cssi/SciSciGPT-SciSciNet huggingface dataset:
Nonlinear properties of split-ring resonators.

In this letter, the properties of split-ring resonators (SRRs) loaded with high-Q capacitors and nonlinear varactors are theoretically analyzed and experimentally measured. We demonstrate that the resonance frequency fm of the nonlinear SRRs can be tuned by increasing the incident power. fm moves to lower and higher frequencies for the SRR loaded with one varactor and two back-to-back varactors, respectively. For high incident powers, we observe bistable tunable metamaterials and hysteresis effects. Moreover, the coupling between two nonlinear SRRs is also discussed.
EQUIVALENCE OF GEOMETRIC h 25 APPROACHES TO TWO-DIMENSIONAL QUANTUM GRAVITY

We show the equivalence between the standard weak coupling regime c>25 of the two-dimensional quantum gravity and regime h<1/2 of the original geometric approach of Polyakov,1,2 developed in Refs. 3–5.
Personality preferences in laboratory economics experiments

Abstract Student volunteers at the U.S. Naval Academy (USNA) participated in one of the following one-shot games: a dictator game, an ultimatum game, a trust game, or a prisoner's dilemma game. We find limited support for the importance of personality type for explaining subjects’ decisions. With controls for personality preferences, we find little evidence of behavioral differences between males and females. Furthermore, we conclude that seniority breeds feelings of entitlement—seniors at USNA generally exhibited the least cooperative or other-regarding behavior.
The Heterogeneity of Self-Employment: The Example of Asians in the United States

Self-employment rates differ widely across industries and across racial and ethnic categories. The heterogeneity of self-employment is most pronounced among Asians working in the U.S. The self-employment rate of Koreans is almost eight times greater than the self-employment rate of Laotians. This paper examines the pattern of self-employment across more narrowly defined classifications of Asians and industries to illustrate the heterogeneity of self-employment, and discusses the implications of this heterogeneity.
Kinetic Analysis of Combustion Synthesis of Lead Magnesium Niobate from Metal Carboxylate Gels

A combustion synthesis route was developed for direct crystallization of perovskite lead magnesium niobate (PMN) from metal carboxylate gels. Direct PMN formation is attributed to a homogeneous cation distribution in the gel and the rapid heating during exothermic gel decomposition in oxidizing atmospheres. The maximum bed temperature and gel decomposition rate are determined by the combined influence of chemical kinetics, heat, and mass transfer. It is shown that there is a temperature window between 700° and 750°C which favors direct PMN formation, whereas pyrochlore formation is favored below 650°C and PbO volatilization occurs above 800°C. The effects of kinetic and transport parameters including oxygen partial pressure, gas flow rate, and bed geometry on PMN formation are discussed on the basis of a thermal ignition model for heterogeneous reactions.
The Matrix Formulation of Type IIB Five-Branes

Abstract We present a matrix model which interpolates between type IIA and type IIB NS five-branes. The matrix description involves a three-dimensional bulk quantum field theory interacting with impurities localized in one spatial direction. We obtain a dual matrix formulation for the exotic six-dimensional theory on coincident type IIB NS five-branes by studying the T -dual description in terms of Kaluza-Klein monopoles in type IIA string theory. After decoupling the bulk physics, the matrix description reduces to the conformal field theory of the Coulomb branch for the type IIA matrix string propagating on certain singular spaces. In many ways, this dual realization of superconformal theories is the two-dimensional analog of three-dimensional mirror symmetry.
Energy and Exergy Analyses of the Pulse Detonation Engine

Energy and exergy analyses have been performed on a pulse detonation engine. A pulse detonation engine is a promising new engine, which uses a detonation wave instead of a deflagration wave for the combustion process. The high-speed supersonic combustion wave reduces overall combustion duration resulting in an nearly constant volume energy release process compared to the constant pressure process of gas turbine engines. Gas mixture in a pulse detonation engine has been modeled to execute the Humphrey cycle. The cycle includes four processes: isentropic compression, constant volume combustion, isentropic expansion, and isobaric compression. Working fluid is a fuel-air mixture for unburned gases and products of combustion for burned gases. Different fuels such as methane and JP10 have been used. It is assumed that burned gases are in chemical equilibrium states. Both thermal efficiency and effectiveness (exergetic efficiency) have been calculated for the pulse detonation engine and simple gas turbine engine. Comparison shows that for the same pressure ratio pulse detonation engine has better efficiency and effectiveness than the gas turbine system.
In vitro erbium: YAG laser lithotripsy

