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Sample records for mode matching technique

  1. Fiber cavities with integrated mode matching optics.

    Science.gov (United States)

    Gulati, Gurpreet Kaur; Takahashi, Hiroki; Podoliak, Nina; Horak, Peter; Keller, Matthias

    2017-07-17

    In fiber based Fabry-Pérot Cavities (FFPCs), limited spatial mode matching between the cavity mode and input/output modes has been the main hindrance for many applications. We have demonstrated a versatile mode matching method for FFPCs. Our novel design employs an assembly of a graded-index and large core multimode fiber directly spliced to a single mode fiber. This all-fiber assembly transforms the propagating mode of the single mode fiber to match with the mode of a FFPC. As a result, we have measured a mode matching of 90% for a cavity length of ~400 μm. This is a significant improvement compared to conventional FFPCs coupled with just a single mode fiber, especially at long cavity lengths. Adjusting the parameters of the assembly, the fundamental cavity mode can be matched with the mode of almost any single mode fiber, making this approach highly versatile and integrable.

  2. On a two-dimensional mode-matching technique for sound generation and transmission in axial-flow outlet guide vanes

    Science.gov (United States)

    Bouley, Simon; François, Benjamin; Roger, Michel; Posson, Hélène; Moreau, Stéphane

    2017-09-01

    The present work deals with the analytical modeling of two aspects of outlet guide vane aeroacoustics in axial-flow fan and compressor rotor-stator stages. The first addressed mechanism is the downstream transmission of rotor noise through the outlet guide vanes, the second one is the sound generation by the impingement of the rotor wakes on the vanes. The elementary prescribed excitation of the stator is an acoustic wave in the first case and a hydrodynamic gust in the second case. The solution for the response of the stator is derived using the same unified approach in both cases, within the scope of a linearized and compressible inviscid theory. It is provided by a mode-matching technique: modal expressions are written in the various sub-domains upstream and downstream of the stator as well as inside the inter-vane channels, and matched according to the conservation laws of fluid dynamics. This quite simple approach is uniformly valid in the whole range of subsonic Mach numbers and frequencies. It is presented for a two-dimensional rectilinear-cascade of zero-staggered flat-plate vanes and completed by the implementation of a Kutta condition. It is then validated in sound generation and transmission test cases by comparing with a previously reported model based on the Wiener-Hopf technique and with reference numerical simulations. Finally it is used to analyze the tonal rotor-stator interaction noise in a typical low-speed fan architecture. The interest of the mode-matching technique is that it could be easily transposed to a three-dimensional annular cascade in cylindrical coordinates in a future work. This makes it an attractive alternative to the classical strip-theory approach.

  3. Second Order Mode Selective Phase-Matching

    DEFF Research Database (Denmark)

    Lassen, Mikael Østergaard; Delaubert, Vincent; Bachor, Hans. A-

    2006-01-01

    We exploit second order (χ(2)) nonlinear optical phase matching for the selection of individual high order transverse modes. The ratio between the generated components can be adjusted continuously via changes in the phase-matching condition. ©2007 Optical Society of America......We exploit second order (χ(2)) nonlinear optical phase matching for the selection of individual high order transverse modes. The ratio between the generated components can be adjusted continuously via changes in the phase-matching condition. ©2007 Optical Society of America...

  4. Matching modes between HIRFL and CSR

    International Nuclear Information System (INIS)

    Tang, J.Y.; Li, H.H.; Yuan, Y.J.

    2001-01-01

    National key scientific project 'HIRFL-CSR Cooler Storage Ring' makes use of existing HIRFL as its pre-accelerator. In order to take the full capability of HIRFL, we have studied in detailed the matching modes between HIRFL and CSR. It is proposed to use two matching modes: direct matching between SFC (HIRFL injector cyclotron) and CSRm (CSR main ring), three-cascade matching of SFC, SSC (HIRFL main cyclotron) and CSRm. With these combinations, better beam transmission efficiency, better beam utilization efficiency of HIRFL-CSR accelerator complex and better operation efficiency of HIRFL can be obtained. In the first case, SSC can be used simultaneously in other purposes, either to accelerate medium energy heavy ions or to accelerate protons combined with another small cyclotron

  5. [Establishment of beta block matching technique].

    Science.gov (United States)

    Zhu, Fa-Ming; Lü, Qin-Feng; Zhang, Wei; Zhang, Hai-Qin; Fu, Qi-Hua; Yan, Li-Xing

    2005-10-01

    The purpose of this study was to establish beta block matching technique. DNA was extracted from whole blood by salting-out method, beta block matching was performed by PCR and GeneScan technique. The results showed that the length of fragments amplificated in 100 samples was different and the range of them was 91-197 bp. Amplification fragments could be divided into four regions: 91-93, 105-113, 125-139 and 177-197 bp respectively. 91 bp DNA fragments could be found in all of samples. The numbers of DNA fragments with different length have been shown high polymorphism and they focused on the range of seven to twenty four. In conclusion, the beta block matching technique is reliable and applicable to the selection of hematopoietic stem cell transplantation donors.

  6. Transverse Matching Techniques for the SNS Linac

    CERN Document Server

    Jeon Dong Oh; Danilov, Viatcheslav V

    2005-01-01

    It is crucial to minimize beam loss and machine activation by obtaining optimal transverse matching for a high-intensity linear accelerator such as the Spallation Neutron Source linac. For matching the Drift Tube Linac (DTL) to Coupled Cavity Linac (CCL), there are four wire-scanners installed in series in CCL module 1 as proposed by the author.* A series of measurements was conducted to minimize envelope breathing and the results are presented here. As an independent approach, Chu et al is developing an application based on another technique by estimating rms emittance using the wire scanner profile data.** For matching the Medium Energy Beam Transport Line to the DTL, a technique of minimizing rms emittance was used and emittance data show that tail is minimized as well.

  7. [Establishment of delta block matching technique].

    Science.gov (United States)

    Lü, Qin-Feng; Zhang, Wei; Zhu, Fa-Ming; Yan, Li-Xing

    2006-04-01

    To establish delta block HLA-matching technique, DNA was extracted from whole blood by salting-out method, delta block was amplified by polymerase chain reaction (PCR), and PCR product was detected by GeneScan. The results showed that delta block had polymorphism in 104 samples without sibship of the Han people from Zhejiang province. The range of DNA fragment length was 81-393 bp and could be divided into 4 groups: 81-118 bp, 140-175 bp, 217-301 bp, 340-393 bp. The numbers of DNA fragments were 6-32. It is concluded that the method of delta block matching is reliable and can be applied to select donors for the patients to be transplanted. It is the first time to get delta block data of the Han people in China.

  8. Techniques Used in String Matching for Network Security

    OpenAIRE

    Jamuna Bhandari

    2014-01-01

    String matching also known as pattern matching is one of primary concept for network security. In this area the effectiveness and efficiency of string matching algorithms is important for applications in network security such as network intrusion detection, virus detection, signature matching and web content filtering system. This paper presents brief review on some of string matching techniques used for network security.

  9. Hybrid silicon mode-locked laser with improved RF power by impedance matching

    Science.gov (United States)

    Tossoun, Bassem; Derickson, Dennis; Srinivasan, Sudharsanan; Bowers, John

    2015-02-01

    We design and discuss an impedance matching solution for a hybrid silicon mode-locked laser diode (MLLD) to improve peak optical power coming from the device. In order to develop an impedance matching solution, a thorough measurement and analysis of the MLLD as a function of bias on each of the laser segments was carried out. A passive component impedance matching network was designed at the operating frequency of 20 GHz to optimize RF power delivery to the laser. The hybrid silicon laser was packaged together in a module including the impedance matching circuit. The impedance matching design resulted in a 6 dB (electrical) improvement in the detected modulation spectrum power, as well as approximately a 10 dB phase noise improvement, from the MLLD. Also, looking ahead to possible future work, we discuss a Step Recovery Diode (SRD) driven impulse generator, which wave-shapes the RF drive to achieve efficient injection. This novel technique addresses the time varying impedance of the absorber as the optical pulse passes through it, to provide optimum optical pulse shaping.

  10. Template matching techniques in computer vision theory and practice

    CERN Document Server

    Brunelli, Roberto

    2009-01-01

    The detection and recognition of objects in images is a key research topic in the computer vision community.  Within this area, face recognition and interpretation has attracted increasing attention owing to the possibility of unveiling human perception mechanisms, and for the development of practical biometric systems. This book and the accompanying website, focus on template matching, a subset of object recognition techniques of wide applicability, which has proved to be particularly effective for face recognition applications. Using examples from face processing tasks throughout the book to illustrate more general object recognition approaches, Roberto Brunelli: examines the basics of digital image formation, highlighting points critical to the task of template matching;presents basic and  advanced template matching techniques, targeting grey-level images, shapes and point sets;discusses recent pattern classification paradigms from a template matching perspective;illustrates the development of a real fac...

  11. Technique to match mantle and para-aortic fields

    International Nuclear Information System (INIS)

    Lutz, W.R.; Larsen, R.D.

    1983-01-01

    A technique is described to match the mantle and para-aortic fields used in treatment of Hodgkin's disease, when the patient is treated alternately in supine and prone position. The approach is based on referencing the field edges to a point close to the vertebral column, where uncontrolled motion is minimal and where accurate matching is particularly important. Fiducial surface points are established in the simulation process to accomplish the objective. Dose distributions have been measured to study the combined effect of divergence differences, changes in body angulation and setup errors. Even with the most careful technique, the use of small cord blocks of 50% transmission is an advisable precaution for the posterior fields

  12. Index matching of TE and TM modes in organic multilayer waveguides

    Science.gov (United States)

    Thompson, Jonathan; Schmitzer, Heidrun; Wagner, Hans Peter

    We investigate transverse electric (TE) and magnetic (TM) mode propagation in organic multilayers consisting of aluminum quinoline (Alq3) and perylenetetracarboxylic dianhydride (PTCDA). In particular, we analyze two multilayer waveguides, Alq3-PTCDA-Alq3 and PTCDA-Alq3-PTCDA, engineered to give index matching according to modeling. The waveguides were grown on a glass substrate via organic molecular beam deposition. Fabry-Perot oscillations observed from reflection measurements were used to confirm the individual layer thicknesses. We were able to observe refractive index matching between TE0 and TE1, as well as TE2 and TE3 modes for the PTCDA-Alq3-PTCDA waveguide due to the light propagation through the top and bottom PTCDA layers, respectively. In addition, we were able to match TE1 and TM1, as well as TE3 and TM3 modes in the Alq3-PTCDA-Alq3 multilayer due to the birefringence of the PTCDA layer. Furthermore, we are able to create mode matching for a range of wavelengths due to the similar effective refractive index dispersion of different waveguide modes. The ability to phase match different waveguide modes opens a wide range of potential applications including polarization-insensitive propagation and mode switching by adding a thin magnetic metal film within the waveguide and applying an external magnetic field.

  13. Weed Identification Using An Automated Active Shape Matching (AASM) Technique

    DEFF Research Database (Denmark)

    Swain, K C; Nørremark, Michael; Jørgensen, R N

    2011-01-01

    on the concept of ‘active shape modelling’ to identify weed and crop plants based on their morphology. The automated active shape matching system (AASM) technique consisted of, i) a Pixelink camera ii) an LTI (Lehrstuhlfuer technische informatik) image processing library, iii) a laptop pc with the Linux OS. A 2......-leaf growth stage model for Solanum nigrum L. (nightshade) is generated from 32 segmented training images in Matlab software environment. Using the AASM algorithm, the leaf model was aligned and placed at the centre of the target plant and a model deformation process carried out. The parameters used......Weed identification and control is a challenge for intercultural operations in agriculture. As an alternative to chemical pest control, a smart weed identification technique followed by mechanical weed control system could be developed. The proposed smart identification technique works...

  14. Source Depth Estimation Using a Horizontal Array by Matched-Mode Processing in the Frequency-Wavenumber Domain

    Directory of Open Access Journals (Sweden)

    Nicolas Barbara

    2006-01-01

    Full Text Available In shallow water environments, matched-field processing (MFP and matched-mode processing (MMP are proven techniques for doing source localization. In these environments, the acoustic field propagates at long range as depth-dependent modes. Given a knowledge of the modes, it is possible to estimate source depth. In MMP, the pressure field is typically sampled over depth with a vertical line array (VLA in order to extract the mode amplitudes. In this paper, we focus on horizontal line arrays (HLA as they are generally more practical for at sea applications. Considering an impulsive low-frequency source (1–100 Hz in a shallow water environment (100–400 m, we propose an efficient method to estimate source depth by modal decomposition of the pressure field recorded on an HLA of sensors. Mode amplitudes are estimated using the frequency-wavenumber transform, which is the 2D Fourier transform of a time-distance section. We first study the robustness of the presented method against noise and against environmental mismatches on simulated data. Then, the method is applied both to at sea and laboratory data. We also show that the source depth estimation is drastically improved by incorporating the sign of the mode amplitudes.

  15. Analytical modelling of waveguide mode launchers for matched feed reflector systems

    DEFF Research Database (Denmark)

    Palvig, Michael Forum; Breinbjerg, Olav; Meincke, Peter

    2016-01-01

    Matched feed horns aim to cancel cross polarization generated in offset reflector systems. An analytical method for predicting the mode spectrum generated by inclusions in such horns, e.g. stubs and pins, is presented. The theory is based on the reciprocity theorem with the inclusions represented...

  16. Detailed phase matching characterization of inter-modal four-wave mixing in a two-mode fiber

    DEFF Research Database (Denmark)

    Friis, Søren Michael Mørk; Jung, Y.; Begleris, I.

    2016-01-01

    We experimentally characterize the phase matching properties of two inter-modal four-wave mixing processes in a graded index fiber guiding the LP01 and LP11 mode-groups.......We experimentally characterize the phase matching properties of two inter-modal four-wave mixing processes in a graded index fiber guiding the LP01 and LP11 mode-groups....

  17. An accelerated image matching technique for UAV orthoimage registration

    Science.gov (United States)

    Tsai, Chung-Hsien; Lin, Yu-Ching

    2017-06-01

    Using an Unmanned Aerial Vehicle (UAV) drone with an attached non-metric camera has become a popular low-cost approach for collecting geospatial data. A well-georeferenced orthoimage is a fundamental product for geomatics professionals. To achieve high positioning accuracy of orthoimages, precise sensor position and orientation data, or a number of ground control points (GCPs), are often required. Alternatively, image registration is a solution for improving the accuracy of a UAV orthoimage, as long as a historical reference image is available. This study proposes a registration scheme, including an Accelerated Binary Robust Invariant Scalable Keypoints (ABRISK) algorithm and spatial analysis of corresponding control points for image registration. To determine a match between two input images, feature descriptors from one image are compared with those from another image. A "Sorting Ring" is used to filter out uncorrected feature pairs as early as possible in the stage of matching feature points, to speed up the matching process. The results demonstrate that the proposed ABRISK approach outperforms the vector-based Scale Invariant Feature Transform (SIFT) approach where radiometric variations exist. ABRISK is 19.2 times and 312 times faster than SIFT for image sizes of 1000 × 1000 pixels and 4000 × 4000 pixels, respectively. ABRISK is 4.7 times faster than Binary Robust Invariant Scalable Keypoints (BRISK). Furthermore, the positional accuracy of the UAV orthoimage after applying the proposed image registration scheme is improved by an average of root mean square error (RMSE) of 2.58 m for six test orthoimages whose spatial resolutions vary from 6.7 cm to 10.7 cm.

  18. Linear stability of resistive MHD modes: axisymmetric toroidal computation of the outer region matching data

    International Nuclear Information System (INIS)

    Pletzer, A.; Bondeson, A.; Dewar, R.L.

    1993-11-01

    The quest to determine accurately the stability of tearing and resistive interchange modes in two-dimensional toroidal geometry led to the development of the PEST-3 code, which is based on solving the singular, zero-frequency ideal MHD equation in the plasma bulk and determining the outer data Δ', Γ' and A' needed to match the outer region solutions to those arising in the inner layers. No assumption regarding the aspect ratio, the number of rational surfaces or the pressure are made a priori. This approach is numerically less demanding than solving the full set of resistive equations, and has the major advantage of non-MHD theories of the non-ideal layers. Good convergence is ensured by the variational Galerkin scheme used to compute the outer matching data. To validate the code, we focus on the growth rate calculations of resistive kink modes which are reproduced in good agreement with those obtained by the full resistive MHD code MARS. (author) 11 figs., 27 refs

  19. A matching problem revisited for stability analysis of resistive wall modes in flowing plasmas

    International Nuclear Information System (INIS)

    Shiraishi, J.; Tokuda, S.; Aiba, N.

    2010-01-01

    The classical matching problem for magnetohydrodynamic stability analysis is revisited to study effects of the plasma flow on the resistive wall modes (RWMs). The Newcomb equation, which describes the marginal states and governs the regions except for the resonant surface, is generalized to analyze the stability of flowing plasmas. When there exists no flow, the singular point of the Newcomb equation and the resonant surface degenerate into the rational surface. The location of the rational surface is prescribed by the equilibrium, hence the inner layer, which must contain the resonant surface, can be set a priori. When the flow exists, the singular point of the Newcomb equation splits in two due to the Doppler shift. Additionally, the resonant surface deviates from the singular points and the rational surface if the resonant eigenmode has a real frequency. Since the location of the resonant surface depends on the unknown real frequency, it can be determined only a posteriori. Hence the classical asymptotic matching method cannot be applied. This paper shows that a new matching method that generalizes the asymptotic one to use the inner layer with finite width works well for the stability analysis of flowing plasmas. If the real frequency is limited in a certain range such as the RWM case, the resonance occurs somewhere in the finite region around the singular points, hence the inner layer with finite width can capture the resonant surface.

  20. Analysis of Waveguide Devices Involving Lateral and Transverse Perfect Magnetic Wall Boundary Conditions by the Mode-Matching Method

    Science.gov (United States)

    Polo-López, Lucas; Ruiz-Cruz, Jorge A.; Montejo-Garai, José R.; Rebollar, Jesús M.

    2017-09-01

    This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition is used in electromagnetic solvers very commonly when the device under analysis has physical symmetry, in order to speed up the computation time. This paper is focused on extending its use in problems having this type of boundary condition in the lateral and transverse walls of the waveguides involved in the problem. The presented formulation, based on the mode-matching method, will be applied to classical waveguide devices, but also to address radiating problems with a novel formulation. Different applications will be targeted, and the simulation results will be compared with those obtained by other numerical techniques (based on different solvers), validating the presented approach as another suitable tool for computer-aided design.

  1. Naturally Phase-Matched Second-Harmonic Generation in a Whispering-Gallery-Mode Resonator

    DEFF Research Database (Denmark)

    Fürst, J. U.; Strekalov, D.V.; Elser, D.

    2010-01-01

    We demonstrate for the first time natural phase matching for optical frequency doubling in a high-Q whispering-gallery-mode resonator made of lithium niobate. A conversion efficiency of 9% is achieved at 30  μW in-coupled continuous wave pump power. The observed saturation pump power of 3.2 m......W is almost 2 orders of magnitude lower than the state-of-the-art value. This suggests an application of our frequency doubler as a source of nonclassical light requiring only a low-power pump, which easily can be quantum noise limited. Our theoretical analysis of the three-wave mixing in a whispering-gallery...

  2. Alarm handling systems and techniques developed to match operator tasks

    International Nuclear Information System (INIS)

    Bye, A.; Moum, B.R.

    1997-01-01

    This paper covers alarm handling methods and techniques explored at the Halden Project, and describes current status on the research activities on alarm systems. Alarm systems are often designed by application of a bottom-up strategy, generating alarms at component level. If no structuring of the alarms is applied, this may result in alarm avalanches in major plant disturbances, causing cognitive overload of the operator. An alarm structuring module should be designed using a top-down approach, analysing operator's tasks, plant states, events and disturbances. One of the operator's main tasks during plant disturbances is status identification, including determination of plant status and detection of plant anomalies. The main support of this is provided through the alarm systems, the process formats, the trends and possible diagnosis systems. The alarm system should both physically and conceptually be integrated with all these systems. 9 refs, 5 figs

  3. Two-dimensional gel electrophoresis image registration using block-matching techniques and deformation models.

    Science.gov (United States)

    Rodriguez, Alvaro; Fernandez-Lozano, Carlos; Dorado, Julian; Rabuñal, Juan R

    2014-06-01

    Block-matching techniques have been widely used in the task of estimating displacement in medical images, and they represent the best approach in scenes with deformable structures such as tissues, fluids, and gels. In this article, a new iterative block-matching technique-based on successive deformation, search, fitting, filtering, and interpolation stages-is proposed to measure elastic displacements in two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) images. The proposed technique uses different deformation models in the task of correlating proteins in real 2D electrophoresis gel images, obtaining an accuracy of 96.6% and improving the results obtained with other techniques. This technique represents a general solution, being easy to adapt to different 2D deformable cases and providing an experimental reference for block-matching algorithms. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Mortality, Hospitalization, and Technique Failure in Daily Home Hemodialysis and Matched Peritoneal Dialysis Patients: A Matched Cohort Study.

    Science.gov (United States)

    Weinhandl, Eric D; Gilbertson, David T; Collins, Allan J

    2016-01-01

    Use of home dialysis is growing in the United States, but few direct comparisons of major clinical outcomes on daily home hemodialysis (HHD) versus peritoneal dialysis (PD) exist. Matched cohort study. We matched 4,201 new HHD patients in 2007 to 2010 with 4,201 new PD patients from the US Renal Data System database. Daily HHD versus PD. Relative mortality, hospitalization, and technique failure. Mean time from end-stage renal disease onset to home dialysis therapy initiation was 44.6 months for HHD and 44.3 months for PD patients. In intention-to-treat analysis, HHD was associated with 20% lower risk for all-cause mortality (HR, 0.80; 95% CI, 0.73-0.87), 8% lower risk for all-cause hospitalization (HR, 0.92; 95% CI, 0.89-0.95), and 37% lower risk for technique failure (HR, 0.63; 95% CI, 0.58-0.68), all relative to PD. In the subset of 1,368 patients who initiated home dialysis therapy within 6 months of end-stage renal disease onset, HHD was associated with similar risk for all-cause mortality (HR, 0.95; 95% CI, 0.80-1.13), similar risk for all-cause hospitalization (HR, 0.96; 95% CI, 0.88-1.05), and 30% lower risk for technique failure (HR, 0.70; 95% CI, 0.60-0.82). Regarding hospitalization, risk comparisons favored HHD for cardiovascular disease and dialysis access infection and PD for bloodstream infection. Matching unlikely to reduce confounding attributable to unmeasured factors, including residual kidney function; lack of data regarding dialysis frequency, duration, and dose in daily HHD patients and frequency and solution in PD patients; diagnosis codes used to classify admissions. These data suggest that relative to PD, daily HHD is associated with decreased mortality, hospitalization, and technique failure. However, risks for mortality and hospitalization were similar with these modalities in new dialysis patients. The interaction between modality and end-stage renal disease duration at home dialysis therapy initiation should be investigated further

  5. Analysis and quantification of arterial wall motion from B-mode ultrasound images - comparison of block-matching and optical flow.

    Science.gov (United States)

    Stoitsis, J; Golemati, S; Dimopoulos, A; Nikita, K

    2005-01-01

    Motion of the carotid atheromatous plaque may be responsible for plaque rupture and cerebrovascular symptoms. B-mode ultrasound allows non-invasive recording of arterial wall and plaque motion. Our aim was to analyze quantitatively patterns of arterial wall motion with different techniques. Temporal sequences of digitized B-mode ultrasound images of the carotid arteries of 10 young healthy subjects were interrogated. Arterial wall motion was analyzed using: a/ block-matching, and b/ optical flow. The motion of selected regions of the luminal surface of the arterial wall was estimated using region tracking and block-matching. The motion of areas of the arterial wall was estimated using optical flow. Waveforms showing radial and axial displacements, as well as radial and axial velocities were produced for the selected ROIs using both techniques. Both techniques produced waveforms with peaks, corresponding to cardiac cycle events, that occurred at similar time points. To study the similarity of the waveforms obtained from the two techniques, a cross-correlation coefficient was calculated. Cross-correlation coefficients were 0.72..0.22 and 0.70..0.19 for displacements and velocities, respectively, in the radial direction. In the axial direction, the coefficients were 0.32..0.39 and 0.24..0.22 for displacements and velocities, respectively. On the basis of this relative comparison of methods, we conclude that significant observations can be made for each motion analysis technique in terms of characterization of the mechanical properties of the tissue.

  6. New modes of particle accelerations techniques and sources. Formal report

    Energy Technology Data Exchange (ETDEWEB)

    Parsa, Z. [ed.

    1996-12-31

    This Report includes copies of transparencies and notes from the presentations made at the Symposium on New Modes of Particle Accelerations - Techniques and Sources, August 19-23, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report.

  7. New modes of particle accelerations techniques and sources. Formal report

    International Nuclear Information System (INIS)

    Parsa, Z.

    1996-01-01

    This Report includes copies of transparencies and notes from the presentations made at the Symposium on New Modes of Particle Accelerations - Techniques and Sources, August 19-23, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report

  8. The exact rogue wave recurrence in the NLS periodic setting via matched asymptotic expansions, for 1 and 2 unstable modes

    Science.gov (United States)

    Grinevich, P. G.; Santini, P. M.

    2018-04-01

    The focusing Nonlinear Schrödinger (NLS) equation is the simplest universal model describing the modulation instability (MI) of quasi monochromatic waves in weakly nonlinear media, the main physical mechanism for the generation of rogue (anomalous) waves (RWs) in Nature. In this paper we investigate the x-periodic Cauchy problem for NLS for a generic periodic initial perturbation of the unstable constant background solution, in the case of N = 1 , 2 unstable modes. We use matched asymptotic expansion techniques to show that the solution of this problem describes an exact deterministic alternate recurrence of linear and nonlinear stages of MI, and that the nonlinear RW stages are described by the N-breather solution of Akhmediev type, whose parameters, different at each RW appearance, are always given in terms of the initial data through elementary functions. This paper is motivated by a preceding work of the authors in which a different approach, the finite gap method, was used to investigate periodic Cauchy problems giving rise to RW recurrence.

  9. An analysis of matching cognitive-behavior therapy techniques to learning styles.

    Science.gov (United States)

    van Doorn, Karlijn; McManus, Freda; Yiend, Jenny

    2012-12-01

    To optimize the effectiveness of cognitive-behavior therapy (CBT) for each individual patient, it is important to discern whether different intervention techniques may be differentially effective. One factor influencing the differential effectiveness of CBT intervention techniques may be the patient's preferred learning style, and whether this is 'matched' to the intervention. The current study uses a retrospective analysis to examine whether the impact of two common CBT interventions (thought records and behavioral experiments) is greater when the intervention is either matched or mismatched to the individual's learning style. Results from this study give some indication that greater belief change is achieved when the intervention technique is matched to participants' learning style, than when intervention techniques are mismatched to learning style. Conclusions are limited by the retrospective nature of the analysis and the limited dose of the intervention in non-clinical participants. Results suggest that further investigation of the impact of matching the patient's learning style to CBT intervention techniques is warranted, using clinical samples with higher dose interventions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Electron/photon matched field technique for treatment of orbital disease

    International Nuclear Information System (INIS)

    Arthur, Douglas W.; Zwicker, Robert D.; Garmon, Pamela W.; Huang, David T.; Schmidt-Ullrich, Rupert K.

    1997-01-01

    Purpose: A number of approaches have been described in the literature for irradiation of malignant and benign diseases of the orbit. Techniques described to date do not deliver a homogeneous dose to the orbital contents while sparing the cornea and lens of excessive dose. This is a result of the geometry encountered in this region and the fact that the target volume, which includes the periorbital and retroorbital tissues but excludes the cornea, anterior chamber, and lens, cannot be readily accommodated by photon beams alone. To improve the dose distribution for these treatments, we have developed a technique that combines a low-energy electron field carefully matched with modified photon fields to achieve acceptable dose coverage and uniformity. Methods and Materials: An anterior electron field and a lateral photon field setup is used to encompass the target volume. Modification of these fields permits accurate matching as well as conformation of the dose distribution to the orbit. A flat-surfaced wax compensator assures uniform electron penetration across the field, and a sunken lead alloy eye block prevents excessive dose to the central structures of the anterior segment. The anterior edge of the photon field is modified by broadening the penumbra using a form of pseudodynamic collimation. Direct measurements using film and ion chamber dosimetry were used to study the characteristics of the fall-off region of the electron field and the penumbra of the photon fields. >From the data collected, the technique for accurate field matching and dose uniformity was generated. Results: The isodose curves produced with this treatment technique demonstrate homogeneous dose coverage of the orbit, including the paralenticular region, and sufficient dose sparing of the anterior segment. The posterior lens accumulates less than 40% of the prescribed dose, and the lateral aspect of the lens receives less than 30%. A dose variation in the match region of ±12% is confronted when

  11. Optimal Control Techniques for ResistiveWall Modes in Tokamaks

    Science.gov (United States)

    Clement, Mitchell Dobbs Pearson

    Tokamaks can excite kink modes that can lock or nearly lock to the vacuum vessel wall, and whose rotation frequencies and growth rates vary in time but are generally inversely proportional to the magnetic flux diffusion time of the vacuum vessel wall. This magnetohydrodynamic (MHD) instability is pressure limiting in tokamaks and is called the Resistive Wall Mode (RWM). Future tokamaks that are expected to operate as fusion reactors will be required to maximize plasma pressure in order to maximize fusion performance. The DIII-D tokamak is equipped with electromagnetic control coils, both inside and outside of its vacuum vessel, which create magnetic fields that are small by comparison to the machine's equilibrium field but are able to dynamically counteract the RWM. Presently for RWM feedback, DIII-D uses its interior control coils using a classical proportional gain only controller to achieve high plasma pressure. Future advanced tokamak designs will not likely have the luxury of interior control coils and a proportional gain algorithm is not expected to be effective with external control coils. The computer code VALEN was designed to calculate the performance of an MHD feedback control system in an arbitrary geometry. VALEN models the perturbed magnetic field from a single MHD instability and its interaction with surrounding conducting structures using a finite element approach. A linear quadratic gaussian (LQG) control, or H 2 optimal control, algorithm based on the VALEN model for RWM feedback was developed for use with DIII-D's external control coil set. The algorithm is implemented on a platform that combines a graphics processing unit (GPU) for real-time control computation with low latency digital input/output control hardware and operates in parallel with the DIII-D Plasma Control System (PCS). Simulations and experiments showed that modern control techniques performed better, using 77% less current, than classical techniques when using coils external to

  12. ISOLATED SPEECH RECOGNITION SYSTEM FOR TAMIL LANGUAGE USING STATISTICAL PATTERN MATCHING AND MACHINE LEARNING TECHNIQUES

    Directory of Open Access Journals (Sweden)

    VIMALA C.

    2015-05-01

    Full Text Available In recent years, speech technology has become a vital part of our daily lives. Various techniques have been proposed for developing Automatic Speech Recognition (ASR system and have achieved great success in many applications. Among them, Template Matching techniques like Dynamic Time Warping (DTW, Statistical Pattern Matching techniques such as Hidden Markov Model (HMM and Gaussian Mixture Models (GMM, Machine Learning techniques such as Neural Networks (NN, Support Vector Machine (SVM, and Decision Trees (DT are most popular. The main objective of this paper is to design and develop a speaker-independent isolated speech recognition system for Tamil language using the above speech recognition techniques. The background of ASR system, the steps involved in ASR, merits and demerits of the conventional and machine learning algorithms and the observations made based on the experiments are presented in this paper. For the above developed system, highest word recognition accuracy is achieved with HMM technique. It offered 100% accuracy during training process and 97.92% for testing process.

  13. Technique to Match Gingival Shade when Using Pink Ceramics for Anterior Fixed Implant Prostheses.

    Science.gov (United States)

    Papaspyridakos, Panos; Amin, Sarah; El-Rafie, Khaled; Weber, Hans-Peter

    2018-03-01

    Use of pink gingival ceramics can reduce the necessity for extensive surgical procedures attempting to restore missing soft and hard tissues in the maxillary esthetic zone. Selecting the appropriate shade for pink porcelain poses a challenge, especially when the patient presents with a high smile line. This paper describes a simple and effective technique to facilitate shade selection for gingival ceramics to match the patient's existing gingival shade. © 2016 by the American College of Prosthodontists.

  14. Matching of the coupler cavity to travelling wave structures at any operating mode

    International Nuclear Information System (INIS)

    Chanudet, M.

    1993-06-01

    For the realization of an accelerating travelling wave structure, it is important to adjust the coupler so that the rf power arriving through a rectangular waveguide is coupled to the structure without reflection from the input aperture of the first cavity, the coupler cavity. The problem consists in carefully determining the dimensions of the coupling aperture. A method is proposed to measure this coupling in the case of monoperiodic forward and backward wave structures. The theory is based on the possibility of representing the properties of electromagnetic modes in periodic structures by coupled RLC circuits. The study of current I and voltage V versus frequency ω allows the simulation of H and E fields, respectively, for the different modes appearing in a travelling wave structure. (K.A.) 4 refs.; 14 figs

  15. Measurement of velocity field in pipe with classic twisted tape using matching refractive index technique

    International Nuclear Information System (INIS)

    Song, Min Seop; Park, So Hyun; Kim, Eung Soo

    2014-01-01

    Many researchers conducted experiments and numerical simulations to measure or predict a Nusselt number or a friction factor in a pipe with a twisted tape while some other studies focused on the heat transfer performance enhancement using various twisted tape configurations. However, since the optical access to the inner space of a pipe with a twisted tape was limited, the detailed flow field data were not obtainable so far. Thus, researchers mainly relied on the numerical simulations to obtain the data of the flow field. In this study, a 3D printing technique was used to manufacture a transparent test section for optical access. And also, a noble refractive index matching technique was used to eliminate optical distortion. This two combined techniques enabled to measure the velocity profile with Particle Image Velocimetry (PIV). The measured velocity field data can be used either to understand the fundamental flow characteristics around a twisted tape or to validate turbulence models in Computational Fluid Dynamics (CFD). In this study, the flow field in the test-section was measured for various flow conditions and it was finally compared with numerically calculated data. Velocity fields in a pipe with a classic twisted tape was measured using a particle image velocimetry (PIV) system. To obtain undistorted particle images, a noble optical technique, refractive index matching, was used and it was proved that high-quality image can be obtained from this experimental equipment. The velocity data from the PIV was compared with the CFD simulations

  16. Template Matching of Colored Image Based on Quaternion Fourier Transform and Image Pyramid Techniques

    Directory of Open Access Journals (Sweden)

    M.I. KHALIL

    2016-04-01

    Full Text Available Template matching method is one of the most significant object recognition techniques and it has many applications in the field of digital signal processing and image processing and it is the base for object tracking in computer vision field. The traditional template matching by correlation is performed between gray template image w and the candidate gray image f where the template’s position is to be determined in the candidate image. This task can be achieved by measuring the similarity between the template image and the candidate image to identify and localize the existence of object instances within an image. When applying this method to colored image, the image must be converted to a gray one or decomposed to its RGB components to be processed separately. The current paper aims to apply the template matching technique to colored images via generating the quaternion Fourier transforms of both the template and candidate colored image and hence performing the cross-correlation between those transforms. Moreover, this approach is improved by representing both the image and template as pyramid multi-resolution format to reduce the time of processing. The proposed algorithm is implemented and applied to different images and templates using Matlab functions.

  17. 3D modelling of trompe l'oeil decorated vaults using dense matching techniques

    Science.gov (United States)

    Chiabrando, F.; Lingua, A.; Noardo, F.; Spano, A.

    2014-05-01

    Dense matching techniques, implemented in many commercial and open source software, are useful instruments for carrying out a rapid and detailed analysis of complex objects, including various types of details and surfaces. For this reason these tools were tested in the metric survey of a frescoed ceiling in the hall of honour of a baroque building. The surfaces are covered with trompe-l'oeil paintings which theoretically can give a very good texture to automatic matching algorithms but in this case problems arise when attempting to reconstruct the correct geometry: in fact, in correspondence with the main architectonic painted details, the models present some irregularities, unexpectedly coherent with the painted drawing. The photogrammetric models have been compared with data deriving from a LIDAR survey of the same object, to evaluate the entity of this blunder: some profiles of selected sections have been extracted, verifying the different behaviours of the software tools.

  18. Muscular Contraction Mode Differently Affects Autonomic Control During Heart Rate Matched Exercise

    Directory of Open Access Journals (Sweden)

    Matthias eWeippert

    2015-05-01

    Full Text Available The precise contributions of afferent feedback to cardiovascular and respiratory responses to exercise are still unclear. Aim of this crossover study was to assess whether and how autonomic cardiovascular and respiratory control differed in response to dynamic (DYN and isometric contractions (ISO at a similar, low heart rate (HR level. Therefore, 22 healthy males (26.7 ± 3.6 yrs performed two kinds of voluntary exercises at similar HR: ISO and DYN of the right quadriceps femoris muscle. Although HR was eqivalent (82 ± 8 bpm for DYN and ISO, respectively, rating of exertion, blood pressures, and rate pressure product were higher, whereas breathing frequency, minute ventilation, oxygen uptake and carbon dioxide output were significantly lower during ISO. Tidal volume, end-tidal partial pressures of O2 and CO2, respiratory exchange ratio and capillary blood lactate concentration were comparable between both contraction modes. Heart rate variability (HRV indicators, SDNN, HF-Power and LF-Power, representing both vagal and sympathetic influences, were significantly higher during ISO. Sample entropy, a nonlinear measure of HRV was also significantly affected by contraction mode. It can be concluded that, despite the same net effect on HR, the quality of cardiovascular control during low intensity exercise is significantly different between DYN and ISO. HRV analysis indicated a sympatho-vagal coactivation during ISO. Whether mechanoreceptor feedback alone, a change in central command, or the interaction of both mechanisms is the main contributor of the distinct autonomic responses to the different exercise modes remains to be elucidated.

  19. Analysis of strictly bound modes in photonic crystal fibers by use of a source-model technique.

    Science.gov (United States)

    Hochman, Amit; Leviatan, Yehuda

    2004-06-01

    We describe a source-model technique for the analysis of the strictly bound modes propagating in photonic crystal fibers that have a finite photonic bandgap crystal cladding and are surrounded by an air jacket. In this model the field is simulated by a superposition of fields of fictitious electric and magnetic current filaments, suitably placed near the media interfaces of the fiber. A simple point-matching procedure is subsequently used to enforce the continuity conditions across the interfaces, leading to a homogeneous matrix equation. Nontrivial solutions to this equation yield the mode field patterns and propagation constants. As an example, we analyze a hollow-core photonic crystal fiber. Symmetry characteristics of the modes are discussed and exploited to reduce the computational burden.

  20. A critical interpersonal distance switches between two coordination modes in kendo matches.

    Science.gov (United States)

    Okumura, Motoki; Kijima, Akifumi; Kadota, Koji; Yokoyama, Keiko; Suzuki, Hiroo; Yamamoto, Yuji

    2012-01-01

    In many competitive sports, players need to quickly and continuously execute movements that co-adapt to various movements executed by their opponents and physical objects. In a martial art such as kendo, players must be able to skillfully change interpersonal distance in order to win. However, very little information about the task and expertise properties of the maneuvers affecting interpersonal distance is available. This study investigated behavioral dynamics underlying opponent tasks by analyzing changes in interpersonal distance made by expert players in kendo matches. Analysis of preferred interpersonal distances indicated that players tended to step toward and away from their opponents based on two distances. The most preferred distance enabled the players to execute both striking and defensive movements immediately. The relative phase analysis of the velocities at which players executed steps toward and away revealed that players developed anti-phase synchronizations at near distances to maintain safe distances from their opponents. Alternatively, players shifted to in-phase synchronization to approach their opponents from far distances. This abrupt phase-transition phenomenon constitutes a characteristic bifurcation dynamics that regularly and instantaneously occurs between in- and anti-phase synchronizations at a critical interpersonal distance. These dynamics are profoundly affected by the task constraints of kendo and the physical constraints of the players. Thus, the current study identifies the clear behavioral dynamics that emerge in a sport setting.

  1. Datafish Multiphase Data Mining Technique to Match Multiple Mutually Inclusive Independent Variables in Large PACS Databases.

    Science.gov (United States)

    Kelley, Brendan P; Klochko, Chad; Halabi, Safwan; Siegal, Daniel

    2016-06-01

    Retrospective data mining has tremendous potential in research but is time and labor intensive. Current data mining software contains many advanced search features but is limited in its ability to identify patients who meet multiple complex independent search criteria. Simple keyword and Boolean search techniques are ineffective when more complex searches are required, or when a search for multiple mutually inclusive variables becomes important. This is particularly true when trying to identify patients with a set of specific radiologic findings or proximity in time across multiple different imaging modalities. Another challenge that arises in retrospective data mining is that much variation still exists in how image findings are described in radiology reports. We present an algorithmic approach to solve this problem and describe a specific use case scenario in which we applied our technique to a real-world data set in order to identify patients who matched several independent variables in our institution's picture archiving and communication systems (PACS) database.

  2. Classification of normal and arrhythmic ECG using wavelet transform based template-matching technique.

    Science.gov (United States)

    Hassan, Wajahat; Saleem, Saqib; Habib, Aamir

    2017-06-01

    To propose a wavelet-based template matching technique to extract features for automatic classification of electrocardiogram signals of normal and arrhythmic individuals. The study was conducted from December 2014 to December 2015 at the Department of Electrical Engineering, Institute of Space Technology, Islamabad, Pakistan. Electrocardiogram signals analysed in this study were taken from the freely available database www.physionet.org. The data for normal subjects was taken from the Massachusetts Institute of Technology-Beth Israel Hospital's normal sinus rhythm database and data for diseased subjects was taken from the arrhythmia database. Of the 30 subjects, there were 15(50%) normal and 15(50%) diseased subjects. The group-averaged phase difference indices of arrhythmic subjects were significantly larger than that of normal individuals (p<0.05) within the frequency range of 0.9-1.1 Hz. Moreover, the scatter plot between the phase difference index and magnitude of wavelet cross-spectrum for frequency range of 0.9-1.1 Hz demonstrated a satisfactory delineation between normal and arrhythmic individuals. Wavelet decomposition-based template matching technique achieved satisfactory delineation of normal and arrhythmic electrocardiogram dynamics.

  3. A computer-video aided time motion analysis technique for match analysis.

    Science.gov (United States)

    Ali, A; Farrally, M

    1991-03-01

    The purpose of this study was to find out suitable methods for obtaining objective data on the time spent by players of different positions during walking, jogging, cruising, sprinting and standing still during match play activities. Computer programs and filming analyses with a simple notation system based upon symbolic representations of movements have been devised for analysis of individual players' behaviour. A technique was devised and employed with a small group of university players, aged 19-21 years of age. The subjects were filmed in several matches, and the video recordings were analysed using a microcomputer. The ratio of the time spent for the players were 56% walking, 30% jogging, 4% cruising, 3% sprinting and 7% standing still. ANOVA revealed that there are significant differences among the players for different positions on the field, for example the time spent on walking, jogging and standing still differed (P less than 0.05) among attackers, defenders and midfielders. A new method has been developed to obtain reliable information about the players' movement and performance in the game. The Authors believe that there should be further studies carried out involving more teams at different levels of performance to substantiate these preliminary findings.

  4. A Block-matching based technique for the analysis of 2D gel images.

    Science.gov (United States)

    Freire, Ana; Seoane, José A; Rodríguez, Alvaro; Ruiz-Romero, Cristina; López-Campos, Guillermo; Dorado, Julián

    2010-01-01

    Research at protein level is a useful practice in personalized medicine. More specifically, 2D gel images obtained after electrophoresis process can lead to an accurate diagnosis. Several computational approaches try to help the clinicians to establish the correspondence between pairs of proteins of multiple 2D gel images. Most of them perform the alignment of a patient image referred to a reference image. In this work, an approach based on block-matching techniques is developed. Its main characteristic is that it does not need to perform the whole alignment between two images considering each protein separately. A comparison with other published methods is presented. It can be concluded that this method works over broad range of proteomic images, although they have a high level of difficulty.

  5. The comparison of Co-60 and 4MV photons matching dosimetry during half-beam technique

    International Nuclear Information System (INIS)

    Cakir, Aydin; Bilge, Hatice; Dadasbilge, Alpar; Kuecuecuek, Halil; Okutan, Murat; Merdan Fayda, Emre

    2005-01-01

    In this phantom study, we tried to compare matching dosimetry differences between half-blocking of Co-60 and asymmetric collimation of the 4MV photons during craniospinal irradiation. The dose distributions are compared and discussed. Firstly, some gaps with different sizes are left between cranial and spinal field borders. Secondly, the fields are overlapped in the same sizes. We irradiate the films located in water-equivalent solid phantoms with Co-60 and 4MV photon beams. This study indicates that the field placement errors in +/- 1mm are acceptable for both Co-60 and 4MV photon energies during craniospinal irradiation with half-beam block technique. Within these limits the dose variations are specified in +/- 5%. However, the setup errors that are more than 1mm are unacceptable for both asymmetric collimation of 4MV photon and half-blocking of Co-60

  6. An Improved Map-Matching Technique Based on the Fréchet Distance Approach for Pedestrian Navigation Services

    Directory of Open Access Journals (Sweden)

    Yoonsik Bang

    2016-10-01

    Full Text Available Wearable and smartphone technology innovations have propelled the growth of Pedestrian Navigation Services (PNS. PNS need a map-matching process to project a user’s locations onto maps. Many map-matching techniques have been developed for vehicle navigation services. These techniques are inappropriate for PNS because pedestrians move, stop, and turn in different ways compared to vehicles. In addition, the base map data for pedestrians are more complicated than for vehicles. This article proposes a new map-matching method for locating Global Positioning System (GPS trajectories of pedestrians onto road network datasets. The theory underlying this approach is based on the Fréchet distance, one of the measures of geometric similarity between two curves. The Fréchet distance approach can provide reasonable matching results because two linear trajectories are parameterized with the time variable. Then we improved the method to be adaptive to the positional error of the GPS signal. We used an adaptation coefficient to adjust the search range for every input signal, based on the assumption of auto-correlation between consecutive GPS points. To reduce errors in matching, the reliability index was evaluated in real time for each match. To test the proposed map-matching method, we applied it to GPS trajectories of pedestrians and the road network data. We then assessed the performance by comparing the results with reference datasets. Our proposed method performed better with test data when compared to a conventional map-matching technique for vehicles.

  7. A dynamic system matching technique for improving the accuracy of MEMS gyroscopes

    International Nuclear Information System (INIS)

    Stubberud, Peter A.; Stubberud, Stephen C.; Stubberud, Allen R.

    2014-01-01

    A classical MEMS gyro transforms angular rates into electrical values through Euler's equations of angular rotation. Production models of a MEMS gyroscope will have manufacturing errors in the coefficients of the differential equations. The output signal of a production gyroscope will be corrupted by noise, with a major component of the noise due to the manufacturing errors. As is the case of the components in an analog electronic circuit, one way of controlling the variability of a subsystem is to impose extremely tight control on the manufacturing process so that the coefficient values are within some specified bounds. This can be expensive and may even be impossible as is the case in certain applications of micro-electromechanical (MEMS) sensors. In a recent paper [2], the authors introduced a method for combining the measurements from several nominally equal MEMS gyroscopes using a technique based on a concept from electronic circuit design called dynamic element matching [1]. Because the method in this paper deals with systems rather than elements, it is called a dynamic system matching technique (DSMT). The DSMT generates a single output by randomly switching the outputs of several, nominally identical, MEMS gyros in and out of the switch output. This has the effect of 'spreading the spectrum' of the noise caused by the coefficient errors generated in the manufacture of the individual gyros. A filter can then be used to eliminate that part of the spread spectrum that is outside the pass band of the gyro. A heuristic analysis in that paper argues that the DSMT can be used to control the effects of the random coefficient variations. In a follow-on paper [4], a simulation of a DSMT indicated that the heuristics were consistent. In this paper, analytic expressions of the DSMT noise are developed which confirm that the earlier conclusions are valid. These expressions include the various DSMT design parameters and, therefore, can be used as design

  8. A dynamic system matching technique for improving the accuracy of MEMS gyroscopes

    Science.gov (United States)

    Stubberud, Peter A.; Stubberud, Stephen C.; Stubberud, Allen R.

    2014-12-01

    A classical MEMS gyro transforms angular rates into electrical values through Euler's equations of angular rotation. Production models of a MEMS gyroscope will have manufacturing errors in the coefficients of the differential equations. The output signal of a production gyroscope will be corrupted by noise, with a major component of the noise due to the manufacturing errors. As is the case of the components in an analog electronic circuit, one way of controlling the variability of a subsystem is to impose extremely tight control on the manufacturing process so that the coefficient values are within some specified bounds. This can be expensive and may even be impossible as is the case in certain applications of micro-electromechanical (MEMS) sensors. In a recent paper [2], the authors introduced a method for combining the measurements from several nominally equal MEMS gyroscopes using a technique based on a concept from electronic circuit design called dynamic element matching [1]. Because the method in this paper deals with systems rather than elements, it is called a dynamic system matching technique (DSMT). The DSMT generates a single output by randomly switching the outputs of several, nominally identical, MEMS gyros in and out of the switch output. This has the effect of 'spreading the spectrum' of the noise caused by the coefficient errors generated in the manufacture of the individual gyros. A filter can then be used to eliminate that part of the spread spectrum that is outside the pass band of the gyro. A heuristic analysis in that paper argues that the DSMT can be used to control the effects of the random coefficient variations. In a follow-on paper [4], a simulation of a DSMT indicated that the heuristics were consistent. In this paper, analytic expressions of the DSMT noise are developed which confirm that the earlier conclusions are valid. These expressions include the various DSMT design parameters and, therefore, can be used as design tools for DSMT

  9. The application of computer color matching techniques to the matching of target colors in a food substrate: a first step in the development of foods with customized appearance.

    Science.gov (United States)

    Kim, Sandra; Golding, Matt; Archer, Richard H

    2012-06-01

    A predictive color matching model based on the colorimetric technique was developed and used to calculate the concentrations of primary food dyes needed in a model food substrate to match a set of standard tile colors. This research is the first stage in the development of novel three-dimensional (3D) foods in which color images or designs can be rapidly reproduced in 3D form. Absorption coefficients were derived for each dye, from a concentration series in the model substrate, a microwave-baked cake. When used in a linear, additive blending model these coefficients were able to predict cake color from selected dye blends to within 3 ΔE*(ab,10) color difference units, or within the limit of a visually acceptable match. Absorption coefficients were converted to pseudo X₁₀, Y₁₀, and Z₁₀ tri-stimulus values (X₁₀(P), Y₁₀(P), Z₁₀(P)) for colorimetric matching. The Allen algorithm was used to calculate dye concentrations to match the X₁₀(P), Y₁₀(P), and Z₁₀(P) values of each tile color. Several recipes for each color were computed with the tile specular component included or excluded, and tested in the cake. Some tile colors proved out-of-gamut, limited by legal dye concentrations; these were scaled to within legal range. Actual differences suggest reasonable visual matches could be achieved for within-gamut tile colors. The Allen algorithm, with appropriate adjustments of concentration outputs, could provide a sufficiently rapid and accurate calculation tool for 3D color food printing. The predictive color matching approach shows potential for use in a novel embodiment of 3D food printing in which a color image or design could be rendered within a food matrix through the selective blending of primary dyes to reproduce each color element. The on-demand nature of this food application requires rapid color outputs which could be provided by the color matching technique, currently used in nonfood industries, rather than by empirical food

  10. Development of an automated technique for failure modes and effect analysis

    DEFF Research Database (Denmark)

    Blanke, M.; Borch, Ole; Bagnoli, F.

    implementing an automated technique for Failure Modes and Effects Analysis (FMEA). This technique is based on the matrix formulation of FMEA for the investigation of failure propagation through a system. As main result, this technique will provide the design engineer with decision tables for fault handling...

  11. Development of an Automated Technique for Failure Modes and Effect Analysis

    DEFF Research Database (Denmark)

    Blanke, M.; Borch, Ole; Allasia, G.

    1999-01-01

    implementing an automated technique for Failure Modes and Effects Analysis (FMEA). This technique is based on the matrix formulation of FMEA for the investigation of failure propagation through a system. As main result, this technique will provide the design engineer with decision tables for fault handling...

  12. Data Matching Concepts and Techniques for Record Linkage, Entity Resolution, and Duplicate Detection

    CERN Document Server

    Christen, Peter

    2012-01-01

    Data matching (also known as record or data linkage, entity resolution, object identification, or field matching) is the task of identifying, matching and merging records that correspond to the same entities from several databases or even within one database. Based on research in various domains including applied statistics, health informatics, data mining, machine learning, artificial intelligence, database management, and digital libraries, significant advances have been achieved over the last decade in all aspects of the data matching process, especially on how to improve the accuracy of da

  13. Satellite cell activity is differentially affected by contraction mode in human muscle following a work-matched bout of exercise

    Directory of Open Access Journals (Sweden)

    Robert D Hyldahl

    2014-12-01

    Full Text Available Optimal repair and adaptation of skeletal muscle is facilitated by resident stem cells (satellite cells. To understand how different exercise modes influence satellite cell dynamics, we measured satellite cell activity in conjunction with markers of muscle damage and inflammation in human skeletal muscle following a single work- and intensity-matched bout of eccentric (ECC or concentric contractions (CON. Participants completed a single bout of ECC (n=7 or CON (n=7 of the knee extensors. A muscle biopsy was obtained before and 24 h after exercise. Functional measures and immunohistochemical analyses were used to determine the extent of muscle damage and indices of satellite cell activity. Cytokine concentrations were measured using a multiplexed magnetic bead assay. Isokinetic peak torque decreased following ECC (p<0.05 but not CON. Greater histological staining of the damage marker Xin was observed in muscle samples of ECC vs CON. Tenasin C immunoreactivity increased 15 fold (P<0.01 following ECC and was unchanged following CON. The inflammatory cytokines interferon gamma-induced protein 10 (IP-10 and monocyte chemotactic protein 1 (MCP-1 increased pre- to post-ECC (4.26 ± 1.4 vs. 10.49 ± 5.8 pg/ml, and 3.06 ± 0.7 vs. 6.25 ± 4.6 pg/ml, respectively; p<0.05. There was no change in any cytokine post-CON. Satellite cell content increased 27% pre- to post-ECC (0.10 ± 0.031 vs. 0.127 ± 0.041, respectively; p<0.05. There was no change in satellite cell number in CON (0.099 ± 0.027 vs. 0.102 ± 0.029, respectively. There was no fiber type-specific satellite cell response following either exercise mode. ECC but not CON resulted in an increase in MyoD positive nuclei per myofiber pre- to post-exercise (p<0.05, but there was no change in MyoD DNA binding activity in either condition. In conclusion, ECC but not CON results in functional and histological evidence of muscle damage that is accompanied by increased satellite cell activity 24 h post-exercise.

  14. Innovative operating modes and techniques for the spaceborne imaging radar-C instrument

    Science.gov (United States)

    Huneycutt, Bryan L.

    1990-01-01

    The operation of the spaceborne imaging radar-C (SIR-C) is discussed. The SIR-C instrument has been designed to obtain simultaneous multifrequency and simultaneous multipolarization radar images from a low earth orbit. It is a multiparameter imaging radar which will be flown during at least two different seasons. The instrument has been designed to operate in innovative modes such as the squint alignment mode, the extended aperture mode, the scansar mode, and the interferometry mode. The instrument has been designed to demonstrate innovative engineering techniques such as beam nulling for echo tracking, pulse-repetition frquency hopping for Doppler centroid tracking, generating the frequency step chirp for radar parameter flexibility, block floating point quantizing for data rate compression, and elevation beamwidth broadening for increasing the swath illumination.

  15. A novel sliding-mode control of induction motor using space vector modulation technique.

    Science.gov (United States)

    Fu, Tian-Jun; Xie, Wen-Fang

    2005-10-01

    This paper presents a novel sliding-mode control method for torque control of induction motors. The control principle is based on sliding-mode control combined with space vector modulation technique. The sliding-mode control contributes to the robustness of induction motor drives, and the space vector modulation improves the torque, flux, and current steady-state performance by reducing the ripple. The Lyapunov direct method is used to ensure the reaching and sustaining of sliding mode and stability of the control system. The performance of the proposed system is compared with those of conventional sliding-mode controller and classical PI controller. Finally, computer simulation results show that the proposed control scheme provides robust dynamic characteristics with low torque ripple.

