminated with several echoes....... The core of the system is a pair of Hidden Markov Models, that effectively model the speech presence and speech absence situations. To minimise mis-detections an adaptive threshold is used, while a hang-over scheme caters for the intra-frame correlation of speech signals. Experimental results conducted...

  17. Two-dimensional transient far-field analysis for the excess temperature from an arbitrary source

    Energy Technology Data Exchange (ETDEWEB)

    Witten, A.J.; Long, E.C.

    1978-07-01

    An analytic solution is presented for the two-dimensional time-dependent advective diffusion equation governing the distribution of excess temperature in a river of uniform width, depth, and downstream flow. The solution is also applicable to a straight coastline with uniform longshore flow. Exact solutions are obtained for a point heat source and a particular line heat source, while an approximate representation is given for an arbitrary time-varying heat source. These solutions are incorporated into a computer program which calculates excess temperature and time rate-of-change of excess temperature in a river or coast as a result of waste heat discharged from various transient sources.

  18. Learning for autonomous navigation : extrapolating from underfoot to the far field

    Science.gov (United States)

    Matthies, Larry; Turmon, Michael; Howard, Andrew; Angelova, Anelia; Tang, Benyang; Mjolsness, Eric

    2005-01-01

    Autonomous off-road navigation of robotic ground vehicles has important applications on Earth and in space exploration. Progress in this domain has been retarded by the limited lookahead range of 3-D sensors and by the difficulty of preprogramming systems to understand the traversability of the wide variety of terrain they can encounter. Enabling robots to learn from experience may alleviate both of these problems. We define two paradigms for this, learning from 3-D geometry and learning from proprioception, and describe initial instantiations of them we have developed under DARPA and NASA programs. Field test results show promise for learning traversability of vegetated terrain, learning to extend the lookahead range of the vision system, and learning how slip varies with slope.

  19. The far field migration of radionuclides in two dimensional groundwater flows though geologic media

    International Nuclear Information System (INIS)

    Ting, D.K.S.; Chambre, P.

    1985-01-01

    An analytical method to model the radionuclides migration in a two dimensional groundwater flor through geologic media has been developed and implemented into the computer code UCBNE21. Using this method, the potential hazard to the biosphere posed by the accidental release of radionuclides from a candidate repository site (WIPP) is determined. I-129 and Ra-226 are potentially the most hazardous nuclides in these sites but their discharge into the biosphere will not result in concentrations larger than their maximum permissible concentrations. (Author) [pt

  20. NEAR- AND FAR-FIELD RESPONSE TO COMPACT ACOUSTIC SOURCES IN STRATIFIED CONVECTION ZONES

    International Nuclear Information System (INIS)

    Cally, Paul S.

    2013-01-01

    The role of the acoustic continuum associated with compact sources in the Sun's interior wave field is explored for a simple polytropic model. The continuum produces a near-field acoustic structure—the so-called acoustic jacket—that cannot be represented by a superposition of discrete normal modes. Particular attention is paid to monochromatic point sources of various frequency and depth, and to the surface velocity power that results, both in the discrete f- and p-mode spectrum and in the continuum. It is shown that a major effect of the continuum is to heal the surface wave field produced by compact sources, and therefore to hide them from view. It is found that the continuous spectrum is not a significant contributor to observable inter-ridge seismic power.

  1. NEAR- AND FAR-FIELD RESPONSE TO COMPACT ACOUSTIC SOURCES IN STRATIFIED CONVECTION ZONES

    Energy Technology Data Exchange (ETDEWEB)

    Cally, Paul S., E-mail: paul.cally@monash.edu [Monash Centre for Astrophysics and School of Mathematical Sciences, Monash University, Clayton, Victoria 3800 (Australia)

    2013-05-01

    The role of the acoustic continuum associated with compact sources in the Sun's interior wave field is explored for a simple polytropic model. The continuum produces a near-field acoustic structure-the so-called acoustic jacket-that cannot be represented by a superposition of discrete normal modes. Particular attention is paid to monochromatic point sources of various frequency and depth, and to the surface velocity power that results, both in the discrete f- and p-mode spectrum and in the continuum. It is shown that a major effect of the continuum is to heal the surface wave field produced by compact sources, and therefore to hide them from view. It is found that the continuous spectrum is not a significant contributor to observable inter-ridge seismic power.

  2. Compact resonator on leather for nonradiative inductive power transfer and far-field data links

    Science.gov (United States)

    Monti, G.; Corchia, L.; De Benedetto, E.; Tarricone, L.

    2016-06-01

    In this paper, a wearable resonator suitable to be used for both power and data transmission is presented. The basic element is a complementary split ring resonator that has been optimized to operate both as a dipole-like antenna at 2.45 GHz and as the receiver of a resonant energy link operating at 915 MHz when coupled with an identical external resonator connected to a power source. Experimental data referring to a prototype fabricated by using a conductive adhesive fabric on a leather substrate are reported and discussed. With regard to the wireless resonant energy link (WREL), it is demonstrated that at 915 MHz, the RF-to-RF power transfer efficiency of the link is approximately 78.1%. As for the performance obtained when the resonator is used as an antenna, a gain of approximately -0.43 dB was obtained. Additionally, the performance of the proposed link when connected to a Power Management Unit (PMU) that converts the radio frequency (RF) energy received by the wearable resonator into DC energy that can be directly used for recharging a thin-film battery was also investigated. Experimental tests were performed in order to evaluate both the total efficiency of the wireless charger (i.e., the WREL link connected to the PMU) and the time necessary to recharge a THINERGY MEC201 battery. The obtained results demonstrate the feasibility of using the proposed WREL for implementing a battery charger; in particular, by providing an input power higher than 8 dBm, the time necessary to recharge the considered thin-film battery is shorter than 38 min.

  3. FDTD computation of temperature elevation in the elderly for far-field RF exposures.

    Science.gov (United States)

    Nomura, Tomoki; Laakso, Ilkka; Hirata, Akimasa

    2014-03-01

    Core temperature elevation and perspiration in younger and older adults is investigated for plane-wave exposure at whole-body averaged specific absorption rate of 0.4 W kg(-1). Numeric Japanese male model is considered together with a thermoregulatory response formula proposed in the authors' previous study. The frequencies considered were at 65 MHz and 2 GHz where the total power absorption in humans becomes maximal for the allowable power density prescribed in the international guidelines. From the computational results used here, the core temperature elevation in the older adult model was larger than that in the younger one at both frequencies. The reason for this difference is attributable to the difference of sweating, which is originated from the difference in the threshold activating the sweating and the decline in sweating in the legs.

  4. Remote sensing of chlorophyll a fluorescence of vegetation canopies. 1. Near and far field measurement techniques

    International Nuclear Information System (INIS)

    Cecchi, G.; Mazzinghi, P.; Pantani, L.; Valentini, R.; Tirelli, D.; De Angelis, P.

    1994-01-01

    This article presents instruments and techniques, used in several vegetation monitoring experiments. Simultaneous monitoring was performed with different approaches, including fluorescence lidar and passive remote sensing, leaf level reflectance, and laser fluorimetry, and compared with physiological measurements. Most of the instrumentation described was designed and built for this application. Experiments were carried out in the laboratory and in the field, to investigate the relationship between chlorophyll fluorescence spectra and plant ecophysiology. Remote sensing, spectroscopy, and ecophysiology data were then collected by an intensive research team, joining different experiences and working in national and international projects

  5. modelling of far modelling of far-field mixing o field mixing o ambient

    African Journals Online (AJOL)

    User

    his study sought to describe the dynamics of advective and dispersive tr .... focused on environmental policy designs targeted at ... consequences such as welfare loss of outright ban on polluting ... optimal DO level. ... carried out a similar study to model the shadow price .... As A varies, we have a family of curves depicted in.

  6. Fuel-Air Explosive Simulation of Far-Field Nuclear Airblasts.

    Science.gov (United States)

    1979-12-31

    Blastwave Simulator," Sixieme Symposium International sur Les A19 plications Militaires de La Simulation de Souffle, Centre D’Etudes de Gramat , Gramat ... Gramat , Gramat , France, p. 4.2.1, June 1979. 207 7............................. 64. Cooperwaithe, M. and Zwisler, W. H., "TIGER Computer Program

  7. Lr-Lp Stability of the Incompressible Flows with Nonzero Far-Field Velocity

    Directory of Open Access Journals (Sweden)

    Jaiok Roh

    2011-01-01

    Full Text Available We consider the stability of stationary solutions w for the exterior Navier-Stokes flows with a nonzero constant velocity u∞ at infinity. For u∞=0 with nonzero stationary solution w, Chen (1993, Kozono and Ogawa (1994, and Borchers and Miyakawa (1995 have studied the temporal stability in Lp spaces for 11 and obtain Lr-Lp stability as Kozono and Ogawa and Borchers and Miyakawa obtained for u∞=0.

  8. Probing the dispersion properties of 1D nanophotonic waveguides with far-field Fourier optics

    DEFF Research Database (Denmark)

    Le Thomas, N.; Jágerská, J.; Houdré, R.

    2008-01-01

    We present an advanced Fourier space imaging technique to probe guided light in nanophotonic structures with an effective numerical aperture of 2.5. This superresolution technique allows us to successfully investigate the dispersive properties of 1D nanowaveguides such as photonic crystal W1...

  9. Robustness of the far-field response of nonlocal plasmonic ensembles

    DEFF Research Database (Denmark)

    Tserkezis, Christos; Maack, Johan Rosenkrantz; Liu, Zhaowei

    2016-01-01

    Contrary to classical predictions, the optical response of few-nm plasmonic particles depends on particle size due to effects such as nonlocality and electron spill-out. Ensembles of such nanoparticles are therefore expected to exhibit a nonclassical inhomogeneous spectral broadening due to size...... distribution. For a normal distribution of free-electron nanoparticles, and within the simple nonlocal hydrodynamic Drude model, both the nonlocal blueshift and the plasmon linewidth are shown to be considerably affected by ensemble averaging. Size-variance effects tend however to conceal nonlocality...... to a lesser extent when the homogeneous size-dependent broadening of individual nanoparticles is taken into account, either through a local size-dependent damping model or through the Generalized Nonlocal Optical Response theory. The role of ensemble averaging is further explored in realistic distributions...

  10. Verification and validation of models: far-field modelling of radionuclide migration

    International Nuclear Information System (INIS)

    Porter, J.D.; Herbert, A.W.; Clarke, D.S.; Roe, P.; Vassilic Melling, D.; Einfeldt, B.; Mackay, R.; Glendinning, R.

    1992-01-01

    The aim of this project was to improve the capability, efficiency and realism of the NAMMU and NAPSAC codes, which simulate groundwater flow and solute transport. Using NAMMU, various solution methods for non linear problems were investigated. The Broyden method gave a useful reduction in computing time and appeared robust. The relative saving obtained with this method increased with the problem size. This was also the case when parameter stepping was used. The existing empirical sorption models in NAMMU were generalized and a ternary heterogeneous ion exchange model was added. These modifications were tested and gave excellent results. The desirability of coupling NAMMU to an existing geochemical speciation code was assessed

  11. Yucca Mountain Project far-field sorption studies and data needs

    International Nuclear Information System (INIS)

    Meijer, A.

    1990-09-01

    Batch sorption experiments in which radionuclides dissolved in groundwaters from Yucca Mountain were sorbed onto samples of crushed tuff have resulted in a substantial database of sorption coefficients for radionuclides of interest to the repository program. Although this database has been useful in preliminary evaluations of Yucca Mountain as a potential site for a nuclear waste repository, the database has limitations that must be addressed before it can be used for performance assessment calculations in support of a license application for a waste repository. The purpose of this paper is to: review the applicability of simple (constant) sorption coefficients in transport calculations; review and evaluate alternative methods for the derivation of sorption coefficients; summarize and evaluate the present YMP sorption database to identify areas of data sufficiency and significant data gaps; summarize our current understanding of pertinent sorption mechanisms and associated kinetic parameters; evaluate the significance to the YMP of potential problems in the experimental determination and field application of sorption coefficients as enumerated by the NRC (Nuclear Regulatory Commission, 1987) in its technical position paper on sorption; formulate and evaluate strategies for the resolution of NRC concerns regarding experimental problems; and formulate a position on the sorption coefficient database and the level of understanding of sorption mechanisms likely to be required in the licensing application. 75 refs., 1 fig., 2 tabs

  12. Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

    Energy Technology Data Exchange (ETDEWEB)

    J.P. Nicot

    2000-09-29

    The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the WP. This calculation supports disposal criticality analysis and has been prepared in accordance with AP-3.12Q, Calculations (Ref. 49). This calculation uses results from Ref. 4 on actinide accumulation in the invert and more generally does reference heavily the cited calculation. In addition to the information provided in this calculation, the reader is referred to the cited calculation for a more thorough treatment of items applying to both the invert and fracture system such as the choice of the thermodynamic database, the composition of J-13 well water, tuff composition, dissolution rate laws, Pu(OH){sub 4} solubility and also for details on the source term composition. The flow conditions (seepage rate, water velocity in fractures) in the drift and the fracture system beneath initially referred to the TSPA-VA because this work was prepared before the release of the work feeding the TSPA-SR. Some new information feeding the TSPA-SR has since been included. Similarly, the soon-to-be-qualified thermodynamic database data0.ymp has not been released yet.

  13. Optimization of near and far patterns field in InxGa1-xN Lasers

    International Nuclear Information System (INIS)

    Martín, Juan A.; Mon, E.; Sánchez, M.

    2008-01-01

    The introduction on the market of lasers based on In x Ga 1-x N emitted at short wavelengths (λ = 430-450 nm), has enabled a considerable increase of the density of data storage on optical discs. However, despite the successes in the manufacture of these lasers are still far from being optimized. One of the difficulties present in these structures is the technological difficulty to grow In x Ga 1-x N cladding layers with high aluminum content (x>0.13) and wide enough to ensure the necessary optical confinement. This difficulty is due to the network constant difference between the Al x Ga 1-x N and the GaN and the presence of narrow cladding layers causes the undesirable high-order modes in [1] far field patterns. This paper analyzes the influence of the thickness of the layers that form the structure on the patterns of field near and far In x Ga 1-x N structures with multiple quantum wells in the active area. Structures are compared with staggered and parabolic variation of the refractive index. Found that with appropriate combinations of the thickness of this layer the detrimental effects that appear in from near and far field patterns can be eliminated without the need to grow very wide cladding layers, which represents an alternative solution to this technological problem [2]. [1] M. Onomura et al, IEEE J. Sel. Top. Quantum Electron. 5 (1999) 76. [2] J.A. Martín et al. Superlattices and Microstructures 43 (200 8) 575.

  14. Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Aleš Procházka

    2018-05-01

    Full Text Available Multimodal signal analysis based on sophisticated sensors, efficient communicationsystems and fast parallel processing methods has a rapidly increasing range of multidisciplinaryapplications. The present paper is devoted to pattern recognition, machine learning, and the analysisof sleep stages in the detection of sleep disorders using polysomnography (PSG data, includingelectroencephalography (EEG, breathing (Flow, and electro-oculogram (EOG signals. The proposedmethod is based on the classification of selected features by a neural network system with sigmoidaland softmax transfer functions using Bayesian methods for the evaluation of the probabilities of theseparate classes. The application is devoted to the analysis of the sleep stages of 184 individualswith different diagnoses, using EEG and further PSG signals. Data analysis points to an averageincrease of the length of the Wake stage by 2.7% per 10 years and a decrease of the length of theRapid Eye Movement (REM stages by 0.8% per 10 years. The mean classification accuracy for givensets of records and single EEG and multimodal features is 88.7% ( standard deviation, STD: 2.1 and89.6% (STD:1.9, respectively. The proposed methods enable the use of adaptive learning processesfor the detection and classification of health disorders based on prior specialist experience andman–machine interaction.

  15. Computation of antenna pattern correlation and MIMO performance by means of surface current distribution and spherical wave theory

    Directory of Open Access Journals (Sweden)

    O. Klemp

    2006-01-01

    Full Text Available In order to satisfy the stringent demand for an accurate prediction of MIMO channel capacity and diversity performance in wireless communications, more effective and suitable models that account for real antenna radiation behavior have to be taken into account. One of the main challenges is the accurate modeling of antenna correlation that is directly related to the amount of channel capacity or diversity gain which might be achieved in multi element antenna configurations. Therefore spherical wave theory in electromagnetics is a well known technique to express antenna far fields by means of a compact field expansion with a reduced number of unknowns that was recently applied to derive an analytical approach in the computation of antenna pattern correlation. In this paper we present a novel and efficient computational technique to determine antenna pattern correlation based on the evaluation of the surface current distribution by means of a spherical mode expansion.

  16. Privacy transparency patterns

    NARCIS (Netherlands)

    Siljee B.I.J.

    2015-01-01

    This paper describes two privacy patterns for creating privacy transparency: the Personal Data Table pattern and the Privacy Policy Icons pattern, as well as a full overview of privacy transparency patterns. It is a first step in creating a full set of privacy design patterns, which will aid

  17. Impacts of a jet's exit flow pattern on mixing and combustion performance

    Energy Technology Data Exchange (ETDEWEB)

    Nathan, G.J.; Mi, J.; Newbold, G.J.R.; Nobes, D.S. [Turbulence, Energy and Combustion Group, School of Mechanical Engineering, The University of Adelaide, South Australia 5005 (Australia); Alwahabi, Z.T. [Turbulence, Energy and Combustion Group, Chemical Engineering, The University of Adelaide, South Australia 5005 (Australia)

    2006-09-15

    The influence of modifying a jet's exit flow pattern on both the near and far-field turbulent mixing processes and on the resulting combustion performance, is explored. This reveals that, in contradiction to some common assumptions, increasing the coherence of large-scale motions can decrease molecular mixing rates, and yet can still be beneficial in some applications. Even relatively minor changes to the exit flow pattern of a non-reacting round jet, through changes to the nozzle profile are found to propagate downstream into the far field, apparently through the underlying turbulent structure. Importantly, while a jet from a smoothly contracting nozzle is found to have higher rates of entrainment, mean spread and mean decay of the scalar field than does a long pipe jet, it has a lower rate of molecular mixing. That is, increased large-scale mixing does not necessarily result in increased fine-scale mixing. A range of devices are reviewed which enhance, or stimulate the large-scale, coherent motions in an emerging jet using acoustic, mechanical or fluidic methods. The available evidence suggests that those methods which induce instantaneously asymmetric flow structure are more effective at increasing the near-field spreading than are those which induce instantaneously axisymmetric flow structure. Only limited data are available of the effects of such near-field changes on the far-field properties. Nevertheless, the available data reveal a clear trend that this near-field flow undergoes a transition to a far-field state whose spread and decay is comparable with that of a steady jet, albeit being indelibly altered by the near-field excitation. It also suggests that 'self-exciting' devices (i.e. that are not externally forced), cause a net reduction in the total entrainment relative to the unexcited jet, due to the losses induced by the device itself. Nevertheless, the changes which they can impart to the flow, such as redistributing the turbulent

  18. Impacts of a jet's exit flow pattern on mixing and combustion performance

    Energy Technology Data Exchange (ETDEWEB)

    Nathan, G J; Mi, J; Newbold, G J.R.; Nobes, D S [Turbulence, Energy and Combustion Group, School of Mechanical Engineering, The University of Adelaide, South Australia 5005 (Australia); Alwahabi, Z T [Turbulence, Energy and Combustion Group, Chemical Engineering, The University of Adelaide, South Australia 5005 (Australia)

    2006-09-15

    The influence of modifying a jet's exit flow pattern on both the near and far-field turbulent mixing processes and on the resulting combustion performance, is explored. This reveals that, in contradiction to some common assumptions, increasing the coherence of large-scale motions can decrease molecular mixing rates, and yet can still be beneficial in some applications. Even relatively minor changes to the exit flow pattern of a non-reacting round jet, through changes to the nozzle profile are found to propagate downstream into the far field, apparently through the underlying turbulent structure. Importantly, while a jet from a smoothly contracting nozzle is found to have higher rates of entrainment, mean spread and mean decay of the scalar field than does a long pipe jet, it has a lower rate of molecular mixing. That is, increased large-scale mixing does not necessarily result in increased fine-scale mixing. A range of devices are reviewed which enhance, or stimulate the large-scale, coherent motions in an emerging jet using acoustic, mechanical or fluidic methods. The available evidence suggests that those methods which induce instantaneously asymmetric flow structure are more effective at increasing the near-field spreading than are those which induce instantaneously axisymmetric flow structure. Only limited data are available of the effects of such near-field changes on the far-field properties. Nevertheless, the available data reveal a clear trend that this near-field flow undergoes a transition to a far-field state whose spread and decay is comparable with that of a steady jet, albeit being indelibly altered by the near-field excitation. It also suggests that 'self-exciting' devices (i.e. that are not externally forced), cause a net reduction in the total entrainment relative to the unexcited jet, due to the losses induced by the device itself. Nevertheless, the changes which they can impart to the flow, such as redistributing the turbulent energy from the

  19. Control and near-field detection of surface plasmon interference patterns.

    Science.gov (United States)

    Dvořák, Petr; Neuman, Tomáš; Břínek, Lukáš; Šamořil, Tomáš; Kalousek, Radek; Dub, Petr; Varga, Peter; Šikola, Tomáš

    2013-06-12

    The tailoring of electromagnetic near-field properties is the central task in the field of nanophotonics. In addition to 2D optics for optical nanocircuits, confined and enhanced electric fields are utilized in detection and sensing, photovoltaics, spatially localized spectroscopy (nanoimaging), as well as in nanolithography and nanomanipulation. For practical purposes, it is necessary to develop easy-to-use methods for controlling the electromagnetic near-field distribution. By imaging optical near-fields using a scanning near-field optical microscope, we demonstrate that surface plasmon polaritons propagating from slits along the metal-dielectric interface form tunable interference patterns. We present a simple way how to control the resulting interference patterns both by variation of the angle between two slits and, for a fixed slit geometry, by a proper combination of laser beam polarization and inhomogeneous far-field illumination of the structure. Thus the modulation period of interference patterns has become adjustable and new variable patterns consisting of stripelike and dotlike motifs have been achieved, respectively.

