cssi/SciSciGPT-SciSciNet huggingface dataset:
Resolving the Surfaces of Extrasolar Planets with Secondary Eclipse Light Curves

We present a method that employs the secondary eclipse light curves of transiting extrasolar planets to probe the spatial variation of their thermal emission. This technique permits an observer to resolve the surface of the planet withouttheneedtospatiallyisolateitslightfromthatofthecentralstar.Weevaluatethefeasibilityofthistechnique for the HD 209458 system by simulating observations made with the Spitzer Infrared Array Camera (IRAC). We consider two representations of the planetary thermal emission: a simple model parameterized by a sinusoidal dependence on longitude and latitude, and the results of a three-dimensional dynamical simulation of the planetary atmosphere previously published by Cooper & Showman. Wefind that observations of the secondary eclipse light curve are most sensitive to a longitudinal asymmetry in the dayside planetary emission. To quantify this signal, we define a new parameter,the‘‘uniformtimeoffset,’’whichmeasuresthetimelagbetweentheobservedsecondaryeclipseandthatpredictedbyaplanetwithspatiallyuniformemission.WecomparethepredictedamplitudeofthisparameterforHD20948 with the precision with which it could be measured with IRAC. We find that IRAC observations at 3.6� m of a single secondary eclipse should permit sufficient precision to confirm or reject the Cooper & Showman model of the surface fluxdistributionforthisplanet.Wequantifythesignal-to-noiseratioforthisoffsetintheremainingIRACbandsandfind that a modest improvement in photometric precision should permit a similarly robust detection. Subjectheadinggbinaries:eclipsing — infrared:stars — planetarysystems — stars:individual(HD 209458) — techniques: high angular resolution — techniques: photometric
Effective detection of nonsplit module extensions

Abstract Let n be a positive integer, and let R be a finitely presented (but not necessarily finite dimensional) associative algebra over a computable field. We examine algorithmic tests for deciding (1) if every at most- n -dimensional representation of R is semisimple, and (2) if there exist nonsplit extensions of non-isomorphic irreducible R -modules whose dimensions sum to no greater than n .
Mild amidation of aldehydes with amines mediated by lanthanide catalysts

Catalytic amidation of aldehydes with amines is efficiently mediated by homoleptic lanthanide amido complexes, Ln[N(SiMe3)2]3 (Ln = La, Sm, and Y). Amidation reactivity follows the trend: La > Sm ≈ Y. These reactions proceed in high yield without added oxidants, bases, and/or heat or light, which are usually required in other catalytic amidation processes. The reaction is demonstrated with a variety of amines, with yields as high as 98% based on amine.
Variable Parameter Nutation Damper for SAS-A

This paper presents design objectives, functional description and in-flight performance of a variable parameter nutation damper for a dual-spin satellite. The damper consists of a torsion wire mounted pendulum which includes the capability of command changing the pendulum resonant frequency and damping constant in order to obtain optimum spin axis stabilization for both a dual-spin and single-spin spacecraft dynamical condition. State-of-theart features of this damper include: 1) taut-band suspension, for a pendulous mass, which has no mechanical friction of hysteresis, 2) magnetic circuit for changing the torque constant of the taut-band thereby changing the damper natural frequency, 3) chargeable magnet system for varying the damping coefficient, and 4) 7-bit optical readout for telemetering the damper motion. The damper weights 2.7 Ib and draws 20 mw power when functioning for dual-spin conditions. The minimum nutation damping time constant in this mode is 12 min with a predicted spin axis pointing accuracy of 1 min of arc. Stabilization to better than 2 min of arc has been achieved in orbit.
Tail probabilities for infinite series of regularly varying random vectors

A random vector $X$ with representation $X=∑_{j≥0}A_jZ_j$ is considered. Here, $(Z_j)$ is a sequence of independent and identically distributed random vectors and $(A_j)$ is a sequence of random matrices, ‘predictable’ with respect to the sequence $(Z_j)$. The distribution of $Z_1$ is assumed to be multivariate regular varying. Moment conditions on the matrices $(A_j)$ are determined under which the distribution of $X$ is regularly varying and, in fact, ‘inherits’ its regular variation from that of the $(Z_j)$’s. We compute the associated limiting measure. Examples include linear processes, random coefficient linear processes such as stochastic recurrence equations, random sums and stochastic integrals.
F-14 Inlet Development Experience

This paper reviews the F-14 inlet design and discusses the wind tunnel and flight test results of investigation that can contribute to move advanced inlet design.
Where Exactly Are the Arcs of Neptune