  16. Risk analysis of geothermal power plants using Failure Modes and Effects Analysis (FMEA) technique

    International Nuclear Information System (INIS)

    Feili, Hamid Reza; Akar, Navid; Lotfizadeh, Hossein; Bairampour, Mohammad; Nasiri, Sina

    2013-01-01

    Highlights: • Using Failure Modes and Effects Analysis (FMEA) to find potential failures in geothermal power plants. • We considered 5 major parts of geothermal power plants for risk analysis. • Risk Priority Number (RPN) is calculated for all failure modes. • Corrective actions are recommended to eliminate or decrease the risk of failure modes. - Abstract: Renewable energy plays a key role in the transition toward a low carbon economy and the provision of a secure supply of energy. Geothermal energy is a versatile source as a form of renewable energy that meets popular demand. Since some Geothermal Power Plants (GPPs) face various failures, the requirement of a technique for team engineering to eliminate or decrease potential failures is considerable. Because no specific published record of considering an FMEA applied to GPPs with common failure modes have been found already, in this paper, the utilization of Failure Modes and Effects Analysis (FMEA) as a convenient technique for determining, classifying and analyzing common failures in typical GPPs is considered. As a result, an appropriate risk scoring of occurrence, detection and severity of failure modes and computing the Risk Priority Number (RPN) for detecting high potential failures is achieved. In order to expedite accuracy and ability to analyze the process, XFMEA software is utilized. Moreover, 5 major parts of a GPP is studied to propose a suitable approach for developing GPPs and increasing reliability by recommending corrective actions for each failure mode

  17. Mass-spring matching layers for high-frequency ultrasound transducers: a new technique using vacuum deposition.

    Science.gov (United States)

    Brown, Jeremy; Sharma, Srikanta; Leadbetter, Jeff; Cochran, Sandy; Adamson, Rob

    2014-11-01

    We have developed a technique of applying multiple matching layers to high-frequency (>30 MHz) imaging transducers, by using carefully controlled vacuum deposition alone. This technique uses a thin mass-spring matching layer approach that was previously described in a low-frequency (1 to 10 MHz) transducer design with epoxied layers. This mass- spring approach is more suitable to vacuum deposition in highfrequency transducers over the conventional quarter-wavelength resonant cavity approach, because thinner layers and more versatile material selection can be used, the difficulty in precisely lapping quarter-wavelength matching layers is avoided, the layers are less attenuating, and the layers can be applied to a curved surface. Two different 3-mm-diameter 45-MHz planar lithium niobate transducers and one geometrically curved 3-mm lithium niobate transducer were designed and fabricated using this matching layer approach with copper as the mass layer and parylene as the spring layer. The first planar lithium niobate transducer used a single mass-spring matching network, and the second planar lithium niobate transducer used a single mass-spring network to approximate the first layer in a dual quarter-wavelength matching layer system in addition to a conventional quarter-wavelength layer as the second matching layer. The curved lithium niobate transducer was press focused and used a similar mass-spring plus quarter-wavelength matching layer network. These transducers were then compared with identical transducers with no matching layers and the performance improvement was quantified. The bandwidth of the lithium niobate transducer with the single mass-spring layer was measured to be 46% and the insertion loss was measured to be -21.9 dB. The bandwidth and insertion loss of the lithium niobate transducer with the mass-spring network plus quarter-wavelength matching were measured to be 59% and -18.2 dB, respectively. These values were compared with the unmatched

  18. Minimal-Learning-Parameter Technique Based Adaptive Neural Sliding Mode Control of MEMS Gyroscope

    Directory of Open Access Journals (Sweden)

    Bin Xu

    2017-01-01

    Full Text Available This paper investigates an adaptive neural sliding mode controller for MEMS gyroscopes with minimal-learning-parameter technique. Considering the system uncertainty in dynamics, neural network is employed for approximation. Minimal-learning-parameter technique is constructed to decrease the number of update parameters, and in this way the computation burden is greatly reduced. Sliding mode control is designed to cancel the effect of time-varying disturbance. The closed-loop stability analysis is established via Lyapunov approach. Simulation results are presented to demonstrate the effectiveness of the method.

  19. Projective synchronization of uncertain scale-free network based on modified sliding mode control technique

    Science.gov (United States)

    Li, Chengren; Lü, Ling; Zhao, Guannan; Li, Gang; Tian, Jing; Gu, Jiajia; Wang, Zhouyang

    2017-05-01

    We modify sliding mode control technique from the synchronization of a single dynamic system to the synchronization of complex network. Projective synchronization of uncertain scale-free network is investigated based on modified sliding mode control technique. Further, the sliding surfaces, the identification laws of uncertain parameters and the control inputs are designed, and the condition of realizing projective synchronization of uncertain scale-free network is obtained. Finally, the Logistic systems with chaotic behavior are taken as nodes to constitute the scale-free network and the synchronization target. The simulation results show that the synchronization mechanism is effective.

  20. Three-dimensional benchmark for variable-density flow and transport simulation: matching semi-analytic stability modes for steady unstable convection in an inclined porous box

    Science.gov (United States)

    Voss, Clifford I.; Simmons, Craig T.; Robinson, Neville I.

    2010-01-01

    This benchmark for three-dimensional (3D) numerical simulators of variable-density groundwater flow and solute or energy transport consists of matching simulation results with the semi-analytical solution for the transition from one steady-state convective mode to another in a porous box. Previous experimental and analytical studies of natural convective flow in an inclined porous layer have shown that there are a variety of convective modes possible depending on system parameters, geometry and inclination. In particular, there is a well-defined transition from the helicoidal mode consisting of downslope longitudinal rolls superimposed upon an upslope unicellular roll to a mode consisting of purely an upslope unicellular roll. Three-dimensional benchmarks for variable-density simulators are currently (2009) lacking and comparison of simulation results with this transition locus provides an unambiguous means to test the ability of such simulators to represent steady-state unstable 3D variable-density physics.

  1. Evaluation of a Kalman-based block matching method to assess the bi-dimensional motion of the carotid artery wall in B-mode ultrasound sequences.

    Science.gov (United States)

    Zahnd, Guillaume; Orkisz, Maciej; Sérusclat, André; Moulin, Philippe; Vray, Didier

    2013-07-01

    We aim at investigating arterial diseases at early stage, by assessing the longitudinal (i.e. in the same direction as the blood flow) motion of the intima-media complex. This recently evidenced phenomenon has been shown to provide relevant and complementary information about vascular health. Our method assesses the longitudinal and radial motion from clinical in vivo B-mode ultrasound sequences. To estimate the trajectory of a selected point during the cardiac cycle, we introduce a block matching method that involves a temporal update of the reference block using a pixel-wise Kalman filter. The filter uses the initial gray-level of the pixel as control signal to avoid divergence due to cumulating errors. The block and search-window sizes are adapted to the tissue of interest. The method was evaluated on image sequences of the common carotid artery, acquired in 57 healthy volunteers and in 25 patients at high cardiovascular risk. Reference trajectories were generated for each sequence by averaging the tracings performed by three observers. Six different computerized techniques were also compared to our method. With a pixel size of 30 μm, the average absolute motion estimation errors were 84 ± 107 μm and 20 ± 19 μm for the longitudinal and radial directions, respectively. This accuracy was of the same order of magnitude as the inter- and intra-observers variability, and smaller than for the other methods. The estimated longitudinal motion amplitude was significantly reduced in at-risk patients compared with healthy volunteers (408 ± 281 μm vs. 643 ± 274 μm, p<0.0001). Our method can constitute a reliable and time-saving technique to investigate the arterial stiffness in clinical studies, in the objective to detect early-stage atherosclerosis. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Circuit and Measurement Technique for Radiation Induced Drift in Precision Capacitance Matching

    Science.gov (United States)

    Prasad, Sudheer; Shankar, Krishnamurthy Ganapathy

    2013-04-01

    In the design of radiation tolerant precision ADCs targeted for space market, a matched capacitor array is crucial. The drift of capacitance ratios due to radiation should be small enough not to cause linearity errors. Conventional methods for measuring capacitor matching may not achieve the desired level of accuracy due to radiation induced gain errors in the measurement circuits. In this work, we present a circuit and method for measuring capacitance ratio drift to a very high accuracy (<; 1 ppm) unaffected by radiation levels up to 150 krad.

  3. Techniques to extract physical modes in model-independent analysis of rings

    International Nuclear Information System (INIS)

    Wang, C.-X.

    2004-01-01

    A basic goal of Model-Independent Analysis is to extract the physical modes underlying the beam histories collected at a large number of beam position monitors so that beam dynamics and machine properties can be deduced independent of specific machine models. Here we discuss techniques to achieve this goal, especially the Principal Component Analysis and the Independent Component Analysis.

  4. Outcomes for Children Receiving Noninvasive Ventilation as the First-Line Mode of Mechanical Ventilation at Intensive Care Admission: A Propensity Score-Matched Cohort Study.

    OpenAIRE

    Morris, JV; Ramnarayan, P; Parslow, RC; Fleming, SJ

    2017-01-01

    Objectives: To compare outcomes of children receiving noninvasive ventilation with those receiving invasive ventilation as first-line mode of mechanical ventilation following unplanned intensive care admission. Design: Propensity score-matched cohort study analyzing data prospectively collected by the Pediatric Intensive Care Audit Network over 8 years (2007?2014). Setting: Thirty-one PICUs in the United Kingdom and Ireland; twenty-one of whom submitted Pediatric Critical Care Minimum Dataset...

  5. Practical guidance for the use of a pattern-matching technique in case-study research: a case presentation.

    Science.gov (United States)

    Almutairi, Adel F; Gardner, Glenn E; McCarthy, Alexandra

    2014-06-01

    This paper reports on a study that demonstrates how to apply pattern matching as an analytical method in case-study research. Case-study design is appropriate for the investigation of highly-contextualized phenomena that occur within the social world. Case-study design is considered a pragmatic approach that permits employment of multiple methods and data sources in order to attain a rich understanding of the phenomenon under investigation. The findings from such multiple methods can be reconciled in case-study analysis, specifically through a pattern-matching technique. Although this technique is theoretically explained in the literature, there is scant guidance on how to apply the method practically when analyzing data. This paper demonstrates the steps taken during pattern matching in a completed case-study project that investigated the influence of cultural diversity in a multicultural nursing workforce on the quality and safety of patient care. The example highlighted in this paper contributes to the practical understanding of the pattern-matching process, and can also make a substantial contribution to case-study methods. © 2013 Wiley Publishing Asia Pty Ltd.

  6. System reliability analysis using dominant failure modes identified by selective searching technique

    International Nuclear Information System (INIS)

    Kim, Dong-Seok; Ok, Seung-Yong; Song, Junho; Koh, Hyun-Moo

    2013-01-01

    The failure of a redundant structural system is often described by innumerable system failure modes such as combinations or sequences of local failures. An efficient approach is proposed to identify dominant failure modes in the space of random variables, and then perform system reliability analysis to compute the system failure probability. To identify dominant failure modes in the decreasing order of their contributions to the system failure probability, a new simulation-based selective searching technique is developed using a genetic algorithm. The system failure probability is computed by a multi-scale matrix-based system reliability (MSR) method. Lower-scale MSR analyses evaluate the probabilities of the identified failure modes and their statistical dependence. A higher-scale MSR analysis evaluates the system failure probability based on the results of the lower-scale analyses. Three illustrative examples demonstrate the efficiency and accuracy of the approach through comparison with existing methods and Monte Carlo simulations. The results show that the proposed method skillfully identifies the dominant failure modes, including those neglected by existing approaches. The multi-scale MSR method accurately evaluates the system failure probability with statistical dependence fully considered. The decoupling between the failure mode identification and the system reliability evaluation allows for effective applications to larger structural systems

  7. Carrier-Based Common Mode Voltage Control Techniques in Three-Level Diode-Clamped Inverter

    Directory of Open Access Journals (Sweden)

    Pradyumn Chaturvedi

    2012-01-01

    Full Text Available Switching converters are used in electric drive applications to produce variable voltage, variable frequency supply which generates harmful large dv/dt and high-frequency common mode voltages (CMV. Multilevel inverters generate lower CMV as compared to conventional two-level inverters. This paper presents simple carrier-based technique to control the common mode voltages in multilevel inverters using different structures of sine-triangle comparison method such as phase disposition (PD, phase opposition disposition (POD by adding common mode voltage offset signal to actual reference voltage signal. This paper also presented the method to optimize the magnitude of this offset signal to reduce CMV and total harmonic distortion in inverter output voltage. The presented techniques give comparable performance as obtained in complex space vector-based control strategy, in terms of number of commutations, magnitude, and rate of change of CMV and harmonic profile of inverter output voltage. Simulation and experimental results presented confirm the effectiveness of the proposed techniques to control the common mode voltages.

  8. Approximate Matching as a Key Technique in Organization of Natural and Artificial Intelligence

    Science.gov (United States)

    Mack, Marilyn; Lapir, Gennadi M.; Berkovich, Simon

    2000-01-01

    The basic property of an intelligent system, natural or artificial, is "understanding". We consider the following formalization of the idea of "understanding" among information systems. When system I issues a request to system 2, it expects a certain kind of desirable reaction. If such a reaction occurs, system I assumes that its request was "understood". In application to simple, "push-button" systems the situation is trivial because in a small system the required relationship between input requests and desired outputs could be specified exactly. As systems grow, the situation becomes more complex and matching between requests and actions becomes approximate.

  9. Meta-analysis on Materials and Techniques for Laparotomy Closure: The MATCH Review.

    Science.gov (United States)

    Henriksen, N A; Deerenberg, E B; Venclauskas, L; Fortelny, R H; Miserez, M; Muysoms, F E

    2018-01-10

    The aim of this systematic review and meta-analysis was to evaluate closure materials and suture techniques for emergency and elective laparotomies. The primary outcome was incisional hernia after 12 months, and the secondary outcomes were burst abdomen and surgical site infection. A systematic literature search was conducted until September 2017. The quality of the RCTs was evaluated by at least 3 assessors using critical appraisal checklists. Meta-analyses were performed. A total of 23 RCTs were included in the meta-analysis. There was no evidence from RCTs using the same suture technique in both study arms that any suture material (fast-absorbable/slowly absorbable/non-absorbable) is superior in reducing incisional hernias. There is no evidence that continuous suturing is superior in reducing incisional hernias compared to interrupted suturing. When using a slowly absorbable suture for continuous suturing in elective midline closure, the small bites technique results in significantly less incisional hernias than a large bites technique (OR 0.41; 95% CI 0.19, 0.86). There is no high-quality evidence available concerning the best suture material or technique to reduce incisional hernia rate when closing a laparotomy. When using a slowly absorbable suture and a continuous suturing technique with small tissue bites, the incisional hernia rate is significantly reduced compared with a large bites technique.

  10. Coupling single NV-centres to high-Q whispering gallery modes of a preselected frequency-matched microresonator

    International Nuclear Information System (INIS)

    Schietinger, Stefan; Benson, Oliver

    2009-01-01

    In this paper, we report the controlled coupling of fluorescence from a single NV-centre in a single nanodiamond to the high-Q modes of a preselected microsphere. Microspheres from an ensemble with a finite size distribution can be characterized precisely via white light Mie-scattering. The mode spectrum of individual spheres can be determined with high precision. A sphere with an appropriate spectrum can be selected, and a nanodiamond containing a single NV-centre can be coupled to it. The spectral position of the calculated lowest order whispering gallery modes are found to be in very good agreement with the experimentally observed resonances of the coupled fluorescence from the single NV-re.

  11. Efficient sampling techniques for uncertainty quantification in history matching using nonlinear error models and ensemble level upscaling techniques

    KAUST Repository

    Efendiev, Y.

    2009-11-01

    The Markov chain Monte Carlo (MCMC) is a rigorous sampling method to quantify uncertainty in subsurface characterization. However, the MCMC usually requires many flow and transport simulations in evaluating the posterior distribution and can be computationally expensive for fine-scale geological models. We propose a methodology that combines coarse- and fine-scale information to improve the efficiency of MCMC methods. The proposed method employs off-line computations for modeling the relation between coarse- and fine-scale error responses. This relation is modeled using nonlinear functions with prescribed error precisions which are used in efficient sampling within the MCMC framework. We propose a two-stage MCMC where inexpensive coarse-scale simulations are performed to determine whether or not to run the fine-scale (resolved) simulations. The latter is determined on the basis of a statistical model developed off line. The proposed method is an extension of the approaches considered earlier where linear relations are used for modeling the response between coarse-scale and fine-scale models. The approach considered here does not rely on the proximity of approximate and resolved models and can employ much coarser and more inexpensive models to guide the fine-scale simulations. Numerical results for three-phase flow and transport demonstrate the advantages, efficiency, and utility of the method for uncertainty assessment in the history matching. Copyright 2009 by the American Geophysical Union.

  12. Automated localization and segmentation techniques for B-mode ultrasound images: A review.

    Science.gov (United States)

    Meiburger, Kristen M; Acharya, U Rajendra; Molinari, Filippo

    2018-01-01

    B-mode ultrasound imaging is used extensively in medicine. Hence, there is a need to have efficient segmentation tools to aid in computer-aided diagnosis, image-guided interventions, and therapy. This paper presents a comprehensive review on automated localization and segmentation techniques for B-mode ultrasound images. The paper first describes the general characteristics of B-mode ultrasound images. Then insight on the localization and segmentation of tissues is provided, both in the case in which the organ/tissue localization provides the final segmentation and in the case in which a two-step segmentation process is needed, due to the desired boundaries being too fine to locate from within the entire ultrasound frame. Subsequenly, examples of some main techniques found in literature are shown, including but not limited to shape priors, superpixel and classification, local pixel statistics, active contours, edge-tracking, dynamic programming, and data mining. Ten selected applications (abdomen/kidney, breast, cardiology, thyroid, liver, vascular, musculoskeletal, obstetrics, gynecology, prostate) are then investigated in depth, and the performances of a few specific applications are compared. In conclusion, future perspectives for B-mode based segmentation, such as the integration of RF information, the employment of higher frequency probes when possible, the focus on completely automatic algorithms, and the increase in available data are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. New digital demodulator with matched filters and curve segmentation techniques for BFSK demodulation: Analytical description

    Directory of Open Access Journals (Sweden)

    Jorge Torres Gómez

    2015-09-01

    Full Text Available The present article relates in general to digital demodulation of Binary Frequency Shift Keying (BFSK. The objective of the present research is to obtain a new processing method for demodulating BFSK-signals in order to reduce hardware complexity in comparison with other methods reported. The solution proposed here makes use of the matched filter theory and curve segmentation algorithms. This paper describes the integration and configuration of a Sampler Correlator and curve segmentation blocks in order to obtain a digital receiver for a proper demodulation of the received signal. The proposed solution is shown to strongly reduce hardware complexity. In this part a presentation of the proposed solution regarding the analytical expressions is addressed. The paper covers in detail the elements needed for properly configuring the system. In a second part it is presented the implementation of the system for FPGA technology and the simulation results in order to validate the overall performance.

  14. Convolution and non convolution Perfectly Matched Layer techniques optimized at grazing incidence for high-order wave propagation modelling

    Science.gov (United States)

    Martin, Roland; Komatitsch, Dimitri; Bruthiaux, Emilien; Gedney, Stephen D.

    2010-05-01

    We present and discuss here two different unsplit formulations of the frequency shift PML based on convolution or non convolution integrations of auxiliary memory variables. Indeed, the Perfectly Matched Layer absorbing boundary condition has proven to be very efficient from a numerical point of view for the elastic wave equation to absorb both body waves with non-grazing incidence and surface waves. However, at grazing incidence the classical discrete Perfectly Matched Layer method suffers from large spurious reflections that make it less efficient for instance in the case of very thin mesh slices, in the case of sources located very close to the edge of the mesh, and/or in the case of receivers located at very large offset. In [1] we improve the Perfectly Matched Layer at grazing incidence for the seismic wave equation based on an unsplit convolution technique. This improved PML has a cost that is similar in terms of memory storage to that of the classical PML. We illustrate the efficiency of this improved Convolutional Perfectly Matched Layer based on numerical benchmarks using a staggered finite-difference method on a very thin mesh slice for an isotropic material and show that results are significantly improved compared with the classical Perfectly Matched Layer technique. We also show that, as the classical model, the technique is intrinsically unstable in the case of some anisotropic materials. In this case, retaining an idea of [2], this has been stabilized by adding correction terms adequately along any coordinate axis [3]. More specifically this has been applied to the spectral-element method based on a hybrid first/second order time integration scheme in which the Newmark time marching scheme allows us to match perfectly at the base of the absorbing layer a velocity-stress formulation in the PML and a second order displacement formulation in the inner computational domain.Our CPML unsplit formulation has the advantage to reduce the memory storage of CPML

  15. Conventional QT Variability Measurement vs. Template Matching Techniques: Comparison of Performance Using Simulated and Real ECG

    Science.gov (United States)

    Baumert, Mathias; Starc, Vito; Porta, Alberto

    2012-01-01

    Increased beat-to-beat variability in the QT interval (QTV) of ECG has been associated with increased risk for sudden cardiac death, but its measurement is technically challenging and currently not standardized. The aim of this study was to investigate the performance of commonly used beat-to-beat QT interval measurement algorithms. Three different methods (conventional, template stretching and template time shifting) were subjected to simulated data featuring typical ECG recording issues (broadband noise, baseline wander, amplitude modulation) and real short-term ECG of patients before and after infusion of sotalol, a QT interval prolonging drug. Among the three algorithms, the conventional algorithm was most susceptible to noise whereas the template time shifting algorithm showed superior overall performance on simulated and real ECG. None of the algorithms was able to detect increased beat-to-beat QT interval variability after sotalol infusion despite marked prolongation of the average QT interval. The QTV estimates of all three algorithms were inversely correlated with the amplitude of the T wave. In conclusion, template matching algorithms, in particular the time shifting algorithm, are recommended for beat-to-beat variability measurement of QT interval in body surface ECG. Recording noise, T wave amplitude and the beat-rejection strategy are important factors of QTV measurement and require further investigation. PMID:22860030

  16. Conventional QT variability measurement vs. template matching techniques: comparison of performance using simulated and real ECG.

    Directory of Open Access Journals (Sweden)

    Mathias Baumert

    Full Text Available Increased beat-to-beat variability in the QT interval (QTV of ECG has been associated with increased risk for sudden cardiac death, but its measurement is technically challenging and currently not standardized. The aim of this study was to investigate the performance of commonly used beat-to-beat QT interval measurement algorithms. Three different methods (conventional, template stretching and template time shifting were subjected to simulated data featuring typical ECG recording issues (broadband noise, baseline wander, amplitude modulation and real short-term ECG of patients before and after infusion of sotalol, a QT interval prolonging drug. Among the three algorithms, the conventional algorithm was most susceptible to noise whereas the template time shifting algorithm showed superior overall performance on simulated and real ECG. None of the algorithms was able to detect increased beat-to-beat QT interval variability after sotalol infusion despite marked prolongation of the average QT interval. The QTV estimates of all three algorithms were inversely correlated with the amplitude of the T wave. In conclusion, template matching algorithms, in particular the time shifting algorithm, are recommended for beat-to-beat variability measurement of QT interval in body surface ECG. Recording noise, T wave amplitude and the beat-rejection strategy are important factors of QTV measurement and require further investigation.

  17. TECHNIQUES AND TACTICS IN BASKETBALL ACCORDING TO THE INTENSITY IN OFFICIAL MATCHES

    Directory of Open Access Journals (Sweden)

    José Francisco Daniel

    Full Text Available ABSTRACT Introduction: Basketball is characterized as an intermittent sport in which currently stand out the highest intensity in which the actions occur, demanding for sport performance the optimum and homogeneous development of physical, technical, tactical, psychological and intellectual components. In this sense, the understanding of the game according to the technical and tactical actions performed and the knowledge of body’s responses are important for planning, monitoring and control of the training. Objective: The aim of this study was to describe the intensity of basketball tactical actions and the relationships between technical actions and intensity during the different game periods (GP. Methods: Ten athletes of the Brazilian male basketball elite participated in this study (27.60±5.54 years, 192.62±7.63 cm, 91.60±11.51 kg, 10.66±4.11% of body fat in six official matches of the National Basketball League (LNB, Brazil. Anthropometric measures and motor tests were performed and tactical (defensive, offensive and transition, technical [shares number (SN and efficiency ratio (ER] and physical actions [percentage of lactate threshold heart rate (%HRthr] were correlated. Spearman’s correlation coefficient was used between SN, ER and %HRthr. Results: The main results point to: (1 positive and significant relationship (except the 4th GP between SN, ER and %HRthr; (2 tactical actions presented HR near the lactate threshold, being apparently the highest median for the transitions (107.4%HRthr. Conclusion: The game is intense, with moments of HRpeak, but the median is slightly above of HRthr, that it is where the best relationship between SN and ER occurs.

  18. Speckle noise reduction technique for Lidar echo signal based on self-adaptive pulse-matching independent component analysis

    Science.gov (United States)

    Xu, Fan; Wang, Jiaxing; Zhu, Daiyin; Tu, Qi

    2018-04-01

    Speckle noise has always been a particularly tricky problem in improving the ranging capability and accuracy of Lidar system especially in harsh environment. Currently, effective speckle de-noising techniques are extremely scarce and should be further developed. In this study, a speckle noise reduction technique has been proposed based on independent component analysis (ICA). Since normally few changes happen in the shape of laser pulse itself, the authors employed the laser source as a reference pulse and executed the ICA decomposition to find the optimal matching position. In order to achieve the self-adaptability of algorithm, local Mean Square Error (MSE) has been defined as an appropriate criterion for investigating the iteration results. The obtained experimental results demonstrated that the self-adaptive pulse-matching ICA (PM-ICA) method could effectively decrease the speckle noise and recover the useful Lidar echo signal component with high quality. Especially, the proposed method achieves 4 dB more improvement of signal-to-noise ratio (SNR) than a traditional homomorphic wavelet method.

  19. \\mathscr{H}_2 optimal control techniques for resistive wall mode feedback in tokamaks

    Science.gov (United States)

    Clement, Mitchell; Hanson, Jeremy; Bialek, Jim; Navratil, Gerald

    2018-04-01

    DIII-D experiments show that a new, advanced algorithm enables resistive wall mode (RWM) stability control in high performance discharges using external coils. DIII-D can excite strong, locked or nearly locked external kink modes whose rotation frequencies and growth rates are on the order of the magnetic flux diffusion time of the vacuum vessel wall. Experiments have shown that modern control techniques like linear quadratic Gaussian (LQG) control require less current than the proportional controller in use at DIII-D when using control coils external to DIII-D’s vacuum vessel. Experiments were conducted to develop control of a rotating n  =  1 perturbation using an LQG controller derived from VALEN and external coils. Feedback using this LQG algorithm outperformed a proportional gain only controller in these perturbation experiments over a range of frequencies. Results from high βN experiments also show that advanced feedback techniques using external control coils may be as effective as internal control coil feedback using classical control techniques.

  20. Modeling of PV Systems Based on Inflection Points Technique Considering Reverse Mode

    Directory of Open Access Journals (Sweden)

    Bonie J. Restrepo-Cuestas

    2013-11-01

    Full Text Available This paper proposes a methodology for photovoltaic (PV systems modeling, considering their behavior in both direct and reverse operating mode and considering mismatching conditions. The proposed methodology is based on the inflection points technique with a linear approximation to model the bypass diode and a simplified PV model. The proposed mathematical model allows to evaluate the energetic performance of a PV system, exhibiting short simulation times in large PV systems. In addition, this methodology allows to estimate the condition of the modules affected by the partial shading since it is possible to know the power dissipated due to its operation at the second quadrant.

  1. Electrocardiogram signal denoising based on empirical mode decomposition technique: an overview

    Science.gov (United States)

    Han, G.; Lin, B.; Xu, Z.

    2017-03-01

    Electrocardiogram (ECG) signal is nonlinear and non-stationary weak signal which reflects whether the heart is functioning normally or abnormally. ECG signal is susceptible to various kinds of noises such as high/low frequency noises, powerline interference and baseline wander. Hence, the removal of noises from ECG signal becomes a vital link in the ECG signal processing and plays a significant role in the detection and diagnosis of heart diseases. The review will describe the recent developments of ECG signal denoising based on Empirical Mode Decomposition (EMD) technique including high frequency noise removal, powerline interference separation, baseline wander correction, the combining of EMD and Other Methods, EEMD technique. EMD technique is a quite potential and prospective but not perfect method in the application of processing nonlinear and non-stationary signal like ECG signal. The EMD combined with other algorithms is a good solution to improve the performance of noise cancellation. The pros and cons of EMD technique in ECG signal denoising are discussed in detail. Finally, the future work and challenges in ECG signal denoising based on EMD technique are clarified.

  2. Nonlinear adaptive control based on fuzzy sliding mode technique and fuzzy-based compensator.

    Science.gov (United States)

    Nguyen, Sy Dzung; Vo, Hoang Duy; Seo, Tae-Il

    2017-09-01

    It is difficult to efficiently control nonlinear systems in the presence of uncertainty and disturbance (UAD). One of the main reasons derives from the negative impact of the unknown features of UAD as well as the response delay of the control system on the accuracy rate in the real time of the control signal. In order to deal with this, we propose a new controller named CO-FSMC for a class of nonlinear control systems subjected to UAD, which is constituted of a fuzzy sliding mode controller (FSMC) and a fuzzy-based compensator (CO). Firstly, the FSMC and CO are designed independently, and then an adaptive fuzzy structure is discovered to combine them. Solutions for avoiding the singular cases of the fuzzy-based function approximation and reducing the calculating cost are proposed. Based on the solutions, fuzzy sliding mode technique, lumped disturbance observer and Lyapunov stability analysis, a closed-loop adaptive control law is formulated. Simulations along with a real application based on a semi-active train-car suspension are performed to fully evaluate the method. The obtained results reflected that vibration of the chassis mass is insensitive to UAD. Compared with the other fuzzy sliding mode control strategies, the CO-FSMC can provide the best control ability to reduce unwanted vibrations. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  3. A high-resolution processing technique for improving the energy of weak signal based on matching pursuit

    Directory of Open Access Journals (Sweden)

    Shuyan Wang

    2016-05-01

    Full Text Available This paper proposes a new method to improve the resolution of the seismic signal and to compensate the energy of weak seismic signal based on matching pursuit. With a dictionary of Morlet wavelets, matching pursuit algorithm can decompose a seismic trace into a series of wavelets. We abstract complex-trace attributes from analytical expressions to shrink the search range of amplitude, frequency and phase. In addition, considering the level of correlation between constituent wavelets and average wavelet abstracted from well-seismic calibration, we can obtain the search range of scale which is an important adaptive parameter to control the width of wavelet in time and the bandwidth of frequency. Hence, the efficiency of selection of proper wavelets is improved by making first a preliminary estimate and refining a local selecting range. After removal of noise wavelets, we integrate useful wavelets which should be firstly executed by adaptive spectral whitening technique. This approach can improve the resolutions of seismic signal and enhance the energy of weak wavelets simultaneously. The application results of real seismic data show this method has a good perspective of application.

  4. A numerical/empirical technique for history matching and predicting cyclic steam performance in Canadian oil sands reservoirs

    Science.gov (United States)

    Leshchyshyn, Theodore Henry

    The oil sands of Alberta contain some one trillion barrels of bitumen-in-place, most contained in the McMurray, Wabiskaw, Clearwater, and Grand Rapids formations. Depth of burial is 0--550 m, 10% of which is surface mineable, the rest recoverable by in-situ technology-driven enhanced oil recovery schemes. To date, significant commercial recovery has been attributed to Cyclic Steam Stimulation (CSS) using vertical wellbores. Other techniques, such as Steam Assisted Gravity Drainage (SAGD) are proving superior to other recovery methods for increasing early oil production but at initial higher development and/or operating costs. Successful optimization of bitumen production rates from the entire reservoir is ultimately decided by the operator's understanding of the reservoir in its original state and/or the positive and negative changes which occur in oil sands and heavy oil deposits upon heat stimulation. Reservoir description is the single most important factor in attaining satisfactory history matches and forecasts for optimized production of the commercially-operated processes. Reservoir characterization which lacks understanding can destroy a project. For example, incorrect assumptions in the geological model for the Wolf Lake Project in northeast Alberta resulted in only about one-half of the predicted recovery by the original field process. It will be shown here why the presence of thin calcite streaks within oil sands can determine the success or failure of a commercial cyclic steam project. A vast amount of field data, mostly from the Primrose Heavy Oil Project (PHOP) near Cold Lake, Alberta, enabled the development a simple set of correlation curves for predicting bitumen production using CSS. A previously calibtrated thermal numerical simulation model was used in its simplist form, that is, a single layer, radial grid blocks, "fingering" or " dilation" adjusted permeability curves, and no simulated fracture, to generate the first cycle production

  5. Predicting core losses and efficiency of SRM in continuous current mode of operation using improved analytical technique

    Science.gov (United States)

    Parsapour, Amir; Dehkordi, Behzad Mirzaeian; Moallem, Mehdi

    2015-03-01

    In applications in which the high torque per ampere at low speed and rated power at high speed are required, the continuous current method is the best solution. However, there is no report on calculating the core loss of SRM in continuous current mode of operation. Efficiency and iron loss calculation which are complex tasks in case of conventional mode of operation is even more involved in continuous current mode of operation. In this paper, the Switched Reluctance Motor (SRM) is modeled using finite element method and core loss and copper loss of SRM in discontinuous and continuous current modes of operation are calculated using improved analytical techniques to include the minor loop losses in continuous current mode of operation. Motor efficiency versus speed in both operation modes is obtained and compared.

  6. Failure modes induced by natural radiation environments on DRAM memories: study, test methodology and mitigation technique

    International Nuclear Information System (INIS)

    Bougerol, A.

    2011-05-01

    DRAMs are frequently used in space and aeronautic systems. Their sensitivity to cosmic radiations have to be known in order to satisfy reliability requirements for critical applications. These evaluations are traditionally done with particle accelerators. However, devices become more complex with technology integration. Therefore new effects appear, inducing longer and more expensive tests. There is a complementary solution: the pulsed laser, which triggers similar effects as particles. Thanks to these two test tools, main DRAM radiation failure modes were studied: SEUs (Single Event Upset) in memory blocks, and SEFIs (Single Event Functional Interrupt) in peripheral circuits. This work demonstrates the influence of test patterns on SEU and SEFI sensitivities depending on technology used. In addition, this study identifies the origin of the most frequent type of SEFIs. Moreover, laser techniques were developed to quantify sensitive surfaces of the different effects. This work led to a new test methodology for industry, in order to optimize test cost and efficiency using both pulsed laser beams and particle accelerators. Finally, a new fault tolerant technique is proposed: based on DRAM cell radiation immunity when discharged, this technique allows to correct all bits of a logic word. (author)

  7. A Robust Automatic Ionospheric O/X Mode Separation Technique for Vertical Incidence Sounders

    Science.gov (United States)

    Harris, T. J.; Pederick, L. H.

    2017-12-01

    The sounding of the ionosphere by a vertical incidence sounder (VIS) is the oldest and most common technique for determining the state of the ionosphere. The automatic extraction of relevant ionospheric parameters from the ionogram image, referred to as scaling, is important for the effective utilization of data from large ionospheric sounder networks. Due to the Earth's magnetic field, the ionosphere is birefringent at radio frequencies, so a VIS will typically see two distinct returns for each frequency. For the automatic scaling of ionograms, it is highly desirable to be able to separate the two modes. Defence Science and Technology Group has developed a new VIS solution which is based on direct digital receiver technology and includes an algorithm to separate the O and X modes. This algorithm can provide high-quality separation even in difficult ionospheric conditions. In this paper we describe the algorithm and demonstrate its consistency and reliability in successfully separating 99.4% of the ionograms during a 27 day experimental campaign under sometimes demanding ionospheric conditions.

  8. Reduction of heart sound interference from lung sound signals using empirical mode decomposition technique.

    Science.gov (United States)

    Mondal, Ashok; Bhattacharya, P S; Saha, Goutam

    2011-01-01

    During the recording time of lung sound (LS) signals from the chest wall of a subject, there is always heart sound (HS) signal interfering with it. This obscures the features of lung sound signals and creates confusion on pathological states, if any, of the lungs. A novel method based on empirical mode decomposition (EMD) technique is proposed in this paper for reducing the undesired heart sound interference from the desired lung sound signals. In this, the mixed signal is split into several components. Some of these components contain larger proportions of interfering signals like heart sound, environmental noise etc. and are filtered out. Experiments have been conducted on simulated and real-time recorded mixed signals of heart sound and lung sound. The proposed method is found to be superior in terms of time domain, frequency domain, and time-frequency domain representations and also in listening test performed by pulmonologist.

  9. Spatial mode discrimination using second harmonic generation

    DEFF Research Database (Denmark)

    Delaubert, Vincent; Lassen, Mikael Østergaard; Pulford, David

    2007-01-01

    Second harmonic generation can be used as a technique for controlling the spatial mode structure of optical beams. We demonstrate experimentally the generation of higher order spatial modes, and that it is possible to use nonlinear phase matching as a predictable and robust technique for the conv...

  10. Outcomes for Children Receiving Noninvasive Ventilation as the First-Line Mode of Mechanical Ventilation at Intensive Care Admission: A Propensity Score-Matched Cohort Study.

    Science.gov (United States)

    Morris, Jenny V; Ramnarayan, Padmanabhan; Parslow, Roger C; Fleming, Sarah J

    2017-06-01

    To compare outcomes of children receiving noninvasive ventilation with those receiving invasive ventilation as first-line mode of mechanical ventilation following unplanned intensive care admission. Propensity score-matched cohort study analyzing data prospectively collected by the Pediatric Intensive Care Audit Network over 8 years (2007-2014). Thirty-one PICUs in the United Kingdom and Ireland; twenty-one of whom submitted Pediatric Critical Care Minimum Dataset data for the entire study period. Children consecutively admitted to study PICUs. Planned admissions following surgery, unplanned admissions from other hospitals, those on chronic ventilation, and those who did not receive mechanical ventilation on the day of PICU admission were excluded. Use of noninvasive ventilation, rather than invasive ventilation, as the first-line mode of mechanical ventilation. PICU mortality, length of ventilation, length of PICU stay, and ventilator-free days at day 28. During the study period, there were 151,128 PICU admissions. A total of 15,144 admissions (10%) were eligible for analysis once predefined exclusion criteria were applied: 4,804 (31.7%) received "noninvasive ventilation first," whereas 10,221 (67.5%) received "invasive ventilation first"; 119 (0.8%) admissions could not be classified. Admitting PICU site explained 6.5% of the variation in first-line mechanical ventilation group (95% CI, 2.0-19.0%). In propensity score-matched analyses, receiving noninvasive ventilation first was associated with a significant reduction in mortality by 3.1% (95% CI, 1.7-4.6%), length of ventilation by 1.6 days (95% CI, 1.0-2.3), and length of PICU stay by 2.1 days (95% CI, 1.3-3.0), as well as an increase in ventilator-free days at day 28 by 3.7 days (95% CI, 3.1-4.3). Use of noninvasive ventilation as first-line mode of mechanical ventilation in critically ill children admitted to PICU in an unplanned fashion may be associated with significant clinical benefits. Further high

  11. An Analysis Technique/Automated Tool for Comparing and Tracking Analysis Modes of Different Finite Element Models

    Science.gov (United States)

    Towner, Robert L.; Band, Jonathan L.

    2012-01-01

    An analysis technique was developed to compare and track mode shapes for different Finite Element Models. The technique may be applied to a variety of structural dynamics analyses, including model reduction validation (comparing unreduced and reduced models), mode tracking for various parametric analyses (e.g., launch vehicle model dispersion analysis to identify sensitivities to modal gain for Guidance, Navigation, and Control), comparing models of different mesh fidelity (e.g., a coarse model for a preliminary analysis compared to a higher-fidelity model for a detailed analysis) and mode tracking for a structure with properties that change over time (e.g., a launch vehicle from liftoff through end-of-burn, with propellant being expended during the flight). Mode shapes for different models are compared and tracked using several numerical indicators, including traditional Cross-Orthogonality and Modal Assurance Criteria approaches, as well as numerical indicators obtained by comparing modal strain energy and kinetic energy distributions. This analysis technique has been used to reliably identify correlated mode shapes for complex Finite Element Models that would otherwise be difficult to compare using traditional techniques. This improved approach also utilizes an adaptive mode tracking algorithm that allows for automated tracking when working with complex models and/or comparing a large group of models.

  12. "Trying, But Failing" - The Role of Inhaler Technique and Mode of Delivery in Respiratory Medication Adherence.

    Science.gov (United States)

    Braido, Fulvio; Chrystyn, Henry; Baiardini, Ilaria; Bosnic-Anticevich, Sinthia; van der Molen, Thys; Dandurand, Ronald J; Chisholm, Alison; Carter, Victoria; Price, David

    2016-01-01

    Inhaled therapies are the backbone of asthma and chronic obstructive pulmonary disease management, helping to target therapy at the airways. Adherence to prescribed treatment is necessary to ensure achievement of the clinician's desired therapeutic effect. In the case of inhaled therapies, this requires patients' acceptance of their need for inhaled therapy together with successful mastery of the inhaler technique specific to their device(s). This article reviews a number of challenges and barriers that inhaled mode of delivery can pose to optimum adherence-to therapy initiation and, thereafter, to successful implementation and persistence. The potential effects on adherence of different categories of devices, their use in multiplicity, and the mixing of device categories are discussed. Common inhaler errors identified by the international Implementing Helping Asthma in Real People (iHARP) study are summarized, and adherence intervention opportunities for health care professionals are offered. Better knowledge of common errors can help practicing clinicians identify their occurrence among patients and prompt remedial actions, such as tailored education, inhaler technique retraining, and/or shared decision making with patients regarding suitable alternatives. Optimizing existing therapy delivery, or switching to a suitable alternative, can help avoid unnecessary escalation of treatment and health care resources. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Reusable Launch Vehicle Attitude Control Using a Time-Varying Sliding Mode Control Technique

    Science.gov (United States)

    Shtessel, Yuri B.; Zhu, J. Jim; Daniels, Dan; Jackson, Scott (Technical Monitor)

    2002-01-01

    In this paper we present a time-varying sliding mode control (TVSMC) technique for reusable launch vehicle (RLV) attitude control in ascent and entry flight phases. In ascent flight the guidance commands Euler roll, pitch and yaw angles, and in entry flight it commands the aerodynamic angles of bank, attack and sideslip. The controller employs a body rate inner loop and the attitude outer loop, which are separated in time-scale by the singular perturbation principle. The novelty of the TVSMC is that both the sliding surface and the boundary layer dynamics can be varied in real time using the PD-eigenvalue assignment technique. This salient feature is used to cope with control command saturation and integrator windup in the presence of severe disturbance or control effector failure, which enhances the robustness and fault tolerance of the controller. The TV-SMC ascent and descent designs are currently being tested with high fidelity, 6-DOF dispersion simulations. The test results will be presented in the final version of this paper.

  14. Assisted reproduction technique outcomes for fresh versus deferred cryopreserved day-2 embryo transfer: a retrospective matched cohort study.

    Science.gov (United States)

    Bourdon, Mathilde; Santulli, Pietro; Gayet, Vanessa; Maignien, Chloé; Marcellin, Louis; Pocate-Cheriet, Khaled; Chapron, Charles

    2017-03-01

    Ovarian stimulation could adversely affect endometrial receptivity and consequently embryo implantation. One emerging strategy is the 'freeze-all' approach. Most studies have focused on blastocyst transfers, with limited research on day-2 deferred cryopreserved embryo transfers. In this large retrospective cohort study, outcomes were compared between day-2 fresh versus deferred cryopreserved embryo transfers. After matching by age and number of previous cycles, 325 cycles were included in the fresh group and 325 in the deferred cryopreserved embryo transfers group: no significant differences were found between groups in implantation (0.20 ± 0.33 versus 0.17 ± 0.31, respectively) and ongoing pregnancy rates (21.85% versus 18.46%). Independent predictors for ongoing pregnancy after a multiple logistic regression analysis were the women's age (OR = 0.92; 95% CI 0.88 to 0.97), body mass index (OR = 0.94; 95% CI 0.89 to 0.99), the number of two pronuclei embryos (OR = 1.19; 95% CI 1.04 to 1.40) and at least one grade 1 embryo transferred (OR = 1.97; 95% CI 1.26 to 3.05). In the case of a day-2 embryo transfer, outcomes after treatment with assisted reproduction techniques are similar for fresh versus deferred cryopreserved embryo transfers when pre-transfer progesterone exposures are similar in the two groups. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  15. Predicting core losses and efficiency of SRM in continuous current mode of operation using improved analytical technique

    Energy Technology Data Exchange (ETDEWEB)

    Parsapour, Amir, E-mail: amirparsapour@gmail.com [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Dehkordi, Behzad Mirzaeian, E-mail: mirzaeian@eng.ui.ac.ir [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Moallem, Mehdi, E-mail: moallem@cc.iut.ac.ir [Department of Electrical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2015-03-15

    In applications in which the high torque per ampere at low speed and rated power at high speed are required, the continuous current method is the best solution. However, there is no report on calculating the core loss of SRM in continuous current mode of operation. Efficiency and iron loss calculation which are complex tasks in case of conventional mode of operation is even more involved in continuous current mode of operation. In this paper, the Switched Reluctance Motor (SRM) is modeled using finite element method and core loss and copper loss of SRM in discontinuous and continuous current modes of operation are calculated using improved analytical techniques to include the minor loop losses in continuous current mode of operation. Motor efficiency versus speed in both operation modes is obtained and compared. - Highlights: • Continuous current method for Switched Reluctance Motor (SRM) is explained. • An improved analytical technique is presented for SRM core loss calculation. • SRM losses in discontinuous and continuous current operation modes are presented. • Effect of mutual inductances on SRM performance is investigated.

  16. New modes of particle acceleration, techniques ampersand sources symposium. Summary report

    International Nuclear Information System (INIS)

    Parsa, Z.

    1996-01-01

    A Symposium on open-quotes New Modes of Particle Acceleration Technique and Sourcesclose quotes was held August 19-23, 1996 at the Institute for Theoretical Physics (ITP) in Santa Barbara. This was the first of the 3 symposia hosted by the ITP and supported by its sponsor the National Science Foundation, as part of our open-quotes New Ideas for Particle Acceleratorsclose quotes program. The symposia was organized and chaired by Dr. Zohreh Parsa of ITP/Brookhaven National Laboratory. This Symposium provided a perspective on the future direction of the Advanced Accelerator Research. The experimental study of elementary particles has become concentrated at a few large laboratories throughout the world because of the size and cost of the accelerator facilities needed for this work. For example, the Large Hadron Collider (LHC) at CERN, currently under construction, is 27 km in circumference and is being financed by the European membership of CERN plus contributions from non-member nations. An evolutionary approach to construction of ever higher energy colliders will only continue this trend towards high cost and large size

  17. Dynamic arrythmia filtration for gated blood pool imaging: Validation against list - Mode technique

    International Nuclear Information System (INIS)

    Juni, J.E.; Wallis, J.; Rocchini, A.; Wu-Connolly, L.

    1985-01-01

    Normal resting heart rate variation distort the diastolic portions of time-activity curves (TACs) generated from gated blood pool (GBP) images. This alters calculated measures of diastolic function e.g. peak filling rate (PFR). The authors compared diastolic filling parameters obtained by two methods of arrythmia removal, list-mode (LM) acquisition and a new approach, dynamic arrythima filtration (DAF). LM acquisition techniques reject beats of unusual cycle length, thus reducing the TAC distortions caused by heart rate variation but is time consuming and requires large amounts of disk storage. In DAF systems data is evaluated for cycle length in real-time and accepted or rejected immediately according to preset, operator determined cycle-length criteria, thus eliminating the need for post-processing of data and for large mass data storage. The authors prospectively determined EF, time to end-systole (TES), PFR, ad TPFR on 25 GBP patients. Camera and ECG data were sent simultaneously to 2 computers. One acquired data via LM and the other by DAF. Fluctuations in heart rate during GBP acquisition may cause errors in calculation of filling parameters. Both LM and DAF remove cycles of unusual length. DAF is less time consuming and technically demanding than LM and provides results which correlate closely with those obtained by LM

  18. A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity

    Directory of Open Access Journals (Sweden)

    Juan D. Reverte-Ors

    2017-06-01

    Full Text Available In this paper, a novel technique to achieve precise temperatures in food sterilization has been proposed. An accurate temperature profile is needed in order to reach a commitment between the total removal of pathogens inside the product and the preservation of nutritional and organoleptic characteristics. The minimal variation of the target temperature in the sample by means of a monitoring and control software platform, allowing temperature stabilization over 100 °C, is the main goal of this work. A cylindrical microwave oven, under pressure conditions and continuous control of the microwave supply power as function of the final temperature inside the sample, has been designed and developed with conditions of single-mode resonance. The uniform heating in the product is achieved by means of sample movement and the self-regulated power control using the measured temperature. Finally, for testing the sterilization of food with this technology, specific biological validation based on Bacillus cereus as a biosensor of heat inactivation has been incorporated as a distribution along the sample in the experimental process to measure the colony-forming units (CFUs for different food samples (laboratory medium, soup, or fish-based animal by-products. The obtained results allow the validation of this new technology for food sterilization with precise control of the microwave system to ensure the uniform elimination of pathogens using high temperatures.

  19. Contribution of acoustic modes to the density of vibrational states measured by inelastic scattering techniques

    International Nuclear Information System (INIS)

    Chumakov, A. I.; Bosak, A.; Rueffer, R.

    2009-01-01

    We consider the contribution of acoustic modes to the density of vibrational states measured by nuclear inelastic, inelastic x-ray, and inelastic neutron scattering. In nuclear and x-ray scattering, the low-energy part of the density of states (DOS) is compared with the contribution of acoustic modes to the generalized density of states. Different to that, in neutron scattering the DOS is compared with the contribution of acoustic modes to the true density of states. We argue that in general this is not correct and that similar to nuclear and x-ray scattering, the neutron data in most cases must also be compared with the contribution of acoustic modes to the generalized DOS. For neutron scattering, this contribution usually is smaller than the contribution to the true DOS. Thus, the comparison of the neutron data with the contribution of acoustic modes to the true DOS systematically overestimates the level of acoustic modes. However, an extrapolation of the neutron DOS to zero energy often exceeds even this overestimated level. In our eyes, even for glasses the manifold excess of the extrapolation of the neutron DOS to zero energy over the expected level of acoustic modes seems to be unreasonable even though in this case one can still argue on existing of additional soft modes. However, a similar excess observed also for crystalline samples clearly indicates an uncertainty of the absolute scale of the DOS measured by neutron scattering.

  20. Production Efficiency and Market Orientation in Food Crops in North West Ethiopia: Application of Matching Technique for Impact Assessment.

    Directory of Open Access Journals (Sweden)

    Habtamu Yesigat Ayenew

    Full Text Available Agricultural technologies developed by national and international research institutions were not benefiting the rural population of Ethiopia to the extent desired. As a response, integrated agricultural extension approaches are proposed as a key strategy to transform the smallholder farming sector. Improving Productivity and Market Success (IPMS of Ethiopian Farmers project is one of the development projects initiated by integrating productivity enhancement technological schemes with market development model. This paper explores the impact of the project intervention in the smallholder farmers' wellbeing.To test the research hypothesis of whether the project brought a significant change in the input use, marketed surplus, efficiency and income of farm households, we use a cross-section data from 200 smallholder farmers in Northwest Ethiopia, collected through multi-stage sampling procedure. To control for self-selection from observable characteristics of the farm households, we employ Propensity Score Matching (PSM. We finally use Data Envelopment Analysis (DEA techniques to estimate technical efficiency of farm households.The outcome of the research is in line with the premises that the participation of the household in the IPMS project improves purchased input use, marketed surplus, efficiency of farms and the overall gain from farming. The participant households on average employ more purchased agricultural inputs and gain higher gross margin from the production activities as compared to the non-participant households. The non-participant households on average supply less output (measured both in monetary terms and proportion of total produce to the market as compared to their participant counterparts. Except for the technical efficiency of production in potato, project participant households are better-off in production efficiency compared with the non-participant counterparts.We verified the idea that Improving Productivity and Market

  1. Damage Modes Recognition and Hilbert-Huang Transform Analyses of CFRP Laminates Utilizing Acoustic Emission Technique

    Science.gov (United States)

    WenQin, Han; Ying, Luo; AiJun, Gu; Yuan, Fuh-Gwo

    2016-04-01

    Discrimination of acoustic emission (AE) signals related to different damage modes is of great importance in carbon fiber-reinforced plastic (CFRP) composite materials. To gain a deeper understanding of the initiation, growth and evolution of the different types of damage, four types of specimens for different lay-ups and orientations and three types of specimens for interlaminar toughness tests are subjected to tensile test along with acoustic emission monitoring. AE signals have been collected and post-processed, the statistical results show that the peak frequency of AE signal can distinguish various damage modes effectively. After a AE signal were decomposed by Empirical Mode Decomposition (EMD) method, it may separate and extract all damage modes included in this AE signal apart from damage mode corresponding to the peak frequency. Hilbert-Huang Transform (HHT) of AE signals can clearly illustrate the frequency distribution of Intrinsic Mode Functions (IMF) components in time-scale in different damage stages, and can calculate accurate instantaneous frequency for damage modes recognition to help understanding the damage process.

  2. Efficiency of Switch-Mode Power Audio Amplifiers - Test Signals and Measurement Techniques

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Knott, Arnold; Andersen, Michael A. E.

    2016-01-01

    Switch-mode technology is greatly used for audio amplification. This is mainly due to the great efficiency this technology offers. Normally the efficiency of a switch-mode audio amplifier is measured using a sine wave input. However this paper shows that sine waves represent real audio very poorly....... An alternative signal is proposed for test purposes. The efficiency of a switch-mode power audio amplifier is modelled and measured with both sine wave and the proposed test signal as inputs. The results show that the choice of switching devices with low on resistances are unfairly favored when measuring...

  3. Is There a Purchase Limit on Regional Growth? A Quasi-experimental Evaluation of Investment Grants Using Matching Techniques

    DEFF Research Database (Denmark)

    Mitze, Timo Friedel; Paloyo, Alfredo R.; Alecke, Björn

    2015-01-01

    growth associated with a maximum subsidy level beyond which financial support does not generate further labor-productivity growth. In other words, there is a “purchase limit” on regional growth. Although the matching approach is very appealing due to its methodological rigor and didactical clarity...

  4. Estimating the Counterfactual Impact of Conservation Programs on Land Cover Outcomes: The Role of Matching and Panel Regression Techniques.

    Science.gov (United States)

    Jones, Kelly W; Lewis, David J

    2015-01-01

    Deforestation and conversion of native habitats continues to be the leading driver of biodiversity and ecosystem service loss. A number of conservation policies and programs are implemented--from protected areas to payments for ecosystem services (PES)--to deter these losses. Currently, empirical evidence on whether these approaches stop or slow land cover change is lacking, but there is increasing interest in conducting rigorous, counterfactual impact evaluations, especially for many new conservation approaches, such as PES and REDD, which emphasize additionality. In addition, several new, globally available and free high-resolution remote sensing datasets have increased the ease of carrying out an impact evaluation on land cover change outcomes. While the number of conservation evaluations utilizing 'matching' to construct a valid control group is increasing, the majority of these studies use simple differences in means or linear cross-sectional regression to estimate the impact of the conservation program using this matched sample, with relatively few utilizing fixed effects panel methods--an alternative estimation method that relies on temporal variation in the data. In this paper we compare the advantages and limitations of (1) matching to construct the control group combined with differences in means and cross-sectional regression, which control for observable forms of bias in program evaluation, to (2) fixed effects panel methods, which control for observable and time-invariant unobservable forms of bias, with and without matching to create the control group. We then use these four approaches to estimate forest cover outcomes for two conservation programs: a PES program in Northeastern Ecuador and strict protected areas in European Russia. In the Russia case we find statistically significant differences across estimators--due to the presence of unobservable bias--that lead to differences in conclusions about effectiveness. The Ecuador case illustrates that

  5. Estimating the Counterfactual Impact of Conservation Programs on Land Cover Outcomes: The Role of Matching and Panel Regression Techniques.

    Directory of Open Access Journals (Sweden)

    Kelly W Jones

    Full Text Available Deforestation and conversion of native habitats continues to be the leading driver of biodiversity and ecosystem service loss. A number of conservation policies and programs are implemented--from protected areas to payments for ecosystem services (PES--to deter these losses. Currently, empirical evidence on whether these approaches stop or slow land cover change is lacking, but there is increasing interest in conducting rigorous, counterfactual impact evaluations, especially for many new conservation approaches, such as PES and REDD, which emphasize additionality. In addition, several new, globally available and free high-resolution remote sensing datasets have increased the ease of carrying out an impact evaluation on land cover change outcomes. While the number of conservation evaluations utilizing 'matching' to construct a valid control group is increasing, the majority of these studies use simple differences in means or linear cross-sectional regression to estimate the impact of the conservation program using this matched sample, with relatively few utilizing fixed effects panel methods--an alternative estimation method that relies on temporal variation in the data. In this paper we compare the advantages and limitations of (1 matching to construct the control group combined with differences in means and cross-sectional regression, which control for observable forms of bias in program evaluation, to (2 fixed effects panel methods, which control for observable and time-invariant unobservable forms of bias, with and without matching to create the control group. We then use these four approaches to estimate forest cover outcomes for two conservation programs: a PES program in Northeastern Ecuador and strict protected areas in European Russia. In the Russia case we find statistically significant differences across estimators--due to the presence of unobservable bias--that lead to differences in conclusions about effectiveness. The Ecuador case

  6. Scattering of the transverse magnetic modes from an abruptly ended strongly asymmetrical slab waveguide by an accelerated integral equation technique.

    Science.gov (United States)

    Manenkov, A B; Latsas, G P; Tigelis, L G

    2001-12-01

    We study the problem of the scattering of the first TM guided mode from an abruptly ended strongly asymmetrical slab waveguide by an improved iteration technique, which is based on the integral equation method with "accelerating" parameters. We demonstrate that the values of these parameters are related to the variational principle, and we save approximately 1-2 iterations compared with the case in which these parameters are not employed. The tangential electric-field distribution on the terminal plane, the reflection coefficient of the first TM guided mode, and the far-field radiation pattern are computed. Furthermore, a simple technique based on the Aitken extrapolation procedure is employed for faster computation of the higher-order solutions of the reflection coefficient. Numerical results are presented for several cases of abruptly ended waveguides, including systems with variational profile, while special attention is given to the far-field radiation pattern rotation and its explanation.