The potential application of an Erbium:YAG (Er:YAG) laser (Q 0 = 50 mJ/pulse; τ p = 275 μs; rep. rate = 2, 10 Hz) with a sapphire delivery fiber for intracorporeal laser lithotripsy was explored. Preliminary measurements on calculus mass-loss and fragmentation efficiency were conducted and results were compared with that of Ho:YAG laser lithotripsy. Laser induced bubble and lithotripsy dynamics were investigated to assess the mechanism(s) involved in the fragmentation process. Results showed that the fragmentation efficiency (mass-loss/H o - g.μm 2 /J) in Er:YAG laser lithotripsy was about 2.4 times that of Ho:YAG laser lithotripsy (used: Q 0 = 500 mJ/pulse; Tp = 250 μs; rep. rate = 10 Hz). Acoustic transients were found to have minimal effect during Er:YAG laser lithotripsy. Schlieren flash images suggested a predominantly photothermal mechanism due to direct laser energy absorption, which resulted in recrystallization and plume formation. These events indicated melting and chemical decomposition of the calculus composition. Another observation led to the possibility of a plasma-mediated photothermal mechanism. The 'Moses effect' facilitating pulsed mid-infrared laser delivery appeared more efficient for the Er:YAG laser than for the Ho:YAG laser. With the sapphire fiber, experimental results suggested the potential of an improved treatment modality by the Er:YAG laser for intracorporeal laser lithotripsy.
Baby morse theory in data analysis

A methodology is proposed for inferring the topology underlying point cloud data. The approach employs basic elements of Morse Theory, and is capable of producing not only a point estimate of various topological quantities (e.g., genus), but it can also assesses their sampling uncertainty in a probabilistic fashion. Several examples of point cloud data in three dimensions are utilized to demonstrate how the method yields interval estimates for the topology of the data as a 2-dimensional surface embedded in R3.
Calorie Elasticities with Income Dynamics: Evidence from the Literature

This paper proposes a finite mixture model to identify the behavioral transition of calorie consumption with an assumption that nutrition consumption is a mixture of behaviors in two different stages: a poor stage and an affluent stage. Based on a meta-analysis of 387 calorie-income elasticities collected from 90 primary studies, it is found that the threshold income for calorie demand transition is $460 in 2012 prices. This implies that the transitional threshold for calorie consumption is $1.26/day, which is slightly lower than the World Bank's poverty line ($1.25/day in 2005 purchasing power parity prices) after deflation. This study provides a new empirical approach to evaluate the transition of calorie consumption and poverty line.
Measurable rigidity of actions on infinite measure homogeneous spaces, II

We consider the problems of measurable isomorphisms and join- ings, measurable centralizers and quotients for certain classes of ergodic group actions on infinite measure spaces. Our main focus is on systems of algebraic origin: actions of lattices and other discrete subgroups < G on homoge- neous spaces G/H where H is a sufficiently rich unimodular subgroup in a semi-simple group G. We also consider actions of discrete groups of isometries < Isom(X) of a pinched negative curvature space X, acting on the space of horospheres Hor(X). For such systems we prove that the only measurable isomorphisms, joinings, quotients etc. are the obvious algebraic (or geometric) ones. This work was inspired by the previous work of Shalom and Steger, but uses completely different techniques which lead to more general results. 1. Introduction and Statement of the Main Results
Diastereoselective liquid assisted grinding: ‘cracking’ functional resins to advance chromatography-free synthesis

As regulations that restrict the use of organic solvents become more stringent, ball milling remains an attractive substitute for traditional organic synthesis. However, the mechanochemistry community does not have a purification pathway to complement the solvent-free, ball milling process. Functional resins have proven to be powerful synthetic tools that simplify purification, but traditional handling of these resins restricts their utility, as hazardous organic solvents are needed to swell the resin. Ball milling the functional resin exposes the functional groups as a function of surface area. This report details the use of ball milling and functional resins to perform an environmentally attractive version of the Wittig reaction.
Chromophore binding to in vitro engineered bio-mimetic surfaces

In the retina, a chromophore isomerizes and the protein to which it binds changes shape. In this proof-of-concept experiment we engineer an artificial surface to mimic the physiochemical environment of the retina and the key reaction of the visual cycle. We immobilized small peptides on silicon and assessed changes in their surface properties upon chromophore binding via ellipsometry, X-ray photoelectron spectroscopy and atomic force microscopy. Our observations suggest that when binding occurs it is accompanied by changes in the properties of the film composed of surface-anchored peptides.
A discussion on mean excess plots

The mean excess plot is a tool widely used in the study of risk, insurance and extreme values. One use is in validating a generalized Pareto model for the excess distribution. This paper investigates some theoretical and practical aspects of the use of the mean excess plot.
Random matrices and the spectrum of N-flation

N-flation is a promising embedding of inflation in string theory in which many string axions combine to drive inflation. We characterize the dynamics of a general N-flation model with nondegenerate axion masses. Although the precise mass of a single axion depends on compactification details in a complicated way, the distribution of masses can be computed with very limited knowledge of microscopics: the shape of the mass distribution is an emergent property. We use random matrix theory to show that a typical N-flation model has a spectrum of masses distributed according to the Marcenko–Pastur law. This distribution depends on a single parameter, the number of axions divided by the dimension of the moduli space. We use this result to describe the inflationary dynamics and phenomenology of a general N-flation model. We produce an ensemble of models and use numerical integration to track the axions' evolution and the resulting scalar power spectrum. For realistic initial conditions, the power spectrum is considerably more red than in single-field m22 inflation. We conclude that random matrix models of N-flation are surprisingly tractable and have a rich phenomenology that differs in testable ways from that of single-field m22 inflation.
Modeling the Effects of the PCB Motion on the Response of Microstructures Under Mechanical Shock