Abstract We show that periodic close encounters between Neptune's arc particles and the nearby satellite Galatea lead to a usually neglected secular perturbation on the osculating longitude at epoch (e). This perturbation changes the effective mean motion (i.e., the mean motion averaged over a synodic period or longer). The correction is 0.0041°/day, which displaces the arcs 0.2 km farther away from Galatea than was previously calculated by C. C. Porco (1991, Science 253, 995), and also modifies the location of the arc-confining resonances by an equivalent amount. We examine this perturbation both analytically and numerically and demonstrate that the confinement mechanism based on single-satellite shepherding by Galatea (C. C. Porco, 1991, Science 253, 995) remains operational at the new position.
Supply Dynamics in the U.S. Hog Industry

A variety of methods and empirical techniques are now available for estimating dynamic economic relationships. Unfortunately, most dynamic modeling procedures rely heavily on the sample data for specification. This is due to a lack of a priori information useful for determining the appropriate lag structure. However, there is frequently a rich source of information that can be used to define lag structures in agricultural supply models. This information is related to the biological and physiological processes characterizing agricultural production. In this paper, a quarterly econometric model of supply response in the U.S. hog industry is specified and estimated. This model incorporates relevant biological features of hog production directly into the specification. The structural integrity of the model is evaluated by examining post-sample predictive ability and mean-path elasticities. The results indicate performance that is consistent with observed behavior in the U.S. hog industry. Nous disposons aujourd'hui de toute une gamme de methodes et de techniques empiriques pour ľestimation des rapports economiques dynamiques. Malheureusement, la plupart des methodes de modelisation dynamique dependent etroitement, pour leurs specifications, sur des donnees echantillonnees. Ceci decoule ďun manque ďinformations a priori utiles pour la determination de la structure de retard appropriee. Toutefois, on dispose frequemment ďune riche source ďinformations qui peuvent servir a definir les structures de retard dans les modeles de ľoffre en agriculture. Cette information est liee aux processus biologiques et physiologiques caracterisant la production agricole. Dans le present document, nous procedons a la specification et a ľestimation ďun modele econometrique trimestriel du comportement de ľoffre dans le secteur americain du pore. Ce modele incorpore directement dans la specification les caracteristiques biologiques pertinentes de la production porcine. Nous evaluons ľintegrite structurale du modele en examinant ľaptitude predictive post-echantillonnage et les valeurs moyennes ďelasticite. Nos resultats laissent conclure a une performance qui vient corroborer le comportement observe dans le secteur americain du porc.
Modeling radar scattering from icy lunar regoliths

Scientific context: The data from two orbital synthetic aperture radars-the Chandrayaan Mini-RF, at 13-cm wavelength (S-band) and the Lunar Reconnaissance Orbiter Mini-RF at 4 cm and 13 cm (X-band)-can provide evidence of presence of ice deposits in the polar shadowed areas. The performance and scientific return from those two experiments require that we understand the radar backscattering characteristics of the icy lunar regoliths sufficiently to assess the possibility of frozen volatiles in the surface and shallow subsurface (defined here as 10 times the wavelength). If ices in the permanently shadowed areas of the lunar poles have the radar characteristics similar to the ices on Mercury, Mars and the Galilean satellites, then these ices will have a substantial radar enhancement characterized by a circular polarization ratio (CPR) greater than unity. Here we examine the possibilities that this distinct CPR signature may be diminished by factors such as a thin regolith covering the ice, the ice occupying small patches within a larger radar pixel and/or the high CPRs resulting from blocky crater ejecta.
The CNN problem and other k -server variants

We study several interesting variants of the k-server problem. In the CNN problem, one server services requests in the Euclidean plane. The difference from the k-server problem is that the server does not have to move to a request, but it has only to move to a point that lies in the same horizontal or vertical line with the request. This, for example, models the problem faced by a crew of a certain News Network trying to shoot scenes on the streets of Manhattan from a distance; for any event at an intersection, the crew has only to be on a matching street or avenue. The CNN problem contains as special cases two important problems: the BRIDGE problem, also known as the cow-path problem, and the weighted 2-server problem in which the 2 servers may have different speeds. We show that any deterministic online algorithm has competitive ratio at least 6 + √17. We also show that some successful algorithms for the k-server problem fail to be competitive. In particular, no memoryless randomized algorithm can be competitive.We also consider another variant of the k-server problem, in which servers can move simultaneously, and we wish to minimize the time spent waiting for service. This is equivalent to the regular k-server problem under the L∞ norm for movement costs. We give a ½ k(k + 1) upper bound for the competitive ratio on trees.
The Preparation of 5-Aryl-5-methyl-4,5-dihydroisoxazoles from Dilithiated C(α), O -Oximes and Select Acetyl Ketones

Abstract Several 5-aryl-5-methyl-4,5-dihydroisoxazoles were prepared by a three-step, one-pot process in 24–83% yield. C(α),O-oximes were dilithiated with lithium diisopropylamide and condensed with electron enriched acetophenones, such as 4′-methoxyacetophenone, followed by immediate acid cyclization.
Intra-Ethnic Diversity in Hispanic Child Mortality, 1890–1910 *