  20. Polytypic pattern matching

    NARCIS (Netherlands)

    Jeuring, J.T.

    1995-01-01

    The pattern matching problem can be informally specified as follows: given a pattern and a text, find all occurrences of the pattern in the text. The pattern and the text may both be lists, or they may both be trees, or they may both be multi-dimensional arrays, etc. This paper describes a general

  1. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Directory of Open Access Journals (Sweden)

    Arindam Pal

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for 2×2 MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  2. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Directory of Open Access Journals (Sweden)

    Pal Arindam

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  3. Male pattern baldness (image)

    Science.gov (United States)

    Male pattern baldness is a sex-linked characteristic that is passed from mother to child. A man can more accurately predict his chances of developing male pattern baldness by observing his mother's father than by looking ...

  4. Male pattern baldness

    Science.gov (United States)

    Alopecia in men; Baldness - male; Hair loss in men; Androgenetic alopecia ... Male pattern baldness is related to your genes and male sex hormones. It usually follows a pattern of receding hairline and ...

  5. Caching Patterns and Implementation

    Directory of Open Access Journals (Sweden)

    Octavian Paul ROTARU

    2006-01-01

    Full Text Available Repetitious access to remote resources, usually data, constitutes a bottleneck for many software systems. Caching is a technique that can drastically improve the performance of any database application, by avoiding multiple read operations for the same data. This paper addresses the caching problems from a pattern perspective. Both Caching and caching strategies, like primed and on demand, are presented as patterns and a pattern-based flexible caching implementation is proposed.The Caching pattern provides method of expensive resources reacquisition circumvention. Primed Cache pattern is applied in situations in which the set of required resources, or at least a part of it, can be predicted, while Demand Cache pattern is applied whenever the resources set required cannot be predicted or is unfeasible to be buffered.The advantages and disadvantages of all the caching patterns presented are also discussed, and the lessons learned are applied in the implementation of the pattern-based flexible caching solution proposed.

  6. Making Pattern Mining Useful

    NARCIS (Netherlands)

    Vreeken, J.

    2009-01-01

    The discovery of patterns plays an important role in data mining. A pattern can be any type of regularity displayed in that data, such as, e.g. which items are typically sold together, which genes are mostly active for patients of a certain disease, etc, etc. Generally speaking, finding a pattern is

  7. Multi-field electron emission pattern of 2D emitter: Illustrated with graphene

    Science.gov (United States)

    Luo, Ma; Li, Zhibing

    2016-11-01

    The mechanism of laser-assisted multi-field electron emission of two-dimensional emitters is investigated theoretically. The process is basically a cold field electron emission but having more controllable components: a uniform electric field controls the emission potential barrier, a magnetic field controls the quantum states of the emitter, while an optical field controls electron populations of specified quantum states. It provides a highly orientational vacuum electron line source whose divergence angle over the beam plane is inversely proportional to square root of the emitter height. Calculations are carried out for graphene with the armchair emission edge, as a concrete example. The rate equation incorporating the optical excitation, phonon scattering, and thermal relaxation is solved in the quasi-equilibrium approximation for electron population in the bands. The far-field emission patterns, that inherit the features of the Landau bands, are obtained. It is found that the optical field generates a characteristic structure at one wing of the emission pattern.

  8. Simulated near-field mapping of ripple pattern supported metal nanoparticles arrays for SERS optimization

    Science.gov (United States)

    Arya, Mahima; Bhatnagar, Mukul; Ranjan, Mukesh; Mukherjee, Subroto; Nath, Rabinder; Mitra, Anirban

    2017-11-01

    An analytical model has been developed using a modified Yamaguchi model along with the wavelength dependent plasmon line-width correction. The model has been used to calculate the near-field response of random nanoparticles on the plane surface, elongated and spherical silver nanoparticle arrays supported on ion beam produced ripple patterned templates. The calculated near-field mapping for elongated nanoparticles arrays on the ripple patterned surface shows maximum number of hot-spots with a higher near-field enhancement (NFE) as compared to the spherical nanoparticle arrays and randomly distributed nanoparticles on the plane surface. The results from the simulations show a similar trend for the NFE when compared to the far field reflection spectra. The nature of the wavelength dependent NFE is also found to be in agreement with the observed experimental results from surface enhanced Raman spectroscopy (SERS). The calculated and the measured optical response unambiguously reveal the importance of interparticle gap and ordering, where a high intensity Raman signal is obtained for ordered elongated nanoparticles arrays case as against non-ordered and the aligned configuration of spherical nanoparticles on the rippled surface.

  9. Optical characterization of OLED emitter properties by radiation pattern analyses

    Energy Technology Data Exchange (ETDEWEB)

    Flaemmich, Michael

    2011-09-08

    Researches in both, academia and industry are investigating optical loss channels in OLED layered systems by means of optical simulation tools in order to derive promising concepts for a further enhancement of the overall device performance. Besides other factors, the prospects of success of such optimization strategies rely severely on the credibility of the optical input data. The present thesis provides a guideline to measure the active optical properties of OLED emitter materials in situ by radiation pattern analyses. Reliable and widely applicable methods are introduced to determine the internal electroluminescence spectrum, the profile of the emission zone, the dipole emitter orientation, and the internal luminescence quantum efficiency of emissive materials from the optical far field emission of OLEDs in electrical operation. The proposed characterization procedures are applied to sets of OLEDs containing both, fluorescent polymeric materials as well as phosphorescent small-molecular emitters, respectively. On the one hand, quite expected results are obtained. On the other hand, several novel and truly surprising results are found. Most importantly, this thesis contains the first report of a non-isotropic, mainly parallel emitter orientation in a phosphorescent small-molecular guest-host system (Ir(MDQ)2(acac) in a-NPD). Due to the latter result, emitter orientation based optimization of phosphorescent OLEDs seems to be within reach. Since parallel dipoles emit preferably into air, the utilization of smart emissive materials with advantageous molecular orientation is capable to boost the efficiency of phosphorescent OLEDs by 50%. Materials design, the influence of the matrix material and the substrate, as well as film deposition conditions are just a few parameters that need to be studied further in order to exploit the huge potential of the dipole emitter orientation in phosphorescent OLEDs.

  10. Vertical axis rotation (or lack thereof) of the eastern Mongolian Altay Mountains: Implications for far-field transpressional mountain building

    Science.gov (United States)

    Gregory, Laura C.; Mac Niocaill, Conall; Walker, Richard T.; Bayasgalan, Gantulga; Craig, Tim J.

    2018-06-01

    The Altay Mountains of Western Mongolia accommodate 10-20% of the current shortening of the India-Asia collision in a transpressive regime. Kinematic models of the Altay require faults to rotate anticlockwise about a vertical axis in order to accommodate compressional deformation on the major strike slip faults that cross the region. Such rotations should be detectable by palaeomagnetic data. Previous estimates from the one existing palaeomagnetic study from the Altay, on Oligocene and younger sediments from the Chuya Basin in the Siberian Altay, indicate that at least some parts of the Altay have experienced up to 39 ± 8° of anticlockwise rotation. Here, we present new palaeomagnetic results from samples collected in Cretaceous and younger sediments in the Zereg Basin along the Har-Us-Nuur fault in the eastern Altay Mountains, Mongolia. Our new palaeomagnetic results from the Zereg Basin provide reliable declinations, with palaeomagnetic directions from 10 sites that pass a fold test and include magnetic reversals. The declinations are not significantly rotated with respect to the directions expected from Cretaceous and younger virtual geomagnetic poles, suggesting that faults in the eastern Altay have not experienced a large degree of vertical axis rotation and cannot have rotated >7° in the past 5 m.y. The lack of rotation along the Har-Us-Nuur fault combined with a large amount of rotation in the northern Altay fits with a kinematic model for transpressional deformation in which faults in the Altay have rotated to an orientation that favours the development of flower structures and building of mountainous topography, while at the same time the range widens at the edges as strain is transferred to better oriented structures. Thus the Har-Us-Nuur fault is a relatively young fault in the Altay, and has not yet accommodated significant rotation.

  11. Exploiting of the Compression Methods for Reconstruction of the Antenna Far-Field Using Only Amplitude Near-Field Measurements

    Directory of Open Access Journals (Sweden)

    J. Puskely

    2010-06-01

    Full Text Available The novel approach exploits the principle of the conventional two-plane amplitude measurements for the reconstruction of the unknown electric field distribution on the antenna aperture. The method combines a global optimization with a compression method. The global optimization method (GO is used to minimize the functional, and the compression method is used to reduce the number of unknown variables. The algorithm employs the Real Coded Genetic Algorithm (RCGA as the global optimization approach. The Discrete Cosine Transform (DCT and the Discrete Wavelet Transform (DWT are applied to reduce the number of unknown variables. Pros and cons of methods are investigated and reported for the solution of the problem. In order to make the algorithm faster, exploitation of amplitudes from a single scanning plane is also discussed. First, the algorithm is used to obtain an initial estimate. Subsequently, the common Fourier iterative algorithm is used to reach global minima with sufficient accuracy. The method is examined measuring the dish antenna.

  12. Far-field interaction of focused relativistic electron beams in electron energy loss spectroscopy of nanoscopic platelets

    OpenAIRE

    Itskovsky, M. A.; Cohen, H.; Maniv, T.

    2008-01-01

    A quantum mechanical scattering theory for relativistic, highly focused electron beams near nanoscopic platelets is presented, revealing a new excitation mechanism due to the electron wave scattering from the platelet edges. Radiative electromagnetic excitations within the light cone are shown to arise, allowed by the breakdown of momentum conservation along the beam axis in the inelastic scattering process. Calculated for metallic (silver and gold) and insulating (SiO2 and MgO) nanoplatelets...

  13. Noise-Source Separation Using Internal and Far-Field Sensors for a Full-Scale Turbofan Engine

    Science.gov (United States)

    Hultgren, Lennart S.; Miles, Jeffrey H.

    2009-01-01

    Noise-source separation techniques for the extraction of the sub-dominant combustion noise from the total noise signatures obtained in static-engine tests are described. Three methods are applied to data from a static, full-scale engine test. Both 1/3-octave and narrow-band results are discussed. The results are used to assess the combustion-noise prediction capability of the Aircraft Noise Prediction Program (ANOPP). A new additional phase-angle-based discriminator for the three-signal method is also introduced.

  14. Trans-Hudsonian far-field deformation effects in the Rae foreland: An integrated geological-3D magnetic model

    Science.gov (United States)

    Percival, J. A.; Tschirhart, V.

    2017-03-01

    The intracratonic Rae cover sequence, deposited ca. 2.2-1.9 Ga, forms a useful marker for unravelling tectonic events that affected the Archean Rae Province at ca.2.0, 1.9 and 1.85 Ga. Polyphase deformation is recognized within the Rae cover rocks, including the 70 × 10 km Montresor belt, and attributed to distal effects of the ca. 1.85 Ga Trans-Hudson orogeny. In this contribution we explore the 3D geometry and structural history of the Montresor belt, previously considered to be a simple syncline lying unconformably on Archean basement. New geological, geophysical and geochronological results define a more complex history in which lower Montresor units were thrust-imbricated with basement gneisses and metamorphosed to the amphibolite facies. Mid-to upper greenschist facies upper Montresor units, exposed in an open synform, are superficially less deformed. However, using high-resolution aeromagnetic data and distinct magnetic marker units considered proxies for bedding, we constructed a set of forward models to explore the three-dimensional geometry of the belt. The re-analysis outlines a set of pre-synform structures defined by low-angle truncations of the magnetic markers. Geometric relationships indicate the presence of at least three faults at low angles to bedding, interpreted as D1 piggy-back thrusts, and bracketed by available geochronology between 1.924 and 1.87 Ga. D1 strain in the upper Montresor strata is significantly less intense than that further south in Rae cover rocks, consistent with a more distal foreland setting during the Trans-Hudson orogeny. The Montresor belt preserves a record of the Trans-Hudson tectonic style at relatively shallow crustal levels as a result of its foreland setting and structural history including a syn-orogenic extensional detachment event.

  15. Analysis of a Shock-Associated Noise Prediction Model Using Measured Jet Far-Field Noise Data

    Science.gov (United States)

    Dahl, Milo D.; Sharpe, Jacob A.

    2014-01-01

    A code for predicting supersonic jet broadband shock-associated noise was assessed using a database containing noise measurements of a jet issuing from a convergent nozzle. The jet was operated at 24 conditions covering six fully expanded Mach numbers with four total temperature ratios. To enable comparisons of the predicted shock-associated noise component spectra with data, the measured total jet noise spectra were separated into mixing noise and shock-associated noise component spectra. Comparisons between predicted and measured shock-associated noise component spectra were used to identify deficiencies in the prediction model. Proposed revisions to the model, based on a study of the overall sound pressure levels for the shock-associated noise component of the measured data, a sensitivity analysis of the model parameters with emphasis on the definition of the convection velocity parameter, and a least-squares fit of the predicted to the measured shock-associated noise component spectra, resulted in a new definition for the source strength spectrum in the model. An error analysis showed that the average error in the predicted spectra was reduced by as much as 3.5 dB for the revised model relative to the average error for the original model.

  16. Gevoeligheidsonderzoek Alarmmodel Rijn : De invloed van near-field processen op een far-field dispersie beschrijving

    NARCIS (Netherlands)

    Noppeney, R.M.

    1988-01-01

    Dispersie in rivieren wordt meestal beschouwd als een proces dat voldoet aan de één-dimensionale vergelijking van Taylor. Toepassing van het één-dimensionale Taylor-model als beschrijving voor dispersie in rivieren is formeel slechts geoorloofd op (grote) afstand vanaf een lozingspunt.

  17. Far field from near field measurements. An approach to solve the inverse problem of electromagnetic radiation via genetic algorithms

    Directory of Open Access Journals (Sweden)

    Arturo Rangel Merino

    2011-01-01

    Full Text Available En este artículo se reporta la aplicación de los Algoritmos Genéticos como método de búsqueda de una configuración de dipolos elementales que resuelven el problema inverso de radiación electromagnética. El problema inverso de radiación electromagnética aparece como una aplicación en el área de compatibilidad electromagnética para permitir estimar las radiaciones de campo lejano a partir de mediciones de campo cercano.

  18. Far field from near field measurements. An approach to solve the inverse problem of electromagnetic radiation via genetic algorithms

    OpenAIRE

    Arturo Rangel Merino; Roberto Linares y Miranda; José Luis López Bonilla

    2011-01-01

    En este artículo se reporta la aplicación de los Algoritmos Genéticos como método de búsqueda de una configuración de dipolos elementales que resuelven el problema inverso de radiación electromagnética. El problema inverso de radiación electromagnética aparece como una aplicación en el área de compatibilidad electromagnética para permitir estimar las radiaciones de campo lejano a partir de mediciones de campo cercano.

  19. Geochemical factors affecting radionuclide transport through near and far fields at a Low-Level Waste Disposal Site

    International Nuclear Information System (INIS)

    Kaplan, D.I.; Seme, R.J.; Piepkho, M.G.

    1995-03-01

    The concentration of low-level waste (LLW) contaminants in groundwater is determined by the amount of contaminant present in the solid waste, rate of release from the waste and surrounding barriers, and a number of geochemical processes including adsorption, desorption, diffusion, precipitation, and dissolution. To accurately predict radionuclide transport through the subsurface, it is essential that the important geochemical processes affecting radionuclide transport be identified and, perhaps more importantly, accurately quantified and described in a mathematically defensible manner

  20. Geological record of tsunami inundations in Pantano Morghella (south-eastern Sicily both from near and far-field sources

    Directory of Open Access Journals (Sweden)

    F. Gerardi

    2012-04-01

    Full Text Available Analysis of tsunami deposits from the Pantano Morghella area provided geological evidence for two inundations occurred along the south-eastern Ionian coast of Sicily. Pantano Morghella is a large pond characterised by a fine-grained sedimentation indicating a low-energy depositional environment. Two anomalous yellow sandy layers found at different depths indicate the occurrence of high-energy marine inundations. We studied sedimentological and paleontological features of the anomalous deposits as well as their spatial distribution observing the following properties: different facies with respect to the local stratigraphic sequence; erosive bases, rip-up clasts and broken elements testifying violent deposition mechanisms; macro and micro fauna of marine environment; relatively constant thickness throughout most of the depositional zone with thinning at the distal end; large sand sheets that extend inland. These observations, jointly with their infrequency in the sedimentary record and the age indicating a fast deposition, provided strong evidence for tsunami inundations. Correlations between anomalous layers and historical tsunamis are supported by radiocarbon and OSL dating results. The younger deposit is likely due to the 1908 near-source tsunami, whereas the flooding of the oldest event is most likely associated with a far and large source, the Crete 365 AD earthquake.

  1. Project SAFE. Update of the SFR-1 safety assessment. Phase 1. Appendix A4: Far-field

    International Nuclear Information System (INIS)

    Follin, S.; Andersson, Johan; Holmen, J.; Axelsson, C.L.

    1998-01-01

    This appendix has identified potential needs for updated hydrogeological modelling of the SFR in connection to the planned update of the performance assessment of the SFR within the framework of the SAFE-project. The objectives of such updated modelling should be to present a credible representation of the hydrogeological system, to explore effects of seals and repository extensions and to provide input to the release and transport calculations of the assessment. The last objective has led to the conclusion that an important focus of the modelling should be to determine the flow through the vaults under different conditions as this flow appear to be a very important quantity in the radionuclide release calculations. The suggested modelling should use relevant data and apply modern modelling tools and techniques, but should be geared towards the objectives. For this reasons it is suggested to apply a set of complementary and sometimes nested approaches, where each model approach is set up in order to address a specific set of questions. Answering these questions would motivate simplifications made in subsequent steps of the modelling. To the extent possible the models should be compared with existing data on flow and Baltic water breakthrough. However, in making such comparisons the accuracy of the measurements and the precision of the models need to be considered. A one-to-one match cannot be expected. It appears that careful geochemical evaluation of the site would only be necessary if more credit is placed on migration in the geosphere. If such an evaluation is considered it should be co-ordinated with the regional groundwater modelling. The issue of gas production should be reconsidered in a scenario and process analysis of SFR. However, given the strong conclusions already made it appears that gas migration in the rock will still remain as a minor issue. The major assumptions going into the analysis of the near-field in the final safety report and the deepened safety report. Assumed initial near-field conditions and considered processes and properties related to the barrier performance and radionuclide release that may have to be revised in the new analyses are identified. Topics identified by the regulatory authorities as important areas or areas that should be continuously updated when more information is available are identified, as well as general topics of importance and needs of improvements

  2. Verification and validation of predictive computer programs describing the near and far-field chemistry of radioactive waste disposal systems

    International Nuclear Information System (INIS)

    Read, D.; Broyd, T.W.

    1988-01-01

    This paper provides an introduction to CHEMVAL, an international project concerned with establishing the applicability of chemical speciation and coupled transport models to the simulation of realistic waste disposal situations. The project aims to validate computer-based models quantitatively by comparison with laboratory and field experiments. Verification of the various computer programs employed by research organisations within the European Community is ensured through close inter-laboratory collaboration. The compilation and review of thermodynamic data forms an essential aspect of this work and has led to the production of an internally consistent standard CHEMVAL database. The sensitivity of results to variation in fundamental constants is being monitored at each stage of the project and, where feasible, complementary laboratory studies are used to improve the data set. Currently, thirteen organisations from five countries are participating in CHEMVAL which forms part of the Commission of European Communities' MIRAGE 2 programme of research. (orig.)

  3. Pattern recognition & machine learning

    CERN Document Server

    Anzai, Y

    1992-01-01

    This is the first text to provide a unified and self-contained introduction to visual pattern recognition and machine learning. It is useful as a general introduction to artifical intelligence and knowledge engineering, and no previous knowledge of pattern recognition or machine learning is necessary. Basic for various pattern recognition and machine learning methods. Translated from Japanese, the book also features chapter exercises, keywords, and summaries.

