cssi/SciSciGPT-SciSciNet huggingface dataset:
A Method of Orbit Determination Using Overlapping Television Pictures

A method that utilizes the Mariner Mars 1969 television pictures has been developed to aid in the post-encounter determination of the TV viewing directions. A weighted least-squares estimation scheme is used, based on observation of common Mars surface features in over- lapping TV pictures. Estimates were also obtained for the encounter orbits of Mariners VI and VII, and also for the orientation of the Mars spin axis; however, the estimated solutions for the spacecraft orbits and for the spin axis did not result in a reduction of the a priori un- certainties in these parameters. Good results were obtained for the estimated corrections and the a posteriori uncertainties of the nominal TV viewing directions. 7T10 determine the locations on Mars of the Mariner near- JL encounter TV pictures, accurate determinations of the camera viewing directions are required. Also required are accurate determinations of the encounter orbits and the orien- tation of the Mars spin axis. Highly accurate estimates of the camera pointing angles can be obtained from telemetered readouts of the commanded angle settings and spacecraft attitude. However, the Mariner VII spacecraft experienced an anomaly shortly before arriving at Mars. The anomaly corrupted the radio tracking data for a short time and dam- aged the telemetry channel which described one of the camera pointing angles. Thus, a need arose to refine the nominal encounter estimates of the Mariner VII camera pointing angles. A method was developed for estimating corrections to the nominal camera pointing angles, and also the spacecraft en- counter orbits and the Mars spin axis. The method utilizes the overlapping television pictures which were obtained dur- ing each Mariner '69 flyby, and the weighted-least-squares estimation technique. Solutions were obtained for both Mariner VI and VII parameters. The method can be summarized as follows. In two or more overlapping TV pictures, one identifies a number of surface features which lie in the overlap region. The picture co- ordinates of each feature in each picture are then measured. The aerocentric latitude and longitude of each feature in each overlapping picture are computed from the measured co- ordinates and a set of nominal parameters which describe the camera orientation, the times of the picture shutterings, the spacecraft orbit, and the Mars spin axis and planet radius. The same feature in two or more pictures should have the same computed values of latitude and longitude. However, differences in the computed values will result because of the presence of errors in the nominal parameter values, and the picture measurement errors. The presence of these a priori errors and feature measure- ment noise are accounted for in a weighted-least-squares esti- mate of corrections to the nominal camera pointing angles, the spacecraft encounter orbits, and the Mars spin axis. A total of seven parameters are considered in the model: three camera orientation angles, two components of the space-
Extracting molecular Hamiltonian structure from time-dependent fluorescence intensity data

We propose a formalism for extracting molecular Hamiltonian structure from inversion of time-dependent fluorescence intensity data. The proposed method requires a minimum of a priori knowledge about the system and allows for extracting a complete set of information about the Hamiltonian for a pair of molecular electronic surfaces.
Microstructure of the Local Interstellar Cloud and the Identification of the Hyades Cloud

We analyze high-resolution UV spectra of the Mg II h and k lines for 18 members of the Hyades to study inhomogeneity along these proximate lines of sight. The observations were taken by the Space Telescope Imaging Spectrograph (STIS) instrument on board the Hubble Space Telescope (HST). Three distinct velocity components are observed. All 18 lines of sight show absorption by the Local Interstellar Cloud (LIC); 10 stars show absorption by an additional cloud, which we name the Hyades Cloud; and one star exhibits a third absorption component. The LIC absorption is observed at a lower radial velocity than predicted by the LIC velocity vector derived by Lallement & Bertin in 1992 and Lallement et al. in 1995 [vpredicted(LIC) - vobserved(LIC) = 2.9 ± 0.7 km s-1], which may indicate a compression or deceleration at the leading edge of the LIC. We propose an extension of the Hyades Cloud boundary based on previous HST observations of other stars in the general vicinity of the Hyades, as well as ground-based Ca II observations. We present our fits of the interstellar parameters for each absorption component. The availability of 18 similar lines of sight provides an excellent opportunity to study the inhomogeneity of the warm, partially ionized local interstellar medium (LISM). We find that these structures are roughly homogeneous. The measured Mg II column densities do not vary by more than a factor of 2 for angular separations of 8°, which at the outer edge of the LIC correspond to physical separations of 0.6 pc.
Sloshing of the Magnetized Cool Gas in the Cores of Galaxy Clusters

