High Precision In Order Research Articles

Scalar fields and parametrized spherically symmetric black holes: Can one hear the shape of space-time?

In this work we study whether parametrized spherically symmetric black hole solutions in metric theories of gravity can appear to be isospectral when studying perturbations. From a theory agnostic point of view, the test scalar field wave equation is the ideal starting point to approach the quasinormal mode spectrum in alternative black hole solutions. We use a parametrization for the metric proposed by Rezzolla and Zhidenko, as well as the higher order WKB method in the determination of the quasinormal mode spectra. We look for possible degeneracies in a tractable subset of the parameter space with respect to the Schwarzschild quasinormal modes. Considering the frequencies and damping times of the expected observationally most relevant quasinormal modes, we find such degeneracies. We explicitly demonstrate that the leading Schwarzschild quasinormal modes can be approximated by alternative black hole solutions when their mass is treated as free parameter. In practice, we conclude that the mass has to be known with extremely high precision in order to restrict the leading terms in the metric expansion to currently known limits coming from the PPN expansion. Possible limitations of using the quasinormal mode ringdown to investigate black hole space-times are discussed.

Increased phosphorus use efficiency in basil grown hydroponically with low phosphorus concentration and saline water

Phosphorus is one of the most important nutrients in agriculture for its physiological, ecological and economic implications. Phosphorus reserves are decreasing around the globe and therefore its price has been increasing in the last years. Phosphorus is subjected to many chemical phenomena in the root zone that make its management in cropping systems more and more difficult. In soilless culture, P can be monitored and managed with high precision in order to improve its uptake by roots and minimize its losses. In this experiment, basil (Ocimum basilicum L.) was grown hydroponically with different P (H(2)PO(4-)) and NaCl concentrations in the nutrient solution: i) to evaluate the effects of P and salinity on plant yield and mineral nutrition, and ii) to verify the possibility to decrease P concentration without growth reduction. Three P concentrations (i.e., 0.25, 0.5, and 1.0 mol m(‑3)) were combined with increasing NaCl concentrations (i.e., 5, 15, and 30 mol m(‑3)) in the root zone. Plants faced the low concentration of P in the nutrient solution by increasing the root/shoot ratio. Plant yield was not influenced by P and NaCl levels. The agronomic use efficiency of P was significantly increased by the low P supply. These findings suggest that basil can be grown hydroponically at P concentration much lower than those currently used in commercial operations.

Nonparametric Inference for VaR, CTE, and Expectile with High-Order Precision

Value-at-Risk and Conditional Tail Expectation are the two most frequently applied risk measures in quantitative risk management. Recently expectile has also attracted much attention as a risk measure because of its elicitability property. This article establishes empirical likelihood–based estimation with high-order precision for these three risk measures. The superiority of the estimation is justified both in theory and via simulation studies. Extensive simulation studies confirm that our method significantly improves the coverage probabilities for interval estimation of the three risk measures, compared to three competing methods available in the literature.

Nonparametric Inference for VaR, CTE, and Expectile with High-order Precision

Value-at-Risk (VaR) and Conditional Tail Expectation (CTE) are the two most frequently applied risk measures in quantitative risk management. Recently, expectile has also attracted much attention as a risk measure due to its elicitability property. This paper establishes empirical likelihood based estimation with high-order precision for these three risk measures. The superiority of the estimation is justified both in theory and via simulation studies. Extensive simulation studies confirm that our method signifificantly improves the coverage probabilities for interval estimation of the three risk measures, compared to three competing methods available in the literature.

Squeezing-enhanced rotating-angle measurement beyond the quantum limit

Aided by quantum sources, quantum metrology helps to enhance measurement precision. Here, we introduce a method to enhance the measurement of a rotation angle. As a proof of principle, assisted by a quantum state called the squeezed orbital-angular-position (OAP) state and balance homodyne detection, we demonstrate in experiments 3 dB-enhanced measurements of a rotation-angle beyond the shot noise limit. A precision of up to 17.7 nrad/Hz is obtained. Furthermore, we discuss means to further improve the measurement with a high-order precision OAP squeezed state. The method holds promise for future practical applications, such as in high-sensitive Sagnac interferometry.

3-D In Vitro Acoustic Super-Resolution and Super-Resolved Velocity Mapping Using Microbubbles.