Using a representative sample of the Hispanic population of the United States based on the manuscripts of the 1910 census, we estimate childhood mortality for the period from approximately 1890 to 1910. We find high child mortality in the Hispanic population, higher than for non-Hispanic whites but not significantly different than among nonwhite non-Hispanics (mostly African Americans). Hispanic rural farm populations in California, Texas, and Arizona experienced high mortality, but not as high as other Hispanic populations. Child mortality was very high among Hispanic residents of New Mexico and those in Florida outside Tampa; it was especially low in the Hispanic population in Tampa.
Separating Maximally Violated Comb Inequalities in Planar Graphs

The Traveling Salesman Problem TSP is a benchmark problem in combinatorial optimization. It was one of the very first problems used for developing and testing approaches to solving large integer programs, including cutting plane algorithms and branch-and-cut algorithms. Much of the research in this area has been focused on finding new classes of facets for the TSP polytope, and much less attention has been paid to algorithms for separating from these classes of facets. In this paper, we consider the problem of finding violated comb inequalities. If there are no violated subtour constraints in a fractional solution of the TSP, a comb inequality may not be violated by more than 1. Given a fractional solution in the subtour elimination polytope whose graph is planar, we either find a violated comb inequality or determine that there are no comb inequalities violated by 1. Our algorithm runs in On + MCn time, where MCn is the time to compute a cactus representation of all minimum cuts of a weighted planar graph on n vertices.
Preparation and properties of amido halide complexes of niobium and tantalum and their reactions with alkynes

Abstract A one-step procedure for the preparation of new mixed-amido halides of niobium and tantalum from their pentahalides and the trimethylsilylamine reagent
Time varying networks and the weakness of strong ties

In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the temporal evolution of users' egocentric networks. We encode this observation in a reinforcement process defining a time-varying network model that exhibits the emergence of strong and weak ties. We study the effect of time-varying and heterogeneous interactions on the classic rumour spreading model in both synthetic, and real-world networks. We observe that strong ties severely inhibit information diffusion by confining the spreading process among agents with recurrent communication patterns. This provides the counterintuitive evidence that strong ties may have a negative role in the spreading of information across networks.
An Update on the Status of the NIF Power-Conditioning System

The National Ignition Facility (NIF) power-conditioning system provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 main energy-storage modules (MESMs) stores up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400- pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. The production, installation, commissioning, and operation of the NIF power conditioning continue to progress rapidly, with the goals of completing accelerated production and commissioning by early 2008, while maintaining an aggressive operation schedule. To date, more than 97% of the required modules have been assembled, shipped, and installed in the facility, representing more than 380 MJ of stored energy available for driving the NIF flashlamps. The MESMs have displayed outstanding reliability during daily multiple-shift operations.
Computational investigation of the ortho-lithiation reaction mechanism of substituted cubanes

Abstract Two possible reaction intermediates of the ortho-lithiation of 1-phenyl-2-N,N-dimethylcubane carboxamide were investigated using an ab-initio SCF molecular orbital approach at STO-5G level. The molecular electrostatic potential was used to analyze the reactivity of these intermediates. The geometry of the key intermediates is discussed. Based on the relative stability and the strength of the negative electrostatic potential near the reactive site criteria, it is quite clear that this reaction proceeds via a five-membered ring intermediate. The results agree well with experimental findings.
Detector Problems at the SSC

During the last couple of years there has been considerable concern expressed among the US high energy community as to whether detector limitations would prevent one from being able to fully exploit a luminosity of 10/sup 33/ cm/sup -2/ sec/sup -1/ at a hadron-hadron high energy collider. As a result of these concerns, a considerable amount of work has been done recently in trying to understand the nature of potential difficulties and the required R and D that needs to be performed. A lot of this work has been summarized in the 1984 DPF Summer Study at Snowmass. This paper attempts to review some of these results. This work is limited to the discussion of detector problems associated with the study of high energy hadron-hadron collisions. We shall start with the discussion of the desirable features of the detectors and of the SSC environment in which they will have to work. After a brief discussion of the model 4..pi.. detectors, we shall discuss specific detector aspects: lepton identification, tracking, calorimetry and computing and triggering. We shall end with some remarks about possible future course of events. 15 refs., 10 figs.
Computers, security, and the audit function

As the role of computation spread in the world of commercial data processing and in the world of organizational administration, concern and attention were directed toward such matters as programming techniques, computer capabilities, and computer performance measurement and evaluation. However, because computers became increasingly essential to the conduct of an organization's daily activities, and because these systems frequently controlled vast amounts of organizational resources, the computer became an object of attack. In some cases the organization was the target; the computer was the means to attack it. In other cases personal gain was the goal; the computer was merely the means for misappropriating corporate assets. Parker has chronicled more than two hundred cases of computer-related crimes. Therefore, concern has recently been focused on the security of computer installations and the maintenance of computer system integrity. In 1974 both AFIPS and the National Bureau of Standards have published guidelines for computer security.
Tiling properties of spectra of measures