  7. A Miniaturized Dual-Mode Bandpass Filter Using Slot Spurline Technique

    Directory of Open Access Journals (Sweden)

    Haiwen Liu

    2013-01-01

    Full Text Available A miniaturized dual-mode bandpass filter (BPF with elliptic function response using slot spurline is designed in this paper. The slot spurline can not only splits the degenerate modes but also determine the type of filter characteristic (Chebyshev or elliptic. To miniaturize the resonator, four sagittate stubs are proposed. For demonstration purpose, a BPF operating at 5.75 GHz for WLAN application was designed, fabricated, and measured. The measured results are in good agreement with the full-wave simulation results.

  8. Matching theory

    CERN Document Server

    Plummer, MD

    1986-01-01

    This study of matching theory deals with bipartite matching, network flows, and presents fundamental results for the non-bipartite case. It goes on to study elementary bipartite graphs and elementary graphs in general. Further discussed are 2-matchings, general matching problems as linear programs, the Edmonds Matching Algorithm (and other algorithmic approaches), f-factors and vertex packing.

  9. Estimating the Counterfactual Impact of Conservation Programs on Land Cover Outcomes: The Role of Matching and Panel Regression Techniques

    Science.gov (United States)

    Jones, Kelly W.; Lewis, David J.

    2015-01-01

    Deforestation and conversion of native habitats continues to be the leading driver of biodiversity and ecosystem service loss. A number of conservation policies and programs are implemented—from protected areas to payments for ecosystem services (PES)—to deter these losses. Currently, empirical evidence on whether these approaches stop or slow land cover change is lacking, but there is increasing interest in conducting rigorous, counterfactual impact evaluations, especially for many new conservation approaches, such as PES and REDD, which emphasize additionality. In addition, several new, globally available and free high-resolution remote sensing datasets have increased the ease of carrying out an impact evaluation on land cover change outcomes. While the number of conservation evaluations utilizing ‘matching’ to construct a valid control group is increasing, the majority of these studies use simple differences in means or linear cross-sectional regression to estimate the impact of the conservation program using this matched sample, with relatively few utilizing fixed effects panel methods—an alternative estimation method that relies on temporal variation in the data. In this paper we compare the advantages and limitations of (1) matching to construct the control group combined with differences in means and cross-sectional regression, which control for observable forms of bias in program evaluation, to (2) fixed effects panel methods, which control for observable and time-invariant unobservable forms of bias, with and without matching to create the control group. We then use these four approaches to estimate forest cover outcomes for two conservation programs: a PES program in Northeastern Ecuador and strict protected areas in European Russia. In the Russia case we find statistically significant differences across estimators—due to the presence of unobservable bias—that lead to differences in conclusions about effectiveness. The Ecuador case

  10. Application of the failure modes and effects analysis technique to the emergency cooling system of an experimental nuclear power plant

    International Nuclear Information System (INIS)

    Conceicao Junior, Osmar; Silva, Antonio Teixeira e

    2009-01-01

    This study consists on the application of the failure modes and effects analysis (FMEA), a hazard identification and a risk assessment technique, to the emergency cooling system (ECS), of an experimental nuclear power plant. The choice of this technique was due to its detailed analysis of each component of the system, enabling the identification of all possible ways of failure and its related consequences (in order of importance), allowing the designer to improve the system, maximizing its security and reliability. Through the application of this methodology, it could be observed that the ECS is an intrinsically safe system, in spite of the modifications proposed. (author)

  11. Pre- and post-operative evaluation of pincer-type femoroacetabular impingement during squat using image-matching techniques: A case report.

    Science.gov (United States)

    Yoshimoto, Kensei; Hamai, Satoshi; Higaki, Hidehiko; Gondo, Hirotaka; Ikebe, Satoru; Nakashima, Yasuharu

    2018-01-01

    Although combined evaluation of hip joint kinematics and bone morphology is necessary for accurate assessment of femoroacetabular impingement (FAI), there are no report which evaluated hip kinematics of pincer-type FAI. The pre- and postoperative hip kinematics of a 46-year-old man, with a pincer-type FAI during squat were evaluated using image-matching techniques and the rim-neck distance was measured. Preoperative simulation of squatting was also performed using patient's bone models and healthy subject's kinematics data to detect the overlapping lesion between the acetabulum and the femur. Post-acetabuloplasty, right coxalgia during squat disappeared, and the Harris Hip Score improved from 79 to 92 at one year after surgery. Posterior pelvic tilt, femoral and hip flexion angle changed from 24.0°, 101.1°, and 70.8° to 23.3°, 92.6°, and 63.3°, respectively. The minimum rim-neck distance at maximum hip flexion improved from 1.8mm to 7.3mm. We could evaluate both of hip kinematics and morphology with image-matching techniques, and could visualize the clearance between the femoral head-neck junction and the acetabular rim. Image-matching techniques were clinically useful to assist surgeons in detecting the location of the impingement and confirming resection of the pincer lesion post-operatively. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  12. A versatile stereo photogrammetry based technique for measuring fracture mode displacements in structures

    DEFF Research Database (Denmark)

    Alvarado, Jonathan Shmueli; Eder, Martin Alexander; Tesauro, Angelo

    2015-01-01

    The measurement of fracture mode displacements in structures which are susceptible to cracking such as adhesive joints in composite components – is becoming increasingly important. Such measurements are essential for the understanding of the root causes for specific fracture damage types. Further...

  13. Direct and Inverse Techniques of Guided-Mode Resonance Filters Designs

    Science.gov (United States)

    Tibuleac, Sorin; Magnusson, Robert; Maldonado, Theresa A.; Zuffada, Cinzia

    1997-01-01

    Guided-mode resonances arise in single or multilayer waveguides where one or more homogeneous layers are replaced by diffraction gratings (Fig. 1.) The diffractive element enables an electromagnetic wave incident on a waveguide grating to be coupled to the waveguide modes supportable by the structure in the absence of the modulation (i.e. the difference between the high and low dielectric constants of the grating) at specific values of the wavelength and incident angle. The periodic modulation of the guide makes the structure leaky, preventing sustained propagation of modes in the waveguide and coupling the waves out into the substrate and cover. As the wavelength is varied around resonance a rapid variation in the intensities of the external propagating waves occurs. By selecting a grating period small enough to eliminate the higher-order propagating waves, an increase in the zero-order intensities up to 100% can result. The pronounced frequency selectivity of guided-mode resonances in dielectric waveguide gratings can be applied to design high-efficiency reflection and transmission filters [1-3].

  14. Flexible picosecond thulium-doped fiber laser using the active mode-locking technique.

    Science.gov (United States)

    Yin, Ke; Zhang, Bin; Yang, Weiqiang; Chen, He; Chen, Shengping; Hou, Jing

    2014-07-15

    An all-fiber actively mode-locked thulium-doped fiber laser (AML-TDFL) based on a 10 GHz bandwidth electro-optic intensity modulator (EOM) providing flexible picosecond pulses at 1980 nm is presented. The EOM is driven by electrical pulses rather than traditional sine-wave signals. The repetition rate of output pulses was 21.4 MHz at fundamental mode-locking, which could be scaled up to 1.498 GHz through the 70th order harmonic mode-locking, and the shortest measured output pulse width was 38 ps. Furthermore, the output pulse width could be tuned by either adjusting the modulation frequency with small detuning or changing the width of these driving electrical pulses without frequency detuning. In our work, the stability of these mode-locked pulses obtained from the AML-TDFL was superior; for instance, the measured supermode suppression ratio of 1.498 GHz pulses train was up to 48 dB.

  15. Application of mass spectrometric techniques to delineate the modes-of-action of anticancer metallodrugs

    NARCIS (Netherlands)

    Hartinger, Christian G.; Groessl, Michael; Meier, Samuel M.; Casini, Angela; Dyson, Paul J.

    2013-01-01

    Mass spectrometry (MS) has emerged as an important tool for studying anticancer metallodrugs in complex biological samples and for characterising their interactions with biomolecules and potential targets on a molecular level. The exact modes-of-action of these coordination compounds and especially

  16. Dynamic model updating based on strain mode shape and natural frequency using hybrid pattern search technique

    Science.gov (United States)

    Guo, Ning; Yang, Zhichun; Wang, Le; Ouyang, Yan; Zhang, Xinping

    2018-05-01

    Aiming at providing a precise dynamic structural finite element (FE) model for dynamic strength evaluation in addition to dynamic analysis. A dynamic FE model updating method is presented to correct the uncertain parameters of the FE model of a structure using strain mode shapes and natural frequencies. The strain mode shape, which is sensitive to local changes in structure, is used instead of the displacement mode for enhancing model updating. The coordinate strain modal assurance criterion is developed to evaluate the correlation level at each coordinate over the experimental and the analytical strain mode shapes. Moreover, the natural frequencies which provide the global information of the structure are used to guarantee the accuracy of modal properties of the global model. Then, the weighted summation of the natural frequency residual and the coordinate strain modal assurance criterion residual is used as the objective function in the proposed dynamic FE model updating procedure. The hybrid genetic/pattern-search optimization algorithm is adopted to perform the dynamic FE model updating procedure. Numerical simulation and model updating experiment for a clamped-clamped beam are performed to validate the feasibility and effectiveness of the present method. The results show that the proposed method can be used to update the uncertain parameters with good robustness. And the updated dynamic FE model of the beam structure, which can correctly predict both the natural frequencies and the local dynamic strains, is reliable for the following dynamic analysis and dynamic strength evaluation.

  17. POTENTIAL AND PITFALLS OF CHROMATOGRAPHIC TECHNIQUES AND DETECTION MODES IN SUBSTANCE IDENTIFICATION FOR SYSTEMATIC TOXICOLOGICAL ANALYSIS

    NARCIS (Netherlands)

    DEZEEUW, RA; HARTSTRA, J; FRANKE, JP

    1994-01-01

    The potential and the constraints of thin-layer chromatography (TLC), gas chromatography (GC) and high-performance liquid chromatography (HPLC) towards substance identification, together with their detection modes, are considered. The latter include colour reactions on the plate, molecular masses

  18. Comparison of self-written waveguide techniques and bulk index matching for low-loss polymer waveguide interconnects

    Science.gov (United States)

    Burrell, Derek; Middlebrook, Christopher

    2016-03-01

    Polymer waveguides (PWGs) are used within photonic interconnects as inexpensive and versatile substitutes for traditional optical fibers. The PWGs are typically aligned to silica-based optical fibers for coupling. An epoxide elastomer is then applied and cured at the interface for index matching and rigid attachment. Self-written waveguides (SWWs) are proposed as an alternative to further reduce connection insertion loss (IL) and alleviate marginal misalignment issues. Elastomer material is deposited after the initial alignment, and SWWs are formed by injecting ultraviolet (UV) light into the fiber or waveguide. The coupled UV light cures a channel between the two differing structures. A suitable cladding layer can be applied after development. Such factors as longitudinal gap distance, UV cure time, input power level, polymer material selection and choice of solvent affect the resulting SWWs. Experimental data are compared between purely index-matched samples and those with SWWs at the fiber-PWG interface. It is shown that < 1 dB IL per connection can be achieved by either method and results indicate lowest potential losses associated with a fine-tuned self-writing process. Successfully fabricated SWWs reduce overall processing time and enable an effectively continuous low-loss rigid interconnect.

  19. Application of the failure modes and effects analysis technique to theemergency cooling system of an experimental nuclear power plant

    International Nuclear Information System (INIS)

    Conceicao Junior, Osmar

    2009-01-01

    This study consists on the application of the Failure Modes and EffectsAnalysis (FMEA), a hazard identification and a risk assessment technique, tothe Emergency Cooling System (ECS) of an experimental nuclear power plant,which is responsible for mitigating the consequences of an eventual loss ofcoolant accident on the Pressurized Water Reactor (PWR). Such analysisintends to identify possible weaknesses on the design of the system andpropose some improvements in order to maximize its reliability. To achievethis goal a detailed study of the system was carried on (through itstechnical documentation), the correspondent reliability block diagram wasobtained, the FMEA analysis was executed and, finally, some suggestions werepresented. (author)

  20. Mode of Delivery: A Classroom Assessment Technique Comparison between Verbal and Non-Verbal Communication

    Science.gov (United States)

    Hogan, Andrea; Daw, Jolene

    2014-01-01

    This study explores how using Classroom Assessment Techniques (CATs) in phone conversations with students may help to clarify learning objectives and encourage active learning in distance education. For this study, research was collected from introductory undergraduate online courses at a university in the Southwest. Data was collected from three…

  1. Analytical study of nonlinear phase shift through stimulated Brillouin scattering in single mode fiber with the pump power recycling technique

    International Nuclear Information System (INIS)

    Al-Asadi, H A; Mahdi, M A; Bakar, A A A; Adikan, F R Mahamd

    2011-01-01

    We present a theoretical study of nonlinear phase shift through stimulated Brillouin scattering in single mode optical fiber. Analytical expressions describing the nonlinear phase shift for the pump and Stokes waves in the pump power recycling technique have been derived. The dependence of the nonlinear phase shift on the optical fiber length, the reflectivity of the optical mirror and the frequency detuning coefficient have been analyzed for different input pump power values. We found that with the recycling pump technique, the nonlinear phase shift due to stimulated Brillouin scattering reduced to less than 0.1 rad for 5 km optical fiber length and 0.65 reflectivity of the optical mirror, respectively, at an input pump power equal to 30 mW

  2. Characterization of failure modes in deep UV and deep green LEDs utilizing advanced semiconductor localization techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Tangyunyong, Paiboon; Miller, Mary A.; Cole, Edward Isaac, Jr.

    2012-03-01

    We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpret data acquired. We also describe a defect screening method based on a quick electrical measurement to determine whether defects should be present in the LEDs. We then describe the stress conditions that caused the devices to fail and how the TIVA/LIVA techniques were used to monitor the defect signals as the devices degraded and failed. We also describe the correlation between the initial defects and final degraded or failed state of the devices. Finally we show characterization results of the devices in the failed conditions and present preliminary theories as to why the devices failed for both the InGaN (green) and AlGaN (UV) LEDs.

  3. Effect of light sources and curing mode techniques on sorption, solubility and biaxial flexural strength of a composite resin.

    Science.gov (United States)

    Carvalho, Andreia Assis; Moreira, Francine do Couto Lima; Fonseca, Rodrigo Borges; Soares, Carlos José; Franco, Eduardo Batista; Souza, João Batista de; Lopes, Lawrence Gonzaga

    2012-01-01

    Adequate polymerization plays an important role on the longevity of the composite resin restorations. The aim of this study was to evaluate the effect of light-curing units, curing mode techniques and storage media on sorption, solubility and biaxial flexural strength (BFS) of a composite resin. Two hundred and forty specimens were made of one composite resin (Esthet-X) in a stainless steel mold (2 mm x 8 mm Ø), and divided into 24 groups (n=10) established according to the 4 study factors: light-curing units: quartz tungsten halogen (QTH) lamp and light-emitting diodes (LED); energy densities: 16 J/cm² and 20 J/cm²; curing modes: conventional (CM) and pulse-delay (PD); and permeants: deionized water and 75% ethanol for 28 days. Sorption and solubility tests were performed according to ISO 4049:2000 specifications. All specimens were then tested for BFS according to ASTM F394-78 specification. Data were analyzed by three-way ANOVA followed by Tukey, Kruskal-Wallis and Mann-Whitney tests (α=0.05). In general, no significant differences were found regarding sorption, solubility or BFS means for the light-curing units and curing modes (p>0.05). Only LED unit using 16 J/cm² and PD using 10 s produced higher sorption and solubility values than QTH. Otherwise, using CM (16 J/cm²), LED produced lower values of BFS than QTH (pcuring units using 16 and 20 J/cm² by CM and PD curing modes produced no influence on the sorption, solubility or BFS of the tested resin.

  4. A scatter-corrected list-mode reconstruction and a practical scatter/random approximation technique for dynamic PET imaging

    International Nuclear Information System (INIS)

    Cheng, J-C; Rahmim, Arman; Blinder, Stephan; Camborde, Marie-Laure; Raywood, Kelvin; Sossi, Vesna

    2007-01-01

    We describe an ordinary Poisson list-mode expectation maximization (OP-LMEM) algorithm with a sinogram-based scatter correction method based on the single scatter simulation (SSS) technique and a random correction method based on the variance-reduced delayed-coincidence technique. We also describe a practical approximate scatter and random-estimation approach for dynamic PET studies based on a time-averaged scatter and random estimate followed by scaling according to the global numbers of true coincidences and randoms for each temporal frame. The quantitative accuracy achieved using OP-LMEM was compared to that obtained using the histogram-mode 3D ordinary Poisson ordered subset expectation maximization (3D-OP) algorithm with similar scatter and random correction methods, and they showed excellent agreement. The accuracy of the approximated scatter and random estimates was tested by comparing time activity curves (TACs) as well as the spatial scatter distribution from dynamic non-human primate studies obtained from the conventional (frame-based) approach and those obtained from the approximate approach. An excellent agreement was found, and the time required for the calculation of scatter and random estimates in the dynamic studies became much less dependent on the number of frames (we achieved a nearly four times faster performance on the scatter and random estimates by applying the proposed method). The precision of the scatter fraction was also demonstrated for the conventional and the approximate approach using phantom studies

  5. Developing a novel technique for absolute measurements of the principal- and second-shock Hugoniots: a benchmark for the impedance-match methods

    Science.gov (United States)

    Gu, Yunjun; Zheng, Jun; Chen, Qifeng; Li, Chengjun; Li, Jiangtao; Chen, Zhiyun

    2017-06-01

    A novel diagnostics configuration was presented for performing the absolute measurements of the principal- and second-shock Hugoniots of the dense gaseous H2+D2 mixtures under multi-shock compression and probing their thermodynamic properties by a joint diagnostics of multi-channel optical pyrometer (MCOP), Doppler Pin System (DPS), and streak camera. This technique allowed the time-resolved optical radiation histories, interface velocity profiles, and time-resolved spectrum of the multi-compressed sample to be simultaneously measured in a single shot. The shock wave velocities and particle velocities under the former two shock compressions can be directly determined with the help of the above multiple detects instead of the impedance-match methods. So, absolute measurements of the principal- and second-shock Hugoniots for pre-compressed dense gaseous H2+D2 mixtures under multi-shock compression can be achieved, which provides a benchmark for the impedance-match measurement technique. Furthermore, the combination of multiple diagnostics also allows different experimental observables to be cross-checked, which reinforces the reliability of the experimental measurements.

  6. A Generic Current Mode Design for Multifunction Grounded Capacitor Filters Employing Log-Domain Technique

    Directory of Open Access Journals (Sweden)

    N. A. Shah

    2011-01-01

    Full Text Available A generic design (GD for realizing an nth order log-domain multifunction filter (MFF, which can yield four possible stable filter configurations, each offering simultaneously lowpass (LP, highpass (HP, and bandpass (BP frequency responses, is presented. The features of these filters are very simple, consisting of merely a few exponential transconductor cells and capacitors; all grounded elements, capable of absorbing the shunt parasitic capacitances, responses are electronically tuneable, and suitable for monolithic integration. Furthermore, being designed using log-domain technique, it offers all its advantages. As an example, 5th-order MFFs are designed in each case and their performances are evaluated through simulation. Lastly, a comparative study of the MFFs is also carried, which helps in selecting better high-order MFF for a given application.

  7. Assessment of mode of delivery and predictors of emergency caesarean section among women living with HIV in a matched-pair setting with women from the general population in Denmark, 2002-2014

    DEFF Research Database (Denmark)

    Ørbaek, M; Thorsteinsson, K; Helleberg, M

    2017-01-01

    OBJECTIVES: We aimed to assess mode of delivery and predictors of emergency caesarean section (EmCS) in women living with HIV (WLWH) in a matched-pair setting with women from the general population (WGP) in Denmark. Further, we analysed birth plan in WLWH. METHODS: All WLWH giving birth to live...... in the study. At delivery, all WLWH were on antiretroviral therapy and 85.6% had HIV RNA HIV-1 RNA copies/mL. Mean age was 32.7 years [95% confidence interval (CI) 32.1-33.2 years]. Mode of delivery differed significantly between WLWH and WGP [vaginal delivery, 33.4% versus 73.3%, respectively; elective...

  8. Non destructive technique for cracks detection by an eddy current in differential mode for steel frames

    Energy Technology Data Exchange (ETDEWEB)

    Harzalla, S., E-mail: harzallahozil@yahoo.fr; Chabaat, M., E-mail: mchabaat@yahoo.com [Built Environmental Research Laboratory, Civil Engineering Faculty, University of Sciences and Technology Houari Boumediene, B.P. 32 El Alia Bab-Ezzouar, Algiers 16111 (Algeria); Belgacem, F. Bin Muhammad, E-mail: fbmbelgacem@gmail.com [Department of Mathematics, Faculty of Basic Education, PAAET, Al-Aardhia (Kuwait)

    2014-12-10

    In this paper, a nondestructive technique is used as a tool to control cracks and microcracks in materials. A simulation by a numerical approach such as the finite element method is employed to detect cracks and eventually; to study their propagation using a crucial parameter such as the stress intensity factor. This approach has been used in the aircraft industry to control cracks. Besides, it makes it possible to highlight the defects of parts while preserving the integrity of the controlled products. On the other side, it is proven that the reliability of the control of defects gives convincing results for the improvement of the quality and the safety of the material. Eddy current testing (ECT) is a standard technique in industry for the detection of surface breaking flaws in magnetic materials such as steels. In this context, simulation tools can be used to improve the understanding of experimental signals, optimize the design of sensors or evaluate the performance of ECT procedures. CEA-LIST has developed for many years semi-analytical models embedded into the simulation platform CIVA dedicated to non-destructive testing. The developments presented herein address the case of flaws located inside a planar and magnetic medium. Simulation results are obtained through the application of the Volume Integral Method (VIM). When considering the ECT of a single flaw, a system of two differential equations is derived from Maxwell equations. The numerical resolution of the system is carried out using the classical Galerkin variant of the Method of Moments. Besides, a probe response is calculated by application of the Lorentz reciprocity theorem. Finally, the approach itself as well as comparisons between simulation results and measured data are presented.

  9. Non destructive technique for cracks detection by an eddy current in differential mode for steel frames

    International Nuclear Information System (INIS)

    Harzalla, S.; Chabaat, M.; Belgacem, F. Bin Muhammad

    2014-01-01

    In this paper, a nondestructive technique is used as a tool to control cracks and microcracks in materials. A simulation by a numerical approach such as the finite element method is employed to detect cracks and eventually; to study their propagation using a crucial parameter such as the stress intensity factor. This approach has been used in the aircraft industry to control cracks. Besides, it makes it possible to highlight the defects of parts while preserving the integrity of the controlled products. On the other side, it is proven that the reliability of the control of defects gives convincing results for the improvement of the quality and the safety of the material. Eddy current testing (ECT) is a standard technique in industry for the detection of surface breaking flaws in magnetic materials such as steels. In this context, simulation tools can be used to improve the understanding of experimental signals, optimize the design of sensors or evaluate the performance of ECT procedures. CEA-LIST has developed for many years semi-analytical models embedded into the simulation platform CIVA dedicated to non-destructive testing. The developments presented herein address the case of flaws located inside a planar and magnetic medium. Simulation results are obtained through the application of the Volume Integral Method (VIM). When considering the ECT of a single flaw, a system of two differential equations is derived from Maxwell equations. The numerical resolution of the system is carried out using the classical Galerkin variant of the Method of Moments. Besides, a probe response is calculated by application of the Lorentz reciprocity theorem. Finally, the approach itself as well as comparisons between simulation results and measured data are presented

  10. Comparison of Matching Pursuit Algorithm with Other Signal Processing Techniques for Computation of the Time-Frequency Power Spectrum of Brain Signals.

    Science.gov (United States)

    Chandran K S, Subhash; Mishra, Ashutosh; Shirhatti, Vinay; Ray, Supratim

    2016-03-23

    Signals recorded from the brain often show rhythmic patterns at different frequencies, which are tightly coupled to the external stimuli as well as the internal state of the subject. In addition, these signals have very transient structures related to spiking or sudden onset of a stimulus, which have durations not exceeding tens of milliseconds. Further, brain signals are highly nonstationary because both behavioral state and external stimuli can change on a short time scale. It is therefore essential to study brain signals using techniques that can represent both rhythmic and transient components of the signal, something not always possible using standard signal processing techniques such as short time fourier transform, multitaper method, wavelet transform, or Hilbert transform. In this review, we describe a multiscale decomposition technique based on an over-complete dictionary called matching pursuit (MP), and show that it is able to capture both a sharp stimulus-onset transient and a sustained gamma rhythm in local field potential recorded from the primary visual cortex. We compare the performance of MP with other techniques and discuss its advantages and limitations. Data and codes for generating all time-frequency power spectra are provided. Copyright © 2016 the authors 0270-6474/16/363399-10$15.00/0.

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

    Science.gov (United States)

    Schunk, Gerhard; Fürst, Josef U; Förtsch, Michael; Strekalov, Dmitry V; Vogl, Ulrich; Sedlmeir, Florian; Schwefel, Harald G L; Leuchs, Gerd; Marquardt, Christoph

    2014-12-15

    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 WGMRs. The radial mode numbers q and the angular mode numbers p = ℓ-m are identified and labeled via far-field imaging. The polar mode numbers ℓ are determined unambiguously by fitting the frequency differences between individual whispering gallery modes (WGMs). This allows for the accurate determination of the geometry and the refractive index at different temperatures of the WGMR. For future applications in classical and quantum optics, this mode analysis enables one to control the narrow-band phase-matching conditions in nonlinear processes such as second-harmonic generation or parametric down-conversion.

  12. Evaluation of hydrocephalus patients with 3D-SPACE technique using variant FA mode at 3T.

    Science.gov (United States)

    Algin, Oktay

    2017-09-26

    The major advantages of three-dimensional sampling perfection with application optimized contrasts using different flip-angle evolution (3D-SPACE) technique are its high resistance to artifacts that occurs as a result of radiofrequency or static field, the ability of providing images with sub-millimeter voxel size which allows obtaining reformatted images in any plane due to isotropic three-dimensional data with lower specific absorption rate values. That is crucial during examination of cerebrospinal-fluid containing complex structures, and the acquisition time, which is approximately 5 min for scanning of entire cranium. Recent data revealed that T2-weighted (T2W) 3D-SPACE with variant flip-angle mode (VFAM) imaging allows fast and accurate evaluation of the hydrocephalus patients during both pre- and post-operative period for monitoring the treatment. For a better assessment of these patients; radiologists and neurosurgeons should be aware of the details and implications regarding to the 3D-SPACE technique, and they should follow the updates in this field. There could be a misconception about the difference between T2W-VFAM and routine heavily T2W 3D-SPACE images. T2W 3D-SPACE with VFAM imaging is only a subtype of 3D-SPACE technique. In this review, we described the details of T2W 3D-SPACE with VFAM imaging and comprehensively reviewed its recent applications.

  13. Carotid artery wall motion analysis from B-mode ultrasound using adaptive block matching: in silico evaluation and in vivo application.

    Science.gov (United States)

    Gastounioti, A; Golemati, S; Stoitsis, J S; Nikita, K S

    2013-12-21

    Valid risk stratification for carotid atherosclerotic plaques represents a crucial public health issue toward preventing fatal cerebrovascular events. Although motion analysis (MA) provides useful information about arterial wall dynamics, the identification of motion-based risk markers remains a significant challenge. Considering that the ability of a motion estimator (ME) to handle changes in the appearance of motion targets has a major effect on accuracy in MA, we investigated the potential of adaptive block matching (ABM) MEs, which consider changes in image intensities over time. To assure the validity in MA, we optimized and evaluated the ABM MEs in the context of a specially designed in silico framework. ABM(FIRF2), which takes advantage of the periodicity characterizing the arterial wall motion, was the most effective ABM algorithm, yielding a 47% accuracy increase with respect to the conventional block matching. The in vivo application of ABM(FIRF2) revealed five potential risk markers: low movement amplitude of the normal part of the wall adjacent to the plaques in the radial (RMA(PWL)) and longitudinal (LMA(PWL)) directions, high radial motion amplitude of the plaque top surface (RMA(PTS)), and high relative movement, expressed in terms of radial strain (RSI(PL)) and longitudinal shear strain (LSSI(PL)), between plaque top and bottom surfaces. The in vivo results were reproduced by OF(LK(WLS)) and ABM(KF-K2), MEs previously proposed by the authors and with remarkable in silico performances, thereby reinforcing the clinical values of the markers and the potential of those MEs. Future in vivo studies will elucidate with confidence the full potential of the markers.

  14. Carotid artery wall motion analysis from B-mode ultrasound using adaptive block matching: in silico evaluation and in vivo application

    International Nuclear Information System (INIS)

    Gastounioti, A; Stoitsis, J S; Nikita, K S; Golemati, S

    2013-01-01

    Valid risk stratification for carotid atherosclerotic plaques represents a crucial public health issue toward preventing fatal cerebrovascular events. Although motion analysis (MA) provides useful information about arterial wall dynamics, the identification of motion-based risk markers remains a significant challenge. Considering that the ability of a motion estimator (ME) to handle changes in the appearance of motion targets has a major effect on accuracy in MA, we investigated the potential of adaptive block matching (ABM) MEs, which consider changes in image intensities over time. To assure the validity in MA, we optimized and evaluated the ABM MEs in the context of a specially designed in silico framework. ABM FIRF2 , which takes advantage of the periodicity characterizing the arterial wall motion, was the most effective ABM algorithm, yielding a 47% accuracy increase with respect to the conventional block matching. The in vivo application of ABM FIRF2 revealed five potential risk markers: low movement amplitude of the normal part of the wall adjacent to the plaques in the radial (RMA PWL ) and longitudinal (LMA PWL ) directions, high radial motion amplitude of the plaque top surface (RMA PTS ), and high relative movement, expressed in terms of radial strain (RSI PL ) and longitudinal shear strain (LSSI PL ), between plaque top and bottom surfaces. The in vivo results were reproduced by OF LK(WLS) and ABM KF-K2 , MEs previously proposed by the authors and with remarkable in silico performances, thereby reinforcing the clinical values of the markers and the potential of those MEs. Future in vivo studies will elucidate with confidence the full potential of the markers. (paper)

  15. An automated patient recognition method based on an image-matching technique using previous chest radiographs in the picture archiving and communication system environment

    International Nuclear Information System (INIS)

    Morishita, Junji; Katsuragawa, Shigehiko; Kondo, Keisuke; Doi, Kunio

    2001-01-01

    An automated patient recognition method for correcting 'wrong' chest radiographs being stored in a picture archiving and communication system (PACS) environment has been developed. The method is based on an image-matching technique that uses previous chest radiographs. For identification of a 'wrong' patient, the correlation value was determined for a previous image of a patient and a new, current image of the presumed corresponding patient. The current image was shifted horizontally and vertically and rotated, so that we could determine the best match between the two images. The results indicated that the correlation values between the current and previous images for the same, 'correct' patients were generally greater than those for different, 'wrong' patients. Although the two histograms for the same patient and for different patients overlapped at correlation values greater than 0.80, most parts of the histograms were separated. The correlation value was compared with a threshold value that was determined based on an analysis of the histograms of correlation values obtained for the same patient and for different patients. If the current image is considered potentially to belong to a 'wrong' patient, then a warning sign with the probability for a 'wrong' patient is provided to alert radiology personnel. Our results indicate that at least half of the 'wrong' images in our database can be identified correctly with the method described in this study. The overall performance in terms of a receiver operating characteristic curve showed a high performance of the system. The results also indicate that some readings of 'wrong' images for a given patient in the PACS environment can be prevented by use of the method we developed. Therefore an automated warning system for patient recognition would be useful in correcting 'wrong' images being stored in the PACS environment

  16. Radiological and clinical pneumonitis after stereotactic lung radiotherapy: a matched analysis of three-dimensional conformal and volumetric-modulated arc therapy techniques.

    Science.gov (United States)

    Palma, David A; Senan, Suresh; Haasbeek, Cornelis J A; Verbakel, Wilko F A R; Vincent, Andrew; Lagerwaard, Frank

    2011-06-01

    Lung fibrosis is common after stereotactic body radiotherapy (SBRT) for lung tumors, but the influence of treatment technique on rates of clinical and radiological pneumonitis is not well described. After implementing volumetric modulated arc therapy (RapidArc [RA]; Varian Medical Systems, Palo Alto, CA) for SBRT, we scored the early pulmonary changes seen with arc and conventional three-dimensional SBRT (3D-CRT). Twenty-five SBRT patients treated with RA were matched 1:2 with 50 SBRT patients treated with 3D-CRT. Dose fractionations were based on a risk-adapted strategy. Clinical pneumonitis was scored using Common Terminology Criteria for Adverse Events version 3.0. Acute radiological changes 3 months posttreatment were scored by three blinded observers. Relationships among treatment type, baseline factors, and outcomes were assessed using Spearman's correlation, Cochran-Mantel-Haenszel tests, and logistic regression. The RA and 3D-CRT groups were well matched. Forty-three patients (57%) had radiological pneumonitis 3 months after treatment. Twenty-eight patients (37%) had computed tomography (CT) findings of patchy or diffuse consolidation, and 15 patients (20%) had ground-glass opacities only. Clinical pneumonitis was uncommon, and no differences were seen between 3D-CRT vs. RA patients in rates of grade 2/3 clinical pneumonitis (6% vs. 4%, respectively; p = 0.99), moderate/severe radiological changes (24% vs. 36%, respectively, p = 0.28), or patterns of CT changes (p = 0.47). Radiological severity scores were associated with larger planning target volumes (p = 0.09) and extended fractionation (p = 0.03). Radiological changes after lung SBRT are common with both approaches, but no differences in early clinical or radiological findings were observed after RA. Longer follow-up will be required to exclude late changes. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Combining QSAR Modeling and Text-Mining Techniques to Link Chemical Structures and Carcinogenic Modes of Action.

    Science.gov (United States)

    Papamokos, George; Silins, Ilona

    2016-01-01

    There is an increasing need for new reliable non-animal based methods to predict and test toxicity of chemicals. Quantitative structure-activity relationship (QSAR), a computer-based method linking chemical structures with biological activities, is used in predictive toxicology. In this study, we tested the approach to combine QSAR data with literature profiles of carcinogenic modes of action automatically generated by a text-mining tool. The aim was to generate data patterns to identify associations between chemical structures and biological mechanisms related to carcinogenesis. Using these two methods, individually and combined, we evaluated 96 rat carcinogens of the hematopoietic system, liver, lung, and skin. We found that skin and lung rat carcinogens were mainly mutagenic, while the group of carcinogens affecting the hematopoietic system and the liver also included a large proportion of non-mutagens. The automatic literature analysis showed that mutagenicity was a frequently reported endpoint in the literature of these carcinogens, however, less common endpoints such as immunosuppression and hormonal receptor-mediated effects were also found in connection with some of the carcinogens, results of potential importance for certain target organs. The combined approach, using QSAR and text-mining techniques, could be useful for identifying more detailed information on biological mechanisms and the relation with chemical structures. The method can be particularly useful in increasing the understanding of structure and activity relationships for non-mutagens.

  18. Development of a computerized method for identifying the posteroanterior and lateral views of chest radiographs by use of a template matching technique

    International Nuclear Information System (INIS)

    Arimura, Hidetaka; Katsuragawa, Shigehiko; Li Qiang; Ishida, Takayuki; Doi, Kunio

    2002-01-01

    In picture archiving and communications systems (PACS) or digital archiving systems, the information on the posteroanterior (PA) and lateral views for chest radiographs is often not recorded or is recorded incorrectly. However, it is necessary to identify the PA or lateral view correctly and automatically for quantitative analysis of chest images for computer-aided diagnosis. Our purpose in this study was to develop a computerized method for correctly identifying either PA or lateral views of chest radiographs. Our approach is to examine the similarity of a chest image with templates that represent the average chest images of the PA or lateral view for various types of patients. By use of a template matching technique with nine template images for patients of different size in two steps, correlation values were obtained for determining whether a chest image is either a PA or a lateral view. The templates for PA and lateral views were prepared from 447 PA and 200 lateral chest images. For a validation test, this scheme was applied to 1,000 test images consisting of 500 PA and 500 lateral chest radiographs, which are different from training cases. In the first step, 924 (92.4%) of the cases were correctly identified by comparison of the correlation values obtained with the three templates for medium-size patients. In the second step, the correlation values with the six templates for small and large patients were compared, and all of the remaining unidentifiable cases were identified correctly

  19. SU-E-I-74: Image-Matching Technique of Computed Tomography Images for Personal Identification: A Preliminary Study Using Anthropomorphic Chest Phantoms

    International Nuclear Information System (INIS)

    Matsunobu, Y; Shiotsuki, K; Morishita, J

    2015-01-01

    Purpose: Fingerprints, dental impressions, and DNA are used to identify unidentified bodies in forensic medicine. Cranial Computed tomography (CT) images and/or dental radiographs are also used for identification. Radiological identification is important, particularly in the absence of comparative fingerprints, dental impressions, and DNA samples. The development of an automated radiological identification system for unidentified bodies is desirable. We investigated the potential usefulness of bone structure for matching chest CT images. Methods: CT images of three anthropomorphic chest phantoms were obtained on different days in various settings. One of the phantoms was assumed to be an unidentified body. The bone image and the bone image with soft tissue (BST image) were extracted from the CT images. To examine the usefulness of the bone image and/or the BST image, the similarities between the two-dimensional (2D) or threedimensional (3D) images of the same and different phantoms were evaluated in terms of the normalized cross-correlation value (NCC). Results: For the 2D and 3D BST images, the NCCs obtained from the same phantom assumed to be an unidentified body (2D, 0.99; 3D, 0.93) were higher than those for the different phantoms (2D, 0.95 and 0.91; 3D, 0.89 and 0.80). The NCCs for the same phantom (2D, 0.95; 3D, 0.88) were greater compared to those of the different phantoms (2D, 0.61 and 0.25; 3D, 0.23 and 0.10) for the bone image. The difference in the NCCs between the same and different phantoms tended to be larger for the bone images than for the BST images. These findings suggest that the image-matching technique is more useful when utilizing the bone image than when utilizing the BST image to identify different people. Conclusion: This preliminary study indicated that evaluating the similarity of bone structure in 2D and 3D images is potentially useful for identifying of an unidentified body

  20. SU-E-I-74: Image-Matching Technique of Computed Tomography Images for Personal Identification: A Preliminary Study Using Anthropomorphic Chest Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Matsunobu, Y; Shiotsuki, K [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Morishita, J [Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, Fukuoka, JP (Japan)

    2015-06-15

    Purpose: Fingerprints, dental impressions, and DNA are used to identify unidentified bodies in forensic medicine. Cranial Computed tomography (CT) images and/or dental radiographs are also used for identification. Radiological identification is important, particularly in the absence of comparative fingerprints, dental impressions, and DNA samples. The development of an automated radiological identification system for unidentified bodies is desirable. We investigated the potential usefulness of bone structure for matching chest CT images. Methods: CT images of three anthropomorphic chest phantoms were obtained on different days in various settings. One of the phantoms was assumed to be an unidentified body. The bone image and the bone image with soft tissue (BST image) were extracted from the CT images. To examine the usefulness of the bone image and/or the BST image, the similarities between the two-dimensional (2D) or threedimensional (3D) images of the same and different phantoms were evaluated in terms of the normalized cross-correlation value (NCC). Results: For the 2D and 3D BST images, the NCCs obtained from the same phantom assumed to be an unidentified body (2D, 0.99; 3D, 0.93) were higher than those for the different phantoms (2D, 0.95 and 0.91; 3D, 0.89 and 0.80). The NCCs for the same phantom (2D, 0.95; 3D, 0.88) were greater compared to those of the different phantoms (2D, 0.61 and 0.25; 3D, 0.23 and 0.10) for the bone image. The difference in the NCCs between the same and different phantoms tended to be larger for the bone images than for the BST images. These findings suggest that the image-matching technique is more useful when utilizing the bone image than when utilizing the BST image to identify different people. Conclusion: This preliminary study indicated that evaluating the similarity of bone structure in 2D and 3D images is potentially useful for identifying of an unidentified body.

  1. Matching Organs

    Science.gov (United States)

    ... to know FAQ Living donation What is living donation? Organs Types Being a living donor First steps Being ... brochures What Every Patient Needs to Know Living Donation Multiple Listing Visit UNOS Store Learn more How organs are matched How to become a living donor ...

  2. A Riding-through Technique for Seamless Transition between Islanded and Grid-Connected Modes of Droop-Controlled Inverters

    DEFF Research Database (Denmark)

    Hu, Shang-hung; Lee, Tzung-Lin; Kuo, Chun-Yi

    2016-01-01

    This paper presents a seamless transition method for a droop-controlled inverter. The droop control is suitable to make the inverter work as a voltage source in both islanded and grid-connected modes, however, the transfer between theses modes can result in a big inrush current that may damage...... a smooth transition between them, requiring neither synchronization signals nor grid-side information. The control algorithm and design procedure are presented. Experimental results from a laboratory prototype validate the effectiveness of the proposed method....... the system. The proposed method allows the droop-controlled inverter to improve the transient response when transferring between modes, by detecting the inrush current, activating a current control loop during transients, and then transferring back to droop-controlled mode smoothly by using a virtual...

  3. Spectral matching techniques (SMTs) and automated cropland classification algorithms (ACCAs) for mapping croplands of Australia using MODIS 250-m time-series (2000–2015) data

    Science.gov (United States)

    Teluguntla, Pardhasaradhi G.; Thenkabail, Prasad S.; Xiong, Jun N.; Gumma, Murali Krishna; Congalton, Russell G.; Oliphant, Adam; Poehnelt, Justin; Yadav, Kamini; Rao, Mahesh N.; Massey, Richard

    2017-01-01

    Mapping croplands, including fallow areas, are an important measure to determine the quantity of food that is produced, where they are produced, and when they are produced (e.g. seasonality). Furthermore, croplands are known as water guzzlers by consuming anywhere between 70% and 90% of all human water use globally. Given these facts and the increase in global population to nearly 10 billion by the year 2050, the need for routine, rapid, and automated cropland mapping year-after-year and/or season-after-season is of great importance. The overarching goal of this study was to generate standard and routine cropland products, year-after-year, over very large areas through the use of two novel methods: (a) quantitative spectral matching techniques (QSMTs) applied at continental level and (b) rule-based Automated Cropland Classification Algorithm (ACCA) with the ability to hind-cast, now-cast, and future-cast. Australia was chosen for the study given its extensive croplands, rich history of agriculture, and yet nonexistent routine yearly generated cropland products using multi-temporal remote sensing. This research produced three distinct cropland products using Moderate Resolution Imaging Spectroradiometer (MODIS) 250-m normalized difference vegetation index 16-day composite time-series data for 16 years: 2000 through 2015. The products consisted of: (1) cropland extent/areas versus cropland fallow areas, (2) irrigated versus rainfed croplands, and (3) cropping intensities: single, double, and continuous cropping. An accurate reference cropland product (RCP) for the year 2014 (RCP2014) produced using QSMT was used as a knowledge base to train and develop the ACCA algorithm that was then applied to the MODIS time-series data for the years 2000–2015. A comparison between the ACCA-derived cropland products (ACPs) for the year 2014 (ACP2014) versus RCP2014 provided an overall agreement of 89.4% (kappa = 0.814) with six classes: (a) producer’s accuracies varying

  4. Three-dimensional analysis of accuracy of patient-matched instrumentation in total knee arthroplasty: Evaluation of intraoperative techniques and postoperative alignment.

    Science.gov (United States)

    Kuwashima, Umito; Mizu-Uchi, Hideki; Okazaki, Ken; Hamai, Satoshi; Akasaki, Yukio; Murakami, Koji; Nakashima, Yasuharu

    2017-11-01

    It is questionable that the accuracies of patient-matched instrumentation (PMI) have been controversial, even though many surgeons follow manufacturers' recommendations. The purpose of this study was to evaluate the accuracy of intraoperative procedures and the postoperative alignment of the femoral side using PMI with 3-dimensional (3D) analysis. Eighteen knees that underwent total knee arthroplasty using MRI-based PMI were assessed. Intraoperative alignment and bone resection errors of the femoral side were evaluated with a CT-based navigation system. A conventional adjustable guide was used to compare cartilage data with that derived by PMI intraoperatively. Postoperative alignment was assessed using a 3D coordinate system with a computer-assisted design software. We also measured the postoperative alignments using conventional alignment guides with the 3D evaluation. Intraoperative coronal alignment with PMI was 90.9° ± 1.6°. Seventeen knees (94.4%) were within 3° of the optimal alignment. Intraoperative rotational alignment of the femoral guide position of PMI was 0.2° ± 1.6°compared with the adjustable guide, with 17 knees (94.4%) differing by 3° or less between the two methods. Maximum differences in coronal and rotation alignment before and after bone cutting were 2.0° and 2.8°, respectively. Postoperative coronal and rotational alignments were 89.4° ± 1.8° and -1.1° ± 1.3°, respectively. In both alignments, 94.4% of cases were within 3° of the optimal value. The PMI group had less outliers than conventional group in rotational alignment (p = 0.018). Our 3D analysis provided evidence that PMI system resulted in reasonably satisfactory alignments both intraoperatively and postoperatively. Surgeons should be aware that certain surgical techniques including bone cutting, and the associated errors may affect postoperative alignment despite accurate PMI positioning. Copyright © 2017 The Japanese Orthopaedic Association. Published by

  5. The investigation of trapped thickness shear modes in a contoured AT-cut quartz plate using the power series expansion technique

    Science.gov (United States)

    Li, Peng; Jin, Feng

    2018-01-01

    The dynamic model about the anti-plane vibration of a contoured quartz plate with thickness changing continuously is established by ignoring the effect of small elastic constant c 56. The governing equation is solved using the power series expansion technique, and the trapped thickness shear modes caused by bulge thickness are revealed. Theoretically, the proposed method is more general, which can be capable of handling various thickness profiles defined mathematically. After the convergence of the series is demonstrated and the correctness is numerically validated with the aid of finite element method results, systematic parametric studies are subsequently carried out to quantify the effects of the geometry parameter upon the trapped modes, including resonant frequency and mode shape. After that, the band structures of thickness shear waves propagation in a periodically contoured quartz plate, as well as the power transmission spectra, are obtained based on the power series expansion technique. It is revealed that broad stop bands below cut-off frequency exist owing to the trapped modes excited by the geometry inhomogeneity, which has little relationship with the structural periodicity, and its physical mechanism is different from the Bragg scattering effect. The outcome is widely applicable, and can be utilized to provide theoretical and practical guidance for the design and manufacturing of quartz resonators and wave filters.

  6. Density perturbation mode structure of high frequency compressional and global Alfvén eigenmodes in the National Spherical Torus Experiment using a novel reflectometer analysis technique

    Science.gov (United States)

    Crocker, N. A.; Kubota, S.; Peebles, W. A.; Rhodes, T. L.; Fredrickson, E. D.; Belova, E.; Diallo, A.; LeBlanc, B. P.; Sabbagh, S. A.

    2018-01-01

    Reflectometry measurements of compressional (CAE) and global (GAE) Alfvén eigenmodes are analyzed to obtain the amplitude and spatial structure of the density perturbations associated with the modes. A novel analysis technique developed for this purpose is presented. The analysis also naturally yields the amplitude and spatial structure of the density contour radial displacement, which is found to be 2–4 times larger than the value estimated directly from the reflectometer measurements using the much simpler ‘mirror approximation’. The modes were driven by beam ions in a high power (6 MW) neutral beam heated H-mode discharge (#141398) in the National Spherical Torus Experiment. The results of the analysis are used to assess the contribution of the modes to core energy transport and ion heating. The total displacement amplitude of the modes, which is shown to be larger than previously estimated (Crocker et al 2013 Nucl. Fusion 53 43017), is compared to the predicted threshold (Gorelenkov et al 2010 Nucl. Fusion 50 84012) for the anomalously high heat diffusion inferred from transport modeling in similar NSTX discharges. The results of the analysis also have strong implications for the energy transport via coupling of CAEs to kinetic Alfvén waves seen in simulations with the Hybrid MHD code (Belova et al 2015 Phys. Rev. Lett. 115 15001). Finally, the amplitudes of the observed CAEs fall well below the threshold for causing significant ion heating by stochastic velocity space diffusion (Gates et al 2001 Phys. Rev. Lett. 87 205003).

  7. Review og pattern matching approaches

    DEFF Research Database (Denmark)

    Manfaat, D.; Duffy, Alex; Lee, B. S.

    1996-01-01

    This paper presents a review of pattern matching techniques. The application areas for pattern matching are extensive, ranging from CAD systems to chemical analysis and from manufacturing to image processing. Published techniques and methods are classified and assessed within the context of three...... key issues: pattern classes, similiarity types and mathing methods. It has been shown that the techniques and approaches are as diverse and varied as the applications....

  8. Matched-Filter Thermography

    Directory of Open Access Journals (Sweden)

    Nima Tabatabaei

    2018-04-01

    Full Text Available Conventional infrared thermography techniques, including pulsed and lock-in thermography, have shown great potential for non-destructive evaluation of broad spectrum of materials, spanning from metals to polymers to biological tissues. However, performance of these techniques is often limited due to the diffuse nature of thermal wave fields, resulting in an inherent compromise between inspection depth and depth resolution. Recently, matched-filter thermography has been introduced as a means for overcoming this classic limitation to enable depth-resolved subsurface thermal imaging and improving axial/depth resolution. This paper reviews the basic principles and experimental results of matched-filter thermography: first, mathematical and signal processing concepts related to matched-fileting and pulse compression are discussed. Next, theoretical modeling of thermal-wave responses to matched-filter thermography using two categories of pulse compression techniques (linear frequency modulation and binary phase coding are reviewed. Key experimental results from literature demonstrating the maintenance of axial resolution while inspecting deep into opaque and turbid media are also presented and discussed. Finally, the concept of thermal coherence tomography for deconvolution of thermal responses of axially superposed sources and creation of depth-selective images in a diffusion-wave field is reviewed.

  9. Probabilistic estimation of splitting coefficients of normal modes of the Earth, and their uncertainties, using an autoregressive technique

    Science.gov (United States)

    Pachhai, S.; Masters, G.; Laske, G.

    2017-12-01

    Earth's normal-mode spectra are crucial to studying the long wavelength structure of the Earth. Such observations have been used extensively to estimate "splitting coefficients" which, in turn, can be used to determine the three-dimensional velocity and density structure. Most past studies apply a non-linear iterative inversion to estimate the splitting coefficients which requires that the earthquake source is known. However, it is challenging to know the source details, particularly for big events as used in normal-mode analyses. Additionally, the final solution of the non-linear inversion can depend on the choice of damping parameter and starting model. To circumvent the need to know the source, a two-step linear inversion has been developed and successfully applied to many mantle and core sensitive modes. The first step takes combinations of the data from a single event to produce spectra known as "receiver strips". The autoregressive nature of the receiver strips can then be used to estimate the structure coefficients without the need to know the source. Based on this approach, we recently employed a neighborhood algorithm to measure the splitting coefficients for an isolated inner-core sensitive mode (13S2). This approach explores the parameter space efficiently without any need of regularization and finds the structure coefficients which best fit the observed strips. Here, we implement a Bayesian approach to data collected for earthquakes from early 2000 and more recent. This approach combines the data (through likelihood) and prior information to provide rigorous parameter values and their uncertainties for both isolated and coupled modes. The likelihood function is derived from the inferred errors of the receiver strips which allows us to retrieve proper uncertainties. Finally, we apply model selection criteria that balance the trade-offs between fit (likelihood) and model complexity to investigate the degree and type of structure (elastic and anelastic

  10. Testing techniques and comparisons between theory and test for vibration modes of ring stiffened truncated-cone shells.

    Science.gov (United States)

    Naumann, E. C.

    1972-01-01

    Vibration tests were carried out on truncated-cone shells with widely spaced ring stiffeners. The models were excited by an air shaker for LF modes and by small electrodynamic shakers for HF modes. The Novozhilov thin shell theory according to which a ring is an assembly of an arbitrary number of segments, each being a short truncated-cone shell of uniform thickness, is used in the analysis of the results. A mobile, noncontacting, displacement-sensitive sensor system developed by the author was used in the tests. Tests results are given for a free-free 60-deg cone and for a clamped-free 60-deg cone. The tests are characterized as having considerable value for the classification of prevalent multimode responses in shells of this type.

  11. Robust control of an industrial boiler system; a comparison between two approaches: Sliding mode control and H∞ technique

    International Nuclear Information System (INIS)

    Moradi, Hamed; Bakhtiari-Nejad, Firooz; Saffar-Avval, Majid

    2009-01-01

    To achieve a good performance of the utility boiler, dynamic variables such as drum pressure, steam temperature and water level of drum must be controlled. In this paper, a linear time invariant (LTI) model of a boiler system is considered in which the input variables are feed-water and fuel mass rates. However this dynamic model may associate with uncertainties. With considering the uncertainties of the dynamic model, a sliding mode controller is designed. After representation of the uncertain dynamic system in general control configuration and modelling the parametric uncertainties, nominal performance, robust stability and robust performance are analyzed by the concept of structured singular value μ. Using an algorithm for μ-analysis and applying an inversed-base controller, robust stability and nominal performance are guaranteed but robust performance is not satisfied. Finally, an optimal robust controller is designed based on μ-synthesis with DK-iteration algorithm. Both optimal robust and sliding mode controllers guarantee robust performance of the system against the uncertainties and result in desired time responses of the output variables. By applying H ∞ robust control, system tracks the desire reference inputs in a less time and with smoother time responses. However, less control efforts, feedwater and fuel mass rates, are needed when the sliding mode controller is applied.

  12. Reliability and failure modes of implant-supported zirconium-oxide fixed dental prostheses related to veneering techniques

    Science.gov (United States)

    Baldassarri, Marta; Zhang, Yu; Thompson, Van P.; Rekow, Elizabeth D.; Stappert, Christian F. J.

    2011-01-01

    Summary Objectives To compare fatigue failure modes and reliability of hand-veneered and over-pressed implant-supported three-unit zirconium-oxide fixed-dental-prostheses(FDPs). Methods Sixty-four custom-made zirconium-oxide abutments (n=32/group) and thirty-two zirconium-oxide FDP-frameworks were CAD/CAM manufactured. Frameworks were veneered with hand-built up or over-pressed porcelain (n=16/group). Step-stress-accelerated-life-testing (SSALT) was performed in water applying a distributed contact load at the buccal cusp-pontic-area. Post failure examinations were carried out using optical (polarized-reflected-light) and scanning electron microscopy (SEM) to visualize crack propagation and failure modes. Reliability was compared using cumulative-damage step-stress analysis (Alta-7-Pro, Reliasoft). Results Crack propagation was observed in the veneering porcelain during fatigue. The majority of zirconium-oxide FDPs demonstrated porcelain chipping as the dominant failure mode. Nevertheless, fracture of the zirconium-oxide frameworks was also observed. Over-pressed FDPs failed earlier at a mean failure load of 696 ± 149 N relative to hand-veneered at 882 ± 61 N (profile I). Weibull-stress-number of cycles-unreliability-curves were generated. The reliability (2-sided at 90% confidence bounds) for a 400N load at 100K cycles indicated values of 0.84 (0.98-0.24) for the hand-veneered FDPs and 0.50 (0.82-0.09) for their over-pressed counterparts. Conclusions Both zirconium-oxide FDP systems were resistant under accelerated-life-time-testing. Over-pressed specimens were more susceptible to fatigue loading with earlier veneer chipping. PMID:21557985

  13. In-situ growth mode control of AlN on SiC substrate by sublimation closed space technique

    Science.gov (United States)

    Dojima, Daichi; Ashida, Koji; Kaneko, Tadaaki

    2018-02-01

    For the growth of AlN single crystal with large diameter and low dislocation density on SiC substrate by physical vapor transport (PVT), a dislocation blocking buffer layer (DBBL) has been simply developed by optimizing the AlN growth parameters such as temperature gradient (ΔT), substrate temperature (Tsub), and N2 partial pressure (PN2) at the initial growth stage. Increase in ΔT resulted in the formation of an abrupt AlN/SiC interface due to the suppression of inhomogeneous thermal decomposition at the interface and the subsequent AlN unstable island growth. The well-defined AlN/SiC interface played an important role in controlling the two kinds of different AlN growth mode in-situ as functions of Tsub and PN2. One is a continuous step-flow growth mode, and the other is a discontinuous platelet-like growth. The discontinuous AlN layer, consisting of thin AlN platelets and air-gaps inserted between the two adjacent platelets, acted as the DBBL. By introducing the DBBL at the initial growth stage, followed by the step-flow growth, continuous AlN layer with dislocation density of 1.7 × 106 cm-2 was achieved at a total growth thickness of 60 μm, which is two orders of magnitude lower than the previously reported value.

  14. Thermal diffusivity of ferrofluids as a function of particle size determined using the mode-mismatched dual-beam thermal lens technique

    Science.gov (United States)

    Lenart, V. M.; Astrath, N. G. C.; Turchiello, R. F.; Goya, G. F.; Gómez, S. L.

    2018-02-01

    Ferrofluids are colloids of superparamagnetic nanoparticles that are envisaged for use in hyperthermia, which is based on nonradiative relaxation after interaction with a high-frequency magnetic field or light. For such applications, an important parameter is the thermal diffusivity. In this communication, we present an experimental study of the dependence of thermal diffusivity of ferrofluids on the size of the magnetite nanoparticles by employing the mode-mismatched thermal lens technique. The results show a huge enhancement of the thermal diffusivity by increasing the average size of the nanoparticles, while the number density of the nanoparticles is maintained as constant.

