cssi/SciSciGPT-SciSciNet huggingface dataset:
Mantle P-wave velocity structure beneath the Hawaiian hotspot

Abstract Three-dimensional images of P -wave velocity structure beneath the Hawaiian Islands, obtained from a network of seafloor and land seismometers, show an upper-mantle low-velocity anomaly that is elongated in the direction of the island chain and surrounded by a high-velocity anomaly in the shallow upper mantle that is parabolic in map view. Low velocities continue downward to the mantle transition zone between 410 and 660 km depth and extend into the topmost lower mantle, although the resolution of lower mantle structure from this data set is limited. Comparisons of inversions with separate data sets at different frequencies suggest that contamination by water reverberations is not markedly biasing the P -wave imaging of mantle structure. Many aspects of the P -wave images are consistent with independent tomographic images of S -wave velocity in the region, but there are some differences in upper mantle structure between P -wave and S -wave velocities. Inversions without station terms show a southwestward shift in the location of lowest P -wave velocities in the uppermost mantle relative to the pattern for shear waves, and inversions with station terms show differences between P -wave and S -wave velocity heterogeneity in the shallow upper mantle beneath and immediately east of the island of Hawaii. Nonetheless, the combined data sets are in general agreement with the hypothesis that the Hawaiian hotspot is the result of an upwelling, high-temperature plume. The broad upper-mantle low-velocity region beneath the Hawaiian Islands may reflect the diverging “pancake” at the top of the upwelling zone; the surrounding region of high velocities could represent a downwelling curtain; and the low-velocity anomalies southeast of Hawaii in the transition zone and topmost lower mantle are consistent with predictions of plume tilt.
The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies

We review a sample of the early literature in which the reality of the expansion is discussed. Hubble's reluctance, even as late as 1953, to accept the expansion as real is explained as due to his use of equations for distances and absolute magnitudes of redshifted galaxies that do not conform to the modern Mattig equations of the standard model. The Tolman surface brightness test, once the only known test for the reality of the expansion, is contrasted with three other modern tests. These are (1) the time dilation in Type Ia supernovae light curves, (2) the temperature of the relic radiation as a function of redshift, and (3) the surface brightness normalization of the Planckian shape of the relic radiation. We search for the Tolman surface brightness depression with redshift using the Hubble Space Telescope (HST) data from Paper III for 34 early-type galaxies from the three clusters Cl 1324+3011 (z = 0.76), Cl 1604+4304 (z = 0.90), and Cl 1604+4321 (z = 0.92). Depressions of the surface brightness relative to the zero-redshift fiducial lines in the mean surface brightness–logarithm of the linear radius diagrams of Paper I are found for all three clusters. Expressed as the exponent, n, in 2.5 log (1 + z)n mag, the value of n averaged over Petrosian radii of η = 1.7 and η = 2.0 for all three clusters is n = 2.59 ± 0.17 in the R band and 3.37 ± 0.13 in the I band for a q0 = 1/2 model. The sensitivity of the result to the assumed value of q0 is shown to be less than 23% between q = 0 and +1. The conclusion is that the exponent on (1 + z) varies from 2.28 to 2.81 (± 0.17) in the R band and 3.06 to 3.55 (± 0.13) in the I band, depending on the value of q0. For a true Tolman signal with n = 4, the luminosity evolution in the look-back time, expressed as the exponent in 2.5 log (1 + z)4-n mag, must then be between 1.72 to 1.19 (± 0.17) in the R band and 0.94 to 0.45 (± 0.13) in the I band. We show that this is precisely the range expected from the evolutionary models of Bruzual and Charlot and other measurements of the luminosity evolution of early-type galaxies. We conclude that the Tolman surface brightness test is consistent with the reality of the expansion to within the combined errors of the observed SB depression and the theoretical correction for luminosity evolution. We have also used the high-redshift HST data to test the "tired light" speculation for a nonexpansion model for the redshift. The HST data rule out the tired light model at a significance level of better than 10 σ.
ON THE FUNCTIONAL INTEGRAL THEORY OF SYSTEMS WITH KINEMATICAL INTERACTION

Abstract We propose a systematic way to investigate the low-temperature thermodynamic properties of quantum spin systems subject to the restriction that only a finite number of bosons may occupy a single lattice site. Such a kinematical interaction results in the appearance of a temperature dependent chemical potential. Its low-temperature asymptotics is calculated self-consistently using the functional integration technique.
Plasma irregularities in the comet's tail