We investigate tiling properties of spectra of measures, i.e., sets \(\Lambda \) in \(\mathbb {R}\) such that \(\{e^{2\pi i \lambda x}{:}\, \lambda \in \Lambda \}\) forms an orthogonal basis in \(L^2(\mu )\), where \(\mu \) is some finite Borel measure on \(\mathbb {R}\). Such measures include Lebesgue measure on bounded Borel subsets, finite atomic measures and some fractal Hausdorff measures. We show that various classes of such spectra of measures have translational tiling properties. This lead to some surprizing tiling properties for spectra of fractal measures, the existence of complementing sets and spectra for finite sets with the Coven–Meyerowitz property, the existence of complementing Hadamard pairs in the case of Hadamard pairs of size 2, 3, 4 or 5. In the context of the Fuglede conjecture, we prove that any spectral set is a tile, if the period of the spectrum is 2, 3, 4 or 5.
A high-pressure phase transition of calcite-III

We document the presence of a high pressure phase transition in metastable calcite-III using infrared spectroscopy. The post-calcite-III transition initiates at a pressure of 15.5 (′2) GPa, and is completed between 25 and30 GPa. The transition is particularly apparent in the ν 4 -in-plane bending vibration of the carbonate group, in which two new peaks progressively supplant the doublet associated with calcite-III. Additionally, both the ν 3 -asymmetric and ν 1 -symmetric stretches of the carbonate group in the high-pressure phase occur at substantially lower frequencies than the extrapolated positions of the corresponding calcite-III peaks. The geometry of the carbonate unit within the high-pressure phase is likely closer to trigonal symmetry than in the calcite-III structure, and the C-O bond is probably longer than in the lower pressure calcite-III phase.
Photothermal bleaching in time-lapse photoacoustic microscopy

We studied the phenomenon of photothermal bleaching — a gradual reduction of contrast agent particles during repeated scans in photoacoustic microscopy. The dependence of the photothermal bleaching rate on the excitation pulse energy was determined while the laser focal diameter was held constant. Our results showed that, the dependence of the photothermal bleaching rate on the excitation pulse energy differed before and after the absorbers were raised to their melting point by the deposited laser energy. Based on this finding, we suggested an optimal excitation pulse energy, which balances the photothermal bleaching rate and signal amplitude, for time-lapse imaging applications.
The Future of the American Labor Movement

Coming at a time of profound change in the global conditions under which American organized labor exists, The Future of the American Labor Movement, first published in 2002, describes and analyzes labor's strategic alternatives. The analysis is broadly cast, taking into account ideas that range from the current European Social Dialogue to the methods of the nineteenth-century American Knights of Labor. There are a number of intriguing strategies that have potential for reviving the labor movement in the United States, of which worker ownership and labor capital strategies are examples. This book demonstrates the necessity for a number of diverse strategies to be pursued simultaneously. For this to work, one has to think in terms of a broad movement of labor, consisting of diverse parts, held together by a clear idea of its purpose and a new structure.
A neural network controller for systems with unmodeled dynamics with applications to wastewater treatment

This paper considers the use of neural networks (NN's) in controlling a nonlinear, stochastic system with unknown process equations. The approach here is based on using the output error of the system to train the NN controller without the need to assume or construct a separate model (NN or other type) for the unknown process dynamics. To implement such a direct adaptive control approach, it is required that connection weights in the NN be estimated while the system is being controlled. As a result of the feedback of the unknown process dynamics, however, it is not possible to determine the gradient of the loss function for use in standard (backpropagation-type) weight estimation algorithms. In principle, stochastic approximation algorithms in the standard (Kiefer-Wolfowitz) finite-difference form can be used for this weight estimation since they are based on gradient approximations from available system output errors. However, these algorithms will generally require a prohibitive number of observed system outputs. Therefore, this paper considers the use of a new stochastic approximation algorithm for this weight estimation, which is based on a "simultaneous perturbation" gradient approximation. It is shown that this algorithm can greatly enhance the efficiency over more standard stochastic approximation algorithms based on finite-difference gradient approximations. The approach is illustrated on a simulated wastewater treatment system with stochastic effects and nonstationary dynamics.
A Long-Run Risks Model of Asset Pricing with Fat Tails ∗

We explore the effects of fat tails on the equilibrium implications of the long run risks model of asset pricing by introducing innovations with dampened power law to consumption and dividends growth processes. We estimate the structural parameters of the proposed model by maximum likelihood. We find that the stochastic volatility model with fat tails can generate implied risk premium, expected risk free rate and their volatilities comparable to the magnitudes observed in data. The model with fat tails leads to a significant increase in implied risk premia over the benchmark Gaussian model, but similar risk free rate and its volatility, as well as that of market returns and price-dividend ratios.
Application of Transparent Enclosure Theory to Solar Energy Absorption by Cylindrical Tubes in Sunspaces