  4. Learning Python design patterns

    CERN Document Server

    Zlobin, Gennadiy

    2013-01-01

    This book takes a tutorial-based and user-friendly approach to covering Python design patterns. Its concise presentation means that in a short space of time, you will get a good introduction to various design patterns.If you are an intermediate level Python user, this book is for you. Prior knowledge of Python programming is essential. Some knowledge of UML is also required to understand the UML diagrams which are used to describe some design patterns.

  5. Patterns of Peeragogy

    OpenAIRE

    Corneli, Joseph; Danoff, Charles Jeffrey; Pierce, Charlotte; Ricaurte, Paola; MacDonald, Lisa Snow

    2015-01-01

    We describe nine design patterns that we have developed in our work on the Peeragogy project, in which we aim to help design the future of learning, inside and outside of institutions, drawing on the principles of free/libre/open source software and open culture. We use these patterns to build an “emergent roadmap” for the project. Our use of design patterns has some novel features that will be relevant to others working in projects with emergent structure.

  6. Optical Pattern Recognition

    Science.gov (United States)

    Yu, Francis T. S.; Jutamulia, Suganda

    2008-10-01

    Contributors; Preface; 1. Pattern recognition with optics Francis T. S. Yu and Don A. Gregory; 2. Hybrid neural networks for nonlinear pattern recognition Taiwei Lu; 3. Wavelets, optics, and pattern recognition Yao Li and Yunglong Sheng; 4. Applications of the fractional Fourier transform to optical pattern recognition David Mendlovic, Zeev Zalesky and Haldum M. Oxaktas; 5. Optical implementation of mathematical morphology Tien-Hsin Chao; 6. Nonlinear optical correlators with improved discrimination capability for object location and recognition Leonid P. Yaroslavsky; 7. Distortion-invariant quadratic filters Gregory Gheen; 8. Composite filter synthesis as applied to pattern recognition Shizhou Yin and Guowen Lu; 9. Iterative procedures in electro-optical pattern recognition Joseph Shamir; 10. Optoelectronic hybrid system for three-dimensional object pattern recognition Guoguang Mu, Mingzhe Lu and Ying Sun; 11. Applications of photrefractive devices in optical pattern recognition Ziangyang Yang; 12. Optical pattern recognition with microlasers Eung-Gi Paek; 13. Optical properties and applications of bacteriorhodopsin Q. Wang Song and Yu-He Zhang; 14. Liquid-crystal spatial light modulators Aris Tanone and Suganda Jutamulia; 15. Representations of fully complex functions on real-time spatial light modulators Robert W. Cohn and Laurence G. Hassbrook; Index.

  7. Professional ASPNET Design Patterns

    CERN Document Server

    Millett, Scott

    2010-01-01

    Professional ASP.NET Design Patterns will show you how to implement design patterns in real ASP.NET applications by introducing you to the basic OOP skills needed to understand and interpret design patterns. A sample application used throughout the book is an enterprise level ASP.NET website with multi-tiered, SOA design techniques that can be applied to your future ASP.NET projects. Read about each design pattern in detail, including how to interpret the UML design, how to implement it in ASP.NET, its importance for ASP.NET development, and how it's integrated into the final project.

  8. Patterns - "A crime solver".

    Science.gov (United States)

    Nagasupriya, A; Dhanapal, Raghu; Reena, K; Saraswathi, Tr; Ramachandran, Cr

    2011-01-01

    This study is intended to analyze the predominant pattern of lip and finger prints in males and females and to correlate lip print and finger print for gender identity. The study sample comprised of 200 students of Vishnu Dental College, Bhimavaram, Andhra Pradesh, 100 males and 100 females aged between 18 to 27 years. Brown/pink colored lip stick was applied on the lips and the subject was asked to spread it uniformly over the lips. Lip prints were traced in the normal rest position of the lips with the help of cellophane tape. The imprint of the left thumb was taken on a white chart sheet and visualized using magnifying lens. While three main types of finger prints are identified, the classification of lip prints is simplified into branched, reticular, and vertical types. Association between lip prints and finger prints was statistically tested using Chi-square test. This study showed that lip and finger patterns did not reveal statistically significant results within the gender. The correlation between lip and finger patterns for gender identification, was statistically significant. In males, branched type of lip pattern associated with arch, loop, and whorl type of finger pattern was most significant. In females, vertical lip pattern associated with arch finger pattern and reticular lip pattern associated with whorl finger patterns were most significant. We conclude that a correlative study between the lip print and finger print will be very useful in forensic science for gender identification.

  9. Patterns in natural systems

    NARCIS (Netherlands)

    Sewalt, L.

    2016-01-01

    In the thesis, `Patterns in natural systems’ the formation and evolution of patterns as solutions of several partial differential systems are studied. These mathematical systems model three different biological and ecological processes. First, the way that plankton concentrates in the water column,

  10. Discovery: Pile Patterns

    Science.gov (United States)

    de Mestre, Neville

    2017-01-01

    Earlier "Discovery" articles (de Mestre, 1999, 2003, 2006, 2010, 2011) considered patterns from many mathematical situations. This article presents a group of patterns used in 19th century mathematical textbooks. In the days of earlier warfare, cannon balls were stacked in various arrangements depending on the shape of the pile base…

  11. Patterns in Software Development

    DEFF Research Database (Denmark)

    Corry, Aino Vonge

    the university and I entered a project to industry within Center for Object Technology (COT). I focused on promoting the pattern concept to the Danish software industry in order to help them take advantage of the benefits of applying patterns in system development. In the obligatory stay abroad, I chose to visit...

  12. Complex Systems and Patterns

    NARCIS (Netherlands)

    Pieters, C.P.

    2008-01-01

    Although the term 'pattern' is often used in science, it is an elusive term and can have different dialectic meanings in various disciplines. Yet, the 'feel' for this term is fairly consistent; it usually requires little explanation to understand what a pattern is, and therefore it usually tends to

  13. Patterns of Academic Procrastination.

    Science.gov (United States)

    Day, Victor; Mensink, David; O'Sullivan, Michael

    2000-01-01

    Uses the Academic Procrastination Questionnaire to measure procrastination and six possible patterns underlying it among undergraduate students. Finds that the most common patterns for clients involved Evaluation Anxiety or being Discouraged/Depressed, or Dependent. Supports individualized assessment and solutions for academic procrastination. (SC)

  14. Engaging with Islamic Patterns

    Science.gov (United States)

    Sugarman, Ian

    2012-01-01

    Islamic patterns were a regular feature in mathematics classrooms, and probably still feature in many wall displays. However, as part of the learning process, these ancient designs appear to have lost any significant contemporary appeal. Here, the power of software is engaged to bring the construction of Islamic type patterns up to date. Forget…

  15. Is It a Pattern?

    Science.gov (United States)

    McGarvey, Lynn M.

    2013-01-01

    This article describes how in early mathematics learning, young children are often asked to recognize and describe visual patterns in their environment--perhaps on their clothing, a toy, or the carpet; around a picture frame; or in the playground equipment. Exploring patterns in the early years is seen as an important introduction to algebraic…

  16. Patterns of Knowledge Construction

    Science.gov (United States)

    Chang, Bo

    2018-01-01

    The purpose of this study was to identify knowledge construction patterns in a local learning community. Observation, documents, and semistructured interviews were employed to collect data. Twenty learners were interviewed. Data were analyzed inductively using the constant comparative method. Five major patterns--radiation, circulation,…

  17. Statistical Pattern Recognition

    CERN Document Server

    Webb, Andrew R

    2011-01-01

    Statistical pattern recognition relates to the use of statistical techniques for analysing data measurements in order to extract information and make justified decisions.  It is a very active area of study and research, which has seen many advances in recent years. Applications such as data mining, web searching, multimedia data retrieval, face recognition, and cursive handwriting recognition, all require robust and efficient pattern recognition techniques. This third edition provides an introduction to statistical pattern theory and techniques, with material drawn from a wide range of fields,

  18. Parallel Algorithms and Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Robey, Robert W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-16

    This is a powerpoint presentation on parallel algorithms and patterns. A parallel algorithm is a well-defined, step-by-step computational procedure that emphasizes concurrency to solve a problem. Examples of problems include: Sorting, searching, optimization, matrix operations. A parallel pattern is a computational step in a sequence of independent, potentially concurrent operations that occurs in diverse scenarios with some frequency. Examples are: Reductions, prefix scans, ghost cell updates. We only touch on parallel patterns in this presentation. It really deserves its own detailed discussion which Gabe Rockefeller would like to develop.

  19. Antenna Pattern Range (APR)

    Data.gov (United States)

    Federal Laboratory Consortium — TheAntenna Pattern Range (APR)features a non-metallic arch with a trolley to move the transmit antenna from the horizon to zenith. At the center of the ground plane,...

  20. Four integration patterns

    DEFF Research Database (Denmark)

    Bygstad, Bendik; Nielsen, Peter Axel; Munkvold, Bjørn Erik

    2010-01-01

    This paper aims to contribute to a theory of integration within the field of IS project management. Integration is a key IS project management issue when new systems are developed and implemented into an increasingly integrated information infrastructure in corporate and governmental organizations....... Expanding the perspective of traditional project management research, we draw extensively on central insights from IS research. Building on socio-technical IS research and Software Engineering research we suggest four generic patterns of integration: Big Bang, Stakeholder Integration, Technical Integration...... and Socio-Technical Integration. We analyze and describe the advantages and disadvantages of each pattern. The four patterns are ideal types. To explore the forces and challenges in these patterns three longitudinal case studies were conducted. In particular we investigate the management challenges for each...

  1. Life History Patterns

    DEFF Research Database (Denmark)

    Jones, Owen

    2016-01-01

    of these patterns and highlights the need to consider senescence from a broad taxonomic scope to truly understand the evolution of aging. Keywords: Aging; Demography; Evolution; Fertility; Gompertz; Life span; Mortality; Ontogenescence; Reproduction; Reproductive senescence; Senescence; Survivorship...

  2. Dietary Patterns in Childhood

    DEFF Research Database (Denmark)

    Andersen, Louise Beltoft Borup

    A healthy diet is essential for healthy growth and development during childhood and may prevent obesity, diabetes, and cardiovascular diseases throughout life. Traditionally, diet has been investigated as single nutrients. However, people do not eat one single nutrient and they do not even eat one...... single food. People consume meals and these meals vary during a day, over a year and during a life time. To comprehend some of this complexity it could be advantageous to investigate dietary patterns representing the whole diet as patterns might be better markers of growth and health than single...... childhood. These associations might contribute to the identification of families, who would benefit from guidance to help them establish healthy dietary patterns for their infants. Finding tracking for some infants and changes in adherence to dietary patterns for others as well as the association between...

  3. Caregiving and travel patterns.

    Science.gov (United States)

    2013-06-01

    This study explored the impact of caregiving for older adults on mobility and travel : patterns. Specifically, the focus was on how caregivers managed trips on behalf of : another who receives care. Caregiving is becoming increasingly common as the :...

  4. Windowed fringe pattern analyis

    CERN Document Server

    Kemao, Qian

    2013-01-01

    This book provides solutions to the challenges involved in fringe pattern analysis, covering techniques for full-field, noncontact, and high-sensitivity measurement. The primary goal of fringe pattern analysis is to extract the hidden phase distributions that generally relate to the physical quantities being measured. Both theoretical analysis and algorithm development are covered to facilitate the work of researchers and engineers. The information presented is also appropriate as a specialized subject for students of optical and computer engineering.

  5. Hyponymy Patterns in Romanian

    Directory of Open Access Journals (Sweden)

    Verginica Barbu Mititelu

    2011-10-01

    Full Text Available Hyponymy is a lexical-semantic relation that has been studied in Romanian linguistics only occasionally and almost exclusively in connection to other relations. However, for computational engineers it offers a very effective way of organizing the lexical material useful in many applications involving Natural Language Processing. In this paper we present two methods of identifying Romanian hyponymy patterns, their results and evaluation; we also envisage the applicability of these patterns and future work

  6. Female pattern hair loss

    Directory of Open Access Journals (Sweden)

    İdil Ünal

    2014-06-01

    Full Text Available Female androgenetic alopecia is the commonest cause of hair loss in women. It is characterized by a diffuse reduction in hair density over the crown and frontal scalp with retention of the frontal hairline and a characteristic pattern distribution in genetically predisposed women. Because of the uncertain relationship with the androgens Female Pattern Hair Loss (FPHL is the most preferred definition of the condition. This review has been focused on the clinical features, diagnosis and treatment alternatives of FPHL.

  7. Patterned Colloidal Photonic Crystals.

    Science.gov (United States)

    Hou, Jue; Li, Mingzhu; Song, Yanlin

    2018-03-01

    Colloidal photonic crystals (PCs) have been well developed because they are easy to prepare, cost-effective, and versatile with regards to modification and functionalization. Patterned colloidal PCs contribute a novel approach to constructing high-performance PC devices with unique structures and specific functions. In this review, an overview of the strategies for fabricating patterned colloidal PCs, including patterned substrate-induced assembly, inkjet printing, and selective immobilization and modification, is presented. The advantages of patterned PC devices are also discussed in detail, for example, improved detection sensitivity and response speed of the sensors, control over the flow direction and wicking rate of microfluidic channels, recognition of cross-reactive molecules through an array-patterned microchip, fabrication of display devices with tunable patterns, well-arranged RGB units, and wide viewing-angles, and the ability to construct anti-counterfeiting devices with different security strategies. Finally, the perspective of future developments and challenges is presented. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Fuel pattern recognition device

    International Nuclear Information System (INIS)

    Sato, Tomomi.

    1995-01-01

    The device of the present invention monitors normal fuel exchange upon fuel exchanging operation carried out in a reactor of a nuclear power plant. Namely, a fuel exchanger is movably disposed to the upper portion of the reactor and exchanges fuels. An exclusive computer receives operation signals of the fuel exchanger during operation as inputs, and outputs reactor core fuel pattern information signals to a fuel arrangement diagnosis device. An underwater television camera outputs image signals of a fuel pattern in the reactor core to an image processing device. If there is any change in the image signals for the fuel pattern as a result of the fuel exchange operation of the fuel exchanger, the image processing device outputs the change as image signals to the fuel pattern diagnosis device. The fuel pattern diagnosis device compares the pattern information signals from the exclusive computer with the image signals from the image processing device, to diagnose the result of the fuel exchange operation performed by the fuel exchanger and inform the diagnosis by means of an image display. (I.S.)

  9. Large static tuning of narrow-beam terahertz plasmonic lasers operating at 78K

    Directory of Open Access Journals (Sweden)

    Chongzhao Wu

    2017-02-01

    Full Text Available A new tuning mechanism is demonstrated for single-mode metal-clad plasmonic lasers, in which the refractive-index of the laser’s surrounding medium affects the resonant-cavity mode in the same vein as the refractive-index of gain medium inside the cavity. Reversible, continuous, and mode-hop-free tuning of ∼57 GHz is realized for single-mode narrow-beam terahertz plasmonic quantum-cascade lasers (QCLs, which is demonstrated at a much more practical temperature of 78 K. The tuning is based on post-process deposition/etching of a dielectric (silicon-dioxide on a QCL chip that has already been soldered and wire-bonded onto a copper mount. This is a considerably larger tuning range compared to previously reported results for terahertz QCLs with directional far-field radiation patterns. The key enabling mechanism for tuning is a recently developed antenna-feedback scheme for plasmonic lasers, which leads to the generation of hybrid surface-plasmon-polaritons propagating outside the cavity of the laser with a large spatial extent. The effect of dielectric deposition on QCL’s characteristics is investigated in detail including that on maximum operating temperature, peak output power, and far-field radiation patterns. Single-lobed beam with low divergence (<7° is maintained through the tuning range. The antenna-feedback scheme is ideally suited for modulation of plasmonic lasers and their sensing applications due to the sensitive dependence of spectral and radiative properties of the laser on its surrounding medium.

  10. Pattern graph rewrite systems

    Directory of Open Access Journals (Sweden)

    Aleks Kissinger

    2014-03-01

    Full Text Available String diagrams are a powerful tool for reasoning about physical processes, logic circuits, tensor networks, and many other compositional structures. Dixon, Duncan and Kissinger introduced string graphs, which are a combinatoric representations of string diagrams, amenable to automated reasoning about diagrammatic theories via graph rewrite systems. In this extended abstract, we show how the power of such rewrite systems can be greatly extended by introducing pattern graphs, which provide a means of expressing infinite families of rewrite rules where certain marked subgraphs, called !-boxes ("bang boxes", on both sides of a rule can be copied any number of times or removed. After reviewing the string graph formalism, we show how string graphs can be extended to pattern graphs and how pattern graphs and pattern rewrite rules can be instantiated to concrete string graphs and rewrite rules. We then provide examples demonstrating the expressive power of pattern graphs and how they can be applied to study interacting algebraic structures that are central to categorical quantum mechanics.

  11. G ∘ F Patterns

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    The book of design patterns known as Gang of Four has been a kind of Bible for all the developers of my generation. Its main pro has been giving us a common vocabulary: when a programmer says “here I used a strategy pattern” all colleagues know of what he is speaking about. Nevertheless the biggest issue with this is that almost all patterns listed in that book, especially the behavioural ones, are a only workaround for a missing abstraction: higher order functions. The introduction of lambda expressions in Java 8 finally allows all Java developers to remove this no longer necessary and cumbersome object oriented infrastructure from their code. The purpose of this talk is showing, through a series of live coding examples, how the most common GoF patterns can be rethought and reimplemented in a simpler and more concise functional way leveraging Java 8 lambdas.

  12. Settlement patterns and sustainability

    DEFF Research Database (Denmark)

    Hendriksen, Kåre

    This paper discusses settlement patterns and sustainability. Generally urbanization is recognised as an inevitable development driven by job opportunities, better service supply, education, and health services, and it is argued that this is the main driver for centralisation. Research based...... on economic and demographic studies and a large series of interviews problematize this. In Greenland the historical correlation between settlement pattern and livelihood has been decoupled, so that distributions of jobs and potential earnings to a growing extend is a consequence of political and...

  13. Patterns of data modeling

    CERN Document Server

    Blaha, Michael

    2010-01-01

    Best-selling author and database expert with more than 25 years of experience modeling application and enterprise data, Dr. Michael Blaha provides tried and tested data model patterns, to help readers avoid common modeling mistakes and unnecessary frustration on their way to building effective data models. Unlike the typical methodology book, "Patterns of Data Modeling" provides advanced techniques for those who have mastered the basics. Recognizing that database representation sets the path for software, determines its flexibility, affects its quality, and influences whether it succ

  14. Workflow User Interfaces Patterns

    Directory of Open Access Journals (Sweden)

    Jean Vanderdonckt

    2012-03-01

    Full Text Available Este trabajo presenta una colección de patrones de diseño de interfaces de usuario para sistemas de información para el flujo de trabajo; la colección incluye cuarenta y tres patrones clasificados en siete categorías identificados a partir de la lógica del ciclo de vida de la tarea sobre la base de la oferta y la asignación de tareas a los responsables de realizarlas (i. e. recursos humanos durante el flujo de trabajo. Cada patrón de la interfaz de usuario de flujo de trabajo (WUIP, por sus siglas en inglés se caracteriza por las propiedades expresadas en el lenguaje PLML para expresar patrones y complementado por otros atributos y modelos que se adjuntan a dicho modelo: la interfaz de usuario abstracta y el modelo de tareas correspondiente. Estos modelos se especifican en un lenguaje de descripción de interfaces de usuario. Todos los WUIPs se almacenan en una biblioteca y se pueden recuperar a través de un editor de flujo de trabajo que vincula a cada patrón de asignación de trabajo a su WUIP correspondiente.A collection of user interface design patterns for workflow information systems is presented that contains forty three resource patterns classified in seven categories. These categories and their corresponding patterns have been logically identified from the task life cycle based on offering and allocation operations. Each Workflow User Interface Pattern (WUIP is characterized by properties expressed in the PLML markup language for expressing patterns and augmented by additional attributes and models attached to the pattern: the abstract user interface and the corresponding task model. These models are specified in a User Interface Description Language. All WUIPs are stored in a library and can be retrieved within a workflow editor that links each workflow pattern to its corresponding WUIP, thus giving rise to a user interface for each workflow pattern.

  15. Exploring pedestrian movement patterns

    NARCIS (Netherlands)

    Orellana, D.A.

    2012-01-01

    The main objective of this thesis is to develop an approach for exploring, analysing and interpreting movement patterns of pedestrians interacting with the environment. This objective is broken down in sub-objectives related to four research questions. A case study of the movement of visitors in a

  16. Storyboards for Meaningful Patterns

    Science.gov (United States)

    Dubon, Lucille P.; Shafer, Kathryn G.

    2010-01-01

    The initial focus of this kindergarten-level action research project was on identifying which students could create a pattern. The focus then shifted to helping all students successfully achieve this goal. The intervention uses a storyboard where students select colored cubes to represent objects and then snap the cubes together as indicated on…

  17. Patterns in chaos

    International Nuclear Information System (INIS)

    Chirikov, B.V.