X-ray observations of many clusters of galaxies reveal the presence of edges in surface brightness and temperature, known as "cold fronts". In relaxed clusters with cool cores, these edges have been interpreted as evidence for the "sloshing" of the core gas in the cluster's gravitational potential. The smoothness of these edges has been interpreted as evidence for the stabilizing effect of magnetic fields "draped" around the front surfaces. To check this hypothesis, we perform high-resolution magnetohydrodynamics simulations of magnetized gas sloshing in galaxy clusters initiated by encounters with subclusters. We go beyond previous works on the simulation of cold fronts in a magnetized intracluster medium by simulating their formation in realistic, idealized mergers with high resolution ((Delta)x approx. 2 kpc). Our simulations sample a parameter space of plausible initial magnetic field strengths and field configurations. In the simulations, we observe strong velocity shears associated with the cold fronts amplifying the magnetic field along the cold front surfaces, increasing the magnetic field strength in these layers by up to an order of magnitude, and boosting the magnetic pressure up to near-equipartition with thermal pressure in some cases. In these layers, the magnetic field becomes strong enough to stabilize the cold fronts against Kelvin-Helmholtz instabilities, resulting in sharp, smooth fronts as those seen in observations of real clusters. These magnetic fields also result in strong suppression of mixing of high and low-entropy gas in the cluster, seen in our simulations of mergers in the absence of a magnetic field. As a result, the heating of the core due to sloshing is very modest and is unable to stave off a cooling catastrophe.
Higgs sector in anomaly mediated supersymmetry breaking scenario

In the minimal anomaly mediated supersymmetry breaking (AMSB) model, a universal contribution m0 to all the scalar masses is introduced in order to avoid the negative slepton mass problem. The Higgs spectrum and couplings are determined by four parameters: maux,m0,tanβ and sign(μ). The sign of μ affects mA at large tanβ and mh at small tanβ. The CP-odd Higgs mass mA is usually much larger than mZ and the lightest CP-even Higgs is simply analogous to the one in the standard model. The reach of the current and future Higgs searches in LEP, Tevatron and LHC for the AMSB parameter spaces in studied in detail.
Iterative Approximations of Exponential Bases on Fractal Measures

For some fractal measures it is a very difficult problem in general to prove the existence of spectrum (respectively, frame, Riesz and Bessel spectrum). In fact there are examples of extremely sparse sets that are not even Bessel spectra. In this article, we investigate this problem for general fractal measures induced by iterated function systems (IFS). We prove some existence results of spectra associated with Hadamard pairs. We also obtain some characterizations of Bessel spectrum in terms of finite matrices for affine IFS measures, and one sufficient condition of frame spectrum in the case that the affine IFS has no overlap.
AN ULTRALUMINOUS SUPERSOFT X-RAY SOURCE IN M81 : AN INTERMEDIATE-MASS BLACK HOLE?

Ultraluminous supersoft X-ray sources (ULSSSs) exhibit supersoft spectra with blackbody temperatures of 50-100 eV and bolometric luminosities above 1039 ergs s−1 and are possibly intermediate-mass black holes (IMBHs) of ≥103 M☉ or massive white dwarfs that are progenitors of Type Ia supernovae. In this Letter we report our optical studies of such a source in M81, M81-ULS1, with HST archive observations. M81-ULS1 is identified with a pointlike object, the spectral energy distribution of which reveals a blue component in addition to the companion of an asymptotic giant branch star. The blue component is consistent with the power law as expected from the geometrically thin accretion disk around an IMBH accretor but inconsistent with the power law as expected from the X-ray-irradiated flared accretion disk around a white dwarf accretor. This result is strong evidence that M81-ULS1 is an IMBH instead of a white dwarf.
The Costabel-Stephan system of boundary integral equations in the time domain

In this paper we formulate a transmission problem for the transient acoustic wave equation as a system of retarded boundary integral equations. We then analyse a fully discrete method using a general Galerkin semidiscretization-in-space and Convolution Quadrature in time. All proofs are developed using recent techniques based on the theory of evolution equations. Some numerical experiments are provided.
Noncommutative supergeometry, duality and deformations

Following Lett. Math. Phys. 50 (1999) 309, we introduce a notion of Q-algebra that can be considered as a generalization of the notion of Q-manifold (a supermanifold equipped with an odd vector field obeying {Q,Q}=0). We develop the theory of connections on modules over Q-algebras and prove a general duality theorem for gauge theories on such modules. This theorem containing as a simplest case SO(d,d,Z)-duality of gauge theories on noncommutative tori can be applied also in more complicated situations. We show that Q-algebras appear naturally in Fedosov construction of formal deformation of commutative algebras of functions and that similar Q-algebras can be constructed also in the case when the deformation parameter is not formal.
THE MAGNETOHYDRODYNAMICS OF SHOCK-CLOUD INTERACTION IN THREE DIMENSIONS

The magnetohydrodynamic evolution of a dense spherical cloud as it interacts with a strong planar shock is studied, as a model for shock interactions with density inhomogeneities in the interstellar medium. The cloud is assumed to be small enough that radiative cooling, thermal conduction, and self-gravity can be ignored. A variety of initial orientations (including parallel, perpendicular, and oblique to the incident shock normal) and strengths for the magnetic field are investigated. During the early stages of the interaction (less than twice the time taken for the transmitted shock to cross the interior of the cloud), the structure and dynamics of the shocked cloud are fairly insensitive to the magnetic field strength and orientation. However, at late times strong fields substantially alter the dynamics of the cloud, suppressing fragmentation and mixing by stabilizing the interface at the cloud surface. Even weak magnetic fields can drastically alter the evolution of the cloud compared to the hydrodynamic case. Weak fields of different geometries result in different distributions and amplifications of the magnetic energy density, which may affect the thermal and nonthermal X-ray emission expected from shocked clouds associated with, for example, supernova remnants.
On the Importance of Getting Things Done