  15. Application of small-signal modeling and measurement techniques to the stability analysis of an integrated switching-mode power system. [onboard Dynamics Explorer Satellite

    Science.gov (United States)

    Wong, R. C.; Owen, H. A., Jr.; Wilson, T. G.; Rodriguez, G. E.

    1980-01-01

    Small-signal modeling techniques are used in a system stability analysis of a breadboard version of a complete functional electrical power system. The system consists of a regulated switching dc-to-dc converter, a solar-cell-array simulator, a solar-array EMI filter, battery chargers and linear shunt regulators. Loss mechanisms in the converter power stage, including switching-time effects in the semiconductor elements, are incorporated into the modeling procedure to provide an accurate representation of the system without requiring frequency-domain measurements to determine the damping factor. The small-signal system model is validated by the use of special measurement techniques which are adapted to the poor signal-to-noise ratio encountered in switching-mode systems. The complete electrical power system with the solar-array EMI filter is shown to be stable over the intended range of operation.

  16. Characterization technique for long optical fiber cavities based on beating spectrum of multi-longitudinal mode fiber laser and beating spectrum in the RF domain

    Science.gov (United States)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2016-03-01

    The characterization of long fiber cavities is essential for many systems to predict the system practical performance. The conventional techniques for optical cavity characterization are not suitable for long fiber cavities due to the cavities' small free spectral ranges and due to the length variations caused by the environmental effects. In this work, we present a novel technique to characterize long fiber cavities using multi-longitudinal mode fiber laser source and RF spectrum analyzer. The fiber laser source is formed in a ring configuration, where the fiber laser cavity length is chosen to be 15 km to ensure that the free spectral range is much smaller than the free spectral range of the characterized passive fiber cavities. The method has been applied experimentally to characterize ring cavities with lengths of 6.2 m and 2.4 km. The results are compared to theoretical predictions with very good agreement.

  17. Comparative study of radiation dose and image noise between single-source fast kilo voltage peak switching technique and conventional mode on abdominal CT

    International Nuclear Information System (INIS)

    Lin Xiaozhu; Xu Xueqin; Chen Kemin; Yan Fuhua; Isao Tanaka; Rika Fukui; Haruhiko Machida; Eiko Ueno

    2013-01-01

    Objective: To investigate the radiation dose and image noise of abdominal CT with spectral imaging and conventional scan mode. Methods: This was a retrospective study. The first part of this study was a phantom study. A standard quality assessment phantom was scanned with gemstone spectral imaging mode and conventional helical mode using 120 kVp with different mAs. A regression function for the mAs between conventional scan mode and spectral imaging mode was obtained. According to the regression function, the mAs on 120 kVp corresponding to different gemstone spectral imaging protocol were calculated. The second part of this study was a clinical study. Twenty-two patients who underwent contrast enhanced abdominal CT scanning were included. The pre-contrast CT was scanned by a conventional mode with automatic exposure control technique. According to the mAs of pre-contrast scan, corresponding spectral imaging parameters were selected for the portal venous phase of post-contrast scan. Five sets of images with 5 mm slice thickness were reconstructed, with 65 keV monochromatic image for spectral imaging and FBP, 20%,40% and 60% ASIR image for conventional imaging respectively. Image noise was measured on hepatic parenchyma and urinary bladder for each set of image. Radiation dose and image noise were compared between CT spectral imaging and conventional imaging with paired t-test. Results: No significant differences were found for the CTDIvol [(13.8 ± 4.8) mGy versus (14.0 ± 7.0) mGy] and DLP [(691.1 ± 274.2) mGy · cm versus (678.8 ± 385.0) mGy · cm] between CT spectral imaging and conventional imaging. Monochromatic image (65 keV) by spectral imaging [(7.6 ± 1.4) HU for hepatic parenchyma and (9.1 ± 1.3) HU for urinary bladder] had equal image noise with 40% ASIR [hepatic parenchyma: (7.8 ±0.7) HU] and 20% ASIR [urinary bladder: (9.2 ± 1.2) HU] and lower image noise than FBP image [(10.4 ± 1.0) HU for hepatic parenchyma and (10.5 ± 1.3) HU for urinary

  18. On the generalization of constraint programming and boolean satisfiability solving techniques to schedule a resource-constrained project consisting of multi-mode jobs

    Directory of Open Access Journals (Sweden)

    Alexander Schnell

    Full Text Available In our paper, we analyze new exact approaches for the multi-mode resource-constrained project scheduling (MRCPSP problem with the aim of makespan minimization. For the single-mode RCPSP (SRCPSP recent exact algorithms combine a Branch and Bound algorithm with principles from Constraint Programming (CP and Boolean Satisfiability Solving (SAT. We extend the above principles for the solution of MRCPSP instances. This generalization is on the one hand achieved on the modeling level. We propose three CP-based formulations of the MRCPSP for the G12 CP platform and the optimization framework SCIP which both provide solution techniques combining CP and SAT principles. For one of the latter we implemented a new global constraint for SCIP, which generalizes the domain propagation and explanation generation principles for renewable resources in the context of multi-mode jobs. Our constraint applies the above principles in a more general way than the existing global constraint in SCIP. We compare our approaches with the state-of-the-art exact algorithm from the literature on MRCPSP instances with 20 and 30 jobs. Our computational experiments show that we can outperform the latter approach on these instances. Furthermore, we are the first to close (find the optimal solution and prove its optimality for 628 open instances with 50 and 100 jobs from the literature. In addition, we improve the best known lower bound of 2815 instances and the best known upper bound of 151 instances. Keywords: Multi-mode resource-constrained project scheduling, Constraint programming, SAT solving, SCIP, Lazy clause generation, Exact algorithm

  19. Sliding mode controller gain adaptation and chattering reduction techniques for DSP-based PM DC motor drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus

    2011-01-01

    simulations. To demonstrate the effectiveness of each method, several experiments were performed on a DSP-based PM DC motor drive system. Then, the newly proposed combinations of these methods were implemented. The hardware implementation results are comparatively presented and discussed....... reduction techniques are investigated, and the effectiveness of chattering suppression for current regulation of PM DC drives is tested. The sampling rate was also examined to determine how it affects the amplitude of chattering. This paper concentrates on various combinations of observer-based methods...

  20. S1-ZGV Modes of a Linear and Nonlinear Profile for Functionally Graded Material Using Power Series Technique

    Directory of Open Access Journals (Sweden)

    M. Zagrouba

    2014-01-01

    Full Text Available The present work deals with functionally graded materials (FGM isotropic plates in the neighborhood of the first-order symmetric zero group velocity (S1-ZGV point. The mechanical properties of functionally graded material (FGM are assumed to vary continuously through the thickness of the plate and obey a power law of the volume fraction of the constituents. Governing equations for the problem are derived, and the power series technique (PST is employed to solve the recursive equations. The impact of the FGM basic materials properties on S1-ZGV frequency of FGM plate is investigated. Numerical results show that S1-ZGV frequency is comparatively more sensitive to the shear modulus. The gradient coefficient p does not affect the linear dependence of ZGV frequency fo as function of cut-off frequency fc; only the slope is slightly varied.

  1. A Phase Matching, Adiabatic Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Lemery, Francois [Hamburg U.; Flöttmann, Klaus [DESY; Kärtner, Franz [CFEL, Hamburg; Piot, Philippe [Northern Illinois U.

    2017-05-01

    Tabletop accelerators are a thing of the future. Reducing their size will require scaling down electromagnetic wavelengths; however, without correspondingly high field gradients, particles will be more susceptible to phase-slippage – especially at low energy. We investigate how an adiabatically-tapered dielectric-lined waveguide could maintain phase-matching between the accelerating mode and electron bunch. We benchmark our simple model with CST and implement it into ASTRA; finally we provide a first glimpse into the beam dynamics in a phase-matching accelerator.

  2. 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...

  3. Image Matching Using Generalized Hough Transforms

    Science.gov (United States)

    Davis, L. S.; Hu, F. P.; Hwang, V.; Kitchen, L.

    1983-01-01

    An image matching system specifically designed to match dissimilar images is described. A set of blobs and ribbons is first extracted from each image, and then generalized Hough transform techniques are used to match these sets and compute the transformation that best registers the image. An example of the application of the approach to one pair of remotely sensed images is presented.

  4. Sample evaluation of ontology-matching systems

    NARCIS (Netherlands)

    Hage, W.R. van; Isaac, A.; Aleksovski, Z.

    2007-01-01

    Ontology matching exists to solve practical problems. Hence, methodologies to find and evaluate solutions for ontology matching should be centered on practical problems. In this paper we propose two statistically-founded evaluation techniques to assess ontology-matching performance that are based on

  5. Multi-Mode Elastic Peak Electron Microscopy (MM-EPEM): A new imaging technique with an ultimate in-depth resolution for surface analysis.

    Science.gov (United States)

    Aymen Mahjoub, Mohamed; Monier, Guillaume; Bideux, Luc; Gruzza, Bernard; Robert-Goumet, Christine

    2018-05-01

    A non-destructive new imaging technique called Multi-Mode Elastic Peak Electron Microscopy (MM-EPEM), hypersensitive to surface chemistry and with an in-depth resolution of one atomic monolayer was developed. This method consists on performing several MM-EPEM images containing n × n pixels associated to an intensity of the elastic backscattered electrons by varying the incident electron energy in the range 200-2000 eV. This approach allows obtaining depth sampling information of the analyzed structures. Furthermore, MM-EPEM is associated with Monte-Carlo simulations describing the electron pathway in materials in order to obtain very precise quantitative information, for instance the growth mode and the organization of ultra-thin layers (2D materials) or nanoparticules. In this work, we used this new method to study the deposition of very small amount of gold down to one monolayer. Example of 3D reconstruction is also provided. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. The Galaxies Hubble Sequence Through CosmicTimes: Applying Parameter Optimization And Constraints From The Abundance Matching Technique To The 'Next Generation' of Large Cosmological Simulations.

    Science.gov (United States)

    Governato, Fabio

    The physical processes shaping the galaxies 'Hubble Sequence' are still poorly understood. Are gas outflows generated by Supernovae the main mechanism responsible for regulating star formation and the establishing the stellar mass - metallicity relation? What fraction of stars now in spheroids was originated in mergers? How does the environment of groups and clusters affect the evolution of galaxy satellites? The PI will study these problems analyzing a new set of state of the art hydro simulations of uniform cosmological volumes. This project has already been awarded a computational budget of 200 million CPU hours (but has only limited seed funding for science, hence this proposal). The best simulations will match the force and spatial resolution of the current best 'zoomed in' runs, as 'Eris' and will yield the first large statistical sample (1500+) of internally resolved galaxy systems with stellar masses ranging from from 10^7 to 10^10.5 solar masses. These simulations will allow us, for the very first time on such a large statistical set, to fully map the thermodynamical history of the baryons of internally resolved galaxies and identify the relative importance of the processes that shape their evolution as a function of stellar mass and cosmic time. As a novel, significant improvement over previous works we will introduce a new, unbiased statistical approach to the exploration of parameter space to optimize the model for star formation (SF) and feedback from supernovae and super massive back holes. This approach will also be used to evaluate the effects of resolution. The simulations will be run using ChaNGa, an improved version of Gasoline. Our flagship run will model a large volume of space (15.6k cubic Mpc) using 25 billion resolution elements. ChaNGa currently scales up to 35,000 cores and include a new version of the SPH implementation that drastically improves the description of temperature/density discontinuities and Kelvin-Helmholtz instabilities (and

  7. Lichtenstein Versus Total Extraperitoneal Patch Plasty Versus Transabdominal Patch Plasty Technique for Primary Unilateral Inguinal Hernia Repair: A Registry-based, Propensity Score-matched Comparison of 57,906 Patients.

    Science.gov (United States)

    Köckerling, Ferdinand; Bittner, Reinhard; Kofler, Michael; Mayer, Franz; Adolf, Daniela; Kuthe, Andreas; Weyhe, Dirk

    2017-09-26

    Outcome comparison of the Lichtenstein, total extraperitoneal patch plasty (TEP), and transabdominal patch plasty (TAPP) techniques for primary unilateral inguinal hernia repair. For comparison of these techniques the number of cases included in meta-analyses of randomized controlled trials is limited. There is therefore an urgent need for more comparative data. In total, 57,906 patients with a primary unilateral inguinal hernia and 1-year follow up from the Herniamed Registry were selected between September 1, 2009 and February 1, 2015. Using propensity score matching, 12,564 matched pairs were formed for comparison of Lichtenstein versus TEP, 16,375 for Lichtenstein versus TAPP, and 14,426 for TEP versus TAPP. Comparison of Lichtenstein versus TEP revealed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.4% vs 1.7%; P comparison of Lichtenstein versus TAPP showed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.8% vs 3.3%; P = 0.029), complication-related reoperations (1.2% vs 0.9%; P = 0.019), pain at rest (5% vs 4.5%; P = 0.029), and on exertion (10.2% vs 7.8%; P < 0.001). TEP and TAPP were found to have advantages over the Lichtenstein operation.

  8. Toward Practical Secure Stable Matching

    Directory of Open Access Journals (Sweden)

    Riazi M. Sadegh

    2017-01-01

    Full Text Available The Stable Matching (SM algorithm has been deployed in many real-world scenarios including the National Residency Matching Program (NRMP and financial applications such as matching of suppliers and consumers in capital markets. Since these applications typically involve highly sensitive information such as the underlying preference lists, their current implementations rely on trusted third parties. This paper introduces the first provably secure and scalable implementation of SM based on Yao’s garbled circuit protocol and Oblivious RAM (ORAM. Our scheme can securely compute a stable match for 8k pairs four orders of magnitude faster than the previously best known method. We achieve this by introducing a compact and efficient sub-linear size circuit. We even further decrease the computation cost by three orders of magnitude by proposing a novel technique to avoid unnecessary iterations in the SM algorithm. We evaluate our implementation for several problem sizes and plan to publish it as open-source.

  9. Single-incision laparoscopic surgery using colon-lifting technique for colorectal cancer: a matched case-control comparison with standard multiport laparoscopic surgery in terms of short-term results and access instrument cost.

    Science.gov (United States)

    Fujii, Shoichi; Watanabe, Kazuteru; Ota, Mitsuyoshi; Watanabe, Jun; Ichikawa, Yasushi; Yamagishi, Shigeru; Tatsumi, Kenji; Suwa, Hirokazu; Kunisaki, Chikara; Taguri, Masataka; Morita, Satoshi; Endo, Itaru

    2012-05-01

    Single-incision laparoscopic surgery (SILS) has been used for colorectal cancer as a minimally invasive procedure. However, there are still difficulties concerning effective triangulation and countertraction. The study's purpose was to clarify the usefulness of the colon-lifting technique (CLT) in SILS for colorectal cancer. SILS was performed for cancer (cT2N0 or less) of the right-sided colon (near the ileocecum), sigmoid, or rectosigmoid. The SILS™ Port was used for transumbilical access. A suture string was inserted through the abdominal wall and passed through the mesocolon. The colon was retracted anteriorly and fixed to the abdominal wall. The main mesenteric vessels were placed under tension. Lymph node dissection was performed by medial approach. Short-term surgical outcomes and access port costs were compared between SILS (using CLT) and the standard multiport technique (MPT). The two groups were case-matched by propensity scoring. Analyzed variables included preoperative Dukes stage and tumor location. From June 2009 to April 2011, 27 patients underwent SILS, and from April 2005 to April 2011, 85 patients underwent MPT. Propensity scoring generated 23 matched patients per group for SILS versus MPT comparisons. There were no significant differences in operating time, blood loss, early complications, postoperative analgesic frequency, or length of hospital stay. One MPT patient was converted to open surgery (4.5%); no SILS patients were converted. There were no significant differences in the length of distal cut margin and the number of harvested lymph nodes, except incision length (SILS vs. MPT: 33 vs. 55 mm, P Japanese yen, P CLT was safe and effective in providing radical treatment of cT2N0 cancer in the right-sided colon, sigmoid, or rectosigmoid. SILS was advantageous with respect to cosmesis and lower cost of access instruments.

  10. Which Combinations of Techniques and Modes of Delivery in Internet-Based Interventions Effectively Change Health Behavior? A Meta-Analysis.

    Science.gov (United States)

    van Genugten, Lenneke; Dusseldorp, Elise; Webb, Thomas Llewelyn; van Empelen, Pepijn

    2016-06-07

    Many online interventions designed to promote health behaviors combine multiple behavior change techniques (BCTs), adopt different modes of delivery (MoD) (eg, text messages), and range in how usable they are. Research is therefore needed to examine the impact of these features on the effectiveness of online interventions. This study applies Classification and Regression Trees (CART) analysis to meta-analytic data, in order to identify synergistic effects of BCTs, MoDs, and usability factors. We analyzed data from Webb et al. This review included effect sizes from 52 online interventions targeting a variety of health behaviors and coded the use of 40 BCTs and 11 MoDs. Our research also developed a taxonomy for coding the usability of interventions. Meta-CART analyses were performed using the BCTs and MoDs as predictors and using treatment success (ie, effect size) as the outcome. Factors related to usability of the interventions influenced their efficacy. Specifically, subgroup analyses indicated that more efficient interventions (interventions that take little time to understand and use) are more likely to be effective than less efficient interventions. Meta-CART identified one synergistic effect: Interventions that included barrier identification/ problem solving and provided rewards for behavior change reported an average effect size that was smaller (ḡ=0.23, 95% CI 0.08-0.44) than interventions that used other combinations of techniques (ḡ=0.43, 95% CI 0.27-0.59). No synergistic effects were found for MoDs or for MoDs combined with BCTs. Interventions that take little time to understand and use were more effective than those that require more time. Few specific combinations of BCTs that contribute to the effectiveness of online interventions were found. Furthermore, no synergistic effects between BCTs and MoDs were found, even though MoDs had strong effects when analyzed univariately in the original study.

  11. The Use of MTM-SVD Technique to Explore the Joint Spatiotemporal Modes of Wind and Sea Surface Variability in the North Indian Ocean during 1993–2005

    Directory of Open Access Journals (Sweden)

    Thaned Rojsiraphisal

    2009-01-01

    Full Text Available Sea surface height (SSH and sea surface temperature (SST in the North Indian Ocean are affected predominantly by the seasonally reversing monsoons and in turn feed back on monsoon variability. In this study, a set of data generated from a data-assimilative ocean model is used to examine coherent spatiotemporal modes of variability of winds and surface parameters using a frequency domain technique, Multiple Taper Method with Singular Value Decomposition (MTM-SVD. The analysis shows significant variability at annual and semiannual frequencies in these fields individually and jointly. The joint variability of winds and SSH is significant at interannual (2-3 years timescale related to the ENSO mode—with a “/dipole/” like spatial pattern. Joint variability with SST showed similar but somewhat weaker behavior. Winds appear to be the driver of variability in both SSH and SST at these frequency bands. This offers prospects for long-lead projections of the North Indian Ocean climate.

  12. Pixel Decimation in Block Matching Techniques

    Directory of Open Access Journals (Sweden)

    D. Levicky

    2000-12-01

    Full Text Available Block motion estimation using full search algorithm is computationallyextensive. Previously proposed fast algorithms reduce the computationcost by limiting the number of locations searched. In this paper wepresent algorithms for block motion estimation that produce similarperformance to that full search algorithm. The algorithms are based onthe pixel decimation.

  13. Stinging Insect Matching Game

    Science.gov (United States)

    ... for Kids ▸ Stinging Insect Matching Game Share | Stinging Insect Matching Game Stinging insects can ruin summer fun for those who are ... the difference between the different kinds of stinging insects in order to keep your summer safe and ...

  14. Matching Systems for Refugees

    Directory of Open Access Journals (Sweden)

    Will Jones

    2017-08-01

    Full Text Available Design of matching systems between refugees and states or local areas is emerging as one of the most promising solutions to problems in refugee resettlement. We describe the basics of two-sided matching theory used in a number of allocation problems, such as school choice, where both sides need to agree to the match. We then explain how these insights can be applied to international refugee matching in the context of the European Union and examine how refugee matching might work within the United Kingdom, Canada, and the United States.

  15. Matching Students to Schools

    Directory of Open Access Journals (Sweden)

    Dejan Trifunovic

    2017-08-01

    Full Text Available In this paper, we present the problem of matching students to schools by using different matching mechanisms. This market is specific since public schools are free and the price mechanism cannot be used to determine the optimal allocation of children in schools. Therefore, it is necessary to use different matching algorithms that mimic the market mechanism and enable us to determine the core of the cooperative game. In this paper, we will determine that it is possible to apply cooperative game theory in matching problems. This review paper is based on illustrative examples aiming to compare matching algorithms in terms of the incentive compatibility, stability and efficiency of the matching. In this paper we will present some specific problems that may occur in matching, such as improving the quality of schools, favoring minority students, the limited length of the list of preferences and generating strict priorities from weak priorities.

  16. Best matching theory & applications

    CERN Document Server

    Moghaddam, Mohsen

    2017-01-01

    Mismatch or best match? This book demonstrates that best matching of individual entities to each other is essential to ensure smooth conduct and successful competitiveness in any distributed system, natural and artificial. Interactions must be optimized through best matching in planning and scheduling, enterprise network design, transportation and construction planning, recruitment, problem solving, selective assembly, team formation, sensor network design, and more. Fundamentals of best matching in distributed and collaborative systems are explained by providing: § Methodical analysis of various multidimensional best matching processes § Comprehensive taxonomy, comparing different best matching problems and processes § Systematic identification of systems’ hierarchy, nature of interactions, and distribution of decision-making and control functions § Practical formulation of solutions based on a library of best matching algorithms and protocols, ready for direct applications and apps development. Design...

  17. Nonlinear soliton matching between optical fibers

    DEFF Research Database (Denmark)

    Agger, Christian; Sørensen, Simon Toft; Thomsen, Carsten L.

    2011-01-01

    In this Letter, we propose a generic nonlinear coupling coefficient, η2 NL ¼ ηjγ=β2jfiber2=jγ=β2jfiber1, which gives a quantitative measure for the efficiency of nonlinear matching of optical fibers by describing how a fundamental soliton couples from one fiber into another. Specifically, we use η......NL to demonstrate a significant soliton selffrequency shift of a fundamental soliton, and we show that nonlinear matching can take precedence over linear mode matching. The nonlinear coupling coefficient depends on both the dispersion (β2) and nonlinearity (γ), as well as on the power coupling efficiency η. Being...

  18. Sliding mode control and observation

    CERN Document Server

    Shtessel, Yuri; Fridman, Leonid; Levant, Arie

    2014-01-01

    The sliding mode control methodology has proven effective in dealing with complex dynamical systems affected by disturbances, uncertainties and unmodeled dynamics. Robust control technology based on this methodology has been applied to many real-world problems, especially in the areas of aerospace control, electric power systems, electromechanical systems, and robotics. Sliding Mode Control and Observation represents the first textbook that starts with classical sliding mode control techniques and progresses toward newly developed higher-order sliding mode control and observation algorithms and their applications. The present volume addresses a range of sliding mode control issues, including: *Conventional sliding mode controller and observer design *Second-order sliding mode controllers and differentiators *Frequency domain analysis of conventional and second-order sliding mode controllers *Higher-order sliding mode controllers and differentiators *Higher-order sliding mode observers *Sliding mode disturbanc...

  19. Dynamic Caliper Matching

    OpenAIRE

    Paweł Strawiński

    2011-01-01

    Matched sampling is a methodology used to estimate treatment effects. A caliper mechanism is used to achieve better similarity among matched pairs. We investigate finite sample properties of matching with calipers and propose a slight modification to the existing mechanism. The simulation study compares the performance of both methods and shows that a standard caliper performs well only in case of constant treatment or uniform propensity score distribution. Secondly, in a case of non-uniform ...

  20. Impedance-matched drilling telemetry system

    Science.gov (United States)

    Normann, Randy A [Edgewood, NM; Mansure, Arthur J [Albuquerque, NM

    2008-04-22

    A downhole telemetry system that uses inductance or capacitance as a mode through which signal is communicated across joints between assembled lengths of pipe wherein efficiency of signal propagation through a drill string, for example, over multiple successive pipe segments is enhanced through matching impedances associated with the various telemetry system components.

  1. Anomalous dispersion enhanced Cerenkov phase-matching

    Energy Technology Data Exchange (ETDEWEB)

    Kowalczyk, T.C.; Singer, K.D. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Physics; Cahill, P.A. [Sandia National Labs., Albuquerque, NM (United States)

    1993-11-01

    The authors report on a scheme for phase-matching second harmonic generation in polymer waveguides based on the use of anomalous dispersion to optimize Cerenkov phase matching. They have used the theoretical results of Hashizume et al. and Onda and Ito to design an optimum structure for phase-matched conversion. They have found that the use of anomalous dispersion in the design results in a 100-fold enhancement in the calculated conversion efficiency. This technique also overcomes the limitation of anomalous dispersion phase-matching which results from absorption at the second harmonic. Experiments are in progress to demonstrate these results.

  2. Semantic Data Matching: Principles and Performance

    Science.gov (United States)

    Deaton, Russell; Doan, Thao; Schweiger, Tom

    Automated and real-time management of customer relationships requires robust and intelligent data matching across widespread and diverse data sources. Simple string matching algorithms, such as dynamic programming, can handle typographical errors in the data, but are less able to match records that require contextual and experiential knowledge. Latent Semantic Indexing (LSI) (Berry et al. ; Deerwester et al. is a machine intelligence technique that can match data based upon higher order structure, and is able to handle difficult problems, such as words that have different meanings but the same spelling, are synonymous, or have multiple meanings. Essentially, the technique matches records based upon context, or mathematically quantifying when terms occur in the same record.

  3. An Inter-Comparison of Techniques for Determining Velocities of Maritime Arctic Glaciers, Svalbard, Using Radarsat-2 Wide Fine Mode Data

    Directory of Open Access Journals (Sweden)

    Thomas Schellenberger

    2016-09-01

    Full Text Available Glacier dynamics play an important role in the mass balance of many glaciers, ice caps and ice sheets. In this study we exploit Radarsat-2 (RS-2 Wide Fine (WF data to determine the surface speed of Svalbard glaciers in the winters of 2012/2013 and 2013/2014 using Synthetic Aperture RADAR (SAR offset and speckle tracking. The RS-2 WF mode combines the advantages of the large spatial coverage of the Wide mode (150 × 150 km and the high pixel resolution (9 m of the Fine mode and thus has a major potential for glacier velocity monitoring from space through offset and speckle tracking. Faster flowing glaciers (1.95 m·d−1–2.55 m·d−1 that are studied in detail are Nathorstbreen, Kronebreen, Kongsbreen and Monacobreen. Using our Radarsat-2 WF dataset, we compare the performance of two SAR tracking algorithms, namely the GAMMA Remote Sensing Software and a custom written MATLAB script (GRAY method that has primarily been used in the Canadian Arctic. Both algorithms provide comparable results, especially for the faster flowing glaciers and the termini of slower tidewater glaciers. A comparison of the WF data to RS-2 Ultrafine and Wide mode data reveals the superiority of RS-2 WF data over the Wide mode data.

  4. Ontology Matching Across Domains

    Science.gov (United States)

    2010-05-01

    matching include GMO [1], Anchor-Prompt [2], and Similarity Flooding [3]. GMO is an iterative structural matcher, which uses RDF bipartite graphs to...AFRL under contract# FA8750-09-C-0058. References [1] Hu, W., Jian, N., Qu, Y., Wang, Y., “ GMO : a graph matching for ontologies”, in: Proceedings of

  5. Matched-pair classification

    Energy Technology Data Exchange (ETDEWEB)

    Theiler, James P [Los Alamos National Laboratory

    2009-01-01

    Following an analogous distinction in statistical hypothesis testing, we investigate variants of machine learning where the training set comes in matched pairs. We demonstrate that even conventional classifiers can exhibit improved performance when the input data has a matched-pair structure. Online algorithms, in particular, converge quicker when the data is presented in pairs. In some scenarios (such as the weak signal detection problem), matched pairs can be generated from independent samples, with the effect not only doubling the nominal size of the training set, but of providing the structure that leads to better learning. A family of 'dipole' algorithms is introduced that explicitly takes advantage of matched-pair structure in the input data and leads to further performance gains. Finally, we illustrate the application of matched-pair learning to chemical plume detection in hyperspectral imagery.

  6. Towards optimal packed string matching

    DEFF Research Database (Denmark)

    Ben-Kiki, Oren; Bille, Philip; Breslauer, Dany

    2014-01-01

    In the packed string matching problem, it is assumed that each machine word can accommodate up to α characters, thus an n-character string occupies n/α memory words.(a) We extend the Crochemore–Perrin constant-space O(n)-time string-matching algorithm to run in optimal O(n/α) time and even in real......-time, achieving a factor α speedup over traditional algorithms that examine each character individually. Our macro-level algorithm only uses the standard AC0 instructions of the word-RAM model (i.e. no integer multiplication) plus two specialized micro-level AC0 word-size packed-string instructions. The main word...... matching work.(b) We also consider the complexity of the packed string matching problem in the classical word-RAM model in the absence of the specialized micro-level instructions wssm and wslm. We propose micro-level algorithms for the theoretically efficient emulation using parallel algorithms techniques...

  7. Latent fingerprint matching.

    Science.gov (United States)

    Jain, Anil K; Feng, Jianjiang

    2011-01-01

    Latent fingerprint identification is of critical importance to law enforcement agencies in identifying suspects: Latent fingerprints are inadvertent impressions left by fingers on surfaces of objects. While tremendous progress has been made in plain and rolled fingerprint matching, latent fingerprint matching continues to be a difficult problem. Poor quality of ridge impressions, small finger area, and large nonlinear distortion are the main difficulties in latent fingerprint matching compared to plain or rolled fingerprint matching. We propose a system for matching latent fingerprints found at crime scenes to rolled fingerprints enrolled in law enforcement databases. In addition to minutiae, we also use extended features, including singularity, ridge quality map, ridge flow map, ridge wavelength map, and skeleton. We tested our system by matching 258 latents in the NIST SD27 database against a background database of 29,257 rolled fingerprints obtained by combining the NIST SD4, SD14, and SD27 databases. The minutiae-based baseline rank-1 identification rate of 34.9 percent was improved to 74 percent when extended features were used. In order to evaluate the relative importance of each extended feature, these features were incrementally used in the order of their cost in marking by latent experts. The experimental results indicate that singularity, ridge quality map, and ridge flow map are the most effective features in improving the matching accuracy.

  8. Monte Carlo search techniques applied to the measurement of higher mode phase velocities and anisotropic surface wave tomography. Geologica Ultraiectina (285)

    NARCIS (Netherlands)

    Visser, K.

    2008-01-01

    In this thesis we present all three stages of the inversion approach proposed by Kennett and Yoshizawa (2002). The three stage inversion approach consists of obtaining fundamental and higher mode Love and Rayleigh wave phase velocity measurements through waveform fitting in the first stage,

  9. Optimal Packed String Matching

    DEFF Research Database (Denmark)

    Ben-Kiki, Oren; Bille, Philip; Breslauer, Dany

    2011-01-01

    In the packed string matching problem, each machine word accommodates – characters, thus an n-character text occupies n/– memory words. We extend the Crochemore-Perrin constantspace O(n)-time string matching algorithm to run in optimal O(n/–) time and even in real-time, achieving a factor – speedup...... over traditional algorithms that examine each character individually. Our solution can be efficiently implemented, unlike prior theoretical packed string matching work. We adapt the standard RAM model and only use its AC0 instructions (i.e., no multiplication) plus two specialized AC0 packed string...

  10. Face recognition using ensemble string matching.

    Science.gov (United States)

    Chen, Weiping; Gao, Yongsheng

    2013-12-01

    In this paper, we present a syntactic string matching approach to solve the frontal face recognition problem. String matching is a powerful partial matching technique, but is not suitable for frontal face recognition due to its requirement of globally sequential representation and the complex nature of human faces, containing discontinuous and non-sequential features. Here, we build a compact syntactic Stringface representation, which is an ensemble of strings. A novel ensemble string matching approach that can perform non-sequential string matching between two Stringfaces is proposed. It is invariant to the sequential order of strings and the direction of each string. The embedded partial matching mechanism enables our method to automatically use every piece of non-occluded region, regardless of shape, in the recognition process. The encouraging results demonstrate the feasibility and effectiveness of using syntactic methods for face recognition from a single exemplar image per person, breaking the barrier that prevents string matching techniques from being used for addressing complex image recognition problems. The proposed method not only achieved significantly better performance in recognizing partially occluded faces, but also showed its ability to perform direct matching between sketch faces and photo faces.

  11. Higher Order Mode Fibers

    DEFF Research Database (Denmark)

    Israelsen, Stine Møller

    . In the second part of the thesis, a new scheme for constructing chirped microbend long period gratings is presented. The method presents a versatile platform for tailoring the chirp to the phase matching profile of the targeted HOM conversion in the fiber under test. The scheme introduces the ability......This PhD thesis considers higher order modes (HOMs) in optical fibers. That includes their excitation and characteristics. Within the last decades, HOMs have been applied both for space multiplexing in optical communications, group velocity dispersion management and sensing among others......-radial polarization as opposed to the linear polarization of the LP0X modes. The effect is investigated numerically in a double cladding fiber with an outer aircladding using a full vectorial modesolver. Experimentally, the bowtie modes are excited using a long period grating and their free space characteristics...

  12. Pediatric MATCH Infographic

    Science.gov (United States)

    Infographic explaining NCI-COG Pediatric MATCH, a cancer treatment clinical trial for children and adolescents, from 1 to 21 years of age, that is testing the use of precision medicine for pediatric cancers.

  13. RETIRED MATCHES AMONG MALE PROFESSIONAL TENNIS PLAYERS

    Directory of Open Access Journals (Sweden)

    Kristijan Breznik

    2012-06-01

    Full Text Available The aim of this study was to explore the effect of characteristics of various games and players on the proportion of retired tennis matches in the Open Era of tennis. The data included over 420,000 matches played among 17,553 tennis players in the period from 1968 to the end of 2010. The influence of the surface type was clearly confirmed, with the proportion of retired matches being higher on hard and clay courts compared to grass and carpet surfaces. Similarly, more retired matches were observed in outdoor venues than in indoor ones. The impact of other variables, tournament types, rounds at which the game was played and both players' ranks, is more ambiguous. Our interpretation of the obtained results is presented in the paper. Network analytic methods were applied to extract players with the most retired matches in their careers. Eventually, we defined a group of top tennis players and gave a more precise insight into retired matches in that group. Correspondence analysis was used to visually display the two-mode network of top players and the proportion of retired matches by surface type

  14. Matching conditions on capillary ripples

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Aresky H.; Marin Antuna, J.; Rodriguez Coppola, H. [Universidad de La Habana, La Habana (Cuba)

    2001-12-01

    The physics of the oscillatory motion in the interface between two immiscible viscous fluids is presented based on a detailed analysis of the matching conditions. These conditions are almost completely derived from the dynamical equations of the system. This unusual approach in graduated courses in hydrodynamics, is proposed as an alternative. The role of viscosity in the modes of oscillation of the interface is also clearly shown. [Spanish] Se explica la fisica de las oscilaciones de la interfase de dos fluidos viscosos no miscibles a partir del analisis detallado de las condiciones de empalme que se derivan casi completamente del sistema de ecuaciones dinamicas que lo rigen. Ese enfoque, no habitual en los cursos de doctorado de esta materia, se propone como alternativa para estos cursos. Se explica tambien de forma clara el posible papel de la viscosidad en los modos de oscilacion de la interfase.

  15. Matching Speaking to Singing Voices and the Influence of Content.

    Science.gov (United States)

    Peynircioğlu, Zehra F; Rabinovitz, Brian E; Repice, Juliana

    2017-03-01

    We tested whether speaking voices of unfamiliar people could be matched to their singing voices, and, if so, whether the content of the utterances would influence this matching performance. Our hypothesis was that enough acoustic features would remain the same between speaking and singing voices such that their identification as belonging to the same or different individuals would be possible even upon a single hearing. We also hypothesized that the contents of the utterances would influence this identification process such that voices uttering words would be easier to match than those uttering vowels. We used a within-participant design with blocked stimuli that were counterbalanced using a Latin square design. In one block, mode (speaking vs singing) was manipulated while content was held constant; in another block, content (word vs syllable) was manipulated while mode was held constant, and in the control block, both mode and content were held constant. Participants indicated whether the voices in any given pair of utterances belonged to the same person or to different people. Cross-mode matching was above chance level, although mode-congruent performance was better. Further, only speaking voices were easier to match when uttering words. We can identify speaking and singing voices as the same or different even on just a single hearing. However, content interacts with mode such that words benefit matching of speaking voices but not of singing voices. Results are discussed within an attentional framework. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  16. Halo control, beam matching, and new dynamical variables for beam distributions

    International Nuclear Information System (INIS)

    Lysenko, W.; Parsa, Z.

    1997-01-01

    We present the status of our work on physics models that relate release to the understanding and control of beam halo, which is a cause of particle loss in high power ion linear accelerators. We can minimize these particle losses, even in the presence of nonlinearities, by ensuring the beam is matched to high order. Our goal is to determine new dynamical variables that enable us to more directly solve for the evolution of the halo. We considered moments and several new variables, using a Lie-Poisson formulation whenever possible. Using symbolic techniques, we computed high-order matches and mode invariants (analogs of moment invariants) in the new variables. A promising new development developments is that of the variables we call weighted moments, which allow us to compute high-order nonlinear effects (like halos) while making use of well-developed existing results and computational techniques developed for studying first order effects. copyright 1997 American Institute of Physics

  17. Matching Parasitic Antenna for Single RF MIMO

    DEFF Research Database (Denmark)

    Han, Bo; Kalis, A; Nielsen, Rasmus Hjorth

    2012-01-01

    . In order to have such performance, an antenna with rich pattern modes is required by the system, thus the ESPAR antenna is investigated. The critical part on such antenna is parasitic element impedance matching. Unlike the conventional smith-chart matching method which assumes the minimal resistance......Single RF MIMO communication emerges a novel low cost communication method which does not consume as much power as the conventional MIMO. The implementation of such single RF MIMO system is done by mapping the weighting factors to the polarizations or the radiation patterns of the antennas...

  18. Changes in agricultural cropland areas between a water-surplus year and a water-deficit year impacting food security, determined using MODIS 250 m time-series data and spectral matching techniques, in the Krishna river basin (India)

    Science.gov (United States)

    Gumma, Murali Krishna; Thenkabail, Prasad S.; Muralikrishna, I.V.; Velpuri, Naga Manohar; Gangadhararao, P.T.; Dheeravath, V.; Biradar, C.M.; Nalan, S.A.; Gaur, A.

    2011-01-01

    The objective of this study was to investigate the changes in cropland areas as a result of water availability using Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m time-series data and spectral matching techniques (SMTs). The study was conducted in the Krishna River basin in India, a very large river basin with an area of 265 752 km2 (26 575 200 ha), comparing a water-surplus year (2000–2001) and a water-deficit year (2002–2003). The MODIS 250 m time-series data and SMTs were found ideal for agricultural cropland change detection over large areas and provided fuzzy classification accuracies of 61–100% for various land‐use classes and 61–81% for the rain-fed and irrigated classes. The most mixing change occurred between rain-fed cropland areas and informally irrigated (e.g. groundwater and small reservoir) areas. Hence separation of these two classes was the most difficult. The MODIS 250 m-derived irrigated cropland areas for the districts were highly correlated with the Indian Bureau of Statistics data, with R 2-values between 0.82 and 0.86.The change in the net area irrigated was modest, with an irrigated area of 8 669 881 ha during the water-surplus year, as compared with 7 718 900 ha during the water-deficit year. However, this is quite misleading as most of the major changes occurred in cropping intensity, such as changing from higher intensity to lower intensity (e.g. from double crop to single crop). The changes in cropping intensity of the agricultural cropland areas that took place in the water-deficit year (2002–2003) when compared with the water-surplus year (2000–2001) in the Krishna basin were: (a) 1 078 564 ha changed from double crop to single crop, (b) 1 461 177 ha changed from continuous crop to single crop, (c) 704 172 ha changed from irrigated single crop to fallow and (d) 1 314 522 ha changed from minor irrigation (e.g. tanks, small reservoirs) to rain-fed. These are highly significant changes that will

  19. Approaches for Stereo Matching

    Directory of Open Access Journals (Sweden)

    Takouhi Ozanian

    1995-04-01

    Full Text Available This review focuses on the last decade's development of the computational stereopsis for recovering three-dimensional information. The main components of the stereo analysis are exposed: image acquisition and camera modeling, feature selection, feature matching and disparity interpretation. A brief survey is given of the well known feature selection approaches and the estimation parameters for this selection are mentioned. The difficulties in identifying correspondent locations in the two images are explained. Methods as to how effectively to constrain the search for correct solution of the correspondence problem are discussed, as are strategies for the whole matching process. Reasons for the occurrence of matching errors are considered. Some recently proposed approaches, employing new ideas in the modeling of stereo matching in terms of energy minimization, are described. Acknowledging the importance of computation time for real-time applications, special attention is paid to parallelism as a way to achieve the required level of performance. The development of trinocular stereo analysis as an alternative to the conventional binocular one, is described. Finally a classification based on the test images for verification of the stereo matching algorithms, is supplied.

  20. MR angiography with a matched filter

    International Nuclear Information System (INIS)

    De Castro, J.B.; Riederer, S.J.; Lee, J.N.

    1987-01-01

    The technique of matched filtering was applied to a series of cine MR images. The filter was devised to yield a subtraction angiographic image in which direct current components present in the cine series are removed and the signal-to-noise ratio (S/N) of the vascular structures is optimized. The S/N of a matched filter was compared with that of a simple subtraction, in which an image with high flow is subtracted from one with low flow. Experimentally, a range of results from minimal improvement to significant (60%) improvement in S/N was seen in the comparisons of matched filtered subtraction with simple subtraction

  1. A Template Matching Method of Wideband Sonar Detection

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J Y; Zhong, X P; Feng, X Z [College of Mechatronics Engineering and Automation National University of Defense Technology ChangSha, HuNan (China)

    2006-10-15

    Advances in computer memory, computation speed, and transducer bandwidth have made possible higher Time-Bandwidth product (TB) transmit signals and will bring out higher resolutions. In this paper a new method is proposed to estimation Doppler velocity base on correlation analysis and mode matching in wideband condition instead of wideband matched filter. Paper use mode-matching principle to search appropriate scaled factor matrix. Simulation showing this method has well restrains noise capability and perfect calculation stability; the amount of compute can be decreased greatly by scaled factor matrix computed in advance.

  2. A Template Matching Method of Wideband Sonar Detection

    International Nuclear Information System (INIS)

    Chen, J Y; Zhong, X P; Feng, X Z

    2006-01-01

    Advances in computer memory, computation speed, and transducer bandwidth have made possible higher Time-Bandwidth product (TB) transmit signals and will bring out higher resolutions. In this paper a new method is proposed to estimation Doppler velocity base on correlation analysis and mode matching in wideband condition instead of wideband matched filter. Paper use mode-matching principle to search appropriate scaled factor matrix. Simulation showing this method has well restrains noise capability and perfect calculation stability; the amount of compute can be decreased greatly by scaled factor matrix computed in advance

  3. Schema matching and mapping

    CERN Document Server

    Bellahsene, Zohra; Rahm, Erhard

    2011-01-01

    Requiring heterogeneous information systems to cooperate and communicate has now become crucial, especially in application areas like e-business, Web-based mash-ups and the life sciences. Such cooperating systems have to automatically and efficiently match, exchange, transform and integrate large data sets from different sources and of different structure in order to enable seamless data exchange and transformation. The book edited by Bellahsene, Bonifati and Rahm provides an overview of the ways in which the schema and ontology matching and mapping tools have addressed the above requirements

  4. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    2001-01-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to current 3D codes that simulate binary black holes. A prime application of characteristic evolution is Cauchy-characteristic matching, which is also reviewed.

  5. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    1998-05-01

    Full Text Available We review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to current 3D black hole codes that run forever. A prime application of characteristic evolution is Cauchy-characteristic matching, which is also reviewed.

  6. Factorized Graph Matching.

    Science.gov (United States)

    Zhou, Feng; de la Torre, Fernando

    2015-11-19

    Graph matching (GM) is a fundamental problem in computer science, and it plays a central role to solve correspondence problems in computer vision. GM problems that incorporate pairwise constraints can be formulated as a quadratic assignment problem (QAP). Although widely used, solving the correspondence problem through GM has two main limitations: (1) the QAP is NP-hard and difficult to approximate; (2) GM algorithms do not incorporate geometric constraints between nodes that are natural in computer vision problems. To address aforementioned problems, this paper proposes factorized graph matching (FGM). FGM factorizes the large pairwise affinity matrix into smaller matrices that encode the local structure of each graph and the pairwise affinity between edges. Four are the benefits that follow from this factorization: (1) There is no need to compute the costly (in space and time) pairwise affinity matrix; (2) The factorization allows the use of a path-following optimization algorithm, that leads to improved optimization strategies and matching performance; (3) Given the factorization, it becomes straight-forward to incorporate geometric transformations (rigid and non-rigid) to the GM problem. (4) Using a matrix formulation for the GM problem and the factorization, it is easy to reveal commonalities and differences between different GM methods. The factorization also provides a clean connection with other matching algorithms such as iterative closest point; Experimental results on synthetic and real databases illustrate how FGM outperforms state-of-the-art algorithms for GM. The code is available at http://humansensing.cs.cmu.edu/fgm.

  7. Matching to Openly Innovate with Suppliers

    DEFF Research Database (Denmark)

    Laursen, Linda Nhu

    2017-01-01

    heterogeneous suppliers with the internal organisation in order to openly innovate. More specifically, it focuses on a governance mode, recently emerged in practice, by which firms summon their suppliers and their own internal organisation at an event to match them for open innovation activities – innovation......When large firms choose to involve their many suppliers in open innovation, they are faced with a set of challenges pertaining to the governance of several suppliers. Suppliers are heterogeneous, offering heterogeneous materials, products, information, services, and knowledge, which are differently...... organized across functions and hierarchies. To make use of such heterogeneous resources, a critical challenge for open innovation is to pair a supplier resource with a suitable opportunity-for-use from within the firm – a challenge of matching. This dissertation addresses the challenge of matching...

  8. Matching Supernovae to Galaxies

    Science.gov (United States)

    Kohler, Susanna

    2016-12-01

    developed a new automated algorithm for matching supernovae to their host galaxies. Their work builds on currently existing algorithms and makes use of information about the nearby galaxies, accounts for the uncertainty of the match, and even includes a machine learning component to improve the matching accuracy.Gupta and collaborators test their matching algorithm on catalogs of galaxies and simulated supernova events to quantify how well the algorithm is able to accurately recover the true hosts.Successful MatchingThe matching algorithms accuracy (purity) as a function of the true supernova-host separation, the supernova redshift, the true hosts brightness, and the true hosts size. [Gupta et al. 2016]The authors find that when the basic algorithm is run on catalog data, it matches supernovae to their hosts with 91% accuracy. Including the machine learning component, which is run after the initial matching algorithm, improves the accuracy of the matching to 97%.The encouraging results of this work which was intended as a proof of concept suggest that methods similar to this could prove very practical for tackling future survey data. And the method explored here has use beyond matching just supernovae to their host galaxies: it could also be applied to other extragalactic transients, such as gamma-ray bursts, tidal disruption events, or electromagnetic counterparts to gravitational-wave detections.CitationRavi R. Gupta et al 2016 AJ 152 154. doi:10.3847/0004-6256/152/6/154

  9. [Propensity score matching in SPSS].

    Science.gov (United States)

    Huang, Fuqiang; DU, Chunlin; Sun, Menghui; Ning, Bing; Luo, Ying; An, Shengli

    2015-11-01

    To realize propensity score matching in PS Matching module of SPSS and interpret the analysis results. The R software and plug-in that could link with the corresponding versions of SPSS and propensity score matching package were installed. A PS matching module was added in the SPSS interface, and its use was demonstrated with test data. Score estimation and nearest neighbor matching was achieved with the PS matching module, and the results of qualitative and quantitative statistical description and evaluation were presented in the form of a graph matching. Propensity score matching can be accomplished conveniently using SPSS software.

  10. Outsourced pattern matching

    DEFF Research Database (Denmark)

    Faust, Sebastian; Hazay, Carmit; Venturi, Daniele

    2013-01-01

    In secure delegatable computation, computationally weak devices (or clients) wish to outsource their computation and data to an untrusted server in the cloud. While most earlier work considers the general question of how to securely outsource any computation to the cloud server, we focus...... and the client C T in order to learn the positions at which a pattern of length m matches the text (and nothing beyond that). This is called the outsourced pattern matching problem and is highly motivated in the context of delegatable computing since it offers storage alternatives for massive databases...... that contain confidential data (e.g., health related data about patient history). Our constructions offer simulation-based security in the presence of semi-honest and malicious adversaries (in the random oracle model) and limit the communication in the query phase to O(m) bits plus the number of occurrences...

  11. Bayesian grid matching

    DEFF Research Database (Denmark)

    Hartelius, Karsten; Carstensen, Jens Michael

    2003-01-01

    A method for locating distorted grid structures in images is presented. The method is based on the theories of template matching and Bayesian image restoration. The grid is modeled as a deformable template. Prior knowledge of the grid is described through a Markov random field (MRF) model which...... represents the spatial coordinates of the grid nodes. Knowledge of how grid nodes are depicted in the observed image is described through the observation model. The prior consists of a node prior and an arc (edge) prior, both modeled as Gaussian MRFs. The node prior models variations in the positions of grid...... nodes and the arc prior models variations in row and column spacing across the grid. Grid matching is done by placing an initial rough grid over the image and applying an ensemble annealing scheme to maximize the posterior distribution of the grid. The method can be applied to noisy images with missing...

  12. Electromagnetic wave matching device

    International Nuclear Information System (INIS)

    Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.

    1997-01-01

    The present invention provides a matching device capable of increasing an efficiency of combining beams of electromagnetic waves outputted from an output window of a gyrotron which is expected for plasma heating of a thermonuclear reactor and an electromagnetic wave transmission system as high as possible. Namely, an electromagnetic wave matching device reflects beams of electromagnetic waves incident from an inlet by a plurality of phase correction mirrors and combines them to an external transmission system through an exit. In this case, the phase correction mirrors change the phase of the beams of electromagnetic waves incident to the phase correction mirrors by a predetermined amount corresponding to the position of the reflection mirrors. Then, the beams of electromagnetic waves outputted, for example, from a gyrotron can properly be shaped as desired for the intensity and the phase. As a result, combination efficiency with the transmission system can be increased. (I.S.)

  13. Applying Failure Modes, Effects, And Criticality Analysis And Human Reliability Analysis Techniques To Improve Safety Design Of Work Process In Singapore Armed Forces

    Science.gov (United States)

    2016-09-01

    suitable for this work process. Table 18 shows a comparison of the advantages and disadvantages for the remaining HRA methods. 47 Table 18. Comparison...aims to study the feasibility of adopting HEART as an alternate hazard assessment technique for human-centric work processes. 10 B. METHODOLOGY...of THERP, HEART, and SPAR-H. Adapted from Bell and Holroyd (2009). Advantages Disadvantages THERP - THERP is well used in practice - It has a

  14. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    2005-12-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. A prime application of characteristic evolution is to compute waveforms via Cauchy-characteristic matching, which is also reviewed.

  15. A review on compressed pattern matching

    Directory of Open Access Journals (Sweden)

    Surya Prakash Mishra

    2016-09-01

    Full Text Available Compressed pattern matching (CPM refers to the task of locating all the occurrences of a pattern (or set of patterns inside the body of compressed text. In this type of matching, pattern may or may not be compressed. CPM is very useful in handling large volume of data especially over the network. It has many applications in computational biology, where it is useful in finding similar trends in DNA sequences; intrusion detection over the networks, big data analytics etc. Various solutions have been provided by researchers where pattern is matched directly over the uncompressed text. Such solution requires lot of space and consumes lot of time when handling the big data. Various researchers have proposed the efficient solutions for compression but very few exist for pattern matching over the compressed text. Considering the future trend where data size is increasing exponentially day-by-day, CPM has become a desirable task. This paper presents a critical review on the recent techniques on the compressed pattern matching. The covered techniques includes: Word based Huffman codes, Word Based Tagged Codes; Wavelet Tree Based Indexing. We have presented a comparative analysis of all the techniques mentioned above and highlighted their advantages and disadvantages.

  16. Multi-Mode Vibration Suppression in MIMO Systems by Extending the Zero Placement Input Shaping Technique: Applications to a 3-DOF Piezoelectric Tube Actuator

    Directory of Open Access Journals (Sweden)

    Yasser Al Hamidi

    2016-04-01

    Full Text Available Piezoelectric tube actuators are extensively used in scanning probe microscopes to provide dynamic scanning motions in open-loop operations. Furthermore, they are employed as micropositioners due to their high bandwidth, high resolution and ease of excitation. However, these piezoelectric micropositioners exhibit badly damped vibrations that occur when the input excites the dynamic response, which tends to degrade positioning accuracy and performance. This paper deals with vibrations’ feedforward control of a multi-degrees of freedom (DOF piezoelectric micropositioner in order to damp the vibrations in the direct axes and to reduce the cross-couplings. The novelty in this paper relative to the existing vibrations feedforward controls is the simplicity in design approach, the minimal number of shaper impulses for each input required to damp all modes of vibration at each output, and the account for the strong cross-couplings which only occur in multi-DOF cases. A generalization to a multiple degrees of freedom actuator is first proposed. Then simulation runs on a 3-DOF piezoelectric tube micropositioner have been effectuated to demonstrate the efficiency of the proposed method. Finally, experimental tests were carried out to validate and to confirm the predicted simulation.

  17. Computer-Generated Holographic Matched Filters

    Science.gov (United States)

    Butler, Steven Frank

    This dissertation presents techniques for the use of computer-generated holograms (CGH) for matched filtering. An overview of the supporting technology is provided. Included are techniques for modifying existing CGH algorithms to serve as matched filters in an optical correlator. It shows that matched filters produced in this fashion can be modified to improve the signal-to-noise and efficiency over that possible with conventional holography. The effect and performance of these modifications are demonstrated. In addition, a correction of film non-linearity in continuous -tone filter production is developed. Computer simulations provide quantitative and qualitative demonstration of theoretical principles, with specific examples validated in optical hardware. Conventional and synthetic holograms, both bleached and unbleached, are compared.

  18. Contemporary modes of marketing research

    Directory of Open Access Journals (Sweden)

    Radunović Ivana

    2008-01-01

    Full Text Available Paper is oriented to presentation of modern or contemporary marketing research modes of techniques. Based on personal experience, author pointed out the basic advantages or frailer of individually treated modes - from CATI to Hi-Tech observation approaches.

  19. Solvent Front Position Extraction procedure with thin-layer chromatography as a mode of multicomponent sample preparation for quantitative analysis by instrumental technique.

    Science.gov (United States)

    Klimek-Turek, A; Sikora, E; Dzido, T H

    2017-12-29

    A concept of using thin-layer chromatography to multicomponent sample preparation for quantitative determination of solutes followed by instrumental technique is presented. Thin-layer chromatography (TLC) is used to separate chosen substances and their internal standard from other components (matrix) and to form a single spot/zone containing them at the solvent front position. The location of the analytes and internal standard in the solvent front zone allows their easy extraction followed by quantitation by HPLC. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Using the Internet to Promote Health Behavior Change: A Systematic Review and Meta-analysis of the Impact of Theoretical Basis, Use of Behavior Change Techniques, and Mode of Delivery on Efficacy

    Science.gov (United States)

    Joseph, Judith; Yardley, Lucy; Michie, Susan

    2010-01-01

    Background The Internet is increasingly used as a medium for the delivery of interventions designed to promote health behavior change. However, reviews of these interventions to date have not systematically identified intervention characteristics and linked these to effectiveness. Objectives The present review sought to capitalize on recently published coding frames for assessing use of theory and behavior change techniques to investigate which characteristics of Internet-based interventions best promote health behavior change. In addition, we wanted to develop a novel coding scheme for assessing mode of delivery in Internet-based interventions and also to link different modes to effect sizes. Methods We conducted a computerized search of the databases indexed by ISI Web of Knowledge (including BIOSIS Previews and Medline) between 2000 and 2008. Studies were included if (1) the primary components of the intervention were delivered via the Internet, (2) participants were randomly assigned to conditions, and (3) a measure of behavior related to health was taken after the intervention. Results We found 85 studies that satisfied the inclusion criteria, providing a total sample size of 43,236 participants. On average, interventions had a statistically small but significant effect on health-related behavior (d+ = 0.16, 95% CI 0.09 to 0.23). More extensive use of theory was associated with increases in effect size (P = .049), and, in particular, interventions based on the theory of planned behavior tended to have substantial effects on behavior (d+ = 0.36, 95% CI 0.15 to 0.56). Interventions that incorporated more behavior change techniques also tended to have larger effects compared to interventions that incorporated fewer techniques (P Internet-based interventions was enhanced by the use of additional methods of communicating with participants, especially the use of short message service (SMS), or text, messages. Conclusions The review provides a framework for the

  1. Using the internet to promote health behavior change: a systematic review and meta-analysis of the impact of theoretical basis, use of behavior change techniques, and mode of delivery on efficacy.