Scintillation theory is invoked to explain fluctuations in radio intensity observed during occultation of the extragalactic radio source PKS 2025-15 by the plasma tail of comet 1973 XII on Jan. 5, 1975. Plasma irregularities and turbulence in the tail of the comet (Kohoutek 1973f) are fitted to a Gaussian spectrum and to a Kolmogorov power-law spectrum in analyzing the scintillation data. The rms fluctuation of electron density in the cometary tail is reported at 80 electrons per cu mm, the inner scale of the fluctuation at 800 km, and the largest scale of fluctuation at possibly 400,000 km. A hump in the comet power-law spectrum is noted. Use of the power spectrum of electron density fluctuations to predict the power spectrum of magnetic field fluctuations for irregularities associated with hydromagnetic turbulence is recommended.
Revisiting top–bottom-tau Yukawa unification in supersymmetric grand unified theories

Abstract Third family Yukawa unification, as suggested by minimal SO(10) unification, is revisited in light of recent experimental measurements and theoretical progress. We characterize unification in a semi-model-independent fashion, and conclude that finite b quark mass corrections from superpartners must be non-zero, but much smaller than naively would be expected. We show that a solution that does not require cancellations of dangerously large tanβ effects in observables implies that scalar superpartner masses should be substantially heavier than the Z scale, and perhaps inaccessible to all currently approved colliders. On the other hand, gauginos must be significantly lighter than the scalars. We demonstrate that a spectrum of anomaly-mediated gaugino masses and heavy scalars works well as a theory compatible with third family Yukawa unification and dark matter observations.
An octree multigrid method for quasi-static Maxwell's equations with highly discontinuous coefficients

In this paper we develop an OcTree discretization for Maxwell's equations in the quasi-static regime. We then use this discretization in order to develop a multigrid method for Maxwell's equations with highly discontinuous coefficients. We test our algorithms and compare it to other multilevel algorithms.
Virtual fundamental classes via dg-manifolds

We construct virtual fundamental classes for dg‐manifolds whose tangent sheaves have cohomology only in degrees 0 and 1. This condition is analogous to the existence of a perfect obstruction theory in the approach of Behrend and Fantechi [3] or Li and Tian [11]. Our class is initially defined in K ‐theory as the class of the structure sheaf of the dg‐manifold. We compare our construction with that of [3] as well as with the original proposal of Kontsevich. We prove a Riemann‐Roch type result for dg‐ manifolds which involves integration over the virtual class. We prove a localization theorem for our virtual classes. We also associate to any dg‐manifold of our type a cobordism class of almost complex (smooth) manifolds. This supports the intuition that working with dg‐manifolds is the correct algebro-geometric replacement of the analytic technique of “deforming to transversal intersection”. 14F05; 14A20
Witten's nonabelian localization for noncompact Hamiltonian spaces

Abstract For a finite-dimensional (but possibly noncompact) symplectic manifold with a compact group acting with a proper moment map, we show that the square of the moment map is an equivariantly perfect Morse function in the sense of Kirwan, show that certain integrals of equivariant cohomology classes localize as a sum of contributions from these compact critical sets, and bound the contribution from each critical set. In the case (1) that the contribution from higher critical sets grows slowly enough that the overall integral converges rapidly and (2) that 0 is a regular value of the moment map, we recover Witten's result [E. Witten, Two dimensional gauge theories revisited, J. Geom. Phys. 9 (1992) 303–368; http://xxx.lanl.gov/abs/hep-th/9204083 ] identifying the polynomial part of these integrals as the ordinary integral of the image of the class under the Kirwan map to the symplectic quotient.
Computational Studies of the Gramicidin Channel

Ion channels are highly specific membrane-spanning protein structures which serve to facilitate the passage of selected ions across the lipid barrier. In the past decade, molecular dynamics simulations based on atomic models and realistic microscopic interactions with explicit solvent and membrane lipids have been used to gain insight into the function of these complex systems. These calculations have considerably expanded our view of ion permeation at the microscopic level. This Account will mainly focus on computational studies of the gramicidin A channel, one of the simplest and best characterized molecular pore.
Modified Rayleigh Conjecture Method for Multidimensional Obstacle Scattering Problems

ABSTRACT The Rayleigh conjecture on the representation of the scattered field in the exterior of an obstacle D is widely used in applications. However, this conjecture is false for some obstacles. A.G.R. introduced the modified Rayleigh conjecture (MRC), and in this paper we present successful numerical algorithms based on the MRC for various 2D and 3D obstacle scattering problems. The 3D obstacles include a cube and an ellipsoid. The MRC method is easy to implement for both simple and complex geometries. It is shown to be a viable alternative for other obstacle scattering methods.
Asymmetric Pt(II)-catalyzed ene reactions: counterion-dependent additive and diphosphine electronic effects.

