Miracle-dz/UniFAR-FTUs huggingface dataset:
Improved inversion through use of the null space

Standard least-squares traveltime inversion techniques tend to produce smoothed estimates of the velocity field. More complete results can be obtained by incorporating into the inversion scheme a priori information about the media to be imaged, derived from well logs, core data, and surface geology. A promising technique for achieving this involves projecting this information onto the null space model singular vectors of the inverse problem and including this projection with the non-null space contribution in order to produce a solution. The method, demonstrated with both field and synthetic crosshole traveltime data acquired through layered, anisotropic media, successfully produces improved inversion solutions with lower traveltime residuals, layers that are more homogeneous, sharper interfaces, and better correlated anisotropy parameters than solutions obtained with standard techniques.
Sampled-data H ∞ control for a class of Markovian jump systems with input saturation via stochastic sampling design

This paper deals with the problem of H ∞ control for a stochastic sampling Markovian jump system subject to input saturation. The stochastic sampling we address is a Bernoulli distribution and two different sampling periods are considered whose occurrence probabilities are known constants. Actually the control method in this paper can be applied to a system with multiple stochastic sampling periods. By transforming the original stochastic sampling Markovian jump system into a continuous Markovian jump delayed systems, the plant can be stabilized by a state-feedback controller with input saturation. By applying an appropriate Lyapunov–Krasovskii function, some sufficient conditions for the stabilization of the system and the H ∞ controller design are derived in terms of linear matrix inequalities. Finally, in order to validate the efficiency of the approach mentioned above, a simulation example is provided.
Investigation of HZETRN 2010 as a Tool for Single Event Effect Qualification of Avionics Systems - Part II

NASA's future missions are focused on deep space for human exploration that do not provide a simple emergency return to Earth. In addition, the deep space environment contains a constant background Galactic Cosmic Ray (GCR) radiation exposure, as well as periodic Solar Particle Events (SPEs) that can produce intense amounts of radiation in a short amount of time. Given these conditions, it is important that the avionics systems for deep space human missions are not susceptible to Single Event Effects (SEE) that can occur from radiation interactions with electronic components. The typical process to minimizing SEE effects is through using heritage hardware and extensive testing programs that are very costly. Previous work by Koontz, et al. [1] utilized an analysis-based method for investigating electronic component susceptibility. In their paper, FLUKA, a Monte Carlo transport code, was used to calculate SEE and single event upset (SEU) rates. This code was then validated against in-flight data. In addition, CREME-96, a deterministic code, was also compared with FLUKA and in-flight data. However, FLUKA has a long run-time (on the order of days), and CREME-96 has not been updated in several years. This paper will investigate the use of HZETRN 2010, a deterministic transport code developed at NASA Langley Research Center, as another tool that can be used to analyze SEE and SEU rates. The benefits to using HZETRN over FLUKA and CREME-96 are that it has a very fast run time (on the order of minutes) and has been shown to be of similar accuracy as other deterministic and Monte Carlo codes when considering dose [2, 3, 4]. The 2010 version of HZETRN has updated its treatment of secondary neutrons and thus has improved its accuracy over previous versions. In this paper, the Linear Energy Transfer (LET) spectra are of interest rather than the total ionizing dose. Therefore, the LET spectra output from HZETRN 2010 will be compared with the FLUKA and in-flight data to validate HZETRN 2010 as a computational tool for SEE qualification by analysis. Furthermore, extrapolation of these data to interplanetary environments at 1 AU will be investigated to determine whether HZETRN 2010 can be used successfully and confidently for deep space mission analyses.
Population transfer by an amplitude-modulated pulse