Standard clinical ultrasound (US) imaging frequencies are unable to resolve microvascular structures due to the fundamental diffraction limit of US waves. Recent demonstrations of 2-D super-resolution both in vitro and in vivo have demonstrated that fine vascular structures can be visualized using acoustic single bubble localization. Visualization of more complex and disordered 3-D vasculature, such as that of a tumor, requires an acquisition strategy which can additionally localize bubbles in the elevational plane with high precision in order to generate super-resolution in all three dimensions. Furthermore, a particular challenge lies in the need to provide this level of visualization with minimal acquisition time. In this paper, we develop a fast, coherent US imaging tool for microbubble localization in 3-D using a pair of US transducers positioned at 90°. This allowed detection of point scatterer signals in 3-D with average precisions equal to [Formula: see text] in axial and elevational planes, and [Formula: see text] in the lateral plane, compared to the diffraction limited point spread function full-widths at half-maximum of 488, 1188, and [Formula: see text] of the original imaging system with a single transducer. Visualization and velocity mapping of 3-D in vitro structures was demonstrated far beyond the diffraction limit. The capability to measure the complete flow pattern of blood vessels associated with disease at depth would ultimately enable analysis of in vivo microvascular morphology, blood flow dynamics, and occlusions resulting from disease states.

An analytical singular element for interface V-shaped notches in Bi-material Kirchhoff plate bending

An analytical singular element with arbitrary high-order precision is constructed basing on the analytical symplectic eigenfunction of a bi-material V-shaped notch in Kirchhoff plate bending. Stress intensity coefficients for a bi-material notch can be determined directly from the expansion coefficients of the eigensolution. The high accuracy of this singular element is demonstrated by numerical examples. The present method is an effective approach for analysis of bi-material V-shaped notches in a Kirchhoff plate.

Bartlett-corrected two-sample adjusted empirical likelihood via resampling

ABSTRACTTo construct confidence regions for the difference of two population means, Liu and Yu (2010) proposed a two-sample adjusted empirical likelihood (AEL) with high-order precision. However, two issues have not been well addressed. The first one is that the AEL ratio function is bounded such that the size of the confidence regions may overly expand when the sample sizes are small and/or the dimension of data is large. The second issue is that its high-order precision relies on accurate estimation of the Bartlett factor, while accurately estimating the Bartlett factor is a serious challenge. In order to address these two problems simultaneously, we propose a two-sample modified AEL to ensure the boundedness of confidence regions and preserve the Bartlett correctability. A two-stage procedure is proposed for constructing accurate confidence regions via resampling. The finite-sample performance of the proposed method is illustrated by simulations and a real-data example.

Determination and evaluation of the thermophysical properties of an alkali carbonate eutectic molten salt.

The thermal physical properties of Li2CO3-Na2CO3-K2CO3 eutectic molten salt were comprehensively investigated. It was found that the liquid salt can remain stable up to 658 °C (the onset temperature of decomposition) by thermal analysis, and so the investigations on its thermal physical parameters were undertaken from room temperature to 658 °C. The density was determined using a self-developed device, with an uncertainty of ±0.00712 g cm(-3). A cooling curve was obtained from the instrument, giving the liquidus temperature. For the first time, we report the obtainment of the thermal diffusivity using a laser flash method based on a special crucible design and establishment of a specific sample preparation method. Furthermore, the specific heat capacity was also obtained by use of DSC, and combined with thermal diffusivity and density, was used to calculate the thermal conductivity. We additionally built a rotating viscometer with high precision in order to determine the molten salt viscosity. All of these parameters play an important part in the energy storage and transfer calculation and safety evaluation for a system.

ANALISA DAN PERANCANGAN APLIKASI SISTEM INFORMASI PENGGAJIAN KARYAWAN PADA PT. ADITYA BUANA INTER SUNGAILIAT BANGKA

ABSTRAK Adapun tujuan dari penelitian ini adalah menghasilkan sistem informasi penggajian karyawan secara komputerisasi dimana sistem informasi penggajian karyawan PT. Aditya Buana Inter yang sebelumnya masih menggunakan sistem manual. Hasil yang ingin dicapai dari penelitian ini adalah dengan adanya aplikasi sistem informasi penggajian karyawan yang sudah terkomputerisasi ini dapat memberikan kemudahan dalam pelayanan dan penyajian informasi, meningkatkan kinerja serta pengolahan data menjadi lebih baik, tepat, cepat dan akurat serta mempercepat dalam pembuatan laporan gaji karyawan. Peningkatan kinerja kerja tidak terlepas dari sarana dan prasarana, salah satunya adalah dukungan teknologi dan sistem informasi yang sesuai dengan kebutuhan. Dimana data dapat diproses dan diolah sehingga menghasilkan suatu informasi guna mendukung keputusan yang baik. Pada masa sekarang, suatu perusahaan sebaiknya dapat bekerja dengan cepat, tepat, dan benar dengan tingkat ketelitian yang tinggi agar dapat terus berjalan dan bertahan dalam persaingan yang kompetitif. Sistem informasi yang dibutuhkan juga harus akurat, tepat waktu, dan fleksibel guna menunjang kelancaran kegiatan sehari-hari perusahaan. Sistem Informasi Penggajian Karyawan pada PT. Aditya Buana Inter Sungailiat Kabupaten Bangka ini merupakan sistem informasi penggajian karyawan yang dirancang dengan menggunakan metodologi berorientasi objek dengan alat bantu UML (Unified Modelling Language), pengamatan langsung dan wawancara dengan pihak yang terkait. Kata kunci: penggajian, teknologi, aplikasi, sistem informasi, UML, metodologi berorientasi objek.