A general matrix formulation for beam and diffuse radiative solar transfer is presented for an enclosure containing partially transparent walls. The general theory is used to study the absorption of radiatn solar energy in a building sunspace having a south-facing window and a row of opaque vertical cylindrical-tube solar absorbers. A two-dimensional model is formulated for the sunspace in which a typical cylindrical absorber tube is subdivided into a number of uniform elements and the window and sunspace surfaces are each represented as single elements. The matrix expressions are evaluated for incident solar flux conditions typical for a south vertical window on a clear winter day. The results are presented as dimensionless ratios of absorbed-to-incident solar flux as a function of the tube spacing to radius ratio. The spatial distribution of absorbed solar flux is presented at discrete time interals for the cylindrical tube. Space and time-averaged values of absorbed solar flux are also presented for the cylinder, the window, and the room. The potential application of these results for thermal modeling in passive solar applications is discussed.
The dipole anisotropy of the first all-sky X-ray cluster sample

We combine the recently published CIZA galaxy cluster catalogue with the XBACs cluster sample to produce the first all-sky catalogue of X-ray clusters in order to examine the origins of the Local Group’s peculiar velocity without the use of reconstruction methods to fill the traditional Zone of Avoidance. The advantages of this approach are (i) X-ray emitting clusters tend to trace the deepest potential wells and therefore have the greatest effect on the dynamics of the Local Group and (ii) our all-sky sample provides data for nearly a quarter of the sky that is largely incomplete in optical cluster catalogues. We find that the direction of the Local Group’s peculiar velocity is well aligned with the CMB as early as the Great Attractor region 40 h −1 Mpc away, but that the amplitude of its dipole motion is largely set between 140 and 160 h −1 Mpc. Unlike previous studies using galaxy samples, we find that without Virgo included, roughly � 70% of our dipole signal comes from mass concentrations at large distances (> 60 h −1 Mpc) and does not flatten, indicating isotropy in the cluster distribution, until at least 160 h −1 Mpc. We also present a detailed discussion of our dipole profile, linking observed features to the structures and superclusters that produce them. We find that most of the dipole signal can be attributed to the Shapley supercluster centered at about 150 h −1 Mpc and a handful of very massive individual clusters, some of which are newly discovered and lie well in the Zone of Avoidance. Subject headings: cosmic microwave background — galaxies: clusters: general — large-scale structure of universe — X-rays: galaxies: clusters
Statistics of depleted flux tubes in the jovian magnetosphere

Abstract On many of its passes through the Io torus the Galileo spacecraft has detected the presence of what appear to be thin magnetic flux tubes with fields somewhat higher than their surroundings. On these flux tubes the magnetic pressure is sufficiently above the pressure of neighboring tubes that it is possible the plasma contributions to the pressure within these tubes are depleted. Due to their short duration, they are only detectable in high time-resolution magnetometer data. Herein we survey all high time-resolution data that are available over the full Galileo mission and present a final statistical study. These tubes occupy 0.32% of the torus outside the orbit of Io. None are found inside. Their strength indicates that the ratio of the thermal pressure to magnetic pressure in the outer torus is about 2%. Comparison of the observed electron density in the neighborhood of these tubes indicates that the ion temperature is in the range 30–100 eV, consistent with other estimates. The amount of magnetic flux transported by these thin tubes could supply the amount of magnetic flux mass-loaded and transported to the magnetotail if the inward velocity is about 300 times that of the outward transport. Finally, the thin flux tubes are found in clusters, as they would occur if they resulted from the breakup of larger flux tubes.
Potential for use of high-temperature superconductors in fusion reactors*

The present rate of development of high-temperature superconductors (HTSs) is sufficiently rapid that there may be opportunities for their use in contemporary fusion devices such as the International Thermonuclear Experimental Reactor (ITER). The most likely application is for delivering power to the superconducting magnets, especially in substituting for the current leads between the temperatures of 4 and 77 K. A second possible application of HTSs is in a liquid-nitrogen-cooled power bus connecting the power supplies to the magnets, thus reducing ohmic heating losses in these relatively long cables. A third potential application of HTSs is in inner high-field windings of the toroidal field coils that would operate at ~ 20 K. While the use of higher temperature magnets offers significant advantages to the reactor system, it is unlikely that tested HTSs for this application will be available within the ITER time frame.
Low-temperature Galactic fountains

Analytic and one- and two-dimensional hydrodynamic calculations are performed to determine whether or not the Galactic fountain model can explain observations of neutral gas in the Galactic halo. Galactic halo gasdynamics are examined, including thermal conduction, Galactic rotation, and Galactic fountains. Results are presented from numerical modeling of low-temperature Galactic fountains. It is found that the best reproduction of the observations is provided by a model near the transonic regime with a temperature and density at the base of the fountain of 300,000 K and 0.001/cu cm, respectively. The cooling time for the hot gas is 33 million yr and the time for newly formed clouds to return to the disk is 47 million yr, neglecting drag forces.
ANALYZING STOCK MARKET VOLATILITY USING EXTREME-DAY MEASURES