We propose a technique for coherent population inversion of a two-state system, which uses an amplitude-modulated pulse. In the modulation-free adiabatic basis, the modulation introduces oscillating interaction between the adiabatic states. In a second rotating-wave approximation picture, this oscillating interaction induces a pair of level crossings between the energies of the adiabatic states if the modulation frequency is chosen appropriately. By suitably offsetting the modulation with respect to the center of the pulse, one can make the modulation act only in the vicinity of one of these crossings. In a higher-order adiabatic basis, this crossing shows up as an avoided crossing between the energies of the higher-order adiabatic states. As a result robust and efficient population transfer can be achieved between the adiabatic states, and hence, between the original bare states. We derive analytically the conditions on the interaction parameters for this technique and verify them with numerical simulations. Possible experimental implementations are discussed.
Disease resistance modelled as first‐passage times of genetically dependent stochastic processes

Summary. Mastitis resistance data on dairy cattle are modelled as first‐passage times of stochastic processes. Population heterogeneity is included by expressing process parameters as functions of shared random variables. We show how dependences between individuals, e.g. genetic relationships, can be exploited in the analyses. The method can be extended to handle situations with multiple hidden causes of failure. Markov chain Monte Carlo methods are used for estimation.
New identities and transformations for hardware power operators

In this work we present some improvements on hardware operators dedicated to the computation of power operations with fixed integer exponent (x3, x4, . . .) in unsigned radix-2 fixed-point or integer representations. The proposed method reduces the number of partial products using simplifications based on new identities and transformations. These simplifications are performed both at the logical and the arithmetic levels. The proposed method has been implemented in a VHDL generator that produces synthesizable descriptions of optimized operators. The results of our method have been demonstrated on FPGA circuits.
FUNDING A WARRANTY RESERVE WITH CONTRIBUTIONS AFTER EACH SALE

We consider funding an interest-bearing warranty reserve with contributions after each sale. The problem for the manufacturer is to determine the initial level of the reserve fund and the amount to be put in after each sale, so as to ensure that the reserve fund covers all of the warranty liabilities with a prespecified probability over a fixed period of time. We assume a nonhomogeneous Poisson sales process, random warranty periods, and a constant failure rate for items under warranty. We derive the mean and variance of the reserve level as a function of time and provide a robust heuristic to aid the manufacturer in its decision.
Theoretical investigation on 3rd harmonic voltage in inductive measurements of critical current density in superconducting films

We have theoretically investigated third-harmonic voltage detected in a widely-used inductive measurement of critical current density J/sub c/ in superconducting films. In the inductive measurement, an ac drive current I/sub 0/ cos /spl omega/t flows in a small coil close to the surface of a superconducting film, and third-harmonic voltage V/sub 3/ cos(3/spl omega/t + /spl theta//sub 3/) induced in the coil is detected. The relationships among the ac drive current I/sub 0/, the amplitude V/sub 3/, and the phase /spl theta//sub 3/ of the third-harmonic voltage are derived on the bases of the critical state model. When the drive current is smaller than a threshold value I/sub c0/, the third-harmonic voltage is near zero, V/sub 3/ /spl ap/ 0 for I/sub 0/ I/sub c0/, on the other hand, the third-harmonic voltage is expressed as V/sub 3/ exp(-i/spl theta//sub 3/) = /spl omega/I/sub c0/ G/sub 3/(I/sub 0//I/sub c0/), where G/sub 3/(/spl gamma/) is a scaling function determined by the configuration of the coil. The predicted scaling law of V/sub 3//I/sub c0/ and /spl theta//sub 3/ as functions of I/sub 0//I/sub c0/ is clearly observed in an YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// film.
Statistical Design and Analysis of Experiments

Linear Models and Quadratic Forms Experiments With a Single Factor Experiments With Two Factors Experiments With Several Factors Latin Square Designs Factors With Two or Three Levels Fractions of 2n Factorial Designs Fractional Factorials With More Than Two Levels Response Surfaces Incomplete Block Designs Partially Balanced Incomplete Block Designs The Existence and Construction of Balanced Incomplete Block Designs The Existence and Construction of Partially Balanced Designs Additional Topics in Partially Balanced Designs Appendix - Matrices and Quadratic Forms.
Development of selective lateral photoelectrochemical etching of InGaN/GaN for lift-off applications