Microelectomechanical systems (MEMS) are often used in portable electronic products that can be subjected to mechanical shock or impact due to being dropped accidentally. This work presents a modeling and simulation effort to investigate the effect of the vibration of a printed circuit board (PCB) on the dynamics of MEMS microstructures when subjected to shock. Two models are presented. In the first approach, the PCB is modeled as an Euler-Bernoulli beam to which a lumped model of a MEMS device is attached. In the second approach, a special case of a cantilever microbeam is modeled as a distributed-parameter system, which is attached to the PCB. These lumped-distributed and distributed-distributed models are solved numerically by integration of the equation of motion over time using the Galerkin procedure. Results of the two models are compared against each other for the case of a cantilever microbeam and also compared to the predictions of a finite-element model using ANSYS. The influence of the higher order vibration modes of the PCB, the location of the MEMS device on the PCB, the electrostatic forces, damping, and shock pulse duration are presented. It is found that neglecting the effects of the higher order modes of the PCB and the location of the MEMS device can cause incorrect predictions of the response of the microstructure and may lead to failure of the MEMS device. It is observed from the results that in some cases, depending on the different parameters of the problem, the response of the microstructure can be amplified causing early dynamic pull-in and hence possibly failure of the device.
Observational probes of cosmic acceleration

The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of “dark energy” with exotic physical properties, or that Einstein’s theory of gravity breaks down on cosmological scales. The profound implications of cosmic acceleration have inspired ambitious efforts to understand its origin, with experiments that aim to measure the history of expansion and growth of structure with percent-level precision or higher. We review in detail the four most well established methods for making such measurements: Type Ia supernovae, baryon acoustic oscillations (BAO), weak gravitational lensing, and the abundance of galaxy clusters. We pay particular attention to the systematic uncertainties in these techniques and to strategies for controlling them at the level needed to exploit “Stage IV” dark energy facilities such as BigBOSS, LSST, Euclid, and WFIRST. We briefly review a number of other approaches including redshift-space distortions, the Alcock–Paczynski effect, and direct measurements of the Hubble constant H_0. We present extensive forecasts for constraints on the dark energy equation of state and parameterized deviations from General Relativity, achievable with Stage III and Stage IV experimental programs that incorporate supernovae, BAO, weak lensing, and cosmic microwave background data. We also show the level of precision required for clusters or other methods to provide constraints competitive with those of these fiducial programs. We emphasize the value of a balanced program that employs several of the most powerful methods in combination, both to cross-check systematic uncertainties and to take advantage of complementary information. Surveys to probe cosmic acceleration produce data sets that support a wide range of scientific investigations, and they continue the longstanding astronomical tradition of mapping the universe in ever greater detail over ever larger scales.
Structure and Conductivity of Tetragonal and Rhombohedral Lanthanum Oxyfluoride Compounds

Lanthanum oxyfluoride compounds can form on the electrodes of oxygen sensors, so transport through these compounds can affect sensor performance. At high temperatures, lanthanum oxyfluoride forms a cubic fluorite structure, which orders into either a tetragonal or rhombohedral structure during cooling. In this paper, results on the structure and conductivity of lanthanum oxyfluoride compounds with different ordered structures (tetragonal and rhombohedral) and compositions (x = 0–0.75) are reported. X‐ray powder diffraction results indicate that the value of x in tetragonal ranges from 0 to 0.43. Impedance spectroscopy results indicate that the minimum conductivity occurs near the stoichiometric LaOF composition (i.e., x = 0), where the fewest anion point defects are present. © 2000 The Electrochemical Society. All rights reserved.
Theoretical aspects of gamma-ray bursts

Cosmological GRBs are discussed with an emphasis on their plausible connection with black holes. GRBs can be triggered by collapse of stellar-mass objects that leads to formation of a black hole and a transient debris disk with a huge accretion rate. The disk is believed to produce a relativistic jet ("fireball") that expands and emits to infinity the observed burst of gamma-rays. This accretion-jet picture is similar to quasars and X-ray binaries, however, there are important differences: the physical conditions and the cooling mechanism in the disk are very different. The observed radiation is emitted when the expanding fireball becomes transparent, at distances much larger than the Schwarzschild radius. The burst is then observed as a powerful relativistic explosion and the transient accretion disk in its center serves as a brief source of energy that drives the explosion. The explosion picture depends on the fireball nuclear composition which is shaped close to the black hole. A large amount of free neutrons survive till the emission phase and link the physics of the central engine to observed radiation.
Systematic Process Analysis: when and how to use it