Catalysis of the glyoxylate−ene reaction by dicationic P2Pt(II) complexes is subject to anion-dependent additive effects. For [((S)-MeOBiphep)Pt](OTf)2 catalysts, acidic phenols such as 3-CF3-C6H3OH or C6F5OH provide substantial rate increases but do not affect the more active SbF6-based catalysts. Enantioselectivity and reactivity also increased with diphosphine basicity, with 4-t-Bu-substituted MeOBiphep ligands yielding the highest enantioselectivities.
Robust and efficient digital audio watermarking using audio content analysis

Digital audio watermarking embeds inaudible information into digital audio data for the purposes of copyright protection, ownership verification, covert communication, and/or auxiliary data carrying. In this paper, we first describe the desirable characteristics of digital audio watermarks. Previous work on audio watermarking, which has primarily focused on the inaudibility of the embedded watermark and its robustness against attacks such as compression and noise, is then reviewed. In this research, special attention is paid to the synchronization attack caused by casual audio editing or malicious random cropping, which is a low-cost yet effective attack to watermarking algorithms developed before. A digital audio watermarking scheme of low complexity is proposed in this research as an effective way to deter users from misusing or illegally distributing audio data. The proposed scheme is based on audio content analysis using the wavelet filterbank while the watermark is embedded in the Fourier transform domain. A blind watermark detection technique is developed to identify the embedded watermark under various types of attacks.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
DIFFUSE TIDAL STRUCTURES IN THE HALOS OF VIRGO ELLIPTICALS

We use deep V-band surface photometry of five of the brightest elliptical galaxies in the Virgo Cluster to search for diffuse tidal streams, shells, and plumes in their outer halos (r>50 kpc). We fit and subtract elliptical isophotal models from the galaxy images to reveal a variety of substructure, with surface brightnesses in the range {mu} {sub V} = 26-29 mag arcsec{sup -2}. M49 possesses an extended, interleaved shell system reminiscent of the radial accretion of a satellite companion, while M89's complex system of shells and plumes suggests a more complicated accretion history involving either multiple events or a major merger. M87 has a set of long streamers as might be expected from stripping of low luminosity dwarfs on radial orbits in Virgo. M86 also displays a number of small streams indicative of stripping of dwarf companions, but these comprise much less luminosity than those of M87. Only M84 lacks significant tidal features. We quantify the photometric properties of these structures, and discuss their origins in the context of each galaxy's environment and kinematics within the Virgo Cluster.
Diffusion Approximation for Disordered Photonic Crystals

We develop a theoretical framework for description of diffusive radiative transport in disordered photonic crystals. We define an inhomogeneous equilibrium distribution of light intensity inside photonic crystals and derive the static limit of diffusion equation.
Habitable zones in the universe

Habitability varies dramatically with location and time in the universe. This was recognized centuries ago, but it was only in the last few decades that astronomers began to systematize the study of habitability. The introduction of the concept of the habitable zone was key to progress in this area. The habitable zone concept was first applied to the space around a star, now called the Circumstellar Habitable Zone. Recently, other, vastly broader, habitable zones have been proposed. We review the historical development of the concept of habitable zones and the present state of the research. We also suggest ways to make progress on each of the habitable zones and to unify them into a single concept encompassing the entire universe.
Formal representation of the SS-DB benchmark and experimental evaluation in EXTASCID

Evaluating the performance of scientific data processing systems is a difficult task considering the plethora of application-specific solutions available in this landscape and the lack of a generally-accepted benchmark. The dual structure of scientific data coupled with the complex nature of processing complicate the evaluation procedure further. SS-DB is the first attempt to define a general benchmark for complex scientific processing over raw and derived data. It fails to draw sufficient attention though because of the ambiguous plain language specification and the extraordinary SciDB results. In this paper, we remedy the shortcomings of the original SS-DB specification by providing a formal representation in terms of ArrayQL algebra operators and ArrayQL/SciQL constructs. These are the first formal representations of the SS-DB benchmark. Starting from the formal representation, we give a reference implementation and present benchmark results in EXTASCID, a novel system for scientific data processing. EXTASCID is complete in providing native support both for array and relational data and extensible in executing any user code inside the system by the means of a configurable metaoperator. These features result in significant improvement over SciDB at data loading, extracting derived data, and operations over derived data.
Revisiting the Relation between the Default Risk of Debt and the Earnings Response Coefficient

Theory suggests that earnings response coefficients (ERCs) are positively associated with expected earnings growth and negatively associated with equity risk. Dhaliwal and Reynolds (1994) (DR) hypothesize that equity beta fails to capture a default risk component of equity risk and demonstrate that ERCs are negatively associated with two measures of default risk—bond ratings and debt/equity ratios—in a regression model that contains equity beta. Bond ratings and debt/equity ratios are associated with expected earnings growth. This paper examines how the association between ERCs and default risk is impacted by the inclusion of expected earnings growth in the model. The relation between ERCs and bond ratings is not significant, while the association between ERCs and debt/equity ratios is weakened but is still significant. These findings suggest part of the reason for the negative association between ERCs and default risk in DR is that their default risk proxies also reflect expected earnings growth. In fact...
Maximum-likelihood blind equalization