    1990-01-01

    Classification of chaotic patterns in classical Hamiltonian systems is given as a series of levels with increasing disorder. Hamiltonian dynamics is presented, including the renormalization chaos, based upon the fairly simple resonant theory. First estimates for the critical structure and related statistical anomalies in arbitrary dimensions are discussed. 49 refs

  18. Motor Patterns in Walking.

    Science.gov (United States)

    Lacquaniti, F.; Grasso, R.; Zago, M.

    1999-08-01

    Despite the fact that locomotion may differ widely in mammals, common principles of kinematic control are at work. These reflect common mechanical and neural constraints. The former are related to the need to maintain balance and to limit energy expenditure. The latter are related to the organization of the central pattern-generating networks.

  19. Painting Patterns with Pixels.

    Science.gov (United States)

    Yoerg, Kim

    2002-01-01

    Describes an art unit for middle school students where they created their own original pattern through the use of "ClarisWorks Paint." Discusses the procedure for the project and the evaluation used at the end of the unit. Emphasizes the importance of learning about computers. (CMK)

  20. Organization patterns responsibilities

    International Nuclear Information System (INIS)

    Beuerle, H.J.

    1975-01-01

    To guarantee safety and safe operation of a nuclear power station the technical facilities must be supplemented by suitable administrative measures. Thus, the organization pattern of the nuclear power station or of the nuclear power station undertaking will also exert a corresponding influence. (orig./TK) [de

  1. Structural patterns in nature

    DEFF Research Database (Denmark)

    Wester, Ture

    2003-01-01

    be an inspiration to structural morphologists and other dealing with the shaping of structures for buildings and other objects. Often the patterns appear in "dual" materializations, which indicate two radically different structural types of action. Randomness as a generator for optimal and basic structural action...

  2. Structural patterns in nature

    DEFF Research Database (Denmark)

    Wester, Ture

    2004-01-01

    be an inspiration to structural morphologists and other dealing with the shaping of structures for buildings and other objects. Often the patterns appear in "dual" materializations, which indicate two radically different structural types of action. Randomness as a generator for optimal and basic structural action...

  3. Spider Web Pattern

    Science.gov (United States)

    2006-01-01

    A delicate pattern, like that of a spider web, appears on top of the Mars residual polar cap, after the seasonal carbon-dioxide ice slab has disappeared. Next spring, these will likely mark the sites of vents when the carbon-dioxide ice cap returns. This Mars Global Surveyor, Mars Orbiter Camera image is about 3-kilometers wide (2-miles).

  4. Multivariate pattern dependence.

    Directory of Open Access Journals (Sweden)

    Stefano Anzellotti

    2017-11-01

    Full Text Available When we perform a cognitive task, multiple brain regions are engaged. Understanding how these regions interact is a fundamental step to uncover the neural bases of behavior. Most research on the interactions between brain regions has focused on the univariate responses in the regions. However, fine grained patterns of response encode important information, as shown by multivariate pattern analysis. In the present article, we introduce and apply multivariate pattern dependence (MVPD: a technique to study the statistical dependence between brain regions in humans in terms of the multivariate relations between their patterns of responses. MVPD characterizes the responses in each brain region as trajectories in region-specific multidimensional spaces, and models the multivariate relationship between these trajectories. We applied MVPD to the posterior superior temporal sulcus (pSTS and to the fusiform face area (FFA, using a searchlight approach to reveal interactions between these seed regions and the rest of the brain. Across two different experiments, MVPD identified significant statistical dependence not detected by standard functional connectivity. Additionally, MVPD outperformed univariate connectivity in its ability to explain independent variance in the responses of individual voxels. In the end, MVPD uncovered different connectivity profiles associated with different representational subspaces of FFA: the first principal component of FFA shows differential connectivity with occipital and parietal regions implicated in the processing of low-level properties of faces, while the second and third components show differential connectivity with anterior temporal regions implicated in the processing of invariant representations of face identity.

  5. Wind-Induced Air-Flow Patterns in an Urban Setting: Observations and Numerical Modeling

    Science.gov (United States)

    Sattar, Ahmed M. A.; Elhakeem, Mohamed; Gerges, Bishoy N.; Gharabaghi, Bahram; Gultepe, Ismail

    2018-04-01

    City planning can have a significant effect on wind flow velocity patterns and thus natural ventilation. Buildings with different heights are roughness elements that can affect the near- and far-field wind flow velocity. This paper aims at investigating the impact of an increase in building height on the nearby velocity fields. A prototype urban setting of buildings with two different heights (25 and 62.5 cm) is built up and placed in a wind tunnel. Wind flow velocity around the buildings is mapped at different heights. Wind tunnel measurements are used to validate a 3D-numerical Reynolds averaged Naviers-Stokes model. The validated model is further used to calculate the wind flow velocity patterns for cases with different building heights. It was found that increasing the height of some buildings in an urban setting can lead to the formation of large horseshoe vortices and eddies around building corners. A separation area is formed at the leeward side of the building, and the recirculation of air behind the building leads to the formation of slow rotation vortices. The opposite effect is observed in the wake (cavity) region of the buildings, where both the cavity length and width are significantly reduced, and this resulted in a pronounced increase in the wind flow velocity. A significant increase in the wind flow velocity in the wake region of tall buildings with a value of up to 30% is observed. The spatially averaged velocities around short buildings also increased by 25% compared to those around buildings with different heights. The increase in the height of some buildings is found to have a positive effect on the wind ventilation at the pedestrian level.

  6. Patterns and Intelligent Systems

    International Nuclear Information System (INIS)

    Cordes, Gail A.

    2003-01-01

    The recognition and analysis of evolving patterns provides a unifying concept for studying and implementing intelligent information processing for open feedback control systems within the nuclear industry. Control is considered as influence of a large system to achieve the goals of the human (who might or might not be part of an open feedback loop) and is not limited to operation of a component within a nuclear power plant. The intelligent control system includes open logic and can automatically react to new data in an unprogrammed way. This application of evolving patterns integrates current research developments in human cognition and scientific semiotics with traditional feedback control. A preliminary implementation of such a system using existing computational techniques is postulated, and tools that are lacking at this time are identified. Proof-of-concept applications for the nuclear industry are referenced

  7. Fundamentals of thinking, patterns

    Science.gov (United States)

    Gafurov, O. M.; Gafurov, D. O.; Syryamkin, V. I.

    2018-05-01

    The authors analyze the fundamentals of thinking and propose to consider a model of the brain based on the presence of magnetic properties of gliacytes (Schwann cells) because of their oxygen saturation (oxygen has paramagnetic properties). The authors also propose to take into account the motion of electrical discharges through synapses causing electric and magnetic fields as well as additional effects such as paramagnetic resonance, which allows combining multisensory object-related information located in different parts of the brain. Therefore, the events of the surrounding world are reflected and remembered in the cortex columns, thus, creating isolated subnets with altered magnetic properties (patterns) and subsequently participate in recognition of objects, form a memory, and so on. The possibilities for the pattern-based thinking are based on the practical experience of applying methods and technologies of artificial neural networks in the form of a neuroemulator and neuromorphic computing devices.

  8. Pattern formation during electropolishing

    International Nuclear Information System (INIS)

    Yuzhakov, V.V.; Chang, H.; Miller, A.E.

    1997-01-01

    Using atomic force microscopy, we find that the surface morphology of a dissolving aluminum anode in a commercial electropolishing electrolyte can exhibit both highly regular and randomly packed stripe and hexagonal patterns with amplitudes of about 5 nm and wavelengths of 100 nm. The driving instability of this pattern formation phenomenon is proposed to be the preferential adsorption of polar or polarizable organic molecules on surface ridges where the contorted double layer produces a higher electric potential gradient. The enhanced relative coverage shields the anode and induces a smaller dissolution rate at the ridges. The instability is balanced by surface diffusion of the adsorbate to yield a length scale of 4π(D s /k d ) 1/2 , where D s is the surface diffusivity and k d is the desorption coefficient of the adsorbate, which correlates well with the measured wavelength. A long-wavelength expansion of the double-layer field yields an interface evolution equation that reproduces all of the observed patterns. In particular, bifurcation analysis and numerical simulation yield a single voltage-dependent dimensionless parameter ξ that measures a balance between smoothing of adsorbate concentration by electric-field-dependent surface diffusion and fluctuation due to interfacial curvature and stretching. Randomly oriented stripes are favored at large ξ (low voltage), while random hills dominate at small ξ (high voltage) with perfectly periodic stripes and hexagonal hill patterns within a small window near ξ=1. These predictions are in qualitative and quantitative agreement with our measurements. copyright 1997 The American Physical Society

  9. Shells and Patterns

    Science.gov (United States)

    Sutley, Jane

    2009-01-01

    "Shells and Patterns" was a project the author felt would easily put smiles on the faces of her fifth-graders, and teach them about unity and the use of watercolor pencils as well. It was thrilling to see the excitement in her students as they made their line drawings of shells come to life. For the most part, they quickly got the hang of…

  10. Pattern Driven Stress Localization

    Science.gov (United States)

    Croll, Andrew; Crosby, Alfred

    2010-03-01

    The self-assembly of patterns from isotropic initial states is a major driver of modern soft-matter research. This avenue of study is directed by the desire to understand the complex physics of the varied structures found in Nature, and by technological interest in functional materials that may be derived through biomimicry. In this work we show how a simple striped phase can respond with significant complexity to an appropriately chosen perturbation. In particular, we show how a buckled elastic plate transitions into a state of stress localization using a simple, self-assembled variation in surface topography. The collection of topographic boundaries act in concert to change the state from isotropic sinusoidal wrinkles, to sharp folds or creases separated by relatively flat regions. By varying the size of the imposed topographic pattern or the wavelength of the wrinkles, we construct a state diagram of the system. The localized state has implications for both biological systems, and for the control of non-linear pattern formation.

  11. Gardosian Patterns in Tribology

    Science.gov (United States)

    DellaCorte, Christopher

    2004-01-01

    The following paper is a memorial retrospective on selected research of Dr. Michael N. Gardos. Dr. Gardos spent his professional career engaged in tribological research which often extended the scientific boundaries of the field. Several of the concepts he put forth into the tribology community were initially met with grave skepticism but over time his views have been largely embraced but not widely acknowledged. His approach to new research topics was often characterized by these qualities: 1) pioneering points of view, 2) the use of the model experiment, and 3) the presence of multiple research agendas for each single experiment. I have chosen to name his research approach as "Gardosian Patterns" in honor of his contributions to Tribology. Three specific examples of these patterns will be reviewed. One is the concept of atomic level tailoring of materials to control macroscopic properties. A second is the use of a model ball polishing experiment to identify high fracture toughness ceramics for use in rolling element bearings. A third Gardosian Pattern example is his pioneering work with the tribology of diamond and diamond films in which he proposed controlling friction via surface bond tailoring. In these examples, Gardos utilized conventional research tools in unconventional ways and, at times, even developed new tools which have become part of the mainstream. His remarkable career has left a positive and lasting mark on Tribology.

  12. Pattern Recognition Control Design

    Science.gov (United States)

    Gambone, Elisabeth A.

    2018-01-01

    Spacecraft control algorithms must know the expected vehicle response to any command to the available control effectors, such as reaction thrusters or torque devices. Spacecraft control system design approaches have traditionally relied on the estimated vehicle mass properties to determine the desired force and moment, as well as knowledge of the effector performance to efficiently control the spacecraft. A pattern recognition approach was used to investigate the relationship between the control effector commands and spacecraft responses. Instead of supplying the approximated vehicle properties and the thruster performance characteristics, a database of information relating the thruster ring commands and the desired vehicle response was used for closed-loop control. A Monte Carlo simulation data set of the spacecraft dynamic response to effector commands was analyzed to establish the influence a command has on the behavior of the spacecraft. A tool developed at NASA Johnson Space Center to analyze flight dynamics Monte Carlo data sets through pattern recognition methods was used to perform this analysis. Once a comprehensive data set relating spacecraft responses with commands was established, it was used in place of traditional control methods and gains set. This pattern recognition approach was compared with traditional control algorithms to determine the potential benefits and uses.

  13. Principal oscillation patterns

    International Nuclear Information System (INIS)

    Storch, H. von; Buerger, G.; Storch, J.S. von

    1993-01-01

    The Principal Oscillation Pattern (POP) analysis is a technique which is used to simultaneously infer the characteristic patterns and time scales of a vector time series. The POPs may be seen as the normal modes of a linearized system whose system matrix is estimated from data. The concept of POP analysis is reviewed. Examples are used to illustrate the potential of the POP technique. The best defined POPs of tropospheric day-to-day variability coincide with the most unstable modes derived from linearized theory. POPs can be derived even from a space-time subset of data. POPs are successful in identifying two independent modes with similar time scales in the same data set. The POP method can also produce forecasts which may potentially be used as a reference for other forecast models. The conventional POP analysis technique has been generalized in various ways. In the cyclostationary POP analysis, the estimated system matrix is allowed to vary deterministically with an externally forced cycle. In the complex POP analysis not only the state of the system but also its ''momentum'' is modeled. Associated correlation patterns are a useful tool to describe the appearance of a signal previously identified by a POP analysis in other parameters. (orig.)

  14. Female pattern hair loss.

    Science.gov (United States)

    Herskovitz, Ingrid; Tosti, Antonella

    2013-10-01

    Female pattern hair loss (FPHL) also known as female androgenetic alopecia is a common condition afflicting millions of women that can be cosmetically disrupting. Prompt diagnosis and treatment are essential for obtaining optimal outcome. This review addresses the clinical presentation of female pattern hair loss, its differential diagnosis and treatment modalities. A) Diffuse thinning of the crown region with preservation of the frontal hairline (Ludwig's type) B) The "Christmas tree pattern" where the thinning is wider in the frontal scalp giving the alopecic area a triangular shaped figure resembling a christmas tree. C) Thinning associated with bitemporal recession (Hamilton type). Generally, FPHL is not associated with elevated androgens. Less commonly females with FPHL may have other skin or general signs of hyperandrogenism such as hirsutism, acne, irregular menses, infertility, galactorrhea and insulin resistance. The most common endocrinological abnormality associated with FPHL is polycystic ovarian syndrome (PCOS). The most important diseases to consider in the differential diagnosis of FPHL include Chronic Telogen Effluvium (CTE), Permanent Alopecia after Chemotherapy (PAC), Alopecia Areata Incognito (AAI) and Frontal Fibrosing Alopecia (FFA). This review describes criteria for distinguishing these conditions from FPHL. The only approved treatment for FPHL, which is 2% topical Minoxidil, should be applied at the dosage of 1ml twice day for a minimum period of 12 months. This review will discuss off-label alternative modalities of treatment including 5-alfa reductase inhibitors, antiandrogens, estrogens, prostaglandin analogs, lasers, light treatments and hair transplantation.

  15. Surface-Emitting Distributed Feedback Terahertz Quantum-Cascade Lasers in Metal-Metal Waveguides

    Science.gov (United States)

    Kumar, Sushil; Williams, Benjamin S.; Qin, Qi; Lee, Alan W. M.; Hu, Qing; Reno, John L.

    2007-01-01

    Single-mode surface-emitting distributed feedback terahertz quantumcascade lasers operating around 2.9 THz are developed in metal-metal waveguides. A combination of techniques including precise control of phase of reflection at the facets, and u e of metal on the sidewalls to eliminate higher-order lateral modes allow robust single-mode operation over a range of approximately 0.35 THz. Single-lobed far-field radiation pattern is obtained using a pi phase-shift in center of the second-order Bragg grating. A grating device operating at 2.93 THz lased up to 149 K in pulsed mode and a temperature tuning of 19 .7 GHz was observed from 5 K to 147 K. The same device lased up to 78 K in continuous-wave (cw) mode emitting more than 6 m W of cw power at 5 K. ln general, maximum temperature of pulsed operation for grating devices was within a few Kelvin of that of multi-mode Fabry-Perot ridge lasers

  16. Pig design patterns

    CERN Document Server

    Pasupuleti, Pradeep

    2014-01-01

    Pig makes Hadoop programming simple, intuitive, and fun to work with. It removes the complexity from Map Reduce programming by giving the programmer immense power through its flexibility. What used to be extremely lengthy and intricate code written in other high level languages can now be written in almost one tenth of the size using its easy to understand constructs. Pig has proven to be the easiest way to learn how to program Hadoop clusters, as evidenced by its widespread adoption. This comprehensive guide enables readers to readily use design patterns to simplify the creation of complex da

  17. Subsidiary Linkage Patterns

    DEFF Research Database (Denmark)

    Andersson, Ulf; Perri, Alessandra; Nell, Phillip C.

    2012-01-01

    channels for spillovers to competitors. We find a curvilinear relationship between the extent of competitive pressure and the quality of a subsidiary's set of local linkages. Furthermore, the extent to which a subsidiary possesses capabilities moderates this relationship: Very capable subsidiaries...... in strongly competitive environments tend to shy away from high quality linkages. We discuss our findings in light of the literature on spillovers and inter-organizational linkages.......This paper investigates the pattern of subsidiaries' local vertical linkages under varying levels of competition and subsidiary capabilities. Contrary to most previous literature, we explicitly account for the double role of such linkages as conduits of learning prospects as well as potential...

  18. JavaScript Patterns

    CERN Document Server

    Stefanov, Stoyan

    2010-01-01

    What's the best approach for developing an application with JavaScript? This book helps you answer that question with numerous JavaScript coding patterns and best practices. If you're an experienced developer looking to solve problems related to objects, functions, inheritance, and other language-specific categories, the abstractions and code templates in this guide are ideal -- whether you're writing a client-side, server-side, or desktop application with JavaScript. Written by JavaScript expert Stoyan Stefanov -- Senior Yahoo! Technical and architect of YSlow 2.0, the web page performance

  19. Patterns of Internationalization

    DEFF Research Database (Denmark)

    Prockl, Günter; Kotzab, Herbert; Kinra, Aseem

    2013-01-01

    sales office networks and the overall extent of market presence. For this the fundamental sales networks of the companies were considered as a key indicator, and the port networks of the 20 largest container-shipping companies in the world (by TEU capacity) were analyzed. Findings - The resulting data...... that is based e.g. on the development pattern of single companies and that may also take more the dynamic aspects and comparisons into account. Practical implications - Preceeding work provides insights that are directed towards the port networks and thus toward the more back office oriented resource...

  20. Break the Pattern!

    DEFF Research Database (Denmark)

    Hasse, Cathrine; Trentemøller, Stine

    Break the Pattern! A critical enquiry into three scientific workplace cultures: Hercules, Caretakers and Worker Bees is the third publication of the international three year long project "Understanding Puzzles in the Gendered European Map" (UPGEM). By contrasting empirical findings from academic ...... (physics in culture) and discuss how physics as and in culture influence the perception of science, of work and family life, of the interplay between religion and science as well as how physics as culture can either hinder or promote the career of female scientists....

  1. INTERACTIONS BETWEEN MODULATED LUMINANCE PATTERNS AND RANDOM-DOT PATTERNS

    NARCIS (Netherlands)

    CORNELISSEN, FW; KOOIJMAN, AC

    1994-01-01

    It has been suggested that density modulated random-dot patterns can be used to study higher order pattern vision [Van Meeteren and Barlow (1981) Vision Research, 21, 765-777]. The high contrast dots of which the pattern is composed, are assumed to be reliably transduced-and transmitted by the lower

  2. Archetypes as action patterns.

    Science.gov (United States)

    Hogenson, George B

    2009-06-01

    The discovery of mirror neurons by researchers at the University of Parma promises to radically alter our understanding of fundamental cognitive and affective states. This paper explores the relationship of mirror neurons to Jung's theory of archetypes and proposes that archetypes may be viewed as elementary action patterns. The paper begins with a review of a proposed interpretation of the fainting spells of S. Freud in his relationship with Jung as an example of an action pattern that also defines an archetypal image. The challenge that mirror neurons present to traditional views in analytical psychology and psychoanalysis, however, is that they operate without recourse to a cognitive processing element. This is a position that is gaining increasing acceptance in other fields as well. The paper therefore reviews the most recent claims made by the Boston Process of Change Study Group as well as conclusions drawn from dynamic systems views of development and theoretical robotics to underline the conclusion that unconscious agency is not a requirement for coherent action. It concludes with the suggestion that this entire body of research may lead to the conclusion that the dynamic unconscious is an unnecessary hypothesis in psychoanalysis and analytical psychology.