Trend plus inaction equals drift. When a trend has external causes and no one can act to intervene, that inaction leads to drift—the unimpeded trajectory of change. Drift in the United States produces the domination of American democracy by business interests. Drift in international decisions produces global warming. Specific institutional designs for government, such as the US separation of powers, can cause the inaction that facilitates drift. More fundamentally, ingrained patterns of thinking can cause inaction. Here I argue that the long and multifaceted resistance tradition in the West contributes to inaction by focusing on stopping, rather than using, coercion.
Cross-layer analysis of the end-to-end delay distribution in wireless sensor networks

Emerging applications of wireless sensor networks (WSNs) require real-time quality-of-service (QoS) guarantees to be provided by the network. Due to the nondeterministic impacts of the wireless channel and queuing mechanisms, probabilistic analysis of QoS is essential. One important metric of QoS in WSNs is the probability distribution of the end-to-end delay. Compared to other widely used delay performance metrics such as the mean delay, delay variance, and worst-case delay, the delay distribution can be used to obtain the probability to meet a specific deadline for QoS-based communication in WSNs. To investigate the end-to-end delay distribution, in this paper, a comprehensive cross-layer analysis framework, which employs a stochastic queueing model in realistic channel environments, is developed. This framework is generic and can be parameterized for a wide variety of MAC protocols and routing protocols. Case studies with the CSMA/CA MAC protocol and an anycast protocol are conducted to illustrate how the developed framework can analytically predict the distribution of the end-to-end delay. Extensive test-bed experiments and simulations are performed to validate the accuracy of the framework for both deterministic and random deployments. Moreover, the effects of various network parameters on the distribution of end-to-end delay are investigated through the developed framework. To the best of our knowledge, this is the first work that provides a generic, probabilistic cross-layer analysis of end-to-end delay in WSNs.
Cultural Cues to Conducting Business in Venezuela

ABSTRACT This paper analyzes various characteristics of the Venezuelan culture and describes some obstacles that foreign companies face when doing business in Venezuela.
Overview of the alternative power system economic analysis model

The Alternative Power System Economic Analysis Model (APSEAM) is an interactive computer model which can be applied in three ways: (1) the model projects the annual, after-tax costs of capital investment in various conventional and non-conventional energy technologies for each and every year in the investment time horizon; (2) the model serves as an investment analysis tool; and (3) the model serves as a tool which can be used for evaluating the impact of specific policies on specific investors.
Hamiltonian electric/magnetic duality and Lorentz invariance

In noncovariant, Hamiltonian, formulation of gauge vector actions, the conditions for invariance under electric/magnetic duality transformations and their generator are transparent. Instead, satisfying Lorentz invariance — fulfilling the Dirac–Schwinger stress tensor commutators — becomes a complicated differential constraint on the Hamiltonian. The combined requirements are equivalent to the usual Lagrangian form of the duality invariance condition.
Bias-free Measurement of Giant Molecular Cloud Properties

We review methods for measuring the sizes, line widths, and luminosities of giant molecular clouds (GMCs) in molecular-line data cubes with low resolution and sensitivity. We find that moment methods are robust and sensitive, making full use of both position and intensity information, and we recommend a standard method to measure the position angle, major and minor axis sizes, line width, and luminosity using moment methods. Without corrections for the effects of beam convolution and sensitivity to GMC properties, the resulting properties may be severely biased. This is particularly true for extragalactic observations, where resolution and sensitivity effects often bias measured values by 40% or more. We correct for finite spatial and spectral resolutions with a simple deconvolution, and we correct for sensitivity biases by extrapolating properties of a GMC to those we would expect to measure with perfect sensitivity (i.e., the 0 K isosurface). The resulting method recovers the properties of a GMC to within 10% over a large range of resolutions and sensitivities, provided the clouds are marginally resolved with a peak signal-to-noise ratio greater than 10. We note that interferometers systematically underestimate cloud properties, particularly the flux from a cloud. The degree of bias depends on the sensitivity of the observations and the (u, v) coverage of the observations. In an Appendix to the paper we present a conservative, new decomposition algorithm for identifying GMCs in molecular-line observations. This algorithm treats the data in physical rather than observational units (i.e., parsecs rather than beams or arcseconds), does not produce spurious clouds in the presence of noise, and is sensitive to a range of morphologies. As a result, the output of this decomposition should be directly comparable among disparate data sets.
On quantitative histo- and cytochemistry and general reflections.