The authors have developed a wet band gap-selective photoelectrochemical etching process to produce deep undercuts (∼500 μm) into InGaN/GaN heterostructures. These undercuts were used in a lift-off process which successfully transferred device-scale (100 μm diameter, 5 μm thick) disks from their underlying sapphire substrates to another substrate. Experiments were conducted using a lamp-and-filter arrangement, employing n-type and p-type GaN pieces as filters. Polishing was conducted to smooth the resulting substrate-transferred GaN disks.
Robust-tracking control for robot manipulator with deadzone and friction using backstepping and RFNN controller

This study deals with a robust non-smooth non-linearity compensation scheme for the direct-drive robot manipulator with an asymmetric deadzone, dynamic friction in joints and between the environmental contact space and end-effector and uncertainty. A model-free recurrent fuzzy neural network (RFNN) control system to approximate the ideal backstepping control law is designed to replace the traditional model-based adaptive controller, which requires information on the robots dynamics in advance. The simple dead-zone estimator and friction compensator based on the elasto-plastic friction model are developed in order to estimate unknown dead-zone width and friction parameters. The Lyapunov stability analysis yields the adaptive laws of the RFNN controller as well as the estimators of a dead-zone width and an elasto-plastic friction parameter. The validity of the proposed control scheme is confirmed from simulated results for free and constrained direct-drive robots with a deadzone in joint actuator, dynamic friction in joints and contact surfaces of the end-effector and uncertainty.
A WWW-based tool for the remote optimization of electromagnetic devices

In this paper, a World Wide Web-based tool for the remote definition and analysis of optimization problems in electromagnetic design is described. The tool can find effective applications both in advanced teaching and in industrial design activities, thanks to its user-friendliness. The architecture of the system and its current implementation, based on commonly available tools, are presented and discussed in detail. Examples of the use of the tool for the design of a magnet to be used in high energy physics experiments and a simple electromagnetic actuator are given.
Regional sensitivity comparison between optical and acousto-optic sensing

Optical systems based on near infrared spectroscopy probe biological tissue oxygenation of a relatively large region. The acousto-optic (AO) method can tag photons by focused ultrasound in a region of interest within the tissue for potential localized oxygenation sensing. This study aimed to compare the regional sensitivity between the optical and AO sensing techniques. The regional sensitivity was defined as the amount of change observed in the measured signal in response to a small localized change in the optical absorption. In both reflection and transmission configurations, optical systems based on a single source and detector have been shown to be more sensitive to the absorption variation in the superficial region. The results demonstrate that the AO sensitivity region depends on the location of the ultrasound focal region as well as the distribution of the optical fluence. In the transmission mode, the optimal AO sensitivity region has been found to be in the ultrasound focal region. In the reflection mode, however, the optimal sensitivity region of AO does not always coincide with the location of the ultrasound focal region. Instead, the AO measurement is also sensitive to the local absorption change in regions between the ultrasound focal region and the optical probes. In general, the AO method can probe deeper into the phantom as compared to the optical measurements.
Theoretical determination of K1(1270,1400) mixing angle in QCD

In quark model, the strange axial vector mesons K1(1270) and K1(1400) are defined as the mixtures of orbital angular momentum states K1A and K1B. In this work, by using the orthogonality of the mass eigenstates, we have estimated the K1(1270, 1400) mixing angle θK1, where we have found that θK1 ≃ −(39 ± 4)°.
A new method for evaluating two-loop Feynman integrals and its application to Higgs production