We develop a simple measure of volatility based on extreme-day returns and apply it to market returns from 1885 to 2002. Because returns are not normally distributed, the extreme-day measure, which is distribution free, might provide a better measure of stock market risk than the traditional standard deviation. The extreme-day measure more accurately explains investor behavior relative to standard deviation as shown by equity fund flows, and we find evidence that large negative changes appear to influence investor behavior more than large positive changes.
Solving problems by formula manipulation in logic and linear inequalities

Using formal logic, many problems from the general area of linear inequalities can be expressed in the elementary theory of addition on the real numbers (EAR). We describe a method for eliminating quantifiers in EAR which has been programmed and demonstrate its usefulness in solving some problems related to linear programming. In the area of mechanical mathematics this kind of approach has been neglected in favor of more generalized methods based on Herbrand expansion. However, in a restricted area, such as linear inequalities, the use of these specialized methods can increase efficiency by several orders of magnitude over an axiomatic Herbrand approach, and make practical problems accessible.
Gas Shepherding by an Infalling Satellite

I calculate the action of a satellite, infalling through dynamical friction, on a coplanar gaseous disk of finite radial extent. The disk tides, raised by the infalling satellite, couple the satellite and disk. Dynamical friction acting on the satellite then shrinks the radius of the coupled satellite-disk system. Thus, the gas is "shepherded" to smaller radii. In addition, gas shepherding produces a large surface density enhancement at the disk edge. If the disk edge then becomes gravitationally unstable and fragments, it may give rise to enhanced star formation. On the other hand, if the satellite is sufficiently massive and dense, the gas may be transported from ~100 pc to inside of 10 to tens of parsecs before completely fragmenting into stars. I argue that gas shepherding may drive the fueling of active galaxies and central starbursts, and I compare this scenario to competing scenarios. I argue that sufficiently large and dense super star clusters (acting as the shepherding satellites) can shepherd a gas disk down to 10 to tens of parsecs. Inside of 10 to tens of parsecs, another mechanism may operate, i.e., cloud-cloud collisions or a marginally (gravitationally) stable disk, that drives the gas 1 pc, where it can be viscously accreted, feeding a central engine.
Evolution in minority games. (I). Games with a fixed strategy space

In this paper we study the minority game in the presence of evolution. In particular, we examine the behavior in games in which the dimension of the strategy space, m, is the same for all agents and fixed for all time. We find that for all values of m, not too large, evolution results in a substantial improvement in overall system performance. We also show that after evolution, results obey a scaling relation among games played with different values of m and different numbers of agents, analogous to that found in the non-evolutionary, adaptive games. Best system performance still occurs, for a given number of agents, at mc, the same value of the dimension of the strategy space as in the non-evolutionary case, but system performance is now nearly an order of magnitude better than the non-evolutionary result. For m<mc, the system evolves to states in which average agent wealth is better than in the random choice game, despite (and in some sense because of) the persistence of maladaptive behavior by some agents. As m gets large, overall systems performance approaches that of the random choice game.
Predicting health behaviors with an experimental measure of risk preference

We conduct a large-scale economics experiment paired with a survey to examine the association between individual risk preference and health-related behaviors among adults aged 18-87 years. Risk preference is measured by the lottery choice experiment designed by Holt and Laury [Holt, C.A., Laury, S.K., 2002. Risk aversion and incentive effects. The American Economic Review 92(5), 1644-1655]. Controlling for subject demographic and economic characteristics, we find that risk aversion is negatively and significantly associated with cigarette smoking, heavy drinking, being overweight or obese, and seat belt non-use. In additional specifications, we find that risk aversion is negatively and significantly associated with the likelihood a subject engaged in any of five risky behaviors and the number of risky behaviors reported.
The Major Sources of the Cosmic Reionizing Background at z ~ 6

In this Letter, we address which sources contributed most of the reionizing photons. Our argument assumes that the reionization ended around z 6 and that it was a relatively quick process, i.e., that there was a nonnegligible fraction of neutral hydrogen in the universe at somewhat earlier epochs. Starting from our earlier estimate of the luminosity function (LF) of galaxies at z 6, we quantitatively show that the major sources of reionization are most likely galaxies with L < L*. Our approach allows us to put stronger constraints to the LF of galaxies at z 6. To have the universe completely ionized at this redshift, the faint-end slope of the LF should be steeper than α = -1.6, which is the value measured at lower redshifts (z 3), unless either the normalization (Φ*) of the LF or the clumping factor of the ionized hydrogen has been significantly underestimated. If Φ* is actually lower than what we assumed by a factor of 2, a steep slope close to α = -2.0 is required. Our LF predicts a total of 50-80 z 6 galaxies in the Hubble Space Telescope Ultra Deep Field to a depth of AB = 28.4 mag, which can be used to constraint both Φ* and α. We conclude that the least luminous galaxies existing at this redshift should reach as low as some critical luminosity in order to accumulate the entire reionizing photon budget. On the other hand, the existence of significant amounts of neutral hydrogen at slightly earlier epochs, e.g., z 7, requires that the least luminous galaxies should not be fainter than another critical value (i.e., the LF should cut off at this point).
MLE+: a tool for integrated design and deployment of energy efficient building controls