  3. Patterns of Negotiation

    Science.gov (United States)

    Sood, Suresh; Pattinson, Hugh

    Traditionally, face-to-face negotiations in the real world have not been looked at as a complex systems interaction of actors resulting in a dynamic and potentially emergent system. If indeed negotiations are an outcome of a dynamic interaction of simpler behavior just as with a complex system, we should be able to see the patterns contributing to the complexities of a negotiation under study. This paper and the supporting research sets out to show B2B (business-to-business) negotiations as complex systems of interacting actors exhibiting dynamic and emergent behavior. This paper discusses the exploratory research based on negotiation simulations in which a large number of business students participate as buyers and sellers. The student interactions are captured on video and a purpose built research method attempts to look for patterns of interactions between actors using visualization techniques traditionally reserved to observe the algorithmic complexity of complex systems. Students are videoed negotiating with partners. Each video is tagged according to a recognized classification and coding scheme for negotiations. The classification relates to the phases through which any particular negotiation might pass, such as laughter, aggression, compromise, and so forth — through some 30 possible categories. Were negotiations more or less successful if they progressed through the categories in different ways? Furthermore, does the data depict emergent pathway segments considered to be more or less successful? This focus on emergence within the data provides further strong support for face-to-face (F2F) negotiations to be construed as complex systems.

  4. Female Pattern Hair Loss

    Science.gov (United States)

    Herskovitz, Ingrid; Tosti, Antonella

    2013-01-01

    Context: Female pattern hair loss (FPHL) also known as female androgenetic alopecia is a common condition afflicting millions of women that can be cosmetically disrupting. Prompt diagnosis and treatment are essential for obtaining optimal outcome. This review addresses the clinical presentation of female pattern hair loss, its differential diagnosis and treatment modalities. Evidence Acquisition: A) Diffuse thinning of the crown region with preservation of the frontal hairline (Ludwig’s type) B) The “Christmas tree pattern” where the thinning is wider in the frontal scalp giving the alopecic area a triangular shaped figure resembling a christmas tree. C) Thinning associated with bitemporal recession (Hamilton type). Generally, FPHL is not associated with elevated androgens. Less commonly females with FPHL may have other skin or general signs of hyperandrogenism such as hirsutism, acne, irregular menses, infertility, galactorrhea and insulin resistance. The most common endocrinological abnormality associated with FPHL is polycystic ovarian syndrome (PCOS). Results: The most important diseases to consider in the differential diagnosis of FPHL include Chronic Telogen Effluvium (CTE), Permanent Alopecia after Chemotherapy (PAC), Alopecia Areata Incognito (AAI) and Frontal Fibrosing Alopecia (FFA). This review describes criteria for distinguishing these conditions from FPHL. Conclusions: The only approved treatment for FPHL, which is 2% topical Minoxidil, should be applied at the dosage of 1ml twice day for a minimum period of 12 months. This review will discuss off-label alternative modalities of treatment including 5-alfa reductase inhibitors, antiandrogens, estrogens, prostaglandin analogs, lasers, light treatments and hair transplantation. PMID:24719635

  5. Hidden patterns of reciprocity.

    Science.gov (United States)

    Syi

    2014-03-21

    Reciprocity can help the evolution of cooperation. To model both types of reciprocity, we need the concept of strategy. In the case of direct reciprocity there are four second-order action rules (Simple Tit-for-tat, Contrite Tit-for-tat, Pavlov, and Grim Trigger), which are able to promote cooperation. In the case of indirect reciprocity the key component of cooperation is the assessment rule. There are, again, four elementary second-order assessment rules (Image Scoring, Simple Standing, Stern Judging, and Shunning). The eight concepts can be formalized in an ontologically thin way we need only an action predicate and a value function, two agent concepts, and the constant of goodness. The formalism helps us to discover that the action and assessment rules can be paired, and that they show the same patterns. The logic of these patterns can be interpreted with the concept of punishment that has an inherent paradoxical nature. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Harmonic Patterns in Forex Trading

    OpenAIRE

    Nemček, Sebastian

    2013-01-01

    This diploma thesis is committed to examination of validity of Harmonic Patterns in Forex trading. Scott Carney described existing and introduced new Harmonic Patterns in 1999 in his book Harmonic Trader. These patterns use the Fibonacci principle to analyze price action and to provide both bullish and bearish trading signals. The goal of this thesis is to find out whether harmonic trading strategy on selected pairs is profitable in FX market, which patterns are the most profitable and what i...

  7. The Effects of Fracture Anisotropy on the Damage Pattern and Seismic Radiation from a Chemical Explosion in a Granite Quarry

    Science.gov (United States)

    Rogers-Martinez, M. A.; Sammis, C. G.; Ezzedine, S. M.

    2017-12-01

    As part of the New England Damage Experiment (NEDE) a 122.7 kg Heavy ANFO charge was detonated at a depth of 13 m in a granite quarry in Barre Vt. Subsequent drill cores from the source region revealed that most of the resultant fracturing was concentrated in the rift plane of the highly anisotropic Barre granite. We simulated this explosion using a dynamic damage mechanics model embedded in the ABAQUS 3D finite element code. The damage mechanics was made anisotropic by taking the critical stress intensity factor to be a function of azimuth in concert with the physics of interacting parallel fractures and laboratory studies of anisotropic granite. In order to identify the effects of anisotropy, the explosion was also simulated assuming 1) no initial damage (pure elasticity) and 2) isotropic initial damage. For the anisotropic case, the calculated fracture pattern simulated that observed in NEDE. The simulated seismic radiation looked very much like that from a tensile fracture oriented in the rift plane, and similar to the crack-like moment tensor observed in the far field of many nuclear explosions.

  8. Making sense of design patterns

    NARCIS (Netherlands)

    Hoekstra, R.; Breuker, J.

    2010-01-01

    This paper discusses the way in which design patterns may improve the current practice of ontology engineering. It presents five requirements that go beyond the current state of the art of collecting and curating design patterns. We build on the thesis outlined in [17] that design patterns should be

  9. Soft lithography of ceramic patterns

    NARCIS (Netherlands)

    Göbel, Ole; Nedelcu, M.; Steiner, U.

    2007-01-01

    Polymer-based precursor solutions are patterned using a soft-lithographic patterning technique to yield sub-micrometer-sized ceramic patterns. By using a polymer-metal-nitrate solution as a lithographic resist, we demonstrate a micromolding procedure using a simple rubber stamp that yields a

  10. Patterns of inclusion

    DEFF Research Database (Denmark)

    Pedersen, Alex Young; Nørgård, Rikke Toft; Köppe, Christian

    2018-01-01

    Reconsidering the concept of digital citizenship and the essential component of education the authors propose that the concept of Hybrid Education may serve both as a guideline for the utilization of digital technologies in education and as a methodology for fostering new forms of participation......, inclusion and engagement in society. Following T.H. Marshall’s conception of citizenship the authors suggest that becoming, belonging and the capabilities to do so is essential to digital citizenship in a culturally diverse and digitally mediated world. The paper presents a theory-based, value driven...... for Hybrid Education that are directly applicable in relation to the concept of digital citizenship. The process introduces a value-based and vision-driven design pattern approach to innovation in education by framing and aligning values and visions of the participants. This work resulted in approximately 85...

  11. Female pattern hair loss

    Directory of Open Access Journals (Sweden)

    Archana Singal

    2013-01-01

    Full Text Available Female pattern hair loss (FPHL is a common cause of hair loss in women characterized by diffuse reduction in hair density over the crown and frontal scalp with retention of the frontal hairline. Its prevalence increases with advancing age and is associated with significant psychological morbidity. The pathophysiology of FPHL is still not completely understood and seems to be multifactorial. Although androgens have been implicated, the involvement of androgen-independent mechanisms is evident from frequent lack of clinical or biochemical markers of hyperandrogenism in affected women. The role of genetic polymorphisms involving the androgen and estrogen receptors is being increasingly recognized in its causation and predicting treatment response to anti-androgens. There are different clinical patterns and classifications of FPHL, knowledge of which facilitates patient management and research. Chronic telogen effluvium remains as the most important differential diagnosis. Thorough history, clinical examination, and evaluation are essential to confirm diagnosis. Patients with clinical signs of androgen excess require assessment of biochemical parameters and imaging studies. It is prudent to screen the patients for metabolic syndrome and cardiovascular risk factors. The treatment comprises medical and/or surgical modalities. Medical treatment should be initiated early as it effectively arrests hair loss progression rather than stimulating regrowth. Minoxidil continues to be the first line therapy whereas anti-androgens form the second line of treatment. The progressive nature of FPHL mandates long-term treatment for sustained effect. Medical therapy may be supplemented with cosmetic concealment in those desirous of greater hair density. Surgery may be worthwhile in some carefully selected patients.

  12. Personal continuous route pattern mining

    Institute of Scientific and Technical Information of China (English)

    Qian YE; Ling CHEN; Gen-cai CHEN

    2009-01-01

    In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

  13. Pattern optimizing verification of self-align quadruple patterning

    Science.gov (United States)

    Yamato, Masatoshi; Yamada, Kazuki; Oyama, Kenichi; Hara, Arisa; Natori, Sakurako; Yamauchi, Shouhei; Koike, Kyohei; Yaegashi, Hidetami

    2017-03-01

    Lithographic scaling continues to advance by extending the life of 193nm immersion technology, and spacer-type multi-patterning is undeniably the driving force behind this trend. Multi-patterning techniques such as self-aligned double patterning (SADP) and self-aligned quadruple patterning (SAQP) have come to be used in memory devices, and they have also been adopted in logic devices to create constituent patterns in the formation of 1D layout designs. Multi-patterning has consequently become an indispensible technology in the fabrication of all advanced devices. In general, items that must be managed when using multi-patterning include critical dimension uniformity (CDU), line edge roughness (LER), and line width roughness (LWR). Recently, moreover, there has been increasing focus on judging and managing pattern resolution performance from a more detailed perspective and on making a right/wrong judgment from the perspective of edge placement error (EPE). To begin with, pattern resolution performance in spacer-type multi-patterning is affected by the process accuracy of the core (mandrel) pattern. Improving the controllability of CD and LER of the mandrel is most important, and to reduce LER, an appropriate smoothing technique should be carefully selected. In addition, the atomic layer deposition (ALD) technique is generally used to meet the need for high accuracy in forming the spacer film. Advances in scaling are accompanied by stricter requirements in the controllability of fine processing. In this paper, we first describe our efforts in improving controllability by selecting the most appropriate materials for the mandrel pattern and spacer film. Then, based on the materials selected, we present experimental results on a technique for improving etching selectivity.

  14. Patterns in the mind

    Directory of Open Access Journals (Sweden)

    Acosta Alejandro

    1999-06-01

    Full Text Available

     A mediados de la década de los noventa, el lingüista estadounidense Ray Jackendoff, meditando acerca de la situación de los avances en su campo de trabajo, publicó el libro Patterns in the Mind con el objetivo de poner al alcance del público no especializado los avances de la psicología cognitiva a partir de los postulados básicos de la revolución lingüística y cognitiva que
    floreció gracias a los trabajos del también lingüista norteamericano Noam Chomsky, a finales de la década de los cincuenta y principios de la de los sesenta. Su presencia en el desarrollo de esta nueva etapa del estudio del lenguaje y sus intereses en las nuevas teorías psicológicas 10 ubicaron en un marco teórico que comprende postulados acerca de la organización modular de las estructuras y procesos mentales, el innatismo de este tipo de organización y la existencia de una serie de patrones que rigen la construcción de gramáticas mentalesinconscientes para diversos dominios de la naturaleza humana.

  15. Childlessness patterns in Taiwan.

    Science.gov (United States)

    Poston Dl

    1988-06-01

    Taiwan is a newly developed and industrialized area, and along with Korea, Brazil, Argentina, and a few other countries, belongs in a special class of recently industrialized areas. Taiwan has been undergoing large-scale modernization since the 1950s when the Nationalist government 1st began to implement land reform programs and today is 1 of the showcase of newly developed areas of the world. Demographic transition theory shows that fertility is negatively associated with modernization. During the past 3 decades, fertility in Taiwan has followed this pattern in a dramatic manner. Studies of childlessness conducted in Western countries have shown also that as the modernizing influences continue, fertility declines, and childlessness increases as it becomes more and more voluntary. Subregions with the highest levels of modernization and the lowest fertility rates should therefore be characterized by the highest levels of childlessness, particularly among younger women, and vice versa. Given the levels of socioeconomic and demographic development in Taiwan and its subregions circa 1980, as well as its variability among the hsiens and major cities, the author would expect to find higher levels of childlessness in the more developed localities, and lower levels in the less developed subregions. This hypothesis is tested with data from the 1980 Census of Population and Housing: General Report, Taiwan--Fukien Area (Republic of China, 1982) and the 1980 Taiwan--Fukien Demographic Fact Book (Republic of China, 1980).

  16. Structure of multidimensional patterns

    International Nuclear Information System (INIS)

    Smith, S.P.

    1982-01-01

    The problem of describing the structure of multidimensional data is important in exploratory data analysis, statistical pattern recognition, and image processing. A data set is viewed as a collection of points embedded in a high dimensional space. The primary goal of this research is to determine if the data have any clustering structure; such a structure implies the presence of class information (categories) in the data. A statistical hypothesis is used in the decision making. To this end, data with no structure are defined as data following the uniform distribution over some compact convex set in K-dimensional space, called the sampling window. This thesis defines two new tests for uniformity along with various sampling window estimators. The first test is a volume-based test which captures density changes in the data. The second test compares a uniformly distributed sample to the data by using the minimal spanning tree (MST) of the polled samples. Sampling window estimators are provided for simple sampling windows and use the convex hull of the data as a general sampling window estimator. For both of the tests for uniformity, theoretical results are provided on their size, and study their size and power against clustered alternatives is studied. Simulation is also used to study the efficacy of the sampling window estimators

  17. Pattern recognition in spectra

    International Nuclear Information System (INIS)

    Gebran, M; Paletou, F

    2017-01-01

    We present a new automated procedure that simultaneously derives the effective temperature T eff , surface gravity log g , metallicity [ Fe/H ], and equatorial projected rotational velocity v e sin i for stars. The procedure is inspired by the well-known PCA-based inversion of spectropolarimetric full-Stokes solar data, which was used both for Zeeman and Hanle effects. The efficiency and accuracy of this procedure have been proven for FGK, A, and late type dwarf stars of K and M spectral types. Learning databases are generated from the Elodie stellar spectra library using observed spectra for which fundamental parameters were already evaluated or with synthetic data. The synthetic spectra are calculated using ATLAS9 model atmospheres. This technique helped us to detect many peculiar stars such as Am, Ap, HgMn, SiEuCr and binaries. This fast and efficient technique could be used every time a pattern recognition is needed. One important application is the understanding of the physical properties of planetary surfaces by comparing aboard instrument data to synthetic ones. (paper)

  18. A Database Integrity Pattern Language

    Directory of Open Access Journals (Sweden)

    Octavian Paul ROTARU

    2004-08-01

    Full Text Available Patterns and Pattern Languages are ways to capture experience and make it re-usable for others, and describe best practices and good designs. Patterns are solutions to recurrent problems.This paper addresses the database integrity problems from a pattern perspective. Even if the number of vendors of database management systems is quite high, the number of available solutions to integrity problems is limited. They all learned from the past experience applying the same solutions over and over again.The solutions to avoid integrity threats applied to in database management systems (DBMS can be formalized as a pattern language. Constraints, transactions, locks, etc, are recurrent integrity solutions to integrity threats and therefore they should be treated accordingly, as patterns.

  19. Dietary patterns and colorectal cancer.

    Science.gov (United States)

    Tayyem, Reema F; Bawadi, Hiba A; Shehadah, Ihab; Agraib, Lana M; AbuMweis, Suhad S; Al-Jaberi, Tareq; Al-Nusairr, Majed; Bani-Hani, Kamal E; Heath, Dennis D

    2017-06-01

    Dietary pattern and lifestyle have been reported to be important risk factors in the development of colorectal cancer (CRC). However, the mechanism of action of dietary factors in CRC disease is unclear. The aim of this study is the examination of several dietary choices and their potential association with the risk of developing CRC. Dietary data was collected from 220 subjects who were previously diagnosed with CRC, and 281 control subjects (matched by age, gender, occupation and marital status). The data was collected between January 2010 and December 2012, using interview-based questionnaires. Multivariate logistic regression was used to estimate the relationship between dietary choices and risk of developing colorectal cancer. Factor analysis revealed three major dietary patterns. The first pattern we identified as the "Healthy Pattern", the second was identified as "High Sugar/High Tea Pattern" and the third as "Western Pattern". In the Healthy Pattern group we found a 10.54% variation in food intake, while the intake variation was 11.64% in the Western Pattern. After adjusting for confounding factors, the Western Pattern food choice was found to be significantly associated with an increased risk of developing CRC (OR = 1.88; 95% CI = 1.12-3.16). The results for the Healthy and High-Sugar/High Tea Patterns showed a decrease, but the statistic was not significant for the risk of CRC development. The Western Pattern of dietary choice was directly associated with CRC. The association between the dietary food choice in the Healthy and High-Sugar/High Tea Patterns and colorectal cancer needs further study in our Jordanian population. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  20. Energy demand patterns

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, L; Schipper, L; Meyers, S; Sathaye, J; Hara, Y

    1984-05-01

    This report brings together three papers on energy demand presented at the Energy Research Priorities Seminar held in Ottawa on 8-10 August 1983. The first paper suggests a framework in which energy demand studies may be organized if they are to be useful in policy-making. Disaggregation and the analysis of the chain of energy transformations are possible paths toward more stable and reliable parameters. The second paper points to another factor that leads to instability in sectoral parameters, namely a changeover from one technology to another; insofar as technologies producing a product (or service) vary in their energy intensity, a technological shift will also change the energy intensity of the product. Rapid technological change is characteristic of some sectors in developing countries, and may well account for the high aggregate GDP-elasticities of energy consumption observed. The third paper begins with estimates of these elasticities, which were greater than one for all the member countries of the Asian Development Bank in 1961-78. The high elasticities, together with extreme oil dependence, made them vulnerable to the drastic rise in the oil price after 1973. The author distinguishes three diverging patterns of national experience. The oil-surplus countries naturally gained from the rise in the oil price. Among oil-deficit countries, the newly industrialized countries expanded their exports so rapidly that the oil crisis no longer worried them. For the rest, balance of payments adjustments became a prime concern of policy. Whether they dealt with the oil bill by borrowing, by import substitution, or by demand restraint, the impact of energy on their growth was unmistakable. The paper also shows why energy-demand studies, and energy studies in general, deserve to be taken seriously. 16 refs., 4 figs., 18 tabs.

  1. Patterns of ocular trauma

    International Nuclear Information System (INIS)

    Babar, T.F.; Khan, M.T.; Marwat, M.; Shah, A.; Murad, Y.; Khan, M.D.

    2007-01-01

    To describe the patterns of ocular trauma, cause of injury and its effects on eye. A retrospective case series. Medical records of 1105 patients admitted with ocular trauma were reviewed. The details of patients regarding age, gender, literacy, cause of injury and its effects on eye were entered into specially-designed performa. Sample selection consisted of all patients with history of ocular trauma and who were admitted to hospital. Population details consisted patients who were referred to the hospital from all parts of N.W.F.P. Thus, the frequency of trauma in the hospital admissions was analysed. Ophthalmic trauma comprised 6.78% of the hospital admission. One thousand one hundred and five patients presented with eye injuries. Out of them, 21 patients suffered from trauma to both eyes. Almost 80% patients were male and 69% patients were below 30 years of age. Delayed presentation was more common and 63.61% patients presented after one week. Open globe injuries were more common (520 eyes (46.18%)) than closed globe injuries (484 eyes (42.98%)). 23.26% of open globe injuries were associated with intraocular and intra-orbital foreign bodies. Superficial non-perforating, eyelid and adnexal and burns were seen in 122 eyes (10.83%). Among the complications, lens damage and hyphema was seen in more than 50% of the patients, 16.60% eyes were infected at the time of admission and 4.88% of eyes needed enucleation or evisceration. The common causes of injury were violence in 37.37%, occupational in 24.43% and domestic accidents in 19.18%. Ophthalmic trauma is a major public health problem. Majority of the involved are male and under 30 years of age. Delayed presentation is more common. Open globe injuries are more frequent. Violence and occupational injuries are the major causes. (author)

  2. Patterns for Parallel Software Design

    CERN Document Server

    Ortega-Arjona, Jorge Luis

    2010-01-01

    Essential reading to understand patterns for parallel programming Software patterns have revolutionized the way we think about how software is designed, built, and documented, and the design of parallel software requires you to consider other particular design aspects and special skills. From clusters to supercomputers, success heavily depends on the design skills of software developers. Patterns for Parallel Software Design presents a pattern-oriented software architecture approach to parallel software design. This approach is not a design method in the classic sense, but a new way of managin

  3. Professional Java EE design patterns

    CERN Document Server

    Yener, Murat

    2014-01-01

    Master Java EE design pattern implementation to improve your design skills and your application's architecture Professional Java EE Design Patterns is the perfect companion for anyone who wants to work more effectively with Java EE, and the only resource that covers both the theory and application of design patterns in solving real-world problems. The authors guide readers through both the fundamental and advanced features of Java EE 7, presenting patterns throughout, and demonstrating how they are used in day-to-day problem solving. As the most popular programming language in community-dri

  4. Patterning nanocrystals using DNA

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Shara Carol [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    One of the goals of nanotechnology is to enable programmed self-assembly of patterns made of various materials with nanometer-sized control. This dissertation describes the results of experiments templating arrangements of gold and semiconductor nanocrystals using 2'-deoxyribonucleic acid (DNA). Previously, simple DNA-templated linear arrangements of two and three nanocrystals structures have been made.[1] Here, we have sought to assemble larger and more complex nanostructures. Gold-DNA conjugates with 50 to 100 bases self-assembled into planned arrangements using strands of DNA containing complementary base sequences. We used two methods to increase the complexity of the arrangements: using branched synthetic doublers within the DNA covalent backbone to create discrete nanocrystal groupings, and incorporating the nanocrystals into a previously developed DNA lattice structure [2][3] that self-assembles from tiles made of DNA double-crossover molecules to create ordered nanoparticle arrays. In the first project, the introduction of a covalently-branched synthetic doubler reagent into the backbone of DNA strands created a branched DNA ''trimer.'' This DNA trimer templated various structures that contained groupings of three and four gold nanoparticles, giving promising, but inconclusive transmission electron microscopy (TEM) results. Due to the presence of a variety of possible structures in the reaction mixtures, and due to the difficulty of isolating the desired structures, the TEM and gel electrophoresis results for larger structures having four particles, and for structures containing both 5 and 10 nm gold nanoparticles were inconclusive. Better results may come from using optical detection methods, or from improved sample preparation. In the second project, we worked toward making two-dimensional ordered arrays of nanocrystals. We replicated and improved upon previous results for making DNA lattices, increasing the size of the lattices

  5. Elastic strain relaxation in interfacial dislocation patterns: II. From long- and short-range interactions to local reactions

    Science.gov (United States)

    Vattré, A.