Challenging the contention that statistical methods applied to large numbers of cases invariably provide better grounds for causal inference, this article explores the value of a method of systematic process analysis that can be applied in a small number of cases. It distinguishes among three modes of explanation – historically specific, multivariate and theory-oriented – and argues that systematic process analysis has special value for developing theory-oriented explanations. It outlines the steps required to perform such analysis well and illustrates them with reference to Owen's investigation of the ‘democratic peace’. Comparing the results available from this kind of method with those from statistical analysis, it examines the conditions under which each method is warranted. Against conceptions of the ‘comparative method’, which imply that small-n case-studies provide weak grounds for causal inference, it argues that the intensive examination of a small number of cases can be an appropriate research design for testing such inferences.
Central limit theorems for random polytopes in a smooth convex set

Let K be a smooth convex set with volume one in . Choose n random points in K independently according to the uniform distribution. The convex hull of these points, denoted by Kn, is called a random polytope. We prove that several key functionals of Kn satisfy the central limit theorem as n tends to infinity.
Post-choice revaluation of hedonic preferences: insights from functional imaging.

For the pairs that had initially been rated dispar ately, there was no change in the rat-ings post-choice.Despite the lack of differences in rat-ings pre-choice, neuroimaging revealed a region in the caudate nucleus that tracked preference for the selected option even before revaluation was induced by the decision (Sharot et al. 2009, Figure 3b). The authors also demonstrated a further increase in activation for the selected option over rejected option post-choice within the right caudate ( Sharot et al. 2009 , Figure 3c). Finally, the post-choice increase in activa-tion difference between the selected and
Asynchronous finite-state machines - A novel control system class.

Asynchronous finite state sequential nonlinear controller synthesis with few flip-flops for dynamic space vehicle systems
Where Computer Security Meets National Security

This paper identifies two conceptions of security in contemporary concerns over the vulnerability of computers and networks to hostile attack. One is derived from individual-focused conceptions of computer security developed in computer science and engineering. The other is informed by the concerns of national security agencies of government as well as those of corporate intellectual property owners. A comparative evaluation of these two conceptions utilizes the theoretical construct of "securitization,"developed by the Copenhagen School of International Relations.
Sharp growth estimates for dyadic $b$-input $T(b)$ theorems

The following deals with the $T(b)$ theorems of David, Journe, and Semmes [7] considered in a dyadic setting. We find sharp growth estimates for a global and a local dyadic $T(b)$ Theorem. We use multiscale analysis and Haar wavelets in the local case.
The binary floating point digital differential analyzer

Twenty years ago the digital differential analyzer, DDA, was developed to replace the analog computer in the solution of differential equations. Although the DDA is slower than the analog computer, the DDA is capable of more accurate results since its accuracy is not bounded by its component characteristics. The cost of solving differential equations with the DDA is quite low compared with other methods such as a general purpose machine, since the DDA is a more simple device.
Topological relics of symmetry breaking: winding numbers and scaling tilts from random vortex–antivortex pairs

I show that random distributions of vortex–antivortex pairs (rather than of individual vortices) lead to scaling of typical winding numbers &#x1d4b2; trapped inside a loop of circumference &#x1d49e; with the square root of that circumference, , when the expected winding numbers are large, |&#x1d4b2;| ≫ 1. Such scaling is consistent with the Kibble–Zurek mechanism (KZM), with 〈&#x1d4b2;2〉 inversely proportional to , the typical size of the domain that can break symmetry in unison. (The dependence of on quench rate is predicted by KZM from critical exponents of the phase transition.) Thus, according to KZM, the dispersion scales as for large &#x1d4b2;. By contrast, a distribution of individual vortices with randomly assigned topological charges would result in the dispersion scaling with the square root of the area inside &#x1d49e; (i.e., ).Scaling of the dispersion of &#x1d4b2; as well as of the probability of detection of non-zero &#x1d4b2; with &#x1d49e; and can be also studied for loops so small that non-zero windings are rare. In this case I show that dispersion varies not as , but as , which results in a doubling of the scaling of dispersion with the quench rate when compared to the large |&#x1d4b2;| regime. Moreover, the probability of trapping of non-zero &#x1d4b2; becomes approximately equal to 〈&#x1d4b2;2〉, and scales as . This quadruples—as compared with valid for large &#x1d4b2;—the exponent in the power law dependence of the frequency of trapping of |&#x1d4b2;| = 1 on when the probability of |&#x1d4b2;| > 1 is negligible. This change of the power law exponent by a factor of four—from for the dispersion of large &#x1d4b2; to for the frequency of non-zero &#x1d4b2; when |&#x1d4b2;| > 1 is negligibly rare—is of paramount importance for experimental tests of KZM.
Reachable domain for interception at hyperbolic speeds

Abstract The interception of an ICBM at low altitude and in a short time requires hyperbolic speeds. At the acquisition time t0, if updated information about the trajectory of the target dictates a velocity correction for the interception, then it is of interest to assess the potential for interception. The reachable surface is defined as the boundary of the set of all attainable points at a given time t, for a fuel potential, conveniently expressed in terms of the Δv available. Properties of this surface are derived and its mathematical characterization is obtained. As an application of the concept, a necessary condition for a successful interception of a target given in terms of a capture function is explicitly derived.
Population uncertainty and Poisson games

A general class of models is developed for analyzing games with population uncertainty. Within this general class, a special class of Poisson games is defined. It is shown that Poisson games are uniquely characterized by properties of independent actions and environmental equivalence. The general definition of equilibrium for games with population uncertainty is formulated, and it is shown that the equilibria of Poisson games are invariant under payoff-irrelevant type splitting. An example of a large voting game is discussed, to illustrate the advantages of using a Poisson game model for large games.
New and concise syntheses of the bicyclic oxamazin core using an intramolecular nitroso Diels-Alder reaction and ring-closing olefin metathesis.