Non-Gaussianities in the topological charge distribution of the SU(3) Yang-Mills theory

We study the topological charge distribution of the SU(3) Yang--Mills theory with high precision in order to be able to detect deviations from Gaussianity. The computation is carried out on the lattice with high statistics Monte Carlo simulations by implementing a naive discretization of the topological charge evolved with the Yang--Mills gradient flow. This definition is far less demanding than the one suggested from Neuberger's fermions and, as shown in this paper, in the continuum limit its cumulants coincide with those of the universal definition appearing in the chiral Ward identities. Thanks to the range of lattice volumes and spacings considered, we can extrapolate the results for the second and fourth cumulant of the topological charge distribution to the continuum limit with confidence by keeping finite volume effects negligible with respect to the statistical errors. Our best results for the topological susceptibility is t_0^2*chi=6.67(7)*10^-4, where t_0 is a standard reference scale, while for the ratio of the forth cumulant over the second we obtain R=0.233(45). The latter is compatible with the expectations from the large Nc expansion, while it rules out the theta-behavior of the vacuum energy predicted by the dilute instanton model. Its large distance from 1 implies that, in the ensemble of gauge configurations that dominate the path integral, the fluctuations of the topological charge are of quantum non-perturbative nature.

Optical study of solar tower power plants

The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature.

Upgraded Trigger Readout Electronics for the ATLAS LAr Calorimeters for Future LHC Running

The ATLAS Liquid Argon (LAr) calorimeters produce almost 200K signals that are digitized and processed by the front-end and back-end electronics for every triggered event. Additionally, the front-end electronics sums analog signals to provide coarse-grained energy sums to the first- level (L1) trigger system. The current design was optimized for the nominal LHC luminosity of 1034cm−2s−1. In order to retain the capability to trigger on low energy electrons and photons when the LHC is upgraded to higher luminosity, an improved LAr calorimeter trigger readout is proposed and being constructed. The new trigger readout system makes available the fine segmentation of the calorimeter at the L1 trigger with high precision in order to reduce the QCD jet background in electron, photon and tau triggers, and to improve jet and missing ET trigger performance. The new LAr Trigger Digitizer Board is designed to receive the higher granularity signals, digitize them on-detector and send them via fast optical links to a new Digital Processing System. The reconstructed energies of trigger readout channels after digital filtering are transmitted to the L1 system, allowing the extraction of improved trigger signatures. This contribution presents the motivation for the upgrade, the concept for the new trigger readout and the expected performance of the new trigger, and describes the components being developed for the new system.

Level-specific correction for nonparametric likelihoods

The popular empirical likelihood method not only has a convenient chi-square limiting distribution but is also Bartlett correctable, leading to a high-order coverage precision of the resulting confidence regions. Meanwhile, it is one of many nonparametric likelihoods in the Cressie–Read power divergence family. The other likelihoods share many attractive properties but are not Bartlett correctable. In this paper, we develop a new technique to achieve the effect of being Bartlett correctable. Our technique is generally applicable to pivotal quantities with chi-square limiting distributions. Numerical experiments and an example reveal that the method is successful for several important nonparametric likelihoods.

IMPROVING THE PRECISION OF ASTROMETRY FOR SPACE DEBRIS

The data reduction method for optical space debris observations has many similarities with the one adopted for surveying near-Earth objects; however, due to several specific issues, the image degradation is particularly critical, which makes it difficult to obtain precise astrometry. An automatic image reconstruction method was developed to improve the astrometry precision for space debris, based on the mathematical morphology operator. Variable structural elements along multiple directions are adopted for image transformation, and then all the resultant images are stacked to obtain a final result. To investigate its efficiency, trial observations are made with Global Positioning System satellites and the astrometry accuracy improvement is obtained by comparison with the reference positions. The results of our experiments indicate that the influence of degradation in astrometric CCD images is reduced, and the position accuracy of both objects and stellar stars is improved distinctly. Our technique will contribute significantly to optical data reduction and high-order precision astrometry for space debris.