    2017-08-01

    The long- and short-range interactions as well as planar reactions between two infinitely periodic sets of crossing dislocations are investigated using anisotropic elasticity theory in face- (fcc) and body- (bcc) centered cubic materials. Two preliminary cases are proposed to examine the substantial changes in the elastic stress states and the corresponding strain energies due to a slight rearrangement in the internal dislocation geometries and characters. In general, significant differences and discrepancies resulting from the considered cubic crystal structure and the approximation of isotropic elasticity are exhibited. In a third scenario, special attention is paid to connecting specific internal dislocation structures from the previous cases with non-equilibrium configurations predicted by the quantized Frank-Bilby equation for the (111) fcc and (110) bcc twist grain boundaries. The present solutions lead to the formation of energetically favorable dislocation junctions with non-randomly strain-relaxed configurations of lower energy. In particular, the local dislocation interactions and reactions form equilibrium hexagonal-shaped patterns with planar three-fold dislocation nodes without producing spurious far-field stresses.Numerical application results are presented from a selection of cubic metals including aluminum, copper, tantalum, and niobium. In contrast to the fcc materials, asymmetric dislocation nodes occur in the anisotropic bcc cases, within which the minimum-energy paths for predicting the fully strain-relaxed dislocation patterns depend on the Zener anisotropic factor with respect to unity. The associated changes in the dislocation structures as well as the removal of the elastic strain energy upon relaxations are quantified and also discussed.

  6. Capillarity Guided Patterning of Microliquids.

    Science.gov (United States)

    Kang, Myeongwoo; Park, Woohyun; Na, Sangcheol; Paik, Sang-Min; Lee, Hyunjae; Park, Jae Woo; Kim, Ho-Young; Jeon, Noo Li

    2015-06-01

    Soft lithography and other techniques have been developed to investigate biological and chemical phenomena as an alternative to photolithography-based patterning methods that have compatibility problems. Here, a simple approach for nonlithographic patterning of liquids and gels inside microchannels is described. Using a design that incorporates strategically placed microstructures inside the channel, microliquids or gels can be spontaneously trapped and patterned when the channel is drained. The ability to form microscale patterns inside microfluidic channels using simple fluid drain motion offers many advantages. This method is geometrically analyzed based on hydrodynamics and verified with simulation and experiments. Various materials (i.e., water, hydrogels, and other liquids) are successfully patterned with complex shapes that are isolated from each other. Multiple cell types are patterned within the gels. Capillarity guided patterning (CGP) is fast, simple, and robust. It is not limited by pattern shape, size, cell type, and material. In a simple three-step process, a 3D cancer model that mimics cell-cell and cell-extracellular matrix interactions is engineered. The simplicity and robustness of the CGP will be attractive for developing novel in vitro models of organ-on-a-chip and other biological experimental platforms amenable to long-term observation of dynamic events using advanced imaging and analytical techniques. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Retirement Patterns and Income Inequality

    Science.gov (United States)

    Fasang, Anette Eva

    2012-01-01

    How do social policies shape life courses, and which consequences do different life course patterns hold for individuals? This article engages the example of retirement in Germany and Britain to analyze life course patterns and their consequences for income inequality. Sequence analysis is used to measure retirement trajectories. The liberal…

  8. Pattern replication by confined dewetting

    NARCIS (Netherlands)

    Harkema, S.; Schäffer, E.; Morariu, M.D.; Steiner, U

    2003-01-01

    The dewetting of a polymer film in a confined geometry was employed in a pattern-replication process. The instability of dewetting films is pinned by a structured confining surface, thereby replicating its topographic pattern. Depending on the surface energy of the confining surface, two different

  9. Hostility, drinking pattern and mortality

    DEFF Research Database (Denmark)

    Boyle, Stephen H; Mortensen, Laust Hvas; Grønbaek, Morten

    2008-01-01

    This study examined the association of hostility to drinking pattern and whether this association mediated the relation of hostility to mortality.......This study examined the association of hostility to drinking pattern and whether this association mediated the relation of hostility to mortality....

  10. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  11. Chopper model of pattern recognition

    NARCIS (Netherlands)

    van Hemmen, J.L.; Enter, A.C.D. van

    A simple model is proposed that allows an efficient storage and retrieval of random patterns. Also correlated patterns can be handled. The data are stored in an Ising-spin system with ferromagnetic interactions between all the spins and the main idea is to "chop" the system along the boundaries

  12. Hand aperture patterns in prehension

    NARCIS (Netherlands)

    Bongers, Raoul M.; Zaal, Frank T. J. M.; Jeannerod, Marc

    Although variations in the standard prehensile pattern can be found in the literature, these alternative patterns have never been studied systematically. This was the goal of the current paper. Ten participants picked up objects with a pincer grip. Objects (3, 5, or 7 cm in diameter) were placed at

  13. Dynamic Skin Patterns in Cephalopods

    Directory of Open Access Journals (Sweden)

    Martin J. How

    2017-06-01

    Full Text Available Cephalopods are unrivaled in the natural world in their ability to alter their visual appearance. These mollusks have evolved a complex system of dermal units under neural, hormonal, and muscular control to produce an astonishing variety of body patterns. With parallels to the pixels on a television screen, cephalopod chromatophores can be coordinated to produce dramatic, dynamic, and rhythmic displays, defined collectively here as “dynamic patterns.” This study examines the nature, context, and potential functions of dynamic patterns across diverse cephalopod taxa. Examples are presented for 21 species, including 11 previously unreported in the scientific literature. These range from simple flashing or flickering patterns, to highly complex passing wave patterns involving multiple skin fields.

  14. Dynamic Skin Patterns in Cephalopods

    Science.gov (United States)

    How, Martin J.; Norman, Mark D.; Finn, Julian; Chung, Wen-Sung; Marshall, N. Justin

    2017-01-01

    Cephalopods are unrivaled in the natural world in their ability to alter their visual appearance. These mollusks have evolved a complex system of dermal units under neural, hormonal, and muscular control to produce an astonishing variety of body patterns. With parallels to the pixels on a television screen, cephalopod chromatophores can be coordinated to produce dramatic, dynamic, and rhythmic displays, defined collectively here as “dynamic patterns.” This study examines the nature, context, and potential functions of dynamic patterns across diverse cephalopod taxa. Examples are presented for 21 species, including 11 previously unreported in the scientific literature. These range from simple flashing or flickering patterns, to highly complex passing wave patterns involving multiple skin fields. PMID:28674500

  15. Nonlinear waves and pattern dynamics

    CERN Document Server

    Pelinovsky, Efim; Mutabazi, Innocent

    2018-01-01

    This book addresses the fascinating phenomena associated with nonlinear waves and spatio-temporal patterns. These appear almost everywhere in nature from sand bed forms to brain patterns, and yet their understanding still presents fundamental scientific challenges. The reader will learn here, in particular, about the current state-of-the art and new results in: Nonlinear water waves: resonance, solitons, focusing, Bose-Einstein condensation, as well as and their relevance for the sea environment (sea-wind interaction, sand bed forms, fiber clustering) Pattern formation in non-equilibrium media: soap films, chimera patterns in oscillating media, viscoelastic Couette-Taylor flow, flow in the wake behind a heated cylinder, other pattern formation. The editors and authors dedicate this book to the memory of Alexander Ezersky, Professor of Fluid Mechanics at the University of Caen Normandie (France) from September 2007 to July 2016. Before 2007, he had served as a Senior Scientist at the Institute of Applied Physi...

  16. Mobile Design Pattern Gallery UI Patterns for Mobile Applications

    CERN Document Server

    Neil, Theresa

    2012-01-01

    When you're under pressure to produce a well designed, easy-to-navigate mobile app, there's no time to reinvent the wheel. This concise book provides a handy reference to 70 mobile app design patterns, illustrated by more than 400 screenshots from current iOS, Android, BlackBerry, WebOS, Windows Mobile, and Symbian apps. User experience professional Theresa Neil (Designing Web Interfaces) walks you through design patterns in 10 separate categories, including anti-patterns. Whether you're designing a simple iPhone application or one that's meant to work for every popular mobile OS on the mark

  17. Security patterns in practice designing secure architectures using software patterns

    CERN Document Server

    Fernandez-Buglioni, Eduardo

    2013-01-01

    Learn to combine security theory and code to produce secure systems Security is clearly a crucial issue to consider during the design and implementation of any distributed software architecture. Security patterns are increasingly being used by developers who take security into serious consideration from the creation of their work. Written by the authority on security patterns, this unique book examines the structure and purpose of security patterns, illustrating their use with the help of detailed implementation advice, numerous code samples, and descriptions in UML. Provides

  18. Pattern Classification in Kampo Medicine

    Directory of Open Access Journals (Sweden)

    S. Yakubo

    2014-01-01

    Full Text Available Pattern classification is very unique in traditional medicine. Kampo medical patterns have transformed over time during Japan’s history. In the 17th to 18th centuries, Japanese doctors advocated elimination of the Ming medical theory and followed the basic concepts put forth by Shang Han Lun and Jin Gui Yao Lue in the later Han dynasty (25–220 AD. The physician Todo Yoshimasu (1702–1773 emphasized that an appropriate treatment could be administered if a set of patterns could be identified. This principle is still referred to as “matching of pattern and formula” and is the basic concept underlying Kampo medicine today. In 1868, the Meiji restoration occurred, and the new government changed its policies to follow that of the European countries, adopting only Western medicine. Physicians trained in Western medicine played an important role in the revival of Kampo medicine, modernizing Kampo patterns to avoid confusion with Western biomedical terminology. In order to understand the Japanese version of traditional disorders and patterns, background information on the history of Kampo and its role in the current health care system in Japan is important. In this paper we overviewed the formation of Kampo patterns.

  19. Hand aperture patterns in prehension.

    Science.gov (United States)

    Bongers, Raoul M; Zaal, Frank T J M; Jeannerod, Marc

    2012-06-01

    Although variations in the standard prehensile pattern can be found in the literature, these alternative patterns have never been studied systematically. This was the goal of the current paper. Ten participants picked up objects with a pincer grip. Objects (3, 5, or 7cm in diameter) were placed at 30, 60, 90, or 120cm from the hands' starting location. Usually the hand was opened gradually to a maximum immediately followed by hand closing, called the standard hand opening pattern. In the alternative opening patterns the hand opening was bumpy, or the hand aperture stayed at a plateau before closing started. Two participants in particular delayed the start of grasping with respect to start of reaching, with the delay time increasing with object distance. For larger object distances and smaller object sizes, the bumpy and plateau hand opening patterns were used more often. We tentatively concluded that the alternative hand opening patterns extended the hand opening phase, to arrive at the appropriate hand aperture at the appropriate time to close the hand for grasping the object. Variations in hand opening patterns deserve attention because this might lead to new insights into the coordination of reaching and grasping. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Imaging patterns in elastofibroma dorsi

    International Nuclear Information System (INIS)

    Battaglia, M.; Vanel, D.; Pollastri, P.; Balladelli, A.; Alberghini, M.; Staals, E.L.; Monti, C.; Galletti, S.

    2009-01-01

    Introduction: Elastofibroma dorsi is a rare pseudotumor of the soft tissues. Its clinico-radiologic characteristics lead to a correct diagnosis. Material and methods: We followed 43 patients with elastofibroma dorsi with a confirmed histological diagnosis or on the basis of typical imaging pattern (ultrasound, CT, MR) confirmed by evolution. Results: Elastofibroma is prevalent in females, its onset occurs around 60 years of age and is most frequently localized in the deep subscapular region (93%), bilateral in 54% of cases. In 7% it was found in an atypical isolated suprascapular region, in 7% it was synchronous to that in the subscapular region. Four ultrasound patterns were detected: Type I (54%) inhomogeneous fasciculated, Type II (22%) inhomogeneous aspecific, Type III (15%) hyperechogeneous, Type IV (9%) hypoechogeneous. Three patterns were detected at CT and MR: Type A (84%) inhomogeneous fasciculated corresponding to Types I and III and partially to Type II ultrasound pattern, Type B (8%) inhomogeneous aspecific corresponding to Type II ultrasound pattern; Type C (8%) homogeneous isodense or isointense to the muscle corresponding to Type IV ultrasound pattern. Conclusion: A solid, slow-growing lesion, in the deep periscapular region in females aged between 50 and 60 years, with a typical fasciculated pattern is pathognomonic of elastofibroma dorsi and bilateral location convalidates diagnosis. Ultrasound is sufficient to orientate diagnosis. CT and/or MR are reserved only for non-fasciculated ultrasound patterns, when site is atypical or in candidates for surgery. Biopsy is reserved only in cases where integrated imaging shows a non-fasciculated pattern to differentiate it from other malignant lesions.

  1. Imaging patterns in elastofibroma dorsi

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, M. [Diagnostic Ultrasound, Istituto Ortopedico Rizzoli, Via Pupilli 1, 40136 Bologna (Italy)], E-mail: milva.battaglia@ior.it; Vanel, D. [Bone Tumor Center, Istituto Ortopedico Rizzoli, Bologna (Italy); Pollastri, P. [Diagnostic Ultrasound, Istituto Ortopedico Rizzoli, Via Pupilli 1, 40136 Bologna (Italy); Balladelli, A. [Laboratory of Oncologic Research, Istituto Ortopedico Rizzoli, Bologna (Italy); Alberghini, M. [Surgical Pathology, Istituto Ortopedico Rizzoli, Bologna (Italy); Staals, E.L. [5th Orthopaedic Division, Istituto Ortopedico Rizzoli, Bologna (Italy); Monti, C. [Radiology Department ' Casa Cura Madre Fortunata Toniolo' , Bologna (Italy); Galletti, S. [Diagnostic Ultrasound, Istituto Ortopedico Rizzoli, Via Pupilli 1, 40136 Bologna (Italy)

    2009-10-15

    Introduction: Elastofibroma dorsi is a rare pseudotumor of the soft tissues. Its clinico-radiologic characteristics lead to a correct diagnosis. Material and methods: We followed 43 patients with elastofibroma dorsi with a confirmed histological diagnosis or on the basis of typical imaging pattern (ultrasound, CT, MR) confirmed by evolution. Results: Elastofibroma is prevalent in females, its onset occurs around 60 years of age and is most frequently localized in the deep subscapular region (93%), bilateral in 54% of cases. In 7% it was found in an atypical isolated suprascapular region, in 7% it was synchronous to that in the subscapular region. Four ultrasound patterns were detected: Type I (54%) inhomogeneous fasciculated, Type II (22%) inhomogeneous aspecific, Type III (15%) hyperechogeneous, Type IV (9%) hypoechogeneous. Three patterns were detected at CT and MR: Type A (84%) inhomogeneous fasciculated corresponding to Types I and III and partially to Type II ultrasound pattern, Type B (8%) inhomogeneous aspecific corresponding to Type II ultrasound pattern; Type C (8%) homogeneous isodense or isointense to the muscle corresponding to Type IV ultrasound pattern. Conclusion: A solid, slow-growing lesion, in the deep periscapular region in females aged between 50 and 60 years, with a typical fasciculated pattern is pathognomonic of elastofibroma dorsi and bilateral location convalidates diagnosis. Ultrasound is sufficient to orientate diagnosis. CT and/or MR are reserved only for non-fasciculated ultrasound patterns, when site is atypical or in candidates for surgery. Biopsy is reserved only in cases where integrated imaging shows a non-fasciculated pattern to differentiate it from other malignant lesions.

  2. The convection patterns in microemulsions

    International Nuclear Information System (INIS)

    Korneta, W.; Lopez Quintela, M.A.; Fernandez Novoa, A.

    1991-07-01

    The Rayleigh-Benard convection in the microemulsion consisting of water (7.5%), cyclohexan (oil-61.7%) and diethylenglycolmonobutylether (surfactant-30.8%) is studied from the onset of convection to the phase separation. The five classes of convection patterns are observed and recorded on the video: localized travelling waves, travelling waves, travelling waves and localized steady rolls, steady rolls and steady polygons. The Fourier transforms and histograms of these patterns are presented. The origin of any pattern is discussed. The intermittent behaviour close to the phase separation was observed. Possible applications of the obtained results are suggested. (author). 6 refs, 4 figs

  3. Participation patterns in adult education

    DEFF Research Database (Denmark)

    Desjardins, Richard; Rubenson, Kjell

    2013-01-01

    This article focuses on evidence regarding cross-national patterns of participation in adult education and an interpretation of these patterns from an institutional and public policy perspective. The interpretation follows from the perspective that sustaining high and widely distributed levels...... problems that otherwise lead to underinvestment in skills and/or inequity in the distribution of access to education and training and hence skills. Hence, it is argued that institutional contexts and public policy measures condition participation patterns in adult education, and are thus worthwhile...

  4. Identifying modes of large whispering-gallery mode resonators from the spectrum and emission pattern

    DEFF Research Database (Denmark)

    Schunk, Gerhard; Fuerst, Josef U.; Förtsch, Michael

    2014-01-01

    Identifying the mode numbers in whispering-gallery mode resonators (WGMRs) is important for tailoring them to experimental needs. Here we report on a novel experimental mode analysis technique based on the combination of frequency analysis and far-field imaging for high mode numbers of large WGMR...

  5. Pattern recognition and string matching

    CERN Document Server

    Cheng, Xiuzhen

    2002-01-01

    The research and development of pattern recognition have proven to be of importance in science, technology, and human activity. Many useful concepts and tools from different disciplines have been employed in pattern recognition. Among them is string matching, which receives much theoretical and practical attention. String matching is also an important topic in combinatorial optimization. This book is devoted to recent advances in pattern recognition and string matching. It consists of twenty eight chapters written by different authors, addressing a broad range of topics such as those from classifica­ tion, matching, mining, feature selection, and applications. Each chapter is self-contained, and presents either novel methodological approaches or applications of existing theories and techniques. The aim, intent, and motivation for publishing this book is to pro­ vide a reference tool for the increasing number of readers who depend upon pattern recognition or string matching in some way. This includes student...

  6. A pattern theory of self

    Directory of Open Access Journals (Sweden)

    Shaun eGallagher

    2013-08-01

    Full Text Available I argue for a pattern theory of self as a useful way to organize an interdisciplinary approach to discussions of what constitutes a self. According to the pattern theory, a self is constituted by a number of characteristic features or aspects that may include minimal embodied, minimal experiential, affective, intersubjective, psychological/cognitive, narrative, extended and situated aspects. A pattern theory of self helps to clarify various interpretations of self as compatible or commensurable instead of thinking them in opposition, and it helps to show how various aspects of self may be related across certain dimensions. I also suggest that a pattern theory of self can help to adjudicate (or at least map the differences between the idea that the self correlates to self-referential processing in the cortical midline structures of the brain and other narrower or wider conceptions of self.

  7. A pattern theory of self.

    Science.gov (United States)

    Gallagher, Shaun

    2013-01-01

    I argue for a pattern theory of self as a useful way to organize an interdisciplinary approach to discussions of what constitutes a self. According to the pattern theory, a self is constituted by a number of characteristic features or aspects that may include minimal embodied, minimal experiential, affective, intersubjective, psychological/cognitive, narrative, extended, and situated aspects. A pattern theory of self helps to clarify various interpretations of self as compatible or commensurable instead of thinking them in opposition, and it helps to show how various aspects of self may be related across certain dimensions. I also suggest that a pattern theory of self can help to adjudicate (or at least map the differences) between the idea that the self correlates to self-referential processing in the cortical midline structures of the brain and other narrower or wider conceptions of self.