Simulation engines for buildings can be realistic and accurate, but only provide basic control interfaces. Control engineers have developed robust and complex controls for energy-efficient building operation though such methods are often based on simplistic physical models. To address this issue, we developed MLE+, a tool for energy-efficient building automation design, co-simulation and analysis. This tool leverages the high-fidelity plant simulation capabilities of EnergyPlus building modeling software and the scientific computation and design capabilities of Matlab/Simulink for controller design. MLE+ facilitates integrated building simulation and controller formulation with integrated support for system identification, control design, optimization, simulation analysis and communication between software applications and building equipment. MLE+ has been successfully used to generate schedules for building HVAC control systems for peak power minimization.
Analysis of Force Shape Characteristics and Detection of Depth-of-Cut Variations in End Milling

This paper proposes an analytical approach to detect depth-of-cut variations based on the cutting-force shape characteristics in end milling. Cutting forces of a single-flute end mill are analyzed and classified into three types according to their shape characteristics. Cutting forces of a multiple-flute end mill are then classified by considering both the cutting types of the corresponding single-flute end mill and the degree of overlap of successive flutes in the cut. Force indices are extracted from the cutting forces and depth-of-cut variations are detected based on the changes of the force shape characteristics via the force indices in an end-milling process. The detection methodology is validated through cutting experiments.
The Development of Efficient Protocols for the Palladium-Catalyzed Cyclization Reactions of Secondary Amides and Carbamates

With the proper choice of palladium catalyst, ligand, and base, five-, six-, and seven-membered rings are formed efficiently from secondary amide or secondary carbamate precursors, offering significant improvements to currently existing methodology.
Effect of Foams Used During Carbonate Acidizing

Although acidization has been used successfully for many years to increase the productivity of petroleum wells in carbonate formations, demands on the performance and application of the acidizing process are increasing. This paper investigates a method of in-situ foam generation that allows deeper wormhole penetration yet uses less acid than conventional methods. The dissolution patterns were imaged with neutron radiography, which provided an in-depth understanding of the effects of foam and other critical parameters. Results show that foam is effective in promoting efficient stimulation, even at low acid injection rates.
Response of Regional Seismicity to the Static Stress Change Produced by the Loma Prieta Earthquake

The 1989 Loma Prieta, California, earthquake perturbed the static stress field over a large area of central California. The pattern of stress changes on major faults in the region predicted by models of the earthquake9s dislocation agrees closely with changes in the regional seismicity rate after the earthquake. The agreement is best for models with low values of the coefficient of friction (0.1 ≤ µ ≤ 0.3) on Bay Area faults. Both the stress models and measurements suggest that stresses were increased on the San Andreas fault north of the Loma Prieta rupture, but decreased slightly on the Hayward fault. This relaxation does not warrant lower probability estimates for large earthquakes on the Hayward fault in the next 30 years, however.
Chaos and Energy Spreading for Time-Dependent Hamiltonians, and the Various Regimes in the Theory of Quantum Dissipation

Abstract We make the first steps toward a generic theory for energy spreading and quantum dissipation. The Wall formula for the calculation of friction in nuclear physics and the Drude formula for the calculation of conductivity in mesoscopic physics can be regarded as two special results of the general formulation. We assume a time-dependent Hamiltonian H ( Q , P ; x ( t )) with x ( t )= Vt , where V is slow in a classical sense. The rate-of-change V is not necessarily slow in the quantum-mechanical sense. The dynamical variables ( Q , P ) may represent some “bath” which is being parametrically driven by x . This bath may consist of just a few degrees of freedom, but it is assumed to be classically chaotic. In the case of either the Wall or Drude formula, the dynamical variables ( Q , P ) may represent a single particle. In any case, dissipation means an irreversible systematic growth of the (average) energy. It is associated with the stochastic spreading of energy across levels. The latter can be characterized by a transition probability kernel P t ( n ∣ m ), where n and m are level indices. This kernel is the main object of the present study. In the classical limit, due to the (assumed) chaotic nature of the dynamics, the second moment of P t ( n ∣ m ) exhibits a crossover from ballistic to diffusive behavior. In order to capture this crossover within quantum mechanics, a proper theory for the quantal P t ( n ∣ m ) should be constructed. We define the V regimes where either perturbation theory or semiclassical considerations are applicable in order to establish this crossover. In the limit ℏ→0 perturbation theory does not apply but semiclassical considerations can be used in order to argue that there is detailed correspondence, during the crossover time, between the quantal and the classical P t ( n ∣ m ). In the perturbative regime there is a lack of such correspondence. Namely, P t ( n ∣ m ) is characterized by a perturbative core-tail structure that persists during the crossover time. In spite of this lack of (detailed) correspondence there may be still a restricted correspondence as far as the second moment is concerned. Such restricted corre- spondence is essential in order to establish the universal fluctuation-dissipation relation.
Whitehead doubling persists.