La comprehension des mecanismes fondamentaux responsable de la vie ne peut se faire qu'avec des etudes fines concernant la chimie et la fonction des unites structurales qui composent la matiere vivante. Ceci constitue le but des techniques quantitatives histo- et cytochimiques. Ce travail expose et discute ces differentes techniques biologiques
Ordinary Cosmopolitanisms: Strategies for Bridging Racial Boundaries among Working Class Men

In contrast to most literature on cosmopolitanism, which focuses on its elite forms, this article analyzes how ordinary people bridge racial boundaries in everyday life. It is based on interviews w...
Exploratory analysis of the medical record

Current patient information systems such as SCAMP have the capacity to store not only highly-structured information such as problem codes, drug lists and laboratory values, but also richer, clinically-descriptive information such as comprehensive natural language problem summaries and other textual data that retain the full clinical information used by physicians in managing their patients. The clinical importance, richness, and extensiveness of this information suggest that techniques which allow computers to process textual data may play a helpful role in clinical research. The analysis programs of the SCAMP system have been developed to explore the potential of this approach.
Minimum Ellipsoid Bounds for Solutions of Polynomial Systems via Sum of Squares

We study ellipsoid bounds for the solutions $$(x,\mu) \in \mathbb{R}^{n} \times \mathbb{R}^{r}$$ of polynomial systems of equalities and inequalities. The variable ? can be considered as parameters perturbing the solution x. For example, bounding the zeros of a system of polynomials whose coefficients depend on parameters is a special case of this problem. Our goal is to find minimum ellipsoid bounds just for x. Using theorems from real algebraic geometry, the ellipsoid bound can be found by solving a particular polynomial optimization problem with sums of squares (SOS) techniques. Some numerical examples are also given.
PREDICTION OF UNDERGROUND NUCLEAR EXPLOSION EFFECTS IN WAGON WHEEL SANDSTONE.

Project Wagon Wheel is a joint study by Lawrence Livermore Laboratory (LLL) and El Paso Natural Gas Company (EPNG) to investigate the technical concept of nuclear stimulation of a natural gas reser...
The role of initial conditions and forcing uncertainties in seasonal hydrologic forecasting

[1] A series of hydrologic forecasts with lead times up to 6 months are conducted to investigate the relative contributions of atmospheric forcing and hydrologic initial conditions (IC) to the overall errors in hydrologic forecasting during cold and warm seasons. These experiments are known as the ensemble streamflow prediction (ESP) and the reverse-ESP (R-ESP). Analysis of these hindcasts suggests that IC uncertainties outweigh forcing uncertainties thus dominating forecast errors in a short lead time up to about 1 month; at longer lead times, forcing uncertainties become a more important contributor. Further investigation shows that forecast errors at short lead times due to uncertain ICs are mainly determined by the prescribed IC variability, while the evolution of forecast errors due to imperfect atmospheric forcings mainly corresponds to the interannual variability of precipitation. With respect to difference in forecasts initialized in winter and summer times, ICs tend to have longer impacts on warm season forecasts than on cold season ones, due mainly to drier initial moisture state in the summer time. As far as the basin size is concerned, we find that the larger the basin, the stronger the impacts from ICs at short lead times. Small basins are more sensitive to forcing fields. Regardless of basin size, forcing uncertainties dominate relative forecast errors for long lead times. In order to see whether statistically downscaled forcing fields from dynamic climate models are more skillful than traditional ESP, we conducted additional ESP-type experiments using the statistically downscaled climate forecast system (CFS) fields to drive the hydrological model. In comparison to traditional ESP, the IC errors show a larger impact on the forecasts when forced by the CFS fields, which suggests that the latter contains more skill than the traditional ESP approach.
Microwave-promoted Pd-catalyzed cyanation of aryl triflates: a fast and versatile access to 3-cyano-3-desoxy-10-ketomorphinans.

A methodology for the microwave-promoted conversion of triflates to the corresponding nitriles by using 8% equiv of Pd(Ph3P)4 as the catalyst and 2.0 equiv of Zn(CN)2 as the cyanide source has been developed. This method is highly efficient for the preparation of 3-cyano-3-desoxy-10-ketomorphinans. The reaction was generally completed in 15 min at 200 °C and produced products in greater than 86% yields.
Baryons and branes in anti de Sitter space

In the mapping from four-dimensional gauge theories to string theory in AdS space, many features of gauge theory can be described by branes wrapped in different ways on S5, RP5, or subspaces therefore. These include a baryon vertex coupling N external charges in the fundamental representation of SU(N), a bound state of k gluons in SO(2k) gauge theory, strings coupled to external charges in the spinor representation of the gauge group, and domain walls across which the low energy gauge group changes.
BRST Extension of Geometric Quantization

Consider a physical system for which a mathematically rigorous geometric quantization procedure exists. Now subject the system to a finite set of irreducible first class (bosonic) constraints. It is shown that there is a mathematically rigorous BRST quantization of the constrained system whose cohomology at ghost number zero recovers the constrained quantum states. Moreover this space of constrained states has a well-defined Hilbert space structure inherited from that of the original system. Treatments of these ideas in the physics literature are more general but suffer from having states with infinite or zero "norms" and thus are not admissible as states. Also BRST operators for many systems require regularization to be well-defined. In our more restricted context, we show that our treatment does not suffer from any of these difficulties.
Fluctuation Theorems for Entropy Production and Heat Dissipation in Periodically Driven Markov Chains