An Innovative Image Reconstruction Method for High-Precision Astrometry

An automatic image-reconstruction method is presented, based on the use of a mathematical morphology operator. Variable structural elements along multiple directions are adopted for image convolution, and then all of the corresponding convolved images are stacked to obtain a final result. To investigate its efficiency, both simulated images and raw CCD images, produced by a trial observation using a 45-cm telescope, are tested. With this method, the influence of degradation in astrometric CCD images is reduced, and the position accuracy of background stars is distinctly improved. This method will contribute significantly to optical data reduction and high-order precision astrometry.

Measurement of High-Pressure Shock Waves in Cryogenic Deuterium-Tritium Ice Layered Capsule Implosions on NIF

The first measurements of multiple, high-pressure shock waves in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility have been performed. The strength and relative timing of these shocks must be adjusted to very high precision in order to keep the DT fuel entropy low and compressibility high. All previous measurements of shock timing in inertial confinement fusion implosions [T. R. Boehly etal., Phys. Rev. Lett. 106, 195005 (2011), H. F. Robey etal., Phys. Rev. Lett. 108, 215004 (2012)] have been performed in surrogate targets, where the solid DT ice shell and central DT gas regions were replaced with a continuous liquid deuterium (D2) fill. This report presents the first experimental validation of the assumptions underlying this surrogate technique.

Newton–Kantorovich/Pseudospectral Solution to Perturbed Astrodynamic Two-Point Boundary-Value Problems

The Newton–Kantorovich/Chebyshev pseudospectral method is systematically investigated to solve perturbed astrodynamic two-point boundary-value problems. Because many unperturbed astrodynamic problems have been solved and the perturbations are relatively small, the unperturbed solutions can serve as good initial approximations. The differential equations describing the perturbed problem are linearized about the nominal (approximate) solution, and the pseudospectral method is used to solve the linearized differential equations. By successively updating the nominal solution with the Newton–Kantorovich approach, the linearized solving procedure is iterated to achieve high-order precision. Because no numerical integration is needed and only linear algebraic equations are solved, the method is computationally efficient. The perturbed Lambert’s problem, the relative motion of spacecraft, and the optimal control of spacecraft formation flight are solved. High-precision solutions are obtained with only a few iterations. A convergence analysis shows that the method converges for relatively long times of flight. For the spacecraft formation flight applications, the simulation results show that the method is applicable even for large interspacecraft separations of hundreds of kilometers.

Shock timing on the National Ignition Facility: The first precision tuning series

Ignition implosions on the National Ignition Facility (NIF) [Lindl et al., Phys. Plasmas 11 , 339 (2004)] are driven with a very carefully tailored sequence of four shock waves that must be timed to very high precision in order to keep the fuel on a low adiabat. The first series of precision tuning experiments on NIF have been performed. These experiments use optical diagnostics to directly measure the strength and timing of all four shocks inside the hohlraum-driven, cryogenic deuterium-filled capsule interior. The results of these experiments are presented demonstrating a significant decrease in the fuel adiabat over previously un-tuned implosions. The impact of the improved adiabat on fuel compression is confirmed in related deuterium-tritium (DT) layered capsule implosions by measurement of fuel areal density (ρR), which show the highest fuel compression (ρR ∼ 1.0 g/cm2 ) measured to date.

Precision on-board orbit model for attitude control of the advanced land observing satellite (ALOS)

A star-sensor-based attitude determination system estimates spacecraft attitude with respect to the inertial coordinate system. When a satellite equipped with the star-sensor-based attitude determination system implements geocentric pointing, it requires the satellite's position information relative to the Earth's center. Conventional Earth-pointing satellites carried only low-order on-board orbit models because of their Earth- sensor-based attitude determination systems and moderate attitude accuracy requirements. The Advanced Land Observing Satellite (ALOS), which has stringent attitude control accuracy and attitude stability requirements and therefore a star-sensor-based attitude determination system, carries a high-order precision on-board orbit model that has 15 parameters and accomplishes the required accuracy by frequent updates of those parameters. This paper presents the design of the on-board orbit model and its flight results. In addition, the attitude control errors and attitude stability performance that were induced by the attitude control reference generated by the orbit model are assessed.