3,141 research outputs found

    Prospects for direct detection of circular polarization of gravitational-wave background

    Get PDF
    We discussed prospects for directly detecting circular polarization signal of gravitational wave background. We found it is generally difficult to probe the monopole mode of the signal due to broad directivity of gravitational wave detectors. But the dipole (l=1) and octupole (l=3) modes of the signal can be measured in a simple manner by combining outputs of two unaligned detectors, and we can dig them deeply under confusion and detector noises. Around f~0.1mHz LISA will provide ideal data streams to detect these anisotropic components whose magnitudes are as small as ~1 percent of the detector noise level in terms of the non-dimensional energy density \Omega_{GW}(f).Comment: 5 pages, 1 figure, PRL in pres

    Evaluasi Pemilihan Supplier Terbaik Menggunakan Metode Taguchi Loss Functions Dan Analytical Hierarchy Process Di PT Indomaju Textindo Kudus

    Full text link
    PT Indomaju Textindo merupakan produsen karung plastik yang menggunakan kalsium sebagai salah satu bahan bakunya. Saat ini terdapat 4 supplier kalsium, sementara masing – masing supplier memiliki performansi yang berbeda. Untuk itu Perusahaan menginginkan evaluasi terhadap masing – masing supplier. Penelitian ini bertujuan mengidentifikasi kriteria - kriteria yang menjadi pertimbangan di dalam pemilihan supplier dan melakukan pembobotan terhadap kriteria-kriteria tersebut, menentukan nilai loss function masing – masing supplier dan yang terakhir menentukan supplier kalsium terbaik. Metode yang digunakan untuk mengevaluasi supplier adalah Taguchi Loss Function dan Analytical Hierarchy Process (AHP). Taguchi Loss Function digunakan untuk menghitung loss function masing-masing supplier, sedangkan AHP digunakan untuk membobotkan masing-masing kriteria. Kriteria pemilihan supplier dari penelitian ini adalah harga, kualitas, proses pengiriman dan pengepakan dengan bobot untuk masing-masing kriteria secara berturut-turut adalah 29%, 54%, 11% dan 6%. Besarnya loss function yang dibebankan pada Perusahaan akibat ketidaksesuaian terendah adalah dari supplier Indomaju, sehingga supplier ini yang, sehingga supplier yang memberikan kerugian minimum bagi Perusahaan yaitu supplier Indomaju. Kata kunci : kalsium, supplier, Taguchi Loss Function, Analytical Hierarchy Process PT Indomaju Textindo is a woven bag producer which used calcium as one of raw material in the production. In this time there are 4 calcium, whereas each of supplier have different performance, so the company want to evaluate their suppliers. Objective of this research are indentifing of criterions in supplier selection process and wight of the criterions, determining loss function value of the each suppliers and chosening the best supplier. This research used Taguchi Loss Function dan Analytical Hierarchy Process (AHP) for determining the best supplier. Taguchi Loss Function for calculating loss function each of supplier, while AHP for wighting aech of criterion. Criterion of the supplier selection are price, quality, delivery process and packaging, with wight for each criterion are 29%, 54%, 11% and 6% successively. The lowest value of Loss function is owned by Indomaju supplier's, so its given minimum loss for the company

    A randomized, placebo-controlled trial of the benzoquinone idebenone in a mouse model of OPA1-related dominant optic atrophy reveals a limited therapeutic effect on retinal ganglion cell dendropathy and visual function

    Get PDF
    Dominant optic atrophy (DOA) arises from mutations in the OPA1 gene that promotes fusion of the inner mitochondrial membrane and plays a role in maintaining ATP levels. Patients display optic disc pallor, retinal ganglion cell (RGC) loss and bilaterally reduced vision. We report a randomized, placebo-controlled trial of idebenone at 2000 mg/kg/day in 56 Opa1 mutant mice (B6;C3-Opa1Q285STOP), with RGC dendropathy and visual loss, and 63 wildtype mice. We assessed cellular responses in the retina, brain and liver and RGC morphology, by diolistic labeling, Sholl analysis and quantification of dendritic morphometric features. Vision was assessed by optokinetic responses. ATP levels were raised by 0.57 nmol/mg (97.73%, p = 0.035) in brain from idebenone-treated Opa1 mutant mice, but in the liver there was an 80.35% (p = 0.011) increase in oxidative damage. NQO1 expression in Opa1 mutant mice was reduced in the brain (to 30.5%, p = 0.002) but not in retina, and neither expression level was induced by idebenone. ON-center RGCs failed to show major recovery, other than improvements in secondary dendritic length (by 53.89%, p = 0.052) and dendritic territory (by 2.22 × 104 μm2 or 90.24%, p = 0.074). An improvement in optokinetic response was observed (by 12.2 ± 3.2 s, p = 0.003), but this effect was not sustained over time. OFF-center RGCs from idebenone-treated wildtype mice showed shrinkage in total dendritic length by 2.40 mm (48.05%, p = 0.025) and a 47.37% diminished Sholl profile (p = 0.029). Visual function in wildtype idebenone-treated mice was impaired (2.9 fewer head turns than placebo, p = 0.007). Idebenone appears largely ineffective in protecting Opa1 heterozygous RGCs from dendropathy. The detrimental effect of idebenone in wildtype mice has not been previously observed and raises some concerns