Asymptotic fluctuation theorems are statements of a Gallavotti-Cohen symmetry in the rate function of either the time-averaged entropy production or heat dissipation of a process. Such theorems have been proved for various general classes of continuous-time deterministic and stochastic processes, but always under the assumption that the forces driving the system are time independent, and often relying on the existence of a limiting ergodic distribution. In this paper we extend the asymptotic fluctuation theorem for the first time to inhomogeneous continuous-time processes without a stationary distribution, considering specifically a finite state Markov chain driven by periodic transition rates. We find that for both entropy production and heat dissipation, the usual Gallavotti-Cohen symmetry of the rate function is generalized to an analogous relation between the rate functions of the original process and its corresponding backward process, in which the trajectory and the driving protocol have been time-reversed. The effect is that spontaneous positive fluctuations in the long time average of each quantity in the forward process are exponentially more likely than spontaneous negative fluctuations in the backward process, and vice-versa, revealing that the distributions of fluctuations in universes in which time moves forward and backward are related. As an additional result, the asymptotic time-averaged entropy production is obtained as the integral of a periodic entropy production rate that generalizes the constant rate pertaining to homogeneous dynamics.
Innovation‐oriented operations strategy typology and stage‐based model

Purpose – This paper aims to examine how firms, operating in mature and growing industries, can improve the alignment of their operations strategy to fit situations characterized by varying rates of industry growth and technological changes.Design/methodology/approach – The authors enhance the operations strategy typology presented by Lei and Slocum by incorporating an enhanced set of competitive priorities and supporting structure/infrastructure requirements into their four cell matrix. They then introduce a stage‐based model of environmental dynamism and complexity that can foster major transitions in operations strategy.Findings – Industry growth and technological change interact to create alternative environments with varying levels of dynamism and complexity requiring realignment of operations strategy. With increasing rates of technological change, the authors emphasize an urgent need to include innovation as a competitive priority (along with cost, quality, delivery and flexibility) to proactively ...
Convergent approaches to the Vitamin D skeleton using a transition metal catalyzed carbometalation/capture strategy

Abstract Two concise, highly convergent strategies for the synthesis of Vitamin D derivatives are presented. Beginning with synthons of exceedingly low complexity, each approach utilizes a transition metal catalyzed intramolecular carbometalation for the stereoselective formation of the critical (bis)exocyclic diene subunit.
Are the Fed's Inflation Forecasts Still Superior to the Private Sector's?

Abstract We examine the relative improvement in forecasting accuracy of the Federal Reserve (Greenbook forecasts) and private-sector forecasts (the Survey of Professional Forecasters and Blue Chip Economic Indicators)for inflation. Previous research by Romer and Romer [Romer, Christina, David, Romer, 2000. Federal reserve information and the behavior of interest rates. American Economic Review 90, 429–457], and Sims [Sims, Christopher, 2002. The role of models and probabilities in the monetary policy process. Brookings Papers on Economic Activity 2, 1–62] shows that the Fed is more accurate than the private sector at forecasting inflation. In a separate line of research, Atkeson and Ohanian [Andrew, Atkeson, Ohanian, Lee E., 2001. Are Phillips curves useful for forecasting inflation? Federal Reserve Bank of Minneapolis Quarterly Review 25, 2–11] and Stock and Watson [Stock, James, Watson, Mark, 2007. Why has U.S. inflation become harder to forecast? Journal of Money, Credit and Banking 39] document changes in the forecastability of inflation since the Great Moderation. These works suggest that the reduced inflation variability associated with the Great Moderation was mostly due to a decline in the variability of the predictable component inflation. We hypothesize that the decline in the variability of the predictable component of inflation has evened the playing field between the Fed and the private sector and therefore led to a narrowing, if not disappearance, of the Fed’s relative forecasting advantage. We find that the Fed’s forecast errors remain significantly smaller than the private sector’s but the gap has narrowed considerable since the mid-1980s, especially after 1994.
On the conjugacy of the aurora: High and low latitudes

On December 5, 1983 the polar orbiting satellites NOAA-7 and DMSP-F6, while in opposite hemispheres, each crossed a narrow structure of auroral electron precipitation at nearly the same Universal Time (UT) and at the same high magnetic latitude local time location. The Operational Line Scanner (OLS) image taken by DMSP-F6 of the northern polar region showed that this enhancement was associated with a sun-aligned arc (SAA) which extended poleward from the midnight sector auroral zone and passed across the polar cap very near to the magnetic pole. The DMSP-F6 plasma measurements showed particle precipitation at background levels in the regions adjacent to the SAA suggesting that those magnetic field lines connected to the interplanetary medium via the northern tail lobe. NOAA-7 observations show that the analogous precipitation structure in the southern hemisphere was embedded in a region of low intensity ion and electron precipitation which had the characteristics of the plasma sheet population. Comparisons between the boundaries of the lower latitude auroral zone precipitation and the electron distributions at those boundaries were also made. The results of these comparisons together with those made for the high latitude SAA argue for a high degree of inter-hemisphere conjugacy in the electron precipitation over a wide range of invariant magnetic latitudes.
Block-structured solution of Euler equations for transonic flows