Herein two new and concise synthetic approaches for making an unsaturated bicyclic oxamazin core are reported. The first involves the use of an intramolecular Diels–Alder reaction to form both of the fused rings in one step. The second approach incorporates ring-closing olefin metathesis in the final step to form the second fused ring of the core. The scope of the second approach was also expanded further to afford larger ringed bicyclic systems.
A new, stereoselective synthesis of methyl 1,2-trans-1-thioglycosides

Abstract Per-0-acetylated glycopyranoses were converted by methylthiotrimethylsilane in the presence of boron trifluoride or trimethylsilyl trifluoromethanesulfonate to the corresponding methyl 1,2- trans -1-thioglycopyranosides in a highly stereoselective process.
Principles and applications of GFT projection NMR spectroscopy.

The two defining features of G-matrix Fourier transform (GFT) projection NMR spectroscopy are (i) repeated joint sampling of several indirect chemical shift evolution periods of a multidimensional NMR experiment so that transfer amplitudes are generated which are proportional to all possible permutations of cosine and sine modulations of the individual shifts, and (ii) linear combination of the subspectra resulting from such repeated joint sampling in the time or frequency domain which yields edited subspectra containing signals encoding phase-sensitively detected linear combinations of the jointly sampled shifts. This review sketches the underlying principles of GFT NMR and outlines its relation to further developments such as the reconstruction of multidimensional NMR spectra. Copyright © 2006 John Wiley & Sons, Ltd.
Asymmetric Tandem Wittig Rearrangement/Aldol Reactions

A new method for the asymmetric synthesis of α-alkyl-α,β-dihydroxy esters that involves tandem Wittig rearrangement/aldol reactions of O-benzyl- or O-allylglycolate esters derived from 2-phenylcyclohexanol is described. This sequence constructs two C−C bonds and two stereocenters, one of which is quaternary, to afford syn diol products with excellent stereocontrol. Cleavage of the chiral auxiliary affords enantiomerically enriched products with up to 95% ee. The application of this method to the preparation of a key intermediate in the synthesis of the antifungal agent alternaric acid is also described.
Imaging X-Ray, Optical, and Infrared Observations of the Transient Anomalous X-Ray Pulsar XTE J1810–197

We report X-ray imaging, timing, and spectral studies of XTE J1810-197, a 5.54 s pulsar discovered by Ibrahim and coworkers in recent Rossi X-Ray Timing Explorer (RXTE) observations. In a set of short exposures with the High Resolution Camera on board the Chandra X-Ray Observatory, we detect a strongly modulated signal (55% ± 4% pulsed fraction) with the expected period located at (J2000) 18h09m5108, -19°43'517, with a uncertainty radius of 06 (90% confidence level). Spectra obtained with XMM-Newton are well fitted by a two-component model that typically describes anomalous X-ray pulsars (AXPs), an absorbed blackbody plus power law with parameters kT = 0.67 ± 0.01 keV, Γ = 3.7 ± 0.2, NH = (1.05 ± 0.05) × 1022 cm-2, and FX(0.5-10 keV) = 3.98 × 10-11 ergs cm-2 s-1. Alternatively, a two-temperature blackbody fit is just as acceptable. The location of CXOU J180951.0-194351 is consistent with a point source seen in archival Einstein, ROSAT, and ASCA images, when its flux was nearly 2 orders of magnitude fainter, and from which no pulsations are found. The spectrum changed dramatically between the "quiescent" and "active" states; the former can be modeled as a softer blackbody. Using XMM-Newton timing data, we place an upper limit of 0.03 lt-s on any orbital motion in the period range 10 minutes-8 hr. Optical and infrared images obtained on the SMARTS 1.3 m telescope at the Cerro Tololo Inter-American Observatory (CTIO) show no object in the Chandra error circle to limits V = 22.5, I = 21.3, J = 18.9, and K = 17.5. Together, these results argue that CXOU J180951.0-194351 is an isolated neutron star, one most similar to the transient AXP AX J1844.8-0256. Continuing study of XTE J1810-197 in various states of luminosity is important for understanding and possibly unifying a growing class of isolated, young neutron stars that are not powered by rotation.
Bures metrics for certain high-dimensional quantum systems