A new approach to blind equalization is investigated in which the receiver performs joint data and channel estimation in an iterative manner. Instead of estimating the channel inverse, the receiver computes the maximum-likelihood estimate of the channel itself. The iterative algorithm that is developed involves maximum-likelihood sequence estimation (Viterbi decoding) for the data estimation part, and least-squares estimation for the channel estimation part. A suboptimal algorithm is also proposed that uses a reduced-state trellis instead of the Viterbi algorithm. Simulation results show that the performance obtained by these algorithms is comparable to that of a receiver operating with complete knowledge of the channel.
Nonparametric estimation of triangular simultaneous equations models

This paper presents a simple two-step nonparametric estimator for a triangular simultaneous equation model. Our approach employs series approximations that exploit the additive structure of the model. The first step comprises the nonparametric estimation of the reduced form and the corresponding residuals. The second step is the estimation of the primary equation via nonparametric regression with the reduced form residuals included as a regressor. We derive consistency and asymptotic normality results for our estimator, including optimal convergence rates. Finally we present an empirical example, based on the relationship between the hourly wage rate and annual hours worked, which illustrates the utility of our approach.
Definability with bounded number of bound variables

Abstract A theory satisfies the k-variable property if every first-order formula is equivalent to a formula with at most k bound variables (possibly reused). Gabbay has shown that a model of temporal logic satisfies the k -variable property for some k if and only if there exists a finite basis for the temporal connectives over that model. We give a model-theoretic method for establishing the k -variable property, involving a restricted Ehrenfeucht-Fraisse game in which each player has only k pebbles. We use the method to unify and simplify results in the literature for linear orders. We also establish new k -variable properties for various theories of bounded-degree trees, and in each case obtain tight upper and lower bounds on k . This gives the first finite basis theorems for branching-time models of temporal logic.
Processing and Electrical Properties of Alkaline Earth‐Doped Lanthanum Gallate

Oxides exhibiting substantial oxygen ion conductivity are utilized in a number of high-temperature applications, including solid oxide fuel cells, oxygen separation membranes, membrane reactors, and oxygen sensors. Alkaline earth-doped lanthanum gallate powders were prepared by glycine/nitrate combustion synthesis. Compacts of powders synthesized under fuel-rich conditions were sintered to densities greater than 97% of theoretical. Appropriate doping with Sr or Ba on the A-site of the perovskite structure, and Mg on the B-site, resulted in oxygen ion conductivity higher than that of yttria-stabilized zirconia (YSZ), and high ionic transference numbers. Doping with Ca and Mg resulted in lower conductivity than YSZ. Thermal expansion coefficients of the doped gallates were higher than that of YSZ.
Trapping of gun‐injected plasma by a tokamak

It has been seen that a plasma produced by a Marshall gun can be injected into and trapped by a tokamak plasma. This trapping of a gun‐injected plasma is explained in terms of a depolarization current mechanism. A model is developed that describes the slowing of a plasma beam crossing into the magnetic field of a tokamak. The slowing down time is shown to go as τs∝T3/2eL2/nbα20, where nb and Te are the density and temperature of the plasma beam and α0/L is the pitch of the field lines per unit length in the direction in which the beam is traveling. Experimental tests of this model are consistent with the scaling predictions.
The Expected Rate of Gamma-Ray Burst Afterglows in Supernova Searches

We predict the rate at which gamma-ray burst (GRB) afterglows should be detected in supernova (SN) searches as a function of limiting flux. Although GRB afterglows are rarer than supernovae (SNs), they are detectable at greater distances because of their higher intrinsic luminosity. Assuming that GRBs trace the cosmic star formation history and that every GRB gives rise to a bright afterglow, we find that the average detection rate of SNs and afterglows should be comparable at limiting magnitudes brighter than K = 18. The actual rate of afterglows is expected to be somewhat lower since only a fraction of all gamma-ray-selected GRBs were observed to have associated afterglows. Hence, current and future SN searches can place strong constraints on the afterglow appearance fraction of GRB sources.
Dynamic Analysis of Flexible Supercavitating Vehicles Using Modal-Based Elements

This article presents a numerical model for the simulation of the flight mechanics behavior of flexible supercavitating vehicles. Supercavitating vehicles exploit supercavitation as a means to reduce drag and increase underwater speed. In the proposed formulation, the vehicle's rigid body motion is described by six degrees of freedom, which define pitch, yaw, and roll motion and the displacement of the center of gravity with respect to an inertial reference system. The developed numerical model predicts the dynamic response of the vehicles resulting from perturbation of the control surfaces and assigned maneuvers. The results highlight the potential instability of the vehicles' behavior and its sensitivity to the considered control maneuvers. The analysis is motivated by the need of accurately modeling the structural characteristics of supercavitating vehicles to estimate vibrations in the structure and to envision and design systems that improve their guidance and control efficiency.
Learning through the international joint venture: lessons from the experience of China's automotive sector