A complete set of master integrals for describing the gluon fusion process gg → h at two-loop order in the Standard Model, SM, is identified. All master integrals are computed as Laurent series in the dimensional regularization parameter in terms of harmonic polylogarithms. The gg → h amplitude in the SM is reduced to the master integrals, leading to a closed analytic formula for the amplitude, which is in agreement with the known result. The reduction procedure is repeated for the SM-like amplitude, where a heavy scalar instead of the quark is running in the loops. This yields a new result. The complete set of master integrals also allows automated computation of gg → h contributions in any extension of the SM, as long as only a single mass parameter occurs in the loops, as well as other processes with similar kinematics. Then it is shown how to use the technique of contour deformation for handling thresholds within the framework of sector decomposition. This leads to the first known numerical method capable of evaluating in principle arbitrary tensor Feynman diagrams with UV, IR and threshold singularities in arbitrary kinematic regions. The power of this method is demonstrated by computing the full virtual supersymmetric QCD amplitude for gg → h,H at two-loop order in the Minimal Supersymmetric Standard Model, MSSM. This includes two-loop diagrams containing up to five different kinematic invariants, which are clearly beyond the scope of any known analytic technique. The integration succeeds even in the numerically challenging case, where the kinematic invariants have extremely disparate values, reaching ratios of 104. It is reasonable to assume, that the numerical method presented is capable of evaluating the two-loop gg → h amplitude in any conceivable extension of the SM. It thus eliminates the awkward situation, that the important NLO QCD corrections to the basic LHC process gg → h were not computable in viable extensions of the SM, like the MSSM. The method is clearly not limited to 2→ 1 kinematics and yields a flexible tool for checking analytic results as well as for direct numerical computations in perturbative quantum field theory.
TESTING THE FOUNDATIONS OF RELATIVITY USING CRYOGENIC OPTICAL RESONATORS

We present a new generation of experiments using cryogenic optical resonators(COREs) to test the foundations of relativity. The experiments test the isotropy of the speed of light (Michelson-Morley experiment), the independece of the speed of light from the velocity of the laboratory (Kennedy-Thorndike experiments), and the gravitational redshift for clocks based on an electronic transition. Compared with the best previous results, our tests have already yielded improvements up to a factor of three. Future versions promise significant improvements.
Dynamic fuzzy control and system stability for the Acrobot

This paper discusses the swing-up control of a two link robot mechanism known as the Acrobot. Previously, a technique using meta-rules was proposed to compensate for external disturbances when using a dynamic fuzzy controller. In this paper, stability of the meta-rule system is analyzed from a global asymptotic stability viewpoint based on fuzzy characteristic matrices. These matrices are generated from the first phase of a three phase learning process involving the combination of genetic algorithms, dynamic switching fuzzy systems, and meta-rule techniques with the purpose of developing a better performing fuzzy controller.
Remote Sensing of the Sea Surface

the sea surface provide means for measuring the spatial characteristics of surface waves and the spatial distributions of surface and near-surface oceanic properties over a large area at, in essence, one instant of time. As the techniques have developed, the oceanographer and the marine meteorologist have been provided wit h new sets of eyes that have not only enabled old questions to be answered but have also uncovered a rich set of new phenomena, some imperfectly understood, of ocean current and eddy structure, wave-current inter­ actions, and air-sea interactions more generally. The ability to measure sea­ surface properties without in situ instrumentation enables rapid surveys to be made of sea-surface temperature distributions and ice characteristics, as well as of the distributions of ocean-surface winds, which are so impor­ tant an input to continental and regional weather prediction. The pioneers of remote sensing of the ocean surface were certainly Cox & Munk (1954a,b) and Pierson (1962). In their celebrated study of Sun glitter patterns, Cox & Munk provided the first systematic measurements of the roughness of the sea surface-the components of mean square slope, their probability distributions, and their variations with wind speed. Pierson's stereophotograph ic measurements from two aircraft [the Stereo Wave Observation Project (SWOP)] sampled the sea-surface configuration at several instants in time, which allowed the first direct measurements of the two-dimensional wave spectrum. Simple (and not so simple) optical techniques are still useful in preserving a record of what the eye can see or in recording what happens too fast for the eye to see. Photography from the Earth Resources Technology Satellite (ERTS-I) and from the Space
TESTS OF COMMON STOCHASTIC TRENDS