  8. Ecoscapes: Geographical Patternings of Relations

    Directory of Open Access Journals (Sweden)

    Aimar Ventsel

    2012-06-01

    Full Text Available Book review of the publication Ecoscapes: Geographical Patternings of Relations. Edited by Gary Backhaus and John Murungi. Lanham, Boulder, New York, Toronto, Oxford, Lexington Books, 2006, xxxiii+241 pp.

  9. Ecoscapes: Geographical Patternings of Relations

    Directory of Open Access Journals (Sweden)

    Aimar Ventsel

    2013-01-01

    Full Text Available Book review of the publication Ecoscapes: Geographical Patternings of Relations. Edited by Gary Backhaus and John Murungi. Lanham, Boulder, New York, Toronto, Oxford, Lexington Books, 2006, xxxiii+241 pp.

  10. County business patterns, 1996 : Nevada

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  11. County business patterns, 1997 : Wisconsin

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  12. County business patterns, 1997 : Arizona

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  13. County business patterns, 1997 : Wyoming

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  14. County business patterns, 1997 : Minnesota

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  15. County business patterns, 1996 : Colorado

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  16. County business patterns, 1996 : Montana

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  17. County business patterns, 1996 : Nebraska

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  18. County business patterns, 1996 : Kentucky

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  19. County business patterns, 1996 : Idaho

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  20. County business patterns, 1997 : Alabama

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  1. County business patterns, 1997 : Maryland

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  2. County business patterns, 1997 : Maine

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  3. County business patterns, 1996 : Utah

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  4. County business patterns, 1996 : Oklahoma

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  5. County business patterns, 1996 : Alaska

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  6. County business patterns, 1997 : Kansas

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  7. County business patterns, 1997 : Florida

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  8. County business patterns, 1997 : Oklahoma

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  9. County business patterns, 1997 : Michigan

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  10. County business patterns, 1997 : Tennessee

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  11. County business patterns, 1997 : Kentucky

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  12. County business patterns, 1996 : Louisiana

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  13. County business patterns, 1997 : Texas

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  14. County business patterns, 1997 : Virginia

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  15. County business patterns, 1996 : Delaware

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  16. County business patterns, 1997 : Idaho

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  17. County business patterns, 1997 : Nevada

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  18. County business patterns, 1996 : Wisconsin

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  19. County business patterns, 1996 : Arkansas

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  20. County business patterns, 1996 : Florida

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  1. County business patterns, 1997 : Mississippi

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  2. County business patterns, 1996 : Missouri

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  3. County business patterns, 1996 : Maryland

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  4. County business patterns, 1997 : Hawaii

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  5. County business patterns, 1996 : Ohio

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  6. County business patterns, 1996 : Alabama

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  7. County business patterns, 1997 : Alaska

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  8. County business patterns, 1996 : Iowa

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  9. County business patterns, 1996 : Georgia

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  10. County business patterns, 1996 : Michigan

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  11. County business patterns, 1996 : Texas

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  12. County business patterns, 1997 : Nebraska

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  13. County business patterns, 1997 : Massachusetts

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  14. County business patterns, 1997 : Indiana

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  15. County business patterns, 1996 : Pennsylvania

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  16. County business patterns, 1997 : Arkansas

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  17. County business patterns, 1997 : Colorado

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  18. County business patterns, 1996 : Arizona

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  19. County business patterns, 1997 : Oregon

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  20. County business patterns, 1997 : Georgia

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  1. County business patterns, 1997 : Missouri

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  2. County business patterns, 1997 : Illinois

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  3. County business patterns, 1997 : Utah

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  4. County business patterns, 1996 : Kansas

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  5. County business patterns, 1996 : Maine

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  6. County business patterns, 1997 : Pennsylvania

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  7. County business patterns, 1996 : Tennessee

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  8. County business patterns, 1997 : Ohio

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  9. County business patterns, 1996 : Vermont

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  10. County business patterns, 1996 : Wyoming

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  11. County business patterns, 1996 : Illinois

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  12. County business patterns, 1996 : Virginia

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  13. County business patterns, 1997 : Iowa

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  14. County business patterns, 1997 : Connecticut

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  15. County business patterns, 1996 : Hawaii

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  16. County business patterns, 1997 : Washington

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  17. County business patterns, 1997 : Vermont

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  18. County business patterns, 1996 : Oregon

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  19. County business patterns, 1996 : Minnesota

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  20. County business patterns, 1996 : California

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  1. County business patterns, 1996 : Indiana

    Science.gov (United States)

    1998-11-01

    County Business Patterns is an annual series that : provides subnational economic data by industry. The series : is useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  2. County business patterns, 1997 : Delaware

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  3. County business patterns, 1997 : Montana

    Science.gov (United States)

    1999-09-01

    County Business Patterns is an annual series that provides : subnational economic data by industry. The series is : useful for studying the economic activity of small areas; : analyzing economic changes over time; and as a benchmark : for statistical...

  4. Anastomosing Rivers are Disequilibrium Patterns

    NARCIS (Netherlands)

    Lavooi, E.; Haas, de T.; Kleinhans, M.G.; Makaske, B.; Smith, D.G.

    2010-01-01

    Anastomosing rivers have multiple interconnected channels that enclose floodbasins. Various theories have been proposed to explain this pattern, including an increased discharge conveyance and sediment transport capacity of multiple channels, or, alternatively, a tendency to avulse due to upstream

  5. Visualizing Data Patterns with Micromaps

    CERN Document Server

    Carr, Daniel B

    2010-01-01

    After more than 15 years of development drawing on research in cognitive psychology, statistical graphics, computer science, and cartography, micromap designs are becoming part of mainstream statistical visualizations. Bringing together the research of two leaders in this field, "Visualizing Data Patterns with Micromaps" presents the many design variations and applications of micromaps, which link statistical information to an organized set of small maps. This full-color book helps readers simultaneously explore the statistical and geographic patterns in their data. After illustratin

  6. Capacitance enhancement via electrode patterning

    International Nuclear Information System (INIS)

    Ho, Tuan A.; Striolo, Alberto

    2013-01-01

    The necessity of increasing the energy density in electric double layer capacitors to meet current demand is fueling fundamental and applied research alike. We report here molecular dynamics simulation results for aqueous electrolytes near model electrodes. Particular focus is on the effect of electrode patterning on the structure of interfacial electrolytes, and on the potential drop between the solid electrodes and the bulk electrolytes. The latter is estimated by numerically integrating the Poisson equation using the charge densities due to water and ions accumulated near the interface as input. We considered uniform and patterned electrodes, both positively and negatively charged. The uniformly charged electrodes are modeled as graphite. The patterned ones are obtained by removing carbon atoms from the top-most graphene layer, yielding nanoscopic squares and stripes patterns. For simplicity, the patterned electrodes are effectively simulated as insulators (the charge remains localized on the top-most layer of carbon atoms). Our simulations show that the patterns alter the structure of water and the accumulation of ions at the liquid-solid interfaces. Using aqueous NaCl solutions, we found that while the capacitance calculated for three positively charged electrodes did not change much, that calculated for the negatively charged electrodes significantly increased upon patterning. We find that both water structure and orientation, as well as ion accumulation affect the capacitance. As electrode patterning affects differently water structure and ion accumulation, it might be possible to observe ion-specific effects. These results could be useful for advancing our understanding of electric double layer capacitors, capacitive desalination processes, as well as of fundamental interfacial electrolytes properties

  7. Computer aided fringe pattern analysis

    Science.gov (United States)

    Sciammarella, Cesar A.

    The paper reviews the basic laws of fringe pattern interpretation. The different techniques that are currently utilized are presented using a common frame of reference stressing the fact that these techniques are different variations of the same basic principle. Digital and analog techniques are discussed. Currently available hardware is presented and the relationships between hardware and the operations of pattern fringe processing are pointed out. Examples are given to illustrate the ideas discussed in the paper.

  8. Quantum computing for pattern classification

    OpenAIRE

    Schuld, Maria; Sinayskiy, Ilya; Petruccione, Francesco

    2014-01-01

    It is well known that for certain tasks, quantum computing outperforms classical computing. A growing number of contributions try to use this advantage in order to improve or extend classical machine learning algorithms by methods of quantum information theory. This paper gives a brief introduction into quantum machine learning using the example of pattern classification. We introduce a quantum pattern classification algorithm that draws on Trugenberger's proposal for measuring the Hamming di...

  9. Plasma etching of patterned tungsten

    International Nuclear Information System (INIS)

    Franssila, S.

    1993-01-01

    Plasma etching of tungsten is discussed from the viewpoint of thin film structure and integrated circuit process engineering. The emphasis is on patterned tungsten etching for silicon device and X-ray mask fabrication. After introducing tungsten etch chemistries and mechanisms, microstructural aspects of tungsten films (crystal structure, grain size, film density, defects, impurities) in relation to etching are discussed. Approaches to etch process optimization are presented, and the current state-of-the-art of patterned tungsten etching is reviewed. (orig.)

  10. Patterns for Effectively Documenting Frameworks

    Science.gov (United States)

    Aguiar, Ademar; David, Gabriel

    Good design and implementation are necessary but not sufficient pre-requisites for successfully reusing object-oriented frameworks. Although not always recognized, good documentation is crucial for effective framework reuse, and often hard, costly, and tiresome, coming with many issues, especially when we are not aware of the key problems and respective ways of addressing them. Based on existing literature, case studies and lessons learned, the authors have been mining proven solutions to recurrent problems of documenting object-oriented frameworks, and writing them in pattern form, as patterns are a very effective way of communicating expertise and best practices. This paper presents a small set of patterns addressing problems related to the framework documentation itself, here seen as an autonomous and tangible product independent of the process used to create it. The patterns aim at helping non-experts on cost-effectively documenting object-oriented frameworks. In concrete, these patterns provide guidance on choosing the kinds of documents to produce, how to relate them, and which contents to include. Although the focus is more on the documents themselves, rather than on the process and tools to produce them, some guidelines are also presented in the paper to help on applying the patterns to a specific framework.

  11. Faraday instability on patterned surfaces

    Science.gov (United States)

    Feng, Jie; Rubinstein, Gregory; Jacobi, Ian; Stone, Howard

    2013-11-01

    We show how micro-scale surface patterning can be used to control the onset of the Faraday instability in thin liquid films. It is well known that when a liquid film on a planar substrate is subject to sufficient vibrational accelerations, the free surface destabilizes, exhibiting a family of non-linear standing waves. This instability remains a canonical problem in the study of spontaneous pattern formation, but also has practical uses. For example, the surface waves induced by the Faraday instability have been studied as a means of enhanced damping for mechanical vibrations (Genevaux et al. 2009). Also the streaming within the unstable layer has been used as a method for distributing heterogeneous cell cultures on growth medium (Takagi et al. 2002). In each of these applications, the roughness of the substrate significantly affects the unstable flow field. We consider the effect of patterned substrates on the onset and behavior of the Faraday instability over a range of pattern geometries and feature heights where the liquid layer is thicker than the pattern height. Also, we describe a physical model for the influence of patterned roughness on the destabilization of a liquid layer in order to improve the design of practical systems which exploit the Faraday instability.

  12. Career patterns of healthcare executives.

    Science.gov (United States)

    Fahey, D F; Myrtle, R C

    2001-02-01

    This research examines the job and career changes of healthcare executives and managers working in different segments of the healthcare industry in the western United States. The results suggest that the job and career patterns in the healthcare delivery sector are undergoing significant transformation. One third of the respondents reports that at least one of their last four job changes was involuntary or unplanned. One half of those attempted to make a career change. This study identifies four different executive and management career patterns. The most common was one of multiple career changes. The second pattern was that of a single career change, followed by a 'traditional' career in which one did not seek a career change. The final pattern was characterized as a movement back and forth between two different segments of the healthcare industry. Age, gender, marital status and education were not associated with any specific career pattern. The need to achieve results early in the respondent's career had a strong influence on career patterns. This study confirms the fluidity of career movement and the changing permeability between the various segments of the healthcare industry. It also suggests that career success increasingly will require broad management experience in those different segments.

  13. Generating potentially nilpotent full sign patterns

    NARCIS (Netherlands)

    Kim, I.J.; Olesky, D.D.; Shader, B.L.; Driessche, van den P.; Holst, van der H.; Vander Meulen, K.N.

    2009-01-01

    A sign pattern is a matrix with entries in {+,-, 0}. A full sign pattern has no zero entries. The refined inertia of a matrix pattern is defined and techniques are developed for constructing potentially nilpotent full sign patterns. Such patterns are spectrally arbitrary. These techniques can also

  14. The study of the dynamics of migration main radiologically significant isotopes in the near and far field Chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Bondarkov, M.; Bondarkov, D.; Maksymenko, A. [Chornobyl Center for Nuclear Safety, Radioactive Waste and Radioecology (Ukraine); Zheltonozhskaya, M.; Zheltonozhsky, V. [Institute for nuclear research (Ukraine)

    2014-07-01

    The study of the migration of {sup 90}Sr, {sup 137}Cs, {sup 241}Am and Pu isotopes in soil near Chernobyl nuclear power plant area, as well as the Chernigov region, Ukraine is described. Experiments were conducted using a semiconductor spectrometry and radiochemical separation of isotopes needed. The experimental data obtained were processed using a mathematical model that takes into account in convective component (fit parameter V-- linear velocity of radionuclide movement dependent upon soil moisture) and diffusive one (fit parameter D- diffusion coefficient) migration of isotopes. The parameter values in V and D of migration, in turn, allow us to estimate halftime of decontamination top five-centimeter layer of soil. The results obtained in this paper halftime of decontamination for the various isotopes and their comparison with those obtained by us and by other authors in the past 10-20 years, confirms the trend previously noticed by a significant speeding migration Radiostrontium compared with Radiocesium. It is shown that for all the types studied soils in the late phase of Chernobyl accident halftime of decontamination of the top 5 - cm soil layer for radiostrontium, and for radioactive cesium in the order of magnitude or more greater than the period of the physical half-life of the radionuclide that is, matching in the late phase of the accident change the exposure dose of radiation is mainly determined by the physical decay of the radionuclide. According to the estimated periods decontamination upper soil horizons of different migration mobility of radionuclides in soils exclusion zone reduced in number: {sup 90}Sr> {sup 137}Cs> {sup 241}Am ≥ {sup 238-240}Pu, migration mobility of isotopes of transuranic elements is very low. Document available in abstract form only. (authors)

  15. Estimation of Near-Field and Far-Field Dilutions for Site Selection of Effluent Outfall in a Coastal Region - A Case Study

    Digital Repository Service at National Institute of Oceanography (India)

    Naidu, V.S.

    . The effluent would move along the coast, and chances of reaching to the estuary are remote. Rise of the biological oxygen demand concentration to 2.9 mg/L above ambient is predicted at the release site. The water quality of Damanganga estuary would be restored...

  16. Far Field Sorption Data Bases for Performance Assessment of a High-Level Radioactive Waste Repository in an Undisturbed Opalinus Clay Host Rock

    International Nuclear Information System (INIS)

    Bradburry, M.; Baeyens, B.

    2003-08-01

    An Opalinus Clay formation in the Zuercher Weinland is under consideration by Nagra as a potential location for a high-level and long-Iived intermediate-level radioactive waste repository. Performance assessment studies will be performed for this site and the purpose of this report is to describe the procedures used to develop sorption data bases appropriate for an undisturbed Opalinus Clay host rock which are required for such safety analysis calculations. In tight, low water content argillaceous rock formations such as Opalinus Clay, there is uncertainty concerning the in situ pH/P CO 2 . In order to take this intrinsic uncertainty into account porewater chemistries were calculated for a reference case, pH = 7.24, and for two other pH values, 6.3 and 7.8. Sorption data bases are given for the three cases. The basis for the sorption data bases is 'in-house' sorption measurements for Cs(I), Sr(II), Ni(II), Eu(III), Sn(IV), Se(IV), Th(IV) and I(-I) carried out on Opalinus Clay samples from Mont Terri (Canton Jura) since at the time the experiments were performed no core samples from the Benken borehole (Zuercher Weinland) were available. The Opalinus Clay at Mont Terri and Benken are part of the same geological formation . Despite having directly measured data for the above key radionuclides, some of the required distribution ratios (Rd) used to generate the sorption data bases still came from the open literature. An important part of this report is concerned with describing the procedures whereby these selected literature Rd values were modified so as to apply to the Benken Opalinus Clay mineralogy and groundwater chemistries calculated at the three pH values given above. The resulting Rd values were then further modified using so-called Lab→Field transfer factors to produce sorption values which were appropriate to the in situ bulk rock for the selected range of water chemistry conditions. Finally, it is important to have some appreciation of the uncertainties associated with the selected Rd values in the sorption data bases. An attempt has been made in the report to move away from the unsatisfactory 'realistic/conservative' terminology and to develop a procedure for estimating uncertainty in a transparent and traceable manner. (author)

  17. Variations in Cell Surfaces of Estrogen Treated Breast Cancer Cells Detected by A Combined Instrument for Far-Field and Near-Field Microscopy

    Directory of Open Access Journals (Sweden)

    P. Perner

    2002-01-01

    Full Text Available The response of single breast cancer cells (cell line T‐47D to 17β‐estradiol (E2 under different concentrations was studied by using an instrument that allows to combine far‐field light microscopy with high resolution scanning near‐field (AFM/SNOM microscopy on the same cell. Different concentrations of E2 induce clearly different effects as well on cellular shape (in classical bright‐field imaging as on surface topography (atomic force imaging and absorbance (near‐field light transmission imaging. The differences range from a polygonal shape at zero via a roughly spherical shape at physiological up to a spindle‐like shape at un‐physiologically high concentrations. The surface topography of untreated control cells was found to be regular and smooth with small overall height modulations. At physiological E2 concentrations the surfaces became increasingly jagged as detected by an increase in membrane height. After application of the un‐physiological high E2 concentration the cell surface structures appeared to be smoother again with an irregular fine structure. The general behaviour of dose dependent differences was also found in the near‐field light transmission images. In order to quantify the treatment effects, line scans through the normalised topography images were drawn and a rate of co‐localisation between high topography and high transmission areas was calculated. The cell biological aspects of these observations are, so far, not studied in detail but measurements on single cells offer new perspectives to be empirically used in diagnosis and therapy control of breast cancers.

  18. Pre-shot simulations of far-field ground motion for the Source Physics Experiment (SPE) Explosions at the Climax Stock, Nevada National Security Site: SPE2

    Energy Technology Data Exchange (ETDEWEB)

    Mellors, R J; Rodgers, A; Walter, W; Ford, S; Xu, H; Matzel, E; Myers, S; Petersson, N A; Sjogreen, B; Hauk, T; Wagoner, J

    2011-10-18

    The Source Physics Experiment (SPE) is planning a 1000 kg (TNT equivalent) shot (SPE2) at the Nevada National Security Site (NNSS) in a granite borehole at a depth (canister centroid) of 45 meters. This shot follows an earlier shot of 100 kg in the same borehole at a depth 60 m. Surrounding the shotpoint is an extensive array of seismic sensors arrayed in 5 radial lines extending out 2 km to the north and east and approximately 10-15 to the south and west. Prior to SPE1, simulations using a finite difference code and a 3D numerical model based on the geologic setting were conducted, which predicted higher amplitudes to the south and east in the alluvium of Yucca Flat along with significant energy on the transverse components caused by scattering within the 3D volume along with some contribution by topographic scattering. Observations from the SPE1 shot largely confirmed these predictions although the ratio of transverse energy relative to the vertical and radial components was in general larger than predicted. A new set of simulations has been conducted for the upcoming SPE2 shot. These include improvements to the velocity model based on SPE1 observations as well as new capabilities added to the simulation code. The most significant is the addition of a new source model within the finite difference code by using the predicted ground velocities from a hydrodynamic code (GEODYN) as driving condition on the boundaries of a cube embedded within WPP which provides a more sophisticated source modeling capability linked directly to source site materials (e.g. granite) and type and size of source. Two sets of SPE2 simulations are conducted, one with a GEODYN source and 3D complex media (no topography node spacing of 5 m) and one with a standard isotropic pre-defined time function (3D complex media with topography, node spacing of 5 m). Results were provided as time series at specific points corresponding to sensor locations for both translational (x,y,z) and rotational components. Estimates of spectral scaling for SPE2 are provided using a modified version of the Mueller-Murphy model. An estimate of expected aftershock probabilities were also provided, based on the methodology of Ford and Walter, [2010].

  19. A review of the role of colloids in the release and transport of radionuclides in the near and far field. Pt. 2

    International Nuclear Information System (INIS)

    Tipping, E.; Higgo, J.J.W.