This study explores why international joint ventures (IJVs) based on the global South may meet with only partial success in nurturing local technological capability. The experience of China’s passenger-vehicle sector demonstrates that in the existence of a substantial technological capability gap between alliance partners, the IJV arrangement is likely to create a “passive” learning mode, and learners using this IJV arrangement may be able to strengthen their production capability but leaving their project execution and innovation capabilities largely undeveloped.
Bingham procrustean alignment for object detection in clutter

A new system for object detection in cluttered RGB-D images is presented. Our main contribution is a new method called Bingham Procrustean Alignment (BPA) to align models with the scene. BPA uses point correspondences between oriented features to derive a probability distribution over possible model poses. The orientation component of this distribution, conditioned on the position, is shown to be a Bingham distribution. This result also applies to the classic problem of least-squares alignment of point sets, when point features are orientation-less, and gives a principled, probabilistic way to measure pose uncertainty in the rigid alignment problem. Our detection system leverages BPA to achieve more reliable object detections in clutter.
Strategies for managing EUC on the Web

Beginning in the early 1980s, end-user computing (EUC) began to permeate organizations following the advent of the personal computer and a host of applications directed at the non-IS professional. Along with EUC came a whole new set of organizational opportunities and risks. Ten years later the World Wide Web has opened the door to a yet more powerful set of EUC applications capable of reaching well beyond the boundaries of the organization. Indeed, Web technology permits end users to design applications that are immediately accessible by unlimited numbers of people from anywhere in the world. As a result, EUC using Web technology has introduced a whole new set of opportunities and risks for organizations. The purpose of this research is to examine what strategies organizations are using in their attempt to maximize the benefits of the Web for end users while mitigating the inherent risks. To this end, individuals from twelve major organizations were surveyed via the Web. The results indicate that while organizations seem to be doing an adequate job of establishing roles and standards, mechanisms for resource allocation, development management, and maintenance appear to be lacking. In fact, most firms seem to be relying on a monopolist control strategy at this point in time. While such a strategy may be the best approach given tile relative infancy of Web technology, it could prove to be an unstable strategy in the long run given the reach, range and flexibility of access that Web technology provides. Organizations are encouraged to take a proactive, formal posture toward EUC development on the Web.
Morphological stability of alloy thin films

We examine the linear stability of a planar, alloy thin film, growing by a deposition flux from the vapor. The stability of the film surface is influenced by stresses generated by both compositional inhomogeneity, via a composition dependent lattice parameter, and lattice mismatch between the film and substrate. The stress generated by the compositional inhomogeneities, which accompany nonplanar interfacial morphologies, can be either stabilizing or destabilizing. Under certain conditions, a growing planar film under tensile misfit-strain can be stable, whereas a growing film under the same magnitude of compressive strain can be unstable. These compositionally generated stresses can also lead to traveling or standing surface waves and unstable planar surfaces in lattice matched films. All of these instabilities can develop via the deposition process itself; the wave number dependence of the instability is different, however, from that in the pure surface diffusion limit. We also compare our results with numerous experimental observations. \textcopyright{} 1996 The American Physical Society.
Mars ozone: Mariner 9 revisited

The efficacy of the UV reflectance spectroscopy technique used by Mariner 9 to remotely measure ozone abundance at Mars is discussed. Due to temporal and spatial variability in cloud and dust amount, previously inferred ozone abundances could be underestimated by a factor of 3. Until the large uncertainty in cloud and dust scattering properties and opacities can be reduced, the ozone abundance inferred by the reflectance spectroscopy technique will always have significant uncertainty.
Vacancy migration enthalpy in tungsten at high temperatures

Abstract The curvature found in the Arrhenius plot for tungsten self-diffusion has been commonly interpreted in terms of simultaneous diffusion by two different defect processes. An alternative interpretation has been in terms of the temperature dependence of the migration enthalpy H m 1V and/or the formation enthalpy H f 1V for single vacancies. In order to study the magnitude of the temperature dependence of the migration enthalpy H m, the present experiments were done to study the annealing of a supersaturation of vacancies at high temperatures in tungsten. The annealing of vacancies was monitored by interrupting quenches from 2900 K at well-defined anneal temperatures T a for a series of different time periods, followed by a quench to 300 K. The quenched-in resistivity Δρq was subsequently measured at 4 K. The decay of Δρq was observed for approximately ten delay times at each anneal temperature in order to define a characteristic decay time τ1/2. Analysis of the decay curves showed that at all the an...
Higher-order Nielsen numbers