    Energy Efficient Engine combustor test hardware detailed design report

    Get PDF
    The Energy Efficient Engine (E3) Combustor Development effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent was to evolve a design which meets the stringent emissions and life goals of the E3 as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this development effort will be incorporated into the engine combustion system hardware design. This advanced engine combustion system will then be evaluated in component testing to verify the design intent. What is evolving from this development effort is an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3. Fuel nozzle, diffuser, starting, and emissions design studies are discussed

    Energy Efficient Engine (E3) combustion system component technology performance report

    Get PDF
    The Energy Efficient Engine (E3) combustor effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent of this effort was to evolve a design that meets the stringent emissions and life goals of the E3, as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this effort was incorporated into the engine combustion hardware design. The advanced engine combustion system was then evaluated in component testing to verify the design intent. What evolved from this effort was an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3

    Nonlinear Velocity-Density Coupling: Analysis by Second-Order Perturbation Theory

    Get PDF
    Cosmological linear perturbation theory predicts that the peculiar velocity V(x)V(x) and the matter overdensity δ(x)\delta(x) at a same point xx are statistically independent quantities, as log as the initial density fluctuations are random Gaussian distributed. However nonlinear gravitational effects might change the situation. Using framework of second-order perturbation theory and the Edgeworth expansion method, we study local density dependence of bulk velocity dispersion that is coarse-grained at a weakly nonlinear scale. For a typical CDM model, the first nonlinear correction of this constrained bulk velocity dispersion amounts to 0.3δ\sim 0.3\delta (Gaussian smoothing) at a weakly nonlinear scale with a very weak dependence on cosmological parameters. We also compare our analytical prediction with published numerical results given at nonlinear regimes.Comment: 16 pages including 2 figures, ApJ 537 in press (July 1

    D-term Inflation and Nonperturbative Kahler Potential of Dilaton

    Full text link
    We study the DD-term inflation scenario with a nonperturbative K\"ahler potential of the dilaton field. Although the FI term which leads an inflationary expansion is given by the derivative of the K\"ahler potential with respect to the dilaton in heterotic string models with anomalous U(1), the too large magnitude is problematic for a viable DD-term inflation. In this paper, we point out that the K\"ahler potential with a nonperturbative term can reduce the magnitude of FI term to desired values while both the dilaton stabilization and DD-term domination in the potential are realized by nonperturbative superpotential.Comment: 13 pages, latex, 3 figure

    Twin wall of cubic-tetragonal ferroelastics

    Full text link
    We derive solutions for the twin wall linking two tetragonal variants of the cubic-tetragonal ferroelastic transformation, including for the first time the dilatational and shear energies and strains. Our solutions satisfy the compatibility relations exactly and are obtained at all temperatures. They require four non-vanishing strains except at the Barsch-Krumhansl temperature TBK (where only the two deviatoric strains are needed). Between the critical temperature and TBK, material in the wall region is dilated, while below TBK it is compressed. In agreement with experiment and more general theory, the twin wall lies in a cubic 110-type plane. We obtain the wall energy numerically as a function of temperature and we derive a simple estimate which agrees well with these values.Comment: 4 pages (revtex), 3 figure

    Cosmological test of gravity with polarizations of stochastic gravitational waves around 0.1-1 Hz

    Full text link
    In general relativity, a gravitational wave has two polarization modes (tensor mode), but it could have additional polarizations (scalar and vector modes) in the early stage of the universe, where the general relativity may not strictly hold and/or the effect of higher-dimensional gravity may become significant. In this paper, we discuss how to detect extra-polarization modes of stochastic gravitational wave background (GWB), and study the separability of each polarization using future space-based detectors such as BBO and DECIGO. We specifically consider two plausible setups of the spacecraft constellations consisting of two and four clusters, and estimate the sensitivity to each polarization mode of GWBs. We find that a separate detection of each polarization mode is rather sensitive to the geometric configuration and distance between clusters and that the clusters should be, in general, separated by an appropriate distance. This seriously degrades the signal sensitivity, however, for suitable conditions, space-based detector can separately detect scalar, vector and tensor modes of GWBs with energy density as low as ~10^-15.Comment: 16 pages, 11 figure

    Geometrical Aspects on Parameter estimation of stochastic gravitational wave background: beyond the Fisher analysis

    Full text link
    The maximum likelihood method is often used for parameter estimation in gravitational wave astronomy. Recently, an interesting approach was proposed by Vallisneri to evaluate the distributions of parameter estimation errors expected for the method. This approach is to statistically analyze the local peaks of the likelihood surface, and works efficiently even for signals with low signal-to-noise ratios. Focusing special attention to geometric structure of the likelihood surface, we follow the proposed approach and derive formulae for a simplified model of data analysis where the target signal has only one intrinsic parameter, along with its overall amplitude. Then we apply our formulae to correlation analysis of stochastic gravitational wave background with a power-law spectrum. We report qualitative trends of the formulae using numerical results specifically obtained for correlation analysis with two Advanced-LIGO detectors.Comment: 23 pages, to be published in PR
    corecore