620 research outputs found

    Computationally Efficient Implementation of Convolution-based Locally Adaptive Binarization Techniques

    Full text link
    One of the most important steps of document image processing is binarization. The computational requirements of locally adaptive binarization techniques make them unsuitable for devices with limited computing facilities. In this paper, we have presented a computationally efficient implementation of convolution based locally adaptive binarization techniques keeping the performance comparable to the original implementation. The computational complexity has been reduced from O(W2N2) to O(WN2) where WxW is the window size and NxN is the image size. Experiments over benchmark datasets show that the computation time has been reduced by 5 to 15 times depending on the window size while memory consumption remains the same with respect to the state-of-the-art algorithmic implementation

    A New Approach to Assess the Gastrocnemius Muscle Volume in Rodents Using Ultrasound; Comparison with the Gastrocnemius Muscle Index

    Get PDF
    Introduction: The purpose of this study was to determine the reliability and validity of a new non-invasive ultrasound technique to measure gastrocnemius muscle atrophy after nerve denervation in an animal model. Methods: In sixteen rodents an eight mm sciatic nerve gap was created. In the following 8 weeks, each week, two rodents were euthanized and the gastrocnemius muscle was examined using two different ultrasound systems and two investigators. The standardized ultrasound measurement protocol consisted of identifying pre-defined anatomical landmarks: 1) the fibula, 2) the fibular nerve, and 3) the junction between the most distal point of the semitendinosus muscle and gastrocnemius muscle. Consequently, we measured the muscle thickness as the length of the line between the fibula and the junction between the two muscles, perpendicular to the fibular nerve. After the ultrasound recording, the muscle mass was determined. Results: A steep decline of muscle weight of 24% was observed after one week. In the following weeks, the weight further decreased and then remained stable from 6 weeks onwards, resulting in a maximal muscle weight decrease of 82%. The correlation coefficient was >0.96 between muscle diameter and weight using both ultrasound systems. The inter-rater reliability was excellent for both devices on the operated side (ICC of 0.99 for both ultrasound systems) and good for the non-operated site (ICC's: 0.84 & 0.89). The difference between the muscle mass ratio and the muscle thickness ratio was not more than 5% with two outliers of approximately 13%. Discussion: We have developed an innovative, highly reliable technique for quantifying muscle atrophy after nerve injury. This technique allows serial measurements in the same animal over time. This is a significant advantage compared to the conventional technique for quantifying muscle atrophy, which requires sacrificing the animal

    Deformation of Super Yang-Mills Theories in R-R 3-form Background

    Full text link
    We study deformation of N=2 and N=4 super Yang-Mills theories, which are obtained as the low-energy effective theories on the (fractional) D3-branes in the presence of constant Ramond-Ramond 3-form background. We calculate the Lagrangian at the second order in the deformation parameter from open string disk amplitudes. In N=4 case we find that all supersymmetries are broken for generic deformation parameter but part of supersymmetries are unbroken for special case. We also find that classical vacua admit fuzzy sphere configuration. In N=2 case we determine the deformed supersymmetries. We rewrite the deformed Lagrangians in terms of N=1 superspace, where the deformation is interpreted as that of coupling constants.Comment: v2: reference added, v3: published version in JHE

    Measurement of K^+ \to \pi^0 \mu^+ \nu \gamma decay using stopped kaons

    Full text link
    The K^+ \to \pi^0 \mu^+ \nu \gamma (Kμ3γK_{\mu 3 \gamma}) decay has been measured with stopped positive kaons at the KEK 12 GeV proton synchrotron. A Kμ3γK_{\mu 3 \gamma} sample containing 125 events was obtained. The partial branching ratio Br(Kμ3γ,Eγ>30MeV,θμ+γ>20∘)Br(K_{\mu 3 \gamma}, E_{\gamma}>30 {\rm MeV}, \theta_{\mu^+ \gamma}>20^{\circ}) was found to be [2.4±0.5(stat)±0.6(syst)]×10−5[2.4 \pm 0.5(stat) \pm 0.6(syst)]\times 10^{-5}, which is in good agreement with theoretical predictions.Comment: 12 pages, 3 figures, to be published in Physics Letters

    Instanton Calculus in R-R 3-form Background and Deformed N=2 Super Yang-Mills Theory