Suppose , are manifolds, are maps. The well-known coincidence problem studies the coincidence set . The number is called the codimension of the problem. More general is the preimage problem. For a map and a submanifold of , it studies the preimage set , and the codimension is . In case of codimension , the classical Nielsen number is a lower estimate of the number of points in changing under homotopies of , and for an arbitrary codimension, of the number of components of . We extend this theory to take into account other topological characteristics of . The goal is to find a "lower estimate" of the bordism group of . The answer is the Nielsen group defined as follows. In the classical definition, the Nielsen equivalence of points of based on paths is replaced with an equivalence of singular submanifolds of based on bordisms. We let , then the Nielsen group of order is the part of preserved under homotopies of . The Nielsen number of order is the rank of this group (then ). These numbers are new obstructions to removability of coincidences and preimages. Some examples and computations are provided.
The main injector particle production experiment (MIPP) at Fermilab

Abstract We describe the physics capabilities and status of the main injector particle production (MIPP) experiment which is scheduled to enter its physics data taking period during December 2004–July 2005. We show some of the results obtained from the engineering run that concluded in August 2004 and point out the unique features of MIPP that make it an ideal apparatus to study non-perturbative QCD properties.
Ordering of random walks: the leader and the laggard

We investigate two complementary problems related to maintaining the relative positions of N random walks on the line: (i) the leader problem, that is, the probability N(t) that the leftmost particle remains the leftmost as a function of time and (ii) the laggard problem, the probability N(t) that the rightmost particle never becomes the leftmost. We map these ordering problems onto an equivalent (N ? 1)-dimensional electrostatic problem. From this construction we obtain a very accurate estimate for N(t) for N = 4, the first case that is not exactly solvable: 4(t) t??4, with ?4 = 0.91342(8). The probability of being the laggard also decays algebraically, N(t) t??N; we derive ?2 = 1/2, ?3 = 3/8, and argue that ?N ? N?1 ln N as N ? ?.
An approximation algorithm for a bottleneck traveling salesman problem

Consider a truck running along a road. It picks up a load L"i at point @b"i and delivers it at @a"i, carrying at most one load at a time. The speed on the various parts of the road in one direction is given by f(x) and that in the other direction is given by g(x). Minimizing the total time spent to deliver loads L"1,...,L"n is equivalent to solving the traveling salesman problem (TSP) where the cities correspond to the loads L"i with coordinates (@a"i,@b"i) and the distance from L"i to L"j is given by @!"@a"""i^@b^"^jf(x)dx if @b"j>[email protected]"i and by @!"@b"""j^@a^"^ig(x)dx if @b"j =f(x)g(x)>[email protected]@?x. Note that when f(x)=g(x), the approximation ratio is 3.
Design of a high level language machine

This paper presents mechanisms to be realized on a basic, capability - based architecture, to support the execution of PL/1, COBOL and FORTRAN languages, while ensuring error confinement and facilitating error detection and categorization. The concept of domain is used in order to support various linking strategies. The addressing space of a task is structured according to three characteristics of its components: scope, lifetime and access rights. The semantics to be associated to data structures and data types are explored and a 3-address instruction set is proposed.
Plasma source ion implantation of metal ions: Synchronization of cathodic-arc plasma production and target bias pulses

Abstract An erbium cathodic-arc has been installed on a plasma source ion implantation (PSII) experiment to allow the implantation of erbium metal and the growth of adherent erbia (erbium oxide) films on a variety of substrates. The operation of the PSII puiser and the cathodic-arc are synchronized to achieve pure implantation, rather than the hybrid implantation/deposition being investigated in other laboratories. The relative phase of the 20 μs PSII and the cathodic-arc pulses can be adjusted to tailor the energy distribution of the implanted ions and suppress the initial high-current drain on the pulse modulator. We present experimental data on this effect and make a comparison with the results from particle-in-cell simulations.
Inconsistent inheritance of telomere length (TL): is offspring TL more strongly correlated with maternal or paternal TL?

Inconsistent inheritance of telomere length (TL): is offspring TL more strongly correlated with maternal or paternal TL?
Wavelet transforms of cluttered images and their application to computing the probability of detection

Wavelet transforms are currently being used for a number of applications such as cue feature and noise extraction from images and acoustic signals. This work describes and applies an algorithm that uses wavelets for finding the clutter in infrared (IR) and visual images. Once the clutter is found, the probability of detection (Pd) is calculated. Tidhar’s and Rotman’s probability of edge metric (POE) is extended to encompass the wavelet methodology for multiscale clutter metrics in IR images.
Rapid Decarboxylative Allylation of Nitroalkanes

Allyl nitroacetates undergo decarboxylative allylation to provide tertiary nitroalkanes in high yield. Moreover, the transformations are complete within several minutes under ambient conditions. High yields result because O-allylation of the intermediate nitronates, which is typically problematic, is reversible under conditions of the decarboxylative allylation process. Lastly, the preparation of substrate allyl nitroacetates by tandem Knoevenagel/Diels−Alder sequences allows the facile synthesis of relatively complex substrates that undergo diastereoselective decarboxylative allylation.
Realizing the increased potential of an open system high definition digital projector design