A block-structured solution scheme is developed for the solution of Euler equations for steady three-dimensional transonic flows*. The Euler equations are expressed in terms of Clebsch variables w = v + Svn. The resulting set of equations for conservation of mass, entropy (5) and the Clebsch variable j\ are solved using a block-based relaxation scheme. The flowfield is divided into a series of individual blocks representing local regions of the flowfield. The employed grid generation scheme provides local refinement of each block yet ensures one-to-one matching of grid points on the surfaces of adjoining blocks. For each of the blocks, either potential or Euler equations can be solved. For every block, the conservation of mass equation is solved to determine . For blocks with rotationality, two additional equations for determining S and T\ are solved. In this paper, the basic steps of the developed solution scheme are presented. The computational considerations involved in utilizing the present scheme are demonstrated for several two-dimensional sample problems.
The light cone in string theory

The causal boundary of string propagation-defined as the hypersurface in loop space bordering the timelike (spacelike) domains in which two successive measurements of the string field do (do not) interfere with one another-is argued to be O= integral d sigma ( delta X( sigma ))2= Sigma infinity l=- infinity delta x-lmu delta xmu l. Some possible consequences are discussed.
D meson hadronic decays at CLEO-c

The recent CLEO-c results on hadronic decays of D and D{sub s} mesons are presented. First the absolute branching fractions for D and D{sub s} mesons using a double tag technique are discussed, then are the Cabibbo suppressed decays and doubly Cabibbo suppressed decays. Finally, I present the inclusive and rare decay modes and other measurements from CLEO-c. These decays illuminate a wide range of physics. A brief theoretical introduction is given before the corresponding discussion on measurement.
The role of fragility in EHL entrapment

Abstract Experimental measurements of time dependent film thickness in entrapped liquids, measurements of viscosity under pressure, and simulations using realistic pressure–viscosity models contribute to improved understanding of the mechanisms of entrapment formation and persistence. The ambient viscosity and pressure–viscosity coefficient affect entrapment only as much as they are predictors of behavior at much higher pressure. Fragile liquids, such as lubricating oils, experience rapid increase in sensitivity of dynamic properties to temperature and pressure as the glass transition is approached. The fragility property of lubricants appears to be of overwhelming importance to entrapment which experimental evidence indicates will reduce starting friction.
Regioselective Asao–Yamamoto Benzannulations of Diaryl Acetylenes

Asao–Yamamoto benzannulations transform diarylalkynes into 2,3-diarylnaphthalenes, and regioselective variants of this reaction are of interest for synthesizing substituted polycyclic aromatic systems. It is shown that regioselective cycloadditions occur when one alkyne carbon preferentially stabilizes developing positive charge. Simple calculations of the relative energies of carbocations localized at each alkyne carbon of a substrate predict the regioselectivity, which is not eroded by bulky substituents, including 2,6-disubstituted aryl groups.
Chiral N-phosphonyl imine chemistry: Asymmetric synthesis of α,β-diamino esters by reacting phosphonyl imines with glycine enolates

Chiral phosphonyl imines attached with N-isopropyl protection group were found to react with lithium glycine enolates under convenient conditions to give alpha,beta-diamino esters. Thirteen examples have been examined in good to excellent chemical yields (85-97%) diastereoselectivity (up to 99% de). By treating with HBr at room temperature, the chiral auxiliary can be readily removed and recycled. The absolute structure has been unambiguously determined by converting a product to a known sample.
Heterogeneous deformation in a ductile fold-thrust belt: The Proterozoic structural history of the Tusas Mountains, New Mexico

The presence of widely variable deformational styles in the Proterozoic terranes of northern New Mexico has led to conflicting interpretations of the geologic history of the region. Proterozoic rocks of the Tusas Mountains display a range of deformational styles typical of northern New Mexico and suggest a model for interpreting the heterogeneity. Three broad types of structural domains have been identified: (1) regions characterized by complex polyphase fold patterns, (2) regions dominated by a single intense schistosity, and (3) regions with nearly pristine primary sedimentary and volcanic structures. Domain boundaries range from continuous deformational gradients to localized faults or shear zones. Structural and metamorphic evidence suggests that all domains were deformed in a single regional shortening event. The deformation occurred during prograde metamorphism at upper greenschist- and lower amphibolite-facies conditions. Despite the metamorphic grade, kilometer-thick massive units were shortened by folding and thrusting, producing geometries similar to those of thin-skinned deformational belts. Regions located beneath the ramps of large-scale ductile thrusts preserve primary structures and simple apparent deformational histories because much of the regional strain was partitioned to the overlying faults. Regions structurally above ramps display complex multiple fold patterns with strain histories that progress from subhorizontal shearing to upright folding and shortening. Regions away from ramps have an intense multi-phase schistosity and a deformational history involving progressive simple shearing. The large scale of the domains (as much as 75 km 2 ) and the extreme structural heterogeneity from domain to domain may reflect, at least in part, the competence, homogeneity, and extreme thickness (>1 km) of the Ortega orthoquartzite. Spectacularly refolded and multiply sheared regions in the Tusas Mountains reflect complex local strain environments that cannot be correlated from domain to domain. The kinematic histories of these environments are locally important but are misleading on a regional scale. The regional kinematic history was relatively simple, involving a single shortening event. Deformational styles in other Proterozoic terranes in northern New Mexico are directly comparable to those of the Tusas Mountains and can be interpreted in terms of this large-scale heterogeneous shortening model.
Grading, Minimum Quality Standards, and the Labeling of Genetically Modified Products