    1992-01-01

    The role of colloids in the release/transport of radionuclides covers a range of scientific disciplines and there is a need for a comprehensive review that pulls together all the relevant research. A literature review has, therefore, been carried out and a bibliography prepared. Entries are in alphabetical (first author) order and abstracts are provided. This is part 2 of a three-part review. Part 1 reviews fundamental theory and DOE and NIREX funded work while Part 3 compares DOE and NIREX-funded work with the other published work and identifies gaps in the DOE and NIREX programmes. (Author)

  20. Humic substances in performance assessment of nuclear waste disposal: Actinide and iodine migration in the far-field. First technical progress report

    International Nuclear Information System (INIS)

    Buckau, G.

    2003-04-01

    The present project is one in a series of research activities supported by the European Commission on the role of humic substances for the long-term safety of nuclear waste disposal. These activities started in the mid eighties within the MIRAGE project (MIgration of RAdionuclides in the GEosphere) with the most recent project being ''Effects of humic substances on the migration of radionuclides: Complexation and transport of actinides (HUMICS)'' (FI4W-CT96-0028). The HUMICS project was conducted within the fourths framework of the European Commissions research program. It started January 1997 and had a duration of three years. The results of the HUMICS project can be found in three open technical progress reports and a final report [1-4]. In analogy with the HUMICS project, the present project makes use of annual technical progress reports where individual results are published as papers in the form of annexes. By this approach, results rapidly become available to interested parties in a compact form before their publication in various scientific journals and conference proceedings. Furthermore, some of the more preliminary and/or detailed results are not likely to appear in scientific journals and proceedings. The present project is conducted within the fifths framework of the European Commissions research program. It started November 2001 and has a duration of three years. The present report covers the first project year, i.e. November 2001 to September 2002. The project is divided into eight different work packages. These are (i) ''Critical assessment of experimental methods'', (ii) ''Generation and characterization of humic substances'', (iii) ''Radionuclide humate interaction data by designed system investigations'', (iv) ''Characterization of radionuclide humate complexes'', (v) ''Natural chemical analogue studies'', (vi) ''Radionuclide transport experiments'', (vii) ''Model development'', and (viii) ''Performance assessment''. Division of work into specified work packages sometimes is not straight forward. This is also reflected in the structure of the report. The executive summary report follows the project work package structure. The annexes focus on scientific results without reference to specific work packages. Following this approach, the reader can get an overview over the overall progress by the executive summary report. Detailed information on scientific results and the respective originators is found in the annexes. It should also be noted that some results presented in the executive summary report originate from presentations and communication within the project without being presented as an annex paper. Further information on such results can be obtained through the editor. (orig.)

  1. Far Field Sorption Data Bases for Performance Assessment of a High-Level Radioactive Waste Repository in an Undisturbed Opalinus Clay Host Rock

    Energy Technology Data Exchange (ETDEWEB)

    Bradburry, M.; Baeyens, B

    2003-08-01

    An Opalinus Clay formation in the Zuercher Weinland is under consideration by Nagra as a potential location for a high-level and long-Iived intermediate-level radioactive waste repository. Performance assessment studies will be performed for this site and the purpose of this report is to describe the procedures used to develop sorption data bases appropriate for an undisturbed Opalinus Clay host rock which are required for such safety analysis calculations. In tight, low water content argillaceous rock formations such as Opalinus Clay, there is uncertainty concerning the in situ pH/P{sub CO{sub 2}}. In order to take this intrinsic uncertainty into account porewater chemistries were calculated for a reference case, pH = 7.24, and for two other pH values, 6.3 and 7.8. Sorption data bases are given for the three cases. The basis for the sorption data bases is 'in-house' sorption measurements for Cs(I), Sr(II), Ni(II), Eu(III), Sn(IV), Se(IV), Th(IV) and I(-I) carried out on Opalinus Clay samples from Mont Terri (Canton Jura) since at the time the experiments were performed no core samples from the Benken borehole (Zuercher Weinland) were available. The Opalinus Clay at Mont Terri and Benken are part of the same geological formation . Despite having directly measured data for the above key radionuclides, some of the required distribution ratios (Rd) used to generate the sorption data bases still came from the open literature. An important part of this report is concerned with describing the procedures whereby these selected literature Rd values were modified so as to apply to the Benken Opalinus Clay mineralogy and groundwater chemistries calculated at the three pH values given above. The resulting Rd values were then further modified using so-called Lab{yields}Field transfer factors to produce sorption values which were appropriate to the in situ bulk rock for the selected range of water chemistry conditions. Finally, it is important to have some appreciation of the uncertainties associated with the selected Rd values in the sorption data bases. An attempt has been made in the report to move away from the unsatisfactory 'realistic/conservative' terminology and to develop a procedure for estimating uncertainty in a transparent and traceable manner. (author)

  2. Far-field triggering of foreshocks near the nucleation zone of the 5 September 2012 (MW 7.6) Nicoya Peninsula, Costa Rica earthquake

    Science.gov (United States)

    Walter, Jacob I.; Meng, Xiaofeng; Peng, Zhigang; Schwartz, Susan Y.; Newman, Andrew V.; Protti, Marino

    2015-12-01

    On 5 September 2012, a moment magnitude (MW) 7.6 earthquake occurred directly beneath the Nicoya Peninsula, an area with dense seismic and geodetic network coverage. The mainshock ruptured a portion of a previously identified locked patch that was recognized due to a decade-long effort to delineate the megathrust seismic and aseismic processes in this area. Here we conduct a comprehensive study of the seismicity prior to this event utilizing a matched-filter analysis that allows us to decrease the magnitude of catalog completeness by 1 unit. We observe a statistically significant increase in seismicity rate below the Nicoya Peninsula following the 27 August 2012 (MW 7.3) El Salvador earthquake (about 450 km to the northwest and 9 days prior to the Nicoya earthquake). Additionally, we identify a cluster of small-magnitude (earthquakes preceding the mainshock by about 35 min and within 15 km of its hypocenter. The immediate foreshock sequence occurred in the same area as those earthquakes triggered shortly after the El Salvador event; though it is not clear whether the effect of triggering from the El Salvador event persisted until the foreshock sequence given the uncertainties in seismicity rates from a relatively small number of earthquakes. If megathrust earthquakes at such distances can induce significant increases in seismicity during the days before another larger event, this sequence strengthens the need for real-time seismicity monitoring for large earthquake forecasting.

  3. Assessment of the computational uncertainty of temperature rise and SAR in the eyes and brain under far-field exposure from 1 to 10 GHz

    International Nuclear Information System (INIS)

    Laakso, Ilkka

    2009-01-01

    This paper presents finite-difference time-domain (FDTD) calculations of specific absorption rate (SAR) values in the head under plane-wave exposure from 1 to 10 GHz using a resolution of 0.5 mm in adult male and female voxel models. Temperature rise due to the power absorption is calculated by the bioheat equation using a multigrid method solver. The computational accuracy is investigated by repeating the calculations with resolutions of 1 mm and 2 mm and comparing the results. Cubically averaged 10 g SAR in the eyes and brain and eye-averaged SAR are calculated and compared to the corresponding temperature rise as well as the recommended limits for exposure. The results suggest that 2 mm resolution should only be used for frequencies smaller than 2.5 GHz, and 1 mm resolution only under 5 GHz. Morphological differences in models seemed to be an important cause of variation: differences in results between the two different models were usually larger than the computational error due to the grid resolution, and larger than the difference between the results for open and closed eyes. Limiting the incident plane-wave power density to smaller than 100 W m -2 was sufficient for ensuring that the temperature rise in the eyes and brain were less than 1 deg. C in the whole frequency range.

  4. Assessment of the computational uncertainty of temperature rise and SAR in the eyes and brain under far-field exposure from 1 to 10 GHz

    Science.gov (United States)

    Laakso, Ilkka

    2009-06-01

    This paper presents finite-difference time-domain (FDTD) calculations of specific absorption rate (SAR) values in the head under plane-wave exposure from 1 to 10 GHz using a resolution of 0.5 mm in adult male and female voxel models. Temperature rise due to the power absorption is calculated by the bioheat equation using a multigrid method solver. The computational accuracy is investigated by repeating the calculations with resolutions of 1 mm and 2 mm and comparing the results. Cubically averaged 10 g SAR in the eyes and brain and eye-averaged SAR are calculated and compared to the corresponding temperature rise as well as the recommended limits for exposure. The results suggest that 2 mm resolution should only be used for frequencies smaller than 2.5 GHz, and 1 mm resolution only under 5 GHz. Morphological differences in models seemed to be an important cause of variation: differences in results between the two different models were usually larger than the computational error due to the grid resolution, and larger than the difference between the results for open and closed eyes. Limiting the incident plane-wave power density to smaller than 100 W m-2 was sufficient for ensuring that the temperature rise in the eyes and brain were less than 1 °C in the whole frequency range.

  5. Assessment of the computational uncertainty of temperature rise and SAR in the eyes and brain under far-field exposure from 1 to 10 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, Ilkka [Department of Radio Science and Engineering, Helsinki University of Technology, Otakaari 5 A, 02150 Espoo (Finland)], E-mail: ilkka.laakso@tkk.fi

    2009-06-07

    This paper presents finite-difference time-domain (FDTD) calculations of specific absorption rate (SAR) values in the head under plane-wave exposure from 1 to 10 GHz using a resolution of 0.5 mm in adult male and female voxel models. Temperature rise due to the power absorption is calculated by the bioheat equation using a multigrid method solver. The computational accuracy is investigated by repeating the calculations with resolutions of 1 mm and 2 mm and comparing the results. Cubically averaged 10 g SAR in the eyes and brain and eye-averaged SAR are calculated and compared to the corresponding temperature rise as well as the recommended limits for exposure. The results suggest that 2 mm resolution should only be used for frequencies smaller than 2.5 GHz, and 1 mm resolution only under 5 GHz. Morphological differences in models seemed to be an important cause of variation: differences in results between the two different models were usually larger than the computational error due to the grid resolution, and larger than the difference between the results for open and closed eyes. Limiting the incident plane-wave power density to smaller than 100 W m{sup -2} was sufficient for ensuring that the temperature rise in the eyes and brain were less than 1 deg. C in the whole frequency range.

  6. Effects of near surface soil moisture profiles during evaporation on far-field ground-penetrating radar data: A numerical study

    KAUST Repository

    Moghadas, Davood; Jadoon, Khan; Vanderborght, Jan P.; Lambot, Sé bastien; Vereecken, Harry

    2013-01-01

    We theoretically investigated the effect of vapor flow on the drying front that develops in soils when water evaporates from the soil surface and on GPR data. The results suggest the integration of the full-wave GPR model with a coupled water, vapor

  7. Vertebrate Embryonic Cleavage Pattern Determination.

    Science.gov (United States)

    Hasley, Andrew; Chavez, Shawn; Danilchik, Michael; Wühr, Martin; Pelegri, Francisco

    2017-01-01

    The pattern of the earliest cell divisions in a vertebrate embryo lays the groundwork for later developmental events such as gastrulation, organogenesis, and overall body plan establishment. Understanding these early cleavage patterns and the mechanisms that create them is thus crucial for the study of vertebrate development. This chapter describes the early cleavage stages for species representing ray-finned fish, amphibians, birds, reptiles, mammals, and proto-vertebrate ascidians and summarizes current understanding of the mechanisms that govern these patterns. The nearly universal influence of cell shape on orientation and positioning of spindles and cleavage furrows and the mechanisms that mediate this influence are discussed. We discuss in particular models of aster and spindle centering and orientation in large embryonic blastomeres that rely on asymmetric internal pulling forces generated by the cleavage furrow for the previous cell cycle. Also explored are mechanisms that integrate cell division given the limited supply of cellular building blocks in the egg and several-fold changes of cell size during early development, as well as cytoskeletal specializations specific to early blastomeres including processes leading to blastomere cohesion. Finally, we discuss evolutionary conclusions beginning to emerge from the contemporary analysis of the phylogenetic distributions of cleavage patterns. In sum, this chapter seeks to summarize our current understanding of vertebrate early embryonic cleavage patterns and their control and evolution.

  8. Patterns of Software Development Process

    Directory of Open Access Journals (Sweden)

    Sandro Javier Bolaños Castro

    2011-12-01

    Full Text Available "Times New Roman","serif";mso-fareast-font-family:"Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA">This article presents a set of patterns that can be found to perform best practices in software processes that are directly related to the problem of implementing the activities of the process, the roles involved, the knowledge generated and the inputs and outputs belonging to the process. In this work, a definition of the architecture is encouraged by using different recurrent configurations that strengthen the process and yield efficient results for the development of a software project. The patterns presented constitute a catalog, which serves as a vocabulary for communication among project participants [1], [2], and also can be implemented through software tools, thus facilitating patterns implementation [3]. Additionally, a tool that can be obtained under GPL (General Public license is provided for this purpose

  9. Online Access Patterns and Students

    Directory of Open Access Journals (Sweden)

    Nasir Butrous

    2011-04-01

    Full Text Available The paper follows accessing patterns of five cohorts of postgraduate students enrolled in a core unit within a master of business administration (MBA program. The unit is designed to provide numerous opportunities for student participation in Discussion Boards using Blackboard technology. Discussion Boards create numerous opportunities for interaction amongst online learners to share and exchange their experiences, creating a sense of a virtual community. Relationships between accessing patterns for each week of the semester for each student are explored in relation to their performance using course statistics generated by the Blackboard technology. Close examination of the significant differences in access patterns to the course window and its components of communication, content, and student areas reveal middle of the semester (week 7 as the common critical point that differentiates high achieving students from low achieving students. Identifying critical points provides the faculty staff member an opportunity to introduce intervention strategies in order to improve the learning experience of all the students.

  10. Miliary pattern in neonatal pneumonia

    International Nuclear Information System (INIS)

    Flores, J.A.M.

    1988-01-01

    We have seen 10 newborn babies who developed respiratory distress and whose chest radiographs showed a miliary nodular pattern of disease. Of these infants only 3 had blood cultures that were positive for staphylococcus aureus. Of the remaining 7, 2 had conjunctivitis from which staphylococcus aureus was cultured, 4 had negative cultures and 1 did not have a blood culture done. All patients were diagnosed as having bacterial pneumonia and appeared to respond favourably to antibiotic therapy. The pulmonary abnormalities resolved. The children were clinically well in less than 3 weeks. The author suggests that the miliary pattern is one of the radiological patterns of neonatal pneumonia possibly produced by hematogenous bacterial dissemination. (orig.)

  11. Workflow patterns the definitive guide

    CERN Document Server

    Russell, Nick; ter Hofstede, Arthur H M

    2016-01-01

    The study of business processes has emerged as a highly effective approach to coordinating an organization's complex service- and knowledge-based activities. The growing field of business process management (BPM) focuses on methods and tools for designing, enacting, and analyzing business processes. This volume offers a definitive guide to the use of patterns, which synthesize the wide range of approaches to modeling business processes. It provides a unique and comprehensive introduction to the well-known workflow patterns collection -- recurrent, generic constructs describing common business process modeling and execution scenarios, presented in the form of problem-solution dialectics. The underlying principles of the patterns approach ensure that they are independent of any specific enabling technology, representational formalism, or modeling approach, and thus broadly applicable across the business process modeling and business process technology domains. The authors, drawing on extensive research done by...

  12. Towards pattern understanding-new technologies beyond pattern recognition

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, T

    1982-04-01

    The techniques employed in understanding-systems for pattern information are classified roughly under top-down and bottom-up techniques. These are outlined in the paper, and intellectual preparation for communications and information processing is briefly described. 1 ref.

  13. Spatiotemporal Wave Patterns: Information Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Mikhail Rabinovich; Lev Tsimring

    2006-01-20

    Pattern formation has traditionally been studied in non-equilibrium physics from the viewpoint of describing the basic structures and their interactions. While this is still an important area of research, the emphasis in the last few years has shifted towards analysis of specific properties of patterns in various complex media. For example, diverse and unexpected phenomena occur in neuro-like media that are characterized by highly non-trivial local dynamics. We carried out an active research program on analysis of spatio-temporal patterns in various physical systems (convection, oscillating fluid layer, soap film), as well as in neuro-like media, with an emphasis on informational aspects of the dynamics. Nonlinear nonequilibrium media and their discrete analogs have a unique ability to represent, memorize, and process the information contained in spatio-temporal patterns. Recent neurophysiological experiments demonstrated a certain universality of spatio-temporal representation of information by neural ensembles. Information processing is also revealed in the spatio-temporal dynamics of cellular patterns in nonequilibrium media. It is extremely important for many applications to study the informational aspects of these dynamics, including the origins and mechanisms of information generation, propagation and storage. Some of our results are: the discovery of self-organization of periodically oscillatory patterns in chaotic heterogeneous media; the analysis of the propagation of the information along a chaotic media as function of the entropy of the signal; the analysis of wave propagation in discrete non-equilibrium media with autocatalytic properties, which simulates the calcium dynamics in cellular membranes. Based on biological experiments we suggest the mechanism by which the spatial sensory information is transferred into the spatio-temporal code in the neural media. We also found a new mechanism of self-pinning in cellular structures and the related phenomenon

  14. Dark patterns in proxemic interactions

    DEFF Research Database (Denmark)

    Greenberg, Saul; Boring, Sebastian; Vermeulen, Jo

    2014-01-01

    to better facilitate seamless and natural interactions. To do so, both people and devices are tracked to determine their spatial relationships. While interest in proxemic interactions has increased over the last few years, it also has a dark side: knowledge of proxemics may (and likely will) be easily...... exploited to the detriment of the user. In this paper, we offer a critical perspective on proxemic interactions in the form of dark patterns: ways proxemic interactions can be misused. We discuss a series of these patterns and describe how they apply to these types of interactions. In addition, we identify...

  15. Separation vortices and pattern formation

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Bohr, Tomas; Schnipper, Teis

    2010-01-01

    In this paper examples are given of the importance of flow separation for fluid patterns at moderate Reynolds numbers—both in the stationary and in the time-dependent domain. In the case of circular hydraulic jumps, it has been shown recently that it is possible to generalise the Prandtl–Kármán–P...... results for the vortex patterns behind a flapping foil in a flowing soap film, which shows the interaction and competition between the vortices shed from the round leading edge (like the von Kármán vortex street) and those created at the sharp trailing edge....

  16. Patterns in Permutations and Words

    CERN Document Server

    Kitaev, Sergey

    2011-01-01

    There has been considerable interest recently in the subject of patterns in permutations and words, a new branch of combinatorics with its roots in the works of Rotem, Rogers, and Knuth in the 1970s. Consideration of the patterns in question has been extremely interesting from the combinatorial point of view, and it has proved to be a useful language in a variety of seemingly unrelated problems, including the theory of Kazhdan--Lusztig polynomials, singularities of Schubert varieties, interval orders, Chebyshev polynomials, models in statistical mechanics, and various sorting algorithms, inclu

  17. Turing patterns and biological explanation

    DEFF Research Database (Denmark)

    Serban, Maria

    2017-01-01

    , promoting theory exploration, and acting as constitutive parts of empirically adequate explanations of naturally occurring phenomena, such as biological pattern formation. Focusing on the roles that minimal model explanations play in science motivates the adoption of a broader diachronic view of scientific......Turing patterns are a class of minimal mathematical models that have been used to discover and conceptualize certain abstract features of early biological development. This paper examines a range of these minimal models in order to articulate and elaborate a philosophical analysis...

  18. Pattern formations and oscillatory phenomena

    CERN Document Server

    Kinoshita, Shuichi

    2013-01-01

    Patterns and their formations appear throughout nature, and are studied to analyze different problems in science and make predictions across a wide range of disciplines including biology, physics, mathematics, chemistry, material science, and nanoscience. With the emergence of nanoscience and the ability for researchers and scientists to study living systems at the biological level, pattern formation research has become even more essential. This book is an accessible first of its kind guide for scientists, researchers, engineers, and students who require a general introduction to thi

  19. Type-safe pattern combinators

    DEFF Research Database (Denmark)

    Rhiger, Morten

    2009-01-01

    Macros still haven't made their way into typed higher-order programming languages such as Haskell and Standard ML. Therefore, to extend the expressiveness of Haskell or Standard ML, one must express new linguistic features in terms of functions that fit within the static type systems of these lan...... of these languages. This is particularly challenging when introducing features that span across multiple types and that bind variables. We address this challenge by developing, in a step by step manner, mechanisms for encoding patterns and pattern matching in Haskell in a type-safe way....

  20. Interactive design of generic chemical patterns.

    Science.gov (United States)

    Schomburg, Karen T; Wetzer, Lars; Rarey, Matthias

    2013-07-01

    Every medicinal chemist has to create chemical patterns occasionally for querying databases, applying filters or describing functional groups. However, the representations of chemical patterns have been so far limited to languages with highly complex syntax, handicapping the application of patterns. Graphic pattern editors similar to chemical editors can facilitate the work with patterns. In this article, we review the interfaces of frequently used web search engines for chemical patterns. We take a look at pattern editing concepts of standalone chemical editors and finally present a completely new, unpublished graphical approach to pattern design, the SMARTSeditor. Copyright © 2013 Elsevier Ltd. All rights reserved.