Modern video projectors are becoming more compact and capable. Various display technologies are very competitive and are delivering higher performance and more compact projectors to market at an ever quickening pace. However the end users are often left with the daunting task of integrating the 'off the self projectors' into a previously existing system. As the projectors become more digitally enhanced, there will be a series of designs, and the digital projector technology matures. The design solutions will be restricted by the state of the art at the time of manufacturing. In order to allow the most growth and performance for a given price, many design decisions will be made and revisited over a period of years or decades. A modular open digital system design concept is indeed a major challenge of the future high definition digital displays for al applications.
When do the USDA forecasters make mistakes

This study analysed forecasts for all US corn, soya bean and wheat categories published within the World Agricultural Supply and Demand Estimates (WASDE ) reports over the 1987/88 through 2009/10 marketing years in an attempt to identify patterns and better understand when the USDA forecasters make mistakes. Two general sources of errors were investigated: behavioural and macroeconomic factors. The first objective was to examine how these factors affect the size of the forecast error and the second concentrated on the direction of the error due to these effects. Our findings suggest that the largest increase in the size of USDA forecast errors was associated with structural changes in commodity markets that took place in the mid-2000s. Corn, soya bean and wheat forecast errors also grew during the periods of economic growth and with changes in exchange rates, while inflation and changes in oil price had a much smaller impact. With respect to behavioural sources, we identified patterns consistent with leni...
Multi-resonant silver nano-disk patterned thin film hydrogenated amorphous silicon solar cells for Staebler-Wronski effect compensation

We study polarization independent improved light trapping in commercial thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic cells using a three-dimensional silver array of multi-resonant nano-disk structures embedded in a silicon nitride anti-reflection coating to enhance optical absorption in the intrinsic layer (i-a-Si:H) for the visible spectrum for any polarization angle. Predicted total optical enhancement (OE) in absorption in the i-a-Si:H for AM-1.5 solar spectrum is 18.51% as compared to the reference, and producing a 19.65% improvement in short-circuit current density (JSC) over 11.7 mA/cm2 for a reference cell. The JSC in the nano-disk patterned solar cell (NDPSC) was found to be higher than the commercial reference structure for any incident angle. The NDPSC has a multi-resonant optical response for the visible spectrum and the associated mechanism for OE in i-a-Si:H layer is excitation of Fabry-Perot resonance facilitated by surface plasmon resonances. The detrimental Staebler-Wronski effect in a-Si:H solar cell can be minimized by the additional OE in the NDPSC and self-annealing of defect states by additional heat generation, thus likely improving the overall stabilized characteristics of a-Si:H solar cells.
Shape optimization of peristaltic pumping

Transport is a fundamental aspect of biology and peristaltic pumping is a fundamental mechanism to accomplish this; it is also important to many industrial processes. We present a variational method for optimizing the wave shape of a peristaltic pump. Specifically, we optimize the wave profile of a two dimensional channel containing a Navier-Stokes fluid with no assumption on the wave profile other than it is a traveling wave (e.g. we do not assume it is the graph of a function). Hence, this is an infinite-dimensional optimization problem. The optimization criteria consists of minimizing the input fluid power (due to the peristaltic wave) subject to constraints on the average flux of fluid and area of the channel. Sensitivities of the cost and constraints are computed variationally via shape differential calculus and we use a sequential quadratic programming (SQP) method to find a solution of the first order KKT conditions. We also use a merit-function based line search in order to balance between decreasing the cost and keeping the constraints satisfied when updating the channel shape. Our numerical implementation uses a finite element method for computing a solution of the Navier-Stokes equations, adjoint equations, as well as for the SQP method when computing perturbations of the channel shape. The walls of the channel are deformed by an explicit front-tracking approach. In computing functional sensitivities with respect to shape, we use L^2-type projections for computing boundary stresses and for geometric quantities such as the tangent field on the channel walls and the curvature; we show error estimates for the boundary stress and tangent field approximations. As a result, we find optimized shapes that are not obvious and have not been previously reported in the peristaltic pumping literature. Specifically, we see highly asymmetric wave shapes that are far from being sine waves. Many examples are shown for a range of fluxes and Reynolds numbers up to Re=500 which illustrate the capabilities of our method.
Silent Acquiescence on the Supreme Court

The norm of silent acquiescence on the Supreme Court was thought to have been eviscerated in the twentieth century by certain institutional reforms and the rise of dissenting opinions. Given that silent acquiescence is difficult to observe, however, the extent to which this norm persists on the modern Court remains unclear. To overcome this observational difficulty, I analyze private memoranda exchanged by justices who served during the Burger Court. The empirical results suggest that silent acquiescence is a rare but regular occurrence on the modern Court, and is more likely to occur in comparatively unimportant cases. Notwithstanding institutional and personnel changes that limited silent acquiescence and precipitated an increase in dissenting opinions, it appears that the practice of go-along voting continued throughout the Burger Court. The results have implications for our understanding of separate opinion writing, judicial decision-making, and judicial legitimacy.
Underwriter Lock‐up Releases, Initial Public Offerings and After‐market Performance