Abstract Hubner's formula for the Bures (statistical distance) metric is applied to both a one-parameter and a two-parameter series ( n = 2,…,7) of sets of 2 n × 2 n density matrices. In the doubly -parameterized series, the sets are comprised of the n -fold tensor products - corresponding to n independent, identical quantum systems - of the 2 × 2 density matrices with real entries. The Gaussian curvatures of the corresponding Bures metrics are found to be constants ( 4 n ). In the second series of 2 n × 2 n density matrices analyzed, the singly -parameterized sets are formed - following an earlier study of Krattenthaler and Slater - by averaging with respect to a certain Gibbs distribution, the n -fold tensor products of the 2 × 2 density matrices with complex entries. For n = 100, we are able to compute the Bures distance between two arbitrary (not necessarily neighboring) density matrices in this particular series, making use of certain eigenvalue formulas of Krattenthaler and Slater, together with the knowledge that the 2 n × 2 n density matrices in the series commute.
Exponential attractors of optimal Lyapunov dimension for Navier-Stokes equations

In this paper we present a new construction of exponential attractors based on the control of Lyapunov exponents over a compact, invariant set. The fractal dimension estimate of the exponential attractor thus obtained is of the same order as the one for global attractors estimated through Lyapunov exponents. We discuss various applications to Navier-Stokes systems.
NUMERICAL MODELING OF THE 2009 IMPACT EVENT ON JUPITER

We have investigated the 2009 July impact event on Jupiter using the ZEUS-MP 2 three-dimensional hydrodynamics code. We studied the impact itself and the following plume development. Eight impactors were considered: 0.5 km and 1 km porous ({rho} = 1.760 g cm{sup -3}) and non-porous ({rho} = 2.700 g cm{sup -3}) basalt impactors, and 0.5 km and 1 km porous ({rho} = 0.600 g cm{sup -3}) and non-porous ({rho} = 0.917 g cm{sup -3}) ice impactors. The simulations consisted of these bolides colliding with Jupiter at an incident angle of {theta} = 69 Degree-Sign from the vertical and with an impact velocity of v = 61.4 km s{sup -1}. Our simulations show the development of relatively larger, faster plumes created after impacts involving 1 km diameter bodies. Comparing simulations of the 2009 event with simulations of the Shoemaker-Levy 9 (SL9) events reveals a difference in plume development, with the higher incident angle of the 2009 impact leading to a shallower terminal depth and a smaller and slower plume. We also studied the amount of dynamical chaos present in the simulations conducted at the 2009 incident angle. Compared to the chaos of the SL9 simulations, where {theta} Almost-Equal-To 45 Degree-Sign ,more » we find no significant difference in chaos at the higher 2009 incident angle.« less
Locally analytical prediction of the steady inviscid incompressible flow through an airfoil cascade

Abstract A mathematical model and locally analytical solution technique are developed to analyze the steady, inviscid, incompressible, flow through a two-dimensional turbomachinery cascade comprised of cambered, thick, airfoils. The cascade is analyzed by considering a single flow channel. The boundary conditions require a zero velocity normal to the airfoil surfaces, the Kutta condition to be satisfied, and the inlet and exit flow from the cascade to be periodic. The flow field velocity potential is separated into circulatory and noncirculatory components, each individually described by a Laplace equation. A body fitted computational grid is utilized which permits grid points to be specified along the entire computational boundary and results in a smoothly spaced, nonoverlapping grid. General analytic solutions to the Laplace equations in the transformed computational plane are determined by separation of variables. Locally analytical solutions are then developed by applying these solutions to individual grid elements, i.e. the integration and separation constants are determined from the boundary conditions in each grid element. The complete flow field solution is then obtained by assembling these locally analytical solutions. The validity of this locally analytical solution and the flow modelling are then demonstrated by correlation predictions with data from various cascade experiments.
Modeling and control of the in-situ thermoplastic composite tape-laying process

In thermoplastic tape-laying with in-situ consolidation, a laminated composite is constructed by the local application of heat and pressure. A moving head, applying heat and pressure, lays down and bonds a new layer to the previously bonded layers (substrate). The temperature at the interface between the top ply and the substrate is critical to achieving interlaminar bonding. Recent research on the in-situ thermoplastic composite tape-laying process has focused on modeling, numerical analysis and experimental analysis, but little research has considered the control of this process. In this work, a method is proposed for modeling and control of in-situ thermoplastic composite tape-laying. The key to the control algorithm is predicting the temperature at the interface between the top ply and the substrate. Based on a process model, a state feedback controller and a state estimator for temperature are designed for closed-loop control using the linear quadratic method. Two different approaches are used to develop the process model for real-time closed-loop control through temperature feedback. In the first approach, a low-order lumped parameter model is constructed from a finite difference scheme. The second approach constructs an empirical model through system identification. The structures of the two models are identical, but the parameters differ. The experimental results have shown that the developed estimator and controller can accurately estimate and control the bonding temperature using temperature feedback indicating that the proposed modeling and control methodology can produce a high quality thermoplastic composite laminate.
Atmospheric Circulation of Hot Jupiters: Three-dimensional circulation models of HD 209458b and HD 189733b with Simplified Forcing