    Full text link
    We study the ADHM construction of instantons in N=2 supersymmetric Yang-Mills theory deformed in constant Ramond-Ramond (R-R) 3-form field strength background in type IIB superstrings. We compare the deformed instanton effective action with the effective action of fractional D3/D(-1) branes at the orbifold singularity of C^2/Z_2 in the same R-R background. We find discrepancy between them at the second order in deformation parameters, which comes from the coupling of the translational zero modes of the D(-1)-branes to the R-R background. We improve the deformed action by adding a term with space-time dependent gauge coupling. Although the space-time action differs from the action in the omega-background, both actions lead to the same instanton equations of motion at the lowest order in gauge coupling.Comment: 27 pages, version to appear in JHE

    Measurement of direct photon emission in K+→π+π0γK^+ \to \pi^+ \pi^0 \gamma decay using stopped positive kaons

    Full text link
    The radiative decay K+→π+π0γK^+ \to \pi^+ \pi^0 \gamma (Kπ2γK_{\pi 2 \gamma}) has been measured with stopped positive kaons. A Kπ2γK_{\pi 2 \gamma} sample containing 4k events was analyzed, and the Kπ2γK_{\pi 2 \gamma} branching ratio of the direct photon emission process was determined to be [6.1±2.5(stat)±1.9(syst)]×10−6[6.1\pm2.5({\rm stat})\pm1.9({\rm syst})]\times 10^{-6}. No interference pattern with internal bremsstrahlung was observed.Comment: 12 pages, 6 figures, 2 tables, to be published in Phys. Lett.

    Measurement of the Dalitz plot slope parameters for K- -> pi0 pi0 pi- decay using ISTRA+ detector

    Get PDF
    The Dalitz plot slope parameters g, h and k for the K- -> pi0 pi0 pi- decay have been measured using in-flight decays detected with the ISTRA+ setup operating in the 25 GeV negative secondary beam of the U-70 PS. About 252 K events with four-momenta measured for the pi- and four involved photons were used for the analysis. The values obtained g=0.627+/-0.004(stat)+/-0.010(syst), h=0.046+/-0.004(stat)+/-0.012(syst), k=0.001+/-0.001(stat)+/-0.002(syst) are consistent with the world averages dominated by K+ data, but have significantly smaller errors.Comment: LaTeX, 10 pages, 8 eps-figures, update of IHEP 2002-1

    p-wave phase shift and scattering length of 6^6Li

    Full text link
    We have calculated the p-wave phase shifts and scattering length of 6^6Li. For this we solve the pp partial wave Schr\"odinger equation and analyze the validity of adopting the semiclassical solution to evaluate the constant factors in the solution. Unlike in the ss wave case, the semiclassical solution does not provide unique value of the constants. We suggest an approximate analytic solution, which provides reliable results in special cases. Further more, we also use the variable phase method to evaluate the phase shifts. The p-wave scattering lengths of 132^{132}Cs and 134^{134}Cs are calculated to validate the schemes followed. Based on our calculations, the value of the pp wave scattering length of 6^6Li is −45ao-45a_o.Comment: 10 figure

    Measurement of Γ(Kμ3)/Γ(Ke3)\Gamma(K_{\mu 3})/\Gamma(K_{e3}) ratio using stopped positive kaons

    Full text link
    The ratio of the K+→π0μ+νK^{+}\to \pi^{0} \mu^{+} \nu (Kμ3+K_{\mu3}^+) and K+→π0e+νK^{+}\to \pi^{0} e^{+} \nu (Ke3+K_{e3}^+) decay widths, Γ(Kμ3)/Γ(Ke3)\Gamma(K_{\mu 3})/\Gamma(K_{e3}), has been measured with stopped positive kaons. Kμ3+K_{\mu3}^+ and Ke3+K_{e3}^+ samples containing 2.4×104\times 10^4 and 4.0×104\times 10^4 events, respectively, were analyzed. The Γ(Kμ3)/Γ(Ke3)\Gamma(K_{\mu3})/\Gamma(K_{e3}) ratio was obtained to be 0.671±\pm0.007(stat.)±\pm0.008(syst.) calculating the detector acceptance by a Monte Carlo simulation with the assumption of μ\mu-ee universality in Kl3+K_{l3}^+ decay. The coefficient of the q2q^2 dependent term of the f0f_0 form factor was also determined to be λ0\lambda_0=0.022±\pm0.005(stat.)±\pm0.004(syst.).Comment: 12 pages, 6 figure
    • …
    corecore