The operation of (untwisted) Whitehead doubling trivializes the Alexander module of a knot (and consequently, all known abelian invariants), and converts knots to topologically slice ones. In this note we show that Whitehead doubling does not trivialize the rational function that equals to the 2-loop part of the Kontsevich integral.
Developing Radio Beam Geometry and Luminosity Models of Pulsars

Our recent studies of pulsar population statistics suggest that improvements of radio and gamma-ray beam geometry and luminosity models require further refinement. The goal of this project is to constrain the viewing geometry for some radio pulsars, especially three-peaked pulse profiles, in order to limit the uncertainty of the magnetic inclination and impact angles. We perform fits of the pulse profile and position angle sweep of radio pulsars for the available frequencies. We assume a single core and conal beams described by Gaussians. We incorporate three different size cones with frequency dependence from the work of Mitra & Deshpande (1999). We obtain separate spectral indices for the core and cone beams and explore the trends of the ratio of core to cone peak fluxes. This ratio is observed to have some dependence with period. However, we cannot establish the suggested functional form of this ratio as indicated by the work of Arzoumanian, Chernoff & Cordes (2002).
A Spectroscopic Technique for Measuring Stellar Properties of Pre-Main-Sequence Stars

We describe a technique for deriving effective temperatures, surface gravities, rotation velocities, and radial velocities from high-resolution near-IR spectra. The technique matches the observed near-IR spectra to spectra synthesized from model atmospheres. Our analysis is geared toward characterizing heavily reddened pre–main-sequence stars, but the technique also has potential applications in characterizing main-sequence and post–main-sequence stars when these lie behind thick clouds of interstellar dust. For the pre–main-sequence stars, we use the same matching process to measure the amount of excess near-IR emission (which may arise in the protostellar disks) in addition to the other stellar parameters. The information derived from high-resolution spectra comes from line shapes and the relative line strengths of closely spaced lines. The values for the stellar parameters we derive are therefore independent of those derived from low-resolution spectroscopy and photometry. The new method offers the promise of improved accuracy in placing young stellar objects on evolutionary model tracks. Tests with an artificial noisy spectrum with typical stellar parameters and a signal-to-noise ratio of 50 indicate a 1 σ error of 100 K in Teff, 2 km s-1 in v sin i, and 0.13 in continuum veiling for an input veiling of 1. If the flux ratio between the sum of the Na, Sc, and Si lines at 2.2 μm and the (2–0) 12CO band head at 2.3 μm is known to an accuracy of 10%, the errors in our best-fit value for log g will be Δ log g = 0.1–0.2. We discuss the possible systematic effects on our determination of the stellar parameters and evaluate the accuracy of the results derivable from high-resolution spectra. In the context of this evaluation, we quantitatively explore the degeneracy between temperature and gravity that has bedeviled efforts to type young stellar objects using low-resolution spectra. The analysis of high-resolution near-IR spectra of MK standards shows that the technique yields very accurate values for the effective temperature. The greatest uncertainty in comparing our results with optical spectral typing of MK standards is in the spectral type–to–effective temperature conversion for the standards themselves. Even including this uncertainty, the 1 σ difference between the optical and infrared temperatures for dwarfs at 3000–5800 K is only 140 K. In a companion paper, we present an analysis of heavily extincted young stellar objects in the ρ Ophiuchi molecular cloud.
Coherence of resonant-tunneling transport in terahertz quantum-cascade lasers

We develop simple density-matrix models to describe the role of coherence in resonant-tunneling (RT) transport of quantum-cascade lasers (QCLs). Specifically, we investigate the effects of coherent coupling between the lasing levels with other levels on the transport properties and gain spectra. In the first part of the paper, we use a three-level density-matrix model to obtain useful analytical expressions for current transport through the injector barrier in a QCL. An expression for the slope discontinuity in the current-voltage characteristics at the lasing threshold is derived. This value is shown to be a direct measure of the population inversion at threshold and contradicts the previously held belief of it being indicative of ratio of the laser level lifetimes. In the second part of the paper, we use density matrices to compute the gain spectrum for a resonant-phonon terahertz QCL design. The large anticrossing of the doublet of lower radiative levels is reflected in a broad gain linewidth due to a coherent RT assisted depopulation process. At certain bias conditions, the gain spectrum exhibits double peaks which is supported by experimental observations.