The lock-up agreement between an underwriter and an issuing firm's principals prohibits sale of securities for a period of time following the offering date. Investment banks must support the stock following an offering. The lock-up assures investors that the restricted shares will not enter the market, at least for a period of time. Negative abnormal returns prior to the lock-up release show that unrestricted investors liquidate positions prior to the scheduled lock-up release. Negative abnormal returns are more robust for firms that are not influenced by SEC Rule 144 than for firms that are.
Random fields and ordering in antiferromagnetic insulators

Abstract Neutron scattering measurements of the effect on the long-range order and phase transitions of random magnetic fields are reviewed. The results at low temperatures in Rb 2 Co x Mg 1− x F 4 and Co x Zn 1− x F 2 show that the long-range order is not established when samples are cooled in a magnetic field, but they form a state with unusually long magnetic correlations. In Mn x Zn 1− x F 2 a similar state is formed by only very close in temperature to T N .
Open-Ended Attributions for the Performance of the Elderly.

The present study explored open-ended attributions for the success and failure of relatively younger and older men in social and academic situations using a between-subjects design. Attributions were collected from 109 college students and were coded using the Elig and Frieze scheme. Results showed that respondents were more likely to make attributions that combined age with other attributional categories (age-related attributions) than attributions solely to target's age. And, they made more ability-task interaction than ability attributions. Moreover, both attributions were as likely to be made for the elderly adult's success as his failure. Finally, differences also emerged in results from the stability dimension and those for age-related and ability-task attributions indicating that these parameters should be assessed independently in future research.
Using laddering to understand and leverage a brand’s equity

Understanding a brand’s equity is difficult for researchers. Building on means‐end theory, describes a method – laddering – which has proven useful in uncovering insights related to the source and the nature of a brand’s equity. Through laddering interviews, a meaningful “mental map” can be developed that visually links a brand’s attributes, the benefits or consequences of using it, and the personal values it satisfies. An analysis of 1,200 laddering interviews indicates that a combination of only seven basic values are at the core of most brand purchases. A number of illustrations of laddering insights and their implications for the marketing mix are given to show how laddering can help marketers understand and revitalize brand equity.
Counterattack reagents:hexamethyldisilane and 1,2-dimethyl-1,1,2,2-tetraphenyldisilane in the synthesis of polysilylated hydrazines

Abstract Polysilylated hydrazines have wide applicability. It is tedious to prepare these compounds by classic means. However, using hexamethyldisilane and 1,2-dimethyl-1,1,2,2-tetraphenyldisilane as counterattack reagents, we synthesized polysilylated hydrazines under alkaline conditions in good to excellent yields. This one-pot method is expedient and more efficient than other procedures. Polysilylated hydrazines were found to react with aldehydes or ketones in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate to give the corresponding hydrazones under anhydrous conditions.
Do Religious Proscriptions Matter?: Evidence from a Theory-Based Test

A large literature shows that religious participation is associated with various behaviors and outcomes, but researchers lack an accepted instrument for religion and have struggled to establish whether these associations are causal. Using the canonical economic model of religiosity, I develop an empirical test to investigate the importance of religious participation, in particular religious proscriptions and rules, on determining behavior. The test relies on exogenous variation in the cost of secular activities rather than an instrument for religious participation. Several empirical applications of this test are conducted; the results indicate a strong role for religious proscriptions in determining behavior.
Neutron star vortex dynamics and magnetic field decay: Implications for high density nuclear matter

Abstract We investigate the effect of the density-dependent proton and neutron gaps on vortex dynamics in neutron stars. We argue that the persistence of neutron star magnetic fields on timescales of 10 9 y suggests a superconducting gap curve with local maximum at intermediate density. We discuss the implications for exotic core phenomena such as pion/kaon condensation or a transition to quark matter.
Predicting Nonlinear Optical Properties of Delocalized Charge States in Polyenylic Chromophores and Dendrimers

Over the past several years there has been continuing interest in the design of highly conjugated monomers, oligomers and polymers for a variety of photonics applications dependent on a nonlinear response to intense laser radiation. Materials design criteria for these various applications depend on accurate structure-property relationships, and while these relationships can best be determined experimentally, computational approaches that can accurately predict trends in series are extremely useful in establishing target molecules having the desired photonic properties. We have recently reviewed the relationship between incorporation of polaronic or bipolaronic charge states in oligomeric or polymeric conjugation sequences’ and enhanced third-order optical nonlinearity, particularly for finite-length polyenes. In this presentation we will focus on how these charge states can be stabilized by electron-donating substituents in dithienylpolyenes, and in model dendrimers based on bis(diphenylamino)stilbene repeat units, and illustrate why these criteria are important for the design of new optical limiting chromophores.