We relate the labeling of genetically modified (GM) products to the theory of grading and minimum quality standards. The model represents three stages in the supply chain, assumes a vertical product differentiation framework, allows for the accidental commingling of non-GM products, and treats regulation as a purity threshold for non-GM products. We find that a non-GM purity level that is too strict leads to the disappearance of the non-GM product, and that some quality standard benefits farmers. Indeed, the standard that is optimal from the perspective of producers is stricter than what is optimal for consumers and for societal welfare.
Definition of a User Environment in a Ubiquitous System

Currently, users interact with computer systems at the level of applications or devices. In the reality of ubiquitous computing it is neither acceptable nor scalable to expect that users keep track of all their activities, explicitly migrate them, and configure resources as they need them. We conceptualize a user environment as an aggregation of the whole activity of a user in a ubiquitous system. In this paper we define a user environment in a ubiquitous system. We also propose a software architecture that maintains user environments, deploys and adjusts them to underlying computing spaces, as necessary.
Moving bottlenecks: A numerical method that converges in flows

This paper presents a numerical method to model kinematic wave (KW) traffic streams containing slow vehicles. The slow vehicles are modeled discretely as moving boundaries that can affect the traffic stream. The proposed scheme converges in flows, densities and speeds without oscillations, and therefore can be readily used in situations where one wishes to model the effect of the traffic stream on the bottlenecks too.
Standard enthalpies of formation of some lanthanide indium compounds by high temperature direct synthesis calorimetry

Abstract The standard enthalpies of formation of some lanthanide indium compounds have been measured by high temperature direct synthesis calorimetry at 1373±2 K. The following results (in kJ/mole of atoms) are reported: CeIn3(−49.1±2.0); PrIn3(−51.3±2.4); NdIn3(−51.5±1.8); SmIn3(−52.0±3.1); GdIn3(−48.5±2.2); TbIn3(−53.5±2.5); DyIn3(−48.1±2.0); Ho5In3(−50.2±2.0); Er5In3(−47.7±2.5); TmIn3(−47.5±3.4); Lu5In3(−52.3±1.9). The results are compared with some earlier values by calorimetry and by EMF measurements. They are also compared with the predicted values of Miedema and coworkers. We also compare our measured enthalpies of formation with the predictions by Gschneidner for lanthanide alloys.
A graduate course on finite element analysis for electromagnetic applications

The author describes a graduate course on finite element analysis for electromagnetic applications that is offered at Marquette University. This course covers the theoretical background that is essential to learning how to model electromagnetic devices. The course stresses the practical aspects of applying the finite element method to engineering and design problems. >
Interpolation of observer state feedback controllers for gain scheduling

The authors propose a method of interpolating linear time-invariant controllers with observer state feedback structure in order to generate a continuously varying family of controllers that stabilizes a family of linear plants. Gain scheduling is a motivation for this work, and the interpolation method yields guidelines for the design of gain scheduled controllers. The method is illustrated with the design of a missile autopilot using loop-shaping H-infinity controllers.
Midterm Results of a Femoral Stem With a Modular Neck Design: Clinical Outcomes and Metal Ion Analysis

Abstract Modular neck femoral stems have a higher-than-anticipated rate of failure in registry results, but large single-center cohort studies are lacking. This is a retrospective cohort of 152 hips implanted with a single titanium stem with a modular titanium neck, presenting clinical, radiographic, and metal ion results at a mean 4.5-year follow-up. Five hips were revised during the study period, for an overall Kaplan–Meier survival of 0.894 at 8 years. There was one modular neck fracture (0.66%), but others demonstrated corrosion or adverse tissue reaction. Serum metal levels demonstrated wide variability. Despite good clinical results in the majority of patients, we confirmed an increased rate of femoral revision at mid-term follow-up, and therefore urge caution in the use of this particular stem design.
THE EFFECTS OF ASPECTUAL CLASS ON THE TEMPORAL STRUCTURE OF DISCOURSE: SEMANTICS OR PRAGMATICS?