We present global, three-dimensional numerical simulations of the atmospheric circulation on HD 209458b and HD 189733b and calculate the infrared spectra and light curves predicted by these simulations, which we compare with available observations. Radiative heating/cooling is parameterized with a simplified Newtonian relaxation scheme. Our simulations develop day-night temperature contrasts that vary strongly with pressure. At low pressure (<10 mbar), air flows from the substellar point toward the antistellar point, both along the equator and over the poles. At deeper levels, the flow develops an eastward equatorial jet with speeds of 3-4 km s−1, with weaker westward flows at high latitudes. This basic flow pattern is robust to variations in model resolution, gravity, radiative time constant, and initial temperature structure. Nightside spectra show deep absorption bands of H2O, CO, and/or CH4, whereas on the dayside these absorption bands flatten out or even flip into emission. This results from the strong effect of dynamics on the vertical temperature-pressure structure; the temperature decreases strongly with altitude on the nightside but becomes almost isothermal on the dayside. In Spitzer bandpasses, our predicted planet-to-star flux ratios vary by a factor of ~2-10 with orbital phase, depending on the wavelength and chemistry. For HD 189733b, where a detailed 8 μm light curve has been obtained, we correctly produce the observed phase offset of the flux maximum, but we do not explain the flux minimum and we overpredict the total flux variation. This discrepancy likely results from the simplifications inherent in the Newtonian relaxation scheme and provides motivation for incorporating realistic radiative transfer in future studies.
A square root formulation of the Kalman- Schmidt filter.

Kalman filter alternate form extended to include multiple simultaneous correlated measurements, testing with ballistic model and using square root formulation for trajectory determination
The Euler anomaly and scale factors in Liouville/Toda CFTs

The role played by the Euler anomaly in the dictionary relating sphere partition functions of four dimensional theories of class $ \mathcal{S} $ and two dimensional non rational CFTs is clarified. On the two dimensional side, this involves a careful treatment of scale factors in Liouville/Toda correlators. Using ideas from tinkertoy constructions for Gaiotto duality, a framework is proposed for evaluating these scale factors. The representation theory of Weyl groups plays a critical role in this framework.
A graphical approach for evaluating effective connectivity in neural systems

The identification of effective connectivity from time-series data such as electroencephalogram (EEG) or time-resolved function magnetic resonance imaging (fMRI) recordings is an important problem in brain imaging. One commonly used approach to inference effective connectivity is based on vector autoregressive models and the concept of Granger causality. However, this probabilistic concept of causality can lead to spurious causalities in the presence of latent variables. Recently, graphical models have been used to discuss problems of causal inference for multivariate data. In this paper, we extend these concepts to the case of time-series and present a graphical approach for discussing Granger-causal relationships among multiple time-series. In particular, we propose a new graphical representation that allows the characterization of spurious causality and, thus, can be used to investigate spurious causality. The method is demonstrated with concurrent EEG and fMRI recordings which are used to investigate the interrelations between the alpha rhythm in the EEG and blood oxygenation level dependent (BOLD) responses in the fMRI. The results confirm previous findings on the location of the source of the EEG alpha rhythm.
Heat Transfer and Pressure Drop Measurements in Constant and Converging Section Pin and Diamond Pedestal Arrays

High solidity pin and pedestal arrays are beneficial in reducing temperature gradients and distributing stress across double wall cooling channels such as trailing edge regions. In this study two high solidity (45%) cooling channel geometries were selected and tested in both constant channel height and converging channel configurations. One geometry consisted of a high solidity round pin fin array and the other geometry consisted of a rounded diamond pedestal array designed to minimize pressure drop. Heat transfer rates for both geometries were determined on a row by row basis for both the constant channel and converging channel configurations. Heat transfer and pressure drop measurements were acquired in a bench scale test rig. Reynolds numbers ranged from approximately 3000 to 60,000 for the constant channel arrays and 3500 to 100,000 for the converging arrays based on the characteristic dimension of the pin or pedestal and the local maximum average velocity across a row. The high solidity pin fin array had an axial spacing (X/D) of 1.043 and a cross channel spacing (Z/D) of 1.674. The high solidity diamond pedestal array had an axial spacing of 1.00 and a cross channel spacing of 1.93. The constant section pin fin array had a channel height to diameter of 0.95 while the constant section diamond pedestal array had a height to characteristic dimension of 0.96. The converging pin fin array had an inlet to exit convergence ratio of 2.87 over five heated rows while the converging pedestal array had an inlet to exit convergence ratio of 3.53 over seven heated rows. The constant channel height internal cooling schemes have shown that the high solidity pin fin and the rounded diamond pedestal arrays produce comparable heat transfer and array pressure drop. Both the converging channel arrays show a noticeable (5-7%) reduction in heat transfer compared with the constant height channels. Array pressure drop for the two converging geometries was found to be quite consistent.
Ion source design for industrial applications