This paper is concerned with tests in multivariate time series models made up of random walk (with drift) and stationary components. When the stationary component is white noise, a Lagrange multiplier test of the hypothesis that the covariance matrix of the disturbances driving the multivariate random walk is null is shown to be locally best invariant, something that does not automatically follow in the multivariate case. The asymptotic distribution of the test statistic is derived for the general model. The test is then extended to deal with a serially correlated stationary component. The main contribution of the paper is to propose a test of the validity of a specified value for the rank of the covariance matrix of the disturbances driving the multivariate random walk. This rank is equal to the number of common trends, or levels, in the series. The test is very simple insofar as it does not require any models to be estimated, even if serial correlation is present. Its use with real data is illustrated in the context of a stochastic volatility model, and the relationship with tests in the cointegration literature is discussed.
Analysis of rippled shock-wave propagation and ablation-front stability by theory and hydrodynamic simulation

The hydrodynamic start-up problem is one of the most crucial issues in laser-driven symmetrical implosion. The target-surface roughness and initial imprint by nonuniform laser irradiation result in Rayleigh–Taylor instability in the acceleration and deceleration phase. To estimate the tolerance of the target-surface roughness, the temporal behaviour of corrugated ablation surface and rippled shock-wave propagation are investigated using a perturbation analysis of the fluid equation, which is solved under the boundary model of a fire-polished ablation surface. The results show good agreement with two- dimensional hydrodynamic simulation and experimental results [T. Endo et al., Phys. Rev. Lett. 74, 3608 (1995)].
Real-time spectroscopic evaluation of oral lesions and comparisons with histopathology

Optical techniques including widefield autofluorescence and reflectance imaging, depth-sensitive optical spectroscopy, and high-resolution imaging can be used to noninvasively detect dysplastic and cancerous alterations in oral tissue. The diagnostic performance of depth-sensitive optical spectroscopy with respect to histopathology is examined. A compact, portable spectroscopy device for clinical use is described. Practical considerations for the comparison of optical measurements to histopathologic diagnoses are outlined. Important considerations for comparison to histopathology include the physical correspondence of the measured region to the biopsy or specimen; data collection and processing procedures; and data analysis procedures. Multimodal combinations of widefield imaging, point spectroscopy, and highresolution imaging may enhance the ability of clinicians to accurately assess the margins of neoplastic oral lesions in vivo.
Lagrangian finite element method for free surface Navier-Stokes flow using fractional step methods

This paper presents a finite element analysis based on the Lagrangian description for unsteady incompressible viscous fluid flow with a free surface. The behaviour of the fluid is expressed by the unsteady Navier-Stokes equation. For numerical integration in time the fractional step method is used. This method is useful because one can use the same linear interpolation functions for both velocity and pressure. In this paper, four variations of the fractional step method are presented and the numerical results are compared. To confirm the effectiveness of these methods, solitary wave propagation is analysed.
Analysis of Resolved and Parameterized Vertical Transports in Convective Boundary Layers at Gray-Zone Resolutions

AbstractThe gray zone of a physical process in numerical models is defined as the range of model resolution in which the process is partly resolved by model dynamics and partly parameterized. In this study, the authors examine the grid-size dependencies of resolved and parameterized vertical transports in convective boundary layers (CBLs) for horizontal grid scales including the gray zone. To assess how stability alters the dependencies on grid size, four CBLs with different surface heating and geostrophic winds are considered. For this purpose, reference data for grid-scale (GS) and subgrid-scale (SGS) fields are constructed for 50–4000-m mesh sizes by filtering 25-m large-eddy simulation (LES) data.As relative importance of shear increases, the ratio of resolved turbulent kinetic energy increases for a given grid spacing. Vertical transports of potential temperature, momentum, and a bottom-up diffusion passive scalar behave in a similar fashion. The effects of stability are related to the horizontal sca.