But in cases where such indicators are absent, it has been observed by Jespersen, and in more detail in a series of recent articles by Helen Dry (1978, ms.), that the aspectual classes of the predicates in the discourse, i.e. their Aktionsarten, seem to determine these temporal relationships. (By aspectual class I refer to the taxonomy of predicates originating with Aristotle and known in the Anglo-Saxon tradition through the work of Ryle, Kenny and Vendler; I will refer to these classes by Vendler's names States, Activities, Accomplishments and Achievements, and I assume that the reader is acquainted with the syntactic and semantic tests usually employed to distinguish these categories (cf. Vendler, 1967; Dowty, 1979).) If a sentence in a narrative contains an accomplishment or achieve ment predicate but no definite time adverb, that sentence is understood to describe an event occurring later than the time of the previous sentence's event (or in the literary analyst's terms, narrative time "moves forward" in the second sentence). For example, (2) indicates this phenomenon with an accomplishment, walk over to him,
Buyer search and price dispersion:a laboratory study

We study markets with costly buyer search in which sellers simultaneously post prices. Buyers costlessly observe one or (with probability 1� q) two of the posted prices, and can accept one or pay to search again. The experiment varies q, the search cost, and the number of buyers. Equilibrium theory predicts a unified very low (high) price for q=0 (q=1) and predicts specific distributions of dispersed prices for q=1/3 and 2/3. Actual prices conform closely to the predictions in some treatments. Buyers’ reservation prices are biased away from the extremes, however, and sellers’ prices have positive autocorrelation and cross-sectional correlation.
Expectations, Life Expectancy, and Economic Behavior

This study analyzes responses to a questionnaire designed to elicit subjective expectations and probabilities of survival. People do extrapolate past improvements in longevity when they determine their subjective horizons and they are fully aware of levels of and movements within todays life tables. The subjective distribution has greater variance than its actuarial counterpart; and the subjective variance decreases with age. The implications of these findings for optimal Social Security for the construction of annuities for the analysis of savings behavior and for evaluating lifetime earnings are discussed. The data were collected in the United States from a sample of 411 white male economists and a sample of 363 white males in a midwestern SMSA. (EXCERPT)
Hardware support for large atomic units in dynamically scheduled machines

Microarchitectures that implement conventional instruction set architectures are usually limited in that they are only able to execute a small number of microoperations concurrently. This limitation is due in part to the fact that the units of work that the hardware treats as indivisible are small. While this limitation is not important for microarchitectures with a low level of functionality, it can be significant if the goal is to build hardware that can support a large number of microoperations executing concurrently. In this paper we address the tradeoffs associated with the sizes of the various units of work that a processor considers indivisible, or atomic. We argue that by allowing larger units of work to be atomic, restrictions on concurrent operation are reduced and performance is increased. We outline the implementation of a front end for a dynamically scheduled processor with hardware support for large atomic units. We discuss tradeoffs in the design and show that with a modest investment in hardware, the run-time advantages of large atomic units can be realized without the need to alter the instruction set architecture.
Boosting in the presence of noise

Boosting algorithms are procedures that ''boost'' low-accuracy weak learning algorithms to achieve arbitrarily high accuracy. Over the past decade boosting has been widely used in practice and has become a major research topic in computational learning theory. In this paper we study boosting in the presence of random classification noise, giving both positive and negative results. We show that a modified version of a boosting algorithm due to Mansour and McAllester (J. Comput. System Sci. 64(1) (2002) 103) can achieve accuracy arbitrarily close to the noise rate. We also give a matching lower bound by showing that no efficient black-box boosting algorithm can boost accuracy beyond the noise rate (assuming that one-way functions exist). Finally, we consider a variant of the standard scenario for boosting in which the ''weak learner'' satisfies a slightly stronger condition than the usual weak learning guarantee. We give an efficient algorithm in this framework which can boost to arbitrarily high accuracy in the presence of classification noise.
Chemistry and Reactions of Reactive Oxygen Species in Foods

Reactive oxygen species (ROS) is formed enzymatically, chemically, photochemically, and by irradiation of food. It is also formed by the decomposition and the inter-reactions of ROS. The hydroxy radical is the most reactive ROS and then followed by singlet oxygen. Reactions of ROS with food components produce undesirable volatile compounds and carcinogens, destroy essential nutrients, and change the functionalities of proteins, lipids, and carbohydrates. Lipid oxidation by ROS produces low-molecular-weight volatile aldehydes, alcohols, and hydrocarbons. ROS causes crosslink or cleavage of proteins. ROS produces low-molecular-weight carbonyl compounds from carbohydrates. Vitamins are easily oxidized by ROS, especially singlet oxygen. The singlet oxygen reaction rate was the highest in β-carotene followed by tocopherol, riboflavin, vitamin D, and ascorbic acid.
Pricing to Market in Business Cycle Models

This paper evaluates the performance of leading micro-founded pricing-to-market frictions vis-a-vis a set of robust stylized facts about international prices. In order to make that evaluation meaningful, we embed each friction into a unified IRBC framework and parameterize the models in a uniform way. Our goal is to evaluate the broad-based applicability of these frictions for policy-oriented DSGE modeling by documenting their strengths and weaknesses. We make three points: (i) the mechanisms generating pricing to market are not always neutral to business cycle dynamics of quantities, (ii) some mechanisms require producer markups at least 50% to account for the full range of estimates of the empirical exchange rate pass-through to export prices of 35%-50%, (iii) some frictions crucially depend on a particular driver of uncertainty in the underlying model.