ROAD-BEAM electron-bombardment ion sources are used for a wide range of industrial applications. There have been a number of reviews of the technology involved,1"5 in addition to the hundreds of papers upon which these reviews were based. Despite the availability of these publications, applications of this ion-source technology have resulted in frequent design problems and much cut-and-try development. The intent of this paper is to cover some of the more frequently used design techniques, together with examples of successful component design. There is no intent of completely covering ion-source technology. The intent is, instead, to give at least one specific design example for each component, to aid those that do not have an extensive background of ion-source design upon which to draw. The working gas Ar will be emphasized in performance calculations, although scaling relationships will be given for other gases. The presentation will.be divided into sections on the v gas feed, discharge chamber, ion optics, cathodes, magnetic design, and mechanical design. It should be mentioned that single-aperture ion sources have developed almost independently of multiaperture broadbeam sources. Although this paper has been directed primarily at broad-beam sources, much of what is presented is also applicable to single-aperture sources. Where appropriate, single-aperture technology is referenced.
Smooth Projective Toric Variety Representatives in Complex Cobordism

A general problem in complex cobordism theory is to find useful representatives for cobordism classes. One particularly convenient class of complex manifolds consists of smooth projective toric varieties. The bijective correspondence between these varieties and smooth polytopes allows us to examine which complex cobordism classes contain a smooth projective toric variety by studying the combinatorics of polytopes. These combinatorial properties determine obstructions to a complex cobordism class containing a smooth projective toric variety. However, the obstructions are only necessary conditions, and the actual distribution of smooth projective toric varieties in complex cobordism appears to be quite complicated. The techniques used here provide descriptions of smooth projective toric varieties in low-dimensional cobordism.
Statistical decision functions

The foundations of a general theory of statistical decision functions, including the classical non-sequential case as well as the sequential case, was discussed by the author in a previous publication [3]. Several assumptions made in [3] appear, however, to be unnecessarily restrictive (see conditions 1-7, pp. 297 in [3]). These assumptions, moreover, are not always fulfilled for statistical problems in their conventional form. In this paper the main results of [3], as well as several new results, are obtained from a considerably weaker set of conditions which are fulfilled for most of the statistical problems treated in the literature. It seemed necessary to abandon most of the methods of proofs used in [3] (particularly those in section 4 of [3]) and to develop the theory from the beginning. To make the present paper self-contained, the basic definitions already given in [3] are briefly restated in section 2.1.
Late proterozoic transpression on the Nabitah fault system―implications for the assembly of the Arabian Shield

Abstract The longest proposed suture zone in Saudi Arabia, the Nabitah suture, can be traced as a string of ophiolite complexes for 1200 km along the north-south axis of the Arabian Shield. Results of a field study in the north-central shield between 23° and 26°N indicate that the Nabitah suture is indeed a major crustal discontinuity across which hundreds of kilometers of displacement may have occurred on north-south trending, subvertical faults of the Nabitah fault system. Although not a unique solution, many structures within and near these faults can be reconciled with transpression, i.e., convergent strike-slip, and syntectonic emplacement of calc-alkaline plutonic rocks. Transcurrent motion on the Nabitah fault system appears to have began prior to 710 Ma, was active circa 680 Ma, and terminated prior to significant left-lateral, strike slip on the Najd fault system, which began sometime after 650 Ma. Northwest-directed subduction in the eastern shield could have produced the observed association of calc-alkaline magmatism and left-lateral transpressive strike slip, and is consistent with interpretation of the Abt schist and sedimentary rocks of the Murdama group as relics of the associated accretionary wedge and fore-arc basin.
Relationship between bat mass properties and bat velocity

The relationship between bat mass properties (mass and moment of inertia) and bat velocity (linear and angular) was investigated for baseball and softball. Seventeen male collegiate baseball players and 17 female collegiate softball players were tested swinging aluminium alloy bats engineered with various mass and moments of inertia. Motions of reflective markers attached to the pitched ball, bat handle and bat barrel were tracked with a high-speed three-dimensional motion analysis system. Linear velocity of the bat's `sweet spot' (defined here as 15 cm from the end of the bat barrel towards the handle) and angular velocity of the bat were calculated from the motion data. Analysis of variance revealed significant differences (P < 0.05) in bat linear velocity among the baseball bats tested (24.7–26.8 m · s−1) and among softball bats tested (19.4–22.2 m · s−1). Variations in bat angular velocity were non-significant for both the baseball bats (2080–2280 ° s−1) and softball bats (1740–1890 ° s−1). Regression analysis showed a linear correlation between bat linear velocity and bat moment of inertia, both for baseball and softball. Results from this study suggest that if limitations in bat velocity are desired, bat moment of inertia – not bat mass – should be regulated.
Thermal–mechanical coupled analysis of a brake disk rotor

The main purpose of this study is to analyze the thermomechanical behavior of the dry contact between the brake disk and pads during the braking phase. The simulation strategy is based on computer code ANSYS11. The modeling of transient temperature in the disk is actually used to identify the factor of geometric design of the disk to install the ventilation system in vehicles The thermal–structural analysis is then used with coupling to determine the deformation and the Von Mises stress established in the disk, the contact pressure distribution in pads. The results are satisfactory when compared to those of the specialized literature.