    Science.gov (United States)

    Webb, Thomas L; Joseph, Judith; Yardley, Lucy; Michie, Susan

    2010-02-17

    The Internet is increasingly used as a medium for the delivery of interventions designed to promote health behavior change. However, reviews of these interventions to date have not systematically identified intervention characteristics and linked these to effectiveness. The present review sought to capitalize on recently published coding frames for assessing use of theory and behavior change techniques to investigate which characteristics of Internet-based interventions best promote health behavior change. In addition, we wanted to develop a novel coding scheme for assessing mode of delivery in Internet-based interventions and also to link different modes to effect sizes. We conducted a computerized search of the databases indexed by ISI Web of Knowledge (including BIOSIS Previews and Medline) between 2000 and 2008. Studies were included if (1) the primary components of the intervention were delivered via the Internet, (2) participants were randomly assigned to conditions, and (3) a measure of behavior related to health was taken after the intervention. We found 85 studies that satisfied the inclusion criteria, providing a total sample size of 43,236 participants. On average, interventions had a statistically small but significant effect on health-related behavior (d(+) = 0.16, 95% CI 0.09 to 0.23). More extensive use of theory was associated with increases in effect size (P = .049), and, in particular, interventions based on the theory of planned behavior tended to have substantial effects on behavior (d(+) = 0.36, 95% CI 0.15 to 0.56). Interventions that incorporated more behavior change techniques also tended to have larger effects compared to interventions that incorporated fewer techniques (P Internet-based interventions was enhanced by the use of additional methods of communicating with participants, especially the use of short message service (SMS), or text, messages. The review provides a framework for the development of a science of Internet

  2. Failure Modes

    DEFF Research Database (Denmark)

    Jakobsen, K. P.; Burcharth, H. F.; Ibsen, Lars Bo

    1999-01-01

    The present appendix contains the derivation of ten different limit state equations divided on three different failure modes. Five of the limit state equations can be used independently of the characteristics of the subsoil, whereas the remaining five can be used for either drained or undrained...

  3. Dual-Mode Combined Infra Red and Air-Coupled Ultrasonic Technique for Real-Time Industrial Process Control with Special Reference to the Food Industry

    Science.gov (United States)

    Pallav, P.; Hutchins, D. A.; Diamond, G. G.; Gan, T. H.; Hellyer, J. E.

    2008-02-01

    This paper describes the use of air-coupled ultrasound and Near Infra red (NIR) as complimentary techniques for food quality assessment. A major study has been performed, in collaboration with four industrial food companies, to investigate the use of air-coupled ultrasound and NIR to both detect foreign bodies, and to measure certain parameters of interest, such as the amount of a certain additive. The research has demonstrated that air-coupled ultrasound can be used in on-line situations, measuring food materials such as chocolate and cheese. It is also capable of performing measurements on moving sealed metal cans containing food, and is able to detect foreign bodies with the top removed, as encountered just before sealing. NIR has been used as a complimentary technique to test food materials where propagation of air-coupled ultrasound was found to be difficult. This could be due to the presence of air pockets within the food material, as in the case of bread dough.

  4. Parametric Landau damping of space charge modes

    Energy Technology Data Exchange (ETDEWEB)

    Macridin, Alexandru [Fermilab; Burov, Alexey [Fermilab; Stern, Eric [Fermilab; Amundson, James [Fermilab; Spentzouris, Panagiotis [Fermilab

    2016-09-23

    Landau damping is the mechanism of plasma and beam stabilization; it arises through energy transfer from collective modes to the incoherent motion of resonant particles. Normally this resonance requires the resonant particle's frequency to match the collective mode frequency. We have identified an important new damping mechanism, parametric Landau damping, which is driven by the modulation of the mode-particle interaction. This opens new possibilities for stability control through manipulation of both particle and mode-particle coupling spectra. We demonstrate the existence of parametric Landau damping in a simulation of transverse coherent modes of bunched accelerator beams with space charge.

  5. Accurate mode characterization of two-mode optical fibers by in-fiber acousto-optics.

    Science.gov (United States)

    Alcusa-Sáez, E; Díez, A; Andrés, M V

    2016-03-07

    Acousto-optic interaction in optical fibers is exploited for the accurate and broadband characterization of two-mode optical fibers. Coupling between LP 01 and LP 1m modes is produced in a broadband wavelength range. Difference in effective indices, group indices, and chromatic dispersions between the guided modes, are obtained from experimental measurements. Additionally, we show that the technique is suitable to investigate the fine modes structure of LP modes, and some other intriguing features related with modes' cut-off.

  6. Scalable Multigigabit Pattern Matching for Packet Inspection

    NARCIS (Netherlands)

    Sourdis, I.; Pnevmatikatos, D.N.; Vassiliadis, S.

    2007-01-01

    In this paper, we consider hardware-based scanning and analyzing packets payload in order to detect hazardous contents.We present two pattern matching techniques to compare incoming packets against intrusion detection search patterns. The first approach, decoded partial CAM (DpCAM), predecodes

  7. PATTERN MATCHING IN MODELS

    Directory of Open Access Journals (Sweden)

    Cristian GEORGESCU

    2005-01-01

    Full Text Available The goal of this paper is to investigate how such a pattern matching could be performed on models,including the definition of the input language as well as the elaboration of efficient matchingalgorithms. Design patterns can be considered reusable micro-architectures that contribute to anoverall system architecture. Frameworks are also closely related to design patterns. Componentsoffer the possibility to radically change the behaviors and services offered by an application bysubstitution or addition of new components, even a long time after deployment. Software testing isanother aspect of reliable development. Testing activities mainly consist in ensuring that a systemimplementation conforms to its specifications.

  8. Plasma focus matching conditions

    International Nuclear Information System (INIS)

    Soliman, H.M.; Masoud, M.M.; Elkhalafawy, T.A.

    1988-01-01

    A snow-plough and slug models have been used to obtain the optimum matching conditions of the plasma in the focus. The dimensions of the plasma focus device are, inner electrode radius = 2 cm, outer electrode radius = 5.5 cm, and its length = 8 cm. It was found that the maximum magnetic energy of 12.26 kJ has to be delivered to plasma focus whose density is 10 19 /cm 3 at focusing time of 2.55 μs and with total external inductance of 24.2 n H. The same method is used to evaluate the optimum matching conditions for the previous coaxial discharge system which had inner electrode radius = 1.6 cm, outer electrode radius = 3.3 cm and its length = 31.5 cm. These conditions are charging voltage = 12 kV, capacity of the condenser bank = 430 μf, plasma focus density = 10 19 /cm 3 focusing time = 8 μs and total external inductance = 60.32 n H.3 fig., 2 tab

  9. Match analysis on no-gi Brazilian jiu-jitsu

    OpenAIRE

    Simola, Tuomas

    2017-01-01

    Gi and no-gi Brazilian jiu-jitsu are fast growing sports. The aim of this thesis is to conclude a match analysis on no-gi Brazilian jiu-jitsu. Match analysis is used to identify the most used techniques in no-gi Brazilian jiu-jitsu. There is no sport analysis done for either gi or no-gi Brazilian jiu-jitsu, therefore the match analysis and its results can be utilized later as a base for sport analysis. The goal of this study is to find out the match duration, the type of match ending, the...

  10. Observation of energy oscillation between strongly-coupled counter-propagating ultra-high Q whispering gallery modes.

    Science.gov (United States)

    Yoshiki, Wataru; Chen-Jinnai, Akitoshi; Tetsumoto, Tomohiro; Tanabe, Takasumi

    2015-11-30

    We report the first experimental observation of an energy oscillation between two coupled ultra-high Q whispering gallery modes in the time domain. Two counter-propagating whispering gallery modes in a silica toroid microcavity were employed for this purpose. The combination of a large coupling coefficient between the two modes and an ultra-high Q factor, which creates a large Γ value of > 10, results in a clear energy oscillation. Our measurement is based on a drop-port measurement technique, which enables us to observe the light energy in the two modes directly. The oscillation period measured in the time domain precisely matched that inferred from mode splitting in the frequency domain, and the measured results showed excellent agreement with results calculated with the developed numerical model.

  11. Experimental Study on Corrosion Detection of Aluminum Alloy Using Lamb Wave Mixing Technique

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Heeung; Lee, Jaesun; Cho, Younho [Pusan Nat’l Univ., Busan (Korea, Republic of)

    2016-11-15

    In this study, the Lamb wave mixing technique, which is basised on advanced research on the nonlinear bulk wave mixing technique, is applied for corrosion detection. To demonstrate the validity of the Lamb wave mixing technique, an experiment was performed with normal and corroded specimens. Comparison group in an experimentation are selected to mode and frequency with dominant in-plane displacement and out-of-plane displacement of Lamb waves. The results showed that the Lamb wave mixing technique can monitor corrosion defects, and it has a trend similar to that of the conventional Lamb wave technique. It was confirmed that the dominant displacement and mode matching the theory were generated. Flaw detectability is determined depending on displacement ratio instead of using the measurement method and mode selection.

  12. 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...

  13. Job Searchers, Job Matches and the Elasticity of Matching

    NARCIS (Netherlands)

    Broersma, L.; van Ours, J.C.

    1998-01-01

    This paper stresses the importance of a specification of the matching function in which the measure of job matches corresponds to the measure of job searchers. In many empirical studies on the matching function this requirement has not been fulfilled because it is difficult to find information about

  14. Development of a hybrid mode linear transformer driver stage

    Science.gov (United States)

    Zhang, Le; Wang, Meng; Zhou, Liangji; Tian, Qing; Guo, Fan; Wang, Lingyun; Qing, Yanling; Zhao, Yue; Dai, Yingmin; Han, Wenhui; Chen, Lin; Xie, Weiping

    2018-02-01

    At present, the mainstream technologies of primary power sources of large pulse power devices adopt Marx or linear transformer driver (LTD) designs. Based on the analysis of the characteristics of these two types of circuit topologies, the concept of a hybrid mode LTD stage based on Marx branches is proposed. The analysis shows that the hybrid mode LTD stage can realize the following goals: (a) to reduce the energy and power handled by the basic components (switch and capacitor) to lengthen their lifetime; (b) to reduce the requirements of the multipath synchronous trigger system; and (c) to improve the maintainability of the LTD stage by using independent Marx generators instead of "traditional LTD bricks." To verify the technique, a hybrid mode LTD stage consisting of 50 branches (four-stage compact Marx generators) was designed, manufactured and tested. The stage has a radius of about 3.3 m and a height of 0.6 m. The single Marx circuit's load current is about 21 kA, with a rise time of ˜90 ns (10%-90%), under the conditions of capacitors charged to ±40 kV and a 6.9 Ω matched load. The whole stage's load current is ˜1 MA , with a rise time of ˜112 ns (10%-90%), when the capacitors are charged to ±45 kV and the matched load is 0.14 Ω .

  15. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    2009-04-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to eliminate the role of this artificial outer boundary via Cauchy-characteristic matching, by which the radiated waveform can be computed at null infinity. Progress in this direction is discussed.

  16. Electromagnetic wave matching device

    International Nuclear Information System (INIS)

    Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.

    1997-01-01

    The present invention provides an electromagnetic wave matching capable of reducing a cost for the transmission system in a system of using electromagnetic waves for plasma heating of a thermonuclear reactor. Namely, incident electromagnetic waves are reflected by using a plurality of phase correction mirrors. The reflected electromagnetic waves are connected to an external transmission system through an exit. The phase correction mirrors have such a shape to receive a plurality of beam-like electromagnetic waves and output electromagnetic waves by the number different from the number of the received electromagnetic wave beams having a predetermined distribution. Further, at least two of the phase correction mirrors have such a shape to change the phase of the electromagnetic waves beams incident to the reflection surface of the phase correction mirrors by a predetermined amount corresponding to the position of the reflection surface. Then, the cost for transmission system can greatly be reduced. (I.S.)

  17. Quantity precommitment and price matching

    DEFF Research Database (Denmark)

    Tumennasan, Norovsambuu

    We revisit the question of whether price matching is anti-competitive in a capacity constrained duopoly setting. We show that the effect of price matching depends on capacity. Specifically, price matching has no effect when capacity is relatively low, but it benefits the firms when capacity...... is relatively high. Interestingly, when capacity is in an intermediate range, price matching benefits only the small firm but does not affect the large firm in any way. Therefore, one has to consider capacity seriously when evaluating if price matching is anti-competitive. If the firms choose their capacities...... simultaneously before pricing decisions, then the effect of price matching is either pro-competitive or ambiguous. We show that if the cost of capacity is high, then price matching can only (weakly) decrease the market price. On the other hand, if the cost of capacity is low, then the effect of price matching...

  18. Quantum optomechanics with a high-frequency dilational mode in thin dielectric membranes

    Science.gov (United States)

    Børkje, K.; Girvin, S. M.

    2012-08-01

    The interaction between a high-frequency dilational mode of a thin dielectric film and an optical cavity field is studied theoretically in the membrane-in-the-middle setup. A derivation from first principles leads to a multi-mode optomechanical Hamiltonian where multiple cavity modes are coupled by the thickness variation of the membrane. For membrane thicknesses of the order of 1 μm, the frequency of this dilational mode is in the GHz range. This can be matched to the free spectral range of the optical cavity, such that the mechanical oscillator will resonantly couple cavity modes at different frequencies. Furthermore, such a large mechanical frequency also means that the quantum ground state of motion can be reached with conventional refrigeration techniques. Estimation of the coupling strength with realistic parameters suggests that optomechanical effects can be observable with this dilational mode. It is shown how this system can be used as a quantum limited optical amplifier. The dilational motion can also lead to quantum correlations between cavity modes at different frequencies, which is quantified with an experimentally accessible two-mode squeezing spectrum. Finally, an explicit signature of radiation pressure shot noise in this system is identified.

  19. Linguistic identity matching

    CERN Document Server

    Lisbach, Bertrand

    2013-01-01

    Regulation, risk awareness and technological advances are increasingly drawing identity search functionality into business, security and data management processes, as well as fraud investigations and counter-terrorist measures.Over the years, a number of techniques have been developed for searching identity data, traditionally focusing on logical algorithms. These techniques often failed to take into account the complexities of language and culture that provide the rich variations  seen in names used around the world. A new paradigm has now emerged for understanding the way that identity data

  20. Planar quadrature RF transceiver design using common-mode differential-mode (CMDM transmission line method for 7T MR imaging.

    Directory of Open Access Journals (Sweden)

    Ye Li

    Full Text Available The use of quadrature RF magnetic fields has been demonstrated to be an efficient method to reduce transmit power and to increase the signal-to-noise (SNR in magnetic resonance (MR imaging. The goal of this project was to develop a new method using the common-mode and differential-mode (CMDM technique for compact, planar, distributed-element quadrature transmit/receive resonators for MR signal excitation and detection and to investigate its performance for MR imaging, particularly, at ultrahigh magnetic fields. A prototype resonator based on CMDM method implemented by using microstrip transmission line was designed and fabricated for 7T imaging. Both the common mode (CM and the differential mode (DM of the resonator were tuned and matched at 298MHz independently. Numerical electromagnetic simulation was performed to verify the orthogonal B1 field direction of the two modes of the CMDM resonator. Both workbench tests and MR imaging experiments were carried out to evaluate the performance. The intrinsic decoupling between the two modes of the CMDM resonator was demonstrated by the bench test, showing a better than -36 dB transmission coefficient between the two modes at resonance frequency. The MR images acquired by using each mode and the images combined in quadrature showed that the CM and DM of the proposed resonator provided similar B1 coverage and achieved SNR improvement in the entire region of interest. The simulation and experimental results demonstrate that the proposed CMDM method with distributed-element transmission line technique is a feasible and efficient technique for planar quadrature RF coil design at ultrahigh fields, providing intrinsic decoupling between two quadrature channels and high frequency capability. Due to its simple and compact geometry and easy implementation of decoupling methods, the CMDM quadrature resonator can possibly be a good candidate for design blocks in multichannel RF coil arrays.

  1. Matching Jobs and Resumes: a Deep Collaborative Filtering Task

    OpenAIRE

    Schmitt , Thomas; Caillou , Philippe; Sebag , Michèle

    2016-01-01

    International audience; This paper tackles the automatic matching of job seekers and recruiters, based on the logs of a recruitment agency (CVs, job announcements and application clicks). Preliminary experiments reveal that good recommendation performances in collaborative filtering mode (emitting recommendations for a known recruiter using the click history) co-exist with poor performances in cold start mode (emitting recommendations based on the job announcement only). A tentative interpret...

  2. Matchings with Externalities and Attitudes

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal

    2013-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas...... fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. Under this framework, we analyze many-to-many matchings and one-to-one matchings...

  3. Using crosswell data to enhance history matching

    KAUST Repository

    Ravanelli, Fabio M.

    2014-01-01

    One of the most challenging tasks in the oil industry is the production of reliable reservoir forecast models. Due to different sources of uncertainties in the numerical models and inputs, reservoir simulations are often only crude approximations of the reality. This problem is mitigated by conditioning the model with data through data assimilation, a process known in the oil industry as history matching. Several recent advances are being used to improve history matching reliability, notably the use of time-lapse data and advanced data assimilation techniques. One of the most promising data assimilation techniques employed in the industry is the ensemble Kalman filter (EnKF) because of its ability to deal with non-linear models at reasonable computational cost. In this paper we study the use of crosswell seismic data as an alternative to 4D seismic surveys in areas where it is not possible to re-shoot seismic. A synthetic reservoir model is used in a history matching study designed better estimate porosity and permeability distributions and improve the quality of the model to predict future field performance. This study is divided in three parts: First the use of production data only is evaluated (baseline for benchmark). Second the benefits of using production and 4D seismic data are assessed. Finally, a new conceptual idea is proposed to obtain time-lapse information for history matching. The use of crosswell time-lapse seismic tomography to map velocities in the interwell region is demonstrated as a potential tool to ensure survey reproducibility and low acquisition cost when compared with full scale surface surveys. Our numerical simulations show that the proposed method provides promising history matching results leading to similar estimation error reductions when compared with conventional history matched surface seismic data.

  4. Organizations must match assets

    International Nuclear Information System (INIS)

    Carley, G.R.

    1991-01-01

    The unprofitable state of the Canadian oil industry, the adverse economic environment, the difficulty of finding capital, and the diminishing resources of conventional lighter crude oil make it necessary for Canadian oil companies to match their organizations and their financing to their assets. This is illustrated according to the experience of Saskoil, a Saskatchewan oil and gas company. An increasing production of oil and natural gas, and an increasing amount of new oil production as heavy oil, led to organizational changes such as the purchase of an asphalt plant to provide the company with downstream experience, establishing a working group to explore and develop heavy oil resources, and forming a company to manage non-core assets. The latter company, Pasqua Resources, manages assets such as small properties and ownership interests in order to increase the operating efficiency of Saskoil. Pasqua provides Saskoil with a corporate and organizational vehicle to accommodate partnerships and joint venture capital invested in property purchase opportunities, and to manage any of Saskoil's divestiture activities

  5. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Jeffrey Winicour

    2012-01-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial-value problem. Progress in characteristic evolution is traced from the early stage of 1D feasibility studies to 2D-axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black-hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black-hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to extend such simulations to null infinity where the waveform from the binary inspiral and merger can be unambiguously computed. This has now been accomplished by Cauchy-characteristic extraction, where data for the characteristic evolution is supplied by Cauchy data on an extraction worldtube inside the artificial outer boundary. The ultimate application of characteristic evolution is to eliminate the role of this outer boundary by constructing a global solution via Cauchy-characteristic matching. Progress in this direction is discussed.

  6. Global Patch Matching

    Science.gov (United States)

    Huang, X.; Hu, K.; Ling, X.; Zhang, Y.; Lu, Z.; Zhou, G.

    2017-09-01

    This paper introduces a novel global patch matching method that focuses on how to remove fronto-parallel bias and obtain continuous smooth surfaces with assuming that the scenes covered by stereos are piecewise continuous. Firstly, simple linear iterative cluster method (SLIC) is used to segment the base image into a series of patches. Then, a global energy function, which consists of a data term and a smoothness term, is built on the patches. The data term is the second-order Taylor expansion of correlation coefficients, and the smoothness term is built by combing connectivity constraints and the coplanarity constraints are combined to construct the smoothness term. Finally, the global energy function can be built by combining the data term and the smoothness term. We rewrite the global energy function in a quadratic matrix function, and use least square methods to obtain the optimal solution. Experiments on Adirondack stereo and Motorcycle stereo of Middlebury benchmark show that the proposed method can remove fronto-parallel bias effectively, and produce continuous smooth surfaces.

  7. The output mode cleaner of GEO 600

    International Nuclear Information System (INIS)

    Prijatelj, M; Grote, H; Leong, J; Affeldt, C; Lück, H; Slutsky, J; Wittel, H; Strain, K; Danzmann, K; Degallaix, J; Hild, S

    2012-01-01

    The German-British interferometric gravitational wave detector GEO 600 is currently undergoing upgrades within the GEO-HF upgrade program. The goal of this program is to enhance the sensitivity of GEO 600, in particular at frequencies above 500 Hz. At these frequencies, the detector is limited by shot noise. An important element of the upgrade is the implementation of an output mode cleaner (OMC). This filtering cavity suppresses higher order spatial and temporal modes in the interferometer's output beam, thereby reducing the shot noise and enhancing sensitivity. Fully automated lock acquisition for the OMC was developed in order to ensure a high duty cycle of GEO 600. To maintain optimum sensitivity, the resonance condition of the OMC must be matched to the output beam from the interferometer. This requires continuous control of the resonance frequency of the OMC to the light, and alignment of the beam to the OMC. We describe the design and implementation of the OMC with special attention to the control techniques employed. We present results from the experience gained during the S6/VSR3 science run. Furthermore, we describe an upper limit measurement of the internal displacement noise of a piezoelectric actuator. (paper)

  8. Privacy-preserving matching of similar patients.

    Science.gov (United States)

    Vatsalan, Dinusha; Christen, Peter

    2016-02-01

    The identification of similar entities represented by records in different databases has drawn considerable attention in many application areas, including in the health domain. One important type of entity matching application that is vital for quality healthcare analytics is the identification of similar patients, known as similar patient matching. A key component of identifying similar records is the calculation of similarity of the values in attributes (fields) between these records. Due to increasing privacy and confidentiality concerns, using the actual attribute values of patient records to identify similar records across different organizations is becoming non-trivial because the attributes in such records often contain highly sensitive information such as personal and medical details of patients. Therefore, the matching needs to be based on masked (encoded) values while being effective and efficient to allow matching of large databases. Bloom filter encoding has widely been used as an efficient masking technique for privacy-preserving matching of string and categorical values. However, no work on Bloom filter-based masking of numerical data, such as integer (e.g. age), floating point (e.g. body mass index), and modulus (numbers wrap around upon reaching a certain value, e.g. date and time), which are commonly required in the health domain, has been presented in the literature. We propose a framework with novel methods for masking numerical data using Bloom filters, thereby facilitating the calculation of similarities between records. We conduct an empirical study on publicly available real-world datasets which shows that our framework provides efficient masking and achieves similar matching accuracy compared to the matching of actual unencoded patient records. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. A Comparison between Electrochemical Impedance Spectroscopy and Incremental Capacity-Differential Voltage as Li-ion Diagnostic Techniques to Identify and Quantify the Effects of Degradation Modes within Battery Management Systems

    Science.gov (United States)

    Pastor-Fernández, Carlos; Uddin, Kotub; Chouchelamane, Gael H.; Widanage, W. Dhammika; Marco, James

    2017-08-01

    Degradation of Lithium-ion batteries is a complex process that is caused by a variety of mechanisms. For simplicity, ageing mechanisms are often grouped into three degradation modes (DMs): conductivity loss (CL), loss of active material (LAM) and loss of lithium inventory (LLI). State of Health (SoH) is typically the parameter used by the Battery Management System (BMS) to quantify battery degradation based on the decrease in capacity and the increase in resistance. However, the definition of SoH within a BMS does not currently include an indication of the underlying DMs causing the degradation. Previous studies have analysed the effects of the DMs using incremental capacity and differential voltage (IC-DV) and electrochemical impedance spectroscopy (EIS). The aim of this study is to compare IC-DV and EIS on the same data set to evaluate if both techniques provide similar insights into the causes of battery degradation. For an experimental case of parallelized cells aged differently, the effects due to LAM and LLI were found to be the most pertinent, outlining that both techniques are correlated. This approach can be further implemented within a BMS to quantify the causes of battery ageing which would support battery lifetime control strategies and future battery designs.

  10. Privacy‐Preserving Friend Matching Protocol approach for Pre‐match in Social Networks

    DEFF Research Database (Denmark)

    Ople, Shubhangi S.; Deshmukh, Aaradhana A.; Mihovska, Albena Dimitrova

    2016-01-01

    Social services make the most use of the user profile matching to help the users to discover friends with similar social attributes (e.g. interests, location, age). However, there are many privacy concerns that prevent to enable this functionality. Privacy preserving encryption is not suitable...... for use in social networks due to its data sharing problems and information leakage. In this paper, we propose a novel framework for privacy–preserving profile matching. We implement both the client and server portion of the secure match and evaluate its performance network dataset. The results show...... that a secure match can achieve at least one order of accuracy and better computational performance than the techniques that use homomorphic encryption.It can handle and tackle new characteristics and an environment for a particular application in a mobile social network....

  11. Vein matching using artificial neural network in vein authentication systems

    Science.gov (United States)

    Noori Hoshyar, Azadeh; Sulaiman, Riza

    2011-10-01

    Personal identification technology as security systems is developing rapidly. Traditional authentication modes like key; password; card are not safe enough because they could be stolen or easily forgotten. Biometric as developed technology has been applied to a wide range of systems. According to different researchers, vein biometric is a good candidate among other biometric traits such as fingerprint, hand geometry, voice, DNA and etc for authentication systems. Vein authentication systems can be designed by different methodologies. All the methodologies consist of matching stage which is too important for final verification of the system. Neural Network is an effective methodology for matching and recognizing individuals in authentication systems. Therefore, this paper explains and implements the Neural Network methodology for finger vein authentication system. Neural Network is trained in Matlab to match the vein features of authentication system. The Network simulation shows the quality of matching as 95% which is a good performance for authentication system matching.

  12. DOE Matching Grant Program

    International Nuclear Information System (INIS)

    Tsoukalas, L.

    2002-01-01

    Funding used to support a portion of the Nuclear Engineering Educational Activities. Upgrade of teaching labs, student support to attend professional conferences, salary support for graduate students. The US Department of Energy (DOE) has funded Purdue University School of Nuclear Engineering during the period of five academic years covered in this report starting in the academic year 1996-97 and ending in the academic year 2000-2001. The total amount of funding for the grant received from DOE is $416K. In the 1990's, Nuclear Engineering Education in the US experienced a significant slow down. Student enrollment, research support, number of degrees at all levels (BS, MS, and PhD), number of accredited programs, University Research and Training Reactors, all went through a decline to alarmingly low levels. Several departments closed down, while some were amalgamated with other academic units (Mechanical Engineering, Chemical Engineering, etc). The School of Nuclear Engineering at Purdue University faced a major challenge when in the mid 90's our total undergraduate enrollment for the Sophomore, Junior and Senior Years dropped in the low 30's. The DOE Matching Grant program greatly strengthened Purdue's commitment to the Nuclear Engineering discipline and has helped to dramatically improve our undergraduate and graduate enrollment, attract new faculty and raise the School of Nuclear Engineering status within the University and in the National scene (our undergraduate enrollment has actually tripled and stands at an all time high of over 90 students; total enrollment currently exceeds 110 students). In this final technical report we outline and summarize how the grant was expended at Purdue University

  13. Bridging Database Applications and Declarative Similarity Matching

    OpenAIRE

    Andrade Ribeiro, Leonardo; Schneider, Natália Cristina; de Souza Inácio, Andrei; Wagner, Harley Michel; von Wangenheim, Aldo

    2017-01-01

    Effective manipulation of string data is of fundamental importance to modern database applications. Very often, textual inconsistencies render equality comparisons meaningless and strings have to be matched in terms of their similarity. Previous work has proposed techniques to express similarity operations using declarative SQL statements. However, the non-trivial issue of embedding similarity support into object-oriented applications has received little attention. Particularly, declarative s...

  14. Matching theory for wireless networks

    CERN Document Server

    Han, Zhu; Saad, Walid

    2017-01-01

    This book provides the fundamental knowledge of the classical matching theory problems. It builds up the bridge between the matching theory and the 5G wireless communication resource allocation problems. The potentials and challenges of implementing the semi-distributive matching theory framework into the wireless resource allocations are analyzed both theoretically and through implementation examples. Academics, researchers, engineers, and so on, who are interested in efficient distributive wireless resource allocation solutions, will find this book to be an exceptional resource. .

  15. Matching Games with Additive Externalities

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal

    2012-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas...... fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. In this framework, we analyze many-to-many and one-to-one matchings under neutral...

  16. Edge-localized mode avoidance and pedestal structure in I-mode plasmasa)

    Science.gov (United States)

    Walk, J. R.; Hughes, J. W.; Hubbard, A. E.; Terry, J. L.; Whyte, D. G.; White, A. E.; Baek, S. G.; Reinke, M. L.; Theiler, C.; Churchill, R. M.; Rice, J. E.; Snyder, P. B.; Osborne, T.; Dominguez, A.; Cziegler, I.

    2014-05-01

    I-mode is a high-performance tokamak regime characterized by the formation of a temperature pedestal and enhanced energy confinement, without an accompanying density pedestal or drop in particle and impurity transport. I-mode operation appears to have naturally occurring suppression of large Edge-Localized Modes (ELMs) in addition to its highly favorable scalings of pedestal structure and overall performance. Extensive study of the ELMy H-mode has led to the development of the EPED model, which utilizes calculations of coupled peeling-ballooning MHD modes and kinetic-ballooning mode (KBM) stability limits to predict the pedestal structure preceding an ELM crash. We apply similar tools to the structure and ELM stability of I-mode pedestals. Analysis of I-mode discharges prepared with high-resolution pedestal data from the most recent C-Mod campaign reveals favorable pedestal scalings for extrapolation to large machines—pedestal temperature scales strongly with power per particle Pnet/n ¯e, and likewise pedestal pressure scales as the net heating power (consistent with weak degradation of confinement with heating power). Matched discharges in current, field, and shaping demonstrate the decoupling of energy and particle transport in I-mode, increasing fueling to span nearly a factor of two in density while maintaining matched temperature pedestals with consistent levels of Pnet/n ¯e. This is consistent with targets for increased performance in I-mode, elevating pedestal βp and global performance with matched increases in density and heating power. MHD calculations using the ELITE code indicate that I-mode pedestals are strongly stable to edge peeling-ballooning instabilities. Likewise, numerical modeling of the KBM turbulence onset, as well as scalings of the pedestal width with poloidal beta, indicates that I-mode pedestals are not limited by KBM turbulence—both features identified with the trigger for large ELMs, consistent with the observed suppression of

  17. Investigations on Shaped Mirror Systems in Quasi-Optical Mode Converters Based on Irradiance Moments Method

    Directory of Open Access Journals (Sweden)

    Hai Wang

    2016-01-01

    Full Text Available A method of transforming high-order Gaussian beams (GBs mode into circular symmetry fundamental Gaussian beam (FGB mode with arbitrary waist size is presented using irradiance moments method in quasi-optical (QO mode converters. The double shaped mirrors correcting amplitude and phase simultaneously are generated by a single incidence irradiance sampling data and known ideal output FGB taking advantage of linear moment matching technique and Fresnel diffraction theory, which can be applied to a wide frequency range especially significant for terahertz band. The numerical coding procedure of creating double correcting mirrors and its fast convergence speed are discussed at 325 GHz. Numerical and experimental comparisons reveal the conclusion that enhancing surface precision and increasing moments order can improve main lobe levels.

  18. Statistical methods for history matching

    DEFF Research Database (Denmark)

    Johansen, Kent

    Denne afhandling beskriver statistiske metoder til history matching af olieproduktion. History matching er en vigtig del af driften af et oliefelt og er ofte forbundet med problemer relateret til kompleksiteten af reservoiret og selve størrelsen af reservoirsimuleringsmodellen. Begrebet history m...

  19. Matching score based face recognition

    NARCIS (Netherlands)

    Boom, B.J.; Beumer, G.M.; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

    2006-01-01

    Accurate face registration is of vital importance to the performance of a face recognition algorithm. We propose a new method: matching score based face registration, which searches for optimal alignment by maximizing the matching score output of a classifier as a function of the different

  20. Efficient line matching with homography

    Science.gov (United States)

    Shen, Yan; Dai, Yuxing; Zhu, Zhiliang

    2018-03-01

    In this paper, we propose a novel approach to line matching based on homography. The basic idea is to use cheaply obtainable matched points to boost the similarity between two images. Two types of homography method, which are estimated by direct linear transformation, transform images and extract their similar parts, laying a foundation for the use of optical flow tracking. The merit of the similarity is that rapid matching can be achieved by regionalizing line segments and local searching. For multiple homography estimation that can perform better than one global homography, we introduced the rank-one modification method of singular value decomposition to reduce the computation cost. The proposed approach results in point-to-point matches, which can be utilized with state-of-the-art point-match-based structures from motion (SfM) frameworks seamlessly. The outstanding performance and feasible robustness of our approach are demonstrated in this paper.

  1. Table tennis match analysis: a review.

    Science.gov (United States)

    Fuchs, Michael; Liu, Ruizhi; Malagoli Lanzoni, Ivan; Munivrana, Goran; Straub, Gunter; Tamaki, Sho; Yoshida, Kazuto; Zhang, Hui; Lames, Martin

    2018-03-15

    In table tennis, many different approaches to scientific founded match analysis have been developed since the first ones in the 1960s. The aim of this paper is to give a review on some of the most acknowledged methods of match analysis in table tennis. The first chapter presents a historical overview of match analysis from all over the world. The second part reviews different approaches to match analysis in more detail, using the performance analysis classification of theoretical and practical performance analysis. The review includes the most actual theoretical performance analysis techniques in table tennis: performance indices, simulative approaches, momentum analysis, footwork analysis, and finally an approach which uses top expert knowledge for a comprehensive technical-tactical analysis. In the section of practical performance analysis, the paper presents two "best practice" examples describing performance analysis procedures of the two most successful countries of the last Olympics: China and Japan. The paper ends with a summary on the impact of the different approaches and gives an outlook on promising new developments.

  2. Mode control and mode conversion in nonlinear aluminum nitride waveguides.

    Science.gov (United States)

    Stegmaier, Matthias; Pernice, Wolfram H P

    2013-11-04

    While single-mode waveguides are commonly used in integrated photonic circuits, emerging applications in nonlinear and quantum optics rely fundamentally on interactions between modes of different order. Here we propose several methods to evaluate the modal composition of both externally and device-internally excited guided waves and discuss a technique for efficient excitation of arbitrary modes. The applicability of these methods is verified in photonic circuits based on aluminum nitride. We control modal excitation through suitably engineered grating couplers and are able to perform a detailed study of waveguide-internal second harmonic generation. Efficient and broadband power conversion between orthogonal polarizations is realized within an asymmetric directional coupler to demonstrate selective excitation of arbitrary higher-order modes. Our approach holds promise for applications in nonlinear optics and frequency up/down-mixing in a chipscale framework.

  3. A Bloch mode expansion approach for analyzing quasi-normal modes in open nanophotonic structures

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

    2014-01-01

    We present a new method for determining quasi-normal modes in open nanophotonic structures using a modal ex- pansion technique. The outgoing wave boundary condition of the quasi-normal modes is satisfied automatically without absorbing boundaries, representing a significant advantage compared...... to conventional techniques. The quasi-normal modes are determined by constructing a cavity roundtrip matrix and iterating the complex mode wavelength towards a unity eigenvalue. We demonstrate the method by deter- mining quasi-normal modes of cavities in two-dimensional photonic crystals side-coupled to W1...

  4. Approximate Matching of Hierarchial Data

    DEFF Research Database (Denmark)

    Augsten, Nikolaus

    The goal of this thesis is to design, develop, and evaluate new methods for the approximate matching of hierarchical data represented as labeled trees. In approximate matching scenarios two items should be matched if they are similar. Computing the similarity between labeled trees is hard...... formally proof that the pq-gram index can be incrementally updated based on the log of edit operations without reconstructing intermediate tree versions. The incremental update is independent of the data size and scales to a large number of changes in the data. We introduce windowed pq...... as in addition to the data values also the structure must be considered. A well-known measure for comparing trees is the tree edit distance. It is computationally expensive and leads to a prohibitively high run time. Our solution for the approximate matching of hierarchical data are pq-grams. The pq...

  5. Multi-track Map Matching

    OpenAIRE

    Javanmard, Adel; Haridasan, Maya; Zhang, Li

    2012-01-01

    We study algorithms for matching user tracks, consisting of time-ordered location points, to paths in the road network. Previous work has focused on the scenario where the location data is linearly ordered and consists of fairly dense and regular samples. In this work, we consider the \\emph{multi-track map matching}, where the location data comes from different trips on the same route, each with very sparse samples. This captures the realistic scenario where users repeatedly travel on regular...

  6. Trapped modes in an infinite or semi-infinite tube with a local enlargement.

    Science.gov (United States)

    Li, Wei-Sha; Zou, Jiaqi; Lee, Kang Yong; Li, Xian-Fang

    2016-09-01

    Trapped modes in a hard cylindrical tube with a local axisymmetric enlargement or bulge and filled with a uniform acoustic medium is studied. The governing Helmholtz equation in the cylindrical coordinate system is employed to deal with this problem through the domain decomposition method and matching technique. The trapped modes and the corresponding frequencies less than the threshold frequency or cut-off frequency are derived. It is found that in addition to the fundamental mode, the second- and higher-order trapped modes exist and depend on the geometry parameters of the local bulge. The effects of the bulge radius and width on the frequencies are discussed. The local bulge leads to a decrease of the frequencies and the corresponding vibration mode is localized near the bulge. A multimodal analysis is made and frequency band gap of generalized trapped modes is also studied. A frequency band gap depends on the radius of a bulge and is independent of its width. The obtained results can be extended to analyze bound states in quantum wires. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Discrete-time nonlinear sliding mode controller

    African Journals Online (AJOL)

    user

    desired trajectory. In Bandhyopadhyay and Deepak (2009), nonlinear sliding surface is created for varying the damping factor for improving the performance of the multi-input and multi-output linear systems with matched conditions. Some of the concepts and theoretical advances of continuous time sliding mode control are ...

  8. Newer nonconventional modes of mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Preet Mohinder Singh

    2014-01-01

    Full Text Available The conventional modes of ventilation suffer many limitations. Although they are popularly used and are well-understood, often they fail to match the patient-based requirements. Over the years, many small modifications in ventilators have been incorporated to improve patient outcome. The ventilators of newer generation respond to patient′s demands by additional feedback systems. In this review, we discuss the popular newer modes of ventilation that have been accepted in to clinical practice. Various intensive care units over the world have found these modes to improve patient ventilator synchrony, decrease ventilator days and improve patient safety. The various modes discusses in this review are: Dual control modes (volume assured pressure support, volume support, Adaptive support ventilation, proportional assist ventilation, mandatory minute ventilation, Bi-level airway pressure release ventilation, (BiPAP, neurally adjusted ventilatory assist and NeoGanesh. Their working principles with their advantages and clinical limitations are discussed in brief.

  9. Collinear phase matching for second harmonic generation using conoscopic interferometry

    Science.gov (United States)

    De, A.; Puri, A.

    2010-04-01

    The problem of finding phase-matching directions in noncentrosymmetric biaxial crystals is simplified here by the use of Conoscopic interferometry. Based on vector relations for wave propagation in birefringent media and solutions to phase-matching equations, we show that phase matching directions can be located on the conoscopic interferograms and that fringe numbers for dark-isochromes can be used as a guide to find phase-matching directions for a biaxial crystal. This technique can be generalized and extended to any anisotropic crystal. We have demonstrated this method for the particular case of a biaxial KTiOPO4 crystal, where it is found to be particularly suitable for finding the optimum-phase-matching directions.

  10. Forest Roadidentification and Extractionof Through Advanced Log Matching Techniques

    Science.gov (United States)

    Zhang, W.; Hu, B.; Quist, L.

    2017-10-01

    A novel algorithm for forest road identification and extraction was developed. The algorithm utilized Laplacian of Gaussian (LoG) filter and slope calculation on high resolution multispectral imagery and LiDAR data respectively to extract both primary road and secondary road segments in the forest area. The proposed method used road shape feature to extract the road segments, which have been further processed as objects with orientation preserved. The road network was generated after post processing with tensor voting. The proposed method was tested on Hearst forest, located in central Ontario, Canada. Based on visual examination against manually digitized roads, the majority of roads from the test area have been identified and extracted from the process.

  11. Wing and Engine Sizing by Using the Matching Plot Technique

    Directory of Open Access Journals (Sweden)

    Glīzde Nikolajs

    2017-12-01

    Full Text Available The research focuses on the development of an Unmanned Aircraft System. For design purposes, a rather new design method called Systems Engineering Approach is used. Development of the whole system takes much time and effort. This paper contains a concise description of the research on the preliminary development phase of Unmanned Aircraft System air vehicle. The method was first introduced by NASA and later developed by authors of books on aircraft design used for information purposes for design and are mentioned in references. The obtained results are rather realistic and promising for further design process. The method is simple and understandable, and it should be used more often to make it more steady and reliable.

  12. FOREST ROADIDENTIFICATION AND EXTRACTIONOF THROUGH ADVANCED LOG MATCHING TECHNIQUES

    Directory of Open Access Journals (Sweden)

    W. Zhang

    2017-10-01

    Full Text Available A novel algorithm for forest road identification and extraction was developed. The algorithm utilized Laplacian of Gaussian (LoG filter and slope calculation on high resolution multispectral imagery and LiDAR data respectively to extract both primary road and secondary road segments in the forest area. The proposed method used road shape feature to extract the road segments, which have been further processed as objects with orientation preserved. The road network was generated after post processing with tensor voting. The proposed method was tested on Hearst forest, located in central Ontario, Canada. Based on visual examination against manually digitized roads, the majority of roads from the test area have been identified and extracted from the process.

  13. A dimensionality reduction technique for 2D scattering problems in photonics

    Science.gov (United States)

    Alyona Ivanova, O. V.; Stoffer, Remco; Hammer, Manfred

    2010-03-01

    This paper describes a simulation method for 2D frequency domain scattering problems in photonics. The technique reduces the spatial dimensionality of the problem by means of global, continuous mode expansion combined with a variational formalism; the resulting equations are solved using a finite element method. Transparent influx boundary conditions and perfectly matched layers are employed at the computational window boundaries. Numerical examples validate the method.

  14. An Implementation of the Frequency Matching Method

    DEFF Research Database (Denmark)

    Lange, Katrine; Frydendall, Jan; Hansen, Thomas Mejer

    During the last decade multiple-point statistics has become in-creasingly popular as a tool for incorporating complex prior infor-mation when solving inverse problems in geosciences. A variety of methods have been proposed but often the implementation of these is not straightforward. One of these......During the last decade multiple-point statistics has become in-creasingly popular as a tool for incorporating complex prior infor-mation when solving inverse problems in geosciences. A variety of methods have been proposed but often the implementation of these is not straightforward. One...... of these methods is the recently proposed Frequency Matching method to compute the maximum a posteriori model of an inverse problem where multiple-point statistics, learned from a training image, is used to formulate a closed form expression for an a priori probability density function. This paper discusses...... aspects of the implementation of the Fre-quency Matching method and the techniques adopted to make it com-putationally feasible also for large-scale inverse problems. The source code is publicly available at GitHub and this paper also provides an example of how to apply the Frequency Matching method...

  15. Development of a hybrid mode linear transformer driver stage

    Directory of Open Access Journals (Sweden)

    Le Zhang

    2018-02-01

    Full Text Available At present, the mainstream technologies of primary power sources of large pulse power devices adopt Marx or linear transformer driver (LTD designs. Based on the analysis of the characteristics of these two types of circuit topologies, the concept of a hybrid mode LTD stage based on Marx branches is proposed. The analysis shows that the hybrid mode LTD stage can realize the following goals: (a to reduce the energy and power handled by the basic components (switch and capacitor to lengthen their lifetime; (b to reduce the requirements of the multipath synchronous trigger system; and (c to improve the maintainability of the LTD stage by using independent Marx generators instead of “traditional LTD bricks.” To verify the technique, a hybrid mode LTD stage consisting of 50 branches (four-stage compact Marx generators was designed, manufactured and tested. The stage has a radius of about 3.3 m and a height of 0.6 m. The single Marx circuit’s load current is about 21 kA, with a rise time of ∼90  ns (10%–90%, under the conditions of capacitors charged to ±40  kV and a 6.9  Ω matched load. The whole stage’s load current is ∼1  MA, with a rise time of ∼112  ns (10%–90%, when the capacitors are charged to ±45  kV and the matched load is 0.14  Ω.

  16. Reduction of Edge-Localized Mode Intensity Using High-Repetition-Rate Pellet Injection in Tokamak H-Mode Plasmas

    Science.gov (United States)

    Baylor, L. R.; Commaux, N.; Jernigan, T. C.; Brooks, N. H.; Combs, S. K.; Evans, T. E.; Fenstermacher, M. E.; Isler, R. C.; Lasnier, C. J.; Meitner, S. J.; Moyer, R. A.; Osborne, T. H.; Parks, P. B.; Snyder, P. B.; Strait, E. J.; Unterberg, E. A.; Loarte, A.

    2013-06-01

    High repetition rate injection of deuterium pellets from the low-field side (LFS) of the DIII-D tokamak is shown to trigger high-frequency edge-localized modes (ELMs) at up to 12× the low natural ELM frequency in H-mode deuterium plasmas designed to match the ITER baseline configuration in shape, normalized beta, and input power just above the H-mode threshold. The pellet size, velocity, and injection location were chosen to limit penetration to the outer 10% of the plasma. The resulting perturbations to the plasma density and energy confinement time are thus minimal (pellet injection excites a localized high-n instability. Triggered ELMs produce up to 12× lower energy and particle fluxes to the divertor, and result in a strong decrease in plasma core impurity density. These results show for the first time that shallow, LFS pellet injection can dramatically accelerate the ELM cycle and reduce ELM energy fluxes on plasma facing components, and is a viable technique for real-time control of ELMs in ITER.

  17. The Kent Face Matching Test.

    Science.gov (United States)

    Fysh, Matthew C; Bindemann, Markus

    2018-05-01

    This study presents the Kent Face Matching Test (KFMT), which comprises 200 same-identity and 20 different-identity pairs of unfamiliar faces. Each face pair consists of a photograph from a student ID card and a high-quality portrait that was taken at least three months later. The test is designed to complement existing resources for face-matching research, by providing a more ecologically valid stimulus set that captures the natural variability that can arise in a person's appearance over time. Two experiments are presented to demonstrate that the KFMT provides a challenging measure of face matching but correlates with established tests. Experiment 1 compares a short version of this test with the optimized Glasgow Face Matching Test (GFMT). In Experiment 2, a longer version of the KFMT, with infrequent identity mismatches, is correlated with performance on the Cambridge Face Memory Test (CFMT) and the Cambridge Face Perception Test (CFPT). The KFMT is freely available for use in face-matching research. © 2017 The British Psychological Society.

  18. Biaxial compression test technique

    Science.gov (United States)

    Hansard, E. T.

    1975-01-01

    Fixture and technique have been developed for predicting behavior of stiffened skin panels under biaxial compressive loading. Tester can load test panel independently in longitudinal and transverse directions. Data can also be obtained in combined mode.

  19. History Matching in Parallel Computational Environments

    Energy Technology Data Exchange (ETDEWEB)

    Steven Bryant; Sanjay Srinivasan; Alvaro Barrera; Sharad Yadav

    2005-10-01

    some specific simulators. Therefore a robust technique to evaluate a covariance matrix, which is analogous to ''Hessian matrix'', from a set of equi-probable realizations has also been developed. This technique is easy to implement and provides the domains, which could be intuitively justified. Since the domain delineation process yields zones that are least correlated with each other, each r{sub D} parameter can be optimized independently and simultaneously using individual nodes of a cluster of computers. Further least correlation criteria help in retaining the simplicity of 1-D optimization during the history matching. Upon convergence, the perturbed regions are put together and the history match is verified. The proposed approach results in a set of independent tasks of equal magnitude and thus is particularly suited for distributed computing. The methodology has been successfully tested on various synthetic cases.

  20. Design of on-chip data sparsification for a mixed-mode MAPS device

    CERN Document Server

    Gabrielli, Alessandro

    2007-01-01

    The device described in the paper is built up of a bidimensional matrix of Monolithic Active Pixel Sensor (MAPS) and an off-pixel digital readout sparsification circuit. The readout logic is based on std-cells and implements an optimised technique aimed at overcoming the readout speed limit of future large-matrix pixel detectors for particle tracking, by matching the requirements of future HEP experiments. In particular, the readout architecture extends the flexibility of the MAPS devices to be also used in first level triggers in vertex detectors. The work extends a first version of a mixed mode device submitted on Nov. 2006 and implemented with the same technology.

  1. The Statistical Power of the Cluster Randomized Block Design with Matched Pairs--A Simulation Study

    Science.gov (United States)

    Dong, Nianbo; Lipsey, Mark

    2010-01-01

    This study uses simulation techniques to examine the statistical power of the group- randomized design and the matched-pair (MP) randomized block design under various parameter combinations. Both nearest neighbor matching and random matching are used for the MP design. The power of each design for any parameter combination was calculated from…

  2. Influence of ensemble geostatistics on production history matching and prediction at new wells

    NARCIS (Netherlands)

    Peters, E.; Leeuwenburgh, O.; Hanea, R.G.

    2008-01-01

    Automatic history matching techniques such as the Ensemble Kalman Filter (EnKF) have been shown to provide reliable results for matching and prediction at existing wells. It is much less clear if the prediction outside of existing wells improves as a result of history matching. The amount of

  3. Influence of a Prolonged Tennis Match Play on Serve Biomechanics.

    Directory of Open Access Journals (Sweden)

    Caroline Martin

    Full Text Available The aim of this study was to quantify kinematic, kinetic and performance changes that occur in the serve throughout a prolonged tennis match play. Serves of eight male advanced tennis players were recorded with a motion capture system before, at mid-match, and after a 3-hour tennis match. Before and after each match, electromyographic data of 8 upper limb muscles obtained during isometric maximal voluntary contraction were compared to determine the presence of muscular fatigue. Vertical ground reaction forces, rating of perceived exertion, ball speed, and ball impact height were measured. Kinematic and upper limb kinetic variables were computed. The results show decrease in mean power frequency values for several upper limb muscles that is an indicator of local muscular fatigue. Decreases in serve ball speed, ball impact height, maximal angular velocities and an increase in rating of perceived exertion were also observed between the beginning and the end of the match. With fatigue, the majority of the upper limb joint kinetics decreases at the end of the match. No change in timing of maximal angular velocities was observed between the beginning and the end of the match. A prolonged tennis match play may induce fatigue in upper limb muscles, which decrease performance and cause changes in serve maximal angular velocities and joint kinetics. The consistency in timing of maximal angular velocities suggests that advanced tennis players are able to maintain the temporal pattern of their serve technique, in spite of the muscular fatigue development.

  4. Poor textural image tie point matching via graph theory

    Science.gov (United States)

    Yuan, Xiuxiao; Chen, Shiyu; Yuan, Wei; Cai, Yang

    2017-07-01

    Feature matching aims to find corresponding points to serve as tie points between images. Robust matching is still a challenging task when input images are characterized by low contrast or contain repetitive patterns, occlusions, or homogeneous textures. In this paper, a novel feature matching algorithm based on graph theory is proposed. This algorithm integrates both geometric and radiometric constraints into an edge-weighted (EW) affinity tensor. Tie points are then obtained by high-order graph matching. Four pairs of poor textural images covering forests, deserts, bare lands, and urban areas are tested. For comparison, three state-of-the-art matching techniques, namely, scale-invariant feature transform (SIFT), speeded up robust features (SURF), and features from accelerated segment test (FAST), are also used. The experimental results show that the matching recall obtained by SIFT, SURF, and FAST varies from 0 to 35% in different types of poor textures. However, through the integration of both geometry and radiometry and the EW strategy, the recall obtained by the proposed algorithm is better than 50% in all four image pairs. The better matching recall improves the number of correct matches, dispersion, and positional accuracy.

  5. Viscoelastic modes in chiral liquid crystals

    Indian Academy of Sciences (India)

    Viscoelastic properties of liquid crystals are very important for applications like display technology. However, there are not many direct techniques to study them. In this review, we describe our studies on the viscoelastic modes of some chiral liquid crystals using dynamic light scattering. We discuss viscoelastic modes ...

  6. Mix-and-match holography

    KAUST Repository

    Peng, Yifan

    2017-11-22

    Computational caustics and light steering displays offer a wide range of interesting applications, ranging from art works and architectural installations to energy efficient HDR projection. In this work we expand on this concept by encoding several target images into pairs of front and rear phase-distorting surfaces. Different target holograms can be decoded by mixing and matching different front and rear surfaces under specific geometric alignments. Our approach, which we call mix-and-match holography, is made possible by moving from a refractive caustic image formation process to a diffractive, holographic one. This provides the extra bandwidth that is required to multiplex several images into pairing surfaces.

  7. An Implementation of Bigraph Matching

    DEFF Research Database (Denmark)

    Glenstrup, Arne John; Damgaard, Troels Christoffer; Birkedal, Lars

    We describe a provably sound and complete matching algorithm for bigraphical reactive systems. The algorithm has been implemented in our BPL Tool, a first implementation of bigraphical reactive systems. We describe the tool and present a concrete example of how it can be used to simulate a model ...... of a mobile phone system in a bigraphical representation of the polyadic π calculus.......We describe a provably sound and complete matching algorithm for bigraphical reactive systems. The algorithm has been implemented in our BPL Tool, a first implementation of bigraphical reactive systems. We describe the tool and present a concrete example of how it can be used to simulate a model...

  8. Renormalized modes in cuprate superconductors

    Science.gov (United States)

    Gupta, Anushri; Kumari, Anita; Verma, Sanjeev K.; Indu, B. D.

    2018-04-01

    The renormalized mode frequencies are obtained with the help of quantum dynamical approach of many body phonon Green's function technique via a general Hamiltonian (excluding BCS Hamiltonian) including the effects of phonons and electrons, anharmonicities and electron-phonon interactions. The numerical estimates have been carried out to study the renormalized mode frequency of high temperature cuprate superconductor (HTS) YBa2Cu3O7-δ using modified Born-Mayer-Huggins interaction potential (MBMHP) best applicable to study the dynamical properties of all HTS.

  9. Image Segmentation, Registration, Compression, and Matching

    Science.gov (United States)

    Yadegar, Jacob; Wei, Hai; Yadegar, Joseph; Ray, Nilanjan; Zabuawala, Sakina

    2011-01-01

    A novel computational framework was developed of a 2D affine invariant matching exploiting a parameter space. Named as affine invariant parameter space (AIPS), the technique can be applied to many image-processing and computer-vision problems, including image registration, template matching, and object tracking from image sequence. The AIPS is formed by the parameters in an affine combination of a set of feature points in the image plane. In cases where the entire image can be assumed to have undergone a single affine transformation, the new AIPS match metric and matching framework becomes very effective (compared with the state-of-the-art methods at the time of this reporting). No knowledge about scaling or any other transformation parameters need to be known a priori to apply the AIPS framework. An automated suite of software tools has been created to provide accurate image segmentation (for data cleaning) and high-quality 2D image and 3D surface registration (for fusing multi-resolution terrain, image, and map data). These tools are capable of supporting existing GIS toolkits already in the marketplace, and will also be usable in a stand-alone fashion. The toolkit applies novel algorithmic approaches for image segmentation, feature extraction, and registration of 2D imagery and 3D surface data, which supports first-pass, batched, fully automatic feature extraction (for segmentation), and registration. A hierarchical and adaptive approach is taken for achieving automatic feature extraction, segmentation, and registration. Surface registration is the process of aligning two (or more) data sets to a common coordinate system, during which the transformation between their different coordinate systems is determined. Also developed here are a novel, volumetric surface modeling and compression technique that provide both quality-guaranteed mesh surface approximations and compaction of the model sizes by efficiently coding the geometry and connectivity

  10. H-mode physics

    International Nuclear Information System (INIS)

    Itoh, Sanae.

    1991-06-01

    After the discovery of the H-mode in ASDEX ( a tokamak in Germany ) the transition between the L-mode ( Low confinement mode ) and H-mode ( High confinement mode ) has been observed in many tokamaks in the world. The H-mode has made a breakthrough in improving the plasma parameters and has been recognized to be a universal phenomena. Since its discovery, the extensive studies both in experiments and in theory have been made. The research on H-mode has been casting new problems of an anomalous transport across the magnetic surface. This series of lectures will provide a brief review of experiments for explaining H-mode and a model theory of H-mode transition based on the electric field bifurcation. If the time is available, a new theoretical model of the temporal evolution of the H-mode will be given. (author)

  11. Within-Cluster and Across-Cluster Matching with Observational Multilevel Data

    Science.gov (United States)

    Kim, Jee-Seon; Steiner, Peter M.; Hall, Courtney; Thoemmes, Felix

    2013-01-01

    When randomized experiments cannot be conducted in practice, propensity score (PS) techniques for matching treated and control units are frequently used for estimating causal treatment effects from observational data. Despite the popularity of PS techniques, they are not yet well studied for matching multilevel data where selection into treatment…

  12. Optimized noninvasive monitoring of thermal changes on digital B-mode renal sonography during revascularization therapy.

    Science.gov (United States)

    Abolhassani, Mohammad D; Tavakoli, Vahid; Sahba, Nima

    2009-11-01

    Noninvasive real-time thermal change monitoring of human internal organs can play a critical role in diagnosis and treatment of many disorders, including reperfusion of renal arteries during anticoagulation therapy. This article focuses on tissue temperature detection using ultrasound velocity changes in different structures and their related speckle shift from their primary locations on high-quality B-mode digital sonography. We evaluated different speckle-tracking techniques and optimized them using appropriate motion estimation methods to determine the best algorithm and parameters. Performing thermal detection methods on simulated phantoms showed a good correlation between speckle shifts and the ground truth temperature. For the simulated images, average thermal error was 0.5 degrees C with an SD of 0.5 degrees C, where lower errors can be obtained in noiseless (motionless) data. The proposed technique was evaluated on real in vivo cases during surgical occlusion and reopening of the renal segmental artery and showed the potential of the algorithm for observation of internal organ changes using only digital ultrasound systems for diagnosis and therapy. The adaptive Rood pattern search proved to be the best block-matching technique, whereas the multiresolution Horn-Schunck technique was the best gradient optical flow method. The extracted thermal change during in vivo revascularization therapy is promising. In addition, we present an evaluation of several block-matching and optical flow motion estimation techniques.

  13. Matching of equivalent field regions

    DEFF Research Database (Denmark)

    Appel-Hansen, Jørgen; Rengarajan, S.B.

    2005-01-01

    In aperture problems, integral equations for equivalent currents are often found by enforcing matching of equivalent fields. The enforcement is made in the aperture surface region adjoining the two volumes on each side of the aperture. In the case of an aperture in a planar perfectly conducting...... screen, having the same homogeneous medium on both sides and an impressed current on one aide, an alternative procedure is relevant. We make use of the fact that in the aperture the tangential component of the magnetic field due to the induced currents in the screen is zero. The use of such a procedure...... shows that equivalent currents can be found by a consideration of only one of the two volumes into which the aperture plane divides the space. Furthermore, from a consideration of an automatic matching at the aperture, additional information about tangential as well as normal field components...

  14. Role model and prototype matching

    DEFF Research Database (Denmark)

    Lykkegaard, Eva; Ulriksen, Lars

    2016-01-01

    Previous research has found that young people’s prototypes of science students and scientists affect their inclination to choose tertiary STEM programs (Science, Technology, Engineering and Mathematics). Consequently, many recruitment initiatives include role models to challenge these prototypes......’ meetings with the role models affected their thoughts concerning STEM students and attending university. The regular self-to-prototype matching process was shown in real-life role-models meetings to be extended to a more complex three-way matching process between students’ self-perceptions, prototype...... images and situation-specific conceptions of role models. Furthermore, the study underlined the positive effect of prolonged role-model contact, the importance of using several role models and that traditional school subjects catered more resistant prototype images than unfamiliar ones did...

  15. University Reactor Matching Grants Program

    International Nuclear Information System (INIS)

    John Valentine; Farzad Rahnema; Said Abdel-Khalik

    2003-01-01

    During the 2002 Fiscal year, funds from the DOE matching grant program, along with matching funds from the industrial sponsors, have been used to support research in the area of thermal-hydraulics. Both experimental and numerical research projects have been performed. Experimental research focused on two areas: (1) Identification of the root cause mechanism for axial offset anomaly in pressurized water reactors under prototypical reactor conditions, and (2) Fluid dynamic aspects of thin liquid film protection schemes for inertial fusion reactor chambers. Numerical research focused on two areas: (1) Multi-fluid modeling of both two-phase and two-component flows for steam conditioning and mist cooling applications, and (2) Modeling of bounded Rayleigh-Taylor instability with interfacial mass transfer and fluid injection through a porous wall simulating the ''wetted wall'' protection scheme in inertial fusion reactor chambers. Details of activities in these areas are given

  16. Fractured reservoir history matching improved based on artificial intelligent

    Directory of Open Access Journals (Sweden)

    Sayyed Hadi Riazi

    2016-12-01

    Full Text Available In this paper, a new robust approach based on Least Square Support Vector Machine (LSSVM as a proxy model is used for an automatic fractured reservoir history matching. The proxy model is made to model the history match objective function (mismatch values based on the history data of the field. This model is then used to minimize the objective function through Particle Swarm Optimization (PSO and Imperialist Competitive Algorithm (ICA. In automatic history matching, sensitive analysis is often performed on full simulation model. In this work, to get new range of the uncertain parameters (matching parameters in which the objective function has a minimum value, sensitivity analysis is also performed on the proxy model. By applying the modified ranges to the optimization methods, optimization of the objective function will be faster and outputs of the optimization methods (matching parameters are produced in less time and with high precision. This procedure leads to matching of history of the field in which a set of reservoir parameters is used. The final sets of parameters are then applied for the full simulation model to validate the technique. The obtained results show that the present procedure in this work is effective for history matching process due to its robust dependability and fast convergence speed. Due to high speed and need for small data sets, LSSVM is the best tool to build a proxy model. Also the comparison of PSO and ICA shows that PSO is less time-consuming and more effective.

  17. A Practical Test Method for Mode I Fracture Toughness of Adhesive Joints with Dissimilar Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Boeman, R.G.; Erdman, D.L.; Klett, L.B.; Lomax, R.D.

    1999-09-27

    A practical test method for determining the mode I fracture toughness of adhesive joints with dissimilar substrates will be discussed. The test method is based on the familiar Double Cantilever Beam (DCB) specimen geometry, but overcomes limitations in existing techniques that preclude their use when testing joints with dissimilar substrates. The test method is applicable to adhesive joints where the two bonded substrates have different flexural rigidities due to geometric and/or material considerations. Two specific features discussed are the use of backing beams to prevent substrate damage and a compliance matching scheme to achieve symmetric loading conditions. The procedure is demonstrated on a modified DCB specimen comprised of SRIM composite and thin-section, e-coat steel substrates bonded with an epoxy adhesive. Results indicate that the test method provides a practical means of characterizing the mode I fracture toughness of joints with dissimilar substrates.

  18. Matching conditions in relativistic astrophysics

    OpenAIRE

    Quevedo, Hernando

    2012-01-01

    We present an exact electrovacuum solution of Einstein-Maxwell equations with infinite sets of multipole moments which can be used to describe the exterior gravitational field of a rotating charged mass distribution. We show that in the special case of a slowly rotating and slightly deformed body, the exterior solution can be matched to an interior solution belonging to the Hartle-Thorne family of approximate solutions. To search for exact interior solutions, we propose to use the derivatives...

  19. Impedance-matched Marx generators

    Directory of Open Access Journals (Sweden)

    W. A. Stygar

    2017-04-01

    Full Text Available We have conceived a new class of prime-power sources for pulsed-power accelerators: impedance-matched Marx generators (IMGs. The fundamental building block of an IMG is a brick, which consists of two capacitors connected electrically in series with a single switch. An IMG comprises a single stage or several stages distributed axially and connected in series. Each stage is powered by a single brick or several bricks distributed azimuthally within the stage and connected in parallel. The stages of a multistage IMG drive an impedance-matched coaxial transmission line with a conical center conductor. When the stages are triggered sequentially to launch a coherent traveling wave along the coaxial line, the IMG achieves electromagnetic-power amplification by triggered emission of radiation. Hence a multistage IMG is a pulsed-power analogue of a laser. To illustrate the IMG approach to prime power, we have developed conceptual designs of two ten-stage IMGs with LC time constants on the order of 100 ns. One design includes 20 bricks per stage, and delivers a peak electrical power of 1.05 TW to a matched-impedance 1.22-Ω load. The design generates 113 kV per stage and has a maximum energy efficiency of 89%. The other design includes a single brick per stage, delivers 68 GW to a matched-impedance 19-Ω load, generates 113 kV per stage, and has a maximum energy efficiency of 90%. For a given electrical-power-output time history, an IMG is less expensive and slightly more efficient than a linear transformer driver, since an IMG does not use ferromagnetic cores.

  20. Impedance-matched Marx generators

    Science.gov (United States)

    Stygar, W. A.; LeChien, K. R.; Mazarakis, M. G.; Savage, M. E.; Stoltzfus, B. S.; Austin, K. N.; Breden, E. W.; Cuneo, M. E.; Hutsel, B. T.; Lewis, S. A.; McKee, G. R.; Moore, J. K.; Mulville, T. D.; Muron, D. J.; Reisman, D. B.; Sceiford, M. E.; Wisher, M. L.

    2017-04-01

    We have conceived a new class of prime-power sources for pulsed-power accelerators: impedance-matched Marx generators (IMGs). The fundamental building block of an IMG is a brick, which consists of two capacitors connected electrically in series with a single switch. An IMG comprises a single stage or several stages distributed axially and connected in series. Each stage is powered by a single brick or several bricks distributed azimuthally within the stage and connected in parallel. The stages of a multistage IMG drive an impedance-matched coaxial transmission line with a conical center conductor. When the stages are triggered sequentially to launch a coherent traveling wave along the coaxial line, the IMG achieves electromagnetic-power amplification by triggered emission of radiation. Hence a multistage IMG is a pulsed-power analogue of a laser. To illustrate the IMG approach to prime power, we have developed conceptual designs of two ten-stage IMGs with L C time constants on the order of 100 ns. One design includes 20 bricks per stage, and delivers a peak electrical power of 1.05 TW to a matched-impedance 1.22 -Ω load. The design generates 113 kV per stage and has a maximum energy efficiency of 89%. The other design includes a single brick per stage, delivers 68 GW to a matched-impedance 19 -Ω load, generates 113 kV per stage, and has a maximum energy efficiency of 90%. For a given electrical-power-output time history, an IMG is less expensive and slightly more efficient than a linear transformer driver, since an IMG does not use ferromagnetic cores.

  1. Transit Matching for International Safeguards

    International Nuclear Information System (INIS)

    Gilligan, K.; Whitaker, M.; Oakberg, J.

    2015-01-01

    In 2013 the U.S. Department of Energy / National Nuclear Security Administration Office of Non-proliferation and International Security (NIS) supported a study of the International Atomic Energy Agency's (IAEA) processes and procedures for ensuring that shipments of nuclear material correspond to (match) their receipts (i.e., transit matching). Under Comprehensive Safeguards Agreements, Member States are obliged to declare such information within certain time frames. Nuclear weapons states voluntarily declare such information under INFCIRC/207. This study was funded by the NIS Next Generation Safeguards Initiative (NGSI) Concepts and Approaches program. Oak Ridge National Laboratory led the research, which included collaboration with the U.S. Nuclear Regulatory Commission, the U.S. Nuclear Material Management and Safeguards System (NMMSS), and the IAEA Section for Declared Information Analysis within the Department of Safeguards. The project studied the current transit matching methodologies, identified current challenges (e.g., level of effort and timeliness), and suggested improvements. This paper presents the recommendations that resulted from the study and discussions with IAEA staff. In particular, it includes a recommendation to collaboratively develop a set of best reporting practices for nuclear weapons states under INFCIRC/207. (author)

  2. Mode conversion in hybrid optical fiber coupler

    Science.gov (United States)

    Stasiewicz, Karol A.; Marc, P.; Jaroszewicz, Leszek R.

    2012-04-01

    Designing of all in-line fiber optic systems with a supercontinuum light source gives some issues. The use of a standard single mode fiber (SMF) as an input do not secure single mode transmission in full wavelength range. In the paper, the experimental results of the tested hybrid fiber optic coupler were presented. It was manufactured by fusing a standard single mode fiber (SMF28) and a photonic crystal fiber (PCF). The fabrication process is based on the standard fused biconical taper technique. Two types of large mode area fibers (LMA8 and LAM10 NKT Photonics) with different air holes arrangements were used as the photonic crystal fiber. Spectral characteristics within the range of 800 nm - 1700 nm were presented. All process was optimized to obtain a mode conversion between SMF and PCF and to reach a single mode transmission in the PCF output of the coupler.

  3. A comparative study between matched and mis-matched projection/back projection pairs used with ASIRT reconstruction method

    International Nuclear Information System (INIS)

    Guedouar, R.; Zarrad, B.

    2010-01-01

    For algebraic reconstruction techniques both forward and back projection operators are needed. The ability to perform accurate reconstruction relies fundamentally on the forward projection and back projection methods which are usually, the transpose of each other. Even though the mis-matched pairs may introduce additional errors during the iterative process, the usefulness of mis-matched projector/back projector pairs has been proved in image reconstruction. This work investigates the performance of matched and mis-matched reconstruction pairs using popular forward projectors and their transposes when used in reconstruction tasks with additive simultaneous iterative reconstruction techniques (ASIRT) in a parallel beam approach. Simulated noiseless phantoms are used to compare the performance of the investigated pairs in terms of the root mean squared errors (RMSE) which are calculated between reconstructed slices and the reference in different regions. Results show that mis-matched projection/back projection pairs can promise more accuracy of reconstructed images than matched ones. The forward projection operator performance seems independent of the choice of the back projection operator and vice versa.

  4. Matched filtering of numerical relativity templates of spinning binary black holes

    International Nuclear Information System (INIS)

    Vaishnav, Birjoo; Hinder, Ian; Herrmann, Frank; Shoemaker, Deirdre

    2007-01-01

    Tremendous progress has been made towards the solution of the binary-black-hole problem in numerical relativity. The waveforms produced by numerical relativity will play a role in gravitational wave detection as either test beds for analytic template banks or as template banks themselves. As the parameter space explored by numerical relativity expands, the importance of quantifying the effect that each parameter has on first the detection of gravitational waves and then the parameter estimation of their sources increases. In light of this, we present a study of equal-mass, spinning binary-black-hole evolutions through matched filtering techniques commonly used in data analysis. We study how the match between two numerical waveforms varies with numerical resolution, initial angular momentum of the black holes, and the inclination angle between the source and the detector. This study is limited by the fact that the spinning black-hole binaries are oriented axially and the waveforms only contain approximately two and a half orbits before merger. We find that for detection purposes, spinning black holes require the inclusion of the higher harmonics in addition to the dominant mode, a condition that becomes more important as the black-hole spins increase. In addition, we conduct a preliminary investigation of how well a template of fixed spin and inclination angle can detect target templates of arbitrary but nonprecessing spin and inclination for the axial case considered here

  5. Color matching in facial prosthetics: A systematic review.

    Science.gov (United States)

    Ranabhatt, Rani; Singh, Kamleshwar; Siddharth, Ramashanker; Tripathi, Shuchi; Arya, Deeksha

    2017-01-01

    Color matching to the surrounding skin is extremely important in patients wearing maxillofacial prostheses. It is of utmost importance to know the different techniques of color matching and coloring in maxillofacial prostheses. The purpose of this study is to review the literature data with regard to color matching in maxillofacial prosthetics. An electronic search of peer review restricted to English language dental literature was conducted to identify the relevant scientific article on color matching and coloring in maxillofacial prostheses. The publication year was up to December 2015 so that the search could include all the articles provided in that particular database. Two independent observers independently read the abstracts and later preselected full-text articles. A full-text review was carried out only for 15 articles. Out of the 15 articles, 7 were related to coloring using tinting, spraying, milling, and use of commercial cosmetics. Three studies were related to shade matching in maxillofacial prostheses. Two studies conducted the measurement of color in maxillofacial prostheses. Only one study had explained color and its relevance in maxillofacial prosthetics. Only one study was done for reproducing silicone shade guide matching Indian skin color. In addition, a single pilot study was done to measure facial skin and lip color in a human population sample stratified by race, gender, and age. Currently, there is no evidence discussing the best technique available for perfectly matching the color for the fabrication of maxillofacial prostheses. However, the latest instruments such as spectrophotometer and colorimeters are believed to have improved efficiency in matching the color.

  6. SNV's modes of ordering

    NARCIS (Netherlands)

    Hummel, John; Duim, van der Rene

    2016-01-01

    This article adopts an aidnographic approach to examine how internal organizational modes of ordering have influenced tourism development practices of SNV Netherlands Development Organisation (SNV). Our research revealed six modes of ordering: administration, project management, enterprising,

  7. Presentation Technique

    International Nuclear Information System (INIS)

    Froejmark, M.

    1992-10-01

    The report presents a wide, easily understandable description of presentation technique and man-machine communication. General fundamentals for the man-machine interface are illustrated, and the factors that affect the interface are described. A model is presented for describing the operators work situation, based on three different levels in the operators behaviour. The operator reacts routinely in the face of simple, known problems, and reacts in accordance with predetermined plans in the face of more complex, recognizable problems. Deep fundamental knowledge is necessary for truly complex questions. Today's technical status and future development have been studied. In the future, the operator interface will be based on standard software. Functions such as zooming, integration of video pictures, and sound reproduction will become common. Video walls may be expected to come into use in situations in which several persons simultaneously need access to the same information. A summary of the fundamental rules for the design of good picture ergonomics and design requirements for control rooms are included in the report. In conclusion, the report describes a presentation technique within the Distribution Automation and Demand Side Management area and analyses the know-how requirements within Vattenfall. If different systems are integrated, such as geographical information systems and operation monitoring systems, strict demands are made on the expertise of the users for achieving a user-friendly technique which is matched to the needs of the human being. (3 figs.)

  8. Modes of log gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Hohm, Olaf; Rosseel, Jan; Townsend, Paul K.

    2011-01-01

    The physical modes of a recently proposed D-dimensional "critical gravity'', linearized about its anti-de Sitter vacuum, are investigated. All "log mode'' solutions, which we categorize as "spin-2'' or "Proca'', arise as limits of the massive spin-2 modes of the noncritical theory. The linearized

  9. A simulated rugby match protocol induces physiological fatigue ...

    African Journals Online (AJOL)

    Background: A rugby union game consists of 80 minutes of strenuous exertion. Forwards are required to participate in the arduous activity of scrummaging throughout a game. Objectives: The purpose of this study was to identify whether rugby-match simulated fatigue modified individual scrummaging technique and ...

  10. New beam shaping: Matched filtering combined with GPC

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    2010-01-01

    We adapt concepts frolll matched filtering 10 propose a method for generating rcconligurablc multiple beams. Combined with the Generalized Phase Contrast (GPC) technique, the proposed method coined mGPC can yield dynamically rcconfigurablc optical beam 31rdYS wilh high light efficiency for optica...

  11. Reliable Record Matching for a College Admissions System.

    Science.gov (United States)

    Fitt, Paul D.

    Prospective student data, supplied by various national college testing and student search services, can be matched with existing student records in a college admissions database. Instead of relying on one unique record identifier, such as the student's social security number, a technique has been developed that is based on a number of common data…

  12. Space and Astrophysical Plasmas: Matched filtering-parameter ...

    Indian Academy of Sciences (India)

    The parameters estimated from the theoretical and experimental whistler curves are matched to have higher accuracy using digital filters. This yields a resolution ten times better in the time domain. We have tested the applicability of this technique for the analysis of whistlers recorded at Varanasi. It is found that the whistlers ...

  13. Employment Effects of Service Offshoring: Evidence from Matched Firms

    OpenAIRE

    Rosario Crinò

    2009-01-01

    This paper studies the effects of service offshoring on the level and skill composition of domestic employment, using a rich data set of Italian firms and propensity score matching techniques. The results show that service offshoring has no effect on the level of employment but changes its composition in favor of high skilled workers.

  14. Turbine adapted maps for turbocharger engine matching

    Energy Technology Data Exchange (ETDEWEB)

    Tancrez, M. [PSA - Peugeot Citroen, 18 rue des fauvelles, La Garenne-Colombes (France); Galindo, J.; Guardiola, C.; Fajardo, P.; Varnier, O. [CMT - Motores Termicos, Universidad Politecnica de Valencia (Spain)

    2011-01-15

    This paper presents a new representation of the turbine performance maps oriented for turbocharger characterization. The aim of this plot is to provide a more compact and suited form to implement in engine simulation models and to interpolate data from turbocharger test bench. The new map is based on the use of conservative parameters as turbocharger power and turbine mass flow to describe the turbine performance in all VGT positions. The curves obtained are accurately fitted with quadratic polynomials and simple interpolation techniques give reliable results. Two turbochargers characterized in an steady flow rig were used for illustrating the representation. After being implemented in a turbocharger submodel, the results obtained with the model have been compared with success against turbine performance evaluated in engine tests cells. A practical application in turbocharger matching is also provided to show how this new map can be directly employed in engine design. (author)

  15. Sequence Matching Analysis for Curriculum Development

    Directory of Open Access Journals (Sweden)

    Liem Yenny Bendatu

    2015-06-01

    Full Text Available Many organizations apply information technologies to support their business processes. Using the information technologies, the actual events are recorded and utilized to conform with predefined model. Conformance checking is an approach to measure the fitness and appropriateness between process model and actual events. However, when there are multiple events with the same timestamp, the traditional approach unfit to result such measures. This study attempts to develop a sequence matching analysis. Considering conformance checking as the basis of this approach, this proposed approach utilizes the current control flow technique in process mining domain. A case study in the field of educational process has been conducted. This study also proposes a curriculum analysis framework to test the proposed approach. By considering the learning sequence of students, it results some measurements for curriculum development. Finally, the result of the proposed approach has been verified by relevant instructors for further development.

  16. Low-bending loss and single-mode operation in few-mode optical fiber

    Science.gov (United States)

    Yin, Ping; Wang, Hua; Chen, Ming-Yang; Wei, Jin; Cai, Zhi-Min; Li, Lu-Ming; Yang, Ji-Hai; Zhu, Yuan-Feng

    2016-10-01

    The technique of eliminating the higher-order modes in a few-mode optical fiber is proposed. The fiber is designed with a group of defect modes in the cladding. The higher-order modes in the fiber can be eliminated by bending the fiber to induce strong coupling between the defect modes and the higher-order modes. Numerical simulation shows the bending losses of the LP01 mode are lower than 1.5×10-4 dB/turn for the wavelength shorter than 1.625 μm. The proposed fiber can be bent multiple turns at small bending radius which are preferable for FTTH related applications.

  17. Topological zero modes in Monte Carlo simulations

    International Nuclear Information System (INIS)

    Dilger, H.

    1994-08-01

    We present an improvement of global Metropolis updating steps, the instanton hits, used in a hybrid Monte Carlo simulation of the two-flavor Schwinger model with staggered fermions. These hits are designed to change the topological sector of the gauge field. In order to match these hits to an unquenched simulation with pseudofermions, the approximate zero mode structure of the lattice Dirac operator has to be considered explicitly. (orig.)

  18. Dense real-time stereo matching using memory efficient semi-global-matching variant based on FPGAs

    Science.gov (United States)

    Buder, Maximilian

    2012-06-01

    This paper presents a stereo image matching system that takes advantage of a global image matching method. The system is designed to provide depth information for mobile robotic applications. Typical tasks of the proposed system are to assist in obstacle avoidance, SLAM and path planning. Mobile robots pose strong requirements about size, energy consumption, reliability and output quality of the image matching subsystem. Current available systems either rely on active sensors or on local stereo image matching algorithms. The first are only suitable in controlled environments while the second suffer from low quality depth-maps. Top ranking quality results are only achieved by an iterative approach using global image matching and color segmentation techniques which are computationally demanding and therefore difficult to be executed in realtime. Attempts were made to still reach realtime performance with global methods by simplifying the routines. The depth maps are at the end almost comparable to local methods. An equally named semi-global algorithm was proposed earlier that shows both very good image matching results and relatively simple operations. A memory efficient variant of the Semi-Global-Matching algorithm is reviewed and adopted for an implementation based on reconfigurable hardware. The implementation is suitable for realtime execution in the field of robotics. It will be shown that the modified version of the efficient Semi-Global-Matching method is delivering equivalent result compared to the original algorithm based on the Middlebury dataset. The system has proven to be capable of processing VGA sized images with a disparity resolution of 64 pixel at 33 frames per second based on low cost to mid-range hardware. In case the focus is shifted to a higher image resolution, 1024×1024-sized stereo frames may be processed with the same hardware at 10 fps. The disparity resolution settings stay unchanged. A mobile system that covers preprocessing, matching

  19. Streaming tearing mode

    Science.gov (United States)

    Shigeta, M.; Sato, T.; Dasgupta, B.

    1985-01-01

    The magnetohydrodynamic stability of streaming tearing mode is investigated numerically. A bulk plasma flow parallel to the antiparallel magnetic field lines and localized in the neutral sheet excites a streaming tearing mode more strongly than the usual tearing mode, particularly for the wavelength of the order of the neutral sheet width (or smaller), which is stable for the usual tearing mode. Interestingly, examination of the eigenfunctions of the velocity perturbation and the magnetic field perturbation indicates that the streaming tearing mode carries more energy in terms of the kinetic energy rather than the magnetic energy. This suggests that the streaming tearing mode instability can be a more feasible mechanism of plasma acceleration than the usual tearing mode instability.

  20. Mode selection laser

    DEFF Research Database (Denmark)

    2014-01-01

    The invention relates to a semiconductor mode selection laser, particularly to a VCSEL laser (200) having mode selection properties. The mode selection capability of the laser is achieved by configuring one of the reflectors (15,51) in the resonance cavity so that a reflectivity of the reflector...... (15) varies spatially in one dimension or two dimensions. Accordingly, the reflector (15) with spatially varying reflectivity is part both of the resonance cavity and the mode selection functionality of the laser. A plurality of the lasers configured with different mode selectors, i.e. different...... spatial reflector variations, may be combined to generate a laser beam containing a plurality of orthogonal modes. The laser beam may be injected into a few- mode optical fiber, e.g. for the purpose of optical communication. The VCSEL may have intra-cavity contacts (31,37) and a Tunnel junction (33...

  1. Comparison of Various Techniques in the Analysis of Waveguide Transitions

    Science.gov (United States)

    1991-08-01

    rectangular TEjo to circular TEol mode transducer. Also included are new results regarding the sensitivity of the computed solution to the choice of...are applied to an X- band model of the Marie rectangular TEjo to circular TEO, mode transducer,’ ° and the resultant data are compared with...the TEjo mode is capable of propagation. The abrupt (L = 0) case was analyzed using two methods, namely, a nine-mode mode-matching solution and a 3 Pr

  2. A Condition Number for Non-Rigid Shape Matching

    KAUST Repository

    Ovsjanikov, Maks

    2011-08-01

    © 2011 The Author(s). Despite the large amount of work devoted in recent years to the problem of non-rigid shape matching, practical methods that can successfully be used for arbitrary pairs of shapes remain elusive. In this paper, we study the hardness of the problem of shape matching, and introduce the notion of the shape condition number, which captures the intuition that some shapes are inherently more difficult to match against than others. In particular, we make a connection between the symmetry of a given shape and the stability of any method used to match it while optimizing a given distortion measure. We analyze two commonly used classes of methods in deformable shape matching, and show that the stability of both types of techniques can be captured by the appropriate notion of a condition number. We also provide a practical way to estimate the shape condition number and show how it can be used to guide the selection of landmark correspondences between shapes. Thus we shed some light on the reasons why general shape matching remains difficult and provide a way to detect and mitigate such difficulties in practice.

  3. Whispering gallery mode sensors

    Science.gov (United States)

    Foreman, Matthew R.; Swaim, Jon D.; Vollmer, Frank

    2015-01-01

    We present a comprehensive overview of sensor technology exploiting optical whispering gallery mode (WGM) resonances. After a short introduction we begin by detailing the fundamental principles and theory of WGMs in optical microcavities and the transduction mechanisms frequently employed for sensing purposes. Key recent theoretical contributions to the modeling and analysis of WGM systems are highlighted. Subsequently we review the state of the art of WGM sensors by outlining efforts made to date to improve current detection limits. Proposals in this vein are numerous and range, for example, from plasmonic enhancements and active cavities to hybrid optomechanical sensors, which are already working in the shot noise limited regime. In parallel to furthering WGM sensitivity, efforts to improve the time resolution are beginning to emerge. We therefore summarize the techniques being pursued in this vein. Ultimately WGM sensors aim for real-world applications, such as measurements of force and temperature, or alternatively gas and biosensing. Each such application is thus reviewed in turn, and important achievements are discussed. Finally, we adopt a more forward-looking perspective and discuss the outlook of WGM sensors within both a physical and biological context and consider how they may yet push the detection envelope further. PMID:26973759

  4. On the use of INS to improve Feature Matching

    Science.gov (United States)

    Masiero, A.; Guarnieri, A.; Vettore, A.; Pirotti, F.

    2014-11-01

    The continuous technological improvement of mobile devices opens the frontiers of Mobile Mapping systems to very compact systems, i.e. a smartphone or a tablet. This motivates the development of efficient 3D reconstruction techniques based on the sensors typically embedded in such devices, i.e. imaging sensors, GPS and Inertial Navigation System (INS). Such methods usually exploits photogrammetry techniques (structure from motion) to provide an estimation of the geometry of the scene. Actually, 3D reconstruction techniques (e.g. structure from motion) rely on use of features properly matched in different images to compute the 3D positions of objects by means of triangulation. Hence, correct feature matching is of fundamental importance to ensure good quality 3D reconstructions. Matching methods are based on the appearance of features, that can change as a consequence of variations of camera position and orientation, and environment illumination. For this reason, several methods have been developed in recent years in order to provide feature descriptors robust (ideally invariant) to such variations, e.g. Scale-Invariant Feature Transform (SIFT), Affine SIFT, Hessian affine and Harris affine detectors, Maximally Stable Extremal Regions (MSER). This work deals with the integration of information provided by the INS in the feature matching procedure: a previously developed navigation algorithm is used to constantly estimate the device position and orientation. Then, such information is exploited to estimate the transformation of feature regions between two camera views. This allows to compare regions from different images but associated to the same feature as seen by the same point of view, hence significantly easing the comparison of feature characteristics and, consequently, improving matching. SIFT-like descriptors are used in order to ensure good matching results in presence of illumination variations and to compensate the approximations related to the estimation

  5. Single-Mode VCSELs

    Science.gov (United States)

    Larsson, Anders; Gustavsson, Johan S.

    The only active transverse mode in a truly single-mode VCSEL is the fundamental mode with a near Gaussian field distribution. A single-mode VCSEL produces a light beam of higher spectral purity, higher degree of coherence and lower divergence than a multimode VCSEL and the beam can be more precisely shaped and focused to a smaller spot. Such beam properties are required in many applications. In this chapter, after discussing applications of single-mode VCSELs, we introduce the basics of fields and modes in VCSELs and review designs implemented for single-mode emission from VCSELs in different materials and at different wavelengths. This includes VCSELs that are inherently single-mode as well as inherently multimode VCSELs where higher-order modes are suppressed by mode selective gain or loss. In each case we present the current state-of-the-art and discuss pros and cons. At the end, a specific example with experimental results is provided and, as a summary, the most promising designs based on current technologies are identified.

  6. Monetary Exchange with Multilateral Matching

    DEFF Research Database (Denmark)

    Julien, Benoît; Kennes, John; King, Ian

    This paper analyzes monetary exchange in a search model allowing for multilateral matches to be formed, according to a standard urn-ballprocess. We consider three physical environments: indivisible goods and money, divisible goods and indivisible money, and divisible goods and money. We compare....... In particular, surplus maximization can be achieved in this setting, in equilibrium, with a positive money supply. Moreover, with flexible prices and directed search, the first best allocation can be attained through price posting or through auctions with lotteries, but not through auctions without lotteries....... Finally, analysis of the case of divisible goods and money can be performed without the assumption of large families (as in Shi (1997)) or the day and night structure of Lagos and Wright (2005)....

  7. Extracting Operating Modes from Building Electrical Load Data: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Frank, S.; Polese, L. G.; Rader, E.; Sheppy, M.; Smith, J.

    2012-01-01

    Empirical techniques for characterizing electrical energy use now play a key role in reducing electricity consumption, particularly miscellaneous electrical loads, in buildings. Identifying device operating modes (mode extraction) creates a better understanding of both device and system behaviors. Using clustering to extract operating modes from electrical load data can provide valuable insights into device behavior and identify opportunities for energy savings. We present a fast and effective heuristic clustering method to identify and extract operating modes in electrical load data.

  8. Vibrational mode analysis using maximum likelihood and maximum entropy

    International Nuclear Information System (INIS)

    Redondo, A.; Sinha, D.N.

    1993-01-01

    A simple algorithm is presented that uses the maximum likelihood and maximum entropy approaches to determine the vibrational modes of elastic bodies. This method assumes that the vibrational frequencies have been previously determined, but the modes to which they correspond are unknown. Although the method is illustrated through the analysis of simulated vibrational modes for a flat rectangular plate, it has broad applicability to any experimental technique in which spectral frequencies can be associated to specific modes by means of a mathematical model

  9. Establishing Keypoint Matches on Multimodal Images with Bootstrap Strategy and Global Information.

    Science.gov (United States)

    Li, Yong; Jin, Hongbin; Wu, Jiatao; Liu, Jie

    2017-04-19

    This paper proposes an algorithm of building keypoint matches on multimodal images by combining a bootstrap process and global information. The correct ratio of keypoint matches built with descriptors is typically very low on multimodal images of large spectral difference. To identify correct matches, global information is utilized for evaluating keypoint matches and a bootstrap technique is employed to reduce the computational cost. A keypoint match determines a transformation T and a similarity metric between the reference and the transformed test image by T. The similarity metric encodes global information over entire images, and hence a higher similarity indicates the match can bring more image content into alignment, implying it tends to be correct. Unfortunately, exhausting triplets/quadruples of matches for affine/projective transformation is computationally intractable when the number of keypoints is large. To reduce the computational cost, a bootstrap technique is employed that starts from single matches for a translation and rotation model, and goes increasingly to quadruples of four matches for a projective model. The global information screens for "good" matches at each stage and the bootstrap strategy makes the screening process computationally feasible. Experimental results show that the proposed method can establish reliable keypoint matches on challenging multimodal images of strong multimodality.

  10. 24 CFR 576.51 - Matching funds.

    Science.gov (United States)

    2010-04-01

    ... specific statutory subtitle from which ESG funds are provided), as well as State, local, and private... match a previous ESG grant may not be used to match a subsequent grant award under this part. A grantee...

  11. Efficient wave-function matching approach for quantum transport calculations

    DEFF Research Database (Denmark)

    Sørensen, Hans Henrik Brandenborg; Hansen, Per Christian; Petersen, Dan Erik

    2009-01-01

    . This approach makes it feasible to apply iterative techniques to efficiently determine the few required bulk modes, which allows for a significant reduction of the computational expense of the WFM method. We illustrate the efficiency of the method on a carbon nanotube field-effect-transistor device displaying...... band-to-band tunneling and modeled within the semiempirical extended Hückel theory framework....

  12. Streaming gravity mode instability

    International Nuclear Information System (INIS)

    Wang Shui.

    1989-05-01

    In this paper, we study the stability of a current sheet with a sheared flow in a gravitational field which is perpendicular to the magnetic field and plasma flow. This mixing mode caused by a combined role of the sheared flow and gravity is named the streaming gravity mode instability. The conditions of this mode instability are discussed for an ideal four-layer model in the incompressible limit. (author). 5 refs

  13. Scanless multitarget-matching multiphoton excitation fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Junpeng Qiu

    2018-03-01

    Full Text Available Using the combination of a reflective blazed grating and a reflective phase-only diffractive spatial light modulator (SLM, scanless multitarget-matching multiphoton excitation fluorescence microscopy (SMTM-MPM was achieved. The SLM shaped an incoming mode-locked, near-infrared Ti:sapphire laser beam into an excitation pattern with addressable shapes and sizes that matched the samples of interest in the field of view. Temporal and spatial focusing were simultaneously realized by combining an objective lens and a blazed grating. The fluorescence signal from illuminated areas was recorded by a two-dimensional sCMOS camera. Compared with a conventional temporal focusing multiphoton microscope, our microscope achieved effective use of the laser power and decreased photodamage with higher axial resolution.

  14. Coupled tearing modes in plasmas with differential rotation

    International Nuclear Information System (INIS)

    Dewar, R.L.; Persson, M.

    1993-08-01

    The global asymptotic matching equations for multiple coupled resistive modes of arbitrary parity in a cylindrical plasma are derived. Three different variational principles are given for the outer region matching data, while the inner-region analysis features a careful treatment of the symmetry-breaking effect of a gradient in the equilibrium current for a zero-β slab model. It is concluded that the usual constant-ψ result remains valid and constrains the matrix matching formalism. The dispersion relation is compared with initial value calculations of a double tearing mode when there are small relative rotation velocities between the rational surfaces. In treating differential rotation within the asymptotic matching formalism, flow is ignored in the outer region and is assumed to affect the inner response solely through a Doppler shift. It is shown that the relative rotation can have a strong stabilizing effect by making all but one rational surface effectively ideal. 40 refs., 6 figs

  15. Antipastorialism : Resistant Georgic Mode

    National Research Council Canada - National Science Library

    Zimmerman, Donald

    2000-01-01

    .... Abolitionists, women, Afro-British slaves, and those who protested land enclosure developed a multivalent, resistant mode of writing, which I name 'antipastoralism', that countered orthodox, poetical...

  16. Dual-Mode Combustor

    Science.gov (United States)

    Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)

    2013-01-01

    A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

  17. Nonlinear drift tearing mode

    International Nuclear Information System (INIS)

    Zelenyj, L.M.; Kuznetsova, M.M.

    1989-01-01

    Nonlinear study of magnetic perturbation development under single-mode conditions in collision-free plasma in configurations with the magnetic field shear is investigated. Results are obtained with regard of transverse component of electrical field and its effect on ion dynamics within wide range of ion Larmor radius value and values of magnetic field shear. Increments of nonlinear drift tearing mode are obtained and it is shown that excitation drastic conditions of even linearly stable modes are possible. Mechanism of instability nonlinear stabilization is considered and the value of magnetic island at the saturation threshold is estimeted. Energy of nonlinear drift tearing mode is discussed

  18. Database crime to crime match rate calculation.

    Science.gov (United States)

    Buckleton, John; Bright, Jo-Anne; Walsh, Simon J

    2009-06-01

    Guidance exists on how to count matches between samples in a crime sample database but we are unable to locate a definition of how to estimate a match rate. We propose a method that does not proceed from the match counting definition but which has a strong logic.

  19. Small sample properties of matching with caliper

    OpenAIRE

    Paweł Strawiński

    2012-01-01

    A caliper mechanism is a common tool used to prevent from inexact matches. The existing literature discusses asymptotic properties of matching with caliper. In this simulation study we investigate properties in small and medium sized samples. We show that caliper causes a significant bias of the ATT estimator and raises its variance in comparison to one-to-one matching.

  20. Robust weighted scan matching with quadtrees

    NARCIS (Netherlands)

    Visser, A.; Slamet, B.A.; Pfingsthorn, M.

    2009-01-01

    This paper presents the improvement of the robustness and accuracy of the weighted scan matching algorithm matching against the union of earlier acquired scans. The approach allows to reduce the correspondence error, which is explicitly modeled in the weighted scan matching algorithm, by providing a

  1. Connections between the matching and chromatic polynomials

    Directory of Open Access Journals (Sweden)

    E. J. Farrell

    1992-01-01

    Full Text Available The main results established are (i a connection between the matching and chromatic polynomials and (ii a formula for the matching polynomial of a general complement of a subgraph of a graph. Some deductions on matching and chromatic equivalence and uniqueness are made.

  2. Waveguide damage detection by the matching pursuit approach employing the dispersion-based chirp functions.

    Science.gov (United States)

    Hong, Jin-Chul; Sun, Kyung Ho; Kim, Yoon Young

    2006-03-01

    If the wave mode used in guided wave non-destructive inspection is dispersive, reflected pulses from damaged parts may be significantly distorted due to wave dispersion. The main concern, in this case, is how to detect the reflected pulses in noisy signals, and to extract meaningful damage information from the detected pulses. However, current signal processing techniques used for guided wave inspection do not account for pulse dispersion, so the extracted information is often not so accurate. The objective of this study is to develop an efficient technique to deal with dispersed pulses for guided-wave nondestructive evaluation. Our idea is to model dispersed pulses by chirp functions of special form that can simulate up to quadratically varying group delay. To determine the parameters of the chirp functions approximating dispersed, reflected pulses, an adaptive matching pursuit algorithm is employed. Once the characterizing parameters are found, the damage location and extent can be estimated. The proposed method is tested with experimentally measured signals of longitudinal waves in a circular cylinder.

  3. Measurement of attenuation coefficient of core and cladding modes in Bragg fiber

    Science.gov (United States)

    Frank, Milan; Jelínek, Michal; Kubeček, Václav; Matějec, Vlastimil; Podrazký, Ondřej; Kašík, Ivan

    2017-12-01

    In this contribution a new method for determination of transmission characteristics and mechanism of optical radiation propagation in Bragg fibers is described. The investigated Bragg fibers are designed for high-power laser radiation delivery. Attenuation coefficient and coupling efficiency are usually measured using simple cutback method for optimum mode matching of the incident radiation to the fiber mode. Our current approach is based on the cut-back technique but we also investigate the dependence of the mentioned parameters on radial position of the excitation mode from the fiber axis. In addition, using the imaging of the measured fiber output face on a CCD camera, the spatial profile of the propagated beam can be obtained. For this reason this method is suitable for delivered laser mode control. The investigated Bragg fiber consisted of the 26um diameter silica core surrounded by three pairs of circular Bragg layers. Each pair is composed of one layer with a high and one layer with a low refractive index being characterized by a refractive-index contrast up to 0.03. The 1064nm laser beam was focused by a telescope onto the fiber input face. The beam radius in the focal plane was 5um. The Bragg fiber output face was imaged by a 1:6 optical telescope on the CCD camera. The transmitted power and spatial beam profile were registered simultaneously for various offset from the fiber axis. After the fiber shortening, the measurement was repeated and the cut-back was performed. The lowest attenuation coefficient of 0.17dB/m corresponded to a core mode of the delivered laser radiation. In general, the attenuation was higher with a shift from the radial axis of the fiber symmetry. In the case of cladding mode excitation, the attenuation parameter shows a local minimum. This phenomenon was consistent with the refractive index profile of the tested Bragg fiber.

  4. On Tree-Constrained Matchings and Generalizations

    OpenAIRE

    Canzar, Stefan; Elbassioni, Khaled; Klau, Gunnar W.; Mestre, Julián

    2015-01-01

    htmlabstractWe consider the following \\textsc{Tree-Constrained Bipartite Matching} problem: Given two rooted trees $T_1=(V_1,E_1)$, $T_2=(V_2,E_2)$ and a weight function $w: V_1\\times V_2 \\mapsto \\mathbb{R}_+$, find a maximum weight matching $\\mathcal{M}$ between nodes of the two trees, such that none of the matched nodes is an ancestor of another matched node in either of the trees. This generalization of the classical bipartite matching problem appears, for example, in the computational ana...

  5. Real-time polarization mode dispersion monitoring system for a multiple-erbium-doped fiber amplifier, dense wavelength division multiplexing optical fiber transmission by amplified spontaneous emission modulation and acousto-optic tunable fiber scanning techniques.

    Science.gov (United States)

    Tseng, Bao-Jang; Tarn, Chen-Wen

    2009-03-01

    Without interruption or affecting the transmission of ordinary payload channels, we propose a real time polarization mode dispersion (PMD) monitoring system for long-haul, multiple erbium-doped fiber amplifier (EDFA), dense wavelength division multiplexing (DWDM) optical fiber transmission using modulated amplified spontaneous emission (ASE) of one of the EDFAs as the supervisory (SV) signal source. An acousto-optic tunable filter (AOTF) at the receiver side is adopted to scan the spectrum of the transmitted ASE SV signal. Using the fixed-analyzer method, PMDs of different wavelength bands that range from 1545 to 1580 nm of a DWDM fiber-optic communication system can be found by adaptively changing the radio frequency of the AOTF. The resolution and the measuring range of the proposed monitoring system can be significantly improved by cascading the AOTFs at the receiver side.

  6. Identifying a "default" visual search mode with operant conditioning.

    Science.gov (United States)

    Kawahara, Jun-ichiro

    2010-09-01

    The presence of a singleton in a task-irrelevant domain can impair visual search. This impairment, known as the attentional capture depends on the set of participants. When narrowly searching for a specific feature (the feature search mode), only matching stimuli capture attention. When searching broadly (the singleton detection mode), any oddball captures attention. The present study examined which strategy represents the "default" mode using an operant conditioning approach in which participants were trained, in the absence of explicit instructions, to search for a target in an ambiguous context in which one of two modes was available. The results revealed that participants behaviorally adopted the singleton detection as the default mode but reported using the feature search mode. Conscious strategies did not eliminate capture. These results challenge the view that a conscious set always modulates capture, suggesting that the visual system tends to rely on stimulus salience to deploy attention.

  7. Fuzzy Sliding Mode Control of Plate Vibrations

    Directory of Open Access Journals (Sweden)

    Manu Sharma

    2010-01-01

    Full Text Available In this paper, fuzzy logic is meshed with sliding mode control, in order to control vibrations of a cantilevered plate. Test plate is instrumented with a piezoelectric sensor patch and a piezoelectric actuator patch. Finite element method is used to obtain mathematical model of the test plate. A design approach of a sliding mode controller for linear systems with mismatched time-varying uncertainties is used in this paper. It is found that chattering around the sliding surface in the sliding mode control can be checked by the proposed fuzzy sliding mode control approach. With presented fuzzy sliding mode approach the actuator voltage time response has a smooth decay. This is important because an abrupt decay can excite higher modes in the structure. Fuzzy rule base consisting of nine rules, is generated from the sliding mode inequality. Experimental implementation of the control approach verify the theoretical findings. For experimental implementation, size of the problem is reduced using modal truncation technique. Modal displacements as well as velocities of first two modes are observed using real-time kalman observer. Real time implementation of fuzzy logic based control has always been a challenge because a given set of rules has to be executed in every sampling interval. Results in this paper establish feasibility of experimental implementation of presented fuzzy logic based controller for active vibration control.

  8. Scanner OPC signatures: automatic vendor-to-vendor OPE matching

    Science.gov (United States)

    Renwick, Stephen P.

    2009-03-01

    As 193nm lithography continues to be stretched and the k1 factor decreases, optical proximity correction (OPC) has become a vital part of the lithographer's tool kit. Unfortunately, as is now well known, the design variations of lithographic scanners from different vendors cause them to have slightly different optical-proximity effect (OPE) behavior, meaning that they print features through pitch in distinct ways. This in turn means that their response to OPC is not the same, and that an OPC solution designed for a scanner from Company 1 may or may not work properly on a scanner from Company 2. Since OPC is not inexpensive, that causes trouble for chipmakers using more than one brand of scanner. Clearly a scanner-matching procedure is needed to meet this challenge. Previously, automatic matching has only been reported for scanners of different tool generations from the same manufacturer. In contrast, scanners from different companies have been matched using expert tuning and adjustment techniques, frequently requiring laborious test exposures. Automatic matching between scanners from Company 1 and Company 2 has remained an unsettled problem. We have recently solved this problem and introduce a novel method to perform the automatic matching. The success in meeting this challenge required three enabling factors. First, we recognized the strongest drivers of OPE mismatch and are thereby able to reduce the information needed about a tool from another supplier to that information readily available from all modern scanners. Second, we developed a means of reliably identifying the scanners' optical signatures, minimizing dependence on process parameters that can cloud the issue. Third, we carefully employed standard statistical techniques, checking for robustness of the algorithms used and maximizing efficiency. The result is an automatic software system that can predict an OPC matching solution for scanners from different suppliers without requiring expert intervention.

  9. Matching roots to their environment.

    Science.gov (United States)

    White, Philip J; George, Timothy S; Gregory, Peter J; Bengough, A Glyn; Hallett, Paul D; McKenzie, Blair M

    2013-07-01

    Plants form the base of the terrestrial food chain and provide medicines, fuel, fibre and industrial materials to humans. Vascular land plants rely on their roots to acquire the water and mineral elements necessary for their survival in nature or their yield and nutritional quality in agriculture. Major biogeochemical fluxes of all elements occur through plant roots, and the roots of agricultural crops have a significant role to play in soil sustainability, carbon sequestration, reducing emissions of greenhouse gasses, and in preventing the eutrophication of water bodies associated with the application of mineral fertilizers. This article provides the context for a Special Issue of Annals of Botany on 'Matching Roots to Their Environment'. It first examines how land plants and their roots evolved, describes how the ecology of roots and their rhizospheres contributes to the acquisition of soil resources, and discusses the influence of plant roots on biogeochemical cycles. It then describes the role of roots in overcoming the constraints to crop production imposed by hostile or infertile soils, illustrates root phenotypes that improve the acquisition of mineral elements and water, and discusses high-throughput methods to screen for these traits in the laboratory, glasshouse and field. Finally, it considers whether knowledge of adaptations improving the acquisition of resources in natural environments can be used to develop root systems for sustainable agriculture in the future.

  10. Recent Developments in the External Conjugate-T Matching Project at JET

    International Nuclear Information System (INIS)

    Monakhov, I.; Walden, A.

    2007-01-01

    The External Conjugate-T (ECT) matching system is planned for installation on two A2 ICRH antenna arrays at JET in 2007. This will enhance the operational capabilities of the RF plant during ELMy plasma scenarios and create new opportunities for ITER-relevant matching studies. The main features of the project are discussed in the paper focusing on the specific challenges of the ECT automatic matching and arc detection in optimized ELM-tolerant configurations. A 'co/counter-clockwise' automatic control mode selection and an Advanced Wave Amplitude Comparison System (AWACS) complementing the existing VSWR monitoring are proposed as simple and viable solutions to the identified problems

  11. Mode decomposition evolution equations.

    Science.gov (United States)

    Wang, Yang; Wei, Guo-Wei; Yang, Siyang

    2012-03-01

    Partial differential equation (PDE) based methods have become some of the most powerful tools for exploring the fundamental problems in signal processing, image processing, computer vision, machine vision and artificial intelligence in the past two decades. The advantages of PDE based approaches are that they can be made fully automatic, robust for the analysis of images, videos and high dimensional data. A fundamental question is whether one can use PDEs to perform all the basic tasks in the image processing. If one can devise PDEs to perform full-scale mode decomposition for signals and images, the modes thus generated would be very useful for secondary processing to meet the needs in various types of signal and image processing. Despite of great progress in PDE based image analysis in the past two decades, the basic roles of PDEs in image/signal analysis are only limited to PDE based low-pass filters, and their applications to noise removal, edge detection, segmentation, etc. At present, it is not clear how to construct PDE based methods for full-scale mode decomposition. The above-mentioned limitation of most current PDE based image/signal processing methods is addressed in the proposed work, in which we introduce a family of mode decomposition evolution equations (MoDEEs) for a vast variety of applications. The MoDEEs are constructed as an extension of a PDE based high-pass filter (Europhys. Lett., 59(6): 814, 2002) by using arbitrarily high order PDE based low-pass filters introduced by Wei (IEEE Signal Process. Lett., 6(7): 165, 1999). The use of arbitrarily high order PDEs is essential to the frequency localization in the mode decomposition. Similar to the wavelet transform, the present MoDEEs have a controllable time-frequency localization and allow a perfect reconstruction of the original function. Therefore, the MoDEE operation is also called a PDE transform. However, modes generated from the present approach are in the spatial or time domain and can be

  12. Applications of sliding mode control

    CERN Document Server

    Ghommam, Jawhar; Zhu, Quanmin

    2017-01-01

    This book presents essential studies and applications in the context of sliding mode control, highlighting the latest findings from interdisciplinary theoretical studies, ranging from computational algorithm development to representative applications. Readers will learn how to easily tailor the techniques to accommodate their ad hoc applications. To make the content as accessible as possible, the book employs a clear route in each paper, moving from background to motivation, to quantitative development (equations), and lastly to case studies/illustrations/tutorials (simulations, experiences, curves, tables, etc.). Though primarily intended for graduate students, professors and researchers from related fields, the book will also benefit engineers and scientists from industry. .

  13. Best Practices for NPT Transit Matching

    Energy Technology Data Exchange (ETDEWEB)

    Gilligan, Kimberly V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitaker, J. Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Oakberg, John A. [Tetra Tech, Inc., Oak Ridge, TN (United States); Snow, Catherine [Sno Consulting, LLC, Sandy, UT (United States)

    2016-09-01

    Transit matching is the process for relating or matching reports of shipments and receipts submitted to the International Atomic Energy Agency (IAEA). Transit matching is a component used by the IAEA in drawing safeguards conclusions and performing investigative analysis. Transit matching is part of IAEA safeguards activities and the State evaluation process, and it is included in the annual Safeguards Implementation Report (SIR). Annually, the IAEA currently receives reports of ~900,000 nuclear material transactions, of which ~500,000 are for domestic and foreign transfers. Of these the IAEA software can automatically match (i.e., machine match) about 95% of the domestic transfers and 25% of the foreign transfers. Given the increasing demands upon IAEA resources, it is highly desirable for the machine-matching process to match as many transfers as possible. Researchers at Oak Ridge National Laboratory (ORNL) have conducted an investigation funded by the National Nuclear Security Administration through the Next Generation Safeguards Initiative to identify opportunities to strengthen IAEA transit matching. Successful matching, and more specifically machine matching, is contingent on quality data from the reporting States. In February 2016, ORNL hosted representatives from three States, the IAEA, and Euratom to share results from past studies and to discuss the processes, policies, and procedures associated with State reporting for transit matching. Drawing on each entity's experience and knowledge, ORNL developed a best practices document to be shared with the international safeguards community to strengthen transit matching. This paper shares the recommendations that resulted from this strategic meeting and the next steps being taken to strengthen transit matching.

  14. Probabilistic seismic history matching using binary images

    Science.gov (United States)

    Davolio, Alessandra; Schiozer, Denis Jose

    2018-02-01

    Currently, the goal of history-matching procedures is not only to provide a model matching any observed data but also to generate multiple matched models to properly handle uncertainties. One such approach is a probabilistic history-matching methodology based on the discrete Latin Hypercube sampling algorithm, proposed in previous works, which was particularly efficient for matching well data (production rates and pressure). 4D seismic (4DS) data have been increasingly included into history-matching procedures. A key issue in seismic history matching (SHM) is to transfer data into a common domain: impedance, amplitude or pressure, and saturation. In any case, seismic inversions and/or modeling are required, which can be time consuming. An alternative to avoid these procedures is using binary images in SHM as they allow the shape, rather than the physical values, of observed anomalies to be matched. This work presents the incorporation of binary images in SHM within the aforementioned probabilistic history matching. The application was performed with real data from a segment of the Norne benchmark case that presents strong 4D anomalies, including softening signals due to pressure build up. The binary images are used to match the pressurized zones observed in time-lapse data. Three history matchings were conducted using: only well data, well and 4DS data, and only 4DS. The methodology is very flexible and successfully utilized the addition of binary images for seismic objective functions. Results proved the good convergence of the method in few iterations for all three cases. The matched models of the first two cases provided the best results, with similar well matching quality. The second case provided models presenting pore pressure changes according to the expected dynamic behavior (pressurized zones) observed on 4DS data. The use of binary images in SHM is relatively new with few examples in the literature. This work enriches this discussion by presenting a new

  15. Security and matching of partial fingerprint recognition systems

    Science.gov (United States)

    Jea, Tsai-Yang; Chavan, Viraj S.; Govindaraju, Venu; Schneider, John K.

    2004-08-01

    Despite advances in fingerprint identification techniques, matching incomplete or partial fingerprints still poses a difficult challenge. While the introduction of compact silicon chip-based sensors that capture only a part of the fingerprint area have made this problem important from a commercial perspective, there is also considerable interest on the topic for processing partial and latent fingerprints obtained at crime scenes. Attempts to match partial fingerprints using singular ridge structures-based alignment techniques fail when the partial print does not include such structures (e.g., core or delta). We present a multi-path fingerprint matching approach that utilizes localized secondary features derived using only the relative information of minutiae. Since the minutia-based fingerprint representation, is an ANSI-NIST standard, our approach has the advantage of being directly applicable to already existing databases. We also analyze the vulnerability of partial fingerprint identification systems to brute force attacks. The described matching approach has been tested on one of FVC2002"s DB1 database11. The experimental results show that our approach achieves an equal error rate of 1.25% and a total error rate of 1.8% (with FAR at 0.2% and FRR at 1.6%).

  16. Individuation instructions decrease the Cross-Race Effect in a face matching task

    Directory of Open Access Journals (Sweden)

    2015-09-01

    Conclusions: Individuation instructions are an effective moderator of the CRE even within a face matching paradigm. Since unfamiliar face matching tasks most closely simulate document verification tasks, specifically passport screening, instructional techniques such as these may improve task performance within applied settings of significant practical importance.

  17. Using the Internet to Promote Health Behavior Change: A Systematic Review and Meta-analysis of the Impact of Theoretical Basis, Use of Behavior Change Techniques, and Mode of Delivery on Efficacy

    OpenAIRE

    Webb, Thomas L; Joseph, Judith; Yardley, Lucy; Michie, Susan

    2010-01-01

    Background: The Internet is increasingly used as a medium for the delivery of interventions designed to promote health behavior change. However, reviews of these interventions to date have not systematically identified intervention characteristics and linked these to effectiveness.Objectives: The present review sought to capitalize on recently published coding frames for assessing use of theory and behavior change techniques to investigate which characteristics of Internet-based interventions...

  18. Using the internet to promote health behavior change: A\\ud systematic review and meta-analysis of the impact of theoretical basis, use of behavior change techniques, and mode of delivery on efficacy

    OpenAIRE

    Webb, Thomas L.; Joseph, Judith; Yardley, Lucy; Michie, Susan

    2010-01-01

    Background: The Internet is increasingly used as a medium for the delivery of interventions designed to promote health behavior change. However, reviews of these interventions to date have not systematically identified intervention characteristics and linked these to effectiveness.\\ud \\ud Objectives: The present review sought to capitalize on recently published coding frames for assessing use of theory and behavior change techniques to investigate which characteristics of Internet-based inter...

  19. Global image registration using a symmetric block-matching approach.

    Science.gov (United States)

    Modat, Marc; Cash, David M; Daga, Pankaj; Winston, Gavin P; Duncan, John S; Ourselin, Sébastien

    2014-07-01

    Most medical image registration algorithms suffer from a directionality bias that has been shown to largely impact subsequent analyses. Several approaches have been proposed in the literature to address this bias in the context of nonlinear registration, but little work has been done for global registration. We propose a symmetric approach based on a block-matching technique and least-trimmed square regression. The proposed method is suitable for multimodal registration and is robust to outliers in the input images. The symmetric framework is compared with the original asymmetric block-matching technique and is shown to outperform it in terms of accuracy and robustness. The methodology presented in this article has been made available to the community as part of the NiftyReg open-source package.

  20. Low-field accelerator structure couplers and design techniques

    Directory of Open Access Journals (Sweden)

    Christopher Nantista

    2004-07-01

    Full Text Available Recent experience with X-band accelerator structure development has shown the rf input coupler to be the region most prone to rf breakdown and degradation, effectively limiting the operating gradient. A major factor in this appears to be high magnetic fields at the sharp edges of the coupling irises. As a first response to this problem, couplers with rounded and thickened iris horns have been employed and successfully tested at high power. To further reduce fields for higher power flow, conceptually new coupler designs have been developed, in which power is coupled through the broad wall of the feed waveguide, rather than through terminating irises. A “mode-launcher” coupler, which launches the TM_{01} mode in circular waveguide before coupling through a matching cell into the main structure, has been tested with great success. With peak surface fields below those in the body of the structure, this coupler represented a breakthrough in the Next Linear Collider structure program. The design of this coupler and of variations which use beam line space more efficiently are described here. The latter include a coupler in which power passes directly through an iris in the broad wall of the rectangular waveguide into a matching cell, also successfully implemented, and a variation which makes the waveguide itself an accelerating cell. We also discuss in some detail a couple of techniques for matching such couplers to traveling-wave structures using a field solver. The first exploits the cell number independence of a traveling-wave match, and the second optimizes using the fields of an internally driven structure.

  1. Moving Target Depth Estimation for Passive Sonar, Using Sequential Resampling Techniques

    National Research Council Canada - National Science Library

    Kraut, Shawn

    2001-01-01

    ... wave numbers of the channel modes used for the matched-field target response. Using this approach, the complex amplitudes of the modes are treated as nuisance parameters, which comprise a hidden, first-order Markov state process...

  2. Switch mode power supply

    International Nuclear Information System (INIS)

    Kim, Hui Jun

    1993-06-01

    This book concentrates on switch mode power supply. It has four parts, which are introduction of switch mode power supply with DC-DC converter such as Buck converter boost converter, Buck-boost converter and PWM control circuit, explanation for SMPS with DC-DC converter modeling and power mode control, resonance converter like resonance switch, converter, multi resonance converter and series resonance and parallel resonance converters, basic test of SMPS with PWM control circuit, Buck converter, Boost converter, flyback converter, forward converter and IC for control circuit.

  3. Surface modes in physics

    CERN Document Server

    Sernelius, Bo E

    2011-01-01

    Electromagnetic surface modes are present at all surfaces and interfaces between material of different dielectric properties. These modes have very important effects on numerous physical quantities: adhesion, capillary force, step formation and crystal growth, the Casimir effect etc. They cause surface tension and wetting and they give rise to forces which are important e.g. for the stability of colloids.This book is a useful and elegant approach to the topic, showing how the concept of electromagnetic modes can be developed as a unifying theme for a range of condensed matter physics. The

  4. Study of complex modes

    International Nuclear Information System (INIS)

    Pastrnak, J.W.

    1986-01-01

    This eighteen-month study has been successful in providing the designer and analyst with qualitative guidelines on the occurrence of complex modes in the dynamics of linear structures, and also in developing computer codes for determining quantitatively which vibration modes are complex and to what degree. The presence of complex modes in a test structure has been verified. Finite element analysis of a structure with non-proportional dumping has been performed. A partial differential equation has been formed to eliminate possible modeling errors

  5. Fractional Order Element Based Impedance Matching

    KAUST Repository

    Radwan, Ahmed Gomaa

    2014-06-24

    Disclosed are various embodiments of methods and systems related to fractional order element based impedance matching. In one embodiment, a method includes aligning a traditional Smith chart (|.alpha.|=1) with a fractional order Smith chart (|.alpha.|.noteq.1). A load impedance is located on the traditional Smith chart and projected onto the fractional order Smith chart. A fractional order matching element is determined by transitioning along a matching circle of the fractional order Smith chart based at least in part upon characteristic line impedance. In another embodiment, a system includes a fractional order impedance matching application executed in a computing device. The fractional order impedance matching application includes logic that obtains a first set of Smith chart coordinates at a first order, determines a second set of Smith chart coordinates at a second order, and determines a fractional order matching element from the second set of Smith chart coordinates.

  6. Rapid matching in Drosophila place learning

    Science.gov (United States)

    Zars, Melissa; Zars, Troy

    2009-08-01

    The level of conditioned behavior in animals is proportional to the intensity, amount, frequency, or probability of reinforcement. Interestingly, this matching can be dynamic, with performance levels following, for example, a switch in the probability of reinforcement with a short delay. We previously found that conditioned performance levels in Drosophila match reinforcement intensity in a place conditioning paradigm. Whether Drosophila can match conditioned behavior to a change in reinforcement intensity was an open question. In this study, we found that both conditioned behavior and memory levels match reinforcement intensity after a switch, and this rapid matching occurs within 2 min. Thus, fruit flies can dynamically match conditioned behavior and memory levels to a change in reinforcement intensity.

  7. Alpha particle destabilization of the TAE modes

    International Nuclear Information System (INIS)

    Cheng, C.Z.

    1991-01-01

    The high frequency, low mode number toroidicity-induced Alfven eigenmodes (TAE) are shown to be driven unstable by the circulating and/or trapped α-particles through the wave-particle resonances. For a poloidal harmonic to satisfy the resonance condition it requires that the α-particle birth speed v α ≥ v A /(2|m-nq|), where v A is the Alfven speed, m is the poloidal mode number, and n is the toroidal mode number. To destabilize the TAE modes, the inverse Landau damping associated with the α-particle pressure gradient free energy must overcome the velocity space Landau damping due to both the slowing-down α-particle and the core Maxwellian electron and ion distributions. Stability criteria in terms of the α-particle beta β α , α-particle pressure gradient parameter (ω * /ω A ) (ω * is the α-particle diamagnetic drift frequency), and (v α /v A ) parameters are presented for TFTR, CIT, and ITER tokamaks. The volume averaged α-particle beta threshold for TAE instability also depends sensitively on the core electron and ion temperature. Typically the volume averaged α-particle beta threshold is in the order of 10 -4 if the continuum damping effect is absent. Typical growth rates of the n = 1 TAE mode can be in the order of 10 -2 ω A , where ω A = v A /qR. Stability of higher n TAE modes is also studied. Other types of global Alfven waves are stable due to sideband mode continuum damping resulting from toroidal coupling effects. If the Alfven continuum gap does not exist across the whole minor radius, continuum damping exists for some poloidal harmonics. The continuum damping effect is studied by employing both a resistive MHD stability code (NOVA-R) and an analytical matching method, and the results are presented. 1 ref

  8. Detecting Weak Spectral Lines in Interferometric Data through Matched Filtering

    Science.gov (United States)

    Loomis, Ryan A.; Öberg, Karin I.; Andrews, Sean M.; Walsh, Catherine; Czekala, Ian; Huang, Jane; Rosenfeld, Katherine A.

    2018-04-01

    Modern radio interferometers enable observations of spectral lines with unprecedented spatial resolution and sensitivity. In spite of these technical advances, many lines of interest are still at best weakly detected and therefore necessitate detection and analysis techniques specialized for the low signal-to-noise ratio (S/N) regime. Matched filters can leverage knowledge of the source structure and kinematics to increase sensitivity of spectral line observations. Application of the filter in the native Fourier domain improves S/N while simultaneously avoiding the computational cost and ambiguities associated with imaging, making matched filtering a fast and robust method for weak spectral line detection. We demonstrate how an approximate matched filter can be constructed from a previously observed line or from a model of the source, and we show how this filter can be used to robustly infer a detection significance for weak spectral lines. When applied to ALMA Cycle 2 observations of CH3OH in the protoplanetary disk around TW Hya, the technique yields a ≈53% S/N boost over aperture-based spectral extraction methods, and we show that an even higher boost will be achieved for observations at higher spatial resolution. A Python-based open-source implementation of this technique is available under the MIT license at http://github.com/AstroChem/VISIBLE.

  9. Adaptive Batch Mode Active Learning.

    Science.gov (United States)

    Chakraborty, Shayok; Balasubramanian, Vineeth; Panchanathan, Sethuraman

    2015-08-01

    Active learning techniques have gained popularity to reduce human effort in labeling data instances for inducing a classifier. When faced with large amounts of unlabeled data, such algorithms automatically identify the exemplar and representative instances to be selected for manual annotation. More recently, there have been attempts toward a batch mode form of active learning, where a batch of data points is simultaneously selected from an unlabeled set. Real-world applications require adaptive approaches for batch selection in active learning, depending on the complexity of the data stream in question. However, the existing work in this field has primarily focused on static or heuristic batch size selection. In this paper, we propose two novel optimization-based frameworks for adaptive batch mode active learning (BMAL), where the batch size as well as the selection criteria are combined in a single formulation. We exploit gradient-descent-based optimization strategies as well as properties of submodular functions to derive the adaptive BMAL algorithms. The solution procedures have the same computational complexity as existing state-of-the-art static BMAL techniques. Our empirical results on the widely used VidTIMIT and the mobile biometric (MOBIO) data sets portray the efficacy of the proposed frameworks and also certify the potential of these approaches in being used for real-world biometric recognition applications.

  10. Parikh Matching in the Streaming Model

    DEFF Research Database (Denmark)

    Lee, Lap-Kei; Lewenstein, Moshe; Zhang, Qin

    2012-01-01

    |-length count vector. In the streaming model one seeks space-efficient algorithms for problems in which there is one pass over the data. We consider Parikh matching in the streaming model. To make this viable we search for substrings whose Parikh-mappings approximately match the input vector. In this paper we...... present upper and lower bounds on the problem of approximate Parikh matching in the streaming model....

  11. Matching fields and lattice points of simplices

    OpenAIRE

    Loho, Georg; Smith, Ben

    2018-01-01

    We show that the Chow covectors of a linkage matching field define a bijection of lattice points and we demonstrate how one can recover the linkage matching field from this bijection. This resolves two open questions from Sturmfels & Zelevinsky (1993) on linkage matching fields. For this, we give an explicit construction that associates a bipartite incidence graph of an ordered partition of a common set to all lattice points in a dilated simplex. Given a triangulation of a product of two simp...

  12. Tackling the challenges of matching biomedical ontologies.

    Science.gov (United States)

    Faria, Daniel; Pesquita, Catia; Mott, Isabela; Martins, Catarina; Couto, Francisco M; Cruz, Isabel F

    2018-01-15

    Biomedical ontologies pose several challenges to ontology matching due both to the complexity of the biomedical domain and to the characteristics of the ontologies themselves. The biomedical tracks in the Ontology Matching Evaluation Initiative (OAEI) have spurred the development of matching systems able to tackle these challenges, and benchmarked their general performance. In this study, we dissect the strategies employed by matching systems to tackle the challenges of matching biomedical ontologies and gauge the impact of the challenges themselves on matching performance, using the AgreementMakerLight (AML) system as the platform for this study. We demonstrate that the linear complexity of the hash-based searching strategy implemented by most state-of-the-art ontology matching systems is essential for matching large biomedical ontologies efficiently. We show that accounting for all lexical annotations (e.g., labels and synonyms) in biomedical ontologies leads to a substantial improvement in F-measure over using only the primary name, and that accounting for the reliability of different types of annotations generally also leads to a marked improvement. Finally, we show that cross-references are a reliable source of information and that, when using biomedical ontologies as background knowledge, it is generally more reliable to use them as mediators than to perform lexical expansion. We anticipate that translating traditional matching algorithms to the hash-based searching paradigm will be a critical direction for the future development of the field. Improving the evaluation carried out in the biomedical tracks of the OAEI will also be important, as without proper reference alignments there is only so much that can be ascertained about matching systems or strategies. Nevertheless, it is clear that, to tackle the various challenges posed by biomedical ontologies, ontology matching systems must be able to efficiently combine multiple strategies into a mature matching

  13. Online Job Search and Matching Quality

    OpenAIRE

    Constantin Mang

    2012-01-01

    The Internet has fundamentally changed the way workers and firms are matched on the job market. Compared to newspapers and other traditional employment resources, online job boards presumably lead to better matches by providing a wider choice of job advertisements and more sophisticated methods for finding suitable vacancies. This study investigates the association of online job search and matching quality using individual-level data from the German Socio-Economic Panel (SOEP). My results sho...

  14. Parameterized String Matching Algorithms with Application to ...

    African Journals Online (AJOL)

    In the parameterized string matching problem, a given pattern P is said to match with a sub-string t of the text T, if there exist a bijection from the symbols of P to the symbols of t. Salmela and Tarhio solve the parameterized string matching problem in sub-linear time by applying the concept of q-gram in the Horspool algorithm ...

  15. ScanProsite: detection of PROSITE signature matches and ProRule-associated functional and structural residues in proteins.

    Science.gov (United States)

    de Castro, Edouard; Sigrist, Christian J A; Gattiker, Alexandre; Bulliard, Virginie; Langendijk-Genevaux, Petra S; Gasteiger, Elisabeth; Bairoch, Amos; Hulo, Nicolas

    2006-07-01

    ScanProsite--http://www.expasy.org/tools/scanprosite/--is a new and improved version of the web-based tool for detecting PROSITE signature matches in protein sequences. For a number of PROSITE profiles, the tool now makes use of ProRules--context-dependent annotation templates--to detect functional and structural intra-domain residues. The detection of those features enhances the power of function prediction based on profiles. Both user-defined sequences and sequences from the UniProt Knowledgebase can be matched against custom patterns, or against PROSITE signatures. To improve response times, matches of sequences from UniProtKB against PROSITE signatures are now retrieved from a pre-computed match database. Several output modes are available including simple text views and a rich mode providing an interactive match and feature viewer with a graphical representation of results.

  16. Modeling of mode purity in high power gyrotrons

    International Nuclear Information System (INIS)

    Cai, S.Y.; Antonsen, T.M. Jr.; Saraph, G.P.

    1993-01-01

    Spurious mode generation at the same frequency of the operational mode in a high power gyrotron can significantly reduce the power handling capability and the stability of a gyrotron oscillator because these modes are usually not matched at the output window and thus have high absorption and reflection rates. To study the generation of this kind of mode, the authors developed a numerical model based on an existing multimode self-consistent time-dependent computer code. This model includes both TE and TM modes and accounts for mode transformations due to the waveguide inhomogeneity. With this new tool, they study the mode transformation in the gyrotron and the possibility of excitation of parasitic TE and TM modes in the up taper section due to the gyroklystron mechanism. Their preliminary results show moderate excitation of both TE and TM modes at the same frequency as the main operating mode at locations near their cutoff. Details of the model and further simulation results will be presented

  17. Application of Adaptive Sliding Mode Position Controller with PI ...

    African Journals Online (AJOL)

    PISMC) techniques for controlling the rotor position of PMDC motor drive system. In particular, since SMC is robust in the presence of the matched uncertainties and external disturbances, the desired position is perfectly tracked. In addition, the ...

  18. REDUCING THE LIKELIHOOD OF LONG TENNIS MATCHES

    Directory of Open Access Journals (Sweden)

    Tristan Barnett

    2006-12-01

    Full Text Available Long matches can cause problems for tournaments. For example, the starting times of subsequent matches can be substantially delayed causing inconvenience to players, spectators, officials and television scheduling. They can even be seen as unfair in the tournament setting when the winner of a very long match, who may have negative aftereffects from such a match, plays the winner of an average or shorter length match in the next round. Long matches can also lead to injuries to the participating players. One factor that can lead to long matches is the use of the advantage set as the fifth set, as in the Australian Open, the French Open and Wimbledon. Another factor is long rallies and a greater than average number of points per game. This tends to occur more frequently on the slower surfaces such as at the French Open. The mathematical method of generating functions is used to show that the likelihood of long matches can be substantially reduced by using the tiebreak game in the fifth set, or more effectively by using a new type of game, the 50-40 game, throughout the match

  19. Highly Scalable Matching Pursuit Signal Decomposition Algorithm

    Data.gov (United States)

    National Aeronautics and Space Administration — In this research, we propose a variant of the classical Matching Pursuit Decomposition (MPD) algorithm with significantly improved scalability and computational...

  20. 44 CFR 361.4 - Matching contributions.

    Science.gov (United States)

    2010-10-01

    ... HOMELAND SECURITY PREPAREDNESS NATIONAL EARTHQUAKE HAZARDS REDUCTION ASSISTANCE TO STATE AND LOCAL GOVERNMENTS Earthquake Hazards Reduction Assistance Program § 361.4 Matching contributions. (a) All State...

  1. PUMA: The Positional Update and Matching Algorithm

    Science.gov (United States)

    Line, J. L. B.; Webster, R. L.; Pindor, B.; Mitchell, D. A.; Trott, C. M.

    2017-01-01

    We present new software to cross-match low-frequency radio catalogues: the Positional Update and Matching Algorithm. The Positional Update and Matching Algorithm combines a positional Bayesian probabilistic approach with spectral matching criteria, allowing for confusing sources in the matching process. We go on to create a radio sky model using Positional Update and Matching Algorithm based on the Murchison Widefield Array Commissioning Survey, and are able to automatically cross-match 98.5% of sources. Using the characteristics of this sky model, we create simple simulated mock catalogues on which to test the Positional Update and Matching Algorithm, and find that Positional Update and Matching Algorithm can reliably find the correct spectral indices of sources, along with being able to recover ionospheric offsets. Finally, we use this sky model to calibrate and remove foreground sources from simulated interferometric data, generated using OSKAR (the Oxford University visibility generator). We demonstrate that there is a substantial improvement in foreground source removal when using higher frequency and higher resolution source positions, even when correcting positions by an average of 0.3 arcmin given a synthesised beam-width of 2.3 arcmin.

  2. Theory and Modeling of Lasing Modes in Vertical Cavity Surface Emitting Lasers

    Directory of Open Access Journals (Sweden)

    Benjamin Klein

    1998-01-01

    modes that the VCSEL can support are then determined by matching the gain necessary for the optical system in both magnitude and phase to the gain available from the laser's electronic system. Examples are provided.

  3. Development of the ITER ICH Transmission Line and Matching System

    Science.gov (United States)

    Rasmussen, D. A.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Swain, D. W.; Fredd, E. H.; Hosea, J.; Greenough, N.

    2011-10-01

    The ITER Ion Cyclotron Heating (ICH) System is designed to couple 20 MW of heating power for ion and electron heating. Prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system are being designed and tested. The ICH transmission lines are pressurized 300 mm diameter coaxial lines with water-cooled aluminum outer conductor and gas-cooled and water-cooled copper inner conductor. Each ICH transmission line is designed to handle 40-55 MHz power at up to 6 MW/line. A total of 8 lines split to 16 antenna inputs on two ICH antennas. Industrial suppliers have designed coaxial transmission line and matching components and prototypes will be manufactured. The prototype components will be qualified on a test stand operating at the full power and pulse length needed for ITER. The matching system must accommodated dynamic changes in the plasma loading due to ELMS and the L to H-mode transition. Passive ELM tolerance will be performed using hybrid couplers and loads, which can absorb the transient reflected power. The system is also designed to compensate for the mutual inductances of the antenna current straps to limit the peak voltages on the antenna array elements.

  4. Interferometric characterization of few-mode fibers (FMF) for mode-division multiplexing (MDM)

    DEFF Research Database (Denmark)

    Muliar, Olena; Usuga Castaneda, Mario A.; Rottwitt, Karsten

    2015-01-01

    ), commonly used in a MDM scenario. This experimental technique requires the use of a Mach-Zehnder interferometer, where the reference's path length is controlled by an optical delay line. The interference between the output beams of reference and fiber under test (FUT) is recorded on a CCD camera...... or optical modes. Mode division multiplexing (MDM) appears in this context as a promising and viable solution for such capacity increase, since it utilizes multiple spatial modes of an optical fiber as individual communication channels for data transmission. In order to evaluate its performance, a MDM system...... requires advanced characterization methods with regard to the modal content of its photonics components and in particular of the fibers involved for data transmission. In this contribution we present a time-domain interferometric technique for a full modal characterization of few mode fibers (FMF...

  5. Customer and household matching: resolving entity identity in data warehouses

    Science.gov (United States)

    Berndt, Donald J.; Satterfield, Ronald K.

    2000-04-01

    The data preparation and cleansing tasks necessary to ensure high quality data are among the most difficult challenges faced in data warehousing and data mining projects. The extraction of source data, transformation into new forms, and loading into a data warehouse environment are all time consuming tasks that can be supported by methodologies and tools. This paper focuses on the problem of record linkage or entity matching, tasks that can be very important in providing high quality data. Merging two or more large databases into a single integrated system is a difficult problem in many industries, especially in the wake of acquisitions. For example, managing customer lists can be challenging when duplicate entries, data entry problems, and changing information conspire to make data quality an elusive target. Common tasks with regard to customer lists include customer matching to reduce duplicate entries and household matching to group customers. These often O(n2) problems can consume significant resources, both in computing infrastructure and human oversight, and the goal of high accuracy in the final integrated database can be difficult to assure. This paper distinguishes between attribute corruption and entity corruption, discussing the various impacts on quality. A metajoin operator is proposed and used to organize past and current entity matching techniques. Finally, a logistic regression approach to implementing the metajoin operator is discussed and illustrated with an example. The metajoin can be used to determine whether two records match, don't match, or require further evaluation by human experts. Properly implemented, the metajoin operator could allow the integration of individual databases with greater accuracy and lower cost.

  6. Viscoelastic modes in chiral liquid crystals

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Viscoelastic properties of liquid crystals are very important for applications like display technology. However, there are not many direct techniques to study them. In this review, we describe our studies on the viscoelastic modes of some chiral liquid crystals using dynamic light scattering. We discuss ...

  7. Design of elliptical-core mode-selective photonic lanterns with six modes for MIMO-free mode division multiplexing systems.

    Science.gov (United States)

    Sai, Xiaowei; Li, Yan; Yang, Chen; Li, Wei; Qiu, Jifang; Hong, Xiaobin; Zuo, Yong; Guo, Hongxiang; Tong, Weijun; Wu, Jian

    2017-11-01

    Elliptical-core few mode fiber (EC-FMF) is used in a mode division multiplexing (MDM) transmission system to release multiple-input-multiple-output (MIMO) digital-signal-processing, which reduces the cost and the complexity of the receiver. However, EC-FMF does not match with conventional multiplexers/de-multiplexers (MUXs/DeMUXs) such as a photonic lantern, leading to extra mode coupling loss and crosstalk. We design elliptical-core mode-selective photonic lanterns (EC-MSPLs) with six modes, which can match well with EC-FMF in MIMO-free MDM systems. Simulation of the EC-MSPL using the beam propagation method was demonstrated employing a combination of either step-index or graded-index fibers with six different sizes of cores, and the taper transition length of 8 cm or 4 cm. Through numerical simulations and optimizations, both types of photonic lanterns can realize low loss transmission and low crosstalk of below -20.0  dB for all modes.

  8. Robust discrete-time nonlinear sliding mode controller with plant ...

    African Journals Online (AJOL)

    user

    multi-output linear systems with matched conditions. Some of the concepts and theoretical advances of continuous time sliding mode control are covered in literature (Won et al., 1995, Bandhyopadhyay et al., 2009) and the references there in. Due to flexibility of implementation, large classes of continuous systems are ...

  9. SEMI-GLOBAL MATCHING IN OBJECT SPACE

    Directory of Open Access Journals (Sweden)

    F. Bethmann

    2015-03-01

    Full Text Available Semi-Global Matching (SGM is a widespread algorithm for image matching which is used for very different applications, ranging from real-time applications (e.g. for generating 3D data for driver assistance systems to aerial image matching. Originally developed for stereo-image matching, several extensions have been proposed to use more than two images within the matching process (multi-baseline matching, multi-view stereo. These extensions still perform the image matching in (rectified stereo images and combine the pairwise results afterwards to create the final solution. This paper proposes an alternative approach which is suitable for the introduction of an arbitrary number of images into the matching process and utilizes image matching by using non-rectified images. The new method differs from the original SGM method mainly in two aspects: Firstly, the cost calculation is formulated in object space within a dense voxel raster by using the grey (or colour values of all images instead of pairwise cost calculation in image space. Secondly, the semi-global (path-wise minimization process is transferred into object space as well, so that the result of semi-global optimization leads to index maps (instead of disparity maps which directly indicate the 3D positions of the best matches. Altogether, this yields to an essential simplification of the matching process compared to multi-view stereo (MVS approaches. After a description of the new method, results achieved from two different datasets (close-range and aerial are presented and discussed.

  10. Pedagogical Comparison of Five Reactions Performed under Microwave Heating in Multi-Mode versus Mono-Mode Ovens: Diels-Alder Cycloaddition, Wittig Salt Formation, E2 Dehydrohalogenation to Form an Alkyne, Williamson Ether Synthesis, and Fischer Esterification

    Science.gov (United States)

    Baar, Marsha R.; Gammerdinger, William; Leap, Jennifer; Morales, Erin; Shikora, Jonathan; Weber, Michael H.

    2014-01-01

    Five reactions were rate-accelerated relative to the standard reflux workup in both multi-mode and mono-mode microwave ovens, and the results were compared to determine whether the sequential processing of a mono-mode unit could provide for better lab logistics and pedagogy. Conditions were optimized so that yields matched in both types of…

  11. Competence Matching Tool - Explanations and Implementation

    NARCIS (Netherlands)

    Herder, Eelco; Kärger, Philipp

    2010-01-01

    Herder, E., Kärger, P. (2009) Competence Matching Tool - Explanations and Implementation. The document contains the technical specification of the competence matching tool. The tool can be found at http://tencompetence.cvs.sourceforge.net/viewvc/tencompetence/wp7/CompetenceMatcher/ and the location

  12. Equilibrium and matching under price controls

    NARCIS (Netherlands)

    Herings, P.J.J.

    2015-01-01

    The paper considers a one-to-one matching with contracts model in the presence of price controls. This set-up contains two important streams in the matching literature, those with and those without monetary transfers, as special cases and allows for intermediate cases with some restrictions on the

  13. Anarchy, Stability, and Utopia: Creating Better Matchings

    Science.gov (United States)

    Anshelevich, Elliot; Das, Sanmay; Naamad, Yonatan

    We consider the loss in social welfare caused by individual rationality in matching scenarios. We give both theoretical and experimental results comparing stable matchings with socially optimal ones, as well as studying the convergence of various natural algorithms to stable matchings. Our main goal is to design mechanisms that incentivize agents to participate in matchings that are socially desirable. We show that theoretically, the loss in social welfare caused by strategic behavior can be substantial. However, under some natural distributions of utilities, we show experimentally that stable matchings attain close to the optimal social welfare. Furthermore, for certain graph structures, simple greedy algorithms for partner-switching (some without convergence guarantees) converge to stability remarkably quickly in expectation. Even when stable matchings are significantly socially suboptimal, slight changes in incentives can provide good solutions. We derive conditions for the existence of approximately stable matchings that are also close to socially optimal, which demonstrates that adding small switching costs can make socially optimal matchings stable.

  14. DOE/Industry Matching Grant Program

    International Nuclear Information System (INIS)

    Lee, John C.

    2003-01-01

    For the academic year 2001-2002, the Department of Nuclear Engineering and Radiological Sciences received $50,000 of industrial contributions, matched by a DOE grant of $35,000. We used the combined DOE/Industry Matching Grant of $85,000 toward (a) undergraduate merit scholarships and research support, (b) graduate student support, and (c) partial support of a research scientist

  15. On Tree-Constrained Matchings and Generalizations

    NARCIS (Netherlands)

    S. Canzar (Stefan); K. Elbassioni; G.W. Klau (Gunnar); J. Mestre

    2011-01-01

    htmlabstractWe consider the following \\textsc{Tree-Constrained Bipartite Matching} problem: Given two rooted trees $T_1=(V_1,E_1)$, $T_2=(V_2,E_2)$ and a weight function $w: V_1\\times V_2 \\mapsto \\mathbb{R}_+$, find a maximum weight matching $\\mathcal{M}$ between nodes of the two trees, such that

  16. Fingerprint Matching Using Minutiae Quadruplets | Iloanusi ...

    African Journals Online (AJOL)

    Fingerprint matching faces several challenges resulting from the varying quality of fingerprint scanners, the weakness of some scanners in detecting fake fingerprints and the poor performance of fingerprint matching algorithms caused by the high intraclass variations between fingerprints of the same subject. The major ...

  17. Determination of Transmission Line Impedance Matching Parameters

    African Journals Online (AJOL)

    The analysis of measured and computed matching parameters show that the values obtained are within the acceptable standard threshold values of Voltage Standing Wave Ratio ≤1.50 and Return loss ≥ +14dB used by telecommunication transmission designers worldwide. Keywords: Impedance matching, voltage ...

  18. Monkeys Match and Tally Quantities across Senses

    Science.gov (United States)

    Jordan, Kerry E.; MacLean, Evan L.; Brannon, Elizabeth M.

    2008-01-01

    We report here that monkeys can actively match the number of sounds they hear to the number of shapes they see and present the first evidence that monkeys sum over sounds and sights. In Experiment 1, two monkeys were trained to choose a simultaneous array of 1-9 squares that numerically matched a sample sequence of shapes or sounds. Monkeys…

  19. Local Stereo Matching Using Adaptive Local Segmentation

    NARCIS (Netherlands)

    Damjanovic, S.; van der Heijden, Ferdinand; Spreeuwers, Lieuwe Jan

    We propose a new dense local stereo matching framework for gray-level images based on an adaptive local segmentation using a dynamic threshold. We define a new validity domain of the fronto-parallel assumption based on the local intensity variations in the 4-neighborhood of the matching pixel. The

  20. On solution concepts for matching games

    NARCIS (Netherlands)

    Biro, Peter; Kern, Walter; Paulusma, Daniël; Kratochvil, J.; Li, A.; Fiala, J.; Kolman, P.

    A matching game is a cooperative game $(N,v)$ defined on a graph $G = (N,E)$ with an edge weighting $\\omega : E \\to {\\Bbb R}_+$ . The player set is $N$ and the value of a coalition $S \\subseteq  N$ is defined as the maximum weight of a matching in the subgraph induced by $S$. First we present an

  1. String matching with variable length gaps

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Vildhøj, Hjalte Wedel

    2012-01-01

    We consider string matching with variable length gaps. Given a string T and a pattern P consisting of strings separated by variable length gaps (arbitrary strings of length in a specified range), the problem is to find all ending positions of substrings in T that match P. This problem is a basic...

  2. Design and operations of a load-tolerant external conjugate-T matching system for the A2 ICRH antennas at JET

    International Nuclear Information System (INIS)

    Monakhov, I.; Graham, M.; Blackman, T.; Dowson, S.; Durodie, F.; Jacquet, P.; Lehmann, J.; Mayoral, M.-L.; Nightingale, M.P.S.; Noble, C.; Sheikh, H.; Vrancken, M.; Walden, A.; Whitehurst, A.; Wooldridge, E.

    2013-01-01

    A load-tolerant external conjugate-T (ECT) impedance matching system for two A2 ion cyclotron resonance heating (ICRH) antennas was successfully put into operation at JET. The system allows continuous injection of the radio-frequency (RF) power into plasma in the presence of strong antenna loading perturbations caused by edge-localized modes (ELMs). Reliable ECT performance was demonstrated under a variety of antenna loading conditions including H-mode plasmas with radial outer gaps (ROGs) in the range 4–14 cm. The high resilience to ELMs predicted during the circuit simulations was fully confirmed experimentally. Dedicated arc-detection techniques and real-time matching algorithms were developed as a part of the ECT project. The new advanced wave amplitude comparison system has proven highly efficient in detection of arcs both between and during ELMs. The ECT system has allowed the delivery of up to 4 MW of RF power without trips into plasmas with type-I ELMs. Together with the 3 dB system and the ITER-like antenna, the ECT has brought the total RF power coupled to ELMy plasma to over 8 MW, considerably enhancing JET research capabilities. This paper provides an overview of the key design features of the ECT system and summarizes the main experimental results achieved so far. (paper)

  3. Analytic expressions for mode conversion in a plasma with a parabolic density profile: Generalized results

    International Nuclear Information System (INIS)

    Hinkel-Lipsker, D.E.; Fried, B.D.; Morales, G.J.

    1993-01-01

    This study provides an analytic solution to the general problem of mode conversion in an unmagnetized plasma. Specifically, an electromagnetic wave of frequency ω propagating through a plasma with a parabolic density profile of scale length L p is examined. The mode conversion points are located a distance Δ 0 from the peak of the profile, where the electron plasma frequency ω p (z) matches the wave frequency ω. The corresponding reflection, transmission, and mode conversion coefficients are expressed analytically in terms of parabolic cylinder functions for all values of Δ 0 . The method of solution is based on a source approximation technique that is valid when the electromagnetic and electrostatic scale lengths are well separated. For large Δ 0 , i.e., (cL p /ω) 1/2 much-lt Δ 0 p , the appropriately scaled result [D. E. Hinkel-Lipsker et al., Phys. Fluids B 4, 559 (1992)] for a linear density profile is recovered as the parabolic cylinder functions asymptotically become Airy functions. When Δ 0 →0, the special case of conversion at the peak of the profile [D. E. Hinkel-Lipsker et al., Phys. Fluids B 4, 1772 (1992)] is obtained

  4. Comparison of block matching and differential methods for motion analysis of the carotid artery wall from ultrasound images.

    Science.gov (United States)

    Golemati, Spyretta; Stoitsis, John S; Gastounioti, Aimilia; Dimopoulos, Alexandros C; Koropouli, Vassiliki; Nikita, Konstantina S

    2012-09-01

    Motion of the carotid artery wall is important for the quantification of arterial elasticity and contractility and can be estimated with a number of techniques. In this paper, a framework for quantitative evaluation of motion analysis techniques from B-mode ultrasound images is introduced. Six synthetic sequences were produced using 1) a real image corrupted by Gaussian and speckle noise of 25 and 15 dB, and 2) the ultrasound simulation package Field II. In both cases, a mathematical model was used, which simulated the motion of the arterial wall layers and the surrounding tissue, in the radial and longitudinal directions. The performance of four techniques, namely optical flow (OF (HS)), weighted least-squares optical flow (OF (LK(WLS))), block matching (BM), and affine block motion model (ABMM), was investigated in the context of this framework. The average warping indices were lowest for OF (LK(WLS)) (1.75 pixels), slightly higher for ABMM (2.01 pixels), and highest for BM (6.57 pixels) and OF (HS) (11.57 pixels). Due to its superior performance, OF (LK(WLS)) was used to quantify motion of selected regions of the arterial wall in real ultrasound image sequences of the carotid artery. Preliminary results indicate that OF (LK(WLS)) is promising, because it efficiently quantified radial, longitudinal, and shear strains in healthy adults and diseased subjects.

  5. Context-dependent logo matching and recognition.

    Science.gov (United States)

    Sahbi, Hichem; Ballan, Lamberto; Serra, Giuseppe; Del Bimbo, Alberto

    2013-03-01

    We contribute, through this paper, to the design of a novel variational framework able to match and recognize multiple instances of multiple reference logos in image archives. Reference logos and test images are seen as constellations of local features (interest points, regions, etc.) and matched by minimizing an energy function mixing: 1) a fidelity term that measures the quality of feature matching, 2) a neighborhood criterion that captures feature co-occurrence/geometry, and 3) a regularization term that controls the smoothness of the matching solution. We also introduce a detection/recognition procedure and study its theoretical consistency. Finally, we show the validity of our method through extensive experiments on the challenging MICC-Logos dataset. Our method overtakes, by 20%, baseline as well as state-of-the-art matching/recognition procedures.

  6. Matching Properties of Femtofarad and Sub-Femtofarad MOM Capacitors

    KAUST Repository

    Omran, Hesham

    2016-04-21

    Small metal-oxide-metal (MOM) capacitors are essential to energy-efficient mixed-signal integrated circuit design. However, only few reports discuss their matching properties based on large sets of measured data. In this paper, we report matching properties of femtofarad and sub-femtofarad MOM vertical-field parallel-plate capacitors and lateral-field fringing capacitors. We study the effect of both the finger-length and finger-spacing on the mismatch of lateral-field capacitors. In addition, we compare the matching properties and the area efficiency of vertical-field and lateral-field capacitors. We use direct mismatch measurement technique, and we illustrate its feasibility using experimental measurements and Monte Carlo simulations. The test-chips are fabricated in a 0.18 \\\\mutext{m} CMOS process. A large number of test structures is characterized (4800 test structures), which improves the statistical reliability of the extracted mismatch information. Despite conventional wisdom, extensive measurements show that vertical-field and lateral-field MOM capacitors have the same matching properties when the actual capacitor area is considered. Measurements show that the mismatch depends on the capacitor area but not on the spacing; thus, for a given mismatch specification, the lateral-field MOM capacitor can have arbitrarily small capacitance by increasing the spacing between the capacitor fingers, at the expense of increased chip area.

  7. Estimation of Initial Position Using Line Segment Matching in Maps

    Directory of Open Access Journals (Sweden)

    Chongyang Wei

    2016-06-01

    Full Text Available While navigating in a typical traffic scene, with a drastic drift or sudden jump in its Global Positioning System (GPS position, the localization based on such an initial position is unable to extract precise overlapping data from the prior map in order to match the current data, thus rendering the localization as unfeasible. In this paper, we first propose a new method to estimate an initial position by matching the infrared reflectivity maps. The maps consist of a highly precise prior map, built with the offline simultaneous localization and mapping (SLAM technique, and a smooth current map, built with the integral over velocities. Considering the attributes of the maps, we first propose to exploit the stable, rich line segments to match the lidar maps. To evaluate the consistency of the candidate line pairs in both maps, we propose to adopt the local appearance, pairwise geometric attribute and structural likelihood to construct an affinity graph, as well as employ a spectral algorithm to solve the graph efficiently. The initial position is obtained according to the relationship between the vehicle's current position and matched lines. Experiments on the campus with a GPS error of dozens of metres show that our algorithm can provide an accurate initial value with average longitudinal and lateral errors being 1.68m and 1.04m, respectively.

  8. Characterization of hidden modes in networks of superconducting qubits

    Science.gov (United States)

    Sheldon, Sarah; Sandberg, Martin; Paik, Hanhee; Abdo, Baleegh; Chow, Jerry M.; Steffen, Matthias; Gambetta, Jay M.

    2017-11-01

    We present a method for detecting electromagnetic (EM) modes that couple to a superconducting qubit in a circuit quantum electrodynamics architecture. Based on measurement-induced dephasing, this technique allows the measurement of modes that have a high quality factor (Q) and may be difficult to detect through standard transmission and reflection measurements at the device ports. In this scheme, the qubit itself acts as a sensitive phase meter, revealing modes that couple to it through measurements of its coherence time. Such modes are indistinguishable from EM modes that do not couple to the qubit using a vector network analyzer. Moreover, this technique provides useful characterization parameters including the quality factor and the coupling strength of the unwanted resonances. We demonstrate the method for detecting both high-Q coupling resonators in planar devices as well as spurious modes produced by a 3D cavity.

  9. Application of a matched filter approach for finite aperture transducers for the synthetic aperture imaging of defects.

    Science.gov (United States)

    Satyanarayan, L; Muralidharan, Ajith; Krishnamurthy, Chittivenkata; Balasubramaniam, Krishnan

    2010-06-01

    The suitability of the synthetic aperture imaging of defects using a matched filter approach on finite aperture transducers was investigated. The first part of the study involved the use a finite-difference time-domain (FDTD) algorithm to simulate the phased array ultrasonic wave propagation in an aluminum block and its interaction with side-drilled hole-like defects. B-scans were generated using the FDTD method for three active aperture transducer configurations of the phased array (a) single element and (b) 16-element linear scan mode, and (c) 16-element steering mode. A matched filter algorithm (MFA) was developed using the delay laws and the spatial impulse response of a finite size rectangular phased array transducer. The conventional synthetic aperture focusing technique (SAFT) algorithm and the MFA were independently applied on the FDTD signals simulated with the probe operating at a center frequency of 5 MHz and the processed B-scans were compared. The second part of the study investigated the capability of the MFA approach to improve the SNR. Gaussian white noise was added to the FDTD generated defect signals. The noisy B-scans were then processed using the SAFT and the MFA and the improvements in the SNR were estimated. The third part of the study investigated the application of the MFA to image and size surface-crack-like defects in pipe specimens obtained using a 45 degrees steered beam from a phased array probe. These studies confirm that MFA is an alternative to SAFT with little additional computational burden. It can also be applied blindly, like SAFT, to effect synthetic focusing with distinct advantages in treating finite transducer effects, and in handling steered beam inspections. Finally, limitations of the MFA in dealing with larger-sized transducers are discussed.

  10. Distortion analysis on binary representation of minutiae based fingerprint matching for match-on-card

    CSIR Research Space (South Africa)

    Mlambo, CS

    2016-12-01

    Full Text Available The fingerprint matching on the smart card has long been developed and recognized faster method than fingerprint matching on a computer or large capacity systems. There has been much research and activities concerned with improving the accuracy...

  11. PSOM2—partitioning-based scalable ontology matching using ...

    Indian Academy of Sciences (India)

    B Sathiya

    2017-11-16

    -based systems to reduce the matching space. ... reduction in execution time, leading to an effective and scalable ontology matching system. Keywords. ... ontology matching results, collaborative and social ontol- ogy matching ...

  12. Mode og mozzarella

    DEFF Research Database (Denmark)

    Nielsen, Jakob Isak

    2013-01-01

    Under en samtale i Paolo Sorrentinos La grande bellezza/da. Den store skønhed (2013) anføres det, at Italiens primære eksportvarer er mode og mozzarella. Selve filmen vidner om, at Italien har andet at byde på – heriblandt filmkunst og Roms righoldige kulturhistorie.......Under en samtale i Paolo Sorrentinos La grande bellezza/da. Den store skønhed (2013) anføres det, at Italiens primære eksportvarer er mode og mozzarella. Selve filmen vidner om, at Italien har andet at byde på – heriblandt filmkunst og Roms righoldige kulturhistorie....

  13. MDM: A Mode Diagram Modeling Framework

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    2012-12-01

    Full Text Available Periodic control systems used in spacecrafts and automotives are usually period-driven and can be decomposed into different modes with each mode representing a system state observed from outside. Such systems may also involve intensive computing in their modes. Despite the fact that such control systems are widely used in the above-mentioned safety-critical embedded domains, there is lack of domain-specific formal modelling languages for such systems in the relevant industry. To address this problem, we propose a formal visual modeling framework called mode diagram as a concise and precise way to specify and analyze such systems. To capture the temporal properties of periodic control systems, we provide, along with mode diagram, a property specification language based on interval logic for the description of concrete temporal requirements the engineers are concerned with. The statistical model checking technique can then be used to verify the mode diagram models against desired properties. To demonstrate the viability of our approach, we have applied our modelling framework to some real life case studies from industry and helped detect two design defects for some spacecraft control systems.

  14. A modal approach based on perfectly matched layers for the forced response of elastic open waveguides

    Science.gov (United States)

    Gallezot, M.; Treyssède, F.; Laguerre, L.

    2018-03-01

    This paper investigates the computation of the forced response of elastic open waveguides with a numerical modal approach based on perfectly matched layers (PML). With a PML of infinite thickness, the solution can theoretically be expanded as a discrete sum of trapped modes, a discrete sum of leaky modes and a continuous sum of radiation modes related to the PML branch cuts. Yet with numerical methods (e.g. finite elements), the waveguide cross-section is discretized and the PML must be truncated to a finite thickness. This truncation transforms the continuous sum into a discrete set of PML modes. To guarantee the uniqueness of the numerical solution of the forced response problem, an orthogonality relationship is proposed. This relationship is applicable to any type of modes (trapped, leaky and PML modes) and hence allows the numerical solution to be expanded on a discrete sum in a convenient manner. This also leads to an expression for the modal excitability valid for leaky modes. The physical relevance of each type of mode for the solution is clarified through two numerical test cases, a homogeneous medium and a circular bar waveguide example, excited by a point source. The former is favourably compared to a transient analytical solution, showing that PML modes reassemble the bulk wave contribution in a homogeneous medium. The latter shows that the PML mode contribution yields the long-term diffraction phenomenon whereas the leaky mode contribution prevails closer to the source. The leaky mode contribution is shown to remain accurate even with a relatively small PML thickness, hence reducing the computational cost. This is of particular interest for solving three-dimensional waveguide problems, involving two-dimensional cross-sections of arbitrary shapes. Such a problem is handled in a third numerical example by considering a buried square bar.

  15. A Landau fluid model for dissipative trapped electron modes

    International Nuclear Information System (INIS)

    Hedrick, C.L.; Leboeuf, J.N.; Sidikman, K.L.

    1995-09-01

    A Landau fluid model for dissipative trapped electron modes is developed which focuses on an improved description of the ion dynamics. The model is simple enough to allow nonlinear calculations with many harmonics for the times necessary to reach saturation. The model is motivated by a discussion that starts with the gyro-kinetic equation and emphasizes the importance of simultaneously including particular features of magnetic drift resonance, shear, and Landau effects. To ensure that these features are simultaneously incorporated in a Landau fluid model with only two evolution equations, a new approach to determining the closure coefficients is employed. The effect of this technique is to reduce the matching of fluid and kinetic responses to a single variable, rather than two, and to allow focusing on essential features of the fluctuations in question, rather than features that are only important for other types of fluctuations. Radially resolved nonlinear calculations of this model, advanced in time to reach saturation, are presented to partially illustrate its intended use. These calculations have a large number of poloidal and toroidal harmonics to represent the nonlinear dynamics in a converged steady state which includes cascading of energy to both short and long wavelengths

  16. Optical vortex propagation in few-mode rectangular polymer waveguides

    DEFF Research Database (Denmark)

    Lyubopytov, Vladimir S.; Chipouline, Arkadi; Zywietz, Urs

    2017-01-01

    We demonstrate that rectangular few-mode dielectric waveguides, fabricated with standard lithographic technique, can support on-chip propagation of optical vortices. We show that specific superpositions of waveguide eigenmodes form quasi-degenerate modes carrying light with high purity states of ...... of orbital angular momentum....

  17. Analysis of tokamak plasma confinement modes using the fast

    Indian Academy of Sciences (India)

    The Fourier analysis is a satisfactory technique for detecting plasma confinement modes in tokamaks. The confinement mode of tokamak plasma was analysed using the fast Fourier transformation (FFT). For this purpose, we used the data of Mirnov coils that is one of the identifying tools in the IR-T1 tokamak, with and ...

  18. Spatial light modulation for mode conditioning

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Palima, Darwin

    We demonstrate patented techniques for generating tuneable complex field distributions for controllable coupling to high-order guided modes of micro-structured fibres. The optical Fourier transform of binary phase-only patterns which are encoded on a computer-controlled spatial light modulator......, generates complex field distributions for selective launching of a desired mode. Both the amplitude and the phase of the programmable fields are modulated by straightforward and fast adjustments of simple pre-defined binary phase-only diffractive patterns. Experiments demonstrate tuneable coupling...

  19. Improving the Nephrology Match: the Path Forward.

    Science.gov (United States)

    Hsu, Chi-yuan; Parker, Mark G; Ross, Michael J; Schmidt, Rebecca J; Harris, Raymond C

    2015-11-01

    The Fellowship Match process was designed to provide applicants and program directors with an opportunity to consider all their options before making decisions about post-residency training. In a Match, applicants can choose the programs that best suit their career goals, and program directors can consider all candidates before preparing a rank order list. The Match is a contract, requiring obligations of both programs and applicants to achieve success, ensure uniformity, and standardize participation. Copyright © 2015 by the American Society of Nephrology.

  20. State of otolaryngology match: has competition increased since the "early" match?

    Science.gov (United States)

    Cabrera-Muffly, Cristina; Sheeder, Jeanelle; Abaza, Mona

    2015-05-01

    To examine fluctuations in supply and demand of otolaryngology residency positions after the shift from an "early match" coordinated by the San Francisco match to a "conventional" matching process through the National Residency Matching Program (NRMP). To determine whether competition among otolaryngology residency positions have changed during this time frame. Database analysis. Matching statistics from 1998 to 2013 were obtained for all first-year residency positions through the NRMP. Matching statistics from 1998 to 2005 were obtained for otolaryngology residency positions through the San Francisco match. Univariate analysis was performed, with a P value less than .05 determined as significant. The number of otolaryngology positions and applicants remained proportional to the overall number of positions and applicants in the NRMP match. Otolaryngology applicants per position and the matching rate of all applicants did not change between the 2 time periods studied. The overall match rate of US seniors applying to otolaryngology did not change, while the match rate of non-US seniors decreased significantly following initiation of the conventional match. There was no significant change in United States Medical Licensing Exam step 1 scores or percentage of unfilled otolaryngology residency positions between the 2 time periods. When comparing the early versus conventional otolaryngology match time periods, the only major change was the decreased percentage of matching among non-US senior applicants. Despite a significant shift in match timing after 2006, the supply, demand, and competitiveness of otolaryngology residency positions have not changed significantly. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  1. Dimerization of the Klenow fragment of Escherichia coli DNA polymerase I is linked to its mode of DNA binding.

    Science.gov (United States)

    Bailey, Michael F; Van der Schans, Edwin J C; Millar, David P

    2007-07-10

    Upon associating with a proofreading polymerase, the nascent 3' end of a DNA primer/template has two possible fates. Depending upon its suitability as a substrate for template-directed extension or postsynthetic repair, it will bind either to the 5'-3' polymerase active site, yielding a polymerizing complex, or to the 3'-5' exonuclease site, yielding an editing complex. In this investigation, we use a combination of biochemical and biophysical techniques to probe the stoichiometry, thermodynamic, and kinetic stability of the polymerizing and editing complexes. We use the Klenow fragment of Escherichia coli DNA polymerase I (KF) as a model proofreading polymerase and oligodeoxyribonucleotide primer/templates as model DNA substrates. Polymerizing complexes are produced by mixing KF with correctly base paired (matched) primer/templates, whereas editing complexes are produced by mixing KF with multiply mismatched primer/templates. Electrophoretic mobility shift titrations carried out with matched and multiply mismatched primer/templates give rise to markedly different electrophoretic patterns. In the case of the matched primer/template, the KF.DNA complex is represented by a slow moving band. However, in the case of the multiply mismatched primer/template, the complex is predominantly represented by a fast moving band. Analytical ultracentrifugation measurements indicate that the fast and slow moving bands correspond to 1:1 and 2:1 KF.DNA complexes, respectively. Fluorescence anisotropy titrations reveal that KF binds with a higher degree of cooperativity to the matched primer/template. Taken together, these results indicate that KF is able to dimerize on a DNA primer/template and that dimerization is favored when the first molecule is bound in the polymerizing mode, but disfavored when it is bound in the editing mode. We suggest that self-association of the polymerase may play an important and as yet unexplored role in coordinating high-fidelity DNA replication.

  2. Observaton of tunneling of slow and fast electromagnetic modes in coupled periodic waveguides

    DEFF Research Database (Denmark)

    Ha, Sangwoo; Sukhorukov, Andrey A.; Lavrinenko, Andrei

    2011-01-01

    We report the experimental observation of tunneling of slow and fast electromagnetic modes in coupled periodic waveguides shifted longitudinally by half of modulation period. According to the symmetry analysis, such a coupler supports two electromagnetic modes with exactly matched slow or fast gr...

  3. Theories and Modes

    Science.gov (United States)

    Apsche, Jack A.

    2005-01-01

    In his work on the Theory of Modes, Beck (1996) suggested that there were flaws with his cognitive theory. He suggested that though there are shortcomings to his cognitive theory, there were not similar shortcomings to the practice of Cognitive Therapy. The author suggests that if there are shortcomings to cognitive theory the same shortcomings…

  4. Thermodynamics of Radiation Modes

    Science.gov (United States)

    Pina, Eduardo; de la Selva, Sara Maria Teresa

    2010-01-01

    We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the…

  5. Magnetic modes in superlattices

    International Nuclear Information System (INIS)

    Oliveira, F.A.

    1990-04-01

    A first discussion of reciprocal propagation of magnetic modes in a superlattice is presented. In the absence of an applied external magnetic field a superllatice made of alternate layers of the type antiferromagnetic-non-magnetic materials presents effects similar to those of phonons in a dielectric superlattice. (A.C.A.S.) [pt

  6. Study Mode Negotiation.

    Science.gov (United States)

    Vasan, Mani Le; Sargunan, Rajeswary

    This paper outlines a model of study mode negotiation between clients and English Language Training providers that has been developed at the University of Malaya, specifically related to English language writing skills as taught to corporate clients. Negotiation is used to reach decisions concerning the goals and methodology of learning to ensure…

  7. Simplified laser frequency stabilization using spatial-mode interference

    Data.gov (United States)

    National Aeronautics and Space Administration — We will demonstrate a laser frequency stabilization technique based on spatial-mode interference that promises reductions in complexity, mass and power consumption...

  8. Discontinuous conduction mode analysis of phase-modulated series ...

    Indian Academy of Sciences (India)

    modulated dc–dc series resonant converter (SRC) operating in discontinuous conduction mode (DCM). The conventional fundamental harmonic approximation technique is extended for a non-ideal series resonant tank to clarify the limitations of ...

  9. Applications of the soft computing in the automated history matching

    Energy Technology Data Exchange (ETDEWEB)

    Silva, P.C.; Maschio, C.; Schiozer, D.J. [Unicamp (Brazil)

    2006-07-01

    Reservoir management is a research field in petroleum engineering that optimizes reservoir performance based on environmental, political, economic and technological criteria. Reservoir simulation is based on geological models that simulate fluid flow. Models must be constantly corrected to yield the observed production behaviour. The process of history matching is controlled by the comparison of production data, well test data and measured data from simulations. Parametrization, objective function analysis, sensitivity analysis and uncertainty analysis are important steps in history matching. One of the main challenges facing automated history matching is to develop algorithms that find the optimal solution in multidimensional search spaces. Optimization algorithms can be either global optimizers that work with noisy multi-modal functions, or local optimizers that cannot work with noisy multi-modal functions. The problem with global optimizers is the very large number of function calls, which is an inconvenience due to the long reservoir simulation time. For that reason, techniques such as least squared, thin plane spline, kriging and artificial neural networks (ANN) have been used as substitutes to reservoir simulators. This paper described the use of optimization algorithms to find optimal solution in automated history matching. Several ANN were used, including the generalized regression neural network, fuzzy system with subtractive clustering and radial basis network. The UNIPAR soft computing method was used along with a modified Hooke- Jeeves optimization method. Two case studies with synthetic and real reservoirs are examined. It was concluded that the combination of global and local optimization has the potential to improve the history matching process and that the use of substitute models can reduce computational efforts. 15 refs., 11 figs.

  10. An effective method of large scale ontology matching.

    Science.gov (United States)

    Diallo, Gayo

    2014-01-01

    We are currently facing a proliferation of heterogeneous biomedical data sources accessible through various knowledge-based applications. These data are annotated by increasingly extensive and widely disseminated knowledge organisation systems ranging from simple terminologies and structured vocabularies to formal ontologies. In order to solve the interoperability issue, which arises due to the heterogeneity of these ontologies, an alignment task is usually performed. However, while significant effort has been made to provide tools that automatically align small ontologies containing hundreds or thousands of entities, little attention has been paid to the matching of large sized ontologies in the life sciences domain. We have designed and implemented ServOMap, an effective method for large scale ontology matching. It is a fast and efficient high precision system able to perform matching of input ontologies containing hundreds of thousands of entities. The system, which was included in the 2012 and 2013 editions of the Ontology Alignment Evaluation Initiative campaign, performed very well. It was ranked among the top systems for the large ontologies matching. We proposed an approach for large scale ontology matching relying on Information Retrieval (IR) techniques and the combination of lexical and machine learning contextual similarity computing for the generation of candidate mappings. It is particularly adapted to the life sciences domain as many of the ontologies in this domain benefit from synonym terms taken from the Unified Medical Language System and that can be used by our IR strategy. The ServOMap system we implemented is able to deal with hundreds of thousands entities with an efficient computation time.

  11. Vector mode conversion based on tilted fiber Bragg grating in ring-core fibers

    Science.gov (United States)

    Mi, Yuean; Ren, Guobin; Gao, Yixiao; Li, Haisu; Zhu, Bofeng; Liu, Yu

    2018-03-01

    We propose a vector mode conversion approach based on tilted fiber Bragg grating (TFBG) written in ring-core fiber with effective separation of eigenmodes. The mode coupling properties of TFBG are numerically investigated. It is shown that under the constraint of phase matching, the conversion of high-order vector modes could be achieved at specific wavelengths. Moreover, the polarization of incident light and tilt angle of TFBG play critical roles in mode coupling process. The proposed TFBG provides an efficient method to realize high-order vector mode conversion, and it shows great potential for fibers based OAM beam generation and fiber lasers with vortex beams output.

  12. Experimental techniques; Techniques experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Roussel-Chomaz, P. [GANIL CNRS/IN2P3, CEA/DSM, 14 - Caen (France)

    2007-07-01

    This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, {gamma} detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)

  13. Shape-matching soft mechanical metamaterials

    NARCIS (Netherlands)

    Mirzaali Mazandarani, M.; Janbaz, S.; Strano, M.; Vergani, L.; Zadpoor, A.A.

    2018-01-01

    Architectured materials with rationally designed geometries could be used to create mechanical metamaterials with unprecedented or rare properties and functionalities. Here, we introduce "shape-matching" metamaterials where the geometry of cellular structures comprising auxetic and conventional

  14. Mobile Application for Pesticide Label Matching

    Science.gov (United States)

    The label matching application will give inspectors the ability to instantly compare pesticide product labels against state and federal label databases via their cell phone, tablet or other mobile device.

  15. Matched Spectral Filter Imager, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — OPTRA proposes the development of an imaging spectrometer for greenhouse gas and volcanic gas imaging based on matched spectral filtering and compressive imaging....

  16. The Effectiveness of Advertising Matching Purchase Motivation

    NARCIS (Netherlands)

    J. Loef; G. Antonides (Gerrit); W.F. van Raaij (Fred)

    2001-01-01

    textabstractSeveral authors have proposed frameworks to help advertisers predict and plan advertising effectiveness. Rossiter and Percy's advertising grid (1997) recommends that the ad appeal should match the purchase motivation or attitude base. They suggest that for utilitarian brands

  17. On Stable Marriages and Greedy Matchings

    Energy Technology Data Exchange (ETDEWEB)

    Manne, Fredrik; Naim, Md; Lerring, Hakon; Halappanavar, Mahantesh

    2016-12-11

    Research on stable marriage problems has a long and mathematically rigorous history, while that of exploiting greedy matchings in combinatorial scientific computing is a younger and less developed research field. In this paper we consider the relationships between these two areas. In particular we show that several problems related to computing greedy matchings can be formulated as stable marriage problems and as a consequence several recently proposed algorithms for computing greedy matchings are in fact special cases of well known algorithms for the stable marriage problem. However, in terms of implementations and practical scalable solutions on modern hardware, the greedy matching community has made considerable progress. We show that due to the strong relationship between these two fields many of these results are also applicable for solving stable marriage problems.

  18. Dataset Curation through Renders and Ontology Matching

    Science.gov (United States)

    2015-09-01

    Dataset Curation through Renders and Ontology Matching Yair Movshovitz-Attias CMU-CS-15-119 September 2015 School of Computer Science Computer...REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Dataset Curation through Renders and Ontology Matching 5a...mapped to an ontology of geographical entities, we are able to extract multiple relevant labels per image. For the viewpoint estimation problem, by

  19. A Theory of Rerepresentation in Analogical Matching

    Science.gov (United States)

    2003-01-01

    cause (higherPressure Beaker Vial) (flow Beaker Vial Water Pipe)) T2: (cause (hotterThan Coffee IceCube ) (flow Coffee IceCube ...Coffee IceCube ) from the earlier example requires rewriting both expressions in terms of a more general, dimensional-independent comparative (e.g...greaterThan (Temperature Coffee) (Temperature IceCube )) which will match because non-identical function matches are allowed by structure

  20. Technological progress and average job matching quality

    OpenAIRE

    Centeno, Mário; Corrêa, Márcio V.

    2009-01-01

    Our objective is to study, in a labor market characterized by search frictions, the effect of technological progress on the average quality of job matches. For that, we use an extension of Mortensen and Pissarides (1998) and obtain as results that the effects of technological progress on the labor market depend upon the initial conditions of the economy. If the economy is totally characterized by the presence of low-quality job matches, an increase in technological progress is accompanied by ...

  1. INFORMATION SYSTEMS AUDIT CURRICULA CONTENT MATCHING

    OpenAIRE

    Vasile-Daniel CARDOȘ; Ildikó Réka CARDOȘ

    2014-01-01

    Financial and internal auditors must cope with the challenge of performing their mission in technology enhanced environment. In this article we match the information technology description found in the International Federation of Accountants (IFAC) and the Institute of Internal Auditors (IIA) curricula against the Model Curriculum issued by the Information Systems Audit and Control Association (ISACA). By reviewing these three curricula, we matched the content in the ISACA Model Curriculum wi...

  2. 't Hooft anomaly matching for discrete symmetries

    International Nuclear Information System (INIS)

    Csaki, C.; Murayama, Hitoshi; Lawrence Berkeley National Lab., CA

    1998-05-01

    The authors show how to extend the 't Hooft anomaly matching conditions to discrete symmetries. They check these discrete anomally matching conditions on several proposed low-energy spectra of certain strongly interacting gauge theories. The excluded examples include the proposed chirally symmetric vacuum of pure N = 1 supersymmetric yang-Mills theories, certain non-supersymmetric confining theories and some self-dual N = 1 supersymmetric theories based on exceptional groups

  3. Rebate subsidies, matching subsidies and isolation effects

    Directory of Open Access Journals (Sweden)

    Douglas D. Davis

    2006-07-01

    Full Text Available In a series of recent experiments (Davis, Millner and Reilly, 2005, Eckel and Grossman, 2003, 2005a-c, 2006, matching subsidies generate significantly higher charity receipts than do theoretically equivalent rebate subsidies. This paper reports a laboratory experiment conducted to examine whether the higher receipts are attributable to a relative preference for matching subsidies or to an ``isolation effect'' (McCaffery and Baron, 2003, 2006. Some potential policy implications of isolation effects on charitable contributions are also

  4. Improved efficiency of CT interpretation using an automated lung nodule matching program.

    Science.gov (United States)

    Koo, Chi Wan; Anand, Vikram; Girvin, Francis; Wickstrom, Maj L; Fantauzzi, John P; Bogoni, Luca; Babb, James S; Ko, Jane P

    2012-07-01

    The purpose of this study was to assess the impact of an automated program on improvement in lung nodule matching efficiency. Four thoracic radiologists independently reviewed two serial chest CT examinations from each of 57 patients. Each radiologist performed timed manual lung nodule matching. After 6 weeks, all radiologists independently repeated the timed matching portion using an automated nodule matching program. The time required for manual and automated matching was compared. The impact of nodule size and number on matching efficiency was determined. An average of 325 (range, 244-413) noncalcified solid pulmonary nodules was identified. Nodule matching was significantly faster with the automated program irrespective of the interpreting radiologist (p 0.5). The automated program achieved 90%, 90%, 79%, and 92% accuracy for the four readers. The improvement in efficiency for a given patient using the automated technique was proportional to the number of matched nodules (p < 0.0001) and inversely proportional to nodule size (p < 0.05). Use of the automated lung nodule matching program significantly improves diagnostic efficiency. The time saved is proportionate to the number of nodules identified and inversely proportional to nodule size. Adoption of such a program should expedite CT examination interpretation and improve report turnaround time.

  5. Fast algorithms for approximate circular string matching.

    Science.gov (United States)

    Barton, Carl; Iliopoulos, Costas S; Pissis, Solon P

    2014-03-22

    Circular string matching is a problem which naturally arises in many biological contexts. It consists in finding all occurrences of the rotations of a pattern of length m in a text of length n. There exist optimal average-case algorithms for exact circular string matching. Approximate circular string matching is a rather undeveloped area. In this article, we present a suboptimal average-case algorithm for exact circular string matching requiring time O(n). Based on our solution for the exact case, we present two fast average-case algorithms for approximate circular string matching with k-mismatches, under the Hamming distance model, requiring time O(n) for moderate values of k, that is k=O(m/logm). We show how the same results can be easily obtained under the edit distance model. The presented algorithms are also implemented as library functions. Experimental results demonstrate that the functions provided in this library accelerate the computations by more than three orders of magnitude compared to a naïve approach. We present two fast average-case algorithms for approximate circular string matching with k-mismatches; and show that they also perform very well in practice. The importance of our contribution is underlined by the fact that the provided functions may be seamlessly integrated into any biological pipeline. The source code of the library is freely available at http://www.inf.kcl.ac.uk/research/projects/asmf/.

  6. Curbing - The Metallic Mode In-Between

    DEFF Research Database (Denmark)

    Aaen, Mathias; McGlashan, Julian; Sadolin, Cathrine

    2017-01-01

    Objectives This study aims to study the categorization Curbing from the pedagogical method Complete Vocal Technique as a reduced metallic mode compared with the full metallic modes Overdrive and Edge by means of audio perception, laryngostroboscopic imaging, acoustics, long-term average spectrum....... Curbing has a more open setting than Overdrive and Edge, with high visibility of the vocal folds, and the false folds giving a rectangular appearance. LTAS showed statistically significant differences between Curbing and the full metallic modes, with less energy across all spectra, yielding a high second...... is statistically significantly different from Overdrive and Edge, and can be categorized based on audio perception. This study demonstrates consistently different laryngeal gestures between Curbing and Overdrive and Edge, with high corresponding differences in LTAS, EGG and acoustic measures....

  7. MDM: A Mode Diagram Modeling Framework

    DEFF Research Database (Denmark)

    Wang, Zheng; Pu, Geguang; Li, Jianwen

    2012-01-01

    systems are widely used in the above-mentioned safety-critical embedded domains, there is lack of domain-specific formal modelling languages for such systems in the relevant industry. To address this problem, we propose a formal visual modeling framework called mode diagram as a concise and precise way...... to specify and analyze such systems. To capture the temporal properties of periodic control systems, we provide, along with mode diagram, a property specification language based on interval logic for the description of concrete temporal requirements the engineers are concerned with. The statistical model...... checking technique can then be used to verify the mode diagram models against desired properties. To demonstrate the viability of our approach, we have applied our modelling framework to some real life case studies from industry and helped detect two design defects for some spacecraft control systems....

  8. Observations on resistive wall modes

    International Nuclear Information System (INIS)

    Gerwin, R.A.; Finn, J.M.

    1996-01-01

    Several results on resistive wall modes and their application to tokamaks are presented. First, it is observed that in the presence of collisional parallel dynamics there is an exact cancellation to lowest order of the dissipative and sound wave effects for an ideal Ohm's law. This is easily traced to the fact that the parallel dynamics occurs along the perturbed magnetic field lines for such electromagnetic modes. Such a cancellation does not occur in the resistive layer of a tearing-like mode. The relevance to models for resistive wall modes using an electrostatic Hammett-Perkins type operator to model Landau damping will be discussed. Second, we observe that with an ideal Ohm's law, resistive wall modes can be destabilized by rotation in that part of parameter space in which the ideal MHD modes are stable with the wall at infinity. This effect can easily be explained by interpreting the resistive wall instability in terms of mode coupling between the backward stable MHD mode and a stable mode locked into the wall. Such an effect can occur for very small rotation for tearing-resistive wall modes in which inertia dominates viscosity in the layer, but the mode is stabilized by further rotation. For modes for which viscosity dominates in the layer, rotation is purely stabilizing. For both tearing models, a somewhat higher rotation frequency gives stability essentially whenever the tearing mode is stable with a perfectly conducting wall. These tearing/resistive wall results axe also simply explained in terms of mode coupling. It has been shown that resonant external ideal modes can be stabilized in the presence of resistive wall and resistive plasma with rotation of order the nominal tearing mode growth rate. We show that these modes behave as resistive wall tearing modes in the sense above. This strengthens the suggestion that rotational stabilization of the external kink with a resistive wall is due to the presence of resistive layers, even for ideal modes

  9. Capacity Enhancement of Few-Mode Fiber Transmission Systems Impaired by Mode-Dependent Loss

    Directory of Open Access Journals (Sweden)

    El-Mehdi Amhoud

    2018-02-01

    Full Text Available Space-division multiplexing over few-mode fibers is a promising solution to increase the capacity of the future generation of optical transmission systems. Mode-dependent loss (MDL is known to have a detrimental impact on the capacity of few-mode fiber systems. In the presence of MDL, spatial modes experience different attenuations which results in capacity reduction. In this work, we propose a digital signal processing solution and an optical solution to mitigate the impact of MDL and improve the channel capacity. First, we show that statistical channel state information can be used for a better power allocation for spatial modes instead of equal launch power to increase the system capacity. Afterwards, we propose a deterministic mode scrambling strategy to efficiently reduces the impact of MDL and improves few-mode fiber systems capacity. This scrambling strategy can be efficiently combined with the optimal power allocation to further enhance the capacity. Through numerical simulations of the average and outage capacities, we show that the proposed techniques bring significant capacity gains.

  10. Two-dimensional analysis of spurious modes in aluminum nitride film resonators.

    Science.gov (United States)

    Gong, Xun; Han, Min; Shang, Xiaoli; Xiong, Jun; Duan, Jie; Sekimoto, Hitoshi

    2007-06-01

    In this paper, a hybrid method, which combines the traditional concept of guided waves and the finite element method (FEM), is proposed to analyze the spurious modes of aluminum nitride (AIN) film with electrodes. First, the guided wave modes in the plated area are obtained by 1-D FEM. Second, a mode-match method is used to satisfy the boundary conditions. The vibration of the film resonator is a superposition of all of the guided modes. With respect to an A1N film resonator, which is a thickness-stretch mode resonator, we have identified three families of spurious modes: extension, thickness-stretch, and thickness-shear. The spectrum of spurious modes is calculated and the influence of the spurious modes is discussed.

  11. Quantitative analysis of error mode, error effect and criticality

    International Nuclear Information System (INIS)

    Li Pengcheng; Zhang Li; Xiao Dongsheng; Chen Guohua

    2009-01-01

    The quantitative method of human error mode, effect and criticality is developed in order to reach the ultimate goal of Probabilistic Safety Assessment. The criticality identification matrix of human error mode and task is built to identify the critical human error mode and task and the critical organizational root causes on the basis of the identification of human error probability, error effect probability and the criticality index of error effect. Therefore, this will be beneficial to take targeted measures to reduce and prevent the occurrence of critical human error mode and task. Finally, the application of the technique is explained through the application example. (authors)

  12. Affect-matching music improves cognitive performance in adults and young children for both positive and negative emotions

    OpenAIRE

    Franco, Fabia; Swaine, Joel S.; Israni, Shweta; Zaborowska, Katarzyna A.; Kaloko, Fatmata; Kesavarajan, Indu; Majek, Joseph A.

    2014-01-01

    Three experiments assessed the hypothesis that cognitive benefits associated with exposure to music only occur when the perceived emotion expression of the music and the participant’s affective state match. Experiment 1 revealed an affect-matching pattern modulated by gender when assessing high-arousal states of opposite valence (happy/angry) in an adult sample (n=94) in which mood classification was based on self-report, and affective valence in music was differentiated by mode and other exp...

  13. Block matching 3D random noise filtering for absorption optical projection tomography.

    Science.gov (United States)

    Fumene Feruglio, P; Vinegoni, C; Gros, J; Sbarbati, A; Weissleder, R

    2010-09-21

    Absorption and emission optical projection tomography (OPT), alternatively referred to as optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT), are recently developed three-dimensional imaging techniques with value for developmental biology and ex vivo gene expression studies. The techniques' principles are similar to the ones used for x-ray computed tomography and are based on the approximation of negligible light scattering in optically cleared samples. The optical clearing is achieved by a chemical procedure which aims at substituting the cellular fluids within the sample with a cell membranes' index matching solution. Once cleared the sample presents very low scattering and is then illuminated with a light collimated beam whose intensity is captured in transillumination mode by a CCD camera. Different projection images of the sample are subsequently obtained over a 360 degrees full rotation, and a standard backprojection algorithm can be used in a similar fashion as for x-ray tomography in order to obtain absorption maps. Because not all biological samples present significant absorption contrast, it is not always possible to obtain projections with a good signal-to-noise ratio, a condition necessary to achieve high-quality tomographic reconstructions. Such is the case for example, for early stage's embryos. In this work we demonstrate how, through the use of a random noise removal algorithm, the image quality of the reconstructions can be considerably improved even when the noise is strongly present in the acquired projections. Specifically, we implemented a block matching 3D (BM3D) filter applying it separately on each acquired transillumination projection before performing a complete three-dimensional tomographical reconstruction. To test the efficiency of the adopted filtering scheme, a phantom and a real biological sample were processed. In both cases, the BM3D filter led to a signal-to-noise ratio increment of

  14. Computation of resistive instabilities by matched asymptotic expansions

    Science.gov (United States)

    Glasser, A. H.; Wang, Z. R.; Park, J.-K.

    2016-11-01

    We present a method for determining the linear resistive magnetohydrodynamic (MHD) stability of an axisymmetric toroidal plasma, based on the method of matched asymptotic expansions. The plasma is partitioned into a set of ideal MHD outer regions, connected through resistive MHD inner regions about singular layers where q =m /n , with m and n toroidal mode numbers, respectively, and q the safety factor. The outer regions satisfy the ideal MHD equations with zero-frequency, which are identical to the Euler-Lagrange equations for minimizing the potential energy δW. The solutions to these equations go to infinity at the singular surfaces. The inner regions satisfy the equations of motion of resistive MHD with a finite eigenvalue, resolving the singularity. Both outer and inner regions are solved numerically by newly developed singular Galerkin methods, using specialized basis functions. These solutions are matched asymptotically, providing a complex dispersion relation which is solved for global eigenvalues and eigenfunctions in full toroidal geometry. The dispersion relation may have multiple complex unstable roots, which are found by advanced root-finding methods. These methods are much faster and more robust than the previous numerical methods. The new methods are applicable to more challenging high-pressure and strongly shaped plasma equilibria and generalizable to more realistic inner region dynamics. In the thermonuclear regime, where the outer and inner regions overlap, they are also much faster and more accurate than the straight-through methods, which treat the resistive MHD equations in the whole plasma volume.

  15. Evolution of reactor control modes

    International Nuclear Information System (INIS)

    Mourlevat, J.L.

    2007-01-01

    The article reviews the different reactor control modes: mode A, mode G and mode X that are used in PWR reactors designed by Areva. The purpose of reactor controlling is to compensate reactivity effects (xenon poisoning and counter-reaction effects) generated by load changes. A control mode is the strategy followed by using both soluble boron and the control rods to handle these reactivity effects. Soluble boron plays an important role in mode A but is less efficiency toward the end-of-cycle. Generally soluble boron is used to compensate slow reactivity effects. Mode G is based on the optimization of the use of the control rods and allows a quick return to the nominal power. Mode X combines the uses of control rods and soluble boron to cope with the operator's wishes: sparing effluents or having a quick return to nominal power. The mode X appears to be more penalizing concerning the fuel-cladding interaction. (A.C.)

  16. Sliding mode control the delta-sigma modulation approach

    CERN Document Server

    Sira-Ramírez, Hebertt

    2015-01-01

    This monograph presents a novel method of sliding mode control for switch-regulated nonlinear systems. The Delta Sigma modulation approach allows one to implement a continuous control scheme using one or multiple, independent switches, thus effectively merging the available linear and nonlinear controller design techniques with sliding mode control.   Sliding Mode Control: The Delta-Sigma Modulation Approach, combines rigorous mathematical derivation of the unique features of Sliding Mode Control and Delta-Sigma modulation with numerous illustrative examples from diverse areas of engineering. In addition, engineering case studies demonstrate the applicability of the technique and the ease with which one can implement the exposed results. This book will appeal to researchers in control engineering and can be used as graduate-level textbook for a first course on sliding mode control.

  17. Further Development of Rotating Rake Mode Measurement Data Analysis

    Science.gov (United States)

    Dahl, Milo D.; Hixon, Ray; Sutliff, Daniel L.

    2013-01-01

    The Rotating Rake mode measurement system was designed to measure acoustic duct modes generated by a fan stage. After analysis of the measured data, the mode amplitudes and phases were quantified. For low-speed fans within axisymmetric ducts, mode power levels computed from rotating rake measured data would agree with the far-field power levels on a tone by tone basis. However, this agreement required that the sound from the noise sources within the duct propagated outward from the duct exit without reflection at the exit and previous studies suggested conditions could exist where significant reflections could occur. To directly measure the modes propagating in both directions within a duct, a second rake was mounted to the rotating system with an offset in both the axial and the azimuthal directions. The rotating rake data analysis technique was extended to include the data measured by the second rake. The analysis resulted in a set of circumferential mode levels at each of the two rake microphone locations. Radial basis functions were then least-squares fit to this data to obtain the radial mode amplitudes for the modes propagating in both directions within the duct. The fit equations were also modified to allow evanescent mode amplitudes to be computed. This extension of the rotating rake data analysis technique was tested using simulated data, numerical code produced data, and preliminary in-duct measured data.

  18. ENRICHMENT OF ENSEMBLE LEARNING USING K-MODES RANDOM SAMPLING

    Directory of Open Access Journals (Sweden)

    Balamurugan Mahalingam

    2017-10-01

    Full Text Available Ensemble of classifiers combines the more than one prediction models of classifiers into single model for classifying the new instances. Unbiased samples could help the ensemble classifiers to build the efficient prediction model. Existing sampling techniques fails to give the unbiased samples. To overcome this problem, the paper introduces a k-modes random sample technique which combines the k-modes cluster algorithm and simple random sampling technique to take the sample from the dataset. In this paper, the impact of random sampling technique in the Ensemble learning algorithm is shown. Random selection was done properly by using k-modes random sampling technique. Hence, sample will reflect the characteristics of entire dataset.

  19. Matching mechanism analysis on an adaptive cycle engine

    Directory of Open Access Journals (Sweden)

    Junchao Zheng

    2017-04-01

    Full Text Available As a novel aero-engine concept, adaptive cycle aero-engines (ACEs are attracting wide attention in the international aviation industry due to their potential superior task adaptability along a wide flight regime. However, this superior task adaptability can only be demonstrated through proper combined engine control schedule design. It has resulted in an urgent need to investigate the effect of each variable geometry modulation on engine performance and stability. Thus, the aim of this paper is to predict and discuss the effect of each variable geometry modulation on the matching relationship between engine components as well as the overall engine performance at different operating modes, on the basis of a newly developed nonlinear component-based ACE performance model. Results show that at all four working modes, turning down the high pressure compressor variable stator vane, the low pressure turbine variable nozzle, the nozzle throat area, and turning up the core-driven fan stage variable stator vane, the high pressure turbine variable nozzle can increase the thrust at the expense of a higher high pressure turbine inlet total temperature. However, the influences of these adjustments on the trends of various engine components’ working points and working lines as well as the ratio of the rotation speed difference are different from each other. The above results provide valuable guidance and advice for engine combined control schedule design.

  20. Study of chromatic adaptation using memory color matches, Part I: neutral illuminants

    OpenAIRE

    Smet, Kevin A.G.; Zhai, Qiyan; Luo, Ming R.; Hanselaer, Peter

    2017-01-01

    Twelve corresponding color data sets have been obtained using the long-term memory colors of familiar objects as target stimuli. Data were collected for familiar objects with neutral, red, yellow, green and blue hues under 4 approximately neutral illumination conditions on or near the blackbody locus. The advantages of the memory color matching method are discussed in light of other more traditional asymmetric matching techniques. Results were compared to eight corresponding color data sets a...

  1. Length-Bounded Hybrid CPU/GPU Pattern Matching Algorithm for Deep Packet Inspection

    OpenAIRE

    Yi-Shan Lin; Chun-Liang Lee; Yaw-Chung Chen

    2017-01-01

    Since frequent communication between applications takes place in high speed networks, deep packet inspection (DPI) plays an important role in the network application awareness. The signature-based network intrusion detection system (NIDS) contains a DPI technique that examines the incoming packet payloads by employing a pattern matching algorithm that dominates the overall inspection performance. Existing studies focused on implementing efficient pattern matching algorithms by parallel progra...

  2. Optimally matching support and perceived spousal sensitivity.

    Science.gov (United States)

    Cutrona, Carolyn E; Shaffer, Philip A; Wesner, Kristin A; Gardner, Kelli A

    2007-12-01

    Partner sensitivity is an important antecedent of both intimacy (H. T. Reis & P. Shaver, 1988) and attachment (M. D. S. Ainsworth, 1989). On the basis of the optimal matching model of social support (C. E. Cutrona & D. Russell, 1990), support behaviors that "matched" the support goals of the stressed individual were predicted to lead to the perception of partner sensitivity. Predictions were tested with 59 married couples, who engaged in a videotaped self-disclosure task. Matching support was defined as the disclosure of emotions followed by emotional support or a request for information followed by informational support. Partial evidence was found for the predictions. Matching support following the disclosure of emotions was predictive of perceived partner sensitivity. Mismatched support following the disclosure of emotions predicted lower marital satisfaction, through the mediation of partner sensitivity. Matching support following a request for information was not predictive of perceived partner sensitivity, but negative partner responses (e.g., criticism or sarcasm) following a request for information negatively predicted perceptions of partner sensitivity. The importance of considering the context of support transactions is discussed.

  3. A robust line extraction and matching algorithm

    Science.gov (United States)

    Hussien, B.; Sridhar, B.

    1993-01-01

    This paper presents an algorithm for extracting straight lines from intensity mages and describes a line matching algorithm for solving the line correspondence problem. The line extraction process begins by detecting edges in the intensity image. Next, line support regions are formed where image points (pixels) have similar gradient orientation. A line fitting algorithm is then used to fit a line to the points in the line support region based on a least means square fitting algorithm. Finally, line segments are linked together to form the final lines by using an adaptive line linking method; this results in much stronger lines and a smaller set of lines to be considered. Once the lines are detected in a sequence of images, a line matching algorithm is used to match lines in one image to the lines in the other image. The images are either from a motion or stereo sequence. The matched lines may then be used with the sensor position and orientation data to estimate range to objects corresponding to the lines. We present results based on applying the line extraction and line matching algorithms to a synthetic image and an outdoor scene captured by a camera on a helicopter.

  4. Match Analysis in Volleyball: a systematic review

    Directory of Open Access Journals (Sweden)

    Miguel Silva

    2016-03-01

    Full Text Available The present article aims to review the available literature on match analysis in adult male Volleyball. Specific key words "performance analysis", "match analysis", "game analysis", "notational analysis", "tactical analysis", "technical analysis", "outcome" and "skills" were used to search relevant databases (PubMed, Web of Science, SportDiscus, Academic Search Complete and the International Journal of Performance Analysis in Sport. The research was conducted according to PRISMA (Preferred Reporting Items for Systematic reviews and Meta analyses guidelines. Of 3407 studies initially identified, only 34 were fully reviewed, and their outcome measures extracted and analyzed. Studies that fit all inclusion criteria were organized into two levels of analysis, according to their research design (comparative or predictive and depending on the type of variables analyzed (skills and their relationship with success, play position and match phase. Results show that from a methodological point of view, comparative studies where currently complemented with some predictive studies. This predictive approach emerged with the aim to identify the relationship between variables, considering their possible interactions and consequently its effect on team performance, contributing to a better understanding of Volleyball game performance through match analysis. Taking into account the limitations of the reviewed studies, future research should provide comprehensive operational definitions for the studied variables, using more recent samples, and consider integrating the player positions and match phase contexts into the analysis of Volleyball.

  5. PREDICTING THE MATCH OUTCOME IN ONE DAY INTERNATIONAL CRICKET MATCHES, WHILE THE GAME IS IN PROGRESS

    Directory of Open Access Journals (Sweden)

    Michael Bailey

    2006-12-01

    Full Text Available Millions of dollars are wagered on the outcome of one day international (ODI cricket matches, with a large percentage of bets occurring after the game has commenced. Using match information gathered from all 2200 ODI matches played prior to January 2005, a range of variables that could independently explain statistically significant proportions of variation associated with the predicted run totals and match outcomes were created. Such variables include home ground advantage, past performances, match experience, performance at the specific venue, performance against the specific opposition, experience at the specific venue and current form. Using a multiple linear regression model, prediction variables were numerically weighted according to statistical significance and used to predict the match outcome. With the use of the Duckworth-Lewis method to determine resources remaining, at the end of each completed over, the predicted run total of the batting team could be updated to provide a more accurate prediction of the match outcome. By applying this prediction approach to a holdout sample of matches, the efficiency of the "in the run" wagering market could be assessed. Preliminary results suggest that the market is prone to overreact to events occurring throughout the course of the match, thus creating brief inefficiencies in the wagering market

  6. Intrinsic localized modes and nonlinear impurity modes in curved ...

    Indian Academy of Sciences (India)

    structure of the localized modes induced by an isotopic light-mass impurity in this chain. We further demonstrate that a ... direct physical meaning and can describe polymers and biomolecular systems. The motion of the chain is confined to .... mode center (n = 0) the local mode must obey the expression (10). Equation (8).

  7. Mode-to-mode energy transfers in convective patterns

    Indian Academy of Sciences (India)

    Abstract. We investigate the energy transfer between various Fourier modes in a low- dimensional model for thermal convection. We have used the formalism of mode-to-mode energy transfer rate in our calculation. The evolution equations derived using this scheme is the same as those derived using the hydrodynamical ...

  8. Covariant diagrams for one-loop matching

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhengkang [Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2016-10-15

    We present a diagrammatic formulation of recently-revived covariant functional approaches to one-loop matching from an ultraviolet (UV) theory to a low-energy effective field theory. Various terms following from a covariant derivative expansion (CDE) are represented by diagrams which, unlike conventional Feynman diagrams, involve gaugecovariant quantities and are thus dubbed ''covariant diagrams.'' The use of covariant diagrams helps organize and simplify one-loop matching calculations, which we illustrate with examples. Of particular interest is the derivation of UV model-independent universal results, which reduce matching calculations of specific UV models to applications of master formulas. We show how such derivation can be done in a more concise manner than the previous literature, and discuss how additional structures that are not directly captured by existing universal results, including mixed heavy-light loops, open covariant derivatives, and mixed statistics, can be easily accounted for.

  9. Shape-matching soft mechanical metamaterials.

    Science.gov (United States)

    Mirzaali, M J; Janbaz, S; Strano, M; Vergani, L; Zadpoor, A A

    2018-01-17

    Architectured materials with rationally designed geometries could be used to create mechanical metamaterials with unprecedented or rare properties and functionalities. Here, we introduce "shape-matching" metamaterials where the geometry of cellular structures comprising auxetic and conventional unit cells is designed so as to achieve a pre-defined shape upon deformation. We used computational models to forward-map the space of planar shapes to the space of geometrical designs. The validity of the underlying computational models was first demonstrated by comparing their predictions with experimental observations on specimens fabricated with indirect additive manufacturing. The forward-maps were then used to devise the geometry of cellular structures that approximate the arbitrary shapes described by random Fourier's series. Finally, we show that the presented metamaterials could match the contours of three real objects including a scapula model, a pumpkin, and a Delft Blue pottery piece. Shape-matching materials have potential applications in soft robotics and wearable (medical) devices.

  10. INFORMATION SYSTEMS AUDIT CURRICULA CONTENT MATCHING

    Directory of Open Access Journals (Sweden)

    Vasile-Daniel CARDOȘ

    2014-11-01

    Full Text Available Financial and internal auditors must cope with the challenge of performing their mission in technology enhanced environment. In this article we match the information technology description found in the International Federation of Accountants (IFAC and the Institute of Internal Auditors (IIA curricula against the Model Curriculum issued by the Information Systems Audit and Control Association (ISACA. By reviewing these three curricula, we matched the content in the ISACA Model Curriculum with the IFAC International Education Practice Statement 2 and the IIAs’ Global Model Internal Audit Curriculum. In the IFAC and IIA Curriculum there are 16 content elements, out of 19 possible, which match, in their description, the ISACA Model Curriculum’s content. We noticed that a candidate who graduates an IFAC or IIA compliant program acquire IS auditing competences similar to the specific content of the ISACA model curriculum but less than the requirements for a professional information systems auditor.

  11. Improved Stereo Matching With Boosting Method

    Directory of Open Access Journals (Sweden)

    Shiny B

    2015-06-01

    Full Text Available Abstract This paper presents an approach based on classification for improving the accuracy of stereo matching methods. We propose this method for occlusion handling. This work employs classification of pixels for finding the erroneous disparity values. Due to the wide applications of disparity map in 3D television medical imaging etc the accuracy of disparity map has high significance. An initial disparity map is obtained using local or global stereo matching methods from the input stereo image pair. The various features for classification are computed from the input stereo image pair and the obtained disparity map. Then the computed feature vector is used for classification of pixels by using GentleBoost as the classification method. The erroneous disparity values in the disparity map found by classification are corrected through a completion stage or filling stage. A performance evaluation of stereo matching using AdaBoostM1 RUSBoost Neural networks and GentleBoost is performed.

  12. Matching in the Pi-Calculus

    Directory of Open Access Journals (Sweden)

    Kirstin Peters

    2014-08-01

    Full Text Available We study whether, in the pi-calculus, the match prefix—a conditional operator testing two names for (syntactic equality—is expressible via the other operators. Previously, Carbone and Maffeis proved that matching is not expressible this way under rather strong requirements (preservation and reflection of observables. Later on, Gorla developed a by now widely-tested set of criteria for encodings that allows much more freedom (e.g. instead of direct translations of observables it allows comparison of calculi with respect to reachability of successful states. In this paper, we offer a considerably stronger separation result on the non-expressibility of matching using only Gorla's relaxed requirements.

  13. Performance Evaluation of Tree Object Matching

    DEFF Research Database (Denmark)

    Somchaipeng, Kerawit; Sporring, Jon; Kreiborg, Sven

    2005-01-01

    of the algorithm is presented: an exact and an approximation. Several experiments are conducted to empirically evaluate the MSST matching algorithm under image distortions. Further, the performance of the MSST matching algorithm is measured on three databases: the ORL face database, magazine covers, and the COIL......Multi-Scale Singularity Trees (MSSTs) represents the deep structure of images in scale-space and provide both the connections between image features at different scales and their strengths. In this report we present and evaluate an algorithm that exploits the MSSTs for image matching. Two versions...... database. Finally the performance is compared with algorithms based on the Scale Invariant Feature Transform (SIFT), and the Position of Catastrophes (CAT)....

  14. Surface Area Distribution Descriptor for object matching

    Directory of Open Access Journals (Sweden)

    Mohamed F. Gafar

    2010-07-01

    Full Text Available Matching 3D objects by their similarity is a fundamental problem in computer vision, computer graphics and many other fields. The main challenge in object matching is to find a suitable shape representation that can be used to accurately and quickly discriminate between similar and dissimilar shapes. In this paper we present a new volumetric descriptor to represent 3D objects. The proposed descriptor is used to match objects under rigid transformations including uniform scaling. The descriptor represents the object by dividing it into shells, acquiring the area distribution of the object through those shells. The computed areas are normalised to make the descriptor scale-invariant in addition to rotation and translation invariant. The effectiveness and stability of the proposed descriptor to noise and variant sampling density as well as the effectiveness of the similarity measures are analysed and demonstrated through experimental results.

  15. A medium resolution fingerprint matching system

    Directory of Open Access Journals (Sweden)

    Ayman Mohammad Bahaa-Eldin

    2013-09-01

    Full Text Available In this paper, a novel minutiae based fingerprint matching system is proposed. The system is suitable for medium resolution fingerprint images obtained by low cost commercial sensors. The paper presents a new thinning algorithm, a new features extraction and representation, and a novel feature distance matching algorithm. The proposed system is rotation and translation invariant and is suitable for complete or partial fingerprint matching. The proposed algorithms are optimized to be executed on low resource environments both in CPU power and memory space. The system was evaluated using a standard fingerprint dataset and good performance and accuracy were achieved under certain image quality requirements. In addition, the proposed system was compared favorably to that of the state of the art systems.

  16. 76 FR 5235 - Privacy Act of 1974, as Amended; Computer Matching Program (SSA Internal Match)-Match Number 1014

    Science.gov (United States)

    2011-01-28

    ... which we will compare our current employee records of the Federal Personnel/Payroll System with the... computerized comparison of records. We will use this information to verify self-certification statements of... Matching Program We will compare identifying information from The Payroll, Leave and Attendance Records (60...

  17. A Matched Filter For Communicating With Chaos

    Science.gov (United States)

    Corron, Ned J.; Blakely, Jonathan N.

    2011-04-01

    In conventional communication systems, a matched filter provides optimal receiver performance in the presence of noise. As such, matched filters are highly desirable, yet they are practical only when a relatively small number of known basis functions are used to represent information. For communications using chaotic waveforms, the unpredictable and nonrepeating nature of chaos suggests the basis functions are uncertain and ever changing, which would preclude the use of a simple matched filter. Consequently, it is widely accepted that the performance of chaos communications lags that of conventional, no chaotic systems. In this paper, we show this assumption is not necessarily true. We describe a simple, low-dimensional chaotic oscillator that admits an exact analytic solution containing a single fixed basis function. The solution is written as the linear convolution of a symbol sequence and the basis function, similar to how conventional communications waveforms are usually represented. Despite the linear nature of the solution, waveform returns sampled at regular switching times are conjugate to a shift map, proving the oscillator is chaotic. A matched filter for the basis function is defined and used to extract symbolic information from the chaotic wave-form. Its performance in additive white Gaussian noise is comparable to that of binary phase-shift keying (BPSK). The oscillator and its matched filter have potential application in Hayes-type chaos communications where a message signal is encoded in the symbolic dynamics via small perturbation control. The discovery of a practical matched filter for chaos finally provides a coherent receiver to complement this elegant encoding scheme.

  18. Azimuthal decomposition of optical modes

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2012-07-01

    Full Text Available This presentation analyses the azimuthal decomposition of optical modes. Decomposition of azimuthal modes need two steps, namely generation and decomposition. An azimuthally-varying phase (bounded by a ring-slit) placed in the spatial frequency...

  19. Using Multi Resolution Census and Ranklet Transformation in Long Base Line SAR Image Matching

    Science.gov (United States)

    Ghannadi, M. A.; Saadat Seresht, M.; Motagh, M.; Eftekhari, A.

    2013-09-01

    Stereo radargrammetry is a mature technique for deriving height information from SAR image pairs. Generally height derived method by Radargrammetry consists of two stages: Images matching and space intersection. In this paper we propose a multi-step image matching algorithm founded on feature based matching. In this multi step algorithm, a SAR image is firstly filtered by a speckle suppression algorithm. a SIFT (Scale invariant feature transform) is used to extract feature points. Then we use non parametric Transformation as discriptor for the points extracted. Matching is sometimes more efficient when operating on image signals that have been transformed in some way, rather than operating on the pure intensity values themselves; In this article we use a pair of spotlight long base line TerraSAR-X images from JAM (IRAN). In a part with 700 × 700 pixels of these images 90 points are matched with using Ranklet algorithm. The mean absolute error of the corresponding points is 0.9 pixel. This match points number is 49 points with using multi resolution Census. The result shows that our proposed multi step image matching is superior to the Most FBM methods in terms of accuracy and number of matched points.

  20. USING MULTI RESOLUTION CENSUS AND RANKLET TRANSFORMATION IN LONG BASE LINE SAR IMAGE MATCHING

    Directory of Open Access Journals (Sweden)

    M. A. Ghannadi

    2013-09-01

    Full Text Available Stereo radargrammetry is a mature technique for deriving height information from SAR image pairs. Generally height derived method by Radargrammetry consists of two stages: Images matching and space intersection. In this paper we propose a multi-step image matching algorithm founded on feature based matching. In this multi step algorithm, a SAR image is firstly filtered by a speckle suppression algorithm. a SIFT (Scale invariant feature transform is used to extract feature points. Then we use non parametric Transformation as discriptor for the points extracted. Matching is sometimes more efficient when operating on image signals that have been transformed in some way, rather than operating on the pure intensity values themselves; In this article we use a pair of spotlight long base line TerraSAR-X images from JAM (IRAN. In a part with 700 × 700 pixels of these images 90 points are matched with using Ranklet algorithm. The mean absolute error of the corresponding points is 0.9 pixel. This match points number is 49 points with using multi resolution Census. The result shows that our proposed multi step image matching is superior to the Most FBM methods in terms of accuracy and number of matched points.

  1. Faster and Simpler Approximation of Stable Matchings

    Directory of Open Access Journals (Sweden)

    Katarzyna Paluch

    2014-04-01

    Full Text Available We give a 3 2 -approximation algorithm for finding stable matchings that runs in O(m time. The previous most well-known algorithm, by McDermid, has the same approximation ratio but runs in O(n3/2m time, where n denotes the number of people andm is the total length of the preference lists in a given instance. In addition, the algorithm and the analysis are much simpler. We also give the extension of the algorithm for computing stable many-to-many matchings.

  2. History Matching: Towards Geologically Reasonable Models

    DEFF Research Database (Denmark)

    Melnikova, Yulia; Cordua, Knud Skou; Mosegaard, Klaus

    that measures similarity between statistics of a training image and statistics of any smooth model is introduced and its analytical gradient is computed. This allows us to apply any gradientbased method to history matching problem and guide a solution until it satisfies both production data and complexity......This work focuses on the development of a new method for history matching problem that through a deterministic search finds a geologically feasible solution. Complex geology is taken into account evaluating multiple point statistics from earth model prototypes - training images. Further a function...

  3. Adiabatic matching section for plasma accelerated beams

    Directory of Open Access Journals (Sweden)

    Klaus Floettmann

    2014-05-01

    Full Text Available An adiabatic matching section is discussed as option to control the divergence and emittance growth of a beam exiting a plasma channel. Based on a general analytical solution of a focusing channel with varying focusing strength, a focusing profile is proposed which allows for a fast expansion of the beam size while keeping the emittance growth minimal. The solution is also applicable to other cases, e.g., the matching of a positron source to the downstream accelerating section, which are, however, not discussed in this contribution.

  4. Different modes of engagement

    DEFF Research Database (Denmark)

    Nickelsen, Niels Christian Mossfeldt

    of values from core participants, such as the disabled, the care assistants and the producer. This leads to a discussion of different modes of engagement focusing on the overall questions: To what extend are usage scenarios pre-scripted by the FAR? Taking STS as an analytic resource, this leads...... to a discussion of what the FAR is supposed to attend to and what implications that leads to. What knowledge of the sensible world is for instance inscripted into the FAR and how do different parties take this up? What do we learn about our own (in)sensibilities when we examine the design and use of feeding...

  5. Quasinormal modes and holography

    Science.gov (United States)

    Kovtun, Pavel K.; Starinets, Andrei O.

    2005-10-01

    Quasinormal frequencies of electromagnetic and gravitational perturbations in asymptotically anti-de Sitter spacetime can be identified with poles of the corresponding real-time Green’s functions in a holographically dual finite temperature field theory. The quasinormal modes are defined for gauge-invariant quantities which obey an incoming-wave boundary condition at the horizon and a Dirichlet condition at the boundary. As an application, we explicitly find poles of retarded correlation functions of R-symmetry currents and the energy-momentum tensor in strongly coupled finite temperature N=4 supersymmetric SU(Nc) Yang-Mills theory in the limit of large Nc.

  6. Localized Acoustic Surface Modes

    KAUST Repository

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  7. Cauchy-perturbative matching reexamined: Tests in spherical symmetry

    International Nuclear Information System (INIS)

    Zink, Burkhard; Pazos, Enrique; Diener, Peter; Tiglio, Manuel

    2006-01-01

    During the last few years progress has been made on several fronts making it possible to revisit Cauchy-perturbative matching (CPM) in numerical relativity in a more robust and accurate way. This paper is the first in a series where we plan to analyze CPM in the light of these new results. One of the new developments is an understanding of how to impose constraint-preserving boundary conditions (CPBC); though most of the related research has been driven by outer boundaries, one can use them for matching interface boundaries as well. Another front is related to numerically stable evolutions using multiple patches, which in the context of CPM allows the matching to be performed on a spherical surface, thus avoiding interpolations between Cartesian and spherical grids. One way of achieving stability for such schemes of arbitrary high order is through the use of penalty techniques and discrete derivatives satisfying summation by parts (SBP). Recently, new, very efficient and high-order accurate derivatives satisfying SBP and associated dissipation operators have been constructed. Here we start by testing all these techniques applied to CPM in a setting that is simple enough to study all the ingredients in great detail: Einstein's equations in spherical symmetry, describing a black hole coupled to a massless scalar field. We show that with the techniques described above, the errors introduced by Cauchy-perturbative matching are very small, and that very long-term and accurate CPM evolutions can be achieved. Our tests include the accretion and ring-down phase of a Schwarzschild black hole with CPM, where we find that the discrete evolution introduces, with a low spatial resolution of Δr=M/10, an error of 0.3% after an evolution time of 1,000,000M. For a black hole of solar mass, this corresponds to approximately 5s, and is therefore at the lower end of timescales discussed e.g. in the collapsar model of gamma-ray burst engines

  8. Raman amplification of OAM modes

    DEFF Research Database (Denmark)

    Ingerslev, Kasper; Gregg, Patrick; Galili, Michael

    2017-01-01

    The set of fibre modes carrying orbital angular momentum (OAM) is a possible basis for mode division multiplexing. In this regard, fibres supporting OAM modes have been fabricated [1], and optical communication using these fibres, has been demonstrated [2]. A vital part of any long range...

  9. ACCA College English Teaching Mode

    Science.gov (United States)

    Ding, Renlun

    2008-01-01

    This paper elucidates a new college English teaching mode--"ACCA" (Autonomous Cooperative Class-teaching All-round College English Teaching Mode). Integrated theories such as autonomous learning and cooperative learning into one teaching mode, "ACCA", which is being developed and advanced in practice as well, is the achievement…

  10. Fluxon modes in superconducting multilayers

    DEFF Research Database (Denmark)

    Pedersen, Niels Falsig; Madsen, Søren Peder

    2004-01-01

    We show how to construct fluxon modes from plasma modes in the inductively coupled stacked Josephson junctions, and consider some special cases of these fluxon modes analytically. In some cases we can find exact analytical solutions when we choose the bias current in a special way. We also consid...

  11. Local coding based matching kernel method for image classification.

    Directory of Open Access Journals (Sweden)

    Yan Song

    Full Text Available This paper mainly focuses on how to effectively and efficiently measure visual similarity for local feature based representation. Among existing methods, metrics based on Bag of Visual Word (BoV techniques are efficient and conceptually simple, at the expense of effectiveness. By contrast, kernel based metrics are more effective, but at the cost of greater computational complexity and increased storage requirements. We show that a unified visual matching framework can be developed to encompass both BoV and kernel based metrics, in which local kernel plays an important role between feature pairs or between features and their reconstruction. Generally, local kernels are defined using Euclidean distance or its derivatives, based either explicitly or implicitly on an assumption of Gaussian noise. However, local features such as SIFT and HoG often follow a heavy-tailed distribution which tends to undermine the motivation behind Euclidean metrics. Motivated by recent advances in feature coding techniques, a novel efficient local coding based matching kernel (LCMK method is proposed. This exploits the manifold structures in Hilbert space derived from local kernels. The proposed method combines advantages of both BoV and kernel based metrics, and achieves a linear computational complexity. This enables efficient and scalable visual matching to be performed on large scale image sets. To evaluate the effectiveness of the proposed LCMK method, we conduct extensive experiments with widely used benchmark datasets, including 15-Scenes, Caltech101/256, PASCAL VOC 2007 and 2011 datasets. Experimental results confirm the effectiveness of the relatively efficient LCMK method.

  12. Development of impedance matching technologies for ICRF antenna arrays

    Energy Technology Data Exchange (ETDEWEB)

    Pinsker, R.I.

    1998-03-01

    All high power ICRF heating systems include devices for matching the input impedance of the antenna array to the generator output impedance. For most types of antennas used, the input impedance is strongly time-dependent on timescales as rapid as 10-4 s, while the rf generators used are capable of producing full power only into a stationary load impedance. Hence, the dynamic response of the matching method is of great practical importance. In this paper, world-wide developments in this field over the past decade are reviewed. These techniques may be divided into several classes. The edge plasma parameters that determine the antenna array`s input impedance may be controlled to maintain a fixed load impedance. The frequency of the rf source can be feedback controlled to compensate for changes in the edge plasma conditions, or fast variable tuning elements in the transmission line between the generator output and the antenna input connections can provide the necessary time-varying impedance transformation. In lossy passive schemes, reflected power due to the time-varying impedance of the antenna array is diverted to a dummy load. Each of these techniques can be applied to a pre-existing antenna system. If a new antenna is to be designed, recent advances allow the antenna array to have the intrinsic property of presenting a constant load to the feeding transmission lines despite the varying load seen by each antenna in the array.

  13. Hybrid Video Coding Based on Bidimensional Matching Pursuit

    Directory of Open Access Journals (Sweden)

    Lorenzo Granai

    2004-12-01

    Full Text Available Hybrid video coding combines together two stages: first, motion estimation and compensation predict each frame from the neighboring frames, then the prediction error is coded, reducing the correlation in the spatial domain. In this work, we focus on the latter stage, presenting a scheme that profits from some of the features introduced by the standard H.264/AVC for motion estimation and replaces the transform in the spatial domain. The prediction error is so coded using the matching pursuit algorithm which decomposes the signal over an appositely designed bidimensional, anisotropic, redundant dictionary. Comparisons are made among the proposed technique, H.264, and a DCT-based coding scheme. Moreover, we introduce fast techniques for atom selection, which exploit the spatial localization of the atoms. An adaptive coding scheme aimed at optimizing the resource allocation is also presented, together with a rate-distortion study for the matching pursuit algorithm. Results show that the proposed scheme outperforms the standard DCT, especially at very low bit rates.

  14. Negative Capacitance Field Effect Transistors; Capacitance Matching and non-Hysteretic Operation

    OpenAIRE

    Saeidi, Ali; Jazaeri, Farzan; Bellando, Francesco; Stolichnov, Igor; Enz, Christian; Ionescu, Mihai Adrian

    2017-01-01

    This work experimentally demonstrates negative capacitance MOSFETs in hysteretic and non-hysteretic modes of operation. A PZT capacitor is externally connected to the gate of commercial nMOSFETs fabricated in 28nm CMOS technology to explore the negative capacitance effect. In hysteretic devices, subthreshold slope as steep as 10mV/dec is achieved in the region where the ferroelectric represents an S-shape polarization. In addition, a matching condition is achieved between a PZT capacitor and ...

  15. Effect of irradiation mode and filling technique on resin/dentin bonding strength in class I cavities Efeito do modo de ativação e da técnica restauradora na resistência de união entre compósito e dentina em cavidades classe I

    Directory of Open Access Journals (Sweden)

    Alex José Souza dos Santos

    2004-09-01

    Full Text Available Factors such as light-curing mode, filling technique and cavity configuration may affect the bonding strength to dentin. This study evaluated the effect of irradiation mode and filling technique on resin/dentin bonding strength on the buccal wall of class I cavities in human teeth. Occlusal enamel was removed to expose a flat dentin surface. Occlusal cavities (4 x 3 x 3 mm were prepared in dentin. The adhesive Single Bond was applied according to the manufacturer's instructions and TPH Spectrum composite resin was placed using the following: oblique incremental, horizontal incremental or bulk filling techniques. The composite resin was light-cured either by continuous (600 mW/cm² for 40 s or Soft-Start (250 mW/cm² for 10 s + 600 mW/cm² for 30 s modes. Specimens of the control group were obtained by bonding the material to the flat exposed buccal wall of the cavity (C-factor = 1. The teeth were stored in water at 37ºC for 24 h and prepared for microtensile testing. Bonded beams of approximately 0.8 mm² were obtained from the buccal wall and tested with a tension of 0.5 mm/min. Results were analyzed by two-way ANOVA, Tukey's test and Dunnett's test (alpha = 0.05. Incremental placement techniques with both irradiation modes produced higher bonding strength values than the bulk technique (p Fatores como o modo de ativação, a técnica restauradora e a configuração cavitária podem afetar a resistência adesiva à dentina. Este estudo avaliou os efeitos dos modos de ativação e das técnicas restauradoras na resistência de união compósito/dentina na parede vestibular de restaurações classe I. O esmalte oclusal dos dentes foi removido para expor uma superfície dentinária planificada. Cavidades oclusais (4 x 3 x 3 mm foram preparadas em dentina. O adesivo Single Bond foi aplicado de acordo com as instruções do fabricante, e o compósito TPH Spectrum, inserido através de três diferentes técnicas: oblíqua incremental, horizontal

  16. Modes of fossil preservation

    Science.gov (United States)

    Schopf, J.M.

    1975-01-01

    The processes of geologic preservation are important for understanding the organisms represented by fossils. Some fossil differences are due to basic differences in organization of animals and plants, but the interpretation of fossils has also tended to be influenced by modes of preservation. Four modes of preservation generally can be distinguished: (1) Cellular permineralization ("petrifaction") preserves anatomical detail, and, occasionally, even cytologic structures. (2) Coalified compression, best illustrated by structures from coal but characteristic of many plant fossils in shale, preserves anatomical details in distorted form and produces surface replicas (impressions) on enclosing matrix. (3) Authigenic preservation replicates surface form or outline (molds and casts) prior to distortion by compression and, depending on cementation and timing, may intergrade with fossils that have been subject to compression. (4) Duripartic (hard part) preservation is characteristic of fossil skeletal remains, predominantly animal. Molds, pseudomorphs, or casts may form as bulk replacements following dissolution of the original fossil material, usually by leaching. Classification of the kinds of preservation in fossils will aid in identifying the processes responsible for modifying the fossil remains of both animals and plants. ?? 1975.

  17. Spin and isospin modes

    International Nuclear Information System (INIS)

    Suzuki, T.; Sagawa, H.

    2000-01-01

    Complete text of publication follows. Spin and isospin modes in nuclei are investigated. We discuss some of the following topics. 1. Spin-dipole excitations in 12 C and 16 O are studied (1). Effects of tensor and spin-orbit interactions on the distribution of the strengths are investigated, and neutral current neutrino scattering cross sections in 16 O are obtained for heavy-flavor neutrinos from the supernovae. 2. Gamow-Teller (GT) and spin-dipole (SD) modes in 208 Bi are investigated. Quenching and fragmentation of the GT strength are discussed (2). SD excitations and electric dipole (E1) transitions between the GT and SD states are studied (3). Calculated E1 strengths are compared with the sum rule values obtained within the 1p-1h and 1p-1h + 2p-2h configuration spaces. 3. Coulomb displacement energy (CDE) of the IAS of 14 Be is calculated, and the effects of the halo on the CDE and the configuration of the halo state are investigated. 4. Spreading width of IAS and isospin dependence of the width are investigated (4). Our formula for the width explains very well the observed isospin dependence (5). (author)

  18. Successive odor matching- and non-matching-to-sample in rats: A reversal design.

    Science.gov (United States)

    Bruce, Katherine; Dyer, Katherine; Mathews, Michael; Nealley, Catharine; Phasukkan, Tiffany; Prichard, Ashley; Galizio, Mark

    2017-07-13

    There is a growing body of research on matching- and non-matching-to-sample (MTS, NMTS) relations with rats using olfactory stimuli; however, the specific characteristics of this relational control are unclear. In the current study we examine MTS and NMTS in rats with an automated olfactometer using a successive (go, no-go) procedure. Ten rats were trained to either match- or non-match-to-sample with common scents (apple, cinnamon, etc.) as olfactory stimuli. After matching or non-matching training with four odorants, rats were tested for transfer twice with four new odorants on each test. Most rats trained on MTS showed immediate transfer to new stimuli, and most rats trained on NMTS showed full transfer by the second set of new odors. After meeting criterion on the second transfer test, the contingencies were reversed with four new odor stimuli such that subjects trained on matching were shifted to non-matching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new odorants. These data extend previous studies on same-different concept formation in rats, showing strong generalization requiring few exemplars. The critical role of olfactory stimuli is discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Do people match surface reflectance fundamentally differently than they match emitted light?

    NARCIS (Netherlands)

    Granzier, J.J.M.; Brenner, E.; Smeets, J.B.J.

    2009-01-01

    We compared matches between colours that were both presented on a computer monitor or both as pieces of paper, with matching the colour of a piece of paper with a colour presented on a computer monitor and vice versa. Performance was specifically poor when setting an image on a computer monitor to

  20. Recent trends in applicants and the matching process for the integrated plastic surgery match.

    Science.gov (United States)

    Super, Nikki; Tieman, Joshua; Boucher, Kenneth; Rockwell, William Bradford; Agarwal, Jayant P

    2013-10-01

    Matching into a plastic surgery (PS) residency program is a highly competitive process. Selection criteria are very stringent and may influence an applicant's candidacy and application strategy. The purpose of this study was to evaluate recent trends of applicants matching into integrated PS programs using published National Resident Match Program data. Residency match data were gathered for application years 2002 to 2011 using the National Resident Match Program/Association of American Medical Colleges databases. Analyses were limited to the US senior group and excluded the non-US senior group because of the small numbers in the latter group. For all data sets, a logistic regression was performed to analyze the statistical significance of the data. The overall match rate continues to approximately 50%. United States senior applicants were more likely to rank PS only versus PS and others (PS + other) over time (P ranking PS only were more likely to match versus US senior applicants ranking PS + other (odds ratio, 1.71; P rank PS only. The proportion of applicants ranking PS only is steadily rising. The ranking strategy used by US senior applicants is self-selecting into a more competitive (PS only) and less competitive (PS + other) applicant pool. If this continues, nearly 50% of applicants will not match and could be left scrambling for an alternative residency position. These findings therefore suggest that all candidates, regardless of their perceived application strength, should consider having